Mesenchymal stem cells (MSCs) in tumors have emerged as progenitors involved in stroma formation and metastasis of cancers, partially owing to their abilities to differentially express paracrine factors related to the proliferation and invasion of cancer cells. In this regard, increasing evidence has shown that MSCs have impacts on the malignancy of colon cancer, however, the underpinning mechanisms by which MSCs promote cancer metastasis remain elusive. To investigate the crosstalk between adipose-derived MSCs (AMSCs) isolated from adipose tissues and colon cancer cells, a co-culture transwell model of AMSCs and colon cancer cells was employed, and the activation of Wnt signaling and paracrine factors in colon cancer cells and AMSCs were measured. The results showed that AMSCs could enhance the metastatic capacity of colon cancer cells with an elevated expression of mesenchymal-epithelial transition (EMT)-associated genes in a contact-dependent manner. Reciprocally, colon cancer cells were able to induce AMSCs to produce metastasis-related factors and cytokines, such as FGF10, VEGFC and matrix metalloproteinases (MMPs) in part through a mechanism of an activation of Wnt signaling, by which these factors in turn activate Wnt signaling of colon cancer cells. Intriguingly, an inhibition of Wnt signaling leads a reduced capacity of invasion and colony formation of colon cancer cells in vitro, and the tumorigenicity of cancer cells in a murine model. These findings thus suggest that the crosstalk between the Wnt signaling of cancer cells and paracrine factors of AMSCs has an implication in colon cancer malignancy. This study thus uncovers a novel Wnt-paracrine factors mediated-crosstalk between colon cancer cells and AMSCs in cancer malignancy.

Background: Lycium barbarum polysaccharide (LBP) has long been recognized as having a wide range of beneficial properties for improving proliferation. However, the protective effects and specific mechanisms of d ‐galactose‐induced testicular dysfunction in reproductively senescent rats are not fully understood. Materials and methods: A d ‐galactose‐induced senescence model in male rats and a d ‐galactose‐induced TM3 cell model were used to investigate the effects of LBP. The protective effect on testicular spermatogenic function was assessed by histological analysis and SA‐β‐gal staining. In addition, key calcium signaling pathway alterations involved in LBP were assessed using a multi‐omics approach and validated by tissue. Single‐cell sequencing data were used to further analyze the cellular heterogeneity of calcium signaling. Results: LBP significantly improved testicular structure, increased the number of spermatogonia in the seminiferous tubules, and significantly attenuated oxidative stress and testicular apoptosis. In addition, LBP restored the expression of key steroidogenic enzymes, as well as elevated levels of testosterone, follicle‐stimulating hormone (FSH), and estradiol (E2), and decreased levels of luteinizing hormone (LH). Mechanistically, LBP regulates key signaling pathways, including calcium homeostasis, Hippo and mTOR pathways, which play important roles in cell growth, apoptosis, and tissue regeneration. Single‐cell sequencing data show that calcium signaling is more active in the elderly compared to the young, mainly in Leydig cells, Round Spermatids, and Smooth Muscle Cells. In TM3 cell experiments, the LBP reduced SA‐β‐gal activity, downregulated aging markers (p16, p21, p53), and restored steroid production function. In addition, LBP regulated the Ca ² ⁺/CaM/CaMKII signaling pathway, improved calcium homeostasis, and reduced apoptosis in rats and cells. Conclusion: LBP improves d ‐galactose‐induced testicular spermatogenesis mainly by regulating calcium signaling and metabolic pathways and is closely related to elongating spermatids, round spermatids.