Exosomes, cancer’s little army

Abstract

In an attempt to conceptualize the process of cancer formation, Hanahan and Weinberg [2000] have outlined six universal characteristics of tumorigenesis, and labelled them as the "hallmarks of cancer". These hallmarks include; unlimited proliferation, evading growth suppressors, resisting cell death, replicative immortality, inducing angiogenesis, initiating invasion and metastasis. Cancer cell signalling is crucial for initiating and controlling cellular pathways that are involved in these hallmarks. The intricate network of communication between cancer cells and other cancer or non-cancer cells is still being investigated, and is yet to be fully understood. Initially it was proposed that the main form of communication between cells within the tumour microenvironment are soluble growth factors, and gap junctions. Then, researchers reported another form of cell-to-cell communication, through the release of spherical particles called exosomes. It is believed that these exosomes enable communication through the transfer of active components from the releasing cell, and off-loading it into the recipient cell. As researchers continue to examine the development of the cancer hallmarks and the pathways involved, it became evident that cancer cell-derived exosomes play a major role in almost all of them. This review will examine the role played by cancer cell-derived exosomes in development of cancer.

Exocyst controls exosome biogenesis via Rab11a

“…8 Various in vitro assays have demonstrated that cancer-derived exosomes, which act as cancer's little army, promote tumor malignant biological behavior. 38 The stomach adenocarcinoma cell SGC-7901 promoted tumor cell proliferation by exosome secretion in a dose-dependent manner. 39 Exosomes secreted by human liver cancer cell HCC-LM3 significantly promoted the proliferation of liver cancer cells.…”

Aberrantly expressed Wnt5a in nurse-like cells drives resistance to Venetoclax in chronic lymphocytic leukemia

“…In the bone marrow and secondary lymphoid tissues, CLL cells engage in complex cellular and molecular interactions with non-neoplastic accessory cells in the microenvironment [ 10 – 12 ]. These interactions provide CLL cells survival, proliferation, and drug resistance.…”

The role of exosomes in cancer‐related programmed cell death

“…Exosomes produced by cancer cells are known to regulate lung cancer development by promoting epithelial‐mesenchymal transition of tumor cells, inducing angiogenesis, establishing a premetastatic microenvironment, and evading the immune system 58 . Furthermore, cancer cell exosomes have played a major role in the development of almost all cancer markers and their associated pathways by transferring active components from releasing cells to recipient cells 59 …”