Immune microenvironment in different molecular subtypes of ductal breast carcinoma.
PURPOSE
Ductal breast carcinoma as a heterogeneous disease has different molecular subtypes associated with clinical prognosis and patients' survival. The role of immune system as a consistent part of the tumor microenvironment (TME) has been documented in progression of ductal breast carcinoma. Here, we aimed to describe the important immune cells and the immune system-associated molecules in Ductal Carcinoma In situ (DCIS) and Invasive Ductal Carcinoma (IDC) with special emphasis on their associations with different molecular subtypes and patients' prognosis.


RESULTS
The immune cells have a dual role in breast cancer (BC) microenvironment depending on the molecular subtype or tumor grade. These cells with different frequencies are present in the TME of DCIS and IDC. The presence of regulatory cells including Tregs, MDSC, Th2, Th17, M2 macrophages, HLADR- T cells, and Tγδ cells is related to more immunosuppressive microenvironment, especially in ER- and TN subtypes. In contrast, NK cells, CTL, Th, and Tfh cells are associated to the anti-tumor activity. These cells are higher in ER+ BC, although in other subtypes such as TN or HER2+ are associated with a favorable prognosis.


CONCLUSION
Determining the specific immune response in each subtype could be helpful in estimating the possible behavior of the tumor cells in TME. It is important to realize that different frequencies of immune cells in BC environment likely determine the patients' prognosis and their survival in each subtype. Therefore, elucidation of the distinct immune players in TME would be helpful toward developing targeted therapies in each subtype.
['Sadeghalvad|Mona|M|', 'Mohammadi-Motlagh|Hamid-Reza|HR|', 'Rezaei|Nima|N|http://orcid.org/0000-0002-3836-1827']
D014408:Biomarkers, Tumor D001943:Breast Neoplasms D018270:Carcinoma, Ductal, Breast D002285:Carcinoma, Intraductal, Noninfiltrating D005260:Female D006801:Humans D007111:Immunity, Cellular D011379:Prognosis D059016:Tumor Microenvironment
Molecular subtypes Tumor microenvironment Immune cells Ductal carcinoma Breast cancer