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Identification of luminal breast cancers that establish a tumor-supportive macroenvironment defined by proangiogenic platelets and bone marrow-derived cells.

ABSTRACT: Breast cancer recurrence rates vary following treatment, suggesting that tumor cells disseminate early from primary sites but remain indolent indefinitely before progressing to symptomatic disease. The reasons why some indolent disseminated tumors erupt into overt disease are unknown. We discovered a novel process by which certain luminal breast cancer (LBC) cells and patient tumor specimens (LBC "instigators") establish a systemic macroenvironment that supports outgrowth of otherwise-indolent disseminated tumors ("responders"). Instigating LBCs secrete cytokines that are absorbed by platelets, which are recruited to responding tumor sites where they aid vessel formation. Instigator-activated bone marrow cells enrich responding tumor cell expression of CD24, an adhesion molecule for platelets, and provide a source of VEGF receptor 2(+) tumor vessel cells. This cascade results in growth of responder adenocarcinomas and is abolished when platelet activation is inhibited by aspirin. These findings highlight the macroenvironment as an important component of disease progression that can be exploited therapeutically.Currently, processes that mediate progression of otherwise indolent tumors are not well understood, making it difficult to accurately predict which cancer patients are likely to relapse. Our findings highlight the macroenvironment as an important component of disease progression that can be exploited to more accurately identify patients who would benefit from adjuvant therapy.

SUBMITTER: Kuznetsov HS

PROVIDER: S-EPMC3517696 | biostudies-literature | 2012 Dec

REPOSITORIES: biostudies-literature

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Identification of luminal breast cancers that establish a tumor-supportive macroenvironment defined by proangiogenic platelets and bone marrow-derived cells.

Kuznetsov Hanna S HS Marsh Timothy T Markens Beth A BA Castaño Zafira Z Greene-Colozzi April A Hay Samantha A SA Brown Victoria E VE Richardson Andrea L AL Signoretti Sabina S Battinelli Elisabeth M EM McAllister Sandra S SS

Cancer discovery 20120815 12

<h4>Unlabelled</h4>Breast cancer recurrence rates vary following treatment, suggesting that tumor cells disseminate early from primary sites but remain indolent indefinitely before progressing to symptomatic disease. The reasons why some indolent disseminated tumors erupt into overt disease are unknown. We discovered a novel process by which certain luminal breast cancer (LBC) cells and patient tumor specimens (LBC "instigators") establish a systemic macroenvironment that supports outgrowth of o ...[more]

PMID: 22896036

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Dataset Information

Identification of luminal breast cancers that establish a tumor-supportive macroenvironment defined by proangiogenic platelets and bone marrow-derived cells.

Publications

Identification of luminal breast cancers that establish a tumor-supportive macroenvironment defined by proangiogenic platelets and bone marrow-derived cells.

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