The ability to induce multiple apoptotic regressions of an androgen-dependent tumor cell population by repeated cycles of androgen withdrawal and replacement may be advantageous in therapeutic strategies aimed at delaying or preventing tumor progression. With greater insight into factors that either
Paradoxical role of apoptosis in tumor progression
✍ Scribed by Katerina V. Gurova; Andrei V. Gudkov
- Publisher
- John Wiley and Sons
- Year
- 2002
- Tongue
- English
- Weight
- 255 KB
- Volume
- 88
- Category
- Article
- ISSN
- 0730-2312
No coin nor oath required. For personal study only.
✦ Synopsis
Abstract
Tumors frequently acquire resistance to apoptosis that is expected to contribute to malignant phenotype and reduce sensitivity to treatment. In fact, inactivation of p53 tumor suppressor gene resulting in suppression of apoptosis serves as a negative prognostic marker. Surprisingly, expression of a strong anti‐apoptotic protein Bcl‐2, another mechanism to avoid apoptosis, was found to be associated with a favorable prognosis. This paradoxical anti‐progressor function of Bcl‐2 has been explained in literature based on the negative effect of Bcl‐2 on cell proliferation. Here, by analyzing accumulated experimental and clinical data, we provide evidence supporting another hypothesis that defines apoptosis as an accelerator of tumor progression. The mechanism of anti‐progressor function of Bcl‐2 is based on creation of tumors that maintain control of genomic stability by eliminating selective advantages for the cells that acquire resistance to apoptosis through loss of p53. Thus, inhibition of apoptosis does not lead to loss of genomic stability and creates tumor environment that no longer supports further tumor progression and inhibitors of apoptosis can be considered as factors suppressing tumor progression. © 2002 Wiley‐Liss, Inc.
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