Expression of Telomerase Reverse Transcriptase during the Malignant Transformation of Cadmium-Induced Cells

Min Wang, Yixiong Lei

School of Public Health, Guangzhou Medical University, Guangzhou, China.

DOI: 10.4236/gep.2014.22018                

Abstract

The objective of the present study was to investigate human telomerase reverse transcriptase (hTERT) mRNA and protein expressions during the cadmium chloride-induced malignant transformation of human bronchial epithelial (16HBE) cells. Fluorescence quantitative PCR (FQ-PCR) and Western blot analyses were performed to detect the hTERT mRNA and protein expressions in normal 16HBE cells, cadmium chloride-transformed 16HBE cells, and tumorigenic cells from nude mice inoculated with cadmium chloride-transformed 16HBE cells. Under the inner standard of GAPDH, the hTERT mRNA expression was significantly higher at different stages of malignant transformation (cadmium chloride-transformed 16HBE cells at passages 15 and 35 and tumorigenic cells from nude mice) than in normal 16HBE cells, and increased with the development of malignancy (P < 0.01). In addition, hTERT protein expression increased with the development of malignancy. These findings demonstrate that hTERT expression is related to cadmium chlorideinduced malignant transformation. Cadmium chloride-induced malignant transformation is involved in changes in the hTERT activity, and might be an early event in cadmium chloride-induced malignant transformation.

Keywords

Cadmium Chloride; Human Bronchial Epithelial Cells; Malignant Transformation; Telomerase Reverse Transcriptase

Conflicts of Interest

The authors declare no conflicts of interest.

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