CDX2 and Reg IV Expression and Correlation in Gastric Cancer

Abstract

Background: Ectopic expression of CDX2 is associated with the development and progression of gastric cancer. Previous studies showed that CDX2 may be an upstream regulator of Reg IV expression in gastric cancer, and our previous report showed that Reg IV upregulated SOX9 expression and enhanced cell migration and invasion in gastric cancer cells. However, the regulatory roles of CDX2 have not been clarified in gastric cancer, and the correlation between CDX2 and Reg IV requires further study.Methods: CDX2 and Reg IV were examined in gastric cancer specimens and paired adjacent tissues via real-time PCR and immunohistochemistry (IHC). The association between CDX2 and Reg IV was assessed using the χ2-test and Spearman’s rank correlation. To verify their relationship, knockdown and exogenous expression of CDX2 or Reg IV were performed in AGS and MKN-45 gastric cancer cells, and their expression was subsequently analyzed via a real-time PCR and western blotting. Wound-healing and Transwell assays were used to examine migration and invasion in AGS and MKN-45 cells following CDX2 silencing or overexpression.Results: A positive correlation was observed between CDX2 and Reg IV expression at the mRNA and protein levels in gastric cancer tissues. CDX2 silencing significantly downregulated Reg IV expression, and CDX2 overexpression significantly upregulated Reg IV expression in AGS and MKN-45 cells. Neither Reg IV silencing nor overexpression had any effect on CDX2 protein expression in AGS or MKN-45 cells, even though both affected the expression of CDX2 mRNA. Functionally, CDX2 silencing significantly inhibited cell migration and invasion, and CDX2 overexpression significantly promoted cell migration and invasion in AGS and MKN-45 cells.Conclusions: Our findings demonstrate that CDX2 expression was positively correlated with that of Reg IV in gastric cancer, and CDX2 promoted cell migration and invasion through upregulation of Reg IV expression in gastric cancer cells.

Circ_0017274 acts on miR‐637/CDX2 axis to facilitate cisplatin resistance in gastric cancer

“…In addition to its important role in intestinal development, CDX2 has also been shown to play a role in several types of cancer. In GC, CDX2 downregulation markedly repressed GC cell metastasis, while CDX2 overexpression did the opposite 21 . Whether CDX2 can regulate the progression of CDDP‐resistant GC cells remains unknown.…”

“…In GC, CDX2 downregulation markedly repressed GC cell metastasis, while CDX2 overexpression did the opposite. 21 Whether CDX2 can regulate the progression of CDDPresistant GC cells remains unknown. Our study comprehensively validated the expression characteristics and mechanism of action of CDX2 in CDDP-resistant GC cells.…”