Abstract:Objective To explore the inhibitory effects of the anti-angiogenic drug apatinib and the commonly used chemotherapy drug adriamycin on the peripheral T-cell lymphoma (PTCL) cell line Hut78 and the related molecular mechanisms, in order to provide relevant experimental basis for the development of new treatment methods for PTCL.Methods Hut78 cells were divided into several groups with drug treatment of different concentrations: apatinib single agent (10, 20, 40, 60 μmol·L-1); adriamycin single agent (1, 2, 4 μmol·L-1); apatinib + adriamycin [(40+1) μmol·L-1, (40+2) μmol·L-1, (60+1) μmol·L-1, (60+2) μmol·L-1]. After treatment for 72 h, CCK-8 method was used to detect the inhibitory effects of drugs on the cell proliferation. Flow cytometry was used to detect the effects of drugs on the apoptosis of Hut78 cells in different concentrations treatment groups {[apatinib single agent (40 μmol·L-1), adriamycin single agent (1, 2 μmol·L-1), apatinib + adriamycin [(40+1) μmol·L-1, (40+2) μmol·L-1]} after 24 h, as well as the effects on the cell cycle of Hut78 cells in groups with different concentrations of apatinib (10, 20, 40 μmol·L-1) after 24 h. Western blotting was used to detect the expressions of PI3K/Akt signal pathway-related proteins (PI3K, p-PI3K, Akt and p-Akt) and apoptosis-related proteins (Bcl-2, Casepase-3 and Bax) in Hut78 cells in groups with different concentrations of drugs {[apatinib single agent (40 μmol·L-1), adriamycin single agent (1, 2 μmol·L-1), apatinib + adriamycin [(40+1) μmol·L-1, (40+2) μmol·L-1]} after 24 h.Results After treated with different concentrations (10, 20, 40, 60 μmol·L-1) of apatinib for 72 h, the inhibition rates of Hut78 cells were (13.42±2.19)%, (19.52±4.16)%, (31.49±3.16)%, (52.88±3.37)%, respectively. The IC50 value at 72 h was (59.34±0.31) μmol·L-1, and the differences were statistically significant between each treatment group and the control group (χ2=10.116, P=0.018). After treated with different concentrations (1, 2, 4 μmol·L-1) of adriamycin for 72 h, the inhibition rates of Hut78 cells were (15.82±3.23)%, (31.70±4.79)%, (42.34±5.23)%, respectively. And the IC50 value at 72 h was (5.52±0.18) μmol·L-1, and the differences were statistically significant between each treatment group and the control group (χ2=10.532, P=0.015). After treated with apatinib + adriamycin [(40+1) μmol·L-1, (40+2) μmol·L-1, (60+1) μmol·L-1, (60+2) μmol·L-1] for 72 h, the inhibition rates of Hut78 cells were (51.70±2.09)%, (56.62±4.83)%, (61.35±1.79)%, (65.13±3.88)%, respectively. The combination index (CI) value of the two drugs was < 1, suggesting a synergistic effect of the two drugs. Moreover, the apoptosis rate of Hut78 cells in groups of apatinib single agent (40 μmol·L-1) and adriamycin single agent (1, 2 μmol·L-1) after 24 h was respectively (15.65±0.75)%, (13.85±2.15)%, (23.60±1.30)%; while that was respectively (27.00±1.90)%, (33.20±2.30)% in the apatinib + adriamycin groups [(40+1) μmol·L-1, (40+2) μmol·L-1]. The differences between each treatment group and the control group [(6.10±0.90)%] was statistically significant (χ2=16.251, P=0.006). In addition, after treated with different concentrations of apatinib (10, 20, 40 μmol·L-1) for 24 h, the ratio of G0/G1 phase cells gradually increased [respectively (49.27±0.45)%, (50.34±1.24)%, (59.16±1.23)%], while the proportion of S phase cells gradually decreased [respectively (42.81±2.22)%, (39.19±2.71)%, (34.08±1.01)%]. The differences were statistically significant between each drug treatment group and the blank control group [G0/G1 phase ratio (39.26±0.65)%, S phase ratio (49.40±2.52)%] (P<0.05). Besides, after treatment with apatinib single agent (40 μmol·L-1), adriamycin single agent (1, 2 μmol·L-1), apatinib + adriamycin [(40+1) μmol·L-1, (40+2) μmol·L-1] for 24 h, the expression levels of PI3K/Akt signaling pathway-related proteins (PI3K, p-PI3K, p-Akt) and anti-apoptotic protein (Bcl-2) showed a downward trend, while the expression levels of the apoptotic proteins (Casepase-3 and Bax) showed an upward trend, and the expression level of Akt protein did not show a significant change. The protein expression levels of p-PI3K/PI3K, p-Akt/Akt, Bcl-2, Casepase-3, and Bax in each drug treatment group were statistically different from those in the control group (P<0.05).Conclusion Apatinib can inhibit the proliferation of PTCL cells, induce their apoptosis, and have a cell cycle arrest effect. Apatinib may inhibit the activation of PI3K/Akt signaling pathway and play a role in killing PTCL cells. Apatinib combined with adriamycin can exert a synergistic inhibitory effect on peripheral T-cell lymphoma cells.