在各种癌症中，过度表达脱嘌呤/脱嘧啶内切酶1 (APE1) 已被证明与癌症进展、抗化疗和抗放射线治疗有关。本研究检测了APE1的表达及其与结直肠癌 (CRC) 患者肿瘤进展和预后的关系。我们调查了193名接受根治性手术的 CRC 患者，可提供福尔马林固定和石蜡包埋的组织块，并进行了长期特定于肿瘤的生存率分析。采用逆转录聚合酶链式反应、蛋白质印迹法和免疫组化法研究了 CRC 和淋巴结组织中 APE1 的表达。利用末端脱氧核苷酸转移酶介导的 dUTP 末端标记法、Ki-67 和 CD34 抗体的免疫组织化学染色测定了 CRC 细胞的凋亡、增殖和血管生成。与正常结直肠黏膜和非转移性淋巴结组织相比，APE1 在 CRC 和转移性淋巴结组织中被过度表达。APE1 的过度表达与晚期、淋巴血管侵犯、神经周围侵犯、更深的肿瘤侵袭、淋巴结转移、远处转移和差的生存率显著相关。多变量分析表明，APE1、神经周围侵犯和淋巴结转移是与总生存率相关的独立预后因素。APE1 阳性肿瘤的平均 Ki-67 标记指数值显著高于 APE1 阴性肿瘤。然而，APE1 的表达与凋亡指数或微血管密度之间没有显著关联。在 CRC 患者中，APE1 的过度表达与肿瘤进展和差的生存率显著相关。因此，APE1 可能是一种新的生物标志物，具有 CRC 的潜在预后因素。版权所有 © 2023 国际抗癌研究院 (George J. Delinasios 博士)，保留所有权利。

Over-expression of apurinic/apyrimidinic endonuclease 1 (APE1) has been demonstrated to be associated with cancer progression, chemo- and radioresistance in various cancers. This study examined the expression of APE1 and its relation to tumor progression and prognosis in patients with colorectal cancer (CRC).We investigated 193 patients with CRC who received curative surgery for whom formalin-fixed and paraffin-embedded blocks were available, and long-term tumor-specific survival rate analysis was possible. The expression of APE1 was investigated by reverse transcription-polymerase chain reaction, western blotting, and immunohistochemistry in CRC and lymph node tissues. The apoptosis, proliferation, and angiogenesis of CRC cells were determined using terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling assay, and immunohistochemical staining for Ki-67 and CD34 antibodies.APE1 was over-expressed in CRC and metastatic lymph node tissues compared with normal colorectal mucosa and non-metastatic lymph node tissues. Over-expression of APE1 was significantly associated with advanced stage, lymphovascular invasion, perineural invasion, deeper tumor invasion, lymph node metastasis, distant metastasis, and poor survival. Multivariate analysis demonstrated that APE1, perineural invasion, and lymph node metastasis were the independent prognostic factors associated with overall survival. The mean Ki-67 labeling index value of APE1-positive tumors was significantly higher than that of APE1-negative tumors. However, there was no significant association between APE1 expression and the apoptotic index or microvessel density.Over-expression of APE1 is significantly associated with tumor progression and poor survival in patients with CRC. Therefore, APE1 may be a novel biomarker and present a potential prognostic factor for CRC.Copyright © 2023, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.