Role of Hydroxysteroid Dehydrogenase-Like 2 (HSDL2) in Human Ovarian Cancer

HSDL2 links nutritional cues to bile acid and cholesterol homeostasis

In response to energy and nutrient shortage, the liver triggers several catabolic processes to promote survival. Despite recent progress, the precise molecular mechanisms regulating the hepatic adaptation to fasting remain incompletely characterized. Here, we report the identification of hydroxysteroid dehydrogenase-like 2 (HSDL2) as a mitochondrial protein highly induced by fasting. We show that the activation of PGC1α-PPARα and the inhibition of the PI3K-mTORC1 axis stimulate HSDL2 expression in hepatocytes. We found that HSDL2 depletion decreases cholesterol conversion to bile acids (BAs) and impairs FXR activity. HSDL2 knockdown also reduces mitochondrial respiration, fatty acid oxidation, and TCA cycle activity. Bioinformatics analyses revealed that hepatic Hsdl2 expression positively associates with the postprandial excursion of various BA species in mice. We show that liver-specific HSDL2 depletion affects BA metabolism and decreases circulating cholesterol levels upon refeeding. Overall, our report identifies HSDL2 as a fasting-induced mitochondrial protein that links nutritional signals to BAs and cholesterol homeostasis.

Using human genetics to understand the phenotypic association between chronotype and breast cancer

Little is known regarding the shared genetic influences underlying the observed phenotypic association between chronotype and breast cancer in women. Leveraging summary statistics from the hitherto largest genome-wide association study conducted in each trait, we investigated the genetic correlation, pleiotropic loci, and causal relationship of chronotype with overall breast cancer, and with its subtypes defined by the status of oestrogen receptor. We identified a negative genomic correlation between chronotype and overall breast cancer (r g  = -0.06, p = 3.00 × 10-4), consistent across oestrogen receptor-positive (r g  = -0.05, p = 3.30 × 10-3) and oestrogen receptor-negative subtypes (r g  = -0.05, p = 1.11 × 10-2). Five specific genomic regions were further identified as contributing a significant local genetic correlation. Cross-trait meta-analysis identified 78 loci shared between chronotype and breast cancer, of which 23 were novel. Transcriptome-wide association study revealed 13 shared genes, targeting tissues of the nervous, cardiovascular, digestive, and exocrine/endocrine systems. Mendelian randomisation demonstrated a significantly reduced risk of overall breast cancer (odds ratio 0.89, 95% confidence interval 0.83-0.94; p = 1.30 × 10-4) for genetically predicted morning chronotype. No reverse causality was found. Our work demonstrates an intrinsic link underlying chronotype and breast cancer, which may provide clues to inform management of sleep habits to improve female health.

ABCD1 as a Novel Diagnostic Marker for Solid Pseudopapillary Neoplasm of the Pancreas

The diagnosis of solid pseudopapillary neoplasm of the pancreas (SPN) can be challenging due to potential confusion with other pancreatic neoplasms, particularly pancreatic neuroendocrine tumors (NETs), using current pathological diagnostic markers. We conducted a comprehensive analysis of bulk RNA sequencing data from SPNs, NETs, and normal pancreas, followed by experimental validation. This analysis revealed an increased accumulation of peroxisomes in SPNs. Moreover, we observed significant upregulation of the peroxisome marker ABCD1 in both primary and metastatic SPN samples compared with normal pancreas and NETs. To further investigate the potential utility of ABCD1 as a diagnostic marker for SPN via immunohistochemistry staining, we conducted verification in a large-scale patient cohort with pancreatic tumors, including 127 SPN (111 primary, 16 metastatic samples), 108 NET (98 nonfunctional pancreatic neuroendocrine tumor, NF-NET, and 10 functional pancreatic neuroendocrine tumor, F-NET), 9 acinar cell carcinoma (ACC), 3 pancreatoblastoma (PB), 54 pancreatic ductal adenocarcinoma (PDAC), 20 pancreatic serous cystadenoma (SCA), 19 pancreatic mucinous cystadenoma (MCA), 12 pancreatic ductal intraepithelial neoplasia (PanIN) and 5 intraductal papillary mucinous neoplasm (IPMN) samples. Our results indicate that ABCD1 holds promise as an easily applicable diagnostic marker with exceptional efficacy (AUC=0.999, sensitivity=99.10%, specificity=100%) for differentiating SPN from NET and other pancreatic neoplasms through immunohistochemical staining.

HSDL2 knockdown promotes the progression of cholangiocarcinoma by inhibiting ferroptosis through the P53/SLC7A11 axis

BACKGROUND

Human hydroxysteroid dehydrogenase-like 2 (HSDL2), which regulates cancer progression, is involved in lipid metabolism. However, the role of HSDL2 in cholangiocarcinoma (CCA) and the mechanism by which it regulates CCA progression by modulating ferroptosis are unclear.

METHODS

HSDL2 expression levels in CCA cells and tissues were determined by quantitative real-time polymerase chain reaction (qRT-PCR), western blotting, and immunohistochemistry. The overall survival and disease-free survival of patients with high vs. low HSDL2 expression were evaluated using Kaplan-Meier curves. The proliferation, migration, and invasion of CCA cells were assessed using Cell Counting Kit-8, colony formation, 5-ethynyl-2'-deoxyuridine DNA synthesis, and transwell assays. The effect of p53 on tumor growth was explored using a xenograft mouse model. The expression of SLC7A11 in patients with CCA was analyzed using immunofluorescence. Ferroptosis levels were measured by flow cytometry, malondialdehyde assay, and glutathione assay. HSDL2-regulated signaling pathways were analyzed by transcriptome sequencing. The correlation between p53 and SLC7A11 was assessed using bioinformatics and luciferase reporter assays.

RESULTS

HSDL2 expression was lower in primary human CCA tissues than in matched adjacent non-tumorous bile duct tissues. HSDL2 downregulation was a significant risk factor for shorter overall survival and disease-free survival in patients with CCA. In addition, HSDL2 knockdown enhanced the proliferation, migration, and invasion of CCA cells. The transcriptome analysis of HSDL2 knockdown cells showed that differentially expressed genes were significantly enriched in the p53 signaling pathway, and HSDL2 downregulation increased SLC7A11 levels. These findings were consistent with the qRT-PCR and western blotting results. Other experiments showed that p53 expression modulated the effect of HSDL2 on CCA proliferation in vivo and in vitro and that p53 bound to the SLC7A11 promoter to inhibit ferroptosis.

CONCLUSIONS

HSDL2 knockdown promotes CCA progression by inhibiting ferroptosis through the p53/SLC7A11 axis. Thus, HSDL2 is a potential prognostic marker and therapeutic target for CCA.

Expression Profile of Hydroxysteroid Dehydrogenase-like 2 in Polychaete Perinereis aibuhitensis in Response to BPA

Hydroxysteroid dehydrogenases (HSDs) play an important role in the metabolism of steroids and xenobiotics. However, the function of HSDs in invertebrates is unclear. In this study, we cloned the hydroxysteroid dehydrogenase-like 2 (HSDL2) gene in Perinereis aibuhitensis, which is 1652 bp in length, encoding 400 amino acids. This sequence contains conserved short-chain dehydrogenase and sterol carrier protein-2 domain, and the alignment analysis showed its close relationship with other invertebrate HSDL2. Further, the tissue distribution analysis of the HSDL2 gene showed it is expressed strongly in the intestine. The expression level of HSDL2 after inducement with bisphenol A (BPA) was also detected both at transcriptional and translational levels. The results inferred that BPA exposure can induce HSDL2 expression, and the inductive effect was obvious in the high-concentration BPA group (100 μg/L). In summary, our results showed the detoxification function of HSDL2 in polychaetes.

Hydroxysteroid Dehydrogenase Like 2 Promotes the Invasion and Migration of Osteosarcoma by Regulating Fibroblast Growth Factor Receptor 4

We aimed to explore the expression characteristics of HSDL2 in osteosarcoma (OS) as well as the underlying mechanism. A total of 42 OS patients’ tissue samples were collected. HSDL2 level was markedly higher in OS tissues as well as OS cell lines. Besides, patients with high HSDL2 expression had a higher incidence of distant metastasis and a lower overall survival rate. Furthermore, the ability of OS cells to proliferate, invade and metastasize was markedly reduced after HSDL2 knockdown; however, the overexpression of HSDL2 could markedly increase the proliferative, invasive and metastasis ability of OS cells. In addition, HSDL2 can target FGFR4. Furthermore, FGFR4 expression was markedly decreased after HSDL2 knockdown, besides, HSDL2 and FGFR4 expressions were positively correlated in OS tissues. In addition, the recovery experiments suggested that HSDL2 and FGFR4 had a mutual regulation, thereby jointly promoting the invasive and migration ability of OS. HSDL2 expression was markedly increased in OS tissues as well as OS cell lines, which was markedly related to distant metastasis along with poor prognosis of OS patients. Besides, HSDL2 may promote OS progression by increasing the FGFR4 expression.

MiR-26a-5p regulates proliferation, apoptosis, migration and invasion via inhibiting hydroxysteroid dehydrogenase like-2 in cervical cancer cell

Background

Evidences have indicated that miR-26a-5p regulates the malignant properties of various tumor cells. However, the influences of miR-26a-5p on proliferation, apoptosis and invasion are still vague in the cervical cancer (CC) cells.

Methods

The miRNA microarray and real-time quantitative PCR (RT-qPCR) analysis were utilized to detect the expression of miR-26a-5p in the patients with CC. Kaplan–Meier plotter was performed to evaluate the overall survival (OS) of the patients with CC. The CCK-8, flow cytometry, transwell and wound healing analyses were respectively used to analyze proliferation, migration and invasion in the CC cells. RT-qPCR, western blot and IHC analysis were executed to measure the expression of hydroxysteroid dehydrogenase like-2 (HSDL2) in the patients with CC. Bioinformatics and luciferase reporter assay were carried out to verify the relationship of miR-26a-5p and HSDL2.

Results

The expression of miR-26a-5p was downregulated and low expression of miR-26a-5p indicated a poor OS in patients with CC. Overexpression of miR-26a-5p significantly inhibited proliferation, migration and invasion, accelerated apoptosis in the Hela and C33A cells. The expression of HSDL2 was upregulated, and negatively correlated with miR-26a-5p in the patients with CC. HSDL2 was directly targeted by miR-26a-5p and rescue experiments displayed that HSDL2 partially abolished proliferation, apoptosis, migration, and invasion induced by miR-26a-5p in CC cells.

Conclusions

MiR-26a-5p alleviated progression of CC by suppressing proliferation, migration and invasion, promoting apoptosis through downregulating HSDL2.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-022-09970-x.

Research Progress in Prognostic Factors and Biomarkers of Ovarian Cancer

Ovarian cancer is a serious threat to women's health; its early diagnosis rate is low and prone to metastasis and recurrence. The current conventional treatment for ovarian cancer is a combination of platinum and paclitaxel chemotherapy based on surgery. The recurrence and progression of ovarian cancer with poor prognosis is a major challenge in treatment. With rapid advances in technology, understanding of the molecular pathways involved in ovarian cancer recurrence and progression has increased, biomarker-guided treatment options can greatly improve the prognosis of patients. This review systematically discusses and summarizes existing and new information on prognostic factors and biomarkers of ovarian cancer, which is expected to improve the clinical management of patients and lead to effective personalized treatment.

Knockdown of HSDL2 inhibits lung adenocarcinoma progression via down-regulating AKT2 expression

The aims of the present study are to investigate the role of hydroxysteroid dehydrogenase-like 2 (HSDL2) in the progression of lung adenocarcinoma and illuminate the underlying molecular mechanisms. ShRNA targeting HSDL2 gene (siHSDL2) was utilized to knockdown (KD) HSDL2 expression. In vitro and in vivo experiments were carried out to investigate the effect of siHSDL2 on the progression of lung adenocarcinoma. Microarray hybridization and gene expression analysis were used to investigate effect of siHSDL2 on mRNA expression profile in lung cancer cell line H1299. Our data demonstrated that HSDL2 was up-regulated in lung adenocarcinoma tissue samples (P<0.001). Patients with high HSDL2 expression in cancer tissues had a worse overall survival (P<0.001). HSDL2 KD not only inhibited the proliferation, cell cycle, apoptosis, clone-formation, invasion and migration of lung adenocarcinoma cells in vitro (P<0.05), but also suppressed the growth and metastasis in vivo (P<0.05). HSDL2 KD resulted in up-regulation of 681 genes and down-regulation of 276 genes. HSDL2 KD down-regulated the protein expression and phosphorylation of protein kinase B β (AKT2) (P<0.001 and P<0.001, respectively) and protein expression of baculoviral IAP repeat-containing 3 (BIRC3; P=0.001), and up-regulated the phosphorylation of ERK (P<0.001). Rescue experiments showed that AKT2 overexpression reversed the suppression effect of siHSDL2 on cell proliferation (P<0.001), invasion (P<0.001) and migration (P<0.001) significantly. HSDL2 functions as an oncogene to promote the growth and metastasis of lung adenocarcinoma via promoting the expression of AKT2.

Lipid metabolism regulator human hydroxysteroid dehydrogenase-like 2 (HSDL2) modulates cervical cancer cell proliferation and metastasis

Human hydroxysteroid dehydrogenase‐like 2 (HSDL2) is a potent regulator in cancers and is also involved in lipid metabolism, but the role of HSDL2 in cervical cancer and whether it regulates the progress of cervical cancer through lipid metabolism remains unclear. In this study, we found that the overexpression of HSDL2 was in relation with cervical cancer progression including lymph nodes metastasis and recurrence. HSDL2 could serve as a novel marker of early diagnosis in cervical cancer. HSDL2 also gave impetus to tumorigenesis by initiating and promoting proliferation, invasion and migration of cervical cancer cells (Hela, C33A and SiHa) through EMT. Interestingly, we also searched that HSDL2 participated in oncogenesis by regulating lipid metabolism. In sum, our results gave the novel insight of HSDL2 functions which could be the potential for being the biomarker of prognosis and new target of therapy.

Perspectives on Organelle Interaction, Protein Dysregulation, and Cancer Disease

In recent decades, compelling evidence has emerged showing that organelles are not static structures but rather form a highly dynamic cellular network and exchange information through membrane contact sites. Although high-throughput techniques facilitate identification of novel contact sites (e.g., organelle-organelle and organelle-vesicle interactions), little is known about their impact on cellular physiology. Moreover, even less is known about how the dysregulation of these structures impacts on cellular function and therefore, disease. Particularly, cancer cells display altered signaling pathways involving several cell organelles; however, the relevance of interorganelle communication in oncogenesis and/or cancer progression remains largely unknown. This review will focus on organelle contacts relevant to cancer pathogenesis. We will highlight specific proteins and protein families residing in these organelle-interfaces that are known to be involved in cancer-related processes. First, we will review the relevance of endoplasmic reticulum (ER)-mitochondria interactions. This section will focus on mitochondria-associated membranes (MAMs) and particularly the tethering proteins at the ER-mitochondria interphase, as well as their role in cancer disease progression. Subsequently, the role of Ca²⁺ at the ER-mitochondria interphase in cancer disease progression will be discussed. Members of the Bcl-2 protein family, key regulators of cell death, also modulate Ca²⁺ transport pathways at the ER-mitochondria interphase. Furthermore, we will review the role of ER-mitochondria communication in the regulation of proteostasis, focusing on the ER stress sensor PERK (PRKR-like ER kinase), which exerts dual roles in cancer. Second, we will review the relevance of ER and mitochondria interactions with other organelles. This section will focus on peroxisome and lysosome organelle interactions and their impact on cancer disease progression. In this context, the peroxisome biogenesis factor (PEX) gene family has been linked to cancer. Moreover, the autophagy-lysosome system is emerging as a driving force in the progression of numerous human cancers. Thus, we will summarize our current understanding of the role of each of these organelles and their communication, highlighting how alterations in organelle interfaces participate in cancer development and progression. A better understanding of specific organelle communication sites and their relevant proteins may help to identify potential pharmacological targets for novel therapies in cancer control.

HSDL2 Acts as a Promoter in Pancreatic Cancer by Regulating Cell Proliferation and Lipid Metabolism

Background

Pancreatic cancer (PC) is a leading cause of cancer mortality worldwide. Hydroxysteroid dehydrogenase like protein 2 (HSDL2) is overexpressed in a variety of malignant tumors and is might be closely related to the development of cancer. It also regulates different metabolism and signaling pathways.

Purpose

The purpose of this research was to find HSDL2 expression levels and investigate its underlying molecular mechanism in PC.

Patients and Methods

In the present study, a total of 66 PC samples and 54 normal tissues were used to examine the expression of HSDL2. In order to gain a broader insight into the molecular mechanism of HSDL2 in PC, the HSDL2 siRNA sequences were transfected into PC cell lines (Bxpc-3 and Panc-1), respectively. Cell proliferation was measured by MTT, colony formation assay and EdU assays. Furthermore, the lipid metabolism process was evaluated by triglyceride and phospholipid assay kits, BODIPY 493/503 staining and the expression of several pivotal lipid metabolic enzymes in PC.

Results

In this study, HSDL2 was highly expressed in PC and connected with shorter overall survival. When HSDL2 was silenced, the cell proliferation was significantly reduced, and the lipid metabolism was further inhibited.

Conclusion

High expression of HSDL2 plays an important role in the progression of PC and might be a potential new biomarker of poor prognosis as well as a therapeutic target in the future.

Silencing of keratin 17 by lentivirus-mediated short hairpin RNA inhibits the proliferation of PANC-1 human pancreatic cancer cells

Keratin 17 (KRT17) has been demonstrated to be a potential biological marker for the prediction of prognosis in particular types of cancer. The aim of the present study was to investigate the molecular mechanisms underlying the function of KRT17 in the pancreatic cancer (PAC) cell line PANC-1 and the potential of KRT17 as a therapeutic target for PAC. KRT17 expression levels were analyzed using quantitative PCR and compared with histological data using bioinformatics tools in PAC samples and three human PAC cell lines. Cell proliferation was determined using an MTT assay, in addition to cell cycle distribution and apoptosis analysis using flow cytometry, colony formation assay using Giemsa staining and cell motility analysis using a Transwell migration assay. Tumor growth was evaluated in vivo in nude mice. The expression levels of a number of signaling molecules were measured to establish the potential mechanism by which silencing KRT17 expression affected PAC PANC-1 cells. Increased levels of KRT17 expression were observed in human PAC compared with normal tissues, as well as in three human PAC cell lines (MIA PaCa-2, PANC-1 and KP-3 cells) compared with the H6c7 human immortal pancreatic duct epithelial cell line. High expression levels of KRT17 in PAC samples were associated with poor overall survival (P=0.036) and disease-free survival (P=0.017). Lentivirus-mediated KRT17 silencing inhibited cell proliferation, colony formation and migration, but promoted apoptosis and resulted in cell cycle arrest in the G₀/G₁ phase in PANC-1 cells. In addition, KRT17 knockdown inhibited in vivo tumor growth. KRT17 knockdown induced dysregulation of ERK1/2 and upregulation of the pro-apoptotic Bcl-2 protein Bad. In conclusion, the present study demonstrated that elevated KRT17 levels are positively associated with pancreatic cancer progression; KRT17 knockdown suppressed cell growth, colony formation, migration and tumor growth, and induced apoptosis and cell cycle arrest, affecting ERK1/2/Bad signaling. Therefore, the results of the present study suggested that KRT17 may be a potential target for the treatment of pancreatic cancer.

Exonuclease 1 (Exo1) Participates in Mammalian Non-Homologous End Joining and Contributes to Drug Resistance in Ovarian Cancer

Background

Exonuclease 1 (Exo1) participates in a variety of DNA damage repair, including mismatch repair, nucleotide excision repair, and homologous recombination. Genetic study in yeast indicates a role of Exo1 in non-homologous end joining (NHEJ), acting as a regulator for accuracy repairing DNA. This study aimed to investigate the effects of human Exo1 in NHEJ and drug resistance in ovarian cells.

Material/Methods

Ectopic expression of Exo1 was carried out using pcDNA3.1-EXO1 plasmid in SKOV3 cells. GST-tagged human Exo1 was purified using pTXB1-gst-EXO1 and the his-tagged-Ku was collected using pET15b.his.Ku. Exo1 and Ku70 proteins expressed in bacteria were harvested and purified. DNA-protein binding was examined using affinity capture assay. The cells were treated using drugs for 72 hours. Then, the viabilities of cells were evaluated with sulforhodamine B cell viability analysis. The protein expression was evaluated using western blot assay.

Results

As expected, human cells that deficient of Exo1 were sensitive to ionizing radiation and DNA damaging drugs (cisplatin and doxorubicin). Cisplatin resistant ovarian cancer cell line and Exo1 deficient cell lines were successfully generated. Exo1 interacts with NHEJ required factor Ku70 and affects NHEJ efficiency. We observed that Exo1 expression level was upregulated in drug resistant cell line and knockdown of Exo1 in drug resistant cells sensitized cells to cisplatin and doxorubicin.

Conclusions

Exo1 participated in mammalian non-homologous end joining and contributed to drug resistance in ovarian cancer.

Identification of hub genes and key pathways associated with the progression of gynecological cancer

Gynecological cancer is the leading cause of cancer mortality in women. However, the mechanisms underlying gynecological cancer progression have remained largely unclear. In the present study, 799 dysregulated genes were identified in ovarian serous cystadenocarcinoma (OV), 488 dysregulated genes in cervical squamous cell carcinoma and endocervical adenocarcinoma (CESC), and 621 dysregulated genes in uterine corpus endometrial carcinoma (UCEC). Bioinformatics analysis revealed that mRNA splicing and cell proliferation-associated biological processes served important roles in OV progression. Metabolism-associated biological processes played important roles in CESC progression, and protein phosphorylation and small GTPase-mediated signal transduction served important roles in UCEC progression. The present study also constructed OV, CESC and UCEC progression-associated protein-protein interaction networks to reveal the associations among these genes. Furthermore, Kaplan-Meier curve analysis showed that progression-related genes were associated with the duration of overall survival. Finally, NARS2 and TPT1 in OV, SMYD2, EGLN1, TNFRSF10D, FUT11, SYTL3, MMP8 and EREG in CESC, and SLC5A1, TXN, KDM4B, TXNDC11, HSDL2, COX16, MGAT4A, DAGLA, ELOVL7, THRB and PCOLCE2 in UCEC were identified as hub genes in cancer progression. Therefore, this study may assist in the identification of novel mechanisms underlying cancer progression and new biomarkers for gynecological cancer prognosis and therapy.

Ectopic expression of HSDL2 is related to cell proliferation and prognosis in breast cancer

Purpose

Human hydroxysteroid dehydrogenase-like 2 (HSDL2) is a characterized SDR gene that not only catalyses the oxidation and reduction of multiple substrates but also regulates different metabolic and signalling pathways. Accumulating evidences suggest that HSDL2 play an important role in cancer progression. However, the role of HSDL2 in breast cancer has not yet been determined. Thus, this study aims to explore the relevance of HSDL2 in breast cancer progression.

Patients and methods

The location of HSDL2 protein was detected in MDA-MB-231 breast cancer cells by using immunofluorescence (IF) staining. The expression level of HSDL2 was evaluated by immunohistochemical (IHC) staining in 119 breast cancer tissues and 40 normal breast tissues. Then, the correlations between the overexpression of HSDL2 and clinicopathological features of breast cancer patients were evaluated by using the chi-square test, and the survival rates were calculated by the Kaplan-Meier method. In addition, the role of HSDL2 in breast cancer proliferation was assessed by MTT and colony formation assays, and cell cycle distribution was detected by flow cytometry analysis and Western blot.

Results

IF staining and IHC analysis consistently showed that HSDL2 was predominantly expressed in the cytoplasm of breast cancer cells. The positive rate of HSDL2 protein was significantly higher in breast cancer tissues (87.4%, 104/119) than in adjacent normal breast tissues (25%, 10/40) (p<0.01). A high expression of HSDL2 protein was significantly associated with high histological grades, late clinical stages and low survival rates. Moreover, multivariate analysis indicated that HSDL2 protein was an independent prognostic factor in breast cancer patients. Studies in vitro showed that HSDL2 depletion reduced cell proliferation and induced cell cycle arrest in breast cancer.

Conclusion

In conclusion, this study indicated that HSDL2 plays a role in promoting the development of breast cancer. HSDL2 could be a valuable prognostic biomarker and a potential therapeutic target for patients with breast cancer.

Down-regulated HSDL2 expression suppresses cell proliferation and promotes apoptosis in papillary thyroid carcinoma

Papillary thyroid carcinoma (PTC) is the most common type of thyroid cancer. Hydroxysteroid dehydrogenase like 2 (HSDL2) can regulate lipid metabolism and take part in cell proliferation. The purpose of the present study was to explore functional role of HSDL2 gene in PTC. The expression of HSDL2 protein in PTC tissues was estimated using immunohistochemistry analysis (IHC). HSDL2 mRNA level was detected through quantitative real-time polymerase chain reaction (qRT-PCR). Effects of HSDL2 gene on cell proliferation and apoptosis were assessed using the shRNA method for both in vitro and in vivo experiments. Potential target genes of HSDL2 were determined via bioinformatics analyses and Western blotting. HSDL2 was up-regulated in PTC tissues and cell lines compared with the controls (all P<0.05). Inhibiting HSDL expression could suppress PTC cell proliferation and cycle, and promote apoptosis in vitro. In vivo, the knockdown of HSDL2 gene could significantly suppress tumor growth (all P<0.05). Furthermore, AKT3, NFATc2 and PPP3CA genes might be potential targets of HSDL2 in PTC. HSDL2 expression was increased in PTC tissues and cells, which could promote tumor progression in vitro and in vivo.

The peroxisome: an update on mysteries 2.0

Peroxisomes are key metabolic organelles, which contribute to cellular lipid metabolism, e.g. the β-oxidation of fatty acids and the synthesis of myelin sheath lipids, as well as cellular redox balance. Peroxisomal dysfunction has been linked to severe metabolic disorders in man, but peroxisomes are now also recognized as protective organelles with a wider significance in human health and potential impact on a large number of globally important human diseases such as neurodegeneration, obesity, cancer, and age-related disorders. Therefore, the interest in peroxisomes and their physiological functions has significantly increased in recent years. In this review, we intend to highlight recent discoveries, advancements and trends in peroxisome research, and present an update as well as a continuation of two former review articles addressing the unsolved mysteries of this astonishing organelle. We summarize novel findings on the biological functions of peroxisomes, their biogenesis, formation, membrane dynamics and division, as well as on peroxisome-organelle contacts and cooperation. Furthermore, novel peroxisomal proteins and machineries at the peroxisomal membrane are discussed. Finally, we address recent findings on the role of peroxisomes in the brain, in neurological disorders, and in the development of cancer.