Clinicopathological and biological significance of cripto overexpression in human colon cancer.

Aim: To assess the clinicopathological and biological significance of cripto in human colorectal cancer.

Methods: Real-time reverse-transcription polymerase chain reaction (PCR) was used to examine cripto mRNA levels in primary colon cancer and normal colon tissues as well as normal and metastatic lymph nodes from colon cancers. Human colon cancer LS-174T cells were transfected with cripto small interfering RNA (siRNA), and mRNA and protein levels were evaluated using real-time PCR and western blot analysis, respectively. The growth of cancer cells was evaluated using the MTT assay and colony formation in soft agar. Invasion was examined using a Transwell assay, and the expressions of matrix metalloproteinase (MMP)-7 and MMP-9 were determined using western blot assay.

Results: Cripto was significantly overexpressed in primary colon cancer and metastatic lymph nodes. Silencing cripto gene expression with cripto siRNA resulted in a significant decrease in colony formation in soft agar in the colon cancer cell line LS-174T. Cripto siRNA treatment decreased the migration and invasion capabilities of the colon cancer cell line LS-174T in vitro. Furthermore, cripto siRNA treatment inhibited the expression of matrix MMP-7 and MMP-9.

Conclusion: The results provide evidence that cripto siRNA could be an effective approach for the inhibition of cancer cell invasion and migration and thus has potential for use in devising novel preventive and therapeutic strategies for colon cancer metastasis.