The Expression And Clinical Significance Of NPDC1 In Colorectal Cancer With Nerve Infiltration

Research Background and Purpose:Colorectal cancer(CRC)is one of the most prevalent and lethal malignant tumors,which caused more than seven hundred thousand deaths per year.Moreover,it is estimated that the number of deaths will increase to 1.1 million and the newly diagnosed CRC patients will more than 2.2 million every year by 2030,which places a significant health and economic burden on society.Therefore,it is urgent to effectively prevent and treat colorectal cancer.Traditional perspectives have assumed that solid tumors mainly spread through three classical ways: direct invasion,lymphatic metastasis,and blood metastasis.In recent years,nerve infiltration has been considered the fourth way of tumor metastasis,which is involved in tumor later metastasis or local recurrence.As precision medicine progresses,new diagnostics,biomarkers,and therapeutic strategies are needed.In this study,Neural Proliferation Differentiation and Control 1(NPDC1)is located on human chromosome 15,encoding a 325-amino acid polypeptide.Previous studies have reported that NPDC is mainly involved in the evolution and development of nervous system diseases.However,its regulatory role in tumors has not been reported.Herein,we aim to explore the expression level and clinical significance of NPDC1 in colorectal cancer.Methods:1.Scheme of the genetic screenFirstly,the ENSEMBL database was used to get the set of genes related to nerves and synapses.Then,the TCGA database was further analyzed for joint analysis to screen out the genes related to colon cancer nerve infiltration and prognosis.Finally,we located the target gene NPDC1 through the random forest method.The expression of NPDC1 was further verified by Log2(TPM+0.01)paired T-test,Oncomine database,TIMER database,and HPA database.2.Functional analysis of NPDC1 geneThe TCGA-COAD data were analyzed by Xena and spearman correlation analysis.To search for signaling pathways associated with NPDC1,the positive and negative related genes were enriched by GSEA,GSVA,GO,and KEGG analysis.3.Validation of the expression level NPDC1The 63 pathology slices were collected from patients undergoing colorectal surgery in the Second Hospital of Jilin University from May 2016 to December 2017,and 10 fresh colorectal cancer tissue was collected from October 2022 to December2022.We detected the expression level of NPDC1 in tumor tissues,paracancerous tissues,and normal tissues by Rt-q PCR,WB,and IHC.Furthermore,the relationship between NPDC1 expression and clinicopathologic features was analyzed.Results:1.NPDC1 is highly expressed in colorectal cancerThrough combining the ENSEMBL database and TCGA-COAD sample set together,we first screened 13 genes by Kaplan-Meier and Cox regression analyses:UNC5D,CHD5,SALL1,MANF,ADRA2 B,DLX2,NTF4,PTPRD,NPDC1,LRRN4,NPAS1,SYN1,SYT8.Random forest method was then applied to narrow the list further.After being intersected with genes of 0.25 true importance,the NPDC1 gene was obtained from the 13 genes above,which may be closely related to nerve infiltration and survival prognosis of colon cancer.The high expression of NPDC1 in colorectal cancer was further verified by Oncomine database,TIMER2.0 database,and HPA database.2.Functional analysis of NPDC1 geneGene correlation analysis found that NPDC1 was positively correlated with a variety of cell cycle regulation,ion channel proteins,and signaling pathway receptors,while negatively correlated with a variety of apoptosis and autophagy-related proteins,especially with HMG20 B,which is considered to be necessary for the correct entry into the G2 phase and mitosis.It is suggested that NPDC1 may regulate the occurrence and development of colon cancer by regulating the cell cycle.GO,KEGG,GSEA,and GSVA analysis showed that NPDC1 was mainly related to some pathways related to organocyte regulation and nutrient metabolism,such as enrichment in mitochondrial regulation,cell delivery and assembly regulation,Notch signaling pathway,phospholipase D signaling pathway,glycolysis,P53 pathway,and other signaling pathways.3.Expression verification of NPDC1 in clinical tissuesRT-q PCR showed that the expression level of NPDC1 m RNA in colorectal cancer tissues was higher than that in normal tissues,and WB and IHC further verified that the expression level of NPDC1 protein in colorectal cancer tissues was higher than that in normal tissues and paracancerous tissues.The expression level of NPDC1 was correlated with nerve infiltration(P < 0.05),but not with sex,age,vascular invasion,TNM stage,and CEA level(P > 0.05).Kaplan-Meier survival analysis showed no difference between high and low expression groups(P=0.376).Conclusion:NPDC1 expression is upregulated in colorectal cancer tissues compared with normal and paracancerous tissues.Moreover,gene function analysis found that NPDC1 is associated with several signaling pathways regulating the progression of colorectal cancer,and the expression level of NPDC1 is correlated with nerve infiltration.These results suggest that NPDC1 may be involved in the regulation of nerve infiltration in colorectal cancer.Taken together,NPDC1 may be a key gene in the occurrence and development of colorectal cancer.