Experimental Study On Antitumor Effect Of Apatinib Combined With Chemoradiotherapy On Cervical Cancer

Objective:Cervical cancer is a common gynecological malignancy.In addition to surgery,radiotherapy is an important treatment.Clinically,the vast majority of cervical cancer patients have been diagnosed locally at the time of local advanced radiation therapy combined with chemotherapy is an important treatment model.Cisplatin?DDP?is the most commonly used concurrent chemoradiotherapy drug.Apatinib?APA?is a new anti-angiogenic drug,highly selective for vascular endothelial growth factor?VEGF?receptor?VEGFR?,and radiotherapy.Joint therapy for tumors is less studied.Lack of research reports on the use of cervical cancer.The main purpose of this study was to investigate the anti-cancer effects of cisplatin-based concurrent chemoradiation with or without apatinib in cervical cancer.Methods:A HeLa tumor-bearing mouse model was established.60 nude mice bearing tumors were randomly divided into 5 groups with 12 mice in each group:?1?Control group:0.9%NS 0.1 ml/d ip d1-7;?2?Radiotherapy group?RT?:RT 8Gy d1;?3?Cisplatin+radiotherapy group?DDP+RT?:DDP d1+RT8Gy d1;?4?Apatinib+radiotherapy group?APA+RT?:APA 200mg/kg/d Ip d1-7+RT 8Gy d7;?5?Apatinib+cisplatin+radiotherapy group?APA+DDP+RT?:APA 200 mg/kg/d ip d1-7+DDP 5 mg/kg/d ig d7+RT 8Gy D7.On the second day after the treatment,6 nude mice were randomly selected for ¹⁸F-FDG PET-CT examination in each group to obtain PET-CT images and corresponding SUV values.Subsequently,each group of nude mice that had undergone ¹⁸F-FDG PET-CT examination was sacrificed and the tumor mass was removed.The tumor tissues of each group were embedded in paraffin embedded sections and immunohistochemistry was used to detect the expression of VEGFR-2,CD31,?-H2AX,and Ki-67.Tunel method to detect apoptosis.The remaining groups of untreated nude mice were observed for changes in survival and tumor volume,and tumor growth curves and survival curves were plotted.Results:Experimental results showed that after 25 days of tumor volume observation,the final tumor volume of APA+DDP+RT group?910.46±105.47?was significantly lower than that of APA+RT group?1156.38±110.75?and DDP+RT group?1234.51±140.64?.The difference was statistically significant?P<0.05?.The tumor inhibition rate of APA+DDP+RT group?66.99%?was 10%higher than that of APA+RT group?57.00%?and 14.41%higher than that of DDP+RT group?52.58%?.The difference was statistically significant?P<0.05?.The tumor inhibition rate in the APA+DDP+RT group?66.99%?was nearly 2-fold higher than that in the RT group?34.83%??P<0.05?.The median survival time in the APA+DDP+RT group?86 days?was 14 days longer than that in the DDP+RT group?72 days?,and was 3 days longer than that in the APA+RT group?83 days?.The difference was statistically significant?P<0.05?.When combined APA+RT group?83 days?,APA+DDP+RT group?86 days?with Control group?42 days?,RT group?61 days?,the difference was statistically significant?P<0.05?.The results of immunohistochemistry?CD31?showed that the number of positive blood vessels in the DDP+RT group?3.57±0.65?was more than three times higher than that in the APA+DDP+RT group?1.04±0.32?,and that in the APA+RT group was?2.16±0.42?.In the APA+DDP+RT group?1.04±0.32?,the difference was statistically significant?P<0.05?.The number of positive blood vessels in the RT group?5.37±0.86?was more than twice as high as that in the APA+RT group?2.16±0.42?.The difference was statistically significant?P<0.05?.The Microvessel Density?MVD?was highest in the Control group,and the number of positive blood vessels was as high as 7.64±0.95.Compared with other groups,the difference was statistically significant?P<0.05?.Immunohistochemical detection of VEGFR-2 suggested that after APA combined with radiotherapy,the rate of VEGFR-2 positive cells in APA+RT group?13.73±1.92?was significantly lower than that in RT group?78.23±5.90?and DDP+RT group?65.38±4.45?,the difference was statistically significant?P<0.05?.After the addition of DDP,the positive rate of VEGFR-2 expression in APA+DDP+RT group?7.39±1.06?decreased moresignificantly?P<0.05?.Theresultsof?-H2AX immunohistochemistry showed that the rate of?-H2AX positive cells in the DDP+RT group?41.82±4.29?was nearly 2 times higher than that in the RT group?21.45±3.06?,and the difference was statistically significant?P<0.05?.After combined with APA,the rate of?-H2AX positive cells in APA+DDP+RT group?51.15±5.40?was 9.33 higher than that in DDP+RT group?41.82±4.29?and 15.45%higher than in APA+RT group?35.70±4.67?.The difference was statistically significant?P<0.05?.The rate of?-H2AX positive cells in the APA+RT group?35.70±4.67?was similar to that in the DDP+RT group?41.82±4.29?,and the difference was not statistically significant?P>0.05?.The control group?5.46±1.01?was the lowest,significantly lower than the other groups,the difference was statistically significant?P<0.05?.Ki-67 immunohistoc-hemistry results showed that after APA combined with radiotherapy,the positive expression rate of Ki-67 in the APA+RT group?14.40±2.72?was nearly5-fold lower than that in the RT group?66.78±5.01?,3-fold lower than that in the DDP+RT group?42.64±3.23?,and the difference was statistically significant?P<0.05?.After DDP was added,the positive expression rate of Ki-67 in the APA+DDP+RT group?7.20±0.93?decreased exponentially and was 1/2 of the APA+RT group?14.40±2.72?,1/6 of the DDP+RT group?42.64±3.23?,the difference was statistically significant?P<0.05?.The small animal ¹⁸F-FDG PET-CT suggested that the SUV values in the APA+RT group?1.52±0.0.08?and DDP+RT group?1.91±0.19?were lower than those in the RT group?2.61±0.23?,and the difference was statistically significant?P<0.05?.The SUV value of APA+DDP+RT group?0.82±0.06?was significantly lower than that of APA+RT group?1.52±0.08?and DDP+RT group?1.91±0.19?,and the difference was statistically significant?P<0.05?.The control group?3.21±0.34?had the highest SUV value,and there was a statistically significant difference?P<0.05?compared with the other groups.Conclusion:1.Apatinib combined with cisplatin can significantly enhance the effect of radiation on cervical cancer,and its mechanism may be related to anti-angiogenesis,DNA double-strand breaks,inhibition of proliferation,and promotion of apoptosis;2.Apatinib combined with cisplatin-based concurrent chemo-radiotherapy can significantly inhibit the growth of cervical cancer xenografts and prolong the survival of nude mice.