1.Transcriptomic Characteristics Of Distance-related Field Cancerization In Rectal Cancer Patients 2.Similarities Of The Peripheral Blood Leukocytes Expression Profiles Between Pregnant Women And Tumor Hosts

PART ?Transcriptomic characteristics of distance-related field cancerization in rectal cancer patientsField cancerization(FC)occurs in various epithelial carcinomas,including colorectal cancer,which indicates that the molecular events in carcinogenesis might occur in normal tissues extending from tumors.However,the transcriptomic characteristics of FC in colorectal cancer(CRC)remain largely unexplored.To investigate the changes in gene expression associated with proximity to the tumor,we analyzed the global gene expression profiles of cancer tissues and histologically normal tissues taken at various distances from the tumor(1 cm,5 cm and the proximal end of the resected sample)from 32 rectal cancer patients.Significantly differentially expressed genes related to the distance from the tumor were screened by linear mixed effects analysis using the lme4 package in R.The distance-related differentially expressed genes that were gradually up-regulated(n=302)or gradually down-regulated(n=568)from normal tissues to the tumor were used to construct protein-protein interaction(PPI)networks.Three subnetworks among the gradually up-regulated genes and four subnetworks among the gradually down-regulated genes were identified using the MCODE plugin in the Cytoscape software program.The most significantly enriched Gene Ontology(GO)biological process terms were "ribosome biogenesis","mRNA splicing via spliceosome",and "positive regulation of leukocyte migration" for the gradually up-regulated subnetworks and "cellular calcium ion homeostasis","cell separation after cytokinesis","cell junction assembly",and "fatty acid metabolic process"for the gradually down-regulated subnetworks.Combined with the previously constructed multistep carcinogenesis model for analysis,50.59%of the genes in the subnetworks(43/85)displayed identical changes in expression from normal colon tissues to adenoma and colon cancer.We focused on the 7 genes associated with fatty acid metabolic processes in the distance-related down-regulated subnetwork.Survival analysis of patients in the CRC dataset from The Cancer Genome Atlas(TCGA)revealed that higher expression of these 7 genes,especially CPT2,ACAA2 and ACADM,was associated with better prognosis(p = 0.034,p = 0.00058,p = 0.039,p = 0.04).Cox proportional hazards regression analysis revealed that CPT2 was an independent prognostic factor(p = 0.004131).Our results demonstrate that field cancerization occurs in CRC and affects gene expression in normal tissues extending from the tumor,which may provide new insights into CRC oncogenesis and patient progression.PART ?Similarities of the peripheral blood leukocytes expression profiles between pregnant women and tumor hostsTumor cells mimic the normal course of pregnancy to proliferate,invade,and induce immunotolerance.Trophoblast cells and cancer cells are very similar in biological behavior,both to establish a local microenvironment suitable for growth and to edit the maternal/hosts' immune system by similar mechanisms.At present,the study on the changes of immune status of pregnancy and tumor is mainly focused on the local microenvironment and the involved immune cells.The omics study on the change of the overall immune status is still less.We analyzed 734 white blood cell counts during pregnancy of 237 pregnant women and found that white blood cell counts from 16 to 24 weeks gestation were significantly higher than at other times,which were higher than the normal upper limit.Using the method of expression microarray,we analyzed the global expression profiles of peripheral blood leukocytes sampling from 17 pregnant women at different gestation weeks and 12 healthy women of childbearing age.We found that among the first 25 genes significantly increased during pregnancy,13 genes(52.00%)were related to neutrophils,while NK cell-related molecules were significantly down regulated during pregnancy.WGCNA was used to analyze the correlation between differential expressed genes and gestational weeks.Two modules have positive and negative correlation with gestational week were identified and contain 140 and 137 genes,respectively.GO function annotations showed that the gestational week-related up-regulated genes were associated with "defense response to bacterium","defense response to fungus" and "interaction with symbiotic",whereas the gestational week-related down-regulated genes were associated with the "natural killer cell chemotaxis","Cytolysis" and "regulation of leukocyte activation." KEGG pathway enrichment analysis showed that the gestational week-related up-regulated genes were associated with "phagosome","lysosome" and so on.while the gestational week-related down-regulated genes were associated with "Natural killer cell mediated cytotoxicity".GSEA analysis showed defense response to bacterium,defense response to fungus,type ?interferon signaling pathway,lymphocyte migration and blood coagulation functions positively correlated with pregnancy,whereas translational termination,translational elongation,selenocysteine metabolism,viral transcription,mitochondrial translation initiation,elongation,and termination and the mitochondrial respiratory chain complex ?assembly negatively correlated with pregnancy.Combined the peripheral blood leukocyte RNA sequencing results of lung cancer patients and healthy control of our laboratory for analysis,we found that some neutrophil-related genes up regulated in lung cancer patients,which was consistent with changes in pregnancy;but granzyme B and perforin down regulated in peripheral blood leukocytes in patients with lung cancer,which was contrary to pregnancy.GSEA analysis showed defense response to bacterium,defense response to fungus and type ? interferon signaling pathway were positively correlated with lung cancer,which was consistent with pregnancy;whereas NK cell cytotoxicity was positively correlated with lung cancer and negatively correlated with pregnancy.In conclusion,our study depicts the transcriptiomic characteristics of peripheral blood leukocyte in pregnancy and compared with that of lung cancer hosts,which could reflect the global immune changes.We found that neutrophil-associated molecules and functions were significantly upregulated in pregnancy and tumors,whereas NK cell activity and enzymes down regulated in the pregnancy and up regulated in tumor hosts.The similarities and differences of the immunotolerance mechanisms between the physiologic state of pregnancy and the pathologic state of tumor host immune tolerance will be helpful in in-depth understanding of the tumor immune tolerance mechanism and in identifying new potential targets for tumor immune therapy.