Function of apoptosis and expression of the proteins Bcl-2,p53 and C-myc in the development of gastric cancer

INTRODUCTIONIn China ,the incidence and mortality of gastric cancer rank the second among all cancers. Recent development of cancer [1-20].The aim of this study was investigat the insight of apoptosis and bcl-2, p53 and C-myc protein expression in the development of gastric cancer .

Expressions of beta-catenin, APC Protein, C-myc and Cyclin D1 in Ovarian Epithelial Tumor and Their Implication

Objective： To investigate the expressions of beta-catenin, protein APC （adenomatous polyposis coil protein）, c-myc and cyclin D1 and their implication in ovarian epithelial tumor. Methods： Immunohistochemical staining with SP method was conducted to identify the expressions of beta-catenin, APC protein, c-myc and cyclin D1 in ovarian epithelial tumor in 48 cases. Results： The abnormal expression rate of beta-catenin in malignant and borderline ovarian epithelial tumors was higher than that in benign epithelial tumors （P〈0.01）. The expression rates of c-myc and cyclin-D1 in ovarian malignant and borderline epithelial tumors were higher than those in benign epithelial tumors too（P〈0.05）. The prevalence of APC protein positive expression in benign epithelial tumors were significantly greater than that in malignant epithelial tumors （P〈0.05）. A significant negative correlation was found between beta-catenin and APC protein in ovarian epithelial tumors; while a significant positive correlation was found between beta-catenin, c-myc and cyclin-D1 in ovarian epithelial tumor （P〈0.05）. Conclusion： The abnormal expressions of Beta-catenin, APC protein, c-myc and cyclin-D1 might be used to indicate the malignance transform of ovarian epithelial tumors.

EFFECT OF ACTIVE COMPOUNDS ISOLATED FROM PTERIS SEMIPINNATA L ON DNA TOPOISOMERASES AND TYROSINE PROTEIN KINASE AND EXPRESSION OF C-MYC IN LUNG ADENOCARCINOMA CELLS

Objective: To study the effect of active compound 6F and A from Pteris semipinnata L.(PsL) on the activities of DNA topoisomerase (TOPO) I and II, activities of cytosolic and membrane TPK, and expression of oncogene c-myc in lung adenocarcinoma cells. Methods: The effect of compound 6F and A on activities of cytosolic and membrane TPK was measured by scintillation counting; the effect of compound A on expression of oncogene c-myc was determined by flow cytometry indirect fluorimetry. Results: compound 6F and A could inhibit the activities of TOPO I, and they strongly inhibited the TOPO II in 0.01 mg/L and 10.0 mg/L respectively. Compound A slightly inhibited the activities of membrane TPK, but not the cytosolic one. Compound A could inhibit the expression of oncogene c-myc. Conclusion: Topoisomerases are target of compound 6F and A. Compound A could slightly inhibit the activities of TPK, and showed an inhibitory effect on the expression of oncogene c-myc.

Reactive oxygen species-induced activation of Yes-associated protein-1 through the c-Myc pathway is a therapeutic target in hepatocellular carcinoma

BACKGROUND The Hippo signaling pathway regulates organ size by regulating cell proliferation and apoptosis with terminal effectors including Yes-associated protein-1(YAP-1).Dysregulation in Hippo pathway has been proposed as one of the therapeutic targets in hepatocarcinogenesis.The levels of reactive oxygen species(ROS)increase during the progression from early to advanced hepatocellular carcinoma(HCC).AIM To study the activation of YAP-1 by ROS-induced damage in HCC and the involved signaling pathway.METHODS The expression of YAP-1 in HCC cells(Huh-7,HepG2,and SNU-761)was quantified using real-time polymerase chain reaction and immunoblotting.Human HCC cells were treated with H2O2,which is a major component of ROS in living organisms,and with either YAP-1 small interfering RNA(siRNA)or control siRNA.To investigate the role of YAP-1 in HCC cells under oxidative stress,MTS assays were performed.Immunoblotting was performed to evaluate the signaling pathway responsible for the activation of YAP-1.Eighty-eight surgically resected frozen HCC tissue samples and 88 nontumor liver tissue samples were used for gene expression analyses.RESULTS H2O2 treatment increased the mRNA and protein expression of YAP-1 in HCC cells(Huh-7,HepG2,and SNU-761).Suppression of YAP-1 using siRNA transfection resulted in a significant decrease in tumor proliferation during H2O2 treatment both in vitro and in vivo(both P<0.05).The oncogenic action of YAP-1 occurred via the activation of the c-Myc pathway,leading to the upregulation of components of the unfolded protein response(UPR),including 78-kDa glucoseregulated protein and activating transcription factor-6(ATF-6).The YAP-1 mRNA levels in human HCC tissues were upregulated by 2.6-fold compared with those in nontumor tissues(P<0.05)and were positively correlated with the ATF-6 Levels(Pearson’s coefficient=0.299;P<0.05).CONCLUSION This study shows a novel connection between YAP-1 and the UPR through the c-Myc pathway during oxidative stress in HCC.The ROS-induced activation of YAP-1 via the c-Myc pathway,which leads to the activation of the UPR pathway,might be a therapeutic target in HCC.

VARIATION AND SIGNIFICANCE OF C-MYC PROTEIN IN RAT CARDIAC VOLUME-OVERLOAD HYPERTROPHY

Objective To investigate the change of c-myc protein, which was chosen as the response indicator to volume-overload. Methods The time and spatial course of c-myc protein expression on the model of rat cardiac volume-overload hypertrophy was examined by immunohistochemical study. Results The immunohistochemical study indicated the expression of c-myc protein was increased obviously at 4-6 hours (62.73%) than that of control (45.41%, P<0.01) after the volume-overload, then decreased gradually along with development of volume-overload hypertrophy and was decreased extremely at 5 months(r=-0.514,P<0.01).Conclusion There are disorders in the signal transduction pathways governing the hypertrophic response of cardiomyocytes in hypertrophic myocardium. C-myc gene and the product of it may be only the promoter gene of myocardial hypertrophy. Once switching on,c-myc gene and the product of it do not act anymore;While it may be that c-myc gene and the product of it increased following with myocardial hypertrophy, and have not direct relation to the occurrence and development of myocardial hypertrophy.

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.

c-Ha-ras and c-myc antisense oligodeoxynucleotides inhibit the proliferation and DNA synthesis in human gastric carcinoma cell lines

The effects of two antisense oligodeoxynucleotides on the expression of c-Ha-ras proto-oncogene and the growth of human gastric carcinoma cell lines were observed. Synthetic 15-mer directed at the region of the translational initiation site of c-Ha-ras proto-oncogene (ASO-r) greatly inhibited the proliferation (55. 61%,P<0. 05) and DNA synthesis (76. 79%,P<0. 05) of MGc-803 cell line. It also inhibited the proliferation (62. 02%,P<0. 05) and DNA synthesis (76. 78%, P<0. 05) of SGc-7901 cell line. A reduction in intracellular P21 ras protein levels in MGc-803 cell line was observed 6 h after the treatment with ASO-r and maintained over 12 h. Another synthetic 15-mer targeted against the initiation codon and downstream 4 codons of c-myc proto-oncogene (ASOm) inhibited only DNA synthesis of MGc-803 cell line (71. 37%, P<0. 05). The control 15-mer did not inhibit the expression of P21 protein and proliferation of these cell lines. These experiments seemed to provide evidence that ASO-r could be effective in inhibiting the expression of c-Ha-ras proto-oncogene and controlling the growth of human gastric carcinoma cells,and that the over-expression of c-Ha-ras proto-oncogene might mainly be associated with the malignant proliferation of human gastric carcinoma cells.

Anchoring of c-myc on nuclear matrix proteins in process of mouse thymic T lymphocyte proliferation induced by ConA

Isolation and characteriation of functional nudear matrix proteins involved in DNA anchoring and gene expression is one of the major subjects of current nudear matrix research. Southwestern blotting (DNA-protein hybridization) was applied to studying the anchoring of c-myc on the nudear matrix proteins in mouse thymic T lymphocytes. The results showed that c-myc bound to the lamin, p34 and p36 nudear matrix proteins specifically. In the process of mouse thymic PNA T lymphocytes proliferation induced by ConA, the anchoring of c-myc on p34 and p36 nudear matrix proteins changed dynamically.

Effects of invigorating-spleen and anticancer prescription on extracellular signal-regulated kinase/mitogen-activated protein kinase signaling pathway in colon cancer mice model

BACKGROUND Colon cancer(CC)is one of the most common malignant tumors in the gastrointestinal system.Overall,CC had the third highest incidence but the second highest mortality rate globally in 2020.Nowadays,CC is mainly treated with capecitabine chemotherapy regimen,supplemented by radiotherapy,immunotherapy and targeted therapy,but there are still limitations,so Chinese medicine plays an important role.AIM To investigate the effects of invigorating-spleen and anticancer prescription(ISAP)on body weight,tumor inhibition rate and expression levels of proteins in extracellular-signal-regulated kinase(ERK)/mitogen-activated protein kinase(MAPK)signaling pathway in CC mice model.METHODS The CC mice model were established and the mice were randomly divided into 5 groups,including the control group,capecitabine group,the low-dose,mediumdose and high-dose groups of ISAP,with 8 mice in each group,respectively.After 2 weeks of intervention,the body weight and tumor inhibition rate of mice were observed,and the expression of RAS,ERK,phosphorylated ERK(p-ERK),C-MYC and matrix metalloproteinase 2(MMP2)proteins in the tissues of tumors were detected.RESULTS Compared with the control group,the differences of body weight before and after treatment was much smaller in the groups of ISAP,with the smallest difference in the high-dose group of ISAP,while the capecitabine group had the greatest difference,indicating ISAP had a significant inhibiting effect on the growth of transplanted tumor in mice.The expression of RAS protein was decreased in the low-and medium-dose groups of ISAP,and the change of p-ERK was significant in the medium-and high-dose groups of ISAP.MMP2 protein expression was significantly decreased in both the low-dose and medium-dose groups of ISAP.There were no significant changes in ERK in the ISAP group compared to the capecitabine group,while RAS,MMP2,and C-MYC protein expression were reduced in the ISAP group.The expression level of C-MYC protein decreased after treated with ISAP,and the decrease was the most significant in the medium-dose group of ISAP.CONCLUSION ISAP has a potential inhibiting effect on transplanted tumor in mice,and could maintain the general conditions,physical strength and body weight of mice.The expression levels of RAS,p-ERK,MMP2 and c-myc were also decreased to a certain extent.By inhibiting the expression of upstream proteins,the expression levels of downstream proteins in ERK/MAPK signaling pathway were significantly decreased.Therefore,it can be concluded that ISAP may exert an anti-tumor effect by blocking the ERK/MAPK signaling pathway and inhibiting the expression of MMP2 and c-myc proteins.

CIP2A与肿瘤关系的研究进展

蛋白磷酸酶2A（protein phosphatase 2A,PP2A）的癌性抑制因子（cancerous inhibitor of protein phosphatase 2A,CIP2A）,又名KIAA1524或p90,是最近被鉴别出的一种人类癌蛋白,多项研究表明,CIP2A能够直接与癌转录因子c-Myc蛋白相互作用,抑制PP2A对其丝氨酸62位（S62）的去磷酸化作用,从而抑制了细胞内c-Myc蛋白的水解,稳定了其蛋白表达水平。

Effect of heparin on apoptosis in human nasopharyngeal carcinoma CNE2 cells

In order to study the mechanism of the effect of heparin on apoptosis in carcinoma cells, the nasopharyngeal carcinoma cell line CNE2 was used to identify the effect of heparin on apoptosis associated with the expression of c-myc, bax, bcl-2 proteins by use of Hoechst 33258 staining, terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL), agarose gel electrophoresis, and flow cytometry, as well as Western blot analysis. The results showed that heparin induced apoptosis of CNE2 cells including the morphologic changes such as reduction in the volume, and the nuclear chromatin condensation, as well as the 'ladder pattern' revealed by agarose gel electrophoresis of DNA in a concentration-dependent manner. The number of TUNEL-positive cells was dramatically increased to 33.6+/-1.2% from 2.8+/-0.3% by treatment with heparin in different concentrations (10 to approximately 40 kU/L). The apoptotic index was increased to 32.5% from 3.5% by detecting SubG1 peaks on flow cytometry. Western blot analysis showed that levels of bcl-2, bax and c-myc were significantly overexpressed by treatment with the increase of heparin concentrations. These results suggest that heparin induces apoptosis of CNE2 cells, which may be regulated by differential expression of apoptosis-related genes.

Pathophysiological roles of Pim-3 kinase in pancreatic cancer development and progression

Pim-3 is a member of the provirus integration site for Moloney murine leukemia virus(Pim)family proteins that exhibit serine/threonine kinase activity.Similar to the other Pim kinases(Pim-1 and Pim-2),Pim-3 is involved in many cellular processes,including cell proliferation,survival,and protein synthesis.Although Pim-3is expressed in normal vital organs,it is overexpressed particularly in tumor tissues of endoderm-derived organs,including the liver,pancreas,and colon.Silencing of Pim-3 expression can retard in vitro cell proliferation of hepatocellular,pancreatic,and colon carcinoma cell lines by promoting cell apoptosis.Pim-3 lacks the regulatory domains similarly as Pim-1 and Pim-2 lack,and therefore,Pim-3 can exhibit its kinase activity once it is expressed.Pim-3 expression is regulated at transcriptional and post-transcriptional levels by transcription factors(e.g.,Ets-1)and post-translational modifiers(e.g.,translationally-controlled tumor protein),respectively.Pim-3 could promote growth and angiogenesis of human pancreatic cancer cells in vivo in an orthotopic nude mouse model.Furthermore,a Pim-3 kinase inhibitor inhibited cell proliferation when human pancreatic cancer cells were injected into nude mice,without inducing any major adverse effects.Thus,Pim-3 kinase may serve as a novel molecular target for developing targeting drugs against pancreatic and other types of cancer.

Regulating Effects of Herb Cake-partitioned Moxibustion on the Expression of p53 and C-myc Protein in Rats with Ulcerative Colitis

Objective： To investigate the mechanism of herb cake-partitioned moxibustion treating ulcerative colitis （UC） from the relationship between expression of p53 and C-myc protein, and morbidity of UC. Methods： Rats model of UC was made with immune methods and local stimulation. Forty SD rats were divided into normal, model, herb cake-partitioned, and mild moxibustion group by a random number table, 10 rats in each group. Hanging moxibustion in the mild moxibustion group was applied to Tianshu （ST 25） and Qihai （CV 6） for 10 rain. Two moxa cones of herb cake-partitioned moxibustion were applied to the same acupoints respectively, in the herb cake-partitioned moxibustion group. Expression of p53 and C-myc protein was measured with immuno- histochemistical method in the colonic tissue of rats with UC. Results： Postive area, strength, and the immunohistochemistry index of the expression of p53 and C-myc protein were found more in the model rats than those in the normal rats （P〈0.01）, whereas less in the herb cake-partitioned moxibustion and mild moxibustion groups than those in the model group （P〈0.01）. Conclusion： p53 and C-myc play important roles in the morbidity and development of UC, and herb cake-partitioned moxibustion could regulate the expression of p53 and C-myc protein in the colonic tissue of UC rats.

EXPRESSION OF c－myc GENE AND BIOSYNTHESIS OF BIOLOGICAL MACROMOLECULES IN ANTISENSE TRANSFECTANT HL_（60）~R－9

The recombinant plasmid PGC was constructed for transcription unit of c-myc gene with diorientation in vitro, to make RNA probes for detection of c-myc mRNA and antisence RNA expression of tranfectant HL-9,which was obtained from HL60 cells transfected with inducible c-myc antisense RNA expression plasmid. The results from HL-9 cells induced by Cd2+ indicated that expression of c-myc antisense RNA increased with Cd2+ concentration and exposure time, while c-myc mRNA expression progressively reduced. Using immunohistochemical technique no c-myc P62 protein expression was detected. The incorporation of 3H-TdR, 3H-UR and 3H-Leu revealed significant suppression of DNA, RNA and protein biosynthesis. It is suggested that the reversion changes previously reported in malignant Phenotypes of HL-9 cells and the inhibition of macromolecular biosynthesis mentioned above were associated with the blockade of c-myc gene expression by its antisense RNA.

Effects of Radix Salviae Miltiorrhizae on Proliferation,Apoptosis and c-myc Protein Expression of Fibroblast in Culture of Kindney with Lupus Nephritis

Objectiv:To observe the effects ofRadix Salviae Miltiorrhizae (SM) on humanfibroblast in culture of kidney with lupus nephritis (LN ). Methods: Fibroblasts wereisolated from culture of kidney biopsy of LN patients, and effect of SM on 3H-TdR incorporated rate of fibroblasts was observed. Theapoptosis and c-myc expression were detectedin the same time by flow cytometry.Results:SM could inhibit the proliferation of fibrolast,and promote the programmed cell deaththrough upregulate c-myc protein expression inhuman renal fibroblasts. Conclusions: Longterm administration of SM in large dosagecould be effective on interstial fibrosis of LN,so that to prevent or reduce the scar tissue for-mation and teatrd the occurrence of uremia.

F框/WD40域蛋白7和c-myc蛋白在食管鳞状细胞癌中的表达及意义

泛素蛋白酶体途径成员的异常表达或突变可导致包括恶性肿瘤在内的多种疾病的发生[1].作为泛素蛋白酶体途径的重要识别因子之一,F框/WD40域蛋白7（F-box and WD-40 domain protein 7,FBXW7）作用的许多底物都是癌基因,如c-mye、细胞周期素E、c-jun和Notch等都是通过FBXW7介导的泛素蛋白酶体途径进行降解的[2-5].近年研究发现,FBXW7在多种肿瘤中的表达均有不同程度的缺失.

Effects of External Application of Chinese Medicine on Diabetic Ulcers and the Expressions of β-catenin,c-myc and K6

Objective：To observe the clinical efficacy of Chinese medicine（CM） treatment of Hongyou Ointment（红油膏） and Shengji Powder（生肌散） on diabetic ulcers,and to observe the influence of CM treatment on the expressions of proteins associated with the Wnt signaling pathway,such asβ-catenin,c-myc and K6.Methods：sixty-two patients fitting the registration standards were randomly divided into the CM group（31 patients） and the Western medicine（WM） group（31 patients） by a random number table.The patients in the CM group were treated with Hongyou Ointment and Shengji Powder externally.The patients in the WM group were treated with mupirocin ointment,growth factor（bFGF）,and Vaseline gauze for external use and with basic therapies.Wound-healing time and four-week healing rate were recorded.The wounds were measured by digital photography and ImageJ software.Skin biopsies were obtained from 24 patients before CM treatment and 20 patients after CM treatment.Immunohistochemical tests and semi-quantitative imaging with NIH ImageJ 1.42 software were used to analyze the changes in protein expression ofβ-catenin,c-myc,and K6.Results：Fifty-three patients completed the trial;four patients in the CM treatment group and five patients in the WM group dropped out.Among them,four were dissatisfied with the treatment process,two could not continue because of their jobs,two failed to complete the course of follow-up appointments,and one was diagnosed with squamous cell carcinoma during treatment.The comparison of ulcer healing rates between the two groups showed insignificant differences（P=0.77）.The ulcer healing rates were 33.33%（9/27） in the CM group and 26.92%（7/26） in the WM group.However,the effective rate was significantly higher in the CM group（81.48%,22/27） than in the WM group（57.69%,15/26,P=0.04）.The mean wound healing time was shorter in the CM group（22.71±5.46 days） than in the WM group（26.56±7.56 days,P=0.04）.CM treatment was well tolerated,and there was no withdrawal due to adverse reactions.Immunohistochemical analysis in the refractory wound indicated higher expressions ofβ-catenin,c-myc and K6 compared with the normal skin.β-catenin was abnormally expressed in the nuclei of the keratinocytes and fibroblasts at the wound margins,and the expressions of c-myc and K6 were highly expressed in the full hyperplastic epidermis,especially in the granular layer（P0.05）.The expressions of these proteins decreased after CM treatment.The expression levels ofβ-catenin,c-myc,and K6 proteins before and after the treatment were 101.88±10.76 vs.140.42±8.45;113.27±16.75 vs.153.79±8.32; 90.39±11.07 vs.151.29±7.39,respectively.Conclusions：CM treatment using Hongyou Ointment and Shengji Powder was efficient in the management of diabetic skin ulcers.The mechanism of action might be related to the inhibition of the Wnt signaling pathway.

Abnormal expression of c-Myc in human bronchial epithelial cells malignantly transformed by anti-BPDE

Anti-benzo[a]pyrene-7,8-diol-9,10-epoxide(anti-BPDE)is a metabolite of benzo[a]pyrene(B[a]P)and acts as a potent mutagen in mammalian systems.However,molecular mechanisms related to anti-BPDE-induced carcinogenesis are poorly understood.Here,we investigated the expression of proto-oncogene c-myc in human bronchial epithelial cells(16HBE-T)transformed by exposure to anti-BPDE.The levels of mRNA and pro-tein of c-Myc were examined in the 16HBE-T and vehicle-treated control cells(16HBE-N)by using different meth-ods respectively,including reverse transcriptase-polymer-ase chain reaction(RT-PCR),quantitative real-time PCR(Q-PCR),western blot and immunocytochemical meth-ods.The level of c-myc mRNA appeared to be signifi-cantly increased in 16HBE-T,as compared with those of the 16HBE-N.Likewise,the expression of c-Myc protein was significantly enhanced as compared with those of the control cells.Moreover,the localization of c-Myc protein shows mainly nuclear staining in 16HBE-T.In conclu-sion,the abnormal expression of c-Myc was present in anti-BPDE malignantly transformed 16HBE cells,which may be involved in the carcinogenesis molecular mech-anism of anti-BPDE.

Effect of Emodin on Biological Behavior of Fibroblasts in Lupus Nephritis

Objective: To observe the effect of emodin on the biological behavior of human fibroblasts (FB) in culture of kidney in patients with lupus nephritis (LN).Methods: FB were isolated from kidney culture of LN patients, and the effect of emodin on3H-TdR incorporated rate of FB was observed. The apoptosis and c-myc gene expression were detected in the same way by flow cytometry.Results: Emodin could markedly inhibit the proliferation of human kidney FB, and inducing cell apoptosis through up-regulating c-myc gene expression in human renal FB.Conclusion: Emodin can inhibit proliferation and promote apoptosis of FB, which may be important in ameliorating interstitial fibrosis, and thus improve prognosis of LN.