Toll-like receptor 3-mediated modulation of umbilical cord mesenchymal stem cell phenotype and pancreatic cancer cell responses during coculture

Yılmaz A., Kaçaroğlu D.

TRAKYA UNIVERSITY JOURNAL OF NATURAL SCIENCES, cilt.26, sa.2, ss.1-10, 2025 (ESCI)

Özet

Mesenchymal stem cells (MSCs) are progenitor cells isolated from

various tissues and are crucial for tissue repair, immune support,

and anticancer therapies. MSC functions such as migration,

immunomodulation, and regeneration are regulated through Tolllike

receptors (TLRs). In particular, TLR3 activation enhances the

immunosuppressive and therapeutic capabilities of MSCs. This

research employed human umbilical cord-derived MSCs (UCMSCs)

and investigated the effects of TLR3 stimulation on their viability,

phenotype-associated gene expression, and during co-culture

with Panc-1 pancreatic cancer cells. UCMSCs were cultured and

characterized for mesenchymal markers by flow cytometry. TLR3-

based signaling was modulated using Poly(A:U) (an agonist) and

CU-CPT4a (an antagonist). Cell viability was assessed using the

3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide assay,

and relative gene expression was measured employing quantitative

reverse transcription polymerase chain reaction. Panc-1 cells were cocultured

with UCMSCs to evaluate TLR3-mediated effects. Data are

presented as the means ± standard error of the mean, with statistical

significance determined by analysis of variance (p ≤ 0.05). The TLR3

agonist improved cell viability, whereas the antagonist reduced it.

Additionally, both regulated the expression of CD44, CDH1, and

VIMs. When UCMSCs and Panc-1 cells were cocultured at 10:1,

TLR3 affected the expression of MSC-related genes, including CD44,

CDH1, CLDN1, VIM, ZEB1, MMP9, MMP2, TIMP1, VEGFR2,

and PLAU. Thus, TLR3-based signaling influenced the viability,

maintenance of the mesenchymal phenotype, and Panc-1 cocultureassociated

phenotype in UCMSCs. These results underscore the

crucial role of TLR3-based signaling in modulating UCMSC function and suggest its potential utility in enhancing MSC-based therapeutic

strategies. We believe that these results can help elucidate the role of

TLR3-based signaling on UCMSC functions and provide a basis for

future research.