c-Myc Knockout as a Model for Gene Editing for Training Healthcare Professional Students

Correction of genetic errors, commonly known as gene editing, holds promise to treat diseases with unmet medical needs. However, gene therapy trials do encounter unwanted outcomes, because of an incomplete understanding of the disease states, and gene therapy processes, among others. This situation encourages a concept that healthcare professionals receiving laboratory research training will not only identify inadequacies in basic biomedical knowledge of gene therapies but also provide tangible refinements. To this end, we have undertaken the PharmD student training in gene editing in a basic research laboratory setting. As a model, MYC gene was chosen for knockout using CRISPR-Cas9 method in HT29 and OVCAR8 cells. Students were involved in the design of MYC-specific gRNAs, subcloning into Cas9-carrying plasmid, and selection of knockout clones from the transfected cells. Subsequently, genomic DNA isolation and sequencing, analysis of clonal DNA sequences using online bioinformatics tools, western blotting, cell proliferation and cell division cycle experiments, were performed to characterize the MYC knockout clones. Results presented in this communication suggest that healthcare professionals who received laboratory training gain a better understanding of the disease states and mechanisms, gene therapy protocols, limitations of gene therapies, ability to critically evaluate the literature and confidence in the oversight of gene therapies in the clinic.

INDUCTION OF C-MYC GENE AMPLIFICATION BY HYDROXYUREA AND ITS INHIBITION BY HOMOHARRINGTONINE

Induction of c-myc gene amplification in L1210 cells by hydroxyurea and its inhibition by homohar-ringtonine were investigated using the DNA-DNA molecular hybridization technique. When the cells were treated with hydroxyurea 1.0 mM for 16 hours, and incubated a further 16 hours in a drug-free medium, the c-myc gene amplified 23.5-fold. If homohar-ringtonine 50 μM was used at the same time as hydroxyurea, gene amplification did not occur. Cycloheximide, an inhibitor of protein biosynthesis, produced a similar effect. Our results indicated that a (or some) protein factor(s) might be involved in gene amplification. Detailed analysis showed that the synthesis of this protein factor(s) started 4 hours before the initiation of the S phase but did not continue in the S phase. It was also found that this protein factor(s) was very labile and began to degrade 2 hours after its appearance.

THE EXPRESSIONS OF HBV X GENE AND ets-2, IGF-Ⅰ, c-myc AND N-ras ONCOGENES IN HUMAN HEPATOCELLULAR CARCINOMA AND TUMOR-ADJACENT TISSUES

The expressions of HBV X gene and ets-2, IGF-I, c-myc and N-ras were studied in 7 pairs of human primary hepatocellular carcinoma (PHC) and tumor-adjacent tissues, using RNA hybridization and im-munoblot methods. The results showed that specific 17 and 28 kD HBV X gene products (HBxAg) were existed in a portion of PHC and tumor-adjacent tissues. The 17 kD HBxAg was detected in the sera of 3 patients who also had 17 kD HBxAg in their liver tissues. Multiple expressions of oncogenes such as ets-2, c-myc and N-ras were observed in PHC and tumor-adjacent tissues that had HBxAg expressed, indicating HBxAg might function as a transactivator in the course of intracellular proto-oncogene activation. It is also observed that in some tumor-adjacnet tissues the expressions of ets-2, c-myc and N-ras were higher than those in corresponding PHC. The relationship of HBxAg to the expression of est-2, IGF-Ⅱ, c-myc and their possible roles in the carcinogenesis of PHC are discussed.

Deregulated c-myc expression in quiescent CHO cellsinduces target gene transcription and subsequent apoptotic phenotype

Human c-myc cDNA was fused with the hormonebinding domain (HBD) cDNA of murine estrogen receptorgene and the chimeric gene was introduced into the CHOcells. The fusion protein, c-MycER, becomes activatedwhen the synthetic steroid, 4-hydroxy-tamoxifen (OHT),binds HBD. Activated c-MycER, likely c-Myc, can inducequiescent CHO cells reentry into S phase and subsequentcell death under serum-free condition. In addition, theexpression of some proposed c-myc target genes such asODC, MrDb, cad, rcc1 and rc1 were found to increase uponOHT induction before S, phase entry and apoptosis, indicating that these target genes are involved in cell cycleregulation and/or apoptosis control. However, the mutantD106-143c-MycER protein does not have above activities.

Gene therapy with antisense c-myc adenovirus for human gastric carcino-ma cell line in vitro and for implanted carcinoma in nude mice

Objective:To study the effects of recombinant antisense c-myc adenovirus (rAS-c-myc-Ad) on SGG 7901 human gastric carcinoma cell line in for and in nude mice. Methods:The effects of rAS-c-myc-Ad and LacZ-Ad on SGG 7901 gastric carcinoma cells were observed with X-galstaining, MTT, DNA gradient degradation test, TUNEL, flow cytometry, PCR and western blot. The therapeutic effects of rAS-c-myc-Ad on the implanted ax 7901 cells in nude mice were also ob served.Results: rAS-c-myc-Ad significantly inhibited the growth of SGG 7901 cells and induced their apoptosis. After the treatment of rAS-c-myc-Ad, the prolifetion rate of the cells was decreased by 44’ l% in de and SGC 7901 cells failed to form caxcinoma ther they were implanted into nude mice. Injection of rAS-c-myc-Ad into the carcinoma subcutaneously implanted to the nude mice significantly inhibited the growth of the implanted carcinoma with an inhibition rate of 68. 9%. Conclusion: rAS-c- myc- Ad significantly inhibits the growth of SGG 7901 human gastric carcinoma cells in vitro and in nude

INCREASED EXPRESSION OF PDGF AND C-MYC GENES IN LUNGS AND PULMONARY ARTERIES OF PULMONARY HYPERTENSIVE RATS INDUCED BY HYPOXIA

The role of growth factors and proto-oncogene in pulmonary vascular structural remodelling is not well known.The present study examined gene expression of platelet-derived growth factor(PDGF)-A and -B chain and proto-oncogene,c-myc,in lung tissue and pulmonary artery of rats exposed to hypoxia and compared to those levels of gene expression in normal rats.Normal lungs and pulmonary artery expressed PDGF-A chain transcript of 1.7 kb and PDGF-B chain transcript of 3.5 Kb.The c-myc transcript of 2.2 kb was expressed as well. After hypoxic exposure for 7 and 14 days mRNA levels of PDGF-B chain and cmyc were elevated significantly compared with those of control rats.PDGF-A chain mRNA increased after hypoxia for 7 days,and then declined.These results suggest that activation of autocrine and/or paracrine is important in proliferation mechanism of pulmonary artery smooth muscle cells in hypoxic pulmonary hypertensive rats.

Expressions of oncogenes c-fos and c-myc in skin lesion of cutaneous squamous cell carcinoma

Objective:To explore the expressions of c-fos and c-myc in skin lesion of cutaneous squamous cell carcinoma(CSCC).Methods:Using retrospective analysis.73 cases of CSCC were selected from Department of Dermatology,the Second Affiliated Hospital of Xi'an Jiaotong University.which were removed between January 2000 and January 2012.It was considered as experimental group.Meanwhile.11 cases of normal skin specimens of non tumor patients were selected as control group.The expression level of c-fos and c-myc was compared in the two groups.Results:The expressions of c-fos[72.60%(53/73)]and c-myc[83.56%(61/73)]in experimental group were statistically significant(P≤0.05)compared with control group(0%).Expression of c-myc protein was negatively related to differentiation of CSCC.The difference was statistically significant(X^2=7.26.P=0.001<0.05).While expression of c-fos protein was positively related to differentiation of CSCC.which was statistically significant(X^2=7.47,P=0.0012<0.025).Conclusions:The expression level of c-fos and c-myc can be used as an importan indicator of CSCC differentiation,and it has closely connection with the differentiated degree,which can guide clinical prognosis.

A STUDY OF C-MYC ONCOGENE EXPRESSION AND AMPLIFICATION IN COLORECTAL CANCER

Expression of c-myc oncogene transcripts in colorectal neoplasia was studied in paraffin embedded tissue sections from 25 patients undergoing surgery and from the rectal carcinoma cell line HR-8348 by using in situ hybridization,and its amplification was investigated in tumor and normal mucosa tissue from 25 coloproctomy samples by slot blot hybridization. Overexpression of this gene was seen in 78% (7/9) of the benign adenomas and 91% (20/22) of the malignancies sampled. There was no significant correlation between overexpression and the histologic type or grade, and no significant relationship between the level of expression and clinical stage was found, although overexpression was apparently more common in tumors with metastasis. Amplification of the gene was found in 0 of 4 benign adenomas and 7 of 22 malignancies. No obvious correlation was found between amplification and histological type or grade, though amplification was more frequent in tumors with metastasis. Amplification was also found in 2 adenomas with malignant change. The results suggest that multiple factors are involved in the progression of colorectal cancer , and in situ hybridization with a nonradiolabeled probe is useful in the detection of gene expression.

Progress in clinical diagnosis and treatment of colorectal cancer with rare genetic variants

Targeted therapy is crucial for advanced colorectal cancer(CRC) positive for genetic drivers. With advances in deep sequencing technology and new targeted drugs, existing standard molecular pathological detection systems and therapeutic strategies can no longer meet the requirements for careful management of patients with advanced CRC. Thus, rare genetic variations require diagnosis and targeted therapy in clinical practice. Rare gene mutations, amplifications, and rearrangements are usually associated with poor prognosis and poor response to conventional therapy. This review summarizes the clinical diagnosis and treatment of rare genetic variations, in genes including erb-b2 receptor tyrosine kinase 2(ERBB2), B-Raf proto-oncogene, serine/threonine kinase(BRAF), ALK receptor tyrosine kinase/ROS proto-oncogene 1, receptor tyrosine kinase(ALK/ROS1), neurotrophic receptor tyrosine kinases(NTRKs), ret proto-oncogene(RET), fibroblast growth factor receptor 2(FGFR2), and epidermal growth factor receptor(EGFR), to enhance understanding and identify more accurate personalized treatments for patients with rare genetic variations.

Promoter hypermethylation of tissue specific tumor supressor genes and point mutation in K-ras, c-myc proto-oncogenes in urinary (transitional cell) bladder carcinoma

In a total of 83 UN specimens were investigated for proto-oncogene mutations, tumor supressor genes promoter methylation status and c-myc and Ki-67 expression. Point mutations in c-myc were detected in cases with high grade and proliferation index. Mutated K-ras proto-onco- gene profiles were detected in 17 (21%) tumoral spiecemens that examined. Tumor specimens were also showed hypermethylated promoter domain for the SFRP2, MGMT tumor supressor genes. These findings showed the combine effect of mutated c-myc and K-ras oncogene and epigenetic inactivation of tissue specific tumor supressor genes (TS) play a crucial role in tumor progression and recurrence in UN carcinogenesis.

Proliferation and C-myc Gene Expression of Smooth Muscle Cells in Rabbit Carotid Artery after Stenting

Objectives To investigate theproliferation of smooth muscle cells (VSMCs) and theexpression of c-myc gene in rabbit carotid arieries af-ter stenting. Methods Platinium-Iridium stent wereimplanted into the right carotid arteries of 16 rabbitsunder vision. 7,14,30 and 90 days after the stentingprocedure, morphological changes of VSMCs were ob-served under light and transmission electron micro-scope. The c-myc gene expression was detected by insitu hybridization (ISH) and immunohistochemicalstaining. Results 7 days afer stenting, the pheno-type of VSMCs changed from contractile to syntheticphenotype; there were a number of proliferative VSM-Cs in the neointima. At 14 and 30 days, there weresynthetic and transitive VSMCs. At 90 days, the phe-notype of VSMCs recovered to contractile phenotype.The ultrastructure of typical synthetic phenotype ofVSMCs were round, containing a large amount ofrough endoplasmic reticulum and mitochondria. C-myc expression were positive both by ISH and im-munohistochemical staining. Conclusions C - mycgene expression increases and closely relates to VSM-Cs proliferation afer stenting. It may play an impor-tant role in the in-stent restenosis.

β-catenin up-regulates the expression of cyclinD1, c-myc and MMP-7 in human pancreatic cancer: Relationships with carcinogenesis and metastasis

AIM:To investigate whether abnormal expression of β-catenin in conjunction with overexpression of cyclinD1, c-myc and matrix metalloproteinase-7 (MMP-7) correlated with the carcinogenesis, metastasis and prognosis of pancreatic cancer, and to analyze the relationship of β-catenin expression with cyclinDl, c-myc and MMP-7 expression. METHODS: Using immunohistochemistry,we examined the expression of β-catenin, cyclinD1,c-myc and MMP-7 in 47 pancreatic adenocarcinoma tissues, 12 pancreatic intraepithelial neoplasia (PanIN) and 10 normal pancreases, respectively. Proliferation cell nuclear antigen was also tested as the index of proliferative activity of pancreatic cancer cells. RESULTS: In 10 cases of normal pancreatic tissues, epithelial cells showed equally strong membranous expression of β-catenin protein at the cell-cell boundaries, but the expression of cyclinDl, c-myc and MMP-7 was negative. The expression of β-catenin, cyclinD1, c-myc and MMP-7 in PanIN and pancreatic adenocarcinoma tissues had no significant difference [6/12 and 32/47 (68.1%), 6/12 and 35/47 (74.5%), 5/12 and 33/47 (70.2%), 7/12 and 30/47 (63.8%), respectively]. The abnormal expression of β-catenin was significantly correlated to metastasis and one-year survival rate of pancreatic cancer, but had no relation with size, differentiation and cell proliferation. The expression of cyclinD1 was correlated with cell proliferation and extent of differentiation, but not with size, metastasis and one-year survival rate of the pancreatic cancer. The expression of c-myc was not correlated with size, extent of differentiation, metastasis and 1-year survival rate, but closely with cell proliferation of pancreatic cancer. The overexpression of MMP-7 was significantly associated with metastasis and 1-year survival rate of pancreatic cancer,but not with size, extent of differentiation and cell proliferation.There was a highly significant positive association between abnormal expression of β-catenin and overexpression of cyclinD1, c-myc and MMP-7 not only in PanIN (r= 1.000, 0.845, 0.845), but also in pancreatic cancer (r= 0.437, 0.452, 0.435). CONCLUSION: The abnormal expression of β-catenin plays a key role in the carcinogenesis and progression of human pancreatic carcinoma by up-regulating the expression of cyclinDl, c-myc and MMP-7, resulting in the degradation of extracellular matrix and uncontrolled cell proliferation and differentiation,β-catenin abnormal expression and MMP-7 overexpression may be considered as two useful markers for determining metastasis and prognosis of human pancreatic cancer.

Expression of p53 and C-myc genes and its clinical relevance in the hepatocellular carcinomatous and pericarcinomatous tissues

AIM: To investigate the possible roles of p53 and C-mycgenes in the primary hepatocellular carcinogenesis and therelationship between the liver hyperplastic nodule(LHN) andhepatocellular carcinoma(HCC).METHODS: The expression of p53 and C-myc genes wasdetected immunohist-ochemically in 73 and 60 cases of HCCand pericarcinomatous tissues, respectively .RESULTS: The positive expression of p53 in HCC wassignificantly higher than that in pericarcinomatous tissues(P＜0.05). In pericarcinomatous tissues, the p53 expressionwas observed only in LHN, but not in liver cirrhosis (LC) andnormal liver tissues. The positive expression rate of C-mycin HCC or LHN was significantly higher than that in LC ornormal liver tissues (P＜0.05 and P＜0.01), however, nosignificant difference was found between HCC and LHN(P＞0.05). The positive expression rate of p53 and C-myc inHCC was correlated with the histological differentiation, thatin the poorly differentiated was significantly higher than thatin well differentiated samples (P＜0.05).CONCLUSION: The overexpression of p53 and C-myc genesmight play a role in the carcinogenesis of HCC; And LHNseems a preneoplastic lesion related to hepatocarcinogenesis;No evidence supports that LC contribute directly to thehepatocarcinogenesis.

Distribution of oval cells and c-myc mRNA expression in mouse hepatocarcinogenesis

BACKGROUND: This study was designed to assess theroles of oval cells and c-myc mRNA in the process of hepa-tocarcinogenesis and to clarify the function of carcinogenec-myc in the development of hepatocellular carcinoma( HCC) and the mechanism of inhibitory function of uscha-ridin on HCC in mouse hepatocarcinogenesis.METHODS: A total of 120 clean SD mice were divided intonormal group, cancer induction group, and interventiongroup. The normal group was fed with standard foragewhile the rest two groups were given p-dimethylaminoazo-benzene (DAB) to induce cancer. Thirteen weeks after in-duction of cancer, the two groups were fed with standardforage and water. Once the pattern was set up, the inter-vention group was given uscharidin injection into the ab-dominal cavity from the first week to the 14th week. Onthe 2nd, 4th, 6th, 8th, 10th, 12th, 14th, 16th, 18th, 20th,22nd, and 24th week, all mice were killed and biopsiedfrom the liver lobe for pathological analysis. At the sametime, the number of tumor nodes was counted and the ex-pression of c-myc mRNA was tested by RT-PCR.RESULTS: Since the 2nd week after cancer induction, pro-liferated oval cells could be seen in the portal area. Initially,the oval cells appeared in the cortical layer of the portalarea, then proliferated gradually and immigrated into theliver parenchyma. In the period of fibrosis after liver proli-feration, proliferated heaps of oval cells were noted in bothportal and peripheral areas. In the period of carcinomatouschange, oval cells could be seen both outside and inside ofcancer nodes, but most of them were distributed outside.The c-myc gene was expressed negatively in the liver tissueof mice. The quantity of the expression began to increaseat the time of infection of the liver and tended to increasewith the degree of hepatic injury. In the period of cancera-tion, the expression level of c-myc mRNA increased gra-dually. The intervention of uscharidin could not inhibit butdelay the increase of the expression of c-myc mRNA.CONCLUSION: Oval cells are closely related to hepatocar-cinoma cells, which play an important role in the occur-rence and development of hepatocarcinogenesis. Uschari-din can inhibit the occurrence of hepatocarcinogenesis orlocal spreading at the early stage of cancer induction byDAB, but it cannot inhibit the expression of c-myc.

Tissue array for Tp53,C-myc,CCND1 gene over-expression in different tumors

AIM:To rapidly detect molecular alterations in different malignancies and investigate the possible role of Tp53,C-myc,and CCND1 genes in development of tumors in human organs and their adjacent normal tissues,as well as the possible relation between well-and poorly-differentiated tumors.METHODS:A tissue array consisting of seven different tumors was generated.The tissue array included 120 points of esophagus,120 points of stomach,80 points of rectum,60 points of thyroid gland,100 points of mammary gland,80 points of liver,and 80 points of colon.Expressions of Tp53,C-myc,and CCND1 were determined by RNA in situ hybridization.3' terminal digoxin-labeled anti-sense single stranded oligonucleotide and locked nucleic acid modifying probe were used.RESULTS:The expression level of Tp53 gene was higher in six different carcinoma tissue samples than in paracancerous tissue samples with the exception in colon carcinoma tissue samples(P < 0.05).The expression level of CCND1 gene was significantly different in different carcinoma tissue samples with the exception in esophagus and colon carcinoma tissue samples.The expression level of C-myc gene was different in esophagus carcinoma tissue samples(c2 = 18.495,P = 0.000),stomach carcinoma tissue samples(c2 = 23.750,P = 0.000),and thyroid gland tissue samples(c2 = 10.999,P = 0.004).The intensity of signals was also different in different carcinoma tissue samples and paracancerous tissue samples.CONCLUSION:Over-expression of the Tp53,CCND1,and C-myc genes appears to play a role in development of human cancer by regulating the expression of mRNA.Tp53,CCND1 and C-myc genes are significantly correlated with the development of different carcinomas.

Key genes and regulatory networks for diabetic retinopathy based on hypoxia-related genes:a bioinformatics analysis

AIM:To prevent neovascularization in diabetic retinopathy(DR)patients and partially control disease progression.METHODS:Hypoxia-related differentially expressed genes(DEGs)were identified from the GSE60436 and GSE102485 datasets,followed by gene ontology(GO)functional annotation and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway enrichment analysis.Potential candidate drugs were screened using the CMap database.Subsequently,a protein-protein interaction(PPI)network was constructed to identify hypoxia-related hub genes.A nomogram was generated using the rms R package,and the correlation of hub genes was analyzed using the Hmisc R package.The clinical significance of hub genes was validated by comparing their expression levels between disease and normal groups and constructing receiver operating characteristic curve(ROC)curves.Finally,a hypoxia-related miRNA-transcription factor(TF)-Hub gene network was constructed using the NetworkAnalyst online tool.RESULTS:Totally 48 hypoxia-related DEGs and screened 10 potential candidate drugs with interaction relationships to upregulated hypoxia-related genes were identified,such as ruxolitinib,meprylcaine,and deferiprone.In addition,8 hub genes were also identified:glycogen phosphorylase muscle associated(PYGM),glyceraldehyde-3-phosphate dehydrogenase spermatogenic(GAPDHS),enolase 3(ENO3),aldolase fructose-bisphosphate C(ALDOC),phosphoglucomutase 2(PGM2),enolase 2(ENO2),phosphoglycerate mutase 2(PGAM2),and 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 3(PFKFB3).Based on hub gene predictions,the miRNA-TF-Hub gene network revealed complex interactions between 163 miRNAs,77 TFs,and hub genes.The results of ROC showed that the except for GAPDHS,the area under curve(AUC)values of the other 7 hub genes were greater than 0.758,indicating their favorable diagnostic performance.CONCLUSION:PYGM,GAPDHS,ENO3,ALDOC,PGM2,ENO2,PGAM2,and PFKFB3 are hub genes in DR,and hypoxia-related hub genes exhibited favorable diagnostic performance.

RPLP0/TBP are the most stable reference genes for human dental pulp stem cells under osteogenic differentiation

BACKGROUND Validation of the reference gene(RG)stability during experimental analyses is essential for correct quantitative real-time polymerase chain reaction(RT-qPCR)data normalisation.Commonly,in an unreliable way,several studies use genes involved in essential cellular functions[glyceraldehyde-3-phosphate dehydro-genase(GAPDH),18S rRNA,andβ-actin]without paying attention to whether they are suitable for such experimental conditions or the reason for choosing such genes.Furthermore,such studies use only one gene when Minimum Information for Publication of Quantitative Real-Time PCR Experiments guidelines recom-mend two or more genes.It impacts the credibility of these studies and causes dis-tortions in the gene expression findings.For tissue engineering,the accuracy of gene expression drives the best experimental or therapeutical approaches.We cultivated DPSCs under two conditions:Undifferentiated and osteogenic dif-ferentiation,both for 35 d.We evaluated the gene expression of 10 candidates for RGs[ribosomal protein,large,P0(RPLP0),TATA-binding protein(TBP),GAPDH,actin beta(ACTB),tubulin(TUB),aminolevulinic acid synthase 1(ALAS1),tyro-sine 3-monooxygenase/tryptophan 5-monooxygenase activation protein,zeta(YWHAZ),eukaryotic translational elongation factor 1 alpha(EF1a),succinate dehydrogenase complex,subunit A,flavoprotein(SDHA),and beta-2-micro-globulin(B2M)]every 7 d(1,7,14,21,28,and 35 d)by RT-qPCR.The data were analysed by the four main algorithms,ΔCt method,geNorm,NormFinder,and BestKeeper and ranked by the RefFinder method.We subdivided the samples into eight subgroups.RESULTS All of the data sets from clonogenic and osteogenic samples were analysed using the RefFinder algorithm.The final ranking showed RPLP0/TBP as the two most stable RGs and TUB/B2M as the two least stable RGs.Either theΔCt method or NormFinder analysis showed TBP/RPLP0 as the two most stable genes.However,geNorm analysis showed RPLP0/EF1αin the first place.These algorithms’two least stable RGs were B2M/GAPDH.For BestKeeper,ALAS1 was ranked as the most stable RG,and SDHA as the least stable RG.The pair RPLP0/TBP was detected in most subgroups as the most stable RGs,following the RefFinfer ranking.CONCLUSION For the first time,we show that RPLP0/TBP are the most stable RGs,whereas TUB/B2M are unstable RGs for long-term osteogenic differentiation of human DPSCs in traditional monolayers.

Expressions of vascular endothelial growth factor in cirrhotic tissues and their relations to proto-oncogene c-fos, c-myc

Objective: To investigate the significance of vascular endothelial growth factor (VEGF) in the pathogene- sis of liver cirrhosis and the correlation between VEGF and proto-oncogene c-fos and c-myc in cir- rhotic liver. Methods: The proteins of VEGF, c-fos, and c-myc were identified immunohistochemically in each tissue section of 53 cases of liver cirrhosis. The correlations between VEGF, c-fos and c-myc were analyzed. The levels of VEGF protein in different Child gradings were also compared. Results: The proteins of VEGF were more highly ex- pressed in Child A and B patients than in Child C patients and controls. The expressions of both c-fos and c-myc were not statistically significant between VEGF positive and negative patients. Conclusions: The protein level of VEGF can reflect the compensation status of cirrhosis patients and may act as an anti-cirrhotic factor. The proto-oncogene c- fos, c-myc and VEGF may have different mecha- nisms in the course of cirrhosis or hepatic tumorigen- esis.

Comprehensive analysis of the potential pathogenesis of COVID-19 infection and liver cancer

BACKGROUND A growing number of clinical examples suggest that coronavirus disease 2019(COVID-19)appears to have an impact on the treatment of patients with liver cancer compared to the normal population,and the prevalence of COVID-19 is significantly higher in patients with liver cancer.However,this mechanism of action has not been clarified.Gene sets for COVID-19(GSE180226)and liver cancer(GSE87630)were obtained from the Gene Expression Omnibus database.After identifying the common differentially expressed genes(DEGs)of COVID-19 and liver cancer,functional enrichment analysis,protein-protein interaction network construction and scree-ning and analysis of hub genes were performed.Subsequently,the validation of the differential expression of hub genes in the disease was performed and the regulatory network of transcription factors and hub genes was constructed.RESULTS Of 518 common DEGs were obtained by screening for functional analysis.Fifteen hub genes including aurora kinase B,cyclin B2,cell division cycle 20,cell division cycle associated 8,nucleolar and spindle associated protein 1,etc.,were further identified from DEGs using the“cytoHubba”plugin.Functional enrichment analysis of hub genes showed that these hub genes are associated with P53 signalling pathway regulation,cell cycle and other functions,and they may serve as potential molecular markers for COVID-19 and liver cancer.Finally,we selected 10 of the hub genes for in vitro expression validation in liver cancer cells.CONCLUSION Our study reveals a common pathogenesis of liver cancer and COVID-19.These common pathways and key genes may provide new ideas for further mechanistic studies.

The role of tazarotene-induced gene 1 in carcinogenesis:is it a tumor suppressor gene or an oncogene?

Tazarotene-induced gene 1(TIG1)is induced by a derivative of vitamin A and is known to regulate many important biological processes and control the development of cancer.TIG1 is widely expressed in various tissues;yet in many cancer tissues,it is not expressed because of the methylation of its promoter.Additionally,the expression of TIG1 in cancer cells inhibits their growth and invasion,suggesting that TIG1 acts as a tumor suppressor gene.However,in some cancers,poor prognosis is associated with TIG1 expression,indicating its protumor growth characteristics,especially in promoting the invasion of inflammatory breast cancer cells.This review comprehensively summarizes the roles of the TIG1 gene in cancer development and details the mechanisms through which TIG1 regulates cancer development,with the aim of understanding its various roles in cancer development.