Related Experiment Video
Updated: Aug 8, 2026
An Orthotopic Bladder Cancer Model for Gene Delivery Studies
Published on: December 2, 2013
Variable levels of bcl-2, bcl-x and bax mRNA in bladder cancer progression
P Gazzaniga1, A Gradilone, I Silvestri
1Dipartimento di Medicina Sperimentale e Patologia, Universita degli Studi di Roma, 00161 Roma, Italy.
Abstract:
We investigated the expression of the anti-apoptotic genes bcl-2 and bcl-X and the pro-apoptotic gene bax in bladder tumors and normal samples from urinary bladder, using RT-PCR analysis. Bcl-2 mRNA was not detected in any of the normal samples, while it was found expressed in 66% of the low stage tumors and in 100% of the high stage tumors. Bax expression had an inverse progress, being present in 62% of the normal tissues examined, in 16% of the low stage tumors and in 14% of the high stage. Bcl-X gene expression was quite variable among all samples (37% in normal tissues, 50% in the low stage tumors and 14% in the high stage). bcl-X mRNA was only found in the isoform bcl-XL, with anti-apoptotic functions, whereas no sample expressed the isoform bcl-XS, which is known to suppress bcl-2 functions. Most samples expressing bcl-2 did not express bcl-X, and vice versa. These results, besides confirming the potential role of these genes in the pathogenesis of low stage bladder cancer strengthen the hypothesis concerning their possible interaction in the progression of disease.
Insights
The anti-apoptotic gene bcl-2 and pro-apoptotic gene bax show altered expression in bladder tumors. Their differing roles suggest involvement in bladder cancer development and progression.
Area of Science:
- Oncology
- Molecular Biology
- Genetics
Background:
- Apoptosis plays a critical role in cancer development.
- Dysregulation of apoptosis is a hallmark of cancer, including bladder cancer.
- Specific genes like bcl-2, bcl-X, and bax are key regulators of apoptosis.
Purpose of the Study:
- To investigate the expression patterns of anti-apoptotic genes (bcl-2, bcl-X) and a pro-apoptotic gene (bax) in bladder tumors.
- To correlate gene expression with tumor stage in urinary bladder cancer.
- To explore the potential interaction between these apoptosis-regulating genes in bladder cancer pathogenesis.
Main Methods:
- Gene expression analysis using Reverse Transcription Polymerase Chain Reaction (RT-PCR).
- Quantification of mRNA levels for bcl-2, bcl-X, and bax in normal bladder tissues and bladder tumors.
- Analysis of bcl-X isoforms (bcl-XL and bcl-XS) expression.
Main Results:
- Bcl-2 mRNA was absent in normal tissues but present in 66% of low-stage and 100% of high-stage bladder tumors.
- Bax expression decreased from 62% in normal tissues to 16% in low-stage and 14% in high-stage tumors.
- Bcl-X expression was variable (37% normal, 50% low-stage, 14% high-stage), with only the anti-apoptotic bcl-XL isoform detected.
Conclusions:
- The differential expression of bcl-2 and bax suggests their involvement in the early stages of bladder cancer.
- The observed inverse relationship between bcl-2 and bcl-X expression supports their potential interaction in disease progression.
- These findings highlight the role of apoptosis regulators in bladder cancer pathogenesis and progression.
More Related Videos
Related Concept Videos
02:07Tumor Progression
Colon cancer is one of the best-documented examples of tumor progression. Early mutation in the APC gene in colon cells causes a small growth on the colon wall called a polyp. With time, this polyp grows into a benign, pre-cancerous tumor. Further...
01:31The Intrinsic Apoptotic Pathway