Theranostics 2020; 10(21):9495-9511. doi:10.7150/thno.45631
DNA methylation downregulated ZDHHC1 suppresses tumor growth by altering cellular metabolism and inducing oxidative/ER stress-mediated apoptosis and pyroptosis
1. Key Laboratory of Molecular Oncology and Epigenetics, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China.
2. MOE Key Laboratory of Molecular Biology for Infectious Diseases, Department of Infectious Disease, Chongqing Medical University, China.
3. Lovelace Respiratory Research Institute, Albuquerque, New Mexico, USA.
4. Cancer Epigenetics Laboratory, Department of Clinical Oncology, State Key Laboratory of Translational Oncology, Sir YK Pao Center for Cancer and Li Ka Shing Institute of Health Sciences, The Chinese University of Hong Kong, Hong Kong.
*First authors with equal contributions to this work.
Le X, Mu J, Peng W, Tang J, Xiang Q, Tian S, Feng Y, He S, Qiu Z, Ren G, Huang A, Lin Y, Tao Q, Xiang T. DNA methylation downregulated ZDHHC1 suppresses tumor growth by altering cellular metabolism and inducing oxidative/ER stress-mediated apoptosis and pyroptosis. Theranostics 2020; 10(21):9495-9511. doi:10.7150/thno.45631. Available from http://www.thno.org/v10p9495.htm
Cancer progression is an intricate biological process profiled by not only unscheduled proliferation, but also altered metabolism mechanisms. In this article, we introduced a novel tumor suppressor gene (TSG), Zinc Finger DHHC-Type Containing 1 (ZDHHC1, also known as ZNF377), frequently silenced due to epigenetic modification among various cancers, which exerts significant anti-tumor effects through metabolic regulation.
Methods: Quantitative reversed-transcription PCR (qRT-PCR), reverse transcription PCR (RT-PCR) and Western blot were employed to demonstrate transcriptional and protein levels of targeted regulators. Methylation of ZDHHC1 promoter was detected by bisulfite genomic sequencing (BGS) and methylation specific PCR (MSP). Proteomics were analyzed by isobaric tags for relative and absolute quantitation (iTRAQ) and gas chromatography-mass spectrometry (GC-MS) were utilized for metabolomics analysis. Cellular functions were examined via corresponding approaches. Nude mice were used for xenograft tumor models. Indirect immunofluorescence staining was utilized to obtain precise location and expression of target proteins. Oxidative and ER stress indicators were detected using specific kits.
Results: We found that ZDHHC1 expression was frequently silenced in multiple tumor cells and specimens due to methylation. Restoration of ZDHHC1 expression can curb cancer cell progression via stimulating apoptosis and cell cycle arrest, repressing metastasis, and reversing EMT transition and cell stemness. ZDHHC1's salient anti-tumor abilities were recognized in vivo as well. Metabolomic and proteomic analyses predicted inhibitory role of ZDHHC1 in glucose metabolism pathways in a CYGB-dependent manner, and in pentose phosphate pathway (PPP), which was validated by examining altered key factors. Moreover, we unraveled that ZDHHC1 dedicates to the increment of oxidative stress and endoplasmic reticulum (ER) stress to promote pyroptosis for anticancer purposes.
Conclusion: Our study for the first time indicates ZDHHC1 is a potential tumor-suppressor frequently silenced due to promoter methylation, capable of negatively regulating metabolisms of tumor cells while stimulating oxidative stress and ER stress to expedite cell death through induction of pyroptosis and apoptosis, which can be exploited for development of new cancer prevention and therapies.
Keywords: ZDHHC1, ER stress, Oxidative stress, CYGB, zinc finger protein