Skip to main content

SETD2 variation correlates with tumor mutational burden and MSI along with improved response to immunotherapy

Abstract

Background

SETD2 protects against genomic instability via maintenance of homologous recombination repair (HRR) and mismatch repair (MMR) in neoplastic cells. However, it remains unclear whether SETD2 dysfunction is a complementary or independent factor to microsatellite instability-high (MSI-H) and tumor mutational burden-high (TMB-H) for immunocheckpoint inhibitor (ICI) treatment, and little is known regarding whether this type of dysfunction acts differently in various types of cancer.

Methods

This cohort study used multidimensional genomic data of 6726 sequencing samples from our cooperative and non-public GenePlus institute from April 1 through April 10, 2020. MSIsensor score, HRD score, RNAseq, mutational data, and corresponding clinical data were obtained from the TCGA and MSKCC cohort for seven solid tumor types.

Results

A total of 1021 genes underwent target panel sequencing reveal that SETD2 mutations were associated with a higher TMB. SETD2 deleterious mutation dysfunction affected ICI treatment prognosis independently of TMB-H (p < 0.01) and had a lower death hazard than TMB-H in pancancer patients (0.511 vs 0.757). Significantly higher MSI and lower homologous recombination deficiency were observed in the SETD2 deleterious mutation group. Improved survival rate was found in the MSKCC-IO cohort (P < 0.0001) and was further confirmed in our Chinese cohort.

Conclusion

We found that SETD2 dysfunction affects ICI treatment prognosis independently of TMB-H and has a lower death hazard than TMB-H in pancancer patients. Therefore, SETD2 has the potential to serve as a candidate biomarker for ICI treatment. Additionally, SETD2 should be considered when dMMR is detected by immunohistochemistry.

Peer Review reports

Background

In the past decade, the use of immune checkpoint inhibitors (ICIs) has revolutionized the treatment of a variety of tumors, including lung cancer, melanoma, colorectal cancer, and renal cell carcinoma [1, 2]. However, only some tumors, such as Hodgkin's lymphoma and tumors with high microsatellite instability (dMMR or MSI-H), respond well to ICIs with an objective response rate (ORR) of 53–87%; the ORR of most tumors, such as non-small cell lung cancer, head and neck tumors, gastroesophageal tumors, bladder urothelial tumors, renal cell carcinoma, and hepatocellular carcinoma, is much lower (15–25%) [3, 4]. Meta analysis results showed that the incidence of grade 3–4 immunotoxicity was approximately 10–24% with programmed cell death protein 1( PD-1) or cytotoxic T lymphocyte-associated antigen-4 (CTLA-4) monotherapy [5, 6], and reached 59% with combined immunotherapy [7]. Therefore, identifying prognostic biomarkers is urgently needed to optimize patient benefits, minimize toxicity risk, and guide clinical approaches. Among all prognostic biomarkers, the first FDA approved biomarker was PD-L1; however, PD-L1 shows low negative predictive value, dynamic changes in expression, and lack of a confirmed threshold between different detection method [8]. Another FDA approved and promising biomarker was MSI-H detected by polymerase chain reaction or dMMR detected by immunohistochemistry, and patients with this biomarker showed an ORR rate of 53% to immunotherapy [3]. Regretfully, MSI-H mainly occurred in endometrial cancer, colorectal cancer, and gastric cancer with rates of just 31.37%, 19.72%, and 19.09%, respectively [9]. Subsequently, the FDA approved pembrolizumab for adults and children with TMB-H solid tumors; however this is applicable to only 13% of solid tumors and the ORR was limited to about 29% [10]. Given these limitations, the aforementioned biomarkers do not guarantee therapeutic benefits. An increasing number of studies have shown that patients with somatic alterations to genes involved in DNA damage repair (DDR), such as BRCA1 DNA repair associated (BRCA1), BRCA2 DNA repair associated (BRCA2); mismatch repair (MMR) genes including MSH2 (mutS homolog 2), MSH6 (mutS homolog 6), MLH1 (mutL homolog 1), and PMS2 (PMS1 homolog 2); DNA polymerase epsilon, catalytic subunit (POLE) and the DNA polymerase delta 1, catalytic subunit (POLD1) are more likely to elicit a durable anti-tumor immune response from ICI treatment, demonstrating an important role or DDR-related genes as prognostic biomarkers [4, 11,12,13,14].

The SET domain containing 2 histone lysine methyltransferase (SETD2) gene encodes the functional domain of an enzyme that trimethylates histone H3 at lysine 36 (H3K36me3), which mediates MMR in a way that removes lesions associated with a persistently open chromatin structure in early replication, and preferentially safeguards active transcripts during replication by recruiting hMutSa which can quickly identify the mismatch to initiate the MMR reaction [15, 16]. SETD2 also favors homologous recombination repair (HRR) via activation of ataxia-telangiesctasia mutated (ATM) and formation of RAD51 presynaptic filaments upon DNA double-strand breaks [17]. Loss of SETD2 function may afford an alternative mechanism for p53-mediated checkpoint inactivation and a strong reduction in DDR, resulting in alterations in DNA regulation, increased spontaneous mutations, and chromosomal instability [18]. Deleterious mutations in SETD2 have been implicated in a wide range of solid tumors, including renal cancer, lung cancer, melanoma, gastrointestinal cancer, and endometrial cancer [19, 20]. Given the preclinical evidence, whether SETD2 dysfunction was a complementary or independent factor to MSH-H and TMB to predict the prognostic of ICIs treatment needed to be figure out and whether this kind of dysfunction acted differently in different cancer types warrants further study. So this study was conducted. We inferred that patients with SETD2 deficiency may benefit from immunotherapy through higher-TMB, more unstable microsatellites or other mechanism and we test this hypothesis in Chinese population from our corroborative GenePlus institute and the American population from TCGA [21] and MSKCC [22, 23] cohort.

Methods

Patients and samples

We used a GenePlus-Beijing Clinical Sequencing cohort from March 2018 to April 2020 to evaluate 6726 Chinese pan-cancer patients (Table S1). Among them, 375 patients with SETD2 mutations were identified. Upon reviewing their treatment, response, and overall survival, 362 patients were excluded due to 1) only receiving one to three cycles of ICIs treatment, 2) incomplete imaging data, 3) incomplete follow-up data, or 4) a benign tumor. The remaining 13 patients receiving ≥ 4 cycles of ICIs treatment from nine cancer centers were selected for survival analysis. A customized panel of 1021 genes (Table S2) were sequenced in the GenePlus cohort containing whole exons. In addition, selected introns of 288 common driver genes and high frequency mutant regions recorded in the Catalogue of Somatic Mutations in Cancer (COSMIC, http://cancer.sanger.ac.uk/cosmic) were added for 733 genes.

Prediction of the functional impact of mutations

We used the functional impact predicting tools Sorting Intolerant From Tolerant (SIFT) and Polymorphism Phenotyping v2 (PolyPhen-2), which were integrated in the Ensembl Variant Effect Predictor (http://uswest.ensembl.org/info/docs/tools/vep/index.html), to predict the effects of missense mutations on protein function. A mutation with a SIFT score < 0.05 was predicted to be deleterious; PolyPhen-2 scores of > 0.9 and 0.447–0.9 were considered as probably damaging and possibly damaging, respectively. In this study, a deleterious mutation was defined as any form of the following: deleterious mutations predicted by SIFT, a possibly/probably damaging mutation predicted by PolyPhen-2, a nonsense mutation, a stop-gain mutation, a frameshift deletion, a frameshift insertion, an inframe deletion, or an inframe insertion. Any gene with a deleterious mutation was marked as mut + , and those without a genomic alteration or deleterious mutation were marked as mut-.

Tumor mutation burden analysis

TMB was defined as the total nonsynonymous mutation counts after filtering by t_alt/(t_alt + t_ref) ≥ 0.05. In the GenePlus cohort, nonsynonymous mutations included missense, cds-del, cds-ins, cds-indel, frameshift, nonsense, stop-gain, stop-retain, and init-loss. In the MSKCC-IMPACT [24] and The Cancer Genome Atlas [21] (TCGA) cohort, nonsynonymous mutations included frameshift_del, frameshift_ins, inframe_del, inframe_ins, missense mutation, nosense_mutation, nonstop mutation, and translation_start_site mutations. A frameshift in the Memorial Sloan Kettering Cancer Center (MSKCC) database was also included. In the POPLAR/PAK cohort, nonsynonymous mutations included missense and nonsense mutations. In the present study, the upper quartile of TMB was deemed as TMB-high (TMB-H).

Comparisons were done between SETD2 mut + , BRCA1/2 mut + (BRCA1 or BRCA2 deleterious mutations), MMR genes mut + (MLH1, MSH2, MSH6, or PMS2 deleterious mutations), POLE/D1 mut + (POLE or POLD1 deleterious mutations), and a None group (without SETD2, BRCA1, BRCA2, MLH1, MSH2, MSH6, PMS2, POLE, or POLD1 deleterious mutations) using the Wilcoxon rank-sum test by R (version 3.6.0).

MSIsensor and HRD score

MSIsensor [25] is a tool developed for determining the MSI status by quantifying the percentage of unstable microsatellites. We downloaded the MSIsensor scores of TCGA pan-cancer samples from Mandal R. et al. [26]. A MSIsensor score ≥ 4 was denoted as MSH-H [27, 28]. HRD is the functional defect in HRR. In our study, we downloaded the HRD score of TCGA patients from a published article [29]; the HRD score was equal to the unweighted numeric sum of the number of subchromosomal loss of heterozygosity (LOH) regions longer than 15 Mb, the number of regions of allelic imbalance that extended to one of the subtelomeres but did not cross the centromere [the number of telomeric allelic imbalances (TAIs)], and the number of break points between regions longer than 10 Mb after filtering out regions shorter than 3 Mb [large-scale state transitions (LSTs)]. The higher the HRD score, the more abnormal the homologous recombination repair.

CIBERSORT analysis using TCGA data

The CIBERSORT [30] algorithm (https://cibersort.stanford.edu/) was used to quantify the relative fraction of 22 immune cell types by mRNA expression data. In this study, 3702 TCGA samples from seven cancer types were uploaded for estimation of the abundance of cell types. After estimation, 2360 output cases with P-values < 0.05 were included for further Wilcoxon rank-sum test analysis.

ESTIMATE analysis using TCGA data

The ESTIMATE [31] algorithm was used to quantify the immune and stromal components in a tumor tissue by uploading mRNA expression data. In this study, the ESTIMATE package in R (version 3.6.0) and 3702 TCGA mRNA expression datasets from seven cancer types were used to calculate stromal, immune, and estimate scores. Immune scores were further analyzed by Wilcoxon rank-sum test to compare the differences in immune scores between SETD2 mut + groups and SETD2 mut- groups.

Different gene expression profiles

There were 3892 transcripts per million (TPM) datasets from patients with seven cancer types including bladder urinary cancer, colorectal adenocarcinoma, renal carcinoma, non-small cell lung cancer (NSCLC), skin cutaneous melanoma, stomach adenocarcinoma, and endometrial carcinoma in the TCGA cohort that were downloaded from https://www.cbioportal.org/. The mRNA expression from cBioPortal was quantified by RNA seq by expectation–maximization (RSEM) [32] and was log-transformed as log2 (data + 1) for Wilcoxon rank-sum test analysis.

Gene set enrichment analysis

Gene set enrichment analysis (GSEA) is a computational method that determines whether the expression of a predefined gene set differs significantly between two phenotypes. There are three key elements in the GSEA method including the enrichment score (ES), the nominal P value, and a normalized enrichment score (NES). The ES is the primary statistic for examining gene set enrichment results and the NES is used to normalize the ES account according to the size of the set. The nominal P value estimates the statistical significance of the ES, with a nominal P < 0.05 considered statistically significant. Single sample GSEA (ssGSEA) [33] is an extension of GSEA that works at the level of one sample each time rather than the whole population, as with the GSEA that determines whether the expression of a predefined gene set differs significantly between two phenotypes. The enriched score represented the degree to which our input gene set was up or downregulated in each corresponding sample.

Statistical analysis

Survival curves were delineated by the Kaplan–Meier method, and the Log-rank method was used to assess the significance between groups. Univariate and multivariate Cox regression analyses were implemented to calculate the hazard ratio on progression-free survival (PFS) and overall survival (OS). Multivariate binary logistic regression was used to analyze the influencing factors of TMB-H. If TMB, TPM, immune scores, or 22 immune cell fractions estimated by CIBERSORT were normally distributed, a Student’s t-test was used to determine the differences between two groups; otherwise, the Wilcoxon rank-sum test was used. Wilcoxon rank-sum test analyses were conducted by R-3.6.0 [34], and others by GraphPad Prism (version 8.0.1) or SPSS version 25.0 (SPSS, Inc.). All tests were two-sided and all reported P values did not adjust for multiple comparisons, with P < 0.05 denoted as statistically significant.

Results

The prevalence of SETD2 mutations in pan-cancer

To examine the occurrence of SETD2 mutations in different cancers, we first evaluated the SETD2 mutational prevalence (Fig. 1A). A total of 6726 samples were analyzed and the results showed that renal cell carcinoma had the highest SETD2 mutational frequency (13/93; 13.98%) followed by prostate cancer (5/52; 9.62%), urothelial carcinoma (7/75; 9.33%), glioma (17/215; 7.91%), hepatic carcinoma (15/195; 7.69%), colorectal cancer (74/1156; 6.4%), melanoma (8/136; 5.88%), and NSCLC (203/3630; 5.84%). The Fig. 1B was drawn with R’ “maftool” package, which showed the mutation sites and mutation types in a given gene. Further statistical analysis revealed non-hotspot mutations within SETD2 (Fig. 1B) with missense mutations predominating in NSCLC, melanoma, and colorectal cancer, whereas truncating mutations predominated in renal cell carcinoma (Fig. 1C). The functional impact predicting tools SIFT and PolyPhen-2 were used to predict deleterious missense mutations; samples with and without SETD2 deleterious mutations were marked as SETD2 mut + and SETD2 mut-, respectively.

Fig.1
figure 1

A Incidence of SETD2 deleterious mutations in pan-cancer. Red, green, and blue bars represent the frequency of SETD2 nonsynonymous mutations in pan-cancer in the Geneplus cohort. (Nonsynonymous mutations include frameshift indels, inframe indels, missense mutations, nonsense mutations, nonstop mutations, and translation start site mutations.) B The domains and the corresponding mutation sites of SETD2 mutations. Domains and the corresponding mutation sites of the SETD2 gene identified in the Geneplus cohort. Green, red, blue, brown, orange, and purple dots represent Missense_Mutation, Nonsense_Mutation, Frame_Shift_Del, In_Frame_Del, Splice_Site, and Frame_Shift_Ins, respectively. C Proportion of SETD2 mutation forms by cohort and cancer type

The correlation between SETD2 deleterious mutation and tumor mutation burden

Since SETD2 is a crucial element for maintaining genomic stability [35], we assumed that a SETD2 deleterious mutation may lead to higher levels of TMB. The TMB of a total of 6721 patients form different cancer types was calculated and the TMB was compared between SETD2 mut + and SETD2 mut- groups. We found that the TMB levels in different tumors were stratified by SETD2 mutation status. We observed a significantly higher TMB level in SETD2 mut + in colorectal cancer (P < 0.001), NSCLC (P < 0.001), melanoma (P = 0.0022), glioma (P = 0.0042), and pancreatic cancer (P = 0.00012) (Fig. 2A). As TMB is considered a favorable biomarker for ICI treatment, it is highly likely that SETD2mutations can also serve as a prognostic factor for ICIs therapy [36].

Fig. 2
figure 2

A Correlation between SETD2 deleterious mutations and TMB. The difference of TMB in patients with SETD2 deleterious mutations and non-deleterious mutations across different cancer types in the GenePlus cohort. B Difference of tumor mutation burden (TMB) in patients with diverse molecular features (SETD2 deleterious mutations, BRCA1/2 deleterious mutations, MMR genes deleterious mutations, or POLE/D1 deleterious mutations) from the GenePlus cohort (Wilcoxon rank-sum test; ****, P < 0.0001; ***, P < 0.001; **, P < 0.01; *, P < 0.05.)

To evaluate the effects of DDR-related mutations on TMB status, we further examined the TMB level in tumors with such mutations. The results showed no significant difference in TMB in samples comparing SETD2 mutants to BRCA1/2, MMR, and POLE/D1 mutant genes in colorectal cancer, glioma, hepatic carcinoma, NSCLC, renal cell carcinoma, and melanoma (Fig. 2B). Given that tumor mutation load is a consequence of the rates of mutagenesis and DDR, higher TMB and activation of the DDR system might be consistent with a more drastic mutagenesis in patients with deleterious SETD2 mutations. We additionally investigated the change to DDR pathways resulting from SETD2 dysfunctional mutations. The results showed upregulation in DDR pathways including HRR, MMR, nucleotide excision repair (NER), Fanconi anemia pathway (FA), translesion DNA synthesis (TLS), nonhomologous end-joining (NHEJ), and checkpoint factors (CPF), demonstrating a compensatory activation in DDR pathways due to a SETD2 mutation (Figure S1).

The correlation between SETD2 deleterious mutations and microsatellite status

As microsatellite status represent the phenotype of genomic instability, we next investigated the correlation between SETD2 deleterious mutations and replication slippage variants at microsatellite regions. MSIsensor [25] is a tool developed for determining the MSI status by quantifying the percentage of unstable microsatellites. We downloaded the MSIsensor scores of TCGA pan-cancer samples from Mandal R. et al. [26]. A MSIsensor score ≥ 4 was denoted as MSH-H [27, 28]. Wilcoxon rank-sum tests showed that the SETD2 mut + group had a significantly higher MSIsensor score than that the SETD2 mut- group in endometrial carcinoma, colorectal adenocarcinoma, and stomach adenocarcinoma (Fig. 3A). Since MSH2, MSH6, MLH1, and PMS2 are critical for MMR, mutations in any of these genes can cause MSI-H. We then evaluated MSIsensor scores among MLH1 mut + , MSH2 mut + , MSH6 mut + , and PSM2 mut + groups and compared to the SETD2 mut + group (Figure S2A). The results showed no significant differences in MSIsensor score between patients who bore alterations within these genes. Further analysis showed that a SETD2 deleterious mutation was an independent factor influencing MSI-H in colorectal carcinoma (P < 0.0001) and stomach adenocarcinoma (P = 0.003) (Fig. 3B). Preclinical data showed that SETD2-dependent histone H3K36 trimethylation is required for homologous recombination repair and genome stability [17]. However when exploring the potential effects of a SETD2 mutation on homologous recombination pathways, we observed a decreased HRD score in the SETD2 mut + group compared to the SETD2 mut- group in endometrial carcinoma, colorectal adenocarcinoma, and stomach adenocarcinoma. (Fig. 3C).

Fig. 3
figure 3

Correlation between SETD2 deleterious mutations, MSI, and HRD. A Differences in MSIsensor scores in patients with SETD2 deleterious mutations and non-deleterious mutations in the TCGA cohort across seven cancer types. B Odds ratios and 95% confidence intervals calculated by multivariate binary logistic regression comparing the risk of MSI-H (MSIsensor score ≥ 4) for patients with and without mutated genes in endometrial carcinoma, colorectal carcinoma, and stomach adenocarcinoma. C Differences in HRD scores in patients with SETD2 deleterious mutations and non-deleterious mutations in the TCGA cohort across seven cancer types

The correlation between SETD2 deleterious mutations and an inflamed tumor microenvironment

A SETD2 mutation tends to cause a higher level of TMB and MSI, which may lead to an inflamed immune signature. Therefore, we next estimated the fraction of infiltrating immune cells as well as immune and stromal components using the CIBERSORT (Fig. 4A) algorithm and ESTIMATE, respectively, to analyze the TCGA database. The results exhibited a significantly increased fraction of memory and activated CD8 and CD4 T-cells, activated NK cells and M1 macrophages, and a significant decrease in M0 and M2 macrophages in the SETD2 mut + group (Fig. 4A). There was also a higher immune score in the SETD2 mut + group in colorectal adenocarcinoma, renal cell carcinoma, and endometrial carcinoma (Figure S3). Immune gene clusters were upregulated, including checkpoint (PDCD1 and LAG3), cytotoxic lymphocyte (GZMA, GZMB, CD8A, and PRF1), Th1 (IFNG and TBX21), anti-tumor chemokines (CXCL9), and pro-tumor chemokines (CCL3) (Fig. 4B, Table S3). This revealed that a SETD2 deleterious mutation was associated with a more inflamed tumor microenvironment in patients with renal cell carcinoma (Figure S4A), colorectal adenocarcinoma (Figure S4B), and endometrial carcinoma (Figure S4C).

Fig. 4
figure 4

Tumors with SETD2 deleterious mutations exhibit an inflamed immune microenvironment. A Different fractions of seven types of immune cells estimated by the CIBERSORT deconvolution algorithm between SETD2 deleterious mutation and SETD2 non-deleterious mutation groups. Samples were taken from patients across seven types of cancer in the TCGA cohort (bladder urinary cancer, colorectal adenocarcinoma, renal carcinoma, NSCLC, skin cutaneous melanoma, stomach adenocarcinoma, and endometrial carcinoma) (N = 2360). B Comparison of the expression of immune-related gene profiles between the SETD2 non-deleterious mutation group and the deleterious mutation group. Samples were taken from patients across seven cancer types in the TCGA cohort (bladder urinary cancer, colorectal adenocarcinoma, renal carcinoma, NSCLC, skin cutaneous melanoma, stomach adenocarcinoma, and endometrial carcinoma)

The correlation between deleterious SETD2 mutations and response to ICIs

Herein, we investigate the survival outcome of patients with or without SETD2 mutations who underwent ICI treatment. A 6726 Chinese pan-cancer population with 375 patients who had SETD2 mutations was retrospectively analyzed (Table S1). Unfortunately, 362 patients were excluded due to 1) only receiving one to three cycles ICIs treatment, 2) incomplete imaging data, 3) incomplete follow-up data, or 4) a benign tumor. The remaining patients who met our criteria had been diagnosed with lung adenocarcinoma (9/13), lung sarcomatous carcinoma (1/13), ovarian cancer (1/13), renal cell carcinoma (1/13), or urothelium carcinoma (1/13) (Table S4). Among these patients, seven were treated with mono-ICIs, three were treated with ICIs and chemotherapy, and three were treated with ICIs and target therapy. The disease course of two patients showed an exceptional response to ICI treatment, as shown in Figure S5. The median OS and PFS of the 13 patients were 18 months and 8 months (Fig. 5A), respectively, or 18 months and 7 months, respectively, for PD-1/PD-L1 monotherapy. The overall response rates (ORRs) were 42.9% (3/7) for PD-1/PD-L1 monotherapy and 53.8% (7/13) for all patients (Fig. 5B), which is better than ORR for non-selective cancer patients (15%–35%) [37,38,39,40,41,42]. The disease control rates (DCRs) were 92.3% (12/13) for all patients and 85.7% (6/7) for PD-1/PD-L1 monotherapy (Fig. 5B). The mutational sites were scattered throughout the whole gene (Fig. 5C), and the details are shown in Fig. 5D. This phenomenon was validated by the results, which revealed a significantly better (P < 0.0001) OS in SETD2 mut + than that in SETD2 mut- patients (Fig. 5E). Multivariate analysis with the adjustment for TMB, MMR gene mutations, and POLE/D1 mutations also showed that SETD2 deleterious mutations were an independent factor influencing ICI efficacy (Table S5) and the hazard ration was much lower in SETD2 deleterious mutation group than TMB-H (0.511 vs 0.757). These results indicate a potential tissue prognostic role of SETD2 deleterious mutations in ICI-treated patients.

Fig. 5
figure 5

A Overall survival (OS) and progression free survival (PFS) curves of immune checkpoint inhibitor (ICI)-treated patients. B ORR rates and DCR rates of patients with PD-1/PD-L1 inhibitor monotherapy, or combined therapy with other drugs. C Mutation sites and types of SETD2 mutation in ICI-treated patients. D Response evaluation criteria in solid tumors (PR, partial response; SD, stable disease; PD, progression disease), cancer types, SETD2 mutation status, and treatment types of GenePlus ICI-treated patients. E SETD2 deleterious mutations are linked with improved survival outcome in the ICI-treatment cohort

Discussion

This study aimed to determine whether SETD2 dysfunction is a complementary or independent factor of MSH-H and TMB, and whether this type of dysfunction acts differently in various types of cancer.

In this study, we investigated the mutation distribution in detail and found that mutations were scattered throughout the SETD2 gene without accumulating in any specific area. To better understand the impact of SETD2 dysfunction, analysis of cases with deleterious SETD2 mutations were applied in this study.

As a DDR-related gene, SETD2 ensures precise DNA replication. Accumulating evidence had shown that mutations in DDR-related genes, such as MSH2, MSH6, PMS2, MLH1, BRCA1/2, and POLE/D1, which function in MMR, HRR, and BER, are the main reasons for higher TMB and an immunogenic response [43,44,45,46]. In our study, we found a parallel tendency of a TMB increase between SETD2 deleterious mutations and DDR gene mutations including BRCA1/2, MMR genes, and POLE/D1 across seven cancer types. Our multi-cox regression analysis showed that SETD2 deleterious mutations (distinct from BRCA1/2, MMR genes, and POLE/D1) were an independent factor influencing OS with adjustment for TMB, and an even lower death hazard ratio following ICI treatment was found in the SETD2 deleterious mutation group compared with TMB-H patients. The deletion of SETD2 can result in accumulation of DNA damage and impaired cellular tolerance towards replication stress through either loss of SETD2 function or dysregulation of recruitment and activation of early DDR factors like ATM, p53, and RAD51, explaining the correlation between SETD2 mutation and TMB elevation [18].

FDA approved MSI-H detected by polymerase chain reaction or dMMR detected by immunohistochemistry with any deficiency of MSH2, MSH6, PMS2 and MLH1 as biomarker for immunocheckpoint treatments. Preclinical data showed that in Hela cells, H3K36me3 converted by SETD2 from H3K36me2 recruits hMutSa onto chromatin via its interaction with the hMSH6 PWWP domain before DNA replication initiates. During DNA replication, H3K36me3-PWWP interaction was disrupted and released hMutSa which can quickly identify the mismatch to initiate the MMR reaction [16]. We found that MSH2, MSH6, MLH1, PMS2 and SETD2 independently influencing MSI-H in endometrial carcinoma, colorectal adenocarcinoma, and stomach adenocarcinoma patients. This finding was a confirmation of preclinical data and identify a distinct role of SETD2 between endometrial carcinoma, colorectal adenocarcinoma, stomach adenocarcinoma and bladder urinary cancer, renal carcinoma, NSCLC, melanoma.

HRD is an index for measuring functional defects in homologous recombination DNA repair, deriving from germline or somatic mutations in BRCA1/2 function or other mechanisms [47]. Preclinical data showed that SETD2 is required for HRR, however we observed unimpaired HRR in certain types of cancers in SETD2 deleterious mutant samples. For synthetical lethal was found in cells with deficient of both BER and HRR deficient patients we postulate that tumors cells with deficient in both MMR and HRR will undergo cell death but further scientific evidence is needed to confirm this conjecture [48]. The remaining tumor cells that harbor mutations in one repair pathway would, consequently, have a lower HRD score. Meanwhile, the dysfunction of HRR is considered to be a biomarker for PARPi and platinum-based chemotherapy. Therefore, these results indicate that ICI treatment rather than chemotherapy or target therapy may be more suitable for endometrial carcinoma, colorectal adenocarcinoma, and stomach adenocarcinoma patients with SETD2 mutations.

Extrinsic and intrinsic immune escape is crucial in tumorigenesis and cancer progression. Four reasons account for extrinsic immune escape: lack of immune cells, presence of immunoinhibitory cells, such as type 2 macrophages and regulatory T-cells (Treg); high concentrations of immunoinhibitory cytokines, such as interleukin 10 (IL10) and transforming growth factor β (TGF-β); and fibrosis [49]. Also, it is known that at least two aspects, including tumor immunogenicity and expression of immune checkpoint molecules, are responsible for intrinsic immune escape [50]. When analyzing pooled data from patients with different cancer types, our results showed higher levels of infiltrating of CD8 cells, lower levels of infiltrating of M2 macrophages, higher TMB, and higher expression of immune checkpoint molecules in the SETD2 deleterious mutation group. This may be the underlying mechanism for a favorable ICI response in this group. When comparing the differences across cancer types, our results showed that a more inflamed tumor microenvironment was present in the SETD2 deleterious mutation group in colorectal carcinoma, endometrial carcinoma, and renal cell carcinoma. The data above illustrate the underlying mechanisms for the favored ICI response in the SETD2 deleterious mutation group.

By analyzing our 13 patients with ICI treatment, we found a better ORR in these patients than in non-selective cancer patients treated with immunotherapy. Furthermore, we verified that SETD2 deleterious mutations may have the potential to serve as a biomarker for ICI therapy. Although the survival advantage has been shown in the MSKCC-IO cohort, there are limitations to using local cohorts for survival analysis like the insufficient sample size, lack of control group and the combined treatment which can’t rule out the possibility that the survival benefit of SETD2 mutation may result from chemotherapy or tyrosine kinase inhibitors; as such, a large randomized prospective study will be needed to further test our hypothesis. Additionally, the specific pathway through which SETD2 affects prognosis is not made clear in our study; therefore, in vivo and in vitro experiments are needed.

This study is of great importance. First, with respect to response, MSH-H/dMMR performed far better than other biomarkers, with ORR reaching 53% compared with just 29% in TMB-H patients. Based on our finding that SETD2 influences MSI-H with the adjustment of MMR related proteins, we recommend that SETD2 should be considered when testing MMR function by IHC (in addition to the classical MSH2, MSH6, MLH1, and PMS2 screening). This will screen for more groups that may benefit from ICI treatment. Second, TMB has been approved by the FDA as a tissue agnostic biomarker for ICI treatment. We found that SETD2 influences survival outcome independently of TMB following ICI treatment in pancancer patients, and also has a much lower death hazard compared to TMB. Third, although preclinical data has shown that SETD2 deficient cells have impaired MMR and HRR, we identified unimpaired HRR in endometrial carcinoma, colorectal adenocarcinoma, and stomach adenocarcinoma; this may be explained by possible synthetic lethality between impaired HRR and impaired MMR. Fourth, a SETD2 mutation rate greater than 5% was found in 10 cancer types, indicating that a large population of patients may benefit from ICI treatment. Taken together, our data demonstrate that SETD2 should be given more attention as a candidate biomarker for ICI treatment.

Conclusion

Based on our finding that SETD2 dysfunction affects ICI treatment prognosis independently of TMB-H and has a lower death hazard than TMB-H in pancancer patients, SETD2 has the potential to serve as a biomarker for ICI treatment. Additionally, in endometrial carcinoma, colorectal adenocarcinoma, and stomach adenocarcinoma, SETD2 should be considered when dMMR is detected by immunohistochemistry.

Availability of data and materials

The data supporting the conclusions of this article are included within the article and the additional files. The original case report forms and other related datasets are available from the corresponding author on reasonable request.

References

  1. Tang J, Shalabi A, Hubbard-Lucey VM. Comprehensive analysis of the clinical immuno-oncology landscape. Ann Oncol. 2018;29(1):84–91.

    Article  CAS  PubMed  Google Scholar 

  2. Couzin-Frankel J. Breakthrough of the year 2013. Cancer immunotherapy. Science. 2013;342(6165):1432–3.

    Article  CAS  PubMed  Google Scholar 

  3. Ribas A, Wolchok JD. Cancer immunotherapy using checkpoint blockade. Science. 2018;359(6382):1350–5.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  4. Le DT, Durham JN, Smith KN, et al. Mismatch repair deficiency predicts response of solid tumors to PD-1 blockade. Science. 2017;357(6349):409–13.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  5. Weber JS, Hodi FS, Wolchok JD, et al. Safety profile of nivolumab monotherapy: a pooled analysis of patients with advanced melanoma. J Clin Oncol. 2017;35(7):785–92.

    Article  CAS  PubMed  Google Scholar 

  6. Bertrand A, Kostine M, Barnetche T, Truchetet M-E, Schaeverbeke T. Immune related adverse events associated with anti-CTLA-4 antibodies: systematic review and meta-analysis. BMC Med. 2015;13:211.

    Article  PubMed  PubMed Central  Google Scholar 

  7. Wolchok JD, Chiarion-Sileni V, Gonzalez R, et al. Overall survival with combined nivolumab and ipilimumab in advanced melanoma. N Engl J Med. 2017;377(14):1345–56.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  8. Gibney GT, Weiner LM, Atkins MB. Predictive biomarkers for checkpoint inhibitor-based immunotherapy. Lancet Oncol. 2016;17(12):e542–51.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  9. Bonneville R, Krook MA, Kautto EA, et al. Landscape of microsatellite instability across 39 cancer types. JCO Precis Oncol. 2017;2017:PO.17.00073.

    PubMed  Google Scholar 

  10. Marabelle A, Fakih M, Lopez J, et al. Association of tumour mutational burden with outcomes in patients with advanced solid tumours treated with pembrolizumab: prospective biomarker analysis of the multicohort, open-label, phase 2 KEYNOTE-158 study. Lancet Oncol. 2020;21(10):1353–65.

    Article  CAS  PubMed  Google Scholar 

  11. Mouw KW, Goldberg MS, Konstantinopoulos PA, D’Andrea AD. DNA damage and repair biomarkers of immunotherapy response. Cancer Discov. 2017;7(7):675–93.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  12. Chen Y, Chen G, Li J, et al. Association of tumor protein p53 and ataxia-telangiectasia mutated comutation with response to immune checkpoint inhibitors and mortality in patients with non-small cell lung cancer. JAMA Netw Open. 2019;2(9):e1911895.

    Article  PubMed  PubMed Central  Google Scholar 

  13. Campbell BB, Light N, Fabrizio D, et al. Comprehensive analysis of hypermutation in human cancer. Cell. 2017;171(5):1042-1056. e10.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  14. Mehnert JM, Panda A, Zhong H, et al. Immune activation and response to pembrolizumab in POLE-mutant endometrial cancer. J Clin Invest. 2016;126(6):2334–40.

    Article  PubMed  PubMed Central  Google Scholar 

  15. Huang Y, Gu L, Li GM. H3K36me3-mediated mismatch repair preferentially protects actively transcribed genes from mutation. J Biol Chem. 2018;293(20):7811–23.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  16. Li F, Mao G, Tong D, et al. The histone mark H3K36me3 regulates human DNA mismatch repair through its interaction with MutSalpha. Cell. 2013;153(3):590–600.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  17. Pfister SX, Ahrabi S, Zalmas LP, et al. SETD2-dependent histone H3K36 trimethylation is required for homologous recombination repair and genome stability. Cell Rep. 2014;7(6):2006–18.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  18. Carvalho S, Vitor AC, Sridhara SC, et al. SETD2 is required for DNA double-strand break repair and activation of the p53-mediated checkpoint. Elife. 2014;3:e02482.

    Article  PubMed  PubMed Central  Google Scholar 

  19. Dalgliesh GL, Furge K, Greenman C, et al. Systematic sequencing of renal carcinoma reveals inactivation of histone modifying genes. Nature. 2010;463(7279):360–3.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  20. Chen R, Zhao W-Q, Fang C, Yang X, Ji M. Histone methyltransferase SETD2: a potential tumor suppressor in solid cancers. J Cancer. 2020;11(11):3349–56.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  21. Hutter C, Zenklusen JC. The cancer genome atlas: creating lasting value beyond its data. Cell. 2018;173(2):283–5.

    Article  CAS  PubMed  Google Scholar 

  22. Samstein RM, Lee CH, Shoushtari AN, et al. Tumor mutational load predicts survival after immunotherapy across multiple cancer types. Nat Genet. 2019;51(2):202–6.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  23. Zehir A, Benayed R, Shah RH, et al. Mutational landscape of metastatic cancer revealed from prospective clinical sequencing of 10,000 patients. Nat Med. 2017;23(6):703–13.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  24. Zehir A, Benayed R, Shah RH, et al. Mutational landscape of metastatic cancer revealed from prospective clinical sequencing of 10,000 patients. Nat Med. 2017;23(6):703–13.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  25. Niu B, Ye K, Zhang Q, et al. MSIsensor: microsatellite instability detection using paired tumor-normal sequence data. Bioinformatics. 2014;30(7):1015–6.

    Article  CAS  PubMed  Google Scholar 

  26. Mandal R, Samstein RM, Lee K-W, et al. Genetic diversity of tumors with mismatch repair deficiency influences anti-PD-1 immunotherapy response. Science. 2019;364(6439):485–91.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  27. Bailey MH, Tokheim C, Porta-Pardo E, et al. Comprehensive Characterization of Cancer Driver Genes and Mutations. Cell. 2018;173(2):371-385 e318.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  28. Ding L, Bailey MH, Porta-Pardo E, et al. Perspective on oncogenic processes at the end of the beginning of cancer genomics. Cell. 2018;173(2):305-320 e310.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  29. Thorsson V, Gibbs DL, Brown SD, et al. The Immune Landscape of Cancer. Immunity. 2018;48(4):812-830 e814.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  30. Newman AM, Liu CL, Green MR, et al. Robust enumeration of cell subsets from tissue expression profiles. Nat Methods. 2015;12(5):453–7.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  31. Yoshihara K, Shahmoradgoli M, Martinez E, et al. Inferring tumour purity and stromal and immune cell admixture from expression data. Nat Commun. 2013;4:2612.

    Article  PubMed  Google Scholar 

  32. Li B, Dewey CN. RSEM: accurate transcript quantification from RNA-Seq data with or without a reference genome. BMC Bioinformatics. 2011;12(1):323.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  33. Barbie DA, Tamayo P, Boehm JS, et al. Systematic RNA interference reveals that oncogenic KRAS-driven cancers require TBK1. Nature. 2009;462(7269):108–12.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  34. Core Team R. R: a language and environment for statistical computing. Vienna: R Foundation for statistical computing; 2013.

    Google Scholar 

  35. Kim T-M, Laird PW, Park PJ. The landscape of microsatellite instability in colorectal and endometrial cancer genomes. Cell. 2013;155(4):858–68.

    Article  CAS  PubMed  Google Scholar 

  36. Marabelle A, Fakih M, Lopez J, et al. Association of tumour mutational burden with outcomes in patients with advanced solid tumours treated with pembrolizumab: prospective biomarker analysis of the multicohort, open-label, phase 2 KEYNOTE-158 study. Lancet Oncol. 2020;21(10):1353–65.

    Article  CAS  PubMed  Google Scholar 

  37. Herbst RS, Baas P, Kim D-W, et al. Pembrolizumab versus docetaxel for previously treated, PD-L1-positive, advanced non-small-cell lung cancer (KEYNOTE-010): a randomised controlled trial. Lancet. 2016;387(10027):1540–50.

    Article  CAS  PubMed  Google Scholar 

  38. Muro K, Chung HC, Shankaran V, et al. Pembrolizumab for patients with PD-L1-positive advanced gastric cancer (KEYNOTE-012): a multicentre, open-label, phase 1b trial. Lancet Oncol. 2016;17(6):717–26.

    Article  CAS  PubMed  Google Scholar 

  39. Weber JS, D’Angelo SP, Minor D, et al. Nivolumab versus chemotherapy in patients with advanced melanoma who progressed after anti-CTLA-4 treatment (CheckMate 037): a randomised, controlled, open-label, phase 3 trial. Lancet Oncol. 2015;16(4):375–84.

    Article  CAS  PubMed  Google Scholar 

  40. Ferris RL, Blumenschein G, Fayette J, et al. Nivolumab for recurrent squamous-cell carcinoma of the head and neck. N Engl J Med. 2016;375(19):1856–67.

    Article  PubMed  PubMed Central  Google Scholar 

  41. Larkin J, Hodi FS, Wolchok JD. Combined nivolumab and ipilimumab or monotherapy in untreated melanoma. N Engl J Med. 2015;373(13):1270–1.

    Article  PubMed  Google Scholar 

  42. Motzer RJ, Escudier B, McDermott DF, et al. Nivolumab versus everolimus in advanced renal-cell carcinoma. N Engl J Med. 2015;373(19):1803–13.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  43. Tomasova K, Cumova A, Seborova K, et al. DNA repair and ovarian carcinogenesis: impact on risk, prognosis and therapy outcome. Cancers (Basel). 2020;12(7):1713.

    Article  CAS  PubMed  Google Scholar 

  44. Cleary JM, Aguirre AJ, Shapiro GI, D’Andrea AD. Biomarker-Guided Development of DNA Repair Inhibitors. Mol Cell. 2020;78(6):1070–85.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  45. Park VS, Pursell ZF. POLE proofreading defects: Contributions to mutagenesis and cancer. DNA Repair. 2019;76:50–9.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  46. Nicolas E, Golemis EA, Arora S. POLD1: Central mediator of DNA replication and repair, and implication in cancer and other pathologies. Gene. 2016;590(1):128–41.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  47. Turner N, Tutt A, Ashworth A. Hallmarks of “BRCAness” in sporadic cancers. Nat Rev Cancer. 2004;4(10):814–9.

    Article  CAS  PubMed  Google Scholar 

  48. Basu B, Sandhu SK, de Bono JS. PARP inhibitors: mechanism of action and their potential role in the prevention and treatment of cancer. Drugs. 2012;72(12):1579–90.

    Article  CAS  PubMed  Google Scholar 

  49. Spranger S. Mechanisms of tumor escape in the context of the T-cell-inflamed and the non-T-cell-inflamed tumor microenvironment. Int Immunol. 2016;28(8):383–91.

    Article  CAS  PubMed  Google Scholar 

  50. Schreiber RD, Old LJ, Smyth MJ. Cancer immunoediting: integrating immunity’s roles in cancer suppression and promotion. Science. 2011;331(6024):1565–70.

    Article  CAS  PubMed  Google Scholar 

Download references

Acknowledgements

We appreciate all subjects who participated in this study.

Funding

Joint Funds for the Innovation of Science and Technology, Fujian province (Grant No. 2021Y9227)

Joint Funds for the innovation of science and Technology, Fujian province(Grant number. 2020Y9040)

Fujian provincial health technology project (Grant NO. 2022ZD01005)

Fujian Provincial Clinical Research Center for Cancer Radiotherapy and Immunotherapy (Grant number. 2020Y2012)

The Science Foundation for The Excellent Youth Scholars of Fujian Provincial Health Commission (No. 2022ZQNZD009)

Author information

Authors and Affiliations

Authors

Contributions

C.B.C, Y.C, and X.B.Z conceived and supervised the study. X.B.Z., J.L, J.N.X., and Y.C. wrote the manuscript. B.L, L.C, Y.L, Y.F.G, J.L., L.C., L.Z.C., Z.D.F., L.S., W.G.C., X.H.A., C.Z.Z., X.F.L., J.Z., X.T.Y, Z.Q.G, Q.T.Y, and G.C. collected clinical data on the GenePlus cohort. X.B.Z., X.G., X.Y., and Y.L. performed statistical analysis and drew pictures. All authors have read and approved the manuscript.

Corresponding authors

Correspondence to Yu Chen or Chuanben Chen.

Ethics declarations

Ethics approval and consent to participate

All procedures were conducted in accordance with the Declaration of Helsinki and with approval from the ethics committee of Fujian Provincial Cancer Hospital. Written informed consent was obtained from all participants.

Consent for publication

Not applicable.

Competing interests

The authors declare no competing interests.

Additional information

Publisher’s Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Supplementary Information

Rights and permissions

Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated in a credit line to the data.

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Zheng, X., Lin, J., Xiong, J. et al. SETD2 variation correlates with tumor mutational burden and MSI along with improved response to immunotherapy. BMC Cancer 23, 686 (2023). https://doi.org/10.1186/s12885-023-10920-4

Download citation

  • Received:

  • Accepted:

  • Published:

  • DOI: https://doi.org/10.1186/s12885-023-10920-4

Keywords