Distribution of cancer stem cells in ductal invasive carcinoma of breast (review).

Abstract

Despite advances in detection and treatment of breast cancer, mortality from this disease remains high. According to contemporary point of view the reason for this lies in fact, that in addition to intertumor heterogeneity, there is also a high degree of intratumor diversity in cancer cell population. For most cancers it is less clear which cells within the tumor clone possess tumor-initiating cell function. During studying oncogenesis and maligniяation processes a pool of cancer cells with stem characteristics - cancer stem cells (CSC) was identified. Indeed, the specifications of them let us conclude, that exactly these cells comprise the leading substrate for cancer initiation and self-renewal. Breast carcinomas have been reported to contain a subpopulation of CD44(+)/CD24(-)/low cancer cells, which are capable of generating tumors even when implanted in very low numbers. Exactly these cells are considered to be CSCs in different subtypes of breast cancer and cancers with CD44(+)/CD24(-)/low phenotype are confirmed to have a poor prognosis (but some controversies remain concerning this issue). The aim of the review was to assess the current literature published on the breast cancer stem cells. There are not so many studies, revealing the diversity of cancer stem cells in different types, different sizes and different grade of breast cancers. CSC distribution in breast cancer with lymph node involvement, metastasizing and chemoresistant cases, existence of circulating tumor cells in not studied precisely. So the concept of cancer stem cells in breast cancer is still a topic for discussions. This can bring light to a better understanding of the pathological process in breast cancer and ways to target it.