Inhibited Bladder Cancer Cell Proliferation Research Articles

LINC00461 promotes bladder cancer cells EMT through miR-518b/HNRNPUL1 axis

Bladder cancer (BC) is a prevalent type of tumor in the urinary system, and it has been discovered that long non‐coding RNA (lncRNA) plays a significant role in its occurrence and development. However, thus far, no reports have been published on the involvement of LINC00461 in BC. Here, we found that LINC00461 levels were upregulated in BC tissues and cell lines. Besides, knockdown of LINC00461 inhibited BC cell proliferation, migration, invasion through epithelial-mesenchymal transition (EMT), and slowed down tumor growth in vivo. Moreover, we found that LINC00461 regulated HNRNPUL1 expression through miR-518b sponge activity, and the miR-518 inhibitor could reverse the inhibitory effects of LINC00461 knockdown on BC cell proliferation, migration, and EMT. Our results suggest that LINC00461 may serve as a potential biomarker and therapeutic target for BC.

PC4 promotes bladder cancer progression and stemness by directly interacting with Sp1 to transcriptionally activate the Wnt5a/β-catenin pathway

Bladder cancer is a common malignancy with a poor prognosis worldwide. Positive cofactor 4 (PC4) is widely reported to promote malignant phenotypes in various tumors. Nonetheless, the biological function and mechanism of PC4 in bladder cancer remain unclear. Here, for the first time, we report that PC4 is elevated in bladder cancer and is associated with patient survival. Moreover, PC4 deficiency obviously inhibited bladder cancer cell proliferation and metastasis by reducing the expression of genes related to cancer stemness (CD44, CD47, KLF4 and c-Myc). Through RNA-seq and experimental verification, we found that activation of the Wnt5a/β-catenin pathway is involved in the malignant function of PC4. Mechanistically, PC4 directly interacts with Sp1 to promote Wnt5a transcription. Thus, our study furthers our understanding of the role of PC4 in cancer stemness regulation and provides a promising strategy for bladder cancer therapy.

SRT1720 inhibits bladder cancer cell progression by impairing autophagic flux

Bladder cancer (BC) is the most common cancer of the urinary tract, with poor survival, high recurrence rates, and lacking of targeted drugs. In this study, we constructed a library to screen compounds inhibiting bladder cancer cells growth. Among them, SRT1720 was identified to inhibit bladder cancer cell proliferation in vitro and in vivo. SRT1720 treatment also suppressed bladder cancer cells migration, invasion and induced apoptosis. Mechanism studies shown that SRT1720 promoted autophagosomes accumulation by inducing early-stage autophagy but disturbed the late-stage of autophagy by blocking fusion of autophagosomes and lysosomes. SRT1720 appears to induce autophagy related proteins expression and alter autophagy-related proteins acetylation to impede the autophagy flux. LAMP2, an important lysosomal associated membrane protein, may mediate SRT1720-inhibited autophagy flux as SRT1720 treatment significantly deacetylated LAMP2 which may influence its activity. Taken together, our results demonstrated that SRT1720 mediated apoptosis and autophagy flux inhibition may be a novel therapeutic strategy for bladder cancer treatment.

Hesperetin Inhibits Bladder Cancer Cell Proliferation and Promotes Apoptosis and Cycle Arrest by PI3K/AKT/FoxO3a and ER Stress-mitochondria Pathways.

Hesperetin (HSE) is a natural flavonoid derived from the hydrolysis of Hesperidin, which is mainly found in traditional natural Chinese herbs, such as Chenpi and Hovenia caryophyllus. HSE displays anti-inflammatory and antioxidant activities. However, its potential mechanism of action on bladder cancer (BLCA) remains unknown. The aim of this study was to investigate the potential mechanism of action of HSE on BLCA cells. Network pharmacology analysis was used to construct a composite target network, combined with Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis to identify HSE-induced cell death patterns and signaling pathway alterations. Cytotoxicity evaluation was determined by CCK-8 assay. A clone formation assay was performed to assess cell proliferative capacity. Scratch and Transwell assays were performed to evaluate cell migration and invasion ability. Hoechst 33342 staining was visualized to observe morphological features of apoptosis. Apoptosis, cycle distribution, reactive oxygen species (ROS) generation, and mitochondrial membrane potential (MMP) changes were examined by flow cytometry. Western blot analysis was performed to analyze the expression of key proteins associated with cell proliferation, apoptosis, cycle block, PI3K/AKT/FoxO3a and endoplasmic reticulum (ER) stress-mitochondrial pathways. Network pharmacology analysis was performed to identify 155 potential candidate targets of HSE-BLCA, and further topological analysis was performed to obtain 34 hub-gene. Enrichment analysis yielded patterns of death and key pathways, revealing that the anti-BLCA effect of HSE may be related to the positive regulation of PI3K/AKT/FoxO3a and ER stress-mitochondrial pathways. in vitro results showed that HSE blocked cell proliferation, migration, and invasion in a concentration-dependent manner and triggered apoptosis, G0/G1 phase blockade, ROS production, and MMP depolarization. In addition, Western blot results showed that HSE downregulated phosphorylated (p)-3-phosphoinositide-dependent kinase-1 (PI3K), phosphorylated (p)-AKT serine/threonine kinase 1 (AKT), phosphorylated (p)-Forkhead box O 3a (FoxO3a), anti-apoptotic proteins, proliferation-associated proteins, and cell cycle promoters, whereas the levels of proteins related to the expression of cell cycle regulators, pro-apoptotic proteins, and ER stress-mitochondrial pathway were up-regulated in BLCA cells by the intervention of HSE. PI3K agonist (YS-49) and ER stress inhibitor (4-PBA) partially or completely reversed HSE-mediated proliferation, apoptosis, and cycle blockade in BLCA cells. The anticancer effects of HSE in BLCA may be attributed to its coordination of actions, inhibiting cell proliferation, migration, and invasion, inducing apoptosis, G0/G1 phase arrest, generating reactive oxygen species, causing MMP loss, and engaging the caspase protein family. These actions are likely mediated through the PI3K/AKT/FoxO3a and ER stress-mitochondrial pathways. Thus, our findings suggest that HSE is a promising novel therapeutic candidate for the prevention and treatment of BLCA.

USP5 facilitates bladder cancer progression by stabilizing the c-Jun protein

BackgroundBladder cancer is the second most common genitourinary malignancy worldwide. The death rate of bladder cancer has increased every year. However, the molecular mechanism of bladder cancer is not sufficiently studied. Deubiquitinating enzymes (DUBs) play an important role in carcinogenesis. Several studies have demonstrated that USP5 associated with malignancy and pathological progression in hepatocellular carcinoma, colorectal and non-small cell lung cancer. However, the role of USP5 in bladder cancer need to be explored.MethodsThe USP5 expression was analysed using the web server GEPIA. To explore USP5 function in bladder cancer, we constructed USP5-knockout cell lines in T24 cells. A FLAG-USP5 (WT USP5) plasmid and a plasmid FLAG-USP5 C335A (catalytic-inactive mutant) used to overexpress USP5 in EJ cells. CCK8, colony formation, transwell and scratch assays were used to assess cell viability, proliferation and migration. RNA sequencing (RNA-seq) and dual-luciferase reporter assays were performed to screen the pathway. Coimmunoprecipitation and immunofluorescence were used to explore the interaction between USP5 and c-Jun. Cycloheximide (CHX) chase assays were performed to establish the effect of USP5 on c-Jun stability. Xenograft mouse model was used to study the role of USP5 in bladder cancer.ResultsUSP5 expression is increased in bladder cancer patients. Genetic ablation of USP5 markedly inhibited bladder cancer cell proliferation, viability, and migration both in vitro and in vivo. RNA-seq and luciferase pathway screening showed that USP5 activated JNK signalling, and we identified the interaction between USP5 and c-Jun. USP5 was found to activate c-Jun by inhibiting its ubiquitination.ConclusionsOur results show that high USP5 expression promotes bladder cancer progression by stabilizing c-Jun and that USP5 is a potential therapeutic target in bladder cancer.

Establishment of a SUMO pathway related gene signature for predicting prognosis, chemotherapy response and investigating the role of EGR2 in bladder cancer.

Background: Bladder cancer is a prevalent malignancy with significant clinical implications. Small Ubiquitin-like Modifier (SUMO) pathway related genes (SPRG) have been implicated in the development and progression of cancer. Methods: In this study, we conducted a comprehensive analysis of SPRG in bladder cancer. We analyzed gene expression and prognostic value of SPRG and developed a SPRG signature (SPRGS) prognostic model based on four genes (HDAC4, TRIM27, EGR2, and UBE2I) in bladder cancer. Furthermore, we investigated the relationship between SPRGS and genomic alterations, tumor microenvironment, chemotherapy response, and immunotherapy. Additionally, we identified EGR2 as a key SPRG in bladder cancer. The expression of EGR2 in bladder cancer was detected by immunohistochemistry, and the cell function experiment clarified the effect of knocking down EGR2 on the proliferation, invasion, and migration of bladder cancer cells. Results: Our findings suggest that SPRGS hold promise as prognostic markers and predictive biomarkers for chemotherapy response and immunotherapy efficacy in bladder cancer. The SPRGS prognostic model exhibited high predictive accuracy for bladder cancer patient survival. We also observed correlations between SPRG and genomic alterations, tumor microenvironment, and response to chemotherapy. Immunohistochemical results showed that EGR2 was highly expressed in bladder cancer tissues, and its overexpression was associated with poor prognosis. Knockdown of EGR2 inhibited bladder cancer cell proliferation, invasion, and migration. Conclusion: This study provides valuable insights into the landscape of SPRGS in bladder cancer and their potential implications for personalized treatment strategies. The identification of EGR2 as a key SPRG and its functional impact on bladder cancer cells further highlights its significance in bladder cancer development and progression. Overall, SPRGS may serve as important prognostic markers and predictive biomarkers for bladder cancer patients, guiding treatment decisions and improving patient outcomes.

Puerarin modulation of CENPA affects downstream PLK1 and CCNB1 expression to inhibit bladder cancer cell proliferation

Puerarin modulation of CENPA affects downstream PLK1 and CCNB1 expression to inhibit bladder cancer cell proliferation

Apatinib Inhibits Bladder Cancer through Suppression of the VEGFR2- PI3K-AKT Signaling Pathway as Revealed by Network Pharmacology and in vitro Experimental Verification.

This study aimed to evaluate the underlying pharmacological mechanisms of Apatinib anti-bladder cancer via network pharmacology and experimental verification. Network pharmacology was used to screen the possible signaling pathways of Apatinib in bladder cancer, and the most likely pathway was selected for in vitro validation. CCK-8 and colony formation assay were used to detect the effect of Apatinib on the proliferation of bladder cancer cells. Hoechst staining and flow cytometry detected apoptosis of bladder cancer cells induced by Apatinib. Western blot was performed to distinguish the effect of Apatinib on the expression levels of key targets. Apatinib can affect many signaling pathways and the correlation of the PI3K-AKT signaling pathway was the greatest. In vitro experiments showed that Apatinib could inhibit bladder cancer cell proliferation, induce apoptosis, and up-regulate the expression of apoptosisrelated proteins Cleaved-PARP and down-regulate the expression of Bcl-2. Furthermore, Apatinib could decrease the protein expression of VEGFR2, P-VEGFR2, P-PI3K and P-AKT. Apatinib could promote apoptosis of bladder cancer cells by inhibiting the VEGFR2- PI3K-AKT signaling pathway.

Senescence-related gene c-Myc affects bladder cancer cell senescence by interacting with HSP90B1 to regulate cisplatin sensitivity.

Patients with advanced bladder cancer gradually become less sensitive to chemotherapeutic agents, leading to tumor recurrence. Initiating the senescence program in solid tumors may be an important means of improving short-term drug sensitivity. The important role of c-Myc in bladder cancer cell senescence was determined using bioinformatics methods. The response to cisplatin chemotherapy in bladder cancer sample was analyzed according to the Genomics of Drug Sensitivity in Cancer database. Cell Counting Kit-8 assay, clone formation assay, and senescence-associated β-galactosidase staining were used to assess bladder cancer cell growth, senescence, and sensitivity to cisplatin, respectively. Western blot and immunoprecipitation were performed to understand the regulation of p21 by c-Myc/HSP90B1. Bioinformatic analysis showed that c-Myc, a cellular senescence gene, was significantly associated with bladder cancer prognosis and sensitivity to cisplatin chemotherapy. c-Myc and HSP90B1 expression were highly correlated in bladder cancer. Reducing the level of c-Myc significantly inhibited bladder cancer cell proliferation, promoted cellular senescence, and enhanced cisplatin chemosensitivity. Immunoprecipitation assays confirmed that HSP90B1 interacted with c-Myc. Western blot analysis showed that reducing the level of HSP90B1 could redeem the p21 overexpression caused by c-Myc overexpression. Further studies showed that reducing HSP90B1 expression could alleviate the rapid growth and accelerate cellular senescence of bladder cancer cells caused by c-Myc overexpression, and that reducing HSP90B1 levels could also improve cisplatin sensitivity in bladder cancer cells. HSP90B1/c-Myc interaction regulates the p21 signaling pathway, which affects cisplatin chemosensitivity by modulating bladder cancer cell senescence.

TROP2 translation mediated by dual m6A/m7G RNA modifications promotes bladder cancer development

RNA modifications, including adenine methylation (m6A) of mRNA and guanine methylation (m7G) of tRNA, are crucial for the biological function of RNA. However, the mechanism underlying the translation of specific genes synergistically mediated by dual m6A/m7G RNA modifications in bladder cancer (BCa) remains unclear. We demonstrated that m6A methyltransferase METTL3-mediated programmable m6A modification of oncogene trophoblast cell surface protein 2 (TROP2) mRNA promoted its translation during malignant transformation of bladder epithelial cells. m7G methyltransferase METTL1 enhanced TROP2 translation by mediating m7G modification of certain tRNAs. TROP2 protein inhibition decreased the proliferation and invasion of BCa cells in vitro and in vivo. Moreover, synergistical knockout of METTL3/METTL1 inhibited BCa cell proliferation, migration, and invasion; however, TROP2 overexpression partially abrogated its effect. Furthermore, TROP2 expression was significantly positively correlated with the expression levels of METTL3 and METTL1 in BCa patients. Overall, our results revealed that METTL3/METTL1-mediated dual m6A/m7G RNA modifications enhanced TROP2 translation and promoted BCa development, indicating a novel RNA epigenetic mechanism in BCa.

Network-based Pharmacology and In vitro Validation Reveal that Galangin Induces Apoptosis in Bladder Cancer Cells by Promoting the P53 Signaling Pathway.

Galangin is one of the flavonoids in Alpinia officinarum. It has various anti-tumor activities, but its anti-bladder cancer effect is unclear. To investigate the mechanism of action of galangin against bladder cancer using a network pharmacology approach. The TCM Systematic Pharmacology Database and Analysis Platform (TCMSP), SwissTargetPrediction database, and the Targetnet database were used to predict the targets of action of galangin. Bladder cancer-related targets were obtained through the GeneCards database. The intersection of the two was taken as the target of galangin's action against bladder cancer. The intersecting targets were screened for core targets using the STRING database and Cytoscape 3.9.0 software to build a protein-protein interaction (PPI) network of targets. The core targets were subjected to gene ontology (GO) functional annotation and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis using the online annotation and visual integration analysis tool DAVIDBioinformaticsResources (2021Update). A drug-disease-target-pathway network was constructed using Cytoscape 3.9.0 software. The antibladder cancer effect of galangin was observed by cell proliferation, and plate cloning assay; apoptosis of bladder cancer cells induced by galangin was detected by Hoechst33342 staining and flow cytometry; protein immunoblotting (Western-blot) was used to detect the effect of galangin on apoptosis-related proteins Bax, Bcl-2, Cleaved-PARP, p53 signaling pathway p53 and cytc. A total of 115 genes were obtained from galangin against bladder cancer, and 16 core targets were screened. The kEGG pathway enrichment analysis included Pathways in cancer, PI3K-AKT signaling pathway, p53 signaling pathway, etc. In vitro experiments showed that galangin could inhibit bladder cancer cell proliferation, induce apoptosis, upregulate the expression of apoptosis-related proteins Bax and Cleaved-PARP and downregulate the expression of Bcl-2; meanwhile, galangin could promote the upregulation of the expression of p53 and cytc proteins by activating the p53 signaling pathway. Galangin induced apoptosis in bladder cancer cells by activating the p53 signaling pathway.

SH3BP5-AS1/IGF2BP2/VDAC2 Axis Promotes the Apoptosis and Ferroptosis of Bladder Cancer Cells.

Bladder cancer (BC) is the most common malignant tumor in the urinary system with a high incidence, imposing a burden on the healthcare system worldwide. The participation of long non-coding RNAs (lncRNAs) in BC has attracted increasing attention. The aim in the current study was to explore the potential mechanism involving SH3BP5-AS1 in modulating BC cell proliferation, apoptosis and ferroptosis. qPCR and WB analysis measured the expression of RNAs and proteins. Functional and mechanism experiments were performed to investigate RNA impacts on cell proliferation, apoptosis and ferroptosis, and explore the correlation between RNA and protein expression. SH3BP5-AS1 was down-regulated in BC cells, and SH3BP5-AS1 overexpression could inhibit BC cell proliferation but facilitate the cell apoptosis. SH3BP5-AS1 was also found to facilitate the ferroptosis of BC cells. Additionally, SH3BP5-AS1 was confirmed to recruit IGF2BP2 to regulate VDAC2 expression in the m6A-dependent manner. VDAC2 was detected to be down-regulated in BC cells and was verified to inhibit BC cell growth. Moreover, it was indicated from rescue assays that SH3BP5-AS1 could modulate VDAC2 expression to promote the ferroptosis of BC cells. SH3BP5-AS1 could affect BC cell proliferation, apoptosis and ferroptosis via IGF2BP2/VDAC2, providing a novel molecular perspective for understanding BC.

SNHG18 inhibits bladder cancer cell proliferation by increasing p21 transcription through destabilizing c-Myc protein

BackgroundLong non-coding RNAs (lncRNAs) have been confirmed to play important roles in various cancers including bladder cancer (BC). The precise expression pattern of lncRNA small nucleolar RNA host gene 18 (SNHG18) in BC and its mechanisms of action have not been fully explored.Materials and methodsThe expression of SNHG18 was evaluated by RT-qPCR in bladder cancer clinical samples and human bladder cancer cell lines, and stable cell lines overexpressing SNHG18 were constructed. The effect of SNHG18 on the proliferation of bladder cancer cells was detected by soft agar colony formation test, ATP activity test and subcutaneous tumorigenesis model in nude mice. The specific mechanism of SNHG18 inhibition of bladder cancer proliferation was studied by flow cytometry, western blotting, dual luciferase reporter gene assay and protein degradation assay.ResultsWe found that SNHG18 is significantly downregulated in BC tissues and cell lines. Kaplan–Meier analysis showed that SNHG18 expression is positively correlated with survival in BC patients. Ectopic overexpression of SNHG18 significantly inhibited the proliferation of BC cells in vitro and in vivo. Further mechanistic investigations demonstrated that SNHG18 inhibited c-Myc expression by modulating the ubiquitination-proteasome pathway and that c-Myc is the critical transcription factor that mediates SNHG18 inhibition of BC growth by directly binding to the p21 promoter, which was attributed with significant p21 accumulation.ConclusionsSNHG18 promotes the transcription and expression of p21 by inhibiting c-Myc expression, leading to G0-G1 arrest and inhibiting the proliferation of bladder cancer cells. These findings highlight a novel cell cycle regulatory mechanism involving the SNHG18/c-Myc/p21 pathway in BC pathogenesis and could potentially lead to new lncRNA-based diagnostics and/or therapeutics for BC.

Nitidine chloride regulates cell function of bladder cancer in vitro through downregulating Lymphocyte antigen 75.

Nitidine chloride (NC) is effective on cancer in many tumors, but its effect on bladder cancer (BC) is unknown. We conducted cell function experiments to verify the antineoplastic effect of NC on BC cell lines (5637, T24, and UM-UC-3) in vitro. Then, mRNAs of NC-treated and NC-untreated BC cells were extracted for mRNA sequencing. Differentially expressed genes (DEGs), expression analysis, and drug molecular docking were conducted to discover the target gene of NC. Finally, functional enrichment was analyzed to explore the underlying mechanisms. NC dramatically inhibited proliferation, migration, and invasion, and it induced apoptosis and arrested the S and G2/M phases of BC cell lines. Lymphocyte antigen 75 (LY75) appeared to be the target of NC. LY75 was highly expressed and had the ability to distinguish BC tissue from non-cancerous tissue. Then, drug molecular docking confirmed the targeting relationship between NC and LY75. Gene enrichment analysis showed that the downregulated genes, after being treated with NC, were mainly enriched in pathways relevant to cell pathophysiological processes. NC inhibits BC cell proliferation, migration, and invasion, induces apoptosis, and arrests cell cycles by downregulating the expression of LY75. This study provides molecular and theoretical bases for NC treatment of BC.

Depletion of PSMD14 suppresses bladder cancer proliferation by regulating GPX4.

The aim of this study was to investigate the role of deubiquitinase (DUB) 26S proteasome non-ATPase regulatory subunit 14 (PSMD14) in patients with bladder cancer. From 2016 to 2018, 181 patients diagnosed with primary bladder cancer at the Affiliated Hospital of Qingdao University were recruited. The expression of PSMD14 in bladder cancer tissues was tested by immunochemistry. The association between PSMD14 expression and clinical and pathological data and outcomes of bladder cancer patients was determined. Overexpression and knockdown cells were constructed to evaluate the effects of PSMD14 on proliferation of bladder cancer cells. Our results showed that PSMD14 was significantly overexpressed in bladder cancer tissues compared to adjacent non-tumor tissues (76.24% vs 23.76%, P = 0.02). The expression of PSMD14 was significantly higher in patients with larger tumor diameters (85.14% vs 70.09%, P = 0.019) and patients with a family history of cancer (92.16% vs 70.00%, P = 0.002). Patients with high expression of PSMD14 had poor disease-free survival (DFS) (HR = 2.89, 95% CI [1.247-6.711], P = 0.013). Gain and loss of function experiments demonstrated that PSMD14 deficiency inhibited bladder cancer cell proliferation. Additionally, depletion of PSMD14 suppressed bladder cancer cell growth via down-regulation of GPX4, and the promotion of PSMD14-induced cell growth was observably reversed by the GPX4 inhibitor RSL3. We determined that PSMD14 is highly expressed in bladder cancer tissues, and that PSMD14 expression correlated with poor disease-free survival. Depletion of PSMD14 could inhibit the proliferation of bladder cancer cells through the downregulation of GPX4. Therefore, PSMD14 may be an effective target for the treatment of bladder cancer.

Antibladder Cancer Effects of Excavatolide C by Inducing Oxidative Stress, Apoptosis, and DNA Damage In Vitro.

Excavatolide C (EXCC) is a bioactive compound derived from the gorgonian octocoral Briareum excavatum, and its anticancer effects are rarely addressed, particularly for bladder cancer. This investigation aimed to explore the potential impacts of EXCC on inhibiting the proliferation of three kinds of bladder cancer cells (5637, BFTC905, and T24). EXCC inhibits bladder cancer cell proliferation based on 48 h ATP assay. This antiproliferation function is validated to be oxidative stress dependent. Cellular and mitochondrial oxidative stresses were upregulated by EXCC, accompanied by depleting glutathione and mitochondrial membrane potential. These antiproliferation and oxidative stress events were suppressed by N-acetylcysteine (NAC), indicating that EXCC has an oxidative stress-regulating function for antiproliferation of bladder cancer cells. Oxidative stress-related responses such as apoptosis, caspase activation, and DNA damage were upregulated by EXCC and reverted by NAC. Taken together, the antiproliferation function of EXCC provides a potential treatment against bladder cancer cells via oxidative stress modulation.

Lamin B2 contributes to the proliferation of bladder cancer cells via activating the expression of cell division cycle‑associated protein 3.

Bladder cancer is the most common malignant tumor of the urinary system, and in China it is first among urogenital system tumors. More therapeutic targets are still urgently required to combat this disease. Lamin B2 (LMNB2) is a type of nuclear lamina filament protein, which is involved in multiple cellular processes, and known as an oncogene affecting the progression of multiple types of cancers. Although the multiple effects of LMNB2 on cancer progression have been elucidated, its possible role in bladder cancer remains unclear. In the present study, it was determined that LMNB2 expression was upregulated in human bladder cancer tissues, and its expression was correlated with the prognosis and the clinical features, including tumor stage (P=0.001) and recurrence (P=0.006) of patients with bladder cancer. In addition, it was further revealed that LMNB2 depletion inhibited bladder cancer cell proliferation, stimulated cell cycle arrest and apoptosis in vitro, and suppressed tumor growth of bladder cancer cells in mice. Furthermore, the present data revealed that LMNB2 promoted the proliferation of bladder cancer cells via transcriptional activation of CDCA3 expression. Therefore, the role of LMNB2 in bladder cancer progression was demonstrated, and may serve as a promising therapeutic target for bladder cancer treatment.

Fine particulate matter induces METTL3-mediated m6A modification of BIRC5 mRNA in bladder cancer

Long-term exposure to fine particulate matter (PM2.5) is reportedly related to a variety of cancers including bladder cancer. However, little is known about the biological mechanism underlying this association. In the present study, PM2.5 exposure was significantly associated with increased levels of m6A modification in bladder cancer patients and bladder cells. METTL3 expression was aberrantly upregulated after PM2.5 exposure, and METTL3 was involved in PM2.5-induced m6A methylation. Higher METTL3 expression was observed in bladder cancer tissues and METTL3 knockdown dramatically inhibited bladder cancer cell proliferation, colony formation, migration and invasion, inducing apoptosis and disrupting the cell cycle. Mechanistically, PM2.5 enhanced the expression of METTL3 by inducing the promoter hypomethylation of its promoter and increasing the binding affinity of the transcription factor HIF1A. BIRC5 was identified as the target of METTL3 through m6A sequencing (m6A-Seq) and KEGG analysis. The methylated BIRC5 transcript was subsequently recognized by IGF2BP3, which increased its mRNA stability. In particular, PM2.5 exposure promoted the m6A modification of BIRC5 and its recognition by IGF2BP3. In addition, BIRC5 was involved in bladder cancer proliferation and metastasis, as well as VEGFA-regulated angiogenesis. This comprehensive study revealed that PM2.5 exposure exerts epigenetic regulatory effects on bladder cancer via the HIF1A/METTL3/IGF2BP3/BIRC5/VEGFA network.

MiR-148a-3p inhibits the proliferation and migration of bladder cancer via regulating the expression of ROCK-1.

PurposeTo investigate the mechanism of miR-148a-3p regulating the proliferation and migration of bladder tumor cells.Materials and MethodsWe conducted a preliminary study to detect the relative expression of miR-148a-3p in bladder cancer and para-cancerous tissue samples. Three bladder tumor cell lines, T24, 5,637 and UM-UC-3, were selected. The expression levels of miR-148a-3p were artificially regulated with miR-148a-3p mimics and the miR-148a-3p inhibitor. The relative expression levels of miR-148a-3p in the samples of each cell line were determined. Cell Counting Kit-8 (CCK-8) was used to detect cell proliferation, while the effect of the miR-148a-3p mimics and inhibitor on tumor cell migration was detected by wound healing assay. Flow cytometry assay was carried out to explore the effect of miR-148a-3p on cell apoptosis. Dual-luciferase reporter assay was performed in order to verify miR-148a-3p’s target gene. The expressions of ROCK-1 and Bcl-2 were analyzed by western blot.ResultsThe relative expression of miR-148a-3p in tumor and adjacent tissues was assessed with qRT-PCR (P < 0.05) and found to be significantly lower in the tumor tissues than the adjacent tissues. The data obtained from the CCK-8 and wound healing assay showed that intracellular transfection of miR-148a-3p mimics could inhibit cell proliferation and migration, while the miR-148a-3p inhibitor promoted them. Overexpression of miR-148a-3p promoted cell apoptosis in the T24 and 5,637 cell lines. The dual-luciferase reporter assay verified that ROCK-1 is a direct target of miR-148a-3p. Western blot showed that miR-148a-3p overexpression downregulated the expression of ROCK-1 and Bcl-2, while miR-148a-3p knockdown upregulated the expression of ROCK-1 and Bcl-2.ConclusionsWe confirmed that miR-148a-3p was significantly decreased in bladder cancer cells. miR-148a-3p overexpression inhibited bladder cancer cell proliferation and migration, whereas miR-148a-3p knockdown promoted bladder cancer cell proliferation and migration. Moreover, we found that ROCK-1 was a downstream target of miR-148a-3p. We also found that miR-148a-3p induced cell apoptosis by regulating the expression of Bcl-2. However, the deeper mechanism of this regulatory relationship needs further study.

Adeno-associated virus-delivered alpha synuclein inhibits bladder cancer growth via the p53/p21 signaling pathway.

Alpha-synuclein (α-syn), encoded by the SNCA gene, is a major participant in the pathophysiology of Parkinson's disease (PD). Its functions have been reported to be related to apoptosis induction, the elevation of oxidative stress, mitochondrial homeostasis, cell-cycle aberrations, and DNA-related interactions. Evidence obtained in recent studies suggests a possible link between α-syn and cancer development. Bladder cancer (BCa) is the second most common genitourinary malignancy, with the population of survivors of BCa increasing worldwide. In this study, we show that α-syn expression was significantly downregulated in BCa. In vitro and in vivo experiments showed that α-syn could significantly inhibit BCa cell proliferation by arresting the cell cycle in the S phase via upregulation of p53 expression mediated by DNA damages. Further experiments showed that overexpression of α-syn delivered by adeno-associated viruses (AAVs) exerted inhibitory effects on the growth of BCa tumors. These findings indicate that αα-syn is a functional tumor suppressor that can inhibit the proliferation of BCa cells by activating the p53/p21 signaling pathway. Our present study provides insights into the roles of α-syn in BCa and suggests that α-syn may be a novel therapeutic target for the treatment of BCa.