Comparative Analysis Between Mesenchymal Stem Cells From Subcutaneous Adipose Tissue and Omentum in Three Types of Patients: Cancer, Morbid Obese and Healthy Control.

Objective. The aims of this study are to compare 2 origins of adipose-derived mesenchymal stem cells (MSCs) (omentum and subcutaneous) from 2 pathologies (morbid obesity and cancer) vs healthy donors. Adipose tissue has revealed to be the ideal MSC source. However, in developing adipose-derived stem cells (ASCs) for clinical use, it is important to consider the effects of different fat depots and also the effect of donor variability. Methods. We isolated and characterized the membrane markers and differentiation capacities of ASCs obtained from patients with these diseases and different origin. During the culture period, we further analysed the cells' proliferation capacity in an in vitro assay as well as their secretome. Results. Adipose-derived stem cells isolated from obese and cancer patients have mesenchymal phenotype and similar cell proliferation as ASCs derived from healthy donors, some higher in cells derived from subcutaneous fat. However, cells from these 2 types of patients do not have the same differentiation potential, especially in cancer patients from omentum, and exhibit distinct secretion of both pro-inflammatory and regulatory cytokines, which could explain the differences in use due to origin as well as pathology associated with the donor. Conclusion. Subcutaneous and omentum ASCs are slightly different; omentum generates fewer cells but with greater anti-inflammatory capacity. Adipose-derived stem cells from patients with either obesity or cancer are slightly altered, which limits their therapeutic properties.

Cimp-Positive Status is More Representative in Multiple Colorectal Cancers than in Unique Primary Colorectal Cancers.

Colorectal cancer (CRC) with CpG island methylator phenotype (CIMP) is recognized as a subgroup of CRC that shows association with particular genetic defects and patient outcomes. We analyzed CIMP status of 229 individuals with CRC using an eight-marker panel (CACNA1G, CDKN2A, CRABP1, IGF2, MLH1, NEUROG1, RUNX3 and SOCS1); CIMP-(+) tumors were defined as having ≥ 5 methylated markers. Patients were divided into individuals who developed a "unique" CRC, which were subclassified into early-onset CRC (EOCRC) and late-onset CRC (LOCRC), and patients with multiple primary CRCs subclassified into synchronous CRC (SCRC) and metachronous CRC (MCRC). We found 9 (15.2%) CIMP-(+) EOCRC patients related with the proximal colon (p = 0.008), and 19 (26.8%) CIMP-(+) LOCRC patients associated with tumor differentiation (p = 0.045), MSI status (p = 0.021) and BRAF mutation (p = 0.001). Thirty-five (64.8%) SCRC patients had at least one CIMP-(+) tumor and 20 (44.4%) MCRC patients presented their first tumor as CIMP-(+). Thirty-nine (72.2%) SCRC patients showed concordant CIMP status in their simultaneous tumors. The differences in CIMP-(+) frequency between groups may reflect the importance of taking into account several criteria for the development of multiple primary neoplasms. Additionally, the concordance between synchronous tumors suggests CIMP status is generally maintained in SCRC patients.