Apatinib inhibits paclitaxel resistance of gastric carcinoma cells through VEGFR2 pathway

Abstract

Drug resistance of gastric carcinoma (GC) is a burning question in the medical field. This study aimed to investigating the ameliorative effect of apatinib (Apa) on paclitaxel (PTX) resistance in GC. In this research, PTX-resistant MGC803 cells were intervened by Apa. Cell proliferation was detected by cell counting kit-8 (CCK-8) assay, and cell migration and invasion was determined by Transwell assays. The levels of apoptosis-related proteins (Bcl-2, Bax), drug resistance-related proteins (MDR1, P-gp) and VEGFR2 protein were measure by Western blot, and the mRNA expression of VEGFR2 was tested by real-time quantitative polymerase chain reaction (RT-qPCR). Then VEGFR2 was overexpressed to examine the role of Apa in PTX-resistant MGC803 cells. The results identified a significantly reduced growth rate of MGC803/PTX cells after PTX induction, obviously increased invasive and migrated cells, and evidently enhanced proliferation capacity of MGC803/PTX cells as compared to MGC803 cells. In MGC803/PTX cells, VEGFR2, MDR1, P-gp and Bcl-2 were all up-regulated while Bax was down-regulated. After Apa intervention, PTX-resistant MGC803 cells showed decreased cell migration, invasion and proliferation, reduced MDR1, P-gp and VEGFR2 levels, and increased Bax protein level. Overexpression of VEGFR2 can offset the rescue effect of Apa on PTX-induced drug resistance of MGC803 cells. Taken together, Apa may inhibit PTX resistance of MGC803 cells via the VEGFR2 signaling pathway.

Keywords: Apatinib; VEGFR2; gastric carcinoma; paclitaxel; tumor resistance.

Figure 1

Establishment of drug-resistant human GC cell line MGC803/PTX. A: IC50 value and drug resistance index of PTX to MGC803 cells and MGC803/PTX cells; B: Growth curve of MGC80 parent cells and drug-resistant cells. *P<0.05 vs MGC803 cells.

Figure 2

Proliferation, invasion and migration of MGC803 cells and MGC803/PTX cells. A: Number of clone formation of MGC803 cells and MGC803/PTX cells; B: Invasion and migration of MGC803 cells and MGC803/PTX cells; **P<0.01.

Figure 3

mRNA and protein expression of VEGFR2 in MGC 803 cells and MGC803/PTX cells. A: VEGFR2 mRNA expression; B: VEGFR2 protein expression; **P<0.01.

Figure 4

Expression of drug resistance- and apoptosis-related proteins in MGC 803 cells and MGC803/PTX cells. A: Western blot; B: Expression of related proteins; **P<0.01.

Figure 5

Selection of Apa concentration.

Figure 6

Effects of Apa on proliferation, invasion and migration of MGC803/PTX cells. A: Number of clone formation of MGC803/PTX cells; B: Number of invasion and migration of MGC803/PTX cells; *P<0.05, **P<0.01.

Figure 7

Effects of Apa on mRNA and protein expression of VEGFR2 in MGC803/PTX cells. A: VEGFR2 mRNA expression; B: VEGFR2 protein expression; *P<0.05, **P<0.01.

Figure 8

Effects of Apa on expression of drug resistance- and apoptosis-related proteins in MGC803/PTX cells. A: Western blots; B: MDR1 and P-pg protein expression; C: Bcl-2 and Bax protein expression; *P<0.05, **P<0.01.

Figure 9

Effects of Apa on MGC803/PTX cells overexpressing VEGFR2. A: VEGFR2 mRNA expression; B: VEGFR2 protein expression; C: Growth curves of VEGFR2-overexpressing MGC803/PTX cells treated with different concentrations of Apa. *P<0.05, **P<0.01, ***P<0.001.