The expression of hTR and hTERT in human breast cancer: correlation with clinico-pathological parameters

Abstract

BackgroundTelomerase is a ribonucleoprotein enzyme that synthesises telomeres after cell division and maintains chromosomal stability leading to cellular immortalization. Telomerase has been associated with negative prognostic indicators in some studies. The present study aims to detect any association between telomerase sub-units: hTERT and hTR and the prognostic indicators including tumour's size and grade, nodal status and patient's age.MethodsTumour samples from 46 patients with primary invasive breast cancer and 3 patients with benign tumours were collected. RT-PCR analysis was used for the detection of hTR, hTERT, and PGM1 (as a housekeeping) genes expression.ResultsThe expression of hTR and hTERT was found in 31(67.4%) and 38 (82.6%) samples respectively. We observed a significant association between hTR gene expression and younger age at diagnosis (p = 0.019) when comparing patients ≤ 40 years with those who are older than 40 years. None of the benign tumours expressed hTR gene. However, the expression of hTERT gene was revealed in 2 samples.No significant association between hTR and hTERT expression and tumour's grade, stage and nodal status was seen.ConclusionThe expression of hTR and hTERT seems to be independent of tumour's stage. hTR expression probably plays a greater role in mammary tumourogenesis in younger women (≤ 40 years) and this may have therapeutic implications in the context of hTR targeting strategies.

The diagnostic value of RNA oncomarkers in evaluation of malignant breast tumors

“…(1) Telomerase (hTER), which is present only in cells exhibiting potential for unlimited division; there is evidence for overexpression of this enzyme in breast carcinoma cells [2].…”

Telomerase Reverse Transcriptase-Promoter Mutation in Young Patients with Bladder Tumors

“…Telomerase is a ribonucleoprotein reverse transcriptase that performs telomeric DNA replication from an RNA template integrated into itself, stabilizing its length by preventing its shortening at each cell division [1,2]. The TERT gene encodes the catalytic subunit of telomerase responsible for its reverse transcriptase activity and is encoded on chromosome 5 [3,4]. The TERT gene promoter (pTERT) is a 260-base-pair (bp) region lacking a TATA box and containing binding motifs for various transcription factors, such as p21, p53, E2F, AP1, and c-Myc, whose binding to the promoter activates, to a greater or lesser extent, the transcription of the gene and thus the formation of its product, the catalytic subunit of telomerase.…”

The diagnostic value of RNA oncomarkers in evaluation of malignant breast tumors

“…Теломераза (hTERT), которая присутствует только в клетках, способных к неограниченному делению, в том числе и раковых; в литературе есть данные о сверхэкспрессии этого фермента в клетках карциномы молочной железы [2].…”