Study on Apatinib Inhibiting the Growth of Nasopharyngeal Carcinoma CNE-2Z Cells and Its Mechanism

OBJECTIVE To explore the inhibitory effect of apatinib on nasopharyngeal carcinoma CNE-2Z cells and its possible mechanism. METHODS Nasopharyngeal carcinoma CNE-2Z cells combined with different concentrations of apatinib(0, 0.5, 1, 2 μmol·L^-1) were co-cultured for 48 h, and defined as 0, 0.5, 1 and 2 μmol·L^-1 group, respectively. MTT method was used to detect cell growth inhibition rate. Annexin V-FITC/PI combined with flow cytometry were used to detect cell apoptosis rate. Western blotting was used to detect Bcl-2, Bax, caspase-3, caspase-9, PI3K, p-PI3K, Akt, p-Akt protein expression. RT-PCR was used to detect p-PI3K, p-Akt mRNA expression. According to different drugs, the nasopharyngeal carcinoma CNE-2Z cells were diveded into 4 groups:control group, apatinib group, 740YP group, apatinib+740 YP group, 48 h later, Annexin V-FITC/PI combined with flow cytometry were used to detect cells apoptosis rate, Western blotting was used to detect the expression of p-PI3K and p-Akt protein. RESULTS MTT test results showed that apatinib inhibited the proliferation of CNE-2Z cells in a concentration-dependent manner(P<0.05), and the half-inhibitory concentration(IC₅₀ value) of apatinib on nasopharyngeal carcinoma cells was 1.518 μmol·L^-1. Annexin-V/PI combined with flow cytometry showed that apatinib induced apoptosis of CNE-2Z cells in a concentration-dependent manner(P<0.05). The result of Western blotting showed that apatinib promoted the expression of Bax, caspase-3 and caspase-9 in a dose-dependent manner(P<0.05), and inhibited the expression of Bcl-2(P<0.05). Apatinib could inhibit the expression of p-PI3K and p-Akt proteins and mRNA(P<0.05), but has no effect on the expression of PI3K and Akt proteins. After cell culture for 48 h, the apoptosis rate of the control group was (10.5±0.96)%, the apatinib group was (25.3±1.67)%, the 740YP group was (6.30±0.52)%, the apatinib+740YP group was (11.9±0.61)%. Compared with the control group, the apoptosis rate in the apatinib group was increased(P<0.05), while it was decreased in the 740YP group(P<0.05). When apatinib and 740YP were used in combination, the apoptosis rate was higher than that in the 740YP group(P<0.05). Compared with the control group, the expression of p-PI3K and p-Akt protein in the apatinib group was down-regulated(P<0.05), while they were up-regulated in the 740YP group (P<0.05). When apatinib and 740YP was used in combination, the expression of p-PI3K and p-Akt was down-regulated than that in the 740YP group(P<0.05). CONCLUSION Apatinib can induce apoptosis of nasopharyngeal carcinoma CNE-2Z cells by inhibiting the PI3K/Akt signal transduction pathway, thereby achieving the purpose of inhibiting its proliferation.