title: Tazarotene-Induced Gene 1 Enhanced Cervical Cell Autophagy through Transmembrane Protein 192.
abstract: Tazarotene-induced gene 1 (TIG1) is a retinoic acid-inducible protein that is considered a putative tumor suppressor. The expression of TIG1 is decreased in malignant prostate carcinoma or poorly differentiated colorectal adenocarcinoma, but TIG1 is present in benign or well-differentiated tumors. Ectopic TIG1 expression led to suppression of growth in cancer cells. However, the function of TIG1 in cell differentiation is still unknown. Using a yeast two-hybrid system, we found that transmembrane protein 192 (TMEM192) interacted with TIG1. We also found that both TIG1A and TIG1B isoforms interacted and co-localized with TMEM192 in HtTA cervical cancer cells. The expression of TIG1 induced the expression of autophagy-related proteins, including Beclin-1 and LC-3B. The silencing of TMEM192 reduced the TIG1-mediated upregulation of autophagic activity. Furthermore, silencing of either TIG1 or TMEM192 led to alleviation of the upregulation of autophagy induced by all-trans retinoic acid. Our results demonstrate that the expression of TIG1 leads to cell autophagy through TMEM192. Our study also suggests that TIG1 and TMEM192 play an important role in the all-trans retinoic acid-mediated upregulation of autophagic activity.
authors.affiliation: Department of Internal Medicine, Taipei Tzuchi Hospital, The Buddhist Tzuchi Medical Foundation, New Taipei City 231, Taiwan.
authors.forename: Rong-Yaun
authors.initials: RY
authors.lastname: Shyu
authors.affiliation: Department of Dermatology, Taipei Tzuchi Hospital, The Buddhist Tzuchi Medical Foundation, New Taipei City 231, Taiwan.
authors.forename: Chun-Hua
authors.initials: CH
authors.lastname: Wang
authors.affiliation: Department of Surgery, Tri-Service General Hospital, National Defense Medical Center, Taipei 114, Taiwan.
authors.forename: Chang-Chieh
authors.initials: CC
authors.lastname: Wu
authors.affiliation: Department of Research, Taipei Tzuchi Hospital, The Buddhist Tzuchi Medical Foundation, New Taipei City 231, Taiwan.
authors.forename: Mao-Liang
authors.initials: ML
authors.lastname: Chen
authors.affiliation: Department of Research, Taipei Tzuchi Hospital, The Buddhist Tzuchi Medical Foundation, New Taipei City 231, Taiwan.
authors.forename: Ming-Cheng
authors.initials: MC
authors.lastname: Lee
authors.affiliation: Radiation Biology Core Laboratory, Institute for Radiological Research, Chang Gung University/Chang Gung Memorial Hospital, Linkou, Taoyuan 333, Taiwan.
authors.forename: Lu-Kai
authors.initials: LK
authors.lastname: Wang
authors.affiliation: Department of Research, Taipei Tzuchi Hospital, The Buddhist Tzuchi Medical Foundation, New Taipei City 231, Taiwan.
authors.forename: Shun-Yuan
authors.initials: SY
authors.lastname: Jiang
authors.affiliation: Department of Research, Taipei Tzuchi Hospital, The Buddhist Tzuchi Medical Foundation, New Taipei City 231, Taiwan.
authors.forename: Fu-Ming
authors.initials: FM
authors.lastname: Tsai
mesh_terms: D001343:Autophagy / Q000502:physiology; D000071186:Beclin-1 / Q000096:biosynthesis / Q000378:metabolism; D045744:Cell Line, Tumor; D005260:Female; D006367:HeLa Cells; D006801:Humans; D008565:Membrane Proteins / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism*; D018613:Microscopy, Confocal; D008869:Microtubule-Associated Proteins / Q000096:biosynthesis / Q000378:metabolism; D014162:Transfection; D014212:Tretinoin / Q000494:pharmacology; D002583:Uterine Cervical Neoplasms / Q000235:genetics / Q000378:metabolism* / Q000473:pathology*
chemical_list: C491997:BECN1 protein, human; D000071186:Beclin-1; C502070:MAP1LC3B protein, human; D008565:Membrane Proteins; D008869:Microtubule-Associated Proteins; C452562:RARRES1 protein, human; C557523:transmembrane protein 192, human; D014212:Tretinoin
keywords: Beclin-1; LC3B; all-trans retinoic acid; autophagy; tazarotene-induced gene 1; transmembrane protein 192