CCR5 activation and endocytosis in circulating tumor-derived cells isolated from the blood of breast cancer patients provide information about clinical outcome

Abstract

Background CCR5 is a motility chemokine receptor implicated in tumor progression, whose activation and subsequent endocytosis may identify highly aggressive breast cancer cell subtypes likely to spread into the circulatory system. Methods The MDA-MB-231 cell line was used to model and visualize CCR5 activation by stimulation with RANTES, in an effort to quantify CCR5 endocytosis from the cell surface to the perinuclear space. CCR5 expression was then examined in tumor-associated cells (TACs), consisting of circulating tumor cells and circulating stromal cells, isolated from the peripheral blood of 54 metastatic breast cancer (mBC) patients to evaluate these CCR5 pooling patterns as they relate to progression and survival over 2 years. Results In MB231 experiments, it was observed that CCR5 formed ~ 1 micron clusters identified as “CCR5 pools” on the surface of the cell, which in the presence of RANTES were endocytosed and translocated to the cell cytoplasm. When TACs from patients were analyzed, CCR5 pools were observed on the cell surface and translocating to the nuclear area, with CCR5 also having a positive statistical correlation between increased numbers of TACs and increased CCR5 pools on the cells. Further, it was determined that patients with very high numbers of CCR5 (> 10 CCR5 pools), specifically in the circulating stromal cells, were associated with worse progression-free survival (hazard ratio = 4.5, p = 0.002) and worse overall survival (hazard ratio = 3.7, p = 0.014). Conclusions Using a liquid biopsy approach, we evaluated two populations of tumor-associated cells emanating from primary tumors, with data suggesting that upregulation of the motility chemokine CCR5 in TACs provides clinically relevant opportunities for treating and tracking drug targetable receptors in mBC.

Beta 2-Adrenergic Receptor in Circulating Cancer-Associated Cells Predicts for Increases in Stromal Macrophages in Circulation and Patient Survival in Metastatic Breast Cancer

“…The previous literature has described that increased adrenergic signaling in cancer can increase cancer growth [6,10,28]. Further, increases in tumor-associated macrophage activation have been suggested to increase the migration of these myeloid cells [14,29]. As such, it stands to reason that the increased B2AR signaling and activation in CAMLs may be related to the increased number in circulation.…”

Circulating Stromal Cells are Prognostic for Highly Aggressive Prostate Cancer in both the Non-Metastatic and Metastatic Settings

“…CAMLs were identi ed as 30μm-300μm in size, DAPI positive polyploid nuclei, surface markers of CD45, and a diffuse expression of cytokeratin. Apoptotic and denucleated cells were not included in our analyses [29][30][31][32][33]35,37,40,41 .…”

“…To explore previous literature 32,[35][36][37]39 on hyper-enlarged CAMLS (≥100μm) for predicting severely worse outcomes in patients, we ran analysis to investigate how these massively-engorged CAMLs relate to outcomes in PCa. First, we examined ≥100μm CAML presence among all patients, and found that 14% (n=13/90) of BL samples had the hyper-enlarged CAML subtype.…”

“…Increasing CAML size (beyond 50μm) has been implicated in solid-tumor pathogenesis and decreased patient survival across multiple of solid cancers 32,[35][36][37]39 . To examine this pattern in PCa, we compared all BL samples, nding the average max CAML size was statistically larger in patients with metastatic disease over localized PCa (78μm metastatic vs. 35μm localized, p<0.001) (Fig.…”

“…Cancer Associated Macrophage-Like cells have been identi ed as a cancer-speci c circulating cell that appears to be an independent prognostic indicator of tumor aggressiveness across multiple solid-tumor malignancies [29][30][31][32][33] . Uniquely, CAMLs are solely identi ed in human cancer patients and appear absent in healthy controls 22,[31][32][33][34][35][36] . Cytological identi cation of CAML cells is dependent on morphological features such as cell cytoplasmic diameter ≥30µm, the presence of polyploid nuclei, as well as the phenotypic expression of CD45, Cytokeratins 8, 18, 19 and DAPI 31 .…”