Objective To study the impacts of curcumin on the proliferation, migration and cisplatin (DDP) resistance of bladder cancer cells by regulating the liver kinase B1-AMP activated protein kinase-microtubule-associated protein 1 light chain 3 (LKB1-AMPK-LC3) signaling pathway. Methods Human bladder cancer cell line T24 was cultured in vitro, and its DDP resistant T24/DDP cells were induced by cisplatin (DDP). After treating T24 and T24/DDP cells with different concentrations of curcumin, the optimal concentration of curcumin was screened by MTT assay. T24 cells were randomly grouped into control group, curcumin group, metformin group, and combination group of curcumin and metformin. After treatment with curcumin and LKB1-AMPK activator metformin, the proliferation, autophagy, migration, and apoptosis of T24 cells in each group were detected by MTT assay, monodansylcadavrine (MDC) fluorescence staining, cell scratch assay, and flow cytometry, respectively. Western blot was used to detect the expression of proteins related to LKB1-AMPK-LC3 signaling pathway in T24 cells of each group. T24/DDP cells were randomly assigned into control group, curcumin group, metformin group, and combination group of curcumin and metformin. Cells were treated with curcumin and metformin according to grouping and treated with different concentrations of DDP simultaneously. Then, the effect of curcumin on the DDP resistance coefficient of T24/DDP cells was detected by MTT assay. T24/DDP cells were randomly grouped into control group, DDP group, combination groups of DDP and curcumin, DDP and metformin, DDP, curcumin and metformi. After treatment with DDP, curcumin, and metformin, the proliferation, autophagy, migration, apoptosis, drug resistance, and the expression of proteins related to LKB1-AMPK-LC3 signaling pathway in T24/DDP cells of each group were detected with the same methods. Results Compared with the control group, the activity of T24 cells, relative number of autophagosomes, migration rate, Phosphorylated-LKB1 (p-LKB1)/LKB1, Phosphorylated-AMPK (p-AMPK)/AMPK, LC3II/LC3I, and the DDP resistance coefficient of T24/DDP cells in the curcumin group were lower, and the apoptosis rate of T24 cells was higher; the changes in various indicators in the metformin group were opposite to those in the curcumin group. Compared with the curcumin group, the activity of T24 cells, relative number of autophagosomes, migration rate, p-LKB1/LKB1, p-AMPK/AMPK, LC3II/LC3I, and the DDP resistance coefficient of T24/DDP cells in the combination group of curcumin and metformin were higher, and the apoptosis rate of T24 cells was lower. Compared with the control group, there were no obvious changes in various indicators of T24/DDP cells in the DDP group. Compared with the control group and DDP group, the viability of T24/DDP cells, relative number of autophagosomes, migration rate, P-glycoprotein (P-gp) protein expression, p-LKB1/LKB1, p-AMPK/AMPK, and LC3II/LC3I in the combination group of DDP and curcumin were lower, and the apoptosis rate of T24/DDP cells was higher; the changes in the above indicators in the combination group of DDP and metformin were opposite to those in the combination group of DDP and curcumin. Compared with the combination group of DDP and curcumin, the viability of T24/DDP cells, relative number of autophagosomes, migration rate, P-gp protein expression, p-LKB1/LKB1, p-AMPK/AMPK, and LC3II/LC3I in the combination group of DDP, curcumin and metformin were higher, and the apoptosis rate of T24/DDP cells was lower. Conclusion Curcumin can reduce the activity of LKB1-AMPK-LC3 signaling pathway, thereby inhibiting autophagy, proliferation and migration of bladder cancer cells, promoting their apoptosis, and weakening their resistance to DDP.
Humans ; Cisplatin/pharmacology* ; Curcumin/pharmacology* ; Cell Proliferation/drug effects* ; Signal Transduction/drug effects* ; Protein Serine-Threonine Kinases/genetics* ; AMP-Activated Protein Kinases/metabolism* ; Drug Resistance, Neoplasm/drug effects* ; Urinary Bladder Neoplasms/pathology* ; Cell Line, Tumor ; Cell Movement/drug effects* ; AMP-Activated Protein Kinase Kinases ; Microtubule-Associated Proteins/metabolism* ; Apoptosis/drug effects* ; Antineoplastic Agents/pharmacology* ; Metformin/pharmacology* ; Autophagy/drug effects*

OBJECTIVES: Bladder cancer is a common malignancy with high incidence and poor prognosis. N⁶-methyladenosine (m⁶A) modification is widely involved in diverse physiological processes, among which the m⁶A recognition protein YTH N⁶-methyladenosine RNA binding protein F2 (YTHDF2) plays a crucial role in bladder cancer progression. This study aims to elucidate the molecular mechanism by which O-linked N-acetylglucosamine (O-GlcNAc) modification of YTHDF2 regulates its downstream target, period circadian regulator 1 (PER1), thereby promoting bladder cancer cell proliferation. METHODS: Expression of YTHDF2 in bladder cancer was predicted using The Cancer Genome Atlas (TCGA). Twenty paired bladder cancer and adjacent normal tissues were collected at the clinical level. Normal bladder epithelial cells (SV-HUC-1) and bladder cancer cell lines (T24, 5637, EJ-1, SW780, BIU-87) were examined by quantitative real-time PCR (RT-qPCR), Western blotting, and immunohistochemistry for expression of YTHDF2, PER1, and proliferation-related proteins [proliferating cell nuclear antigen (PCNA), minichromosome maintenance complex component 2 (MCM2), Cyclin D1]. YTHDF2 was silenced in 5637 and SW780 cells, and cell proliferation was assessed by Cell Counting Kit-8 (CCK-8), colony formation, and EdU assays. Bioinformatics was used to predict glycosylation sites of YTHDF2, and immunoprecipitation (IP) was performed to detect O-GlcNAc modification levels of YTHDF2 in tissues and cells. Bladder cancer cells were treated with DMSO, OSMI-1 (O-GlcNAc inhibitor), or Thiamet G (O-GlcNAc activator), followed by cycloheximide (CHX), to assess YTHDF2 ubiquitination by IP. YTHDF2 knockdown and Thiamet G treatment were further used to evaluate PER1 mRNA stability, PER1 m⁶A modification, and cell proliferation. TCGA was used to predict PER1 expression in tissues; SRAMP predicted potential PER1 m⁶A sites. Methylated RNA immunoprecipitation (MeRIP) assays measured PER1 m⁶A modification. Finally, the effects of knocking down YTHDF2 and PER1 on 5637 and SW780 cell proliferation were assessed. RESULTS: YTHDF2 expression was significantly upregulated in bladder cancer tissues compared with adjacent tissues (mRNA: 2.5-fold; protein: 2-fold), which O-GlcNAc modification levels increased 3.5-fold (P<0.001). YTHDF2 was upregulated in bladder cancer cell lines, and its knockdown suppressed cell viability (P<0.001), downregulated PCNA, MCM2, and CyclinD1 (all P<0.05), reduced colony numbers 3-fold (P<0.01), and inhibited proliferation. YTHDF2 exhibited elevated O-GlcNAc modification in cancer cells. OSMI-1 reduced YTHDF2 protein stability (P<0.01) and enhanced ubiquitination, while Thiamet G exerted opposite effects (P<0.001). Thiamet G reversed the proliferation-suppressive effects of YTHDF2 knockdown, promoting cell proliferation (P<0.01) and upregulating PCNA, MCM2, and CyclinD1 (all P<0.05). Mechanistically, YTHDF2 targeted PER1 via m⁶A recognition, promoting PER1 mRNA degradation. Rescue experiments showed that PER1 knockdown reversed the inhibitory effect of YTHDF2 knockdown on cell proliferation, upregulated PCNA, MCM2, and Cyclin D1 (all P<0.05), and promoted bladder cancer cell proliferation (P<0.001). CONCLUSIONS O-GlcNAc modification YTHDF2 promotes bladder cancer development by downregulating the tumor suppressor gene PER1 through m⁶A-mediated post-transcriptional regulation.
Humans ; Urinary Bladder Neoplasms/metabolism* ; RNA-Binding Proteins/genetics* ; Cell Proliferation ; Cell Line, Tumor ; Disease Progression ; Acetylglucosamine/metabolism* ; Adenosine/metabolism* ; Gene Expression Regulation, Neoplastic ; Genes, Tumor Suppressor

OBJECTIVES: To explore the potential of pyrroline-5-carboxylate reductase 1 (PYCR1) as a pan-cancer biomarker and investigate its expression, function, and clinical significance in bladder cancer (BLCA). METHODS: Bioinformatics analysis was conducted to evaluate the associations of PYCR1 with prognosis, immune microenvironment remodeling, tumor mutation burden (TMB), and microsatellite instability (MSI) in cancer patients. Using the TCGA-BLCA dataset, univariate and multivariate regression analyses were performed to assess the potential of PYCR1 as an independent prognostic risk factor for BLCA, and a clinical decision model was constructed. The IMvigor210 cohort was utilized to evaluate the potential of PYCR1 for independently predicting the efficacy of immunotherapy. The pRRophetic was employed to screen candidate chemotherapeutic agents for treating BLCA with high PYCR1 expression. The CMap-XSum algorithm and molecular docking techniques were used to explore and validate small molecule inhibitors of PYCR1. RESULTS: A high expression of PYCR1 was significantly associated with poor prognosis, immune cell infiltration, TMB and MSI in various tumors (r>0.3). PYCR1 was overexpressed in BLCA, and high PYCR1 expression was closely related to poor prognosis in BLCA patients (HR: 1.14, 95% CI: 1.02-1.68, P=0.006). The IC₅₀ of the anti-cancer drugs cetuximab, 5-fluorouracil, and doxorubicin increased significantly in BLCA cell lines with high PYCR1 expressions (P<0.0001). CONCLUSIONS High PYCR1 expression is an independent risk factor for poor prognosis in BLCA patients and can serve as a significant indicator for clinical decision-making as well as a marker for predicting sensitivity to chemotherapeutic agents and the efficacy of immunotherapy.
Humans ; Urinary Bladder Neoplasms/genetics* ; Immunotherapy ; Prognosis ; Pyrroline Carboxylate Reductases/metabolism* ; Biomarkers, Tumor/genetics* ; delta-1-Pyrroline-5-Carboxylate Reductase ; Microsatellite Instability ; Tumor Microenvironment ; Mutation ; Computational Biology ; Molecular Docking Simulation

OBJECTIVES: To investigate the role of apelin in regulating proliferation, migration and angiogenesis of bladder cancer cells and the possible regulatory mechanism. METHODS: GEO database was used to screen the differentially expressed genes in bladder cancer tissues and cells. Bladder cancer and paired adjacent tissues were collected from 60 patients for analysis of apelin expressions in relation to clinicopathological parameters. In cultured bladder cancer J82 cells and human umbilical vein endothelial cells (HUVECs), the effects of transfection with an apelin-overexpressing plasmid or specific siRNAs targeting apelin, fibroblast growth factor 2 (FGF2) and fibroblast growth factor receptor 1 (FGFR1) on proliferation and migration of J82 cells and tube formation in HUVECs were examined using plate cloning assay, Transwell assay, and angiogenesis assay; the changes in FGF2 expression and FGFR1 phosphorylation were detected using Western blotting. RESULTS: The expression level of apelin was significantly higher in bladder cancer tissues than adjacent tissues, and bladder cancer cell lines (T24 and J82) also expressed higher mRNA and protein levels of apelin than SV-HUC-1 cells. Apelin expression level in bladder cancer tissues was correlated with tumor invasion, distant metastasis and advanced TNM stages. Apelin knockdown significantly suppressed proliferation and migration of J82 cells and decreased the total angiogenic length of HUVECs. In contrast, apelin overexpression significantly promoted proliferation and migration and enhanced FGFR1 phosphorylation in J82 cells, and increased the total angiogenesis length in HUVECs, but this effects were effectively mitigated by transfection of the cells with FGF2 siRNA or FGFR1 siRNA. CONCLUSIONS High expression of apelin promotes J82 cell proliferation and migration and HUVEC angiogenesis by promoting activation of the FGF2/FGFR1 pathway.
Humans ; Urinary Bladder Neoplasms/blood supply* ; Receptor, Fibroblast Growth Factor, Type 1/metabolism* ; Cell Proliferation ; Cell Movement ; Fibroblast Growth Factor 2/metabolism* ; Neovascularization, Pathologic ; Human Umbilical Vein Endothelial Cells ; Cell Line, Tumor ; Signal Transduction ; Apelin ; Intercellular Signaling Peptides and Proteins/genetics* ; Female ; Male ; Angiogenesis

OBJECTIVES: To investigate the inhibitory effect of pirfenidone (PFD) on growth of bladder cancer xenograft and its regulatory effect on Treg cells in tumor-bearing mice. METHODS: Thirty-two C57BL/6 mice bearing ectopic bladder tumors were randomized into control and PFD groups (n=16). In PFD group, PFD was administered orally at the daily dose of 500 mg/kg, and tumor growth and survival of the mice were monitored. After treatment for 21 days, the tumors and vital organs were harvested for analysis. Immunohistochemistry was used to assess CD3, CD4, CD8, and FOXP3 expressions in the tumors. Flow cytometry and RT-qPCR were used to analyze the percentage of CD4⁺CD25⁺FOXP3⁺ Treg cells and IL-2, IL-10, and IL-35 expressions in the tumors and spleens; organ damage of the mice was examined with HE staining. RESULTS: Compared with the control group, the PFD-treated mice exhibited significantly lower tumor growth rate with smaller tumor volumes at day 21, along with improved survival at day 28. Immunohistochemistry revealed no significant differences in the infiltration of CD3⁺ and CD8⁺ cells between the two groups, but the percentages of CD4⁺ and FOXP3⁺ cells were significantly lower in the tumors of PFD-treated mice. Flow cytometric analysis confirmed a decrease in CD4⁺CD25⁺FOXP3⁺ Treg cells in the tumors from PFD-treated mice, which also had reduced expression levels of IL-2, IL-10 and IL-35 mRNAs in the tumors. No significant differences were found in Treg cell populations or cytokine expressions in the spleen tissues between the two groups. HE staining showed obvious organ damage in neither of the groups. CONCLUSIONS PFD inhibits bladder cancer growth and enhances survival of tumor-bearing mice possibly by suppressing Treg cells in the tumor microenvironment.
Animals ; Urinary Bladder Neoplasms/drug therapy* ; Mice ; T-Lymphocytes, Regulatory/metabolism* ; Mice, Inbred C57BL ; Interleukins/metabolism* ; Interleukin-10/metabolism* ; Cell Line, Tumor ; Interleukin-2/metabolism* ; Xenograft Model Antitumor Assays ; Female

OBJECTIVE: To investigate the clinicopathological features and prognosis of urinary bladder urothelial carcinoma (UBUC) with incidental prostate cancer (IPCa). METHODS: We retrospectively analyzed the clinicopathological features of 65 cases of UBUC and 38 cases of UBUC + IPCa after radical cystoprostatectomy (RCP) from January 2017 to February 2020. We compared their expressions of the immunohistochemical markers androgen receptor (AR) and (human epidermal growth factor receptor 2,HER2) between the two groups of patients, and analyzed their clinicopathological characteristics by chi-square test and their survival rates using the Kaplan-Meier method and log-rank test. RESULTS: The detection rate of UBUC + IPCa was 16.5%, and that of clinically significant IPCa was 39.5%, with preoperative PSA≥4 μg/L in 23.7% of the patients. Compared with the patients with UBUC, most of the UBUC + IPCa cases had no smoking history (73.8% vs 92.1%, P = 0.024), and fewer had histological variants (43.1% vs 10.5%, P = 0.003). The incidence rate of vascular invasion was significantly higher in the UBUC than in the UBUC + IPCa group (49.2% vs 21.1%, P = 0.005), and so was the rate of advanced cases (67.7% vs 31.6%, P<0.001). In comparison with the patients of the UBUC group, those of the UBUC + IPCa group showed remarkably higher expressions of AR (9.2% vs 31.6%, P = 0.004) and HER2 (43.1% vs 71.1%, P = 0.006). The mean overall survival time was longer in the UBUC + IPCa than in the UBUC group (48.8 mo ［95% CI: 2.5－42.6 mo］ vs 39.9 mo ［95% CI: 2.8－34.5 mo］), but with no statistically significant difference between the two groups (P = 0.608). CONCLUSION Standardized sampling of prostate samples after RCP helps to improve the detection rate of IPCa. Preoperative level of PSA is not a good predictor of IPCa. Few patients with UBUC + IPCa have a history of cigarette smoking, and the predominant histological type of the malignancy is high-grade invasive urothelial carcinoma, which is not significantly different from UBUC in prognosis. The expressions of HER2 and AR are significantly higher in UBUC + IPCa than in UBUC, suggesting that UBUC + IPCa may benefit from HER2- and AR-targeted therapy.
Humans ; Male ; Urinary Bladder Neoplasms/metabolism* ; Receptors, Androgen/metabolism* ; Prostatic Neoplasms/metabolism* ; Retrospective Studies ; Receptor, ErbB-2/metabolism* ; Prognosis ; Middle Aged ; Aged ; Survival Rate ; Prostatectomy

Objective: To investigate the effect of long non-coding RNA urothelial carcinoma-associated 1 (UCA1) gene on the proliferation, migration, apoptosis and immune escape of endometrial cancer cells and its molecular mechanism. Methods: Endometrial cancer tissues and adjacent normal tissues of patients with endometrioid adenocarcinoma who underwent total or partial hysterectomy in Henan Provincial People's Hospital from 2017 to 2019 were collected. The expressions of UCA1 and miR-204-5p were detected by real-time fluorescence quantitative polymerase chain reaction (RT-qPCR), and the cell proliferation, migration and apoptosis were detected by cell counting kit 8 (CCK8) method, Transwell method, flow cytometry, and dual-luciferase reporter assay was used to explore the target relationship between UCA1 and miR-204-5p. HEC-1A-sh-NC or HEC-1A-sh-UCA1 cells were co-cultured with peripheral blood mononuclear cells (PBMC) or cytokine-induced killer cells in vitro to explore the role of UCA1 in immune escape. Results: The expression level of UCA1 in endometrial cancer tissue (17.08±0.84) was higher than that in adjacent normal endometrial tissue (3.00±0.37), and the expression level of miR-204-5p (0.98±0.16) was lower than that in adjacent normal endometrial tissue (2.00±0.20, P<0.05). Pearson correlation analysis showed that the expression of miR-204-5p was negatively correlated with the expression of UCA1 (r=-0.330, P=0.030). The expressions of UCA1 and miR-204-5p were associated with the International Federation of Gynecology and Obstetrics stage of endometrial cancer, lymph node metastasis and vascular invasion (P<0.05). The relative ratio of absorbance (0.58±0.11) and the number of cell migration [(199.68±18.44)] in the sh-UCA1 group were lower than those in the sh-NC group (1.24±0.17 and 374.76±24.83), respectively. The apoptosis rate of sh-UCA1 group [(28.64±7.80)%] was higher than that of sh-NC group [(14.27±4.38)%, P<0.05]. After different ratios of effector cells and target cells were cultured, the cell survival rate of HEC-1A-sh-UCA1 group was lower than that of HEC-1A-sh-NC group, and the difference was statistically significant (P<0.05). UCA1 had a binding site for miR-204-5p. The relative ratio of absorbance (1.74±0.08) and the number of cell migration (426.00±18.00) cells in the UCA1+ anti-miR-204-5p group were higher than those in the control group [1.00±0.03 and (284.00±8.00) cells, respectively]. The apoptosis rate of UCA1+ anti-miR-204-5p group [(5.42±0.93)%] was lower than that of control group [(14.82±1.48)%, P<0.05]. HEC-1A-sh-UCA1 cells could induce higher interferon gamma (IFN-γ) expression when co-cultured with PBMC, and the levels of IFN-γ expression in PHA group and PHA+ pre-miR-204-5p group cells were 2.42±0.49 and 1.88±0.26, which were higher than that in the PHA+ pre-NC group (0.85±0.10, P<0.05). When co-cultured with cytokine-induced killer cells (different ratios) in vitro, the HEC-1A-sh-UCA1 group and the HEC-1A-pre-miR-204-5p group had lower survival rates than that in the HEC-1A-pre-miR-204-5p group. In the HEC-1A-pre-NC group, the differences were statistically significant (P<0.05). Conclusion: UCA1/miR-204-5p may play an important role in human endometrial cancer.
Female ; Humans ; MicroRNAs/metabolism* ; RNA, Long Noncoding/genetics* ; Leukocytes, Mononuclear ; Carcinoma, Transitional Cell ; Antagomirs ; Cell Line, Tumor ; Urinary Bladder Neoplasms ; Cell Proliferation ; Endometrial Neoplasms/genetics* ; Apoptosis/genetics* ; Cell Movement/genetics* ; Gene Expression Regulation, Neoplastic

OBJECTIVE: To explore the influences of andrographolide (Andro) on bladder cancer cell lines and a tumor xenograft mouse model bearing 5637 cells. METHODS: For in vitro experiments, T24 cells were stimulated with Andro (0-40 µmol/L) and 5637 cells were stimulated with Andro (0 to 80 µmol/L). Cell growth, migration, and infiltration were assessed using cell counting kit-8, colony formation, wound healing, and transwell assays. Apoptosis rate was examined using flow cytometry. In in vivo study, the antitumor effect of Andro (10 mg/kg) was evaluated by 5637 tumor-bearing mice, and levels of nuclear factor κ B (NF- κ B) and phosphoinositide 3-kinase/AKT related-proteins were determined by immunoblotting. RESULTS: Andro suppressed growth, migration, and infiltraion of bladder cancer cells (P⩽0.05 or P⩽0.01). Additionally, Andro induced intrinsic mitochondria-dependent apoptosis in bladder cancer cell lines. Furthermore, Andro inhibited bladder cancer growth in mice (P⩽0.01). The expression of p65, p-AKT were suppressed by Andro treatment in vitro and in vivo (P⩽0.05 or P⩽0.01). CONCLUSIONS Andrographolide inhibits proliferation and promotes apoptosis in bladder cancer cells by interfering with NF- κ B and PI3K/AKT signaling in vitro and in vivo.
Animals ; Apoptosis ; Cell Line, Tumor ; Cell Proliferation ; Diterpenes/therapeutic use* ; Humans ; Mice ; NF-kappa B/metabolism* ; Phosphatidylinositol 3-Kinases/metabolism* ; Proto-Oncogene Proteins c-akt/metabolism* ; Urinary Bladder Neoplasms/drug therapy*

OBJECTIVES: Bladder cancer is one of the most common urothelial tumors with high incidence and mortality rates. Although it has been reported that microRNA (miR)-133b can regulate tumorigenesis of bladder cancer, the mechanism remains unclear. Sex-determining region Y-box transcription factor 4 (SOX4) exhibits an important role in tumorigenesis, but it is unclear whether SOX4 and miR-133b are associated with regulation of pathogenesis of bladder cancer. This study aims to determine the expressions of SOX4 and miR-133b in bladder cancer tissues and cells, investigate their effects on the proliferation, colony formation, and invasion of bladder cancer cells, and to explore the association between miR-133b and SOX4 in regulating biological featurss of bladder cancer cells. METHODS: The bladder cancer and adjacent tissue samples of 10 patients who underwent surgical resection in the Second Xiangya Hospital of Central South Universty from Januray to June 2015 were obtained. The levels of miR-133b were tested by real-time PCR, and the protein levels of SOX4 were evaluated using Western blotting in bladder cancer tissues, matched adjacent tissues, and cell lines. The correlation between miR-133b expression and SOX4 expression in bladder cancer tissues was analyzed. Using the online database TargetScan, the relationship between SOX4 and miR-133b was predicted. MiR-133b mimics, miR-133b inhibitor, and short hairpin RNA (shRNA)-SOX4 were transfected into T24 cells by Lipofectamine 2000. The relationship between miR-133b and SOX4 was also verified by a dual-luciferase reporter assay. The proliferation of T24 cells cultured for 0, 12, 48, 72, and 96 h was evaluated by cell counting kit-8 (CCK-8) assay. The colony formation capacity of bladder cancer cells was tested after 14-day culture, and cell invasion capacity was evaluated with Transwell invasion assay. RESULTS: Bladder cancer tissue and bladder cancer cells had low level of miR-133b but high level of SOX4, compared with matched adjacent tissues and normal bladder epithelial cells. A negative correlation between miR-133b mRNA and SOX4 protein levels in bladder cancer tissues was also found (r=-0.84). The results of online database TargetScan showed that miR-133b targets at SOX4, and overexpression of miR-133b significantly attenuated the expression of SOX4 in T24 cells. Both overexpression of miR-133b and knockdown of SOX4 significantly inhibited the proliferation, colony formation, and invasion capacity of bladder cancer cells in vitro. SOX4 down-regulation restored the effects of miR-133b inhibitor on the proliferation, colony formation, and invasion capacity of T24 cells. CONCLUSIONS The up-regulation of SOX4 contributes to the progression of bladder cancer, and miR-133b can regulate the proliferation, colony formation, and invasion of bladder cancer cells via inhibiting SOX4.
Carcinogenesis/genetics* ; Cell Line, Tumor ; Cell Movement/genetics* ; Cell Proliferation/genetics* ; Epithelial Cells/metabolism* ; Gene Expression Regulation, Neoplastic ; Humans ; MicroRNAs/genetics* ; SOXC Transcription Factors/genetics* ; Urinary Bladder ; Urinary Bladder Neoplasms/genetics*

OBJECTIVE: To explore the molecular mechanism by which microRNA let-7g-3p regulates biological behaviors of bladder cancer cells. METHODS: The expression levels of let-7g-3p in bladder cancer and adjacent tissues, normal bladder epithelial cells (HUC cells) and bladder cancer cells (T24, 5637 and EJ cells) were detected using qRT- PCR. T24 cells were transfected with let-7g-3p mimic or inhibitor, and the changes in cell proliferation, migration, invasion, and apoptosis were examined. Transcriptome sequencing was carried out in cells overexpressing let-7g-3p, and the results of bioinformatics analysis, double luciferase reporter gene assay, qRT-PCR and Western blotting confirmed that HMGB2 gene was the target gene of let-7g-3p. The expression of HMGB2 was examined in HUC, T24, 5637 and EJ cells, and in cells with HMGB2 knockdown, the effect of let-7g-3p knockdown on the biological behaviors were observed. RESULTS: qRT-qPCR confirmed that let-7g-3p expression was significantly lower in bladder cancer tissues and cells (P < 0.01). Overexpression of let-7g-3p inhibited cell proliferation, migration and invasion, and promoted cell apoptosis, while let-7g-3p knock-down produced the opposite effects. Bioinformatics and transcriptome sequencing results showed that HMGB2 was the key molecule that mediate the effect of let-7g-3p on bladder cancer cells. Luciferase reporter gene assay, qRT-PCR and Western blotting all confirmed that HMGB2 was negatively regulated by let-7g-3p (P < 0.01). Knocking down HMGB2 could partially reverse the effect of let-7g-3p knockdown on the biological behaviors of the bladder cancer cells. CONCLUSION The microRNA let-7g-3p can inhibit the biological behavior of bladder cancer cells by negatively regulating HMGB2 gene.
Apoptosis ; Cell Line, Tumor ; Cell Movement/physiology* ; Cell Proliferation ; Epithelial Cells/metabolism* ; Gene Expression Regulation, Neoplastic ; HMGB2 Protein/metabolism* ; Humans ; MicroRNAs/metabolism* ; Urinary Bladder ; Urinary Bladder Neoplasms/genetics*