ABSTRACT
Objective:To evaluate the effectiveness and safety of concurrent chemoradiotherapy combined with nimotuzumab in the treatment of patients with inoperable esophageal squamous cell carcinoma (ESCC).Methods:A retrospective analysis was conducted on the clinical data of 503 patients with inoperable ESCC who underwent concurrent chemoradiotherapy in the Department of Radiation Oncology, Changzhou No. 2 People′s Hospital Affiliated to Nanjing Medical University and Department of Radiation Oncology, Affiliated Hospital of Jiangnan University from 2014 to 2020. Among these patients, 69 received concurrent chemoradiotherapy combined with nimotuzumab (the combined therapy group) and 434 received concurrent chemoradiotherapy alone (the concurrent chemoradiotherapy group). Patients of both groups were matched at a ratio of 1∶2 using the propensity score matching (PSM) method. As a result, 168 patients were determined for clinical analysis, including 61 in the combined therapy group and 107 in the concurrent chemoradiotherapy group. The short-term efficacy and adverse reactions of both groups were compared. The overall survival (OS) curves and progression-free survival (PFS) curves were plotted using the Kaplan-Meier method for the Log-rank test.Results:The two groups showed no statistical difference ( P > 0.05) in clinical baseline characteristics after the PSM. The objective response rate (ORR) of the combined therapy group was significantly higher than that of the concurrent chemoradiotherapy group with statistically significant differences (85.2% vs. 71.0%, χ2 = 4.33, P = 0.037). There was no statistical difference (98.4% vs. 91.6%, P > 0.05) in the disease control rate (DCR) between the two groups. The combined therapy group had median PFS of 28.07 months and 1-, 3-, and 5-year PFS ratios of 78.2%, 37.5% and 29.1%, respectively. The concurrent chemoradiotherapy group had mPFS of 19.54 months and 1-, 3-, and 5-year PFS ratios of 72.9%, 28.3% and 21.3%, respectively. Both groups showed statistically significant differences in PFS ( χ2 = 4.49, P = 0.034). The combined group had median OS of 34.93 months and 1-, 3-, and 5-year OS ratios of 88.5%, 46.8% and 37.4%, respectively. The concurrent chemoradiotherapy group had mOS of 24.30 months and 1-, 3-, and 5-year OS ratios of 81.3%, 35.2% and 28.0%, respectively. Both groups showed statistically significant differences in OS (χ 2= 5.11, P = 0.024), but did not show statistical differences ( P > 0.05) in the severity degree of each adverse effect during the treatment. Conclusions:Concurrent chemoradiotherapy combined with nimotuzumab can improve the ORR and prolong the PFS and OS of patients with inoperable ESCC compared with concurrent chemoradiotherapy alone. Furthermore, combining with nimotuzumab does not increase adverse effects and can be tolerated by patients with high safety.
ABSTRACT
Objective:To study the effects of poly adenosine diphosphate ribose polymerase (PARP) inhibitors niraparib and pamiparib on the radiosensitivity of breast cancer cell lines MCF-7 and MDA-MB-436, and to explore its mechanism.Methods:MCF-7 and MDA-MB-436 cells were divided into control group, niraparib group, pamiparib group, radiation group, combination group treated with niraparib and radiation, and combination group treated with pamiparib and radiation, respectively. The effects of drugs on cell proliferation and radiosensitivity were measured by CCK-8 assay and colony formation assay, respectively. The effect of drugs combined with radiation on cell cycle and apoptosis were detected by flow cytometry. Immunofluorescence method was used to detect the changes of γ-H2AX focal number of cells. The expressions of FANCG, Bax and Bcl-2 mRNA and protein were detected by qPCR and Western blot, respectively.Results:Both niraparib and pamiparib inhibited the proliferation of breast cancer cells MCF-7 and MDA-MB-436 in a time-dose dependent manner. With the increase of irradiation dose, D0, Dq, SF2 value of MCF-7 and MDA-MB-436 cells decreased, and SER D0 and SER Dq value increased. Compared with control group, the percentages of cells in G 2/M phase were increased ( tMCF-7=41.66, 44.08, P<0.05; t436=24.69, 18.91, P<0.05), the percentage of cells in G 0/G 1 phase were decreased ( tMCF-7=8.67, 29.61, P<0.05; t436=26.39, 29.12, P<0.05), and the cell apoptosis rate was significantly increased ( tMCF-7=11.17, 11.71, P<0.05; t436=42.68, 15.89, P<0.05) in the combination group. Compared with control group, the number of γ-H2AX foci of MCF-7 cells in the radiation group and combination group treated with niraparib and radiation increased significantly at 2 h after irradiation ( t=8.89, 21.72, P<0.05). At 24 h after irradiation, the number of γ-H2AX foci basically returned to normal level in the radiation group but remained at a higher level in the combination group ( t=8.82, P<0.05). Compared with control group, the expressions of FANCG and Bcl-2 mRNA decreased ( tFANCG=14.07, P<0.05; tBcl-2=29.21, P<0.05), the expression of Bax mRNA increased ( t=8.90, P<0.05), and the expression of FANCG and Bcl-2 proteins decreased ( tFANCG=7.09, P<0.05; tBcl-2=10.24, P<0.05), while the expression of Bax protein increased ( t=2.90, P<0.05) in the combination group. Conclusions:PARP inhibitors niraparib and pamiparib can increase the radiosensitivity of breast cancer MCF-7 and MDA-MB-436 cells probably through down-regulating the expression of FANCG in FA-BRCA pathway, up-regulating apoptosis-related genes and inhibiting DNA damage repair.