PMID- 37645431 OWN - NLM STAT- PubMed-not-MEDLINE LR - 20230831 IS - 2234-943X (Print) IS - 2234-943X (Electronic) IS - 2234-943X (Linking) VI - 13 DP - 2023 TI - TAF1B depletion leads to apoptotic cell death by inducing nucleolar stress and activating p53-miR-101 circuit in hepatocellular carcinoma. PG - 1203775 LID - 10.3389/fonc.2023.1203775 [doi] LID - 1203775 AB - BACKGROUND: TAF1B (TATA Box Binding Protein (TBP)-Associated Factor) is an RNA polymerase regulating rDNA activity, stress response, and cell cycle. However, the function of TAF1B in the progression of hepatocellular carcinoma (HCC) is unknown. OBJECTIVE: In this study, we intended to characterize the crucial role and molecular mechanisms of TAF1B in modulating nucleolar stress in HCC. METHODS: We analyzed the differential expression and prognostic value of TAF1B in hepatocellular carcinoma based on The Cancer Genome Atlas (TCGA) database, tumor and paraneoplastic tissue samples from clinical hepatocellular carcinoma patients, and typical hepatocellular carcinoma. We detected cell proliferation and apoptosis by lentiviral knockdown of TAF1B expression levels in HepG2 and SMMC-7721 cells using clone formation, apoptosis, and Western blotting (WB) detection of apoptosis marker proteins. Simultaneously, we investigated the influence of TAF1B knockdown on the function of the pre-initiation complex (PIC) by WB, and co-immunoprecipitation (Co-IP) and chromatin immunoprecipitation (ChIP) assays verified the interaction between the complexes and the effect on rDNA activity. Immunofluorescence assays measured the expression of marker proteins of nucleolus stress, fluorescence in situ hybridization (FISH) assays checked the rDNA activity, and qRT-PCR assays tested the pre-rRNA levels. Regarding molecular mechanisms, we investigated the role of p53 and miR-101 in modulating nucleolar stress and apoptosis. Finally, the impact of TAF1B knockdown on tumor growth, apoptosis, and p53 expression was observed in xenograft tumors. RESULT: We identified that TAF1B was highly expressed in hepatocellular carcinoma and associated with poor prognosis in HCC patients. TAF1B depletion modulated nucleolar stress and apoptosis in hepatocellular carcinoma cells through positive and negative feedback from p53-miR-101. RNA polymerase I transcription repression triggered post-transcriptional activation of miR-101 in a p53-dependent manner. In turn, miR-101 negatively feeds back through direct inhibition of the p53-mediated PARP pathway. CONCLUSION: These findings broaden our comprehension of the function of TAF1B-mediated nucleolar stress in hepatocellular carcinoma and may offer new biomarkers for exploring prospective therapeutic targets in HCC. CI - Copyright (c) 2023 Chen, Gao, Jiang, Sheng, Wu, Zheng, Zhai, Yuan, Liu, Xu, Qian, Xu, Fang and Zhang. FAU - Chen, Hang-Fei AU - Chen HF AD - The 2nd Clinical Medical College, Zhejiang Chinese Medical University, Hangzhou, China. AD - Core Facility, The Quzhou Affiliated Hospital of Wenzhou Medical University, Quzhou People's Hospital, Quzhou, China. FAU - Gao, Dan-Dan AU - Gao DD AD - Core Facility, The Quzhou Affiliated Hospital of Wenzhou Medical University, Quzhou People's Hospital, Quzhou, China. FAU - Jiang, Xin-Qing AU - Jiang XQ AD - The 2nd Clinical Medical College, Zhejiang Chinese Medical University, Hangzhou, China. FAU - Sheng, Hao AU - Sheng H AD - Department of Anus & Intestine Surgery, The First People's Hospital of Jiande, Hangzhou, Zhejiang, China. FAU - Wu, Qi AU - Wu Q AD - Core Facility, The Quzhou Affiliated Hospital of Wenzhou Medical University, Quzhou People's Hospital, Quzhou, China. FAU - Zheng, Quan AU - Zheng Q AD - Core Facility, The Quzhou Affiliated Hospital of Wenzhou Medical University, Quzhou People's Hospital, Quzhou, China. FAU - Zhai, Qiao-Cheng AU - Zhai QC AD - Core Facility, The Quzhou Affiliated Hospital of Wenzhou Medical University, Quzhou People's Hospital, Quzhou, China. FAU - Yuan, Lei AU - Yuan L AD - Department of Hepatobiliary Surgery, The Quzhou Affiliated Hospital of Wenzhou Medical University, Quzhou People's Hospital, Quzhou, China. FAU - Liu, Ming AU - Liu M AD - The Joint Innovation Center for Engineering in Medicine, Quzhou People's Hospital, Quzhou, China. FAU - Xu, Li-Feng AU - Xu LF AD - The Joint Innovation Center for Engineering in Medicine, Quzhou People's Hospital, Quzhou, China. FAU - Qian, Mao-Xiang AU - Qian MX AD - Institute of Pediatrics and Department of Hematology and Oncology, National Children's Medical Center, Children's Hospital of Fudan University, Institutes of Biomedical Sciences, Fudan University, Shanghai, China. AD - Center for Precision Medicine, The Quzhou Affiliated Hospital of Wenzhou Medical University, Quzhou People's Hospital, Quzhou, China. FAU - Xu, Heng AU - Xu H AD - Center for Precision Medicine, The Quzhou Affiliated Hospital of Wenzhou Medical University, Quzhou People's Hospital, Quzhou, China. AD - Department of Laboratory Medicine, West China Hospital, Sichuan University, Chengdu, Sichuan, China. FAU - Fang, Jian AU - Fang J AD - Department of Hepatobiliary Surgery, The Quzhou Affiliated Hospital of Wenzhou Medical University, Quzhou People's Hospital, Quzhou, China. FAU - Zhang, Feng AU - Zhang F AD - The 2nd Clinical Medical College, Zhejiang Chinese Medical University, Hangzhou, China. AD - Core Facility, The Quzhou Affiliated Hospital of Wenzhou Medical University, Quzhou People's Hospital, Quzhou, China. AD - Center for Precision Medicine, The Quzhou Affiliated Hospital of Wenzhou Medical University, Quzhou People's Hospital, Quzhou, China. LA - eng PT - Journal Article DEP - 20230814 PL - Switzerland TA - Front Oncol JT - Frontiers in oncology JID - 101568867 PMC - PMC10461479 OTO - NOTNLM OT - RNA polymerase I OT - TAF1B OT - hepatocellular carcinoma OT - miR-101 OT - nucleolar stress OT - p53 COIS- The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. EDAT- 2023/08/30 06:47 MHDA- 2023/08/30 06:48 PMCR- 2023/01/01 CRDT- 2023/08/30 03:52 PHST- 2023/04/11 00:00 [received] PHST- 2023/07/14 00:00 [accepted] PHST- 2023/08/30 06:48 [medline] PHST- 2023/08/30 06:47 [pubmed] PHST- 2023/08/30 03:52 [entrez] PHST- 2023/01/01 00:00 [pmc-release] AID - 10.3389/fonc.2023.1203775 [doi] PST - epublish SO - Front Oncol. 2023 Aug 14;13:1203775. doi: 10.3389/fonc.2023.1203775. eCollection 2023.