CALD1 facilitates epithelial-mesenchymal transition progression in gastric cancer cells by modulating the PI3K-Akt pathway

BACKGROUND CALD1 has been discovered to be abnormally expressed in a variety of malignant tumors,including gastric cancer(GC),and is associated with tumor progression and immune infiltration;however,the roles and mechanisms of CALD1 in epithe-lial-mesenchymal transition(EMT)in GC are unknown.AIM To investigate the role and mechanism of CALD1 in GC progression,invasion,and migration.METHODS In this study,the relationship between CALD1 and GC,as well as the possible network regulatory mechanisms of CALD1,was investigated by bioinformatics and validated by experiments.CALD1-siRNA was synthesized and used to trans-fect GC cells.Cell activity was measured using the CCK-8 method,cell migration and invasive ability were measured using wound healing assay and Transwell assay,and the expression levels of relevant genes and proteins in each group of cells were measured using qRT-PCR and Western blot.A GC cell xenograft model RESULTS Bioinformatics results showed that CALD1 was highly expressed in GC tissues,and CALD1 was significantly higher in EMT-type GC tissues than in tissues of other types of GC.The prognosis of patients with high expression of CALD1 was worse than that of patients with low expression,and a prognostic model was constructed and evaluated.The experimental results were consistent with the results of the bioinformatics analysis.The expression level of CALD1 in GC cell lines was all higher than that in gastric epithelial cell line GES-1,with the strongest expression found in AGS and MKN45 cells.Cell activity was significantly reduced after CALD1-siRNA trans-fection of AGS and MKN45 cells.The ability of AGS and MKN45 cells to migrate and invade was reduced after CALD1-siRNA transfection,and the related mRNA and protein expression was altered.According to bioinfor-matics findings in GC samples,the CALD1 gene was significantly associated with the expression of members of the PI3K-AKT-mTOR signaling pathway as well as the EMT signaling pathway,and was closely related to the PI3K-Akt signaling pathway.Experimental validation revealed that upregulation of CALD1 increased the expression of PI3K,p-AKT,and p-mTOR,members of the PI3K-Akt pathway,while decreasing the expression of PTEN;PI3K-Akt inhibitor treatment decreased the expression of PI3K,p-AKT,and p-mTOR in cells overexpressing CALD1(still higher than that in the normal group),but increased the expression of PTEN(still lower than that in the normal group).CCK-8 results revealed that the effect of CALD1 on tumor cell activity was decreased by the addition of the inhibitor.Scratch and Transwell experiments showed that the effect of CALD1 on tumor cell migration and invasion was weakened by the addition of the PI3K-Akt inhibitor.The mRNA and protein levels of EMT-related genes in AGS and MKN45 cells were greatly altered by the overexpression of CALD1,whereas the effect of overex-pression of CALD1 was significantly weakened by the addition of the PI3K-Akt inhibitor.Animal experiments showed that tumour growth was slow after inhibition of CALD1,and the expression of some PI3K-Akt and EMT pathway proteins was altered.CONCLUSION Increased expression of CALD1 is a key factor in the progression,invasion,and metastasis of GC,which may be associated with regulating the PI3K-Akt pathway to promote EMT.

Comparative analysis of two digestive tract reconstruction methods in total laparoscopic radical total gastrectomy

BACKGROUND The incidence of gastric cancer has significantly increased in recent years.Surgical resection is the main treatment,but the method of digestive tract reconstruction after gastric cancer surgery remains controversial.In the current study,we sought to explore a reasonable method of digestive tract reconstruction and improve the quality of life and nutritional status of patients after surgery.To this end,we statistically analyzed the clinical results of patients with gastric cancer who underwent jejunal interposition double-tract reconstruction(DTR)and esophageal jejunum Roux-en-Y reconstruction(RY).AIM To explore the application effect of DTR in total laparoscopic radical total gastrectomy(TLTG)and evaluate its safety and efficacy.METHODS We collected the relevant data of 77 patients who underwent TLTG at the Fourth Hospital of Hebei Medical University from October 2021 to January 2023.Among them,35 cases were treated with DTR,and the remaining 42 cases were treated with traditional RY.After 1:1 propensity score matching,the cases were grouped into 31 cases per group,with evenly distributed data.The clinical characteristics and short-and long-term clinical outcomes of the two groups were statistically analyzed.RESULTS The two groups showed no significant differences in basic data,intraoperative blood loss,number of lymph node dissections,first defecation time after operation,postoperative hospital stay,postoperative complications,and laboratory examination results on the 1st,3rd,and 5th days after operation.The operation time of the DTR group was longer than that of the RY group[(307.58±65.14)min vs(272.45±62.09)min,P=0.016],but the first intake of liquid food in the DTR group was shorter than that in the RY group[(4.45±1.18)d vs(6.0±5.18)d,P=0.028].The incidence of reflux heartburn(Visick grade)and postoperative gallbladder disease in the DTR group was lower than that in the RY group(P=0.033 and P=0.038).Although there was no significant difference in body weight,hemoglobin,prealbumin,and albumin between the two groups at 1,3 and 6 months after surgery,the diet of patients in the DTR group was better than that in the RY group(P=0.031).CONCLUSION The clinical effect of DTR in TLTG is better than that of RY,indicating that it is a more valuable digestive tract reconstruction method in laparoscopic gastric cancer surgery.