CircUGGT2 facilitates progression and cisplatin resistance of bladder cancer through nonhomologous end-joining pathway.

The development of resistance to cisplatin (CDDP) in bladder cancer presents a notable obstacle, with indications pointing to the substantial role of circular RNAs (circRNAs) in this resistance. Nevertheless, the precise mechanisms through which circRNAs govern resistance are not yet fully understood. Our findings demonstrate that circUGGT2 is significantly upregulated in bladder cancer, facilitating cancer cell migration and invasion. Additionally, our analysis of eighty patient outcomes revealed a negative correlation between circUGGT2 expression levels and prognosis. Using circRNA pull-down assays, mass spectrometry analyses, and RNA Immunoprecipitation (RIP), it was shown that circUGGT2 interacts with the KU heterodimer, consisting of KU70 and KU80. Both KU70 and KU80 are critical components of the non-homologous end joining (NHEJ) pathway, which plays a role in CDDP resistance. Flow cytometry was utilized in this study to illustrate the impact of circUGGT2 on the sensitivity of bladder cancer cell lines to CDDP through its interaction with KU70 and KU80. Additionally, a reduction in the levels of DNA repair factors associated with the NHEJ pathway, such as KU70, KU80, DNA-PKcs, and XRCC4, was observed in chromatin of bladder cancer cells following circUGGT2 knockdown post-CDDP treatment, while the levels of DNA repair factors in total cellular proteins remained constant. Thus, the promotion of CDDP resistance by circUGGT2 is attributed to its facilitation of repair factor recruitment to DNA breaks via interaction with the KU heterodimer. Furthermore, our study demonstrated that knockdown of circUGGT2 resulted in reduced levels of γH2AX, a marker of DNA damage response, in CDDP-treated bladder cancer cells, implicating circUGGT2 in the NHEJ pathway for DNA repair.

Interaction between Wnt/ß-catenin signaling pathway and EMT pathway mediates the mechanism of sunitinib resistance in renal cell carcinoma.

BACKGROUND: Targeted drugs are the main methods of RCC treatment. However, drug resistance is common in RCC patients, in-depth study of the drug-resistant mechanism is essential. METHODS: We constructed sunitinib resistant and Twist overexpressed A498 cells, and studied its mechanisms in vitro and in vivo. RESULTS: In cell research, we found that either sunitinib resistance or Twist overexpression can activate Wnt/ß-catenin and EMT signaling pathway, and the sunitinib resistance may work through ß-catenin/TWIST/TCF4 trimer. In zebrafish research, we confirmed the similarity of Twist overexpression and sunitinib resistance, and the promoting effect of Twist overexpression on drug resistance. CONCLUSIONS: Sunitinib resistance and Twist overexpression can activate Wnt/ß-catenin signaling pathway and EMT to promote the growth and metastasis of RCC cells.

Knockdown of Circ_CCNB2 Sensitizes Prostate Cancer to Radiation Through Repressing Autophagy by the miR-30b-5p/KIF18A Axis.

Background: Circular RNAs (circRNAs) have recently emerged as crucial regulatory molecules in prostate cancer (PCa), but few researches focus on the effects of circRNAs on PCa radiosensitivity. The issue will be addressed in this study using circRNA Cyclin B2 (circ_CCNB2) as an object. Materials and Methods: All RNA and protein levels were severally examined using quantitative real-time polymerase chain reaction and Western blot. Colony formation assay and flow cytometry were implemented for detecting cell colony capacity and apoptotic cells, respectively. Cellular migration and invasion abilities were evaluated by transwell assay. The combination between potential target molecules was analyzed by dual-luciferase reporter and RNA immunoprecipitation (RIP) assays. The effect of circ_CCNB2 on PCa radiosensitivity in vivo was explored using xenograft models in mice. Results: Circ_CCNB2 was upregulated in irradiation-resistant PCa tissues and cells. Circ_CCNB2 knockdown had promoted effect on the radiosensitivity of irradiation-resistant PCa cells by inhibiting autophagy. Besides, circ_CCNB2 could directly sponge miR-30b-5p, and the promotion of circ_CCNB2 knockdown on PCa radiosensitivity was achieved by elevating miR-30b-5p. MiR-30b-5p enhanced the radiosensitivity of irradiation-resistant PCa cells through repressing the expression of its target kinesin family member 18A (KIF18A). Furthermore, circ_CCNB2 regulated the KIF18A level through targeting miR-30b-5p. Circ_CCNB2 downregulation facilitated PCa radiosensitivity in vivo through inhibiting autophagy by miR-30b-5p/KIF18A. Conclusions: In this study, knockdown of circ_CCNB2 was shown to promote PCa radiosensitivity through autophagy repression by miR-30b-5p/KIF18A axis, developing a molecular resistance mechanism of PCa radiotherapy and a feasible strategy to increase radiosensitivity.

LINC00460 Enhances Bladder Carcinoma Cell Proliferation and Migration by Modulating miR-612/FOXK1 Axis.

INTRODUCTION: LincRNA (long intergenic noncoding RNA) has been indicated as a mediator in tumorigenesis of bladder carcinoma. This study was performed to evaluate the role of LINC00460 in bladder carcinoma progression. METHODS: Expression levels of LINC00460 in bladder carcinoma tissues and cell lines were analyzed via qRT-PCR. MTT, EdU (5-ethynyl-2'-deoxyuridine) staining, and colony formation assays were utilized to evaluate cell viability and proliferation. The wound healing assay was performed to evaluate bladder cancer cell migration, and the transwell assay was used to evaluate cell invasion. The microRNA (miRNA) target of LINC00460 and the corresponding target gene were validated via the dual luciferase activity assay. The tumorigenic function of LINC00460 was determined via establishment of a xenotransplanted tumor model. RESULTS: LINC00460 was elevated in bladder carcinoma tissues and cell lines. Elevated LINC00460 was associated with shorter overall survival of bladder carcinoma patients. Overexpression of LINC00460 promoted cell viability, proliferation, invasion, and migration, while silencing of LINC00460 indicated the opposite effect on bladder carcinoma progression. LINC00460 could directly bind to miR-612 and inhibit miR-612 expression. Moreover, LINC00460 expression was negatively correlated with miR-612 in patients with bladder carcinoma. FOXK1 (Forkhead Box K1) was identified as the target of miR-612 and upregulated in patients with bladder carcinoma. Overexpression of FOXK1 attenuated interference of LINC00460-inhibited bladder carcinoma progression. Knockdown of LINC00460 suppressed in vivo bladder carcinoma growth. CONCLUSIONS: LINC00460 promoted bladder carcinoma progression via sponging miR-612 to facilitate FOXK1 expression, suggesting that LINC00460 might have the potential of being explored as a therapeutic target for treatment of bladder carcinoma.

Long Non-Coding RNA SNHG1 Regulates the Wnt/ß-Catenin and PI3K/AKT/mTOR Signaling Pathways via EZH2 to Affect the Proliferation, Apoptosis, and Autophagy of Prostate Cancer Cell.

BACKGROUND: Prostate cancer (PCa) is the most common malignant cancer in western developed countries, which has seriously threatened the life style and life quality of men. Its pathogenesis and causes remain indistinct. Currently, it is found that lncRNA-SNHG1 (SNHG1) is highly expressed in multiple tumors with proto-oncogene effect, but its function and mechanism in PCa need to be further studied. METHODS: The expression of SNHG1 and EZH2 was detected by RT-qPCR in the 20 pairs of PCa tissue, adjacent tissue and PCa cell lines. They were transfected with siRNA NC, SNHG1 siRNA, EZH2 siRNA, SNHG1 siRNA+empty, and SNHG1 siRNA+EZH2 overexpression. Then, MTT and colony formation assay were used to detect the proliferation and cloning ability of PCa cells LNCaP and PC3. Transwell and flow cytometry were used to measure cell migration and invasion ability and apoptosis level respectively. Immunofluorescence was used to detect the LC3 spot formation. Western blot was used to detect the expression of the autophagy-related proteins, and PI3K/AKT/mTOR and Wnt/ß-catenin signaling pathway related proteins. Finally, in vivo nude mice tumorigenesis experiment to explore the effect of SNHG1 expression on PCa. RESULTS: We found that SNHG1 and EZH2 were up-regulated in PCa tissue and cells. The expression of SNHG1 and EZH2 was positively correlated. RNA pull down and RNA IP assay further confirmed that SNHG1 bound to EZH2. The proliferation, colony formation, migration and invasion of LNCaP and PC3 cells were significantly reduced with the interference with SNHG1or EZH2 compared with the control group. The related proteins of Wnt/ß-catenin and PI3K/AKT/mTOR signaling pathway were significantly reduced after the interference with SNHG1 or EZH2; after simultaneous interference with SNHG1 and overexpression of EZH2, the functional effects on LNCaP and PC3 cells interfered with SNHG1 were reversed. These results were also confirmed in vivo nude mice tumor formation experiments. CONCLUSIONS: This study reveals that lncRNA-SNHG1 regulates Wnt/ß-catenin and PI3K/AKT/mTOR signaling pathways via EZH2 gene to affect proliferation, apoptosis and autophagy of PCa cells. This experiment provides ideas and experimental basis for the improvement and treatment of PCa.

Rubimaillin suppresses proliferation, migration and invasion of prostate cancer cells via the Notch-1/MMP signaling pathway.

This study was aimed to explore the effect of Rubimaillin on the survival, migration, and invasion of prostate cancer cell lines DU145 and PC3, and its mechanism. CCK-8 method was used to detect the effects of different concentrations of rubs (0, 5, 10, 20, 40 and 80 µM) on the activity of DU145 cells and PC3 cells. Transwell cell lab test was used to detect the migration and invasion of cells. Western blot was used to detect Notch-1, MMP-2, MMP-9 and Hes-1 protein levels. The CCK-8 assay showed that Rub inhibited the activity of Du145 and PC3 cells in a concentration dependent manner. When the concentration reached 40 µM, the inhibition reached the maximum. After Rub intervention, the migration and invasion ability of Du145 and PC3 cells decreased significantly, while the expression levels of Notch-1, MMP-2, MMP-9 and Hes-1 protein decreased significantly. Rub can inhibit the growth, migration and invasion of prostate cancer cell line DU145 and PC3. The mechanism may be related to the inhibition of Notch-1, MMP-2, MMP-9 and Hes-1 by Rub.

Isorhamnetin inhibited the proliferation and metastasis of androgen-independent prostate cancer cells by targeting the mitochondrion-dependent intrinsic apoptotic and PI3K/Akt/mTOR pathway.

The present study investigated the effects of Isorhamnetin on two types of prostate cancer cells (androgen-independent and androgen-dependent) and explored its possible mechanisms underlying such effects. Treatment with Isorhamnetin significantly inhibited cell growth and induced lactate dehydrogenase (LDH) release of androgen-independent DU145 and PC3 prostate cancer cells, but exhibited almost no toxicity effect on androgen-dependent LNCaP prostate cancer cell line or normal human prostate epithelial PrEC cells, which was achieved by the induction of apoptosis in a mitochondrion-dependent intrinsic apoptotic pathway. Furthermore, Isorhamnetin inhibited cell migration and invasion in concentration-dependent manners by enhancing mesenchymal-epithelial transition (MET) and inhibiting matrix metalloproteinase (MMP) 2 (MMP-2) and MMP-9 overexpression. In addition, Isorhamnetin also down-regulated the expression of phosphorylated PI3K (p-P13K), Akt (p-Akt), and mTOR (p-mTOR) proteins in both cancer cells, revealing Isorhamnetin to be a selective PI3K-Akt-mTOR pathway inhibitor. In summary, these findings propose that Isorhamnetin might be a novel therapeutic candidate for the treatment of androgen-independent prostate cancer.

Widowed status predicts poor overall survival of Chinese patients with prostate cancer.

BACKGROUND: Little is known about the influence of marital status on Chinese prostate cancer (PCa) patients. Marital status may have an impact on overall survival in Chinese men with prostate cancer. METHODS: We identified 4,208 Chinese patients diagnosed with PCa between 2004 and 2015 in the Surveillance, Epidemiology, and End Results (SEER) database. Univariate and multivariate Cox proportional hazard models were used to determine the impact of marital status on the overall survival (OS) of Chinese PCa patients. Survival analysis was performed using the Kaplan-Meier method. Smoothing function and threshold effect analysis were performed to determine the turning points of variables. RESULTS: Univariate analysis demonstrated that marital status, prostate-specific antigen (PSA) category, surgery status, T stage, N stage, and M stage were associated with OS. Multivariate analysis further indicated that marital status, PSA category, surgery status, T stage, and M stage were independent risk factors of OS. Survival analysis demonstrated that the nonwidowed group had a better OS than the widowed group. The risk of poor OS increased rapidly with the PSA level up to the turning point 15.6 and 45.4 ng/mL in the nonwidowed group (HR =1.089; 95% CI: 1.064-1.115; P<0.0001) and the widowed group (HR =1.056; 95% CI: 1.028-1.084; P<0.001), respectively. CONCLUSIONS: In conclusion, this study demonstrated that widowed status greatly affects the OS of Chinese PCa patients. Altogether, this study highlights the importance of psychological intervention, especially for widowed Chinese PCa patients. Timely psychological intervention for widowed Chinese PCa patients might improve the survival outcomes of PCa.

ALDOLASE A regulates invasion of bladder cancer cells via E-cadherin-EGFR signaling.

Glycolysis and glycogenesis are known to be tightly associated with cancer cell migration. However, their roles in bladder cancer have not been reported. In this study, ALDOLASE A (ALDOA) was identified in a coexpression network generated using glycolysis- and glycogenesis-related genes in Kyoto Encyclopedia of Genes and Genomes. ALDOA was located in the central region in the network, and the cancer genome atlas (TCGA) data suggest that ALDOA expression levels are associated with viability in patients with cancer at the middle and late stages. Bladder cancer cell lines, T24 and RT4, were used to knockdown (sh) or overexpress (OE) ALODA to analyze its role. The sh-ALDOA reduced cell viability, colony formation rate, and invasion cell number; while OE had an opposite effect compared with sh-ALDOA. Further, the sh-ALDOA expression induced E-cadherin level while reduced N-cadherin and vimentin levels. The OE cells reduced E-cadherin and induced N-cadherin and vimentin levels. In addition, epidermal growth factor receptor (EGFR), mitogen-activated protein kinase (MAPK), and AKT serine/threonine kinase (AKT) phosphorylation levels are all reduced in sh-ALODA while activated in OE cells compared with the control group. But either sh-ALODA or OE did not change total protein levels of EGFR, MAPK, and AKT. To further analyze E-cadherin function in ALDOA regulation on bladder cancer cells, sh-ALDOA and sh-E-cadherin were cotransfected in T24 and RT4 cells. The results indicated that sh-ALDOA and sh-E-cadherin expressions eliminated sh-ALDOA function, resulting similar cell viability, colony formation rate, and invasion cell number with control group. Also, sh-ALDOA and shE-cadherin expressions increased EGFR, MAPK, and AKT phosphorylation levels; and the levels were similar to the control group. But, sh-ALDOA and sh-E-cadherin expressions did not change N-cadherin and vimentin levels, which maintain similar levels with sh-ALDOA-expressing cells. Taken together, these results suggest that ALDOA might play an important function in bladder cancer and its action may be though E-cadherin-EGFR signaling.