Figure 1

mRNA expression analysis of chemokine receptors in osteosarcoma tumor biopsies and bone precursors. The open black circles indicate values of chemokine receptor expression of mRNA isolates from osteosarcoma biopsy samples with each circle representing the value of a single sample. Red Triangles indicate the mRNA expression of the osteoblastoma. Median values of at least three independent RNA preparations are represented by green hyphens for primary MSC, undifferentiated (orange cross) and differentiated osteoblasts (blue X). The grey field indicates borderline detectable expression values, defined as CT values between 38 and 40 cycles. All values below are rated as negative values (nd = not detectable). The y-axis represents expression levels normalized vs. rRNA. On the x-axis the chemokine receptors are indicated. CCR1, CCR2, CCR5, CCR7, CXCR4, CXCR5 and CX3CR1 are expressed in all of the tested samples. CCR4 is expressed in 21/22 tumors. CXCR3 is only detectable in a fraction of the tested samples and CCR10 is either borderline or not detectable. The overall receptor expression is higher in the tumor than in the bone precursors. The benign bone tumor (osteoblastoma) demonstrates expression values that are close to those of the sarcoma tissue.