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Title: The Role of Osteocytes in Pre-metastatic Niche Formation
Purpose of review: The formation of a pre-metastatic niche (PMN), in which primary cancer cells prime the distant site to be favorable to their engraftment and survival, may help explain the strong osteotropism observed in multiple cancers, such as breast and prostate. PMN formation, which includes extracellular matrix remodeling, increased angiogenesis and vascular permeability, enhanced bone marrow-derived cell recruitment and immune suppression, has mostly been described in soft tissues. In this review, we summarize current literature of PMN formation in bone. We also present evidence of a potential role for osteocytes to be the primary mediators of PMN development. Recent findings: Osteocytes regulate the bone microenvironment in myriad ways beyond canonical bone tissue remodeling, including changes that contribute to PMN formation. Perilacunar tissue remodeling, which has been observed in both bone and non-bone metastatic cancers, is a potential mechanism by which osteocyte-cancer cell signaling stimulates changes to the bone microenvironment. Osteocytes also protect against endothelial permeability, including that induced by cancer cells, in a loading-mediated process. Finally, osteocytes are potent regulators of cells within the bone marrow, including progenitors and immune cells, and might be involved in this aspect of PMN formation. Osteocytes should be examined for their role in PMN formation.  more » « less
Award ID(s):
2047187
PAR ID:
10494352
Author(s) / Creator(s):
;
Publisher / Repository:
SpringerLink
Date Published:
Journal Name:
Current Osteoporosis Reports
Volume:
22
Issue:
1
ISSN:
1544-1873
Page Range / eLocation ID:
105 to 114
Subject(s) / Keyword(s):
Bone metastasis Mechanical loading Microenvironment Osteocyte Pre-metastatic niche
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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