Transcriptional activation of hTERT in breast carcinomas by the Her2-ER81-related pathway.
Her2 and ER81 (a member of ETS family) have been suggested to cause a synergistic increase in the transcriptional activation of hTERT. Our study aimed to offer further confirmation in clinical material. We determined the mRNA levels of Her2, ER81, and hTERT, by QRT-PCR, in 43 breast carcinomas. In the specimens showing hTERT transcriptional activation, Her2 and ER81 were increased in statistically significant tumor subgroups (61% and 79% correspondingly). The 86% of specimens with both Her2 and ER81 increased expression showed hTERT transcriptional activation. Synchronous transcriptional activation of hTERT, Her2, and ER81 elevated expression was noted in 42% of the samples. In conclusion, we agree with a previous study that Her2 overexpression may increase the hTERT transcriptional activation. Our data indicate that the mechanism may involve Her2-ER81 interaction(s) and that the activation of hTERT could be mainly mediated by transcriptional activation of ER81.
Vageli
Dimitra
D
Department of Pathology, University Hospital of Larissa, Medical School of Thessaly, Larissa, Greece. vagelidim@yahoo.gr
Ioannou
Maria G
MG
Koukoulis
George K
GK
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001943:Breast Neoplasms / Q000235:genetics*; D004268:DNA-Binding Proteins / Q000235:genetics / Q000502:physiology*; D005260:Female; D020869:Gene Expression Profiling; D006801:Humans; D008875:Middle Aged; D012333:RNA, Messenger / Q000032:analysis; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000235:genetics / Q000502:physiology*; D015398:Signal Transduction / Q000502:physiology*; D019098:Telomerase / Q000235:genetics*; D014157:Transcription Factors / Q000235:genetics / Q000502:physiology*; D015533:Transcriptional Activation
D004268:DNA-Binding Proteins; D012333:RNA, Messenger; D018719:Erb-b2 Receptor Tyrosine Kinases; D019098:Telomerase; D014157:Transcription Factors; C095239:ETV1 protein, human; C508053:ERBB2 protein, human; C509186:TERT protein, human