The Role of the Tumor Microenvironment in Triple-Positive Breast Cancer Progression and Therapeutic Resistance

SIMPLE SUMMARY: This is an important point of view that the development of breast carcinogenesis is not only related to the intrinsic characteristics of the cancer cells, but that it is also strongly dependent on surrounding microenvironmental factors. It is important to note that triple-positive breast cancer accounts for about 10–15% of all breast cancers, and research on the tumor microenvironment for this subtype is still limited. In this review, authors explored the relationship between critical cellular components and factors in the triple-positive breast cancer microenvironment and the inception, advancement, and therapeutic resistance of breast cancer to provide perspectives on the latest research on triple-positive breast cancer. The authors sufficiently described the state of the art and reported the fundamental concepts, allowing an easy comprehension of the intricate dynamics within tumor microenvironment in triple-positive breast cancer. ABSTRACT: Breast cancer (BRCA) is a highly heterogeneous systemic disease. It is ranked first globally in the incidence of new cancer cases and has emerged as the primary cause of cancer-related death among females. Among the distinct subtypes of BRCA, triple-positive breast cancer (TPBC) has been associated with increased metastasis and invasiveness, exhibiting greater resistance to endocrine therapy involving trastuzumab. It is now understood that invasion, metastasis, and treatment resistance associated with BRCA progression are not exclusively due to breast tumor cells but are from the intricate interplay between BRCA and its tumor microenvironment (TME). Accordingly, understanding the pathogenesis and evolution of the TPBC microenvironment demands a comprehensive approach. Moreover, addressing BRCA treatment necessitates a holistic consideration of the TME, bearing significant implications for identifying novel targets for anticancer interventions. This review expounds on the relationship between critical cellular components and factors in the TPBC microenvironment and the inception, advancement, and therapeutic resistance of breast cancer to provide perspectives on the latest research on TPBC.