Mesenchymal Stem Cells Derived from Human Adipose Tissues Favor Tumor Cell Growth <i>in vivo</i>

TLDR

Mesenchymal stem cells are promising for regenerative medicine, yet their therapeutic use is constrained by unclear effects on tumor growth and long‑term safety. The study sought to determine whether human adipose‑derived MSCs promote tumor growth in vivo and to assess their safety for future therapeutic applications. Researchers transplanted hASCs together with H460 or U87MG tumor cells subcutaneously or intracranially into BALB/c nude mice to observe tumor outgrowth. Co‑injection of hASCs increased tumor growth, proliferation, and viability, reduced apoptosis, and had no impact on intratumoral vessel formation, demonstrating that hASCs favor tumor growth in vivo.

Abstract

Mesenchymal stem cells (MSCs) have generated a great deal of interest in clinical situations, due principally to their potential use in regenerative medicine and tissue engineering applications. However, the therapeutic application of MSCs remains limited, unless the favorable effects of MSCs for tumor growth in vivo and the long-term safety of the clinical applications of MSCs can be understood more thoroughly. In this study, MSCs derived from human adipose tissues (hASCs) together with tumor cells were transplanted subcutaneously or intracranially into BALB/c nude mice to observe tumor outgrowth. The results indicated that hASCs with H460 or U87MG cells promoted tumor growth in nude mice. Our histopathological analyses indicated that the co-injection of tumor cells with hASCs exerted no influence on the formation of intratumoral vessels. Co-culture of tumor cells with hASCs or the addition of conditioned medium (CM) from hASCs effected an increase in the proliferation of H460 or U87MG cells. Co-injection of hASCs with tumor cells effected an increase in tumor cell viability in vivo, and also induced a reduction in apoptotic cell death. CM from hASCs inhibited hydrogen peroxide-induced cell death in H460 or U87MG cells. These findings indicated that MSCs could favor tumor growth in vivo. Thus, it is necessary to conduct a study concerning the long-term safety of this technique before MSCs can be used as therapeutic tools in regenerative medicine and tissue engineering.