High expression of miR-21 in tumor stroma correlates with increased cancer cell proliferation in human breast cancer

作者：Rask Lene^*; Balslev Eva; Jorgensen Stine; Eriksen Jens; Flyger Henrik; Moller Soren; Hogdall Estrid; Litman Thomas; Nielsen Boye Schnack

来源：Acta Pathologica, Microbiologica et Immunologica Scandinavica, 2011, 119(10): 663-673.

DOI：10.1111/j.1600-0463.2011.02782.x

• MicroRNA-21
• breast cancer
• in situ hybridization
• p53
• Ki-67

Rask L, Balslev E, Jorgensen S, Eriksen J, Flyger H, Moller S, Hogdall E, Litman T, Nielsen BS. High expression of miR-21 in tumor stroma correlates with increased cancer cell proliferation in human breast cancer. APMIS 2011; 119: 663-73.
Low-risk and high-risk breast cancer patients are stratified primarily according to their lymph node (LN) status and grading. However, some low-risk patients relapse, and some high-risk patients have a favorable clinical outcome, implying a need for better prognostic and predictive tests. Micro RNAs are often aberrantly expressed in cancer and microRNA-21 is upregulated in a variety of cancers, including breast cancer. High miR-21 levels have been associated with poor prognosis. To determine the cellular localization of miR-21 and to compare its expression levels with histopathological features, we performed in situ hybridization and semi-quantitative assessment of the miR-21 signal on 12 LN negative grade I (assumed low risk), and 12 LN positive grade II (high risk) breast cancers. miR-21 was predominantly seen in cancer associated fibroblast-like cells, with no difference in expression levels between grade I and grade II carcinomas. Immunohistochemical scoring of the prognostic proliferation marker Ki-67 and tumor suppressor p53 showed that the miR-21 expression levels significantly correlated with the Ki-67 score (p = 0.043), whereas no correlation between p53 and miR-21 was found. Our results indicate that miR-21 may contribute to improve clinical stratification according to growth rate and facilitate tailored treatment of breast cancer patients.

• 出版日期2011-10