5-FU化疗胃癌患者预后相关生物标志物的筛选及临床价值分析

Screening of prognostic biomarkers and analysis of their clinical value in gastric cancer patients receiving 5-FU-based chemotherapy

摘要

目的 筛选与5-氟尿嘧啶（5-FU）治疗胃癌患者预后相关的预测因子，评估胸苷酸合成酶（TS）、二氢嘧啶脱氢酶（DPD）、胸苷磷酸化酶（TP）及Polo样激酶1相互作用检查点解旋酶（PICH）的临床预测价值，为胃癌患者个体化治疗及预后评估提供依据。方法 回顾性纳入120例接受根治术后5-FU为基础辅助化疗的胃癌患者。术后辅助化疗主要包括FOLFOX、SOX及5-FU/LV 方案，通常接受6~8 个周期治疗，约86.7% 的患者完成全部计划周期，其余患者因不良反应出现剂量调整或周期延迟。采用免疫组织化学检测PICH、DPD、TP 及TS 表达，所有病理切片由2 名具有高级职称的病理医师在未知临床资料的情况下独立判读，如存在评分分歧，则由第3 名病理医师复核并裁决，Kappa 值为0.82。主要终点为总生存期（OS）。采用Kaplan-Meier法绘制生存曲线并进行log-rank 检验，采用Cox 比例风险回归模型分析预后相关因素，并以受试者操作特征（ROC）曲线进行预后判别的探索性分析。结果 全队列中位随访时间为 36 个月，共观察到死亡事件63例（52.5%），删失57例（47.5%）。单因素Cox分析显示，Lauren分型中弥漫型相对于肠型与较差OS显著相关（HR=3.26，95%CI：1.97~5.39，P<0.001），混合型相对于肠型差异无统计学意义（HR=0.77，95%CI：0.49~1.21，P=0.251）；PICH 低表达与更好OS 显著相关（HR=0.30，95%CI：0.19~0.47，P<0.001）。多因素 Cox 分析显示，PICH 低表达仍是 OS 的独立保护因素（HR=0.38，95%CI：0.22~0.64，P<0.001），Lauren 弥漫型相对于肠型呈风险升高趋势（HR=1.86，95%CI：0.97~3.58，P=0.061），混合型差异无统计学意义（HR=1.13，95%CI：0.67~ 1.90，P=0.655）。ROC 曲线分析提示PICH 的预后判别能力优于DPD、TP 及TS。结论 PICH低表达与接受5-FU为基础辅助化疗的胃癌患者较好OS独立相关，可作为潜在预后生物标志物，Lauren分型在本研究中的方向和强度未显示稳定独立保护效应，仍需在更大样本中进一步验证。

Abstract

Objective To identify prognostic factors in gastric cancer patients treated with 5-fluorouracil (5-FU) -based chemotherapy and to evaluate the clinical predictive value of thymidylate synthase (TS), dihydro-pyrimidine dehydrogenase (DPD), thymidine phosphorylase (TP), and Polo-like kinase 1-interacting checkpoint helicase (PICH) as candidate biomarkers, thereby providing a basis for individualized treatment and prognostic assessment. Methods This retrospective study included 120 patients with gastric cancer who underwent radical surgery followed by 5-FU-based adjuvant chemotherapy. The major regimens were FOLFOX, SOX, and 5-FU/LV, usually administered for 6-8 cycles. Approximately 86.7% of patients completed all planned cycles, while the remaining patients required dose adjustments or experienced cycle delays due to adverse reactions. Protein expression of PICH, DPD, TP, and TS was assessed by immunohistochemistry. All pathological slides were independently reviewed by two senior pathologists in a blinded manner. Any discrepancies were reviewed and adjudicated by a third pathologist. The Kappa value was 0.82. Overall survival (OS) was the primary endpoint. Kaplan-Meier survival curves were constructed and compared using the log-rank test, and Cox proportional hazards models were used to analyze prognostic factors. Receiver operator characteristic (ROC) curve analysis was further conducted as an exploratory assessment of prognostic discrimination. Results The median follow-up time for the entire cohort was 36 months, during which 63 deaths (52.5%) were observed, and 57 patients were censored (47.5%). Univariate Cox analysis showed that, within the Lauren classification, the diffuse type was significantly associated with poorer OS compared with the intestinal type (HR=3.26, 95%CI:1.97-5.39, P<0.001), whereas the mixed type showed no statistically significant difference (HR=0.77, 95%CI: 0.49-1.21, P=0.251). Low PICH expression was significantly associated with improved OS (HR=0.30, 95%CI: 0.19-0.47, P<0.001). Multivariable Cox analysis further indicated that low PICH expression remained an independent protective factor for OS (HR=0.38, 95%CI: 0.22-0.64, P<0.001). The diffuse type in the Lauren classification showed a borderline adverse trend compared with the intestinal type (HR=1.86, 95%CI: 0.97-3.58, P=0.061), while the mixed type showed no statistically significant difference (HR=1.13, 95%CI: 0.67-1.90, P=0.655). ROC curve analysis suggested that PICH had better prognostic discrimination than DPD, TP, and TS. Conclusion Low PICH expression is independently associated with favorable OS in gastric cancer patients receiving 5-FU-based adjuvant chemotherapy and may serve as a potential prognostic biomarker. The Lauren classification does not demonstrate a stable independent protective effect in terms of direction and magnitude in this study and requires further validation in larger cohorts.

关键词

胃癌 / 5-氟尿嘧啶 / Polo样激酶1相互作用检查点解旋酶 / 二氢嘧啶脱氢酶 / 胸苷磷酸化酶 / 胸苷酸合成酶

Key words

Gastric cancer / 5-fluorouracil / Polo-like kinase 1-interacting checkpoint helicase / Dihydropyrimidine dehydrogenase / Thymidine phosphorylase / Thymidylate synthase

参考文献

[1] SMYTH E C, NILSSON M, GRABSCH H I, et al. Gastric cancer[J]. The Lancet, 2020, 396(10251): 635-648.

[2] AJANI J A, D'AMICO T A, BENTREM D J, et al. Gastric cancer, version 2.2022, NCCN clinical practice guidelines in oncology[J]. Journal of the National Comprehensive Cancer Network, 2022, 20(2): 167-192.

[3] JOSHI S S, BADGWELL B D. Current treatment and recent progress in gastric cancer[J]. CA: A Cancer Journal for Clinicians, 2021, 71(3): 264-279.

[4] LONGLEY D B, HARKIN D P, JOHNSTON P G. 5- fluorouracil: Mechanisms of action and clinical strategies[J]. Nature Reviews Cancer, 2003, 3(5): 330-338.

[5] SEXTON R E, AL HALLAK M N, DIAB M, et al. Gastric cancer: A comprehensive review of current and future treatment strategies[J]. Cancer Metastasis Reviews, 2020, 39(4): 1179-1203.

[6] ZHANG X, SUN K, WANG L. DPD and TS expression as predictive biomarkers for fluoropyrimidine-based chemotherapy in gastric cancer[J]. BMC Cancer, 2021, 21: 1067.

[7] ICHIKAWA W. Prediction of clinical outcome of fluoropyrimidine-based chemotherapy for gastric cancer patients, with special reference to gene expression[J]. International Journal of Clinical Oncology, 2020, 25(3): 458-465.

[8] KIM H S, KIM J H, KIM J W. Clinical significance of thymidylate synthase and dihydropyrimidine dehydrogenase expression in gastric cancer treated with fluoropyrimidine- based chemotherapy[J]. Anticancer Research, 2021, 41(5): 2561-2570.

[9] YE H, SHI W, YANG J, et al. PICH activates Cyclin A 1 transcription to drive S-phase progression and chemoresistance in gastric cancer[J]. Cancer Research, 2023, 83(22): 3767-3782.

[10] BAUMANN C, KÖRNER R, HOFMANN K. PICH, a centromere-associated SNF2 family ATPase, is required for faithful chromosome segregation[J]. The EMBO Journal, 2007, 26(21): 4507-4519.

[11] ZHANG Y, LIU H, LI W. Overexpression of PICH predicts unfavorable prognosis and promotes proliferation in solid tumors[J]. Journal of Translational Medicine, 2021, 19: 412.

[12] SUN Q, ZHAO X, YANG L. Mitotic checkpoint helicase PICH is a potential therapeutic target in cancer[J]. Frontiers in Oncology, 2023, 13: 1189452.

[13] HARRELL F E JR. Regression modeling strategies: With applications to linear models, logistic regression, and survival analysis[M]. New York: Springer, 2015.

[14] HU Y, ZHENG M, ZHANG D. Identification of novel prognostic biomarkers in gastric cancer based on DNA damage repair-related genes[J]. Frontiers in Genetics, 2022, 13: 842561.

[15] WANG J, LI X, CHEN Y. PICH regulates DNA damage response and contributes to chemoresistance through checkpoint control[J]. Molecular Oncology, 2022, 16(8): 1856-1872.

[16] LEE J H, KIM S T, PARK S H. Thymidylate synthase expression and survival in gastric cancer patients treated with fluoropyrimidine-based chemotherapy[J]. Cancer Chemotherapy and Pharmacology, 2020, 85(2): 359-368.

[17] O'CONNOR M J. Targeting the DNA damage response in cancer[J]. Molecular Cell, 2015, 60(4): 547-560.

[18] LORD C J, ASHWORTH A. The DNA damage response and cancer therapy[J]. Nature, 2012, 481(7381): 287-294.

[19] PILIÉ P G, TANG C, MILLS G B. State-of-the-art strategies for targeting the DNA damage response in cancer[J]. Nature Reviews Clinical Oncology, 2019, 16(2): 81-104.

[20] WANG Z, LI Y, AHMAD A. Targeting DNA repair pathways in cancer therapy[J]. Cancer Letters, 2020, 470: 1-11.

[21] JACKSON S P, BARTEK J. The DNA-damage response in human biology and disease[J]. Nature, 2009, 461(7267): 1071-1078.

[22] CHAE Y K, ANKER J F, OH M S, et al. Mutations in DNA repair genes and response to chemotherapy in gastrointestinal cancers[J]. The Oncologist, 2020, 25(3): e453-e462.

[23] LI X, HEYER W D. Homologous recombination in DNA repair and DNA damage tolerance[J]. Cell Research, 2008, 18(1): 99-113.

[24] PEARL L H, SCHIERZ A C, WARD S E, et al. Therapeutic opportunities within the DNA damage response[J]. Nature Reviews Cancer, 2015, 15(3): 166-180.

[25] ZHANG H, CHEN Z H, SAVARESE T M. Codependent relationship between autophagy and DNA damage response in cancer[J]. Frontiers in Oncology, 2021, 11: 640009.

[26] ZHAO L, LI P, GONG Z. DNA damage repair and resistance to chemotherapy in cancer[J]. Frontiers in Cell and Developmental Biology, 2022, 10: 873687.

[27] VAN CUTSEM E, SAGAERT X, TOPAL B, et al. Gastric cancer[J]. The Lancet, 2016, 388(10060): 2654-2664.

[28] HEAGERTY P J, LUMLEY T, PEPE M S. Time-dependent ROC curves for censored survival data and a diagnostic marker[J]. Biometrics, 2000, 56(2): 337-344.

[29] STEYERBERG E W, VICKERS A J, COOK N R, et al. Assessing the performance of prediction models: A framework for traditional and novel measures[J]. Epidemiology, 2010, 21(1): 128-138.

基金资助

国家自然科学基金项目(82560480)