Genetic instability in urinary bladder cancer: An evolving hallmark

Area of Science:

• Oncology
• Genetics
• Molecular Biology

Background:

• Bladder cancer presents a significant healthcare challenge, necessitating early diagnosis for effective treatment.
• Genetic instability, predominantly at the chromosomal level, is a critical early event in bladder cancer pathogenesis.
• Understanding the deoxyribonucleic acid (DNA) mismatch repair (MMR) system is crucial for elucidating cancer development mechanisms.

Purpose of the Study:

• To review the latest literature on genetic instability in urinary bladder cancer.
• To highlight the role of microsatellite and chromosomal instability as prognostic markers.
• To categorize bladder cancers based on their genetic instability profiles.

Main Methods:

• Literature review of recent studies on genetic instability in bladder cancer.
• Analysis of genetic instability markers, including microsatellite instability (MSI) and chromosomal instability (CIN).
• Examination of DNA mismatch repair (MMR) gene defects and chromosomal alterations.

Main Results:

• Genetic instability is a hallmark of bladder cancer, often manifesting at the chromosomal level.
• Microsatellite instability arises from defects in DNA MMR genes (e.g., MLH1, MSH2).
• Specific chromosomal alterations, such as deletions on chromosomes 3, 8, 9, 11, 13, and 17, are frequently observed.

Conclusions:

• Genetic instability, encompassing both microsatellite and chromosomal alterations, is pivotal in bladder cancer development and progression.
• Microsatellite and chromosomal instability markers show promise for bladder cancer screening and prognosis.
• Distinguishing between chromosomal and nucleotide level instability provides insight into bladder cancer heterogeneity.