The Molecular Mechanism Of Colorectal Cancer In Spontaneous Diabetic Gerbils And Screening Of LncRNA Associated With Diabetes Mellitus And Vascular Diseases In Peripheral Blood

ObjectiveDiabetes mellitus(DM)is a heterogeneous disease in terms of its etiology,clinical behavior,and molecular mechanism as well as in terms of its association with colorectal cancer(CRC).The relationship between CRC and DM is highly complex such that it is important to investigate CRC-related gene expression profiles and tumor formation in diabetic animal models.Of note,our laboratory was the first to generate a spontaneous diabetic gerbil line.Therefore,we established a colitis-associated CRC model in diabetic gerbils and explored the gene expression profiles and pathways involved in the development of CRC in the DM background.Moreover,recent svudies have shown that long non-coding RNA(lncRNA)is involved in cell differentiation,cell cycle processes,individual development and many other important life processes and are closely related to major human diseases,including diabetes and its complications.But less is known about the IncRNA profile alteration of leucocytes in diabetes.The another purpose of this study was to explore lncRNA expression changes of leucocytes in response to diabetesMethods1.A CRC model was developed by azoxymethane/dextran sulfate sodium(AOM/DSS)induction in diabetic gerbils and was confirmed by symptom assessment and morphological and histopathological analyses.Biochemical indexes and inflammatory factors were tested using a Synchron CX5 system and multiplex panel,respectively.Colorectal tumors and adjacent tissues were compared for differentially expressed genes(DEGs)using Affymetrix Rat Gene 2.0 ST GeneChip(?)arrays.2.RNA sequence was performed using white blood cells from patients diagnosed with T1DM,T2DM,T2DM with macrovascular complication and healthy controls.Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway and Gene Ontology(GO)analyses were utilized to annotate the DEGs.Coding non-coding co-expression(CNC)analysis was performed to construct a co-expression network.Results1.An AOM/DSS-induced CRC model with a tumor frequency of 50%was established in diabetic gerbils.Pathological changes of the colorectal tumors of diabetic gerbils included severe lymphocyte infiltration and adenocarcinoma.Although most biochemical indexes and inflammatory factors showed no significant differences between the tumor,non-tumor and control groups,there were significant differences in two biochemical indexes(CR-S,AMY7)and two inflammatory factors(IL-2,MIP-la)between the three groups.We identified 798 up-regulated and 840 down-regulated protein-coding genes that were shared among tumor tissues but not with adjacent tissues.These deregulated genes were found to play various roles in diverse processes,including regulation of MAPK signaling.KEGG analysis identified 265 pathways;17 pathways were enriched,and 5 of these enriched pathways were found to be associated with both CRC and DM.However,the expression profiles of several important genes in proteoglycan(PG)pathways,such as AKT,were inconsistent with those from previous reports.2.We found 22 lncRNAs and 43 mRNAs were differentially expressed between the T2DM group and the T1DM group,of which,9 DEGs only expressed in T2DM patients.Pathway and GO analyses demonstrated that dysregulated IncRNAs were mainly associated JAK-STAT cascade.Furthermore,CNC analysis identified 40 pairs of co-expressed IncRNA-mRNAs in our patient cohort,whereas the expression of only 4 target mRNAs showed statistically significance.3.We found 16 lncRNAs and 54 mRNAs were differentially expressed in the diabetic macrovasculopathy group compared to the T2DM group,of which,9 DEGs were novel lncRNAs.Pathway and GO analyses indicated that dysregulated mRNAs were closely relative with inflammation and immunity,such as cytokine production,cytokine-mediated signaling pathway,immune response and type ? interferon.Furthermore,CNC analysis identified 2 pairs of co-expressed lncRNA-mRNAs in our patient cohort(R>0.9).The target mRNAs of lncRNA,MSTRG.110xxx,were STX3 and ALPK1.Conclusion1.We established a novel DM-associated CRC model in gerbils,and the gene expression data provide new insights into the molecular mechanisms of colorectal tumorigenesis.Moreover,certain identified genes may play important roles in the development of CRC under diabetic conditions.2.We found a set of IncRNAs were differentially expressed in white blood cells in response to T1DM compared to T2DM.The results suggested that these differently expressed IncRNAs may become novel biomarkers for the clinical diagnosis and classification of the DM.Moreover,JAK-STAT signaling pathway may play an important role in the the pathogenesis of T2DM.3.This study identified aberrantly expressed IncRNAs and mRNAs in patients with diabetic macrovasculopathy.The IncRNA MSTRG.110xxx level was significantly decreased in patients with diabetic macrovasculopathy.Dysregulation of IncRNA MSTRG.110xxx may resulted in increased expression of its target genes,STX3 and ALPK1.These results indicate that lncRNA MSTRG.110xxx might perform as a new regulator,enhancing Inflammatory response and promoting the occurrence and development of related vascular complications of T2DM.