Analysis of PDLIM4 Expression in Different Subtypes of Breast Cancer

Abstract

PDLIM4 is an adapter protein which is frequently silenced in different types of cancer, and is eventually induced in the event of phenotypic reversion of cancer cells. Little is known about specific mechanisms that underly involvement of PDLIM4 in the processes of malignant transformation and reversion; several data suggest that PDLIM4 could function as a regulator of c-Src tyrosine kinase activity, other observations indicate that its participation is not mandatory for c-Src regulation. In this study we explored PDLIM4 role as a possible indicator of molecular subtype of breast cancer. We performed RNA sequencing on the panel of breast cancer cell lines grouped by PDLIM4 status and compared their expression profiles with those of different breat cancer subtypes, and observed a correlation between PDLIM4 status and claudin-low phenotype, which may indicate involvement of PDLIM4 in distinct pathologic pathways that lead to malignant transformation of breast epithelium.

Studying Interrelation of PDLIM4 with the Model of CD74-Mediated Development of Breast Cancer

“…The increased expression of CD74 is associated with active metastasis and negative forecast of breast tumors development (Leth-Larsen et al, 2010;Greenwood et al, 2012;Tian et al, 2012). The previous data about studying correlation of violation of PDLIM4 expression in cells of the tumors that belong to various subtypes of BC indicates that hyperexpression of PDLIM4 is most characteristic for cells of claudindeficient subtype of the triple negative BC type (Kravchenko et al, 2015). According to this data, it seems rather interesting to assess direct correlation between PDLIM4 expression and CD74, which was also offered as a diagnostic marker of triple negative BC type (Tian et al, 2012).…”

“…Even within separate subtypes of BC, it is possible to distinguish the lines that are PDLIM4-positive and PDLIM4-negative (Kravchenko et al, 2015;Lawrence et al, 2015). These results allow to assume the existence of an alternative molecular mechanisms of tumor development, which are associated with suppression or overexpression of PDLIM4, which indicates PDLIM4's ability to act both as an oncosuppressor and an oncogene, depending on the type of the tumor.…”