A reliable mouse model of liver and lung metastasis by injecting esophageal cancer stem cells (CSCs) through tail-vein injection

BACKGROUND

Esophageal Squamous Cell Carcinoma (ESCC) is a highly aggressive tumor with increased metastatic potential. Recent evidence suggests that esophageal CSCs have a crucial role in tumor initiation, progression, and resistance to conventional anti-cancer therapies. The study aimed to develop mouse model to mimic the late steps of the metastasis process using a tail-vein injection of esophageal CSCs.

METHODS AND RESULTS

The sphere formation assay was used to enrich CSCs. For analysis of tumorigenicity, YM-1 adherent cells and enriched CSCs were injected subcutaneously into dorsal flank of nude mice. The expression of SLUG, E-cad, and CTHRC1 genes was examined by Real-Time qRT-PCR and immunohistochemistry (IHC) methods. To assess the metastatic potential of adherent YM-1 cells and their enriched CSCs, we injected the cells into the tail vein of nude mice. Our findings showed the up-regulation of SLUG and down-regulation of E-cad in the esophageal CSC-derived tumors (ECSCTs) compared to adherent cells-derived tumors. There was no statistically significant difference between CTHRC1 gene expressions in both groups of tumors. IHC staining confirmed the higher expression of SLUG protein in ECSCTs compared to adherent cell-derived tumors. Enriched CSCs were able to metastasize to the lungs and livers after three months, but, metastasis of adherent cells wasn't observed.

CONCLUSION

Our study showed esophageal CSCs injected through the tail-vein injection can migrate and metastasize to the lung and liver after three months. The developed metastatic mouse model can be a valuable and relevant model to investigate the molecular and cellular mechanisms of metastasis and develop successful targeted therapies against ESCC. The present study is one of the few studies that investigate the metastasis of esophageal cancer stem cells (ESCC type) through injection into the tail vein of nude mice.

The neuropeptide substance P/neurokinin-1 receptor system and diabetes: From mechanism to therapy

Diabetes is a significant public health issue known as the world's fastest-growing disease condition. It is characterized by persistent hyperglycemia and subsequent chronic complications leading to organ dysfunction and, ultimately, the failure of target organs. Substance P (SP) is an undecapeptide that belongs to the family of tachykinin (TK) peptides. The SP-mediated activation of the neurokinin 1 receptor (NK1R) regulates many pathophysiological processes in the body. There is also a relation between the SP/NK1R system and diabetic processes. Importantly, deregulated expression of SP has been reported in diabetes and diabetes-associated chronic complications. SP can induce both diabetogenic and antidiabetogenic effects and thus affect the pathology of diabetes destructively or protectively. Here, we review the current knowledge of the functional relevance of the SP/NK1R system in diabetes pathogenesis and its exploitation for diabetes therapy. A comprehensive understanding of the role of the SP/NK1R system in diabetes is expected to shed further light on developing new therapeutic possibilities for diabetes and its associated chronic conditions.