Open AccessDifferential expression of Oct3/4 in human breast cancer and normal tissues
Author(s) -
FengQi Zhao,
Yogi Misra,
Da-Biao Li,
Marilyn P. Wadsworth,
David N. Krag,
Donald L. Weaver,
Joseph Tessitore,
Dawei Li,
Zhiyong Guo,
Qing Tian,
Katie Buss
Publication year - 2018
Publication title -
international journal of oncology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.405
H-Index - 122
ISSN - 1019-6439
DOI - 10.3892/ijo.2018.4341
Subject(s) - biology , oncogene , breast cancer , cancer research , cancer , immunohistochemistry , pathology , microbiology and biotechnology , cell cycle , genetics , medicine , immunology
Oct3/4, a transcription factor specifically expressed in mammalian totipotent embryonic stem and germ cells, has a critical role in the regulation and maintenance of pluripotency and self-renewal. However, reactivation of Oct3/4 expression is observed in several human breast cancer cell lines, but not in non‑malignant cells. To examine Oct3/4 expression in human primary breast carcinomas and normal breast tissues, we obtained breast tumor tissues from 28 patients and normal breast tissues from 9 women. According to quantitative polymerase chain reaction, all of the tumor tissues, irrespective of tumor type or clinicopathological status, expressed Oct3/4 mRNA at 10- to 100- fold higher levels than that in the normal breast tissues. Expression of the Oct3/4 protein in tumors was confirmed by western blot analysis and immunofluorescent staining. Additionally, rapid amplification of cDNA ends and DNA sequencing revealed expression of multiple Oct4 gene transcripts from chromosome 6 (POU5F1) in normal breast tissues and the non‑malignant breast epithelial cell line MCF‑10A; by contrast, the breast tumors and malignant breast cancer cell line MCF‑7 predominantly expressed transcripts of an Oct4-like gene (POU5F1B) from chromosome 8, which was termed Oct3 in the current study. The deduced amino acid sequences of full-length Oct3 and Oct4 are 96% identical. The findings of the current study indicated that Oct3, rather than Oct4, may serve as a novel clinical marker and a potential target for gene-specific therapy of breast cancer.