CDK13 promotes lipid deposition and prostate cancer progression by stimulating NSUN5-mediated m5C modification of ACC1 mRNA.

Cyclin-dependent kinases (CDKs) regulate cell cycle progression and the transcription of a number of genes, including lipid metabolism-related genes, and aberrant lipid metabolism is involved in prostate carcinogenesis. Previous studies have shown that CDK13 expression is upregulated and fatty acid synthesis is increased in prostate cancer (PCa). However, the molecular mechanisms linking CDK13 upregulation and aberrant lipid metabolism in PCa cells remain largely unknown. Here, we showed that upregulation of CDK13 in PCa cells increases the fatty acyl chains and lipid classes, leading to lipid deposition in the cells, which is positively correlated with the expression of acetyl-CoA carboxylase (ACC1), the first rate-limiting enzyme in fatty acid synthesis. Gain- and loss-of-function studies showed that ACC1 mediates CDK13-induced lipid accumulation and PCa progression by enhancing lipid synthesis. Mechanistically, CDK13 interacts with RNA-methyltransferase NSUN5 to promote its phosphorylation at Ser327. In turn, phosphorylated NSUN5 catalyzes the m5C modification of ACC1 mRNA, and then the m5C-modified ACC1 mRNA binds to ALYREF to enhance its stability and nuclear export, thereby contributing to an increase in ACC1 expression and lipid deposition in PCa cells. Overall, our results disclose a novel function of CDK13 in regulating the ACC1 expression and identify a previously unrecognized CDK13/NSUN5/ACC1 pathway that mediates fatty acid synthesis and lipid accumulation in PCa cells, and targeting this newly identified pathway may be a novel therapeutic option for the treatment of PCa.

TREM2 as an independent predictor of poor prognosis promotes the migration via the PI3K/AKT axis in prostate cancer.

OBJECTIVE: Prostate adenocarcinoma (PRAD) is one of the most common cancers, with high morbidity and mortality. Triggering receptors expressed on myeloid cells 2 (TREM2) is upregulated in various malignancies, however its effect on PRAD remains unknown. This study aimed to investigate the prognostic value of TREM2 in PRAD. METHODS: PRAD samples were collected from The Cancer Genome Atlas (TCGA), the Gene Expression Omnibus (GEO), Oncomine, and the Human Protein Atlas (HPA) to analyze the differences in TREM2 expression between normal and tumor tissues. The influence of TREM2 on the clinicopathological characteristics and its prognostic value were evaluated using the Kaplan-Meier curve, Cox regression analysis, ROC (receiver operating characteristic) plot, and nomogram. Gene Ontology (GO), gene set enrichment analysis (GSEA), and protein-protein interaction (PPI) were conducted to screen biological functions and pathways. The relationship between TREM2 and tumor microenvironment (TME) characteristics was explored. The TREM2 expression in PRAD specimens and cell lines was assessed by immunohistochemistry staining and western blot. TREM2-specific siRNAs were used to evaluate the effects of TREM2 on cell function. RESULTS: TREM2 was upregulated and positively associated with poor clinicopathologic characteristics. Overexpression of TREM2 is an independent biomarker for the prognosis of PFI (progression-free interval). Moreover, TREM2 expression was positively correlated with various TME characteristics. Knockdown of TREM2 inhibited the migration of PRAD cell lines via the PI3K/AKT axis. CONCLUSION: High TREM2 expression may represent a novel diagnostic and prognostic biomarker and serve as a potential target gene for PRAD therapy.

PCGF6/MAX/KDM5D facilitates MAZ/CDK4 axis expression and pRCC progression by hypomethylation of the DNA promoter.

Polycomb group RING finger protein 6 (PCGF6) plays an important role as a regulator of transcription in a variety of cellular processes, including tumorigenesis. However, the function and expression of PCGF6 in papillary RCC (pRCC) remain unclear. In the present study, we found that PCGF6 expression was significantly elevated in pRCC tissues, and high expression of PCGF6 was associated with poor survival of patients with pRCC. The overexpression of PCGF6 promoted while depletion of PCGF6 depressed the proliferation of pRCC cells in vitro. Interestingly, myc-related zinc finger protein (MAZ), a downstream molecular of PCGF6, was upregulated in pRCC with hypomethylation promoter. Mechanically, PCGF6 promoted MAZ expression by interacting with MAX and KDM5D to form a complex, and MAX recruited PCGF6 and KDM5D to the CpG island of the MAZ promoter and facilitated H3K4 histone demethylation. Furthermore, CDK4 was a downstream molecule of MAZ that participated in PCGF6/MAZ-regulated progression of pRCC. These results indicated that the upregulation of PCGF6 facilitated MAZ/CDK4 axis expression and pRCC progression by hypomethylation of the MAZ promoter. The PCGF6/MAZ/CDK4 regulatory axis may be a potential target for the treatment of ccRCC.

SF3B4 promotes Twist1 expression and clear cell renal cell carcinoma progression by facilitating the export of KLF 16 mRNA from the nucleus to the cytoplasm.

Splicing factor 3B subunit 4 (SF3B4) plays important functional roles not only in pre-mRNA splicing, but also in the regulation of transcription, translation, and cell signaling, and its dysregulation contributes to various diseases including Nager syndrome and tumorigenesis. However, the role of SF3B4 and underlying mechanisms in clear cell renal cell carcinoma (ccRCC) remain obscure. In the present study, we found that the expression of SF3B4 was significantly elevated in ccRCC tissues and negatively correlated with the overall survival of ccRCC patients. Upregulation of SF3B4 promotes migration and invasion of ccRCC cells in vitro and in vivo. The promoting effect of SF3B4 on cell migration and invasion is mediated by Twist1, a key transcription factor to mediate EMT. Interestingly, SF3B4, a component of the pre-mRNA spliceosome, is able to promote KLF16 expression by facilitating the transport of KLF16 mRNA into the cytoplasm. Mechanistically, SF3B4 promotes the export of KLF16 mRNA from the nucleus to the cytoplasm and thus enhances KLF16 expression, and in turn elevated KLF16 directly binds to the Twist1 promoter to activate its transcription, leading to EMT and ccRCC progression. Our findings provide evidence that the SF3B4-KLF16-Twist1 axis plays important functional roles in the development and progression of ccRCC, and manipulating this pathway may be a novel therapeutic target for the treatment of ccRCC.

Disturbing NLRP3 acetylation and inflammasome assembly inhibits androgen receptor-promoted inflammatory responses and prostate cancer progression.

Chronic inflammation is one of the definite factors leading to the occurrence and development of tumors, including prostate cancer (PCa). The androgen receptor (AR) pathway is essential for PCa tumorigenesis and inflammatory response. However, little is known about the AR-regulated NACHT, LRR, and PYD domain-containing protein 3 (NLRP3) inflammasome pathway in human PCa. In this study, we explored the expression of inflammatory cytokine and AR in high-grade PCa and observed that NLRP3 inflammasome-associated genes were upregulated in high-grade PCa compared with that in low-grade PCa and benign prostatic hyperplasia and were associated with AR expression. In addition, we identified circAR-3-a circRNA derived from the AR gene-which is involved in the AR-regulated inflammatory response and cell proliferation by activating the NLRP3 inflammatory pathway. While circAR-3 overexpression promoted cell proliferation and the inflammatory response, its depletion induced opposite effects. Mechanistically, we noted that circAR-3 mediated the acetylation modification of NLRP3 by KAT2B and then promoted NLRP3 inflammasome complex subcellular distribution and assembly. Disturbing NLRP3 acetylation or blocking inflammasome assembly with an inhibitor suppressed the progression of PCa xenograft tumors. Our findings provide the first evidence that targeting NLRP3 acetylation or inflammasome assembly may be effective in inhibiting PCa progression.

The reasons and countermeasures of Bladder Rupture caused by Transurethral Clot Evacuation.

OBJECTIVE: Bladder rupture caused by transurethral clot evacuation is rare in clinic, but an emergency operation is indeed needed in the patient with bladder rupture. We analyzed the reasons of bladder rupture caused by transurethral clot evacuation and provided the countermeasures to guide clinical surgeon to prevent the iatrogenic damage of bladder. METHOD: We retrospectively reviewed the records of 287 patients in our hospital, who had bladder tamponade resulting from clots of blood for various reasons and underwent transurethral clot evacuation from January 2007 to January 2019. Six male cases, aged from 28 to 76 years (mean 56.67±17.76) had bladder rupture. Four patients whose bladder ruptured intraperitoneally were changed to open surgery to repair bladder and clear the remanent blood clots. Two patients with extraperitoneal bladder rupture and a small bladder crevasse underwent a conservative therapy. RESULTS: We observed that the incidence rate of bladder rupture was not associated with bladder tamponade and the age, but may be associated with gender, bladder paracentesis preoperative and urinary retention preoperative. All six cases were male.. They had different period of urinary retention before operation. No supra-pubis bladder paracentesis was made before operation. The bladder crevasses located in the triangle zone and posterior wall of bladder entirely, and the length of the bladder crevasses ranged from 3 to 7cm (mean 4.83cm). The bladder crevasses were all lengthways, and four cases were of' bladders ruptured intraperitoneally while another two presented an extraperitoneal bladder rupture. CONCLUSIONS: The reasons of bladder rupture caused by transurethral clot evacuation may be related to gender, bladder paracentesis preoperative and urinary retention preoperative. We should decide to use expectant treatment or open surgery immediately according to the extent of the rupture when bladder rupture occurs.

CDK13 upregulation-induced formation of the positive feedback loop among circCDK13, miR-212-5p/miR-449a and E2F5 contributes to prostate carcinogenesis.

BACKGROUND: Both E2F transcription factor and cyclin-dependent kinases (CDKs), which increase or decrease E2F activity by phosphorylating E2F or its partner, are involved in the control of cell proliferation, and some circRNAs and miRNAs regulate the expression of E2F and CDKs. However, little is known about whether dysregulation among E2Fs, CDKs, circRNAs and miRNAs occurs in human PCa. METHODS: The expression levels of CDK13 in PCa tissues and different cell lines were determined by quantitative real-time PCR and Western blot analysis. In vitro and in vivo assays were preformed to explore the biological effects of CDK13 in PCa cells. Co-immunoprecipitation anlysis coupled with mass spectrometry was used to identify E2F5 interaction with CDK13. A CRISPR-Cas9 complex was used to activate endogenous CDK13 and circCDK13 expression. Furthermore, the mechanism of circCDK13 was investigated by using loss-of-function and gain-of-function assays in vitro and in vivo. RESULTS: Here we show that CDK13 is significantly upregulated in human PCa tissues. CDK13 depletion and overexpression in PCa cells decrease and increase, respectively, cell proliferation, and the pro-proliferation effect of CDK13 is strengthened by its interaction with E2F5. Mechanistically, transcriptional activation of endogenous CDK13, but not the forced expression of CDK13 by its expression vector, remarkably promotes E2F5 protein expression by facilitating circCDK13 formation. Further, the upregulation of E2F5 enhances CDK13 transcription and promotes circCDK13 biogenesis, which in turn sponges miR-212-5p/449a and thus relieves their repression of the E2F5 expression, subsequently leading to the upregulation of E2F5 expression and PCa cell proliferation. CONCLUSIONS: These findings suggest that CDK13 upregulation-induced formation of the positive feedback loop among circCDK13, miR-212-5p/miR-449a and E2F5 is responsible for PCa development. Targeting this newly identified regulatory axis may provide therapeutic benefit against PCa progression and drug resistance.

Cholinergic α5 nicotinic receptor is involved in the proliferation and invasion of human prostate cancer cells.

Nicotinic acetylcholine receptor (nAChR) subunit α5 (α5­nAChR) is involved in tumor cell proliferation, inhibition of apoptosis, progression of metastasis, and induction of angiogenesis in certain solid tumors. However, the role of α5­nAChR in prostate cancer cell growth and metastasis is unclear. In the present study, the role of α5­nAChR in cell proliferation, migration, invasion and apoptosis was investigated by silencing the expression levels of α5­nAChR in the prostate cancer cell lines DU145 and PC3. A siRNA oligonucleotide targeting α5­nAChR was designed. The cell proliferation of DU145 and PC3 cell lines was analyzed by the Cell Counting Kit­8 (CCK­8) assay. Cell migratory and invasive activities were determined using wound healing and Transwell assays, respectively. Western blot analysis was used to quantify α5­nAChR, p­AKT and p­ERK1/2 levels in DU145 and PC3 cells. Knockdown of α5­nAChR was associated with decreased cell proliferation, migration, invasion and increased apoptosis. In addition, decreased phosphorylation levels of AKT and ERK1/2 were revealed following α5­nAChR knockdown in DU145 and PC3 cells compared with those observed in the scramble control samples. The expression levels of the apoptosis­related proteins were altered following silencing of α5­nAChR. In summary, the data indicated that α5­nAChR was involved in the proliferation and invasion of human prostate cancer cells.

miR-20b-5p, TGFBR2, and E2F1 Form a Regulatory Loop to Participate in Epithelial to Mesenchymal Transition in Prostate Cancer.

The transcription factor E2F1 regulates the expression of the miR-20b-5p precursor and is involved in epithelial-to-mesenchymal transition (EMT). Transforming growth factor-ß1 (TGF-ß1) induces EMT in prostate cancer (PCa) by binding to TGF-beta receptor 2 (TGFBR2) to activate TGF-ß signaling. However, the relationship between TGFBR2, E2F1, and miR-20b-5p in the modulation of EMT in PCa cells remains unknown. In this study, we found that the level of miR-20b-5p expression was significantly lower in PC3 and DU145 cells than that in prostate epithelial (RWPE-1) cells, and TGF-ß1 treatment further down-regulated miR-20b-5p expression in these two cell lines. Functional studies showed that miR-20b-5p suppressed TGF-ß1-induced migration and invasion of PC3 and DU145 cells by up-regulating E-cadherin and down-regulating vimentin, leading to TGF-ß1-induced inhibition of EMT. Using gain and loss of function experiments, it was shown that E2F1 mediated TGF-ß1 regulation of miR-20b-5p expression. Further, a luciferase activity assay showed that TGFBR2 was a direct target of miR-20b-5p in PCa cells. These results suggest that miR-20b-5p, TGFBR2, and E2F1 form a regulatory loop to modulate EMT induced by TGF-ß1. A novel regulatory mechanism underlying the miR-20b-5p/TGFBR2/E2F1 axis is involved in TGF-ß1-induced EMT of PCa cells, and miR-20b-5p may be a potential therapeutic target for PCa.

Dysregulation of p53-RBM25-mediated circAMOTL1L biogenesis contributes to prostate cancer progression through the circAMOTL1L-miR-193a-5p-Pcdha pathway.

p53, circRNAs and miRNAs are important components of the regulatory network that activates the EMT program in cancer metastasis. In prostate cancer (PCa), however, it has not been investigated whether and how p53 regulates EMT by circRNAs and miRNAs. Here we show that a Amotl1-derived circRNA, termed circAMOTL1L, is downregulated in human PCa, and that decreased circAMOTL1L facilitates PCa cell migration and invasion through downregulating E-cadherin and upregulating vimentin, thus leading to EMT and PCa progression. Mechanistically, we demonstrate that circAMOTL1L serves as a sponge for binding miR-193a-5p in PCa cells, relieving miR-193a-5p repression of Pcdha gene cluster (a subset of the cadherin superfamily members). Accordingly, dysregulation of the circAMOTL1L-miR-193a-5p-Pcdha8 regulatory pathway mediated by circAMOTL1L downregulation contributes to PCa growth in vivo. Further, we show that RBM25 binds directly to circAMOTL1L and induces its biogenesis, whereas p53 regulates EMT via direct activation of RBM25 gene. These findings have linked p53/RBM25-mediated circAMOTL1L-miR-193a-5p-Pcdha regulatory axis to EMT in metastatic progression of PCa. Targeting this newly identified regulatory axis provides a potential therapeutic strategy for aggressive PCa.

Silencing of miR-193a-5p increases the chemosensitivity of prostate cancer cells to docetaxel.

BACKGROUND: Docetaxel-based chemotherapy failure in advanced prostate carcinoma has partly been attributed to the resistance of prostate cancer (PC) cells to docetaxel-induced apoptosis. Hence, there is an urgent need to identify mechanisms of docetaxel chemoresistance and to develop new combination therapies. METHODS: miR-193a-5p level was evaluated by qPCR in prostate tissues and cell lines, and its expression in the tissues was also examined by in situ hybridization. PC cell line (PC3 cell) was transfected with miR-193a-5p mimic or its inhibitor, and then cell apoptosis and the expression of its downstream genes Bach2 and HO-1 were detected by TUNEL staining and Western blotting. Luciferase reporter assay was used to detect the effect of miR-193a-5p and Bach2 on HO-1 expression. Xenograft animal model was used to test the effect of miR-193a-5p and docetaxel on PC3 xenograft growth. RESULTS: miR-193a-5p was upregulated in PC tissues and PC cell lines, with significant suppression of PC3 cell apoptosis induced by oxidative stress. Mechanistically, miR-193a-5p suppressed the expression of Bach2, a repressor of the HO-1 gene, by directly targeting the Bach2 mRNA 3'-UTR. Docetaxel treatment modestly decreased Bach2 expression and increased HO-1 level in PC3 cells, whereas a modest increase of HO-1 facilitated docetaxel-induced apoptosis. Notably, docetaxel-induced miR-193a-5p upregulation, which in turn inhibits Bach2 expression and thus relieves Bach2 repression of HO-1 expression, partly counteracted docetaxel-induced apoptosis, as evidenced by the increased Bcl-2 and decreased Bax expression. Accordingly, silencing of miR-193a-5p enhanced sensitization of PC3 cells to docetaxel-induced apoptosis. Finally, depletion of miR-193a-5p significantly reduced PC xenograft growth in vivo. CONCLUSIONS: Silencing of miR-193a-5p or blockade of the miR-193a-5p-Bach2-HO-1 pathway may be a novel therapeutic approach for castration-resistant PC.

[L-carnitine: safe and effective for asthenozoospermia].

OBJECTIVE: One of the important reasons for male infertility is asthenozoospermia, for which there is no specific cure for the time being. The authors explored the clinical effect of L-carnitine for infertile males with asthenozoospermia. METHODS: A total of 135 patients with asthenozoospermia were randomly divided into Groups A (n = 68) and B (n = 67), the former treated with L-carnitine (2 g/d) and vitamin E, while the latter with vitamin E only, both for 3 months. All the patients received semen analyses before and after the treatment, and were observed for adverse effects. The pregnancy rates of their wives were recorded. RESULTS: Group A showed a significantly increased percentage of forward motile sperm after the treatment (45.4% +/- 11.1%) as compared with pretreatment (28.6% +/- 9.2%) (P < 0.01), but no statistically significant differences were found in sperm density and the percentage of the sperm of normal morphology (P > 0.05). The rate of pregnancy was significantly higher in Group A (31.1%) than in B (3.8%) after the treatment (P < 0.01). No adverse events were found during the treatment. CONCLUSION: L-carnitine, capable of significantly improving sperm motility and raising the rate of pregnancy, is a safe and effective therapeutic option for asthenozoospermia.

[The application of tunica vaginalis flap in urethral repair].

OBJECTIVE: To investigate the application of tunica vaginalis flap in repairing the deformity of urethra and urethral fistulas. METHODS: Tunica vaginalis flap from the scrotum were used to wrap the reconstructed urethra in the 38 cases of hypospadias urethroplasty and urethral fistulas repair from 2002. RESULTS: All of cases were followed up for six months to one year. There was a fistula reoccurred after epispadias fistula repair, the repair was successful in other patients. There was no recurrent fistulas or urethral strictures. Penile cosmesis was excellent and erected well. CONCLUSIONS: The application of tunica vaginalis flap in urethral repair can raise achievement ratio and reduce the incidence of urethral fistulas. The flap is ease to mobilize with no harmful effects on the testicles.

[Correction of pediatric concealed penis by using a modified Devine' s technique].

OBJECTIVE: To discuss the diagnosis of pediatric concealed penis and evaluate the results after the correction of the pediatric concealed penis. METHODS: Twenty patients with pediatric concealed penis were treated by using a modified Devine's technique. RESULTS: The appearance with a straightening penile was achieved in all of the patients. All of the patients recovered well after the operation without any complications. CONCLUSIONS: The modified Devine' s technique could be a safe and effective method for the correction of the pediatric concealed penis with satisfactory outcome.