Sukor Nur Fazilah, Yahaya Azyani, Sagap Ismail, Jamal Rahman, Johdi Nor Adzimah
UKM Medical Molecular Biology Institute (UMBI), National University Malaysia, Cheras, Malaysia.
Department of Pathology, Faculty of Medicine, National University Malaysia, Cheras, Malaysia.
Turk J Biol. 2022 Jul 14;46(5):361-374. doi: 10.55730/1300-0152.2623. eCollection 2022.
Colorectal cancer (CRC) is a malignant tumor arising from a human inner colon lining that may spread to other organs such as the liver and lungs. Per ARNT Sim domain containing 1 (PASD1) is a cancer-testis antigen expressed in cancers including CRC but not in normal tissues except for normal testes. This study aims to study PASD1 protein as a potential target for CRC immunotherapy. A total of 90 CRC and polyps tissue samples were investigated for PASD1 RNA and protein expression using a real-time polymerase chain reaction and immunohistochemical staining, respectively. Matched patients' peripheral blood mononuclear cells were pulsed with PASD1 peptides and measured for immunogenicity, cell cytotoxicity, and cytokine assays. The clinical data were collected and analyzed accordingly. Our results show that mRNA expression was highly expressed in CRC (46.0%) and polyps samples (33.3%). Both PASD1-1 and PASD1-2 proteins were expressed in 31.7% of CRC and 29.4% of polyps samples. Protein expression was weak to moderate positive in the cytoplasm and/or nucleus of the tissues. Immune responses towards CD4-specific PASD1 peptides were detected in 21.7% of CRC and 23.5% of polyps patients. The most immunogenic peptide was PASD1 (1) in CRC while PASD1 (3) in polyps. Cytotoxicity effects were detected up to 57.20% observed in CRC samples while IL-17A and IL-6 cytokines were highly expressed. The demographic data suggest that Chinese female patients more than 60 years old, diagnosed with late-stage rectosigmoid tumors may benefit from the PASD1 peptide immunotherapy approach. This is the first report describing CD4-positive T-helper response to the PASD1 positive CRC patients and its cytotoxicity.
结直肠癌（CRC）是一种起源于人体结肠内层的恶性肿瘤，可能会扩散到肝脏和肺等其他器官。含ARNT Sim结构域1（PASD1）是一种癌胚抗原，在包括CRC在内的多种癌症中表达，但除正常睾丸外，在正常组织中不表达。本研究旨在研究PASD1蛋白作为CRC免疫治疗的潜在靶点。分别使用实时聚合酶链反应和免疫组织化学染色，对总共90份CRC和息肉组织样本进行PASD1 RNA和蛋白表达研究。用PASD1肽刺激匹配患者的外周血单核细胞，并检测其免疫原性、细胞毒性和细胞因子分析。相应地收集并分析临床数据。我们的结果表明，mRNA表达在CRC（46.0%）和息肉样本（33.3%）中高表达。PASD1-1和PASD1-2蛋白在31.7%的CRC和29.4%的息肉样本中表达。蛋白表达在组织的细胞质和/或细胞核中呈弱阳性至中度阳性。在21.7%的CRC和23.5%的息肉患者中检测到对CD4特异性PASD1肽的免疫反应。CRC中最具免疫原性的肽是PASD1（1），而息肉中是PASD1（3）。在CRC样本中观察到高达57.20%的细胞毒性作用，同时IL-17A和IL-6细胞因子高表达。人口统计学数据表明，60岁以上、被诊断为晚期直肠乙状结肠肿瘤的中国女性患者可能从PASD1肽免疫治疗方法中获益。这是第一份描述CD4阳性T辅助细胞对PASD1阳性CRC患者的反应及其细胞毒性的报告。
