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Table 1 Frequency of tumor initiating cells

From: Tyrosine kinase inhibitor SU11274 increased tumorigenicity and enriched for melanoma-initiating cells by bioenergetic modulation

Confidence intervals for 1/(stem cell frequency)
Rel3 Lower Estimate Upper
 Spheroid cells 84,848 33,233 13,016
 SU11274-treated spheroid cells 7208 3289 1501
M14 Lower Estimate Upper
 Spheroid cells 168,352 38,964 9018
 SU11274-treated spheroid cells 29,964 10,211 3479
  1. Human melanoma cells were cultured in non-adherent conditions for 7 days in the presence or absence of 1 μM SU11274. Cells were counted, diluted in 1:1 serum-free medium: ECM gel and injected s.c. (n = 4/each group). Following numbers were injected: 50,000; 10,000; 5000; 1000; 500; 100; 50 and 10 Rel3 cells, and 20,000; 2000; 200 and 20 M14 cells based on preliminary test of tumorigenicity. Stem cell frequency was calculated by ELDA analysis, p value was ≤ 10−5 for the Rel3 cells, and ≤ 0.05 for the M14 cells. The tumor take rate was significantly higher in the SU11274-treated cells: 3 out of 4 inoculations of 500 SU11274-treated EGFP-A375/Rel3 cells gave tumors in contrast to 0 out of 4 inoculations of the untreated cells. Similarly, 4 out of 4 inoculations of 2000 SU11274-treated M14 cells gave tumors in contrast to 0 out of 4 inoculations of the untreated M14 cells