Profiling energy metabolism in normal bladder tissue and non-muscle-invasive bladder cancer cases of different histological grades

Abstract

Bladder cancer (BC) stands as the second most common urinary tract malignancy. Recent years have witnessed a growing interest in investigating energy metabolism to help with better understanding the energy sources harnessed by tumor cells. The aims of the present study are to feature and compare cell energy metabolism profiles among different histological grades of non-muscle-invasive BC (NMIBC) by adjusting their bioenergetic cellular indexes based on the specific tumor types. Forty urinary bladder tissue samples from patients both with and without a diagnosis of urothelial lesions were collected. Subsequently, samples were categorized into four groups comprising ten samples each, namely: normal (no urothelial lesions) group, low-grade pTa group, high-grade pTa group, and high-grade pT1 group. These tissue samples were examined by means of immunohistochemistry and Western blotting to assess proteins involved in cell energy metabolism. Based on the current findings, the normal and low-grade pTa groups presented clear preference for the oxidative phosphorylation pathway; consequently, they recorded high bioenergetic cellular index. On the other hand, both the high-grade pTa and pT1 groups presented proclivity towards the glycolytic pathway. These observations, mainly those associated with the bioenergetic cellular index, hold promising clinical relevance in the management of BC. Given the often aggressive and potentially debilitating nature of treatments applied to this neoplasia type, the current study offers invaluable insights on this topic and emphasizes changes in the bioenergetic cellular index at different NMIBC grades, which could serve as potential markers for both the diagnosis and prognosis of NMIBC patients.