Expression profiles of the genes associated with zinc homeostasis in normal and cancerous breast and prostate cells

Abstract

Zn2+ dyshomeostasis is an intriguing phenomenon in breast and prostate cancers, with breast cancer cells exhibiting higher intracellular Zn2+ level compared to their corresponding normal epithelial cells, in contrast to the low Zn2+ level in prostate cancer cells. In order to gain molecular insights into the zinc homeostasis of breast and prostate cancer cells, this study profiled the expression of 28 genes, including 14 zinc importer genes (SLC39A1-14) that encode Zrt/Irt-like proteins 1-14 to transport Zn2+ into the cytoplasm, 10 zinc exporter genes (SLC30A1-10) which encode Zn2+ transporters 1-10 to transport Zn2+ out of the cytoplasm, and 4 metallothionein genes (MT1B, MT1F, MT1X, MT2A) in breast (MCF10A, MCF-7, MDA-MB-231) and prostate (RWPE-1, PC3, DU145) cell lines in response to extracellular zinc exposures at a mild cytotoxic dosage and a benign dosage. The RNA samples were prepared at 0 min (T0), 30 min (T30), and 120 min (T120) in a time course with or without zinc exposure, which were used for profiling the baseline and dynamic gene expression. The up-regulation of MT genes was observed across the breast and prostate cancer cell lines. The expression landscape of SLC39A and SLC30A was revealed by the quantitative reverse transcription polymerase chain reaction data of this study, which sheds light on the divergence of intracellular Zn2+ levels for breast and prostate cancer cells. Taken together, the findings are valuable in unraveling the molecular intricacy of zinc homeostasis in breast and prostate cancer cells.