Cucurbitacin B Enhances the Anticancer Effect of Imatinib Mesylate Through Inhibition of MMP-2 Expression in MCF-7 and SW480 Tumor Cell Lines

The combination of medicinal plant extracts with known chemotherapeutics offers significant potential for the development of novel therapies in cancer disease. Cucurbitacin B (CuB) is one of the most potent and widely used members of cucurbitacin family and it is known to have important effects on several diseases including cancer. To determine whether CuB can enhance chemosensitivity to imatinib mesylate (IM), in the present study, the combined effects of CuB with IM on MCF-7 and SW480 cells were investigated. The cells were treated with CuB alone or in combination with IM and the results showed that the combination treatment synergistically inhibited cell proliferation and induced apoptosis. Furthermore, the combined effect of CuB and IM on matrix metalloproteinase-2 (MMP-2) gene expression, a member of MMP family which is responsible for the degradation of extracellular matrix was also evaluated. CuB increased the inhibitory effect of IM on MMP-2 expression synergistically in a dose dependent manner. The results suggest that CuB in combination with IM may serve as a potentially useful therapeutic strategy for patients with breast and colorectal cancer.