MicroRNA-33a levels do not correlate with the expression of its host gene SREBF2 and its isoforms in prostate cancer cell lines

Year 2018, Volume: 4 Issue: 2, 79 - 84, 04.04.2018

Ömer Faruk Karataş , Michael Ittmann

https://doi.org/10.18621/eurj.341363

Abstract

Objectives. Prostate cancer
is currently the most frequently diagnosed malignant
neoplasm and the second leading cause of cancer related
mortality in men over the age of 50 years in the developed countries. MicroRNA-33a
(miR-33a), localized within the intron 16 of SREBF2, has been reported to have tumor suppressive properties in
some cancers including prostate cancer, whereas its host gene, SREBF2, has been
shown to be elevated in prostate cancer and to act as an oncogene. Due to the
paradoxical expression of an oncogene and a tumor suppressor from a single
genetic locus, there is a need for evaluation of miR-33a and SREBF2 expression
status in prostate cancer cells to help understanding their roles in prostate
carcinogenesis. Methods. In this study, we aimed at investigating the link
between the expressions of miR-33a and its host gene SREBF2 and its isoforms in
prostate cancer cell lines using quantitative real time PCR. We evaluated the
relative expression levels with using 2^{- ΔΔCT} method and tested the
correlations of microRNA and gene expressions with Pearson’s Correlation test
using GraphPad Prism 6. Results. Our results demonstrated
variable expression levels for SREBF2 mRNA and miR-33a expression levels in
prostate cancer cell lines, with some decreased, some increased and some
unchanged. Further analysis showed a strong correlation among expressions of
SREBF2 isoforms though we could not find a significant association between
levels of SREBF2 isoforms and miR-33a expression. Conclusion. This data
suggest possible posttranscriptional regulation of miR-33a expression in
prostate cancer.

Keywords

Prostate cancer, miR-33a, SREBF2, correlation

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