Inhibition of YAP reverses primary resistance to EGFR inhibitors in colorectal cancer cells.

Mutant KRAS and BRAF are associated with primary EGFR inhibitor resistance in colorectal cancer (CRC). However, other biomarkers that could predict EGFR inhibitor resistance remain elusive. In the present study, immunoblotting and cell proliferation results revealed that yes‑associated protein (YAP), a downstream effector of the Hippo pathway, was positively associated with primary cetuximab resistance in CRC cells.

[Cultivation and characterization of tumor spheres generated from human colorectal cancer cell lines].

Objective: To study on the cultivation method for tumor spheres from colorectal cancer cell lines and identify whether resulting Colo205 spheroid cells display cancer stem cell characteristics.

Methods: Lovo, Colo205 and SW480 cells were seeded in serum free medium (SFM) with EGF and bFGF. Flow cytometry analysis, cell invasion assay and xenograft experiment were applied to examine the cell surface marker expression pattern, cell invasive ability and in vivo tumorigenicity of both Colo205 spheres and parental cells.

[The effect of Rac1 siRNA on the biological behaviors of gastrointestinal cancer cells].

Objective: To explore the effect of Rac1 siRNA on the expression of Rac1 and the biological behaviors of gastrointestinal cancer cells.

Methods: Rac1 siRNA was transfected into human gastric cancer cell line SGC803 and colorectal cancer cell line Lovo by lipofectamine 2000. The expression of Rac1 in these cell lines were detected by Western blot and RT-PCR after 48 hours of the transfection.