Waniczek Dariusz, Śnietura Mirosław, Młynarczyk-Liszka Joanna, Pigłowski Wojciech, Kopeć Agnieszka, Lange Dariusz, Rudzki Marek, Arendt Jerzy
Department of General and Gastrointestinal Surgery, Bytom, Medical University of Silesia, Katowice, Poland.
Pol J Pathol. 2013 Apr;64(1):15-20. doi: 10.5114/pjp.2013.34598.
The aim of the study was to determine expression of the PTEN suppressor gene in colorectal adenocarcinoma and its precancerous lesions (adenomatous polyps) in correlation with common clinical and histopathological features. Forty-four patients with adenomatous polyps and 32 with primary adenocarcinoma of the colon or rectum were enrolled in the study. They underwent endoscopic removal of polyps or major surgery and postoperative adjuvant chemo- and radiotherapy depending on staging of the disease. No patient had received chemotherapy and/or radiotherapy before the surgery. PTEN expression was evaluated using immunohistochemical staining on paraffin-embedded specimens and compared to clinicopathological features of tumors. In colorectal cancers, PTEN expression was found to be significantly lower than in normal intestinal mucosa and adenomatous polyps. That was associated with complete loss of PTEN expression observed more frequently in colorectal cancer, contrary to reduction of PTEN expression occurring mostly in polyps. A correlation between polyp diameter and loss of PTEN was demonstrated as well as between tumor size and TNM advanced stage and PTEN expression. The obtained results suggest that the PTEN/PI3K/Akt pathway may play an important role in early stages of sporadic colorectal carcinogenesis and reduced PTEN expression in late oncogenesis is associated with some adverse clinical and pathological features.
本研究的目的是确定PTEN抑癌基因在结直肠癌及其癌前病变（腺瘤性息肉）中的表达，并将其与常见的临床和组织病理学特征相关联。44例患有腺瘤性息肉的患者和32例患有结肠或直肠癌原发性腺癌的患者纳入了本研究。他们接受了息肉的内镜切除或大手术，并根据疾病分期进行术后辅助化疗和放疗。没有患者在手术前接受过化疗和/或放疗。使用免疫组织化学染色对石蜡包埋标本评估PTEN表达，并将其与肿瘤的临床病理特征进行比较。在结直肠癌中，发现PTEN表达明显低于正常肠黏膜和腺瘤性息肉。这与在结直肠癌中更频繁观察到的PTEN表达完全丧失有关，相反，PTEN表达的降低主要发生在息肉中。证实了息肉直径与PTEN缺失之间以及肿瘤大小与TNM晚期和PTEN表达之间存在相关性。所获得的结果表明，PTEN/PI3K/Akt途径可能在散发性结直肠癌发生的早期阶段起重要作用，而在肿瘤发生后期PTEN表达降低与一些不良的临床和病理特征相关。
