Molecular Biology, Genetic, and Epigenetics of Bladder Tumor Publisher



Sh Inanloo Seyed HASSAN ; Smk Aghamir Seyed Mohammad KAZEM ; Ra Arabzadeh Bahri Razman ARABAZADEH ; Ha Azodian Ghajar Helia AZODIAN ; B Karimian BABAK
Source: Published:2024

Abstract

The bladder is a hollow organ that stores urine until the urination. Bladder cancer is a disease when there are some specific cells in the bladder with uncontrolled proliferation, which is the 14th cause of death due to cancer worldwide. Also, it is the fourth most common type of cancer among males and the ninth most common cancer among females. Tumors of the bladder are divided into two different groups based on histopathological and clinical aspects, including muscle-invasive bladder cancer (MIBC) and non-MIBC (NMIBC). Based on histopathological aspects, bladder cancer is divided into three subgroups, including transitional cell carcinoma (TCC), squamous cell carcinoma, and adenocarcinoma. The most common type of bladder cancer is TCC, which is responsible for 90% of cases. Bladder cancer is not hereditary and is mainly due to somatic mutations during the time in bladder cells (1). Bladder cancer can lead to hematuria, dysuria, or frequent urination. Multiple risk factors are related to bladder cancer, such as smoking, exposure to toxic materials and industrial toxic gas, cystitis due to microbial infections, schistosomiasis of the bladder, steroidal hormones, genetic factors, socioeconomic status, and prolonged consumption of polluted water with chlorine or arsenic, and side effects of some medications. The diagnosis of bladder cancer is based on simultaneous evaluation of urine markers, urine cytology, and cystoscopy. The cystoscopy is an invasive procedure with the risk of trauma and infection; however, the urine cytology is a classic and noninvasive way for the diagnosis of bladder cancer, which is considered the gold standard. The treatment of bladder cancer includes radiotherapy, chemotherapy, resection of the tumor, or radical cystectomy, which differs based on the invasion of the tumor. It is assumed that changes and damages to the DNA and multiple genetic mutations are responsible for the development of bladder cancer. Genetic mutations in some genes, such as TSC1, TP53, HRAS, RB1, or FGFR3, can lead to accelerated tumor formation. These genes play important roles in the regulation of cell proliferation. Changes in chromosome 9 are mostly the underlying cause of bladder cancer, which can be partial or total deletion of chromosome 9. In addition, a genetic mutation in chromosome 22 can be related to bladder cancer. However, most of the genetic changes in bladder tissue are formed during the lifetime of the patients (2). © 2024 Elsevier B.V., All rights reserved.