Breast cancer molecular subtypes and the metastatic microenvironment: Review of literature

Abstract

Breast Cancer is a major public health concern worldwide. Breast cancer is the most common form of cancer and second leading cause of cancer death in women, with >90% of deaths resulting from metastasis. Clinically, human breast cancers are classified into distinct molecular subtypes (luminal A/B, Her2-positive, and triple-negative [TN]) which exhibit organ-specific patterns of metastasis. The lung is one of the most common sites of metastasis in patients with aggressive triple-negative (TN) disease, while less aggressive luminal A/B cancers most often metastasize to bone. Experimentally, it has been suggested that the presence of a primary tumor may serve to induce a "pre-metastatic niche" in the lung in order to make it more hospitable for metastasizing breast cancer cells. This review integrates how the cellular and molecular components of the metastatic niche evolve in the context of molecular subtype. Understanding the cancer-induced components of the metastatic niche will develop opportunities for improved clinical management and new therapeutic strategies.

What is beyond LncRNAs in breast cancer: A special focus on colon cancer-associated Transcript-1 (CCAT-1)

“…TNBC can be subdivided into 6 distinct molecular subtypes including, basal-like 1 (BL1), basal-like 2 (BL2), immunomodulatory (IM), mesenchymal (M), mesenchymal stem like (MSL) and luminal androgen receptor (LAR) [ 74 ]. Despite the profound advances in the early detection and precise management of BC over the past decades, BC is still liable to very high risks of recurrence, metastasis and treatment resistance [ 75 , 76 ].…”