BMI1 polycomb group protein acts as a master switch for growth and death of tumor cells : regulates TCF4-transcriptional factor-induced BCL2 signaling

For advanced prostate cancer (CaP), the progression of tumors to the state of chemoresistance and paucity of knowledge about the mechanism of chemoresistance are major stumbling blocks in the management of this disease. Here, we provide compelling evidence that BMI1 polycomb group protein and a stem cell factor plays a crucial role in determining the fate of tumors vis-à-vis chemotherapy. We show that progressive increase in the levels of BMI1 occurs during the progression of CaP disease in humans. We show that BMI1-rich tumor cells are non-responsive to chemotherapy whereas BMI1-silenced tumor cells are responsive to therapy. By employing microarray, ChIP, immunoblot and Luciferase reporter assays, we identified a unique mechanism through which BMI1 rescues tumor cells from chemotherapy. We found that BMI1 regulates (i) activity of TCF4 transcriptional factor and (ii) binding of TCF4 to the promoter region of anti-apoptotic BCL2 gene. Notably, an increased TCF4 occupancy on BCL2 gene was observed in prostatic tissues exhibiting high BMI1 levels. Using tumor cells other than CaP, we also showed that regulation of TCF4-mediated BCL2 by BMI1 is universal. It is noteworthy that forced expression of BMI1 was observed to drive normal cells to hyperproliferative mode. We show that targeting BMI1 improves the outcome of docetaxel therapy in animal models bearing chemoresistant prostatic tumors. We suggest that BMI1 could be exploited as a potential molecular target for therapeutics to treat chemoresistant tumors.

Medienart:

E-Artikel

Erscheinungsjahr:

2013

Erschienen:

2013

Enthalten in:

Zur Gesamtaufnahme - volume:8

Enthalten in:

PloS one - 8(2013), 5 vom: 01., Seite e60664

Sprache:

Englisch

Beteiligte Personen:

Siddique, Hifzur Rahman [VerfasserIn]
Parray, Aijaz [VerfasserIn]
Tarapore, Rohinton S [VerfasserIn]
Wang, Lei [VerfasserIn]
Mukhtar, Hasan [VerfasserIn]
Karnes, R Jeffery [VerfasserIn]
Deng, Yibin [VerfasserIn]
Konety, Badrinath R [VerfasserIn]
Saleem, Mohammad [VerfasserIn]

Links:

Volltext

Themen:

15H5577CQD
2C323EGI97
Antineoplastic Agents
BMI1 protein, human
Basic Helix-Loop-Helix Leucine Zipper Transcription Factors
Cisplatin
Docetaxel
EC 2.3.2.27
Journal Article
Metribolone
Polycomb Repressive Complex 1
Proto-Oncogene Proteins c-bcl-2
Q20Q21Q62J
Research Support, U.S. Gov't, Non-P.H.S.
TCF4 protein, human
Taxoids
Testosterone Congeners
Transcription Factor 4
Transcription Factors

Anmerkungen:

Date Completed 17.12.2013

Date Revised 21.10.2021

published: Electronic-Print

Citation Status MEDLINE

doi:

10.1371/journal.pone.0060664

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM227472934