Expression and prognostic significance of pyruvate dehydrogenase kinase 1 in bladder urothelial carcinoma

Circ_0002395 promotes aerobic glycolysis and proliferation in pancreatic adenocarcinoma cells via miR-548c-3p/PDK1 axis

Circular RNAs (circRNAs) showing unusual expressions have been discovered in pancreatic adenocarcinoma (PAAD). However, the functions and underlying mechanisms of these circRNAs still remain largely unclear. Our current study discovered a notable increase in the expression of circRNA hsa_circ_0002395 (circ_0002395) in both PAAD tissues and cell lines. This up-regulation of circ_0002395 was found to be associated with larger tumor sizes and lymph node metastasis. Furthermore, our findings showed that circ_0002395 facilitated aerobic glycolysis and cell proliferation in PAAD cells by regulating the miR-548c-3p/PDK1 axis. Mechanistically, we identified circ_0002395 as a competing endogenous RNA (ceRNA) that sponged miR-548c-3p, thereby promoting PDK1 expression and aerobic glycolysis, and ultimately resulting in the enhancement of cell proliferation. Our findings found that circ_0002395 promoted proliferation of PAAD cells by enhancing PDK1 expression and aerobic glycolysis by sponging miR-548c-3p.

The Role of Hypoxia-inducible Factor-1 in Bladder Cancer

Bladder cancer (BC) is one of the most common malignant tumors worldwide and poses a significant hazard to human health. During the development of BC, hypoxia plays a crucial role. Hypoxia-inducible factor (HIF) is a key transcription factor for hypoxic adaptation, which regulates the transcription of various genes, including inflammation, angiogenesis, and glycolytic metabolism. Recent studies have shown the precise role of HIF in various biological behaviors of BC. More importantly, a new antitumor medication targeting HIF-2 has been used to treat renal cancer. However, therapies targeting HIF-1 in BC have not yet been developed. In this review, we discussed how HIF-1 is expressed and affects the growth, metastasis, and angiogenesis of BC. At the same time, we investigated several HIF-1 inhibitors that provide new perspectives for targeting HIF-1.

Lymph Node Dissection in Upper Tract Urothelial Carcinoma: Current Status and Future Perspectives

PURPOSE OF REVIEW

This narrative review aims to evaluate the role of lymph node dissection (LND) in upper tract urothelial carcinoma (UTUC) and its implications for staging and management outcomes, as well as future perspectives.

RECENT FINDINGS

Multiple studies have demonstrated the limitations of conventional imaging techniques in accurately localizing lymph node metastasis (LNM) in UTUC. While 18F-fluorodeoxyglucose positron emission tomography with computed tomography (18FDG-PET/CT) shows promise for preoperative LNM detection, its specificity is low. Alternative methods such as choline PET/CT and sentinel lymph node detection are under consideration but require further investigation. Additionally, various preoperative factors associated with LNM hold potential for predicting nodal involvement, thereby improving nodal staging and oncologic outcomes of LND. Several surgical approaches, including segmental ureterectomy and robot-assisted nephroureterectomy, provide a possibility for LND, while minimizing morbidity. LND remains the primary nodal staging tool for UTUC, but its therapeutic benefit is still uncertain. Advances in imaging techniques and preoperative risk assessment show promise in improving LNM detection. Further research and multi-center studies are needed to comprehensively assess the advantages and limitations of LND in UTUC, as well as the long-term outcomes of alternative staging and treatment strategies.

Glucose Metabolism Reprogramming in Bladder Cancer: Hexokinase 2 (HK2) as Prognostic Biomarker and Target for Bladder Cancer Therapy

Proliferating cancer cells are able to reprogram their energy metabolism, favouring glycolysis even in the presence of oxygen and fully functioning mitochondria. Research is needed to validate the glycolysis-related proteins as prognostic/predictive biomarkers in urothelial bladder carcinoma (UBC), a malignancy tagged by high recurrence rates and poor response to chemotherapy. Here, we assessed GLUT1, HK2, PFKL, PKM2, phospho-PDH, and LDHA immunoexpression in 76 UBC samples, differentiating among urothelial, fibroblast, and endothelial cells and among normoxic versus hypoxic areas. We additionally studied the functional effects of the HK2 inhibitor 2-deoxy-D-glucose (2DG) in "in vitro" and "in vivo" preclinical UBC models. We showed that the expression of the glycolysis-related proteins is associated with UBC aggressiveness and poor prognosis. HK2 remained as an independent prognostic factor for disease-free and overall survival. 2DG decreased the UBC cell's viability, proliferation, migration, and invasion; the inhibition of cell cycle progression and apoptosis occurrence was also verified. A significant reduction in tumour growth and blood vessel formation upon 2DG treatment was observed in the chick chorioallantoic membrane assay. 2DG potentiated the cisplatin-induced inhibition of cell viability in a cisplatin-resistant subline. This study highlights HK2 as a prognostic biomarker for UBC patients and demonstrates the potential benefits of using 2DG as a glycolysis inhibitor. Future studies should focus on integrating 2DG into chemotherapy design, as an attempt to overcome cisplatin resistance.

Prognosis and immune infiltration analysis of endoplasmic reticulum stress-related genes in bladder urothelial carcinoma

Background: Abnormal activation of endoplasmic reticulum (ER) stress sensors and their downstream signalling pathways is a key regulator of tumour growth, tumour metastasis and the response to chemotherapy, targeted therapy and immunotherapy. However, the study of ER stress on the immune microenvironment of bladder urothelial carcinoma (BLCA) is still insufficient.

Methods: Firstly, 23 ER stress genes were selected to analyse their expression differences and prognostic value in BLCA based on the existing BLCA genome atlas data. According to the expression level of ER stress-related genes in BLCA, two independent clusters were identified using consensus cluster analysis. Subsequently, the correlation between these two clusters in terms of the immune microenvironment and their prognostic value was analysed. Finally, we analysed the prognostic value of the key ER stress gene HSP90B1 in BLCA and its corresponding mechanism that affects the immune microenvironment.

Results: Consensus clustering showed a worse prognosis and higher expression of immunoassay site-related genes (HAVCR2, PDCD1, CTLA4, CD274, LAG3, TIGIT and PDCD1LG2) in cluster 1 compared with cluster 2. Additionally, both TIMER and CIBERSORT algorithms showed that the expression of immune infiltrating cells in cluster 1 was significantly higher than that in cluster 2. Subsequently, HSP90B1 was identified as a key ER stress gene in BLCA, and its high expression indicated poor prognosis and was closely related to PD1. We also analysed the correlation between HSP90B1 expression and immune-infiltrating cell related biomarkers, which showed positive results. Finally, we verified the prognostic value of HSP90B1 in BLCA using an immunohistochemical assay in a tissue microarray of 100 patients with BLCA, validating the potential of HSP90B1 as a prognostic biomarker in patients with BLCA.

Conclusion: Our work reveals that ER stress genes play a crucial role in the BLCA immunological milieu, and HSP90B1 is a potential prognostic biomarker and therapeutic target for cancer immunotherapy.

Preoperative White Blood Cell-Related Indicators Can Predict the Prognosis of Patients with Transurethral Resection of Bladder Cancer

Introduction

Numerous studies, including bladder cancer (BLCA), have confirmed the relationship between conventional systemic inflammatory biomarkers and the prognosis of tumors. Leukocytes, as the most common factor in inflammatory indicators, have been reported to predict prognosis in other tumors. However, we have not seen this research in BLCA. Therefore, we aim to find new blood markers to predict the prognosis of patients with transurethral resection of bladder tumor (TURBT).

Methods

Two cohorts from the two different hospitals were used for the specific study. The best cutoff values of leukocytes-related indicators were determined according to the ROC curve. Univariate and multivariate Cox regression analysis were used to explore the impact of indicators and clinical features on prognosis for patients with TURBT. The KM curve was used to show the impact of indicators on the prognosis. According to the consequence of multivariate method, a risk model was established to evaluate the prognosis of patients with bladder cancer.

Results

The white blood cell-to-lymphocyte ratio (WLR), the white blood cell-to-hemoglobin ratio (WHR), the white blood cell-to-neutrophil ratio (WNR), the white blood cell-to-monocyte ratio (WMR) and the white blood cell-to-erythrocyte ratio (WRR) are related to the prognosis of BLCA. The new risk model consisted of WHR, WMR and platelet-to-lymphocyte ratio (PLR), and patients with TURBT in the high-risk group had a worse prognosis.

Conclusions

Leukocyte-related preoperative indicators could predict the prognosis of the patients with TURBT and provided some guidance for clinical workers.

Overexpression of Pyruvate Dehydrogenase Kinase-3 Predicts Poor Prognosis in Urothelial Carcinoma

Background

The mitochondrial pyruvate dehydrogenase complex (PDC) link glycolysis to the tricarboxylic acid cycle by decarboxylating pyruvate to acetyl coenzyme A irreversibly. Cancer cells are characterized by a shift in cellular metabolism from mitochondrial respiration to glycolysis. PDC activity inhibition mediated by phosphorylation via pyruvate dehydrogenase kinase (PDK) has been linked to cancer. However, the clinical significance of PDKs in urothelial cancer prognosis is not clear. We investigated the role and prognostic value of PDK3 expression in patients with upper urinary tract urothelial carcinoma (UTUC) and urinary bladder urothelial carcinoma (UBUC).

Patients and Methods

We retrospectively analyzed clinical data and pathological features. Formalin-fixed urothelial carcinoma (UC) tissues were collected and embedded in paraffin. The correlation of PDK3 expression with clinical characteristics, pathological findings and patient outcomes, including metastasis-free survival (MFS) and disease-specific survival (DSS) were analyzed by Pearson’s chi-square test, Kaplan–Meier analysis, and the multivariate Cox proportional hazards model.

Results

Data from 295 patients with UBUC and 340 patients with UTUC were evaluated. High PDK3 expression significantly correlated with several pathologic variables such as high T stage, lymph node metastases, high tumor grade, vascular invasion, and high mitotic rate (all P < 0.001). High PDK3 expression was associated with poor disease-specific survival (DSS) (P < 0.0001) and metastatic free survival (MFS) (P < 0.0001) in a Kaplan–Meier analysis. Additionally, multivariate analysis demonstrated increased PDK3 expression is a significant predictive risk factor for DSS [hazard ratio (HR) in UBUC, 2.79, P = 0.009; in UTUC, 2.561, P = 0.03] and MFS (HR in UBUC, 1.907, P = 0.024; in UTUC, 1.793, P = 0.044). The gene co-expression analysis showed abundant PDK3 co-upregulated genes were involved in the processes of DNA replication and repair through the Gene Ontology classification system.

Conclusion

High PDK3 expression has been linked to negative pathologic characteristics and poor oncological outcomes, suggesting that it could be used as a predictive biomarker for UC. PDK3 mRNA levels and its co-upregulated genes were strongly associated with DNA replication and repair. These results suggest that PDK3 may play a key role in tumor proliferation and development.

LncRNA SOX2-OT/miR-30d-5p/PDK1 Regulates PD-L1 Checkpoint Through the mTOR Signaling Pathway to Promote Non-small Cell Lung Cancer Progression and Immune Escape

Non-small cell lung cancer (NSCLC) is the most common type of lung cancer. Currently, treatment methods generally cause poor prognosis. Therefore, in order to seek new treatment options, we explored the internal mechanism of NSCLC. Firstly, the SOX2-OT/miR-30d-5p/PDK1 axis regulated by lncRNA SOX2-OT was predicted by bioinformatics methods, and the expression of SOX2-OT, miR-30d-5p, and PDK1 mRNA in cells were detected by qRT-PCR while PDK1 protein expression was detected by western blot. The results expressed that in NSCLC, SOX2-OT, and PDK1 were notably overexpressed while miR-30d-5p was markedly under-expressed. The interaction between them was verified by dual-luciferase reporter and RNA binding protein immunoprecipitation assays. Subsequently, through CCK8, scratch healing, cell invasion and flow cytometry assays, we revealed that inhibiting the expression of SOX2-OT could inhibit the proliferation, migration and invasion of NSCLC cells and promote cell apoptosis; while simultaneous overexpression of PDK1 or inhibition of miR-30d-5p expression could reverse the inhibitory effect of SOX2-OT silence-mediated malignant progression of NSCLC cells. Then, the combined application of overexpressed PDK1 and rapamycin verified that PDK1 could regulate the expression of PD-L1 in NSCLC cells through the mTOR signaling pathway. Co-culture of CD8⁺ T cells verified that silencing SOX2-OT could inhibit the apoptosis of CD8⁺ T cells through miR-30d-5p/PDK1. Finally, tumor formation assay in animals confirmed that overexpression of SOX2-OT could promote the growth of NSCLC tumor in vivo. In this study, assays in vitro and in vivo were conducted to elucidate the mechanism by which SOX2-OT/miR-30d-5p/PDK1 drives PD-L1 through the mTOR signaling pathway to promote the malignant progression and immune escape of NSCLC.

Correlations between glycolysis with clinical traits and immune function in bladder urothelial carcinoma

BACKGROUND

Glycolysis was a representative hallmark in the tumor microenvironment (TME), and we aimed to explore the correlations between glycolysis with immune activity and clinical traits in bladder urothelial carcinoma (BLCA).

METHODS

Our study obtained glycolysis scores for each BLCA samples from TCGA by a single-sample gene set enrichment analysis (ssGSEA) algorithm, based on a glycolytic gene set. The relationship between glycolysis with prognosis, clinical characteristics, and immune function were investigated subsequently.

RESULTS

We found that enhanced glycolysis was associated with poor prognosis and metastasis in BLCA. Moreover, glycolysis had a close correlation with immune function, and enhanced glycolysis increased immune activities. In other words, glycolysis had a positive correlation with immune activities. Immune checkpoints such as IDO1, CD274, were up-regulated in high-glycolysis group as well.

CONCLUSION

We speculated that in BLCA, elevated glycolysis enhanced immune function, which caused tumor cells to overexpress immune checkpoints to evade immune surveillance. Inhibition of glycolysis might be a promising assistant for immunotherapy in bladder cancer.