Roy Badal Chandra, Ahmed Ishfaq, Ramalingam Satish, Jala Venkatakrishna, Haribabu Bodduluri, Ramamoorthy Prabhu, Ashcraft John, Valentino Joseph, Anant Shrikant, Sampath Venkatesh, Umar Shahid
Departments of Surgery and Cancer Biology, University of Kansas Medical Center, Kansas City, KS, USA.
Department of Genetic Engineering, School of Bio-Engineering, SRM Institute of Science and Technology, Kattankulathur, Kanchipuram, Tamil Nadu, India.
Oncotarget. 2019 Mar 22;10(24):2340-2354. doi: 10.18632/oncotarget.26684.
Autophagy may play a critical role in colon cancer stem cells (CCSCs)-related cancer development. Here, we investigate whether accumulation of infection/injury-induced CCSCs due to impaired autophagy influences colon cancer development and progression. When mice were infected with (CR; 10CFUs), we discovered presence of autophagosomes with increases in Beclin-1, LC3B and p62 staining during crypt hyperplasia. mice when infected with CR or subjected to CR+AOM treatment, exhibited increased colon tumorigenesis with elevated levels of Ki-67, β-catenin, EZH2 and CCSC marker Dclk1, respectively. AOM/DSS treatment of mice phenocopied CR+AOM treatment as colonic tumors exhibited pronounced changes in Ki-67, EZH2 and Dclk1 accompanied by infiltration of F4/80+ macrophages, CD3+ lymphocytes and CD3/β-catenin co-localization. Intestinal and colonic tumors also stained positive for migrating CSC markers CD110 and CDCP1 wherein, colonic tumors additionally exhibited stromal positivity. In tumors from CR-infected, CR+AOM or AOM/DSS-treated mice and surgically-resected colon tumor/metastatic liver samples, significant accumulation of p62 and it's co-localization with LC3B and Dclk1 was evident. mice when infected with CR and mice, exhibited similar co-localization of p62 with LC3B and Dclk1 within the tumors. Studies in HCT116 and SW480 cells further confirmed p62/Dclk1 co-localization and Chloroquin/LPS-induced increases in Dclk1 promoter activity. Thus, co-localization of p62 with Dclk1 may hamper Dclk1's elimination to impact colon cancer development and progression.
自噬可能在结肠癌干细胞（CCSCs）相关的癌症发展中起关键作用。在此，我们研究由于自噬受损导致的感染/损伤诱导的CCSCs积累是否会影响结肠癌的发展和进展。当小鼠感染（CR；10CFUs）时，我们发现在隐窝增生期间存在自噬体，且Beclin-1、LC3B和p62染色增加。感染CR或接受CR+AOM处理的小鼠分别表现出结肠癌发生增加，同时Ki-67、β-连环蛋白、EZH2和CCSC标志物Dclk1水平升高。AOM/DSS处理的小鼠模拟了CR+AOM处理，因为结肠肿瘤在Ki-67、EZH2和Dclk1方面表现出明显变化，同时伴有F4/80+巨噬细胞浸润、CD3+淋巴细胞浸润以及CD3/β-连环蛋白共定位。肠道和结肠肿瘤对迁移的CSC标志物CD110和CDCP1也呈阳性染色，其中结肠肿瘤还表现出基质阳性。在来自CR感染、CR+AOM或AOM/DSS处理的小鼠的肿瘤以及手术切除的结肠肿瘤/转移性肝脏样本中，p62明显积累且与LC3B和Dclk1共定位。感染CR的小鼠和小鼠在肿瘤内p62与LC3B和Dclk1表现出相似的共定位。在HCT116和SW480细胞中的研究进一步证实了p62/Dclk1共定位以及氯喹/脂多糖诱导的Dclk1启动子活性增加。因此，p62与Dclk1的共定位可能会阻碍Dclk1的清除，从而影响结肠癌的发展和进展。
