Figure 1.

Inverse correlation of miR‐497 and VEGF ‐A expression in clinical CRC samples. miR‐497 and VEGF‐A mRNA expression in 34 pairs of primary CRC samples and the corresponding non‐malignant colorectal tissues (NT) (frozen samples). (a) miR‐497 expression levels were calculated using miR‐497/U6 expression ratio (2^−Δct). Median miR‐497 expression levels in normal colorectal tissue (NT) and primary CRC were 21.06 and 4.372 respectively. miR‐497 expression was significantly lower in primary CRC samples relative to the NT tissue expression levels (P < 0.001). (b) miR‐497 expression levels in primary CRC samples relative to their corresponding NT tissue samples. Log₂ fold change was considered significant overexpression or down‐regulation. miR‐497 expression was found to be reduced in 91% (31 of 34) of the CRC cases examined. (c) VEGF‐A mRNA expression levels were calculated as the VEGF‐A/GAPDH expression ratio (i.e. 2^−Δct). Median VEGF‐A mRNA expression levels in normal colorectal tissue (NT) and primary CRC tissues were 0.1894 and 27.86 respectively. VEGF‐A expression was significantly up‐regulated in primary CRC samples compared to corresponding NT tissue (P < 0.001). (d) VEGF‐A mRNA expression levels in primary CRC samples relative to their corresponding NT tissue samples. Log₂ fold change was considered as significant overexpression. VEGF‐A mRNA was found to be up‐regulated in 100% (34 of 34) of the CRC cases examined. (e) A correlation analysis performed using Pearson's χ² test in 18 pairs of clinical CRC specimens suggests a negative correlation between the expression of miR‐497 and VEGF‐A.