Abstract
BACKGROUND: Social factors in the patient macroenvironment have been shown to influence molecular events in the tumor microenvironment and thereby influence cancer progression. However, biomarkers providing a window into the longitudinal effects of biobehavioral factors on tumor biology over time are lacking. Exosome analysis is a novel strategy for in vivo monitoring of dynamic changes in tumor cells. This study examined exosomal profiles from patients with low or high levels of social support for epithelial-mesenchymal transition (EMT) polarization and gene expression related to inflammation and β-adrenergic signaling. METHODS: Exosomes were isolated from plasma sampled from a series of 40 women before primary surgical resection of advanced-stage, high-grade ovarian carcinoma. Samples were selected for analysis on the basis of extremes of low and high levels of social support. After exosomal isolation and RNA extraction, a microarray analysis of the transcriptome was performed. RESULTS: Primary analyses identified significant upregulation of 67 mesenchymal-characteristic gene transcripts and downregulation of 63 epithelial-characteristic transcripts in patients with low social support; this demonstrated increased EMT polarization (P = .0002). Secondary analyses using promoter sequence bioinformatics supported a priori hypotheses linking low social support to 1) increased activity of cyclic adenosine monophosphate response element binding protein (CREB)/activating transcription factor (ATF) family transcription factors that mediate the β-adrenergic response to catecholamines via the cyclic adenosine monophosphate/protein kinase A signaling pathway (mean fold change for CREB: 2.24 ± 0.65; P = .0019; mean fold change for ATF: 2.00 ± 0.55; P = .0049) and 2) increased activity of the proinflammatory nuclear factor κB/Rel family of transcription factors (mean fold change: 2.10 ± 0.70; P = .0109). CONCLUSIONS: These findings suggest the possibility of leveraging exosomes as a noninvasive assessment of biobehavioral factors to help to direct personalized treatment approaches. Cancer 2018;124:580-6. © 2017 American Cancer Society.