The features of tumor niche cell composition in invasive breast ductal carcinoma of no special type

Breast cancer is the most common cancer and the leading cause of cancer death in woman of childbearing age. Tumor progression depends on the character of stromal-parenchymal interactions. Tumor microenvironment exerts a key influence on tumor progression. Tumor niche is an important element of the tumor microenvironment. According to existing ideas, tumor niche consists on immune cells and bone marrow progenitor cells. The present study describes the parameters of tumor niche in invasive breast carcinoma of no special type (IC-NST), associated with lymph node metastases. The purpose of the study was to investigate the features of tumor niche cell composition in IC-NST. Material and Methods. The study included 128 patients with IC-NST (T1-3N0-3M0), who underwent total mastectomy or partial mastectomy with axillary lymph node dissection. The age of the patients ranged from 29 to 90. Histological examination of surgical specimens was carried out in accordance with standard methods. Suspensions of fresh frozen tumor surgical specimens were prepared for the hematopoetic progenitor cells identification. The antibodies against CD34, CD133, CD90, CD11b, CD45, and CD202 were applied. Results. The study showed that the total number of hematopoietic stem and progenitor cells and macrophage progenitor cells in an amount exceeding 1.24 cells per 100 tumor cells was associated with the risk of developing lymph node metastases and large tumor size. Conclusion. The results obtained may be useful for understanding the role of tumor niche in tumor growth and lymph node metastasis of IC-NST.