Objective: To explore the anti-tumor effects of oxaliplatin (OXA) combined with PD-1 antibody on colon cancer. Methods: Flow cytometry was used to detect the expression of PD-L1 in colon cancer cell lines HCT-116 and HT-29. Co-culture method was used to detect the secretion of cytokines and the changes of CD4/CD8 subsets in T-cells that co-cultured with HCT-116 cells, which were pretreated with OXAin combination with/without PD-1 antibody; The CT26 transplanted tumor model of colon cancer in BALB/c mice was established and treated with the combination of OXA and PD-1 to evaluate their anti-tumor efficacy. Meanwhile, CD8 antibody was used to scavenge CD8+ T cells in mice, and to evaluate the role of CD8+ T cells in the anti-tumor effect of OXA in vivo. Results: OXAcould significantly increase the expression of PD-L1 on the surface of colon cancer cells. Compared with pure T-cells, the T cells co-cultured with colon cancer HCT-116 cells that pre-treated by OXA, exhibited significantly reduced IL-2, IFN-γ and TNF levels (all P<0.05) in its culture supernatant and decreased ratio of CD4+memory T cell / CD8+TEMER (P<0.05), whereas there was increased cell proportion of the CD4+ (P>0.05) and CD8+ (P<0.05) naïve T cells. After co-treated with PD-1 antibody, compared with the single treatment of OXA, IFN-γ and IL-10 content (P<0.05) in culture supernatant and the subsets of CD8+ TCM and TEMRA ratio (P>0.05) were increased. In vivo experiments showed that OXAcombined with PD-1 antibody could enhance its anti-tumor activity, the tumor suppression rates were 25.6% (OXA) and 29.1% (αPD-1), respectively, however, the rate of tumor inhibition was increased to 58.2% when combined (P<0.05, compared to OXA or αPD-1 group). After scavenging CD8+T cells in mice, the antitumor activity of OXA dropped from 68.4% to 46.2% (P<0.05). Conclusion: OXA combined with PD-1 antibody had synergistic anti-tumor effect, and CD8+ T cells played an important role in the antitumor activity of OXA.

[摘 要] 目的：探索预后营养指数（PNI）在接受诱导化疗联合免疫（化免）序贯放疗的局部晚期食管鳞状细胞癌（ESCC）中的疗效预测价值及预后影响。方法: 回顾性分析浙江省肿瘤医院2019年5月至2023年8月期间收治的126例行诱导化免序贯放疗的局部晚期ESCC患者的临床资料。绘制受试者工作特征曲线（ROC曲线），确定患者诱导化免前1周内、放疗前1周内、放疗开始后4 ± 1周的PNI最佳临界值并对患者进行分组。采用Kaplan-Meier法绘制生存曲线，并用Log-Rank法比较组间患者的总生存期（OS）及无进展生存期（PFS），采用Cox回归分析探讨诱导化免序贯放疗的局部晚期ESCC患者的预后影响因素。结果: 共纳入126例局部晚期ESCC患者，男性118例，女性8例，中位年龄65岁（44~78岁）。运用ROC曲线确认的患者诱导化免前、放疗前和放疗中PNI最佳临界值为46.2、48.3和37.9。放疗前PNI ≥ 48.3组中位OS、PFS分别为47.3、28.2个月，放疗前PNI < 48.3组中位OS、PFS分别为18.7、15.2个月（P < 0.01，P < 0.05）。放疗中PNI ≥ 37.9组中位OS未达到，中位PFS为25.7个月，放疗中PNI < 37.9组中位OS、PFS分别为17.0、12.5个月（P < 0.01，P < 0.05）。诱导化免后PNI升高组中位OS未达到，中位PFS为28.4个月；PNI降低组中位OS、PFS分别为20.4、16.0个月（P < 0.01，P < 0.05）。多因素分析显示，放疗中PNI[HR = 2.292，95% CI（1.264,4.159），P < 0.05]、诱导化免后PNI变化[HR = 2.120, 95% CI（1.007, 4.463），P < 0.05]为影响OS因素。结论: 放疗中PNI、诱导化免后PNI变化与患者治疗疗效及预后有一定相关性，可作为预测ESCC化免序贯放疗获益的重要指标。