The study of energy metabolism in bladder cancer cells in co-culture conditions using a microfluidic chip.

OBJECTIVES: This study aimed to systematically analyze changes in mitochondrial-related protein expression in bladder cancer cells and tumor-associated fibroblasts and to investigate the characteristics of bladder cancer cell energy metabolism. METHODS: In this study, we utilized the following techniques to achieve the objectives: (1) a co-culture system of bladder tumor cells and fibroblasts was built using a microfluidic chip as a three-dimensional culture system; (2) the concentration of lactic acid in the medium from the different groups was determined using an automatic micro-plate reader; (3) a qualitative analysis of mitochondria-related protein expression was performed by immunofluorescent staining; and (4) a quantitative analysis of mitochondrial-associated protein expression was conducted via Western blot. SPSS software was utilized to analyze the data. RESULTS: (1) Determination of lactic acid concentration: The lactic acid concentration was determined to be highest in the experimental group, followed by the T24 cell control group and then the fibroblast control group. (2) Qualitative results: In the control group, the mitochondrial-related protein fluorescence intensity was higher in the fibroblasts compared with the cancer cells, and the fluorescence intensity of the fibroblasts was reduced compared with the experimental group. The mitochondrial-related protein fluorescence intensity of the cancer cells was higher in the experimental group compared with the control group, and the opposite results were obtained with the fibroblasts. (3) Quantitative results: The expression of mitochondria-related proteins was higher in fibroblasts compared with cancer cells in the control group, and the opposite results were obtained in the experimental group (P<0.05). The expression of mitochondria-related proteins was increased in cancer cells in the experimental group compared with the control group; the opposite results were observed for the fibroblasts (P<0.05). CONCLUSIONS: The energy metabolism of bladder tumor cells does not parallel the "Warburg effect" because even under sufficient oxygen conditions, cancer cells still undergo glycolysis. Bladder cancer cells also have an efficient oxidative phosphorylation process wherein cancer cells promote glycolysis in adjacent interstitial cells, thereby causing increased formation of nutritional precursors. These high-energy metabolites are transferred to adjacent tumor cells in a specified direction and enter the Krebs Cycle. Ultimately, oxidative phosphorylation increases, and sufficient ATP is produced.

A bladder cancer microenvironment simulation system based on a microfluidic co-culture model.

A tumor microenvironment may promote tumor metastasis and progression through the dynamic interplay between neoplastic cells and stromal cells. In this work, the most representative and significant stromal cells, fibroblasts, endothelial cells, and macrophages were used as vital component elements and combined with bladder cancer cells to construct a bladder cancer microenvironment simulation system. This is the first report to explore bladder cancer microenvironments based on 4 types of cells co-cultured simultaneously. This simulation system comprises perfusion equipment, matrigel channel units, a medium channel and four indirect contact culture chambers, allowing four types of cells to simultaneously interact through soluble biological factors and metabolites. With this system, bladder cancer cells (T24) with a tendency to form a 'reticular' structure under 3 dimensional culture conditions were observed in real time. The microenvironment characteristics of paracrine interactions and cell motility were successfully simulated in this system. The phenotype change process in stromal cells was successfully reproduced in this system by testing the macrophage effector molecule Arg-1. Arg-1 was highly expressed in the simulated tumor microenvironment group. To develop "precision medicine" in bladder cancer therapy, bladder cancer cells were treated with different clinical 'neo-adjuvant' chemotherapy schemes in this system, and their sensitivity differences were fully reflected. This work provides a preliminary foundation for neo-adjuvant chemotherapy in bladder cancer, a theoretical foundation for tumor microenvironment simulation and promotes individual therapy in bladder cancer patients.

Perioperative Blood Transfusion Promotes Worse Outcomes of Bladder Cancer after Radical Cystectomy: A Systematic Review and Meta-Analysis.

BACKGROUND: Multiple studies have investigated the effect of perioperative blood transfusion (PBT) for patients with radical cystectomy (RC), but the results have been inconsistent. We conducted a systematic review and meta-analysis to investigate the relationship between PBT and the clinical outcomes of RC patients. METHODS: We searched MEDLINE, EMBASE, the Cochrane library and BIOSIS previews to identify relevant literature for studies that focused on the relationship of PBT and outcomes of patients undergoing RC. A fixed or random effects model was used in this meta-analysis to calculate the pooled hazard ratio (HR) with 95% confidence intervals (CIs). RESULTS: A total of 7080 patients in 6 studies matched the selection criteria. Aggregation of the data suggested that PBT in patients who underwent RC correlated with increased all-cause mortality, cancer-specific mortality and cancer recurrence. The combined HRs were 1.19 (n = 6 studies, 95% CI: 1.11-1.27, Z = 4.71, P<0.00001), 1.17 (n = 4 studies, 95% CI: 1.06-1.30, Z = 3.06, P = 0.002), 1.14 (n = 3 studies, 95% CI: 1.03-1.27, Z = 2.50, P = 0.01), respectively. The all-cause mortality associated with PBT did not vary by the characteristics of the study, including number of study participants, follow-up period and the median blood transfusion ratio of the study. CONCLUSION: Our data showed that PBT significantly increased the risks of all-cause mortality, cancer-specific mortality and cancer recurrence in patients undergoing RC for bladder cancer.