Microenviroment hypoxia is one of the common phenomenon in cancer,studies have indiacat-ed that hypoxia induces genetic instability via activating many DNA danlage-repair signal pathways,which asso-ciates with tumor invasion and resistance and chemi-radiotherapy resistivity.Here,we overview three main DNA damage-repair pathways:mismatch repair,homologous recombination and non-homologous end joining,and how hypoxia influences their mechanisms.

Objective: To study the effect of Kangai injection combined with GP chemotherapy in the treatment of patients with advanced non-small cell lung cancer(NSCLC) and its influence on quality of life (QOL). Methods: Eighty-five patients with advanced NSCLC were selected, and they were divided into control group(42 cases) and observation group (43 cases) according to the digital table.All patients were under the control of basic diseases and routine care.The control group was treated with GP regimen: gemcitabine combined with cisplatin, 21d as a course of treatment, continuous treatment for 4 courses.The observation group was treated with Kangai injection on the basis of the control group, and synchronized with chemotherapy.The immune function, QOL, curative effect and adverse reactions were compared between the two groups before and after treatment. Results: After treatment, the CD₃⁺ , CD₄⁺ , NK and CD₄⁺ /CD₈⁺ of the control group decreased, the CD₈⁺ increased, and the CD₃⁺ , CD₄⁺ , NK and CD₄⁺ /CD₈⁺ of the observation group increased, the CD₈⁺ decreased, the differences were statistically significant(t=6.704, 7.340, 11.080, 13.832, 5.033, all P<0.05). After treatment, the QOL scores of the observation group were higher than those of the control group(t=4.100, 6.698, 8.217, 4.146, 5.790, all P<0.05). The effective rate of the control group was 28.57%, which of the observation group was 41.86%, there was no statistically significant difference(χ²=1.643, P=0.200). The clinical control rate of the control group was 66.67%, which was lower than 86.05% of the observation group, the difference was statistically significant(χ²=4.435, P<0.05). The main side effects were myelosuppression and gastrointestinal reactions, and the incidence rates of WBC, thrombocytopenia and nausea and vomiting in the control group were higher than those in the observation group, the differences were statistically significant(χ²=8.880, 4.170, 0.553, 5.409, all P<0.05). Conclusion Kangai injection combined with GP chemotherapy in the treatment of patients with advanced NSCLC can improve the clinical control rate, QOL and immune function of patients, reduce the toxic and side effects, and it is worthy of promotion.