Combination of Selected MET and EGFR Inhibitors Decreases Melanoma Cells’ Invasive Abilities

Abstract

We have previously shown that combination of foretinib, an inhibitor of MET (hepatocyte growth factor receptor), with gefitinib or lapatinib, inhibitors of EGFR (epidermal growth factor receptor), has a synergistic cytotoxic effect on melanoma cells. However, there are cancer cells resistant to drugs’ treatment which are still able to invade. Thus, in this study, we examined the influence of these drugs on invasive abilities of melanoma cells. To investigate cell migration and invasion, Transwell inserts and wound healing assay were used. Cell viability was evaluated by XTT method, while invadopodia formation by immunocytochemistry. Level of phosphorylated Src kinase (pSrc) was verified by Western blot. Proteolytic activity of cells was analyzed using gelatin conjugated with fluorescein degradation assay and gelatin zymography. Combination of used inhibitors diminished cell movement, resulting in smaller distances covered by cells, and decreased the ratio of cells with ability to cross the Transwell inserts. These inhibitors induced changes in formation of invadopodia and actin cytoskeleton organization. Their application also decreased the level of pSrc kinase. Furthermore, used drugs led to reduction of proteolytic activity of examined cells. Our data support the idea that simultaneous targeting of EGFR and MET could be a promising therapeutic strategy inhibiting not only tumor cell growth but also its metastasis.

Characterization of Melanoma Cell Lines Resistant to Vemurafenib and Evaluation of Their Responsiveness to EGFR- and MET-Inhibitor Treatment

“…As we have previously shown, EGFR and MET seem to be promising targets for anti-melanoma combination therapy using small molecule inhibitors. Foretinib (F, MET inhibitor) and lapatinib (L, EGFR inhibitor) used simultaneously were able to synergistically decrease the viability of melanoma cells, and also significantly diminish the invasive abilities and proteolytic activity of these cells [10,11]. Here, we have demonstrated that resistant cells exhibit overexpression of both studied receptors, which also corresponds to the elevated rate of migration and invasion.…”

“…Taking into account the overexpression and increased activation of RTKs in generated resistant cells, priming these molecules as potential therapy targets, we tested the efficiency of combination treatment using inhibitors of EGFR (lapatinib) and MET (foretinib) in this model. In our previous work, we have already demonstrated that dual inhibition of EGFR/MET was able to elicit a synergistic cytotoxic effect in melanoma cell lines, accompanied by a decrease in their invasive abilities [10,11]. Herein, we analyzed the effectiveness of a proposed therapy in A375 and WM9 cell lines resistant to vemurafenib, and noticed that both models demonstrate similar responsiveness to RTKs inhibitors compared with parental lines in terms of reduction of viability.…”

“…In this study, we aimed to extend our previous work, where we tested a combination therapy directed against proteins frequently overexpressed in melanoma-EGFR (epidermal growth factor receptor) and MET (hepatocyte growth factor receptor)-in a panel of human melanoma cell lines and samples derived from patients. We obtained a synergistic cytotoxic effect in these lines, and observed a significant decrease in their invasive abilities upon inhibitor treatment [10,11]. To further examine the efficacy of the developed therapy, we generated cell lines resistant to vemurafenib treatment.…”

PARP1 as a Marker of an Aggressive Clinical Phenotype in Cutaneous Melanoma—A Clinical and an In Vitro Study

“…In our previous studies, we demonstrated that the WM1341D cell line exhibits lower invasive abilities than A375, WM9, and Hs294T cell lines [ 37 , 38 ]. Compared to other cells, WM1341D formed a lower number of invadopodia (adhesive structures with proteolytic activity), which are utilized by cancer cells to digest the extracellular matrix and invade tissue.…”

“…The smallest number of digesting cells as well as the lowest digestion area were observed in WM1341D cells. A375 and Hs294T cells digested to a greater extent than WM1341D [ 37 , 38 ]. Our current results indicate that the invasiveness of the examined melanoma cells correlated positively with the level of PARP1 in these cells.…”