Chen Sheng, Dong Quan-Jin, Wan Zi-Ang, Gao Shan, Tu Shi-Liang, Chai Rui
General Surgery, Cancer Center, Department of Colorectal Surgery, Zhejiang Provincial People's Hospital, Affiliated People's Hospital of Hangzhou Medical College, Hangzhou City, Zhejiang Province 310014, China.
Gastroenterol Res Pract. 2022 May 16;2022:6972331. doi: 10.1155/2022/6972331. eCollection 2022.
BHLHE41 has been shown to be a marker of tumorigenesis. Colon cancer (CC) is a common malignant tumor of colonic mucosa. This study mainly explored the mechanism of BHLHE41 in alleviating malignant behavior of hypoxia-induced CC cells.
The levels of BHLHE41 in CC and normal cell lines were tested by Western blot and qRT-PCR. After, CC cells were subjected to hypoxia treatment and BHLHE41 overexpression transfection, and the BHLHE41 expression, the effect of BHLHE41 on CC cell viability, apoptosis, migration, and invasion and cell cycle were tested by qRT-PCR and relevant cell functional experiments. HIF-1 and epithelial-mesenchymal transition- (EMT-) related proteins were tested by Western blot. Moreover, CC tumor-bearing model was established in nude mice, and the effect of BHLHE41 on the tumor was evaluated by measuring the tumor volume and weight. Then, the expressions of BHLHE41 and EMT-related proteins were detected by immunohistochemistry and Western blot.
Western blot and qRT-PCR showed that BHLHE41 was lowly expressed in CC cells. BHLHE41 overexpression could inhibit the hypoxia-induced CC cell viability, migration, and invasion, induce apoptosis, and alter cell cycle. Besides, BHLHE41 overexpression could enhance the levels of E-cadherin but reduce the levels of HIF-1, N-cadherin, vimentin, and MMP9 in hypoxia-induced CC cells. Moreover, BHLHE41 overexpression reduced tumor volume, weight, and EMT-related proteins levels in tumor tissues.
BHLHE41 overexpression could mitigate the malignant behavior of hypoxia-induced CC via modulating the HIF-1/EMT pathway.
BHLHE41已被证明是肿瘤发生的标志物。结肠癌（CC）是结肠黏膜常见的恶性肿瘤。本研究主要探讨BHLHE41减轻缺氧诱导的CC细胞恶性行为的机制。
通过蛋白质免疫印迹法（Western blot）和实时定量逆转录聚合酶链反应（qRT-PCR）检测CC和正常细胞系中BHLHE41的水平。之后，对CC细胞进行缺氧处理和BHLHE41过表达转染，并通过qRT-PCR和相关细胞功能实验检测BHLHE41的表达、BHLHE41对CC细胞活力、凋亡、迁移、侵袭及细胞周期的影响。通过蛋白质免疫印迹法检测缺氧诱导因子-1（HIF-1）和上皮-间质转化（EMT）相关蛋白。此外，在裸鼠中建立CC荷瘤模型，通过测量肿瘤体积和重量评估BHLHE41对肿瘤的影响。然后，通过免疫组织化学和蛋白质免疫印迹法检测BHLHE41和EMT相关蛋白的表达。
蛋白质免疫印迹法和qRT-PCR显示BHLHE41在CC细胞中低表达。BHLHE41过表达可抑制缺氧诱导的CC细胞活力、迁移和侵袭，诱导凋亡并改变细胞周期。此外，BHLHE41过表达可提高缺氧诱导的CC细胞中E-钙黏蛋白水平，但降低HIF-1、N-钙黏蛋白、波形蛋白和基质金属蛋白酶9（MMP9）的水平。而且，BHLHE41过表达可降低肿瘤组织的肿瘤体积、重量和EMT相关蛋白水平。
BHLHE41过表达可通过调节HIF-1/EMT途径减轻缺氧诱导的CC的恶性行为。
