Knockdown of AMIGO2 suppresses proliferation and migration through regulating PPAR-γ in bladder cancer.

PURPOSE: This study aims to reveal the relationship between AMIGO2 and proliferation, migration and tumorigenicity of bladder cancer, and explore the potential molecular mechanisms. METHODS: The expression level of AMIGO2 is measured by qRT-PCR and immunohistochemistry (IHC). Stable AMIGO2 knockdown cell lines T24 and 5637 were established by lentivirus transfection. Cell Counting Kit (CCK-8 assay) was produced to determine cell proliferation, flow cytometry analysis was utilized to detect cell cycle, and wound healing assay was proceeded to test migration ability of bladder cancer cells. Xenograft mouse model was established for investigating the effect of AMIGO2 on tumor formation in vivo. The RNA Sequencing technology was applied to explore the underlying mechanisms. The expression level of PPAR-γ was measured by Western Blot. RESULTS: AMIGO2 was upregulated in bladder cancer cells and tissues. Inhibited expression of AMIGO2 suppresses cell proliferation and migration. Low AMIGO2 expression inhibited tumorigenicity of 5637 in nude mice. According to RNA-Seq and bioinformatics analysis, 917 DEGs were identified. The DEGs were mainly enriched in cell-cell adhesion, peroxisome proliferators-activated receptors (PPARs) signaling pathway and some other pathways. PPAR-γ is highly expressed in bladder cancer cell lines T24 and 5637, but when AMIGO2 is knocked down in T24 and 5637, the expression level of PPAR-γ is also decreased, and overexpression of PPAR-γ could reverse the suppression effect of cell proliferation and migration caused by the inhibition of AMIGO2. CONCLUSION: AMIGO2 is overexpressed in bladder cancer cells and tissues. Knockdown of AMIGO2 suppresses bladder cancer cell proliferation and migration. These processes might be regulated by PPAR-γ signaling pathway.

Comparison of 3 and 4 cycles of neoadjuvant gemcitabine and cisplatin for muscle-invasive bladder cancer: a systematic review and meta-analysis.

BACKGROUND: In muscle-invasive bladder cancer (MIBC), neoadjuvant chemotherapy (NAC) combined with radical cystectomy (RC) is critical in reducing disease recurrence, with GC (gemcitabine and cisplatin) being one of the most commonly used NACs. Different GC schedules have been used, but the best neoadjuvant regimen is still unknown. The clinical outcomes of 3 and 4 cycles of neoadjuvant GC are compared in this systematic review and meta-analysis to determine which is best for patients with MIBC. METHODS: We searched PubMed, Embase, Web of Science, Cochrane Library, CBM, CNKI, WAN FANG DATA, and meeting abstracts to identify relevant studies up to March 2023. Studies that compared 3 and 4 cycles of neoadjuvant GC for MIBC were included. The primary outcomes were pCR, pDS, OS, and CSS. The secondary outcome was recurrence and SAEs. RESULTS: A total of 3 studies, with 1091 patients, were included in the final analysis. Patients that received 4 cycles of GC had a higher pCR (OR = 0.66; 95% CI, 0.50-0.87; p = 0.003) and pDS (OR = 0.63; 95% CI, 0.48-0.84; p = 0.002) than those who received 3 cycles. Regarding recurrence rate (OR = 1.23; 95% CI, 0.91-1.65; p = 0.18), there were no appreciable differences between the 3 and 4 cycles of GC. Survival parameters such as OS (HR, 1.35; 95% CI, 0.86-2.12; p = 0.19) and CSS (HR, 1.06; 95% CI, 0.82-1.38; p = 0.20) were similar. Only one trial reported on the outcomes of SAEs. And there were no statistically significant differences in thrombocytopenia, infection rate, neutropenic fever, anemia, or decreased renal function between patients. The neutropenia of patients was statistically different (OR = 0.72; 95% CI, 0.52-0.99; p = 0.04). CONCLUSION: The 4-cycle GC regimen was superior to the 3-cycle regimen in only the pCR and pDS results. Survival and recurrence rates were similar between the two regimens. In both treatment regimes, the toxicity profile was manageable. However, due to the inherent drawbacks of retrospective research, this should be regarded with caution.

CAB39 promotes cisplatin resistance in bladder cancer via the LKB1-AMPK-LC3 pathway.

Systemic therapy for muscle-invasive bladder cancer (BC) remains dominated by cisplatin-based chemotherapy. However, resistance to cisplatin therapy greatly limits long-term survival. Resistance to cisplatin-based chemotherapy still needs to be addressed. In this study, we established three cisplatin-resistant BC cell lines by multiple cisplatin pulse treatments. Interestingly, after exposure to cisplatin, all cisplatin-resistant cell lines showed lower reactive oxygen species (ROS) levels than the corresponding parental cell lines. Using proteomic analysis, we identified 35 proteins that were upregulated in cisplatin-resistant BC cells. By knocking down eleven of these genes, we found that after CAB39 knockdown, BC cisplatin-resistant cells were more sensitive to cisplatin. Overexpression of CAB39 had the opposite effect. Then, the knockdown of six genes downstream of CAB39 revealed that CAB39 promoted cisplatin resistance in BC through LKB1. Moreover, a key cause of cisplatin-induced cell death is damage to mitochondria and increased ROS levels. In our study, cisplatin-resistant cells exhibited higher autophagic flux and healthier mitochondrial status after cisplatin exposure. We demonstrated that the CAB39-LKB1-AMPK-LC3 pathway plays a critical role in enhancing autophagy to maintain the health of mitochondria and reduce ROS levels. In addition, the autophagy inhibitor chloroquine (CQ) can significantly enhance the killing effect of cisplatin on BC cells. Compared with gemcitabine plus cisplatin (GC), GC plus CQ significantly reduced tumor burden in vivo. In conclusion, our study shows that CAB39 counteracts the killing of cisplatin by enhancing the autophagy of BC cells to damaged mitochondria and other organelles to alleviate the damage of cells caused by harmful substances such as ROS.

ADAM12 promotes gemcitabine resistance by activating EGFR signaling pathway and induces EMT in bladder cancer.

BACKGROUND: Gemcitabine (GEM)-based chemotherapy regimens is widely used in bladder cancer (BC) patients. However, GEM resistance may occur and result in treatment failure and disease progression. A disintegrin and metalloprotease 12 (ADAM12) plays a critical role in many cancers. However, the role of ADAM12 in GEM resistance of BC remains unclear. METHODS: We analyzed the relationship between ADAM12 expression and tumor characteristics using the data downloaded from The Cancer Genome Atlas (TCGA) database and Gene Expression Omnibus (GEO) database. Then, we established GEM resistant BC cell lines and used quantitative real-time PCR, western blot, cell counting kit-8, immunohistochemistry, and xenograft mouse model to investigate the role of ADAM12 in GEM resistance. RESULTS: In general, ADAM12 was found to be upregulated in GEM resistant BC cells. ADAM12 knockdown increased the chemosensitivity of BC cells. We further proved that ADAM12 could promote GEM resistance by activating the epidermal growth factor receptor (EGFR) signaling pathway in BC. Furthermore, the epithelial-mesenchymal transition (EMT) phenotype was observed in GEM resistant BC cells. ADAM12 induced EMT process and promotes tumor progression in BC. CONCLUSION: Our findings suggested that ADAM12 was a key gene for GEM resistance and positively correlated with malignancy of BC. It might serve as a novel and valuable therapeutic target for BC.

Homologous Recombination Related Signatures Predict Prognosis and Immunotherapy Response in Metastatic Urothelial Carcinoma.

Objective: This study used homologous recombination (HR) related signatures to develop a clinical prediction model for screening immune checkpoint inhibitors (ICIs) advantaged populations and identify hub genes in advanced metastatic urothelial carcinoma. Methods: The single-sample gene enrichment analysis and weighted gene co-expression network analysis were applied to identify modules associated with immune response and HR in IMvigor210 cohort samples. The principal component analysis was utilized to determine the differences in HR-related module gene signature scores across different tissue subtypes and clinical variables. Risk prediction models and nomograms were developed using differential gene expression analysis associated with HR scores, least absolute shrinkage and selection operator, and multivariate proportional hazards model regression. Additionally, hub genes were identified by analyzing the contribution of HR-related genes to principal components and overall survival analysis. Finally, clinical features from GSE133624, GSE13507, the TCGA, and other data sets were analyzed to validate the relationship between hub genes and tumor growth and mutation. Results: The HR score was significantly higher in the complete/partial response group than in the stable/progressive disease group. The majority of genes associated with HR were discovered to be involved in the cell cycle and others. Genomically unstable, high tumor level, and high immune level samples all exhibited significantly higher HR score than other sample categories, and higher HR scores were related to improved survival following ICIs treatment. The risk scores for AUNIP, SEPT, FAM72D, CAMKV, CXCL9, and FOXN4 were identified, and the training and verification groups had markedly different survival times. The risk score, tumor neoantigen burden, mismatch repair, and cell cycle regulation were discovered to be independent predictors of survival time following immunotherapy. Patients with a high level of expression of hub genes such as EME1, RAD51AP1, and RAD54L had a greater chance of surviving following immunotherapy. These genes are expressed at significantly higher levels in tumors, high-grade cancer, and invasive cancer than other categories, and are associated with TP53 and RB1 mutations. Conclusion: HR-related genes are upregulated in genomically unstable samples, the survival time of mUC patients after treatment with ICIs can be predicted using a normogram model based on HR signature.

[Methods for androgen receptor splice variant-7 detection: Advances in studies].

Treatment strategies for castration-resistant prostate cancer (CRPC) mainly include taxane-based chemotherapy, novel endocrine therapy, and immunotherapy with radium 233. At present, there have been no clinical biomarkers for the prediction of the therapeutic effects and guidance with the medication in the treatment of CRPC. A large number of studies have shown that the androgen receptor splice variant-7 (AR-V7) is associated with the resistance to abiraterone and enzalutamide but not to Taxanes. So AR-V7 is expected to become a clinically useful tumor marker for predicting the clinical efficacy and guiding medication selection. However, the methods for the detection of AR-V7 present a challenge before its clinical application. This review introduces different methods of AR-V7 detection in the existing studies and looks forward to the clinical application of AR-V7 in order to move AR-V7 from the bench to the bedside.