Characterization of the dehydrogenase-reductase DHRS2 and its involvement in histone deacetylase inhibition in urological malignancies.

BACKGROUND: Being implicated during tumor migration, invasion, clonogenicity, and proliferation, the nicotinamide adenine dinucleotide (NAD)/-phosphate (NADP)-dependent dehydrogenase/reductase member 2 (DHRS2) has been considered to be induced upon inhibition of histone deacetylases (HDACi). In this study, we evaluated the current knowledge on the underlying mechanisms of the (epi)genetic regulation of DHRS2, as well as its function during tumor progression. METHODS: DHRS2 expression was evaluated on mRNA- and protein-level upon treatment with HDACi by means of qRT-PCR and western blot analyses, respectively. Re-analysis of RNA-sequencing data gained insight into expression of specific DHRS2 isoforms, while re-analysis of ATAC-sequencing data shed light on the chromatin accessibility at the DHRS2 locus. Further examination of the energy and lipid metabolism of HDACi-treated urologic tumor cells was performed using liquid chromatography-mass spectrometry. RESULTS: Enhanced DHRS2 expression levels upon HDACi treatment were directly linked to an enhanced chromatin accessibility at the DHRS2 locus. Particularly the DHRS2 ENST00000250383.11 protein-coding isoform was increased upon HDACi treatment. Application of the HDACi quisinostat only mildly influenced the energy metabolism of urologic tumor cells, though, the analysis of the lipid metabolism showed diminished sphingosine levels, as well as decreased S1P levels. Also the ratios of S1P/sphingosine and S1P/ceramides were reduced in all four quisinostat-treated urologic tumor cells. CONCLUSIONS: With the emphasis on urologic malignancies (testicular germ cell tumors, urothelial, prostate, and renal cell carcinoma), this study concluded that elevated DHRS2 levels are indicative of a successful HDACi treatment and, thereby offering a novel putative predictive biomarker.

Epigenetic regulation of DHRS2 by SUV420H2 inhibits cell apoptosis in renal cell carcinoma.

Renal cell carcinoma (RCC), also known as kidney cancer, is a common malignant tumor of the urinary system. While surgical treatment is essential, novel therapeutic targets and corresponding drugs for RCC are still needed due to the high relapse rate and low five-year survival rate. In this study, we found that SUV420H2 is overexpressed in renal cancers and that high SUV420H2 expression is associated with a poor prognosis, as evidenced by RCC RNA-seq results derived from the TCGA. SUV420H2 knockdown using siRNA led to growth suppression and cell apoptosis in the A498 cell line. Furthermore, we identified DHRS2 as a direct target of SUV420H2 in the apoptosis process through a ChIP assay with a histone 4 lysine 20 (H4K20) trimethylation antibody. Rescue experiments showed that cotreatment with siSUV420H2 and siDHRS2 attenuated cell growth suppression induced by SUV420H2 knockdown only. Additionally, treatment with the SUV420H2 inhibitor A-196 induced cell apoptosis via upregulation of DHRS2. Taken together, our findings suggest that SUV420H2 may be a potential therapeutic target for the treatment of renal cancer.

Acute HSF1 depletion induces cellular senescence through the MDM2-p53-p21 pathway in human diploid fibroblasts.

Heat shock transcription factor 1 (HSF1) regulates the expression of a wide array of genes, controls the expression of heat shock proteins (HSPs) as well as cell growth. Although acute depletion of HSF1 induces cellular senescence, the underlying mechanisms are poorly understood. Here, we report that HSF1 depletion-induced senescence (HDIS) of human diploid fibroblasts (HDFs) was independent of HSP-mediated proteostasis but dependent on activation of the p53-p21 pathway, partly because of the increased expression of dehydrogenase/reductase 2 (DHRS2), a putative MDM2 inhibitor. We observed that HDIS occurred without decreased levels of major HSPs or increased proteotoxic stress in HDFs. Additionally, VER155008, an inhibitor of HSP70 family proteins, increased proteotoxicity and suppressed cell growth but failed to induce senescence. Importantly, we found that activation of the p53-p21 pathway resulting from reduced MDM2-dependent p53 degradation was required for HDIS. Furthermore, we provide evidence that increased DHRS2 expression contributes to p53 stabilization and HDIS. Collectively, our observations uncovered a molecular pathway in which HSF1 depletion-induced DHRS2 expression leads to activation of the MDM2-p53-p21 pathway required for HDIS.

Deciphering the molecular effects of romidepsin on germ cell tumours: DHRS2 is involved in cell cycle arrest but not apoptosis or induction of romidepsin effectors.

Testicular germ cell tumours (GCTs) mostly affect young men at age 17-40. Although high cure rates can be achieved by orchiectomy and chemotherapy, GCTs can still be a lethal threat to young patients with metastases or therapy resistance. Thus, alternative treatment options are needed. Based on studies utilising GCT cell lines, the histone deacetylase inhibitor romidepsin is a promising therapeutic option, showing high toxicity at very low doses towards cisplatin-resistant GCT cells, but not fibroblasts or Sertoli cells. In this study, we extended our analysis of the molecular effects of romidepsin to deepen our understanding of the underlying mechanisms. Patients will benefit from these analyses, since detailed knowledge of the romidepsin effects allows for a better risk and side-effect assessment. We screened for changes in histone acetylation of specific lysine residues and analysed changes in the DNA methylation landscape after romidepsin treatment of the GCT cell lines TCam-2, 2102EP, NCCIT and JAR, while human fibroblasts were used as controls. In addition, we focused on the role of the dehydrogenase/reductase DHRS2, which was strongly up-regulated in romidepsin treated cells, by generating DHRS2-deficient TCam-2 cells using CRISPR/Cas9 gene editing. We show that DHRS2 is dispensable for up-regulation of romidepsin effectors (GADD45B, DUSP1, ZFP36, ATF3, FOS, CDKN1A, ID2) but contributes to induction of cell cycle arrest. Finally, we show that a combinatory treatment of romidepsin plus the gluccocorticoid dexamethasone further boosts expression of the romidepsin effectors and reduces viability of GCT cells more strongly than under single agent treatment. Thus, romidepsin and dexamethasone might represent a new combinatorial approach for treatment of GCT.

HOXA13 contributes to gastric carcinogenesis through DHRS2 interacting with MDM2 and confers 5-FU resistance by a p53-dependent pathway.

5-FU-based chemotherapy is recently most recommended as the first-line treatment for gastric cancer (GC). However, 5-FU resistance is common for many postoperative GC patients. Homeobox A13 (HOXA13) is a member of homeobox genes highly expressed in many human tumors. Its potential roles and mechanisms of resistance to 5-FU in GC are poorly understood. In this study, we discovered that HOXA13 played an oncogenic role in vivo and in vitro. The patients with HOXA13 overexpression were closely related with poor prognosis and more prone to be resistant to 5-FU. Moreover, dehydrogenase/reductase 2 (DHRS2) was identified as a downstream gene of HOXA13. HOXA13 played a role of carcinogenesis through directly down-regulating DHRS2 to increase MDM2. Furthermore, HOXA13 conferred 5-FU resistance through MRP1 by a p53-dependent pathway. Therefore, HOXA13 might serve as a potential signature that recognized patients who were insensitive to 5-FU, and timely recommended them to other chemotherapy regimens.

STAMBPL1 promotes the progression of lung adenocarcinoma by inhibiting DHRS2 expression.

BACKGROUND: Lung cancer is responsible for the majority of cancer deaths in the world. We found a significant increase of STAMBPL1 expression in lung adenocarcinoma (LUAD) tissues and cells. However, its mechanism has not been clarified. METHODS: LUAD tissues and adjacent normal tissues were collected from 62 patients treated in the First Affiliated Hospital of Wenzhou Medical University from August 2018 to August 2021. In vivo, the clinical data and STAMBPL1 expression of 62 patients with LUAD were analyzed by qPCR. In vitro, cell experiments were carried out after STAMBPL1 knockdown in A549 and H1299 cells to determine cell growth, migration rate, evasiveness, colony-forming ability, and apoptosis. Gene sequencing was used to explore the expression of various genes in A549 and H1299 cells to verify that DHRS2 was up-regulated after STAMBPL1 knockdown; cell experiments further detected the role of the DHRS2 gene after DHRS2 overexpression in A549 and H1299 cells. A rescue experiment was conducted to certify that STAMBPL1 promotes NSCLC progression by regulating DHRS2 expression. RESULTS: After STAMBPL1 knockdown by siRNA. Migration, invasion, colony formation, and proliferation of siRNA groups were suppressed than those of NC groups in A549 and H1299 cells, while the cell apoptosis rate of siRNA groups increased significantly. By using gene-sequence analysis, we found that the expression level of the DHRS2 gene was up-regulated in STAMBPL1 siRNA groups, compared with STAMBPL1 NC (negative control) groups in A549 and H1299, which was verified by qPCR and WB. Further experiments showed that the DHRS2 OE group was suppressed in cell proliferation, migration, and invasion in the A549 and H1299 cell lines compared to the DHRS2 NC group, while DHRS2 OE group was significantly enhanced in the cell apoptosis in the A549 and H1299 cell lines. According to the rescue experiment, cell proliferation, migration, and invasion of the STAMBPL1 SI+DHRS2 SI group were enhanced compared with the STAMBPL1 SI+DHRS2 NC group in A549 and H1299 cells, while the STAMBPL1 SI+DHRS2 OE group were further decreased. CONCLUSIONS: The expression of STAMBPL1 mRNA is significantly up-regulated in LUAD, promoting the progression of LUAD by down-regulating the expression of DHRS2 and acting as a potential biomarker of LUAD.

Regulatory mechanism of DHRS2-modified human umbilical cord mesenchymal stem cells-derived exosomes in prostate cancer cell proliferation and apoptosis.

Prostate cancer (PCa) is a prevalent cause of morbidity and mortality. DHRS2-modified human umbilical cord mesenchymal stem cells-derived exosomes (hUC-MSCs-derived exos) function in PCa. We explored the mechanism of DHRS2-modified hUC-MSCs-derived exos in PCa cell malignant behaviors. DHRS2 expression levels in WPMY-1 cells and 4 PCa cell lines were detected by RT-qPCR and Western blot. 22Rv1/DU145 cells with high/low DHRS2 expression were selected to establish the low/high DHRS2 expression models by transfection. Cell proliferation and apoptosis were detected by CCK-8, colony formation assays, and flow cytometry. hUC-MSCs were identified by oil red O, alizarin staining, and flow cytometry. Exos were extracted from hUC-MSCs by ultracentrifugation and identified by transmission electron microscopy, Nano series-Nano-ZS, and Western blot. DU145 cells were selected for in vitro study to further study the effects of DHRS2-modified exos on cell proliferation and apoptosis. The effect of DHRS2-modified exos on cell cycle distribution was detected by flow cytometry. DHRS2 was repressed in PCa cells. DHRS2 overexpression suppressed PCa cell proliferation and promoted apoptosis. Exos were successfully isolated from hUC-MSC. DHRS2-modified hUC-MSCs-derived exos carried DHRS2 into PCa cells and blocked malignant behaviors. Briefly, DHRS2 was repressed in PCa cells. DHRS2-modified hUC-MSCs-derived exos blocked PCa cell proliferation and enhanced apoptosis.

Emerging roles of dehydrogenase/reductase member 2 (DHRS2) in the pathology of disease.

Dehydrogenase/reductase member 2 (DHRS2) belongs to the short-chain dehydrogenase/reductase (SDR) family. It was initially isolated from the nuclear extract of hepatocellular carcinoma HepG2 cells and was identified as a specific cell cycle regulator. DHRS2 is a reduced nicotinamide adenine dinucleotide phosphate (NADPH)-dependent carbonyl reductase and catalyzes the reduction of dicarbonyl compounds. It is also functionally active in lipid metabolism and acts as a metabolic enzyme of hormones. Recent studies have shown that DHRS2 reprograms lipid metabolism and redox homeostasis to regulate proliferation, migration, invasion, and drug resistance of cancer cells. Here, we describe the structure, organelle localization and function of DHRS2, and also highlight its roles in the pathologic progression of diseases.

Decreased DHRS2 expression is associated with HDACi resistance and poor prognosis in ovarian cancer.

Histone deacetylases (HDACs) have been linked to a variety of cancers, and HDAC inhibitors (HDACi) are a promising class of drugs that have demonstrated anti-cancer effects. However, we have little knowledge regarding the selection and application of HDAC inhibitors to the personalized treatment of ovarian cancer (OC). Here, we report a correlation between the high expression of HDACs and poor outcomes in OC patients, which reveals that HDACi are a class of agents that show great promise for the treatment of OC. Furthermore, we found that HDACi increased both the mRNA and protein levels of DHRS2, which has been shown to be closely linked to HDACi sensitivity when it is highly expressed, especially in ovarian cancer cells. Consistently, we found that suppression of DHRS2 reduced the sensitivity of OC cells to HDAC inhibitors via attenuation of the inhibitory effects of HDAC inhibitors on Mcl-1 in vitro. Our study demonstrated that DHRS2 expression was decreased in OC tissues and that high expression of DHRS2 was correlated with better outcomes in OC patients. In addition, DHRS2 expression was closely related to the effects of chemotherapy. Our study reveals the role of DHRS2 in cell apoptosis induced by HDAC inhibitors and explores the clinical attributes of DHRS2 in OC from a new perspective, suggesting that OC patients with high DHRS2 expression may benefit from treatment with HDAC inhibitors.

LEF1 Induces DHRS2 Gene Expression in Human Acute Leukemia Jurkat T-Cells

Objective: T-cell acute lymphoblastic leukemia (T-ALL) is an aggressive disease resulting from the accumulation of genetic changes that affect the development of T-cells. The precise role of lymphoid enhancer-binding factor 1 (LEF1) in T-ALL has been controversial since both overexpression and inactivating LEF1 mutations have been reported to date. Here, we investigate the potential gene targets of LEF1 in the Jurkat human T-cell leukemia cell line. Materials and Methods: We used small interfering RNA (siRNA) technology to knock down LEF1 in Jurkat cells and then compared the gene expression levels in the LEF1 knockdown cells with non-targeting siRNA-transfected and non-transfected cells by employing microarray analysis. Results: We identified DHRS2, a tumor suppressor gene, as the most significantly downregulated gene in LEF1 knockdown cells, and we further confirmed its downregulation by real-time quantitative polymerase chain reaction (qRT-PCR) in mRNA and at protein level by western blotting. Conclusion: Our results revealed that DHRS2 is positively regulated by LEF1 in Jurkat cells, which indicates the capability of LEF1 as a tumor suppressor and, together with previous reports, suggests that LEF1 exhibits a regulatory role in T-ALL via not only its oncogenic targets but also tumor suppressor genes.

DHRS2 mediates cell growth inhibition induced by Trichothecin in nasopharyngeal carcinoma.

BACKGROUND: Cancer is fundamentally a deregulation of cell growth and proliferation. Cancer cells often have perturbed metabolism that leads to the alteration of metabolic intermediates. Dehydrogenase/reductase member 2 (DHRS2) belongs to short-chain alcohol dehydrogenase/reductase (SDR) superfamily, which is functionally involved in a number of intermediary metabolic processes and in the metabolism of lipid signaling molecules. DHRS2 displays closely association with the inhibition of cell proliferation, migration and quiescence in cancers. METHODS: 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4- sulfophenyl)-2H-tetrazolium (MTS), 5-ethynyl-2'-deoxyuridine (EdU) and colony formation assays were applied to evaluate the proliferative ability of nasopharyngeal carcinoma (NPC) cells. We performed lipid metabolite profiling using gas chromatography coupled with mass spectrometry (GC/MS) to identify the proximal metabolite changes linked to DHRS2 overexpression. RNA sequencing technique combined with differentially expressed genes analysis was applied to identify the expression of genes responsible for the anti-tumor effect of trichothecin (TCN), a natural sesquiterpenoid compound isolated from an endophytic fungus. RESULTS: Our current findings reveal that DHRS2 affects lipid metabolite profiling to induce cell cycle arrest and growth inhibition in NPC cells. Furthermore, we demonstrate that TCN is able to induce growth inhibition of NPC in vitro and in vivo by up-regulating DHRS2. CONCLUSIONS: Our report suggests that activating DHRS2 to reprogram lipid homeostasis may be a target for the development of targeted therapies against NPC. Moreover, TCN could be exploited for therapeutic gain against NPC by targeting DHRS2 and it may also be developed as a tool to enhance understanding the biological function of DHRS2.