Expression of E-selectin, integrinβ_1 and immunoglobulin superfamily member in human gastric carcinoma cells and its clinicopathologic significance

AIM： To study the expression levels of E-selectin, integrin β1 and immunoglobulin supperfamily memberintercellular adhesion molecule-1 （ICAM-1） in human gastric carcinoma cells, and to explore the relationship between these three kinds of cell adhesion molecules and gastric carcinoma. METHODS： The serum contents of E-selectin, integrin β1 and ICAM-1 were detected by enzyme-linked immunosorbent assay （ELISA）, in 47 healthy individuals （control group） and in 57 patients with gastric carcinoma （gastric carcinoma group） respectively prior to operation and 7 d after operation. RESULTS： The serum E-selectin, ECAM-1 and integrin β1 were found to be expressed in both control and gastric carcinoma groups. However, they were highly expressed in patients with gastric carcinoma patients before operation or with unresectable tumours. The expression levels of ICAM-1 and integrin β1 were significantly higher in gastric carcinoma patients than in controls （P 〈 0.01）. A comparison of the E-selectin levels between the two groups showed statistically insignificant differnce （P = 0.64）. In addition, the expression levels were all decreased substantially in the postoperative patients subjected to radical resection of the tumours, indicating that the high level expressions of these compounds might be the important factor for predicting the prognosis of these patients. CONCLUSION： Serum E-selectin, ICAM-1 and integrin β1 expression levels are probably related to the metastasis and relapse of gastric cancer.

Low intensity ultrasound-induced apoptosis in human gastric carcinoma cells

AIM： To investigate the low intensity ultrasound （US）- induced apoptosis in human gastric carcinoma cells and its potential mechanism and to suggest a new therapeutic approach to gastric carcinoma. METHODS： Human SGC-7901 gastric carcinoma cells were cultured in vitro and irradiated by low intensity US for 10 min at different intensities with different incubation times after irradiation. Morphologic changes were examined under microscope with trypan blue staining and then the percentage of early apoptotic cells was detected by flow cytometry （FCM） with double staining of fiuorescein isothiocyanate （FITC）- Annexin V/propidium iodide （PI）. Two-dimensional electrophoresis （2DE） was used to get the protein profile and some proteins differently expressed after US irradiation were identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry （MALDI-TOF-MS）. Functional analysis was performed to investigate the mechanism of US-induced cell apoptosis. RESULTS： The percentage of apoptotic cells increased about 10% after US irradiation （12.0 W/cm^2, 12 h culture）, The percentage of early apoptosis and secondary necrosis in the US-irradiated cells increased with the increased US intensity. Moreover, apoptotic cells increased with the increased culture time after US irradiation and reached its maximum at about 12 h.Several new proteins appeared after US irradiation and were up or down regulated more than 2 times. Some heat shock proteins （HSPs） were found to be associated with the signal process simulating the apoptosis of cells. CONCLUSION： Low intensity US could induce apoptosis in human gastric carcinoma cells. US-induced apoptosis is related to US intensity/culture time. US-induced apoptosis may be caspases-dependent and endoplasmic reticulum （ER） stress-triggered apoptosis may also contribute to it. Proteomic experimental system is useful in finding the protein alteration in carcinoma cells after US irradiation, helping to develop a new cancer therapy.

Quercetin exerts anti-inflammatory effects via inhibiting tumor necrosis factor-α-induced matrix metalloproteinase-9 expression in normal human gastric epithelial cells

BACKGROUND Gastric injury is the most common digestive system disease worldwide and involves inflammation,which can lead to gastric ulcer or gastric cancer(GC).Matrix metallopeptidase-9[MMP-9(gelatinase-B)]plays an important role in inflammation and GC progression.Quercetin and quercetin-rich diets represent potential food supplements and a source of medications for treating gastric injury given their anti-inflammatory activities.However,the effects and mechanisms of action of quercetin on human chronic gastritis and whether quercetin can relieve symptoms remain unclear.AIM To assess whether tumor necrosis factor-α(TNF-α)-induced MMP-9 expression mediates the anti-inflammatory effects of quercetin in normal human gastric mucosal epithelial cells.METHODS The normal human gastric mucosa epithelial cell line GES-1 was used to establish a normal human gastric epithelial cell model of TNF-α-induced MMP-9 protein overexpression to evaluate the antiinflammatory effects of quercetin.The cell counting Kit-8 assay was used to evaluate the effects of varying quercetin doses on cell viability in the normal GES-1 cell line.Cell migration was measured using Transwell assay.The expression of proto-oncogene tyrosine-protein kinase Src(cSrc),phospho(p)-c-Src,extracellular-signal-regulated kinase 2(ERK2),p-ERK1/2,c-Fos,p-c-Fos,nuclear factor kappa B(NF-κB/p65),and p-p65 and the effects of their inhibitors were examined using Western blot analysis and measurement of luciferase activity.p65 expression was detected by immunofluorescence.MMP-9 m RNA and protein levels were measured by quantitative reverse transcription polymerase chain reaction(q RT–PCR)and gelatin zymography,respectively.RESULTS q RT-PCR and gelatin zymography showed that TNF-αinduced MMP-9 m RNA and protein expression in a dose-and time-dependent manner.These effects were reduced by the pretreatment of GES-1 cells with quercetin or a TNF-αantagonist(TNFR inhibitor)in a dose-and timedependent manner.Quercetin and TNF-αantagonists decreased the TNF-α-induced phosphorylation of c-Src,ERK1/2,c-Fos,and p65 in a dose-and time-dependent manner.Quercetin,TNF-αantagonist,PP1,U0126,and tanshinone IIA(TSIIA)reduced TNF-α-induced c-Fos phosphorylation and AP-1–Luciferase(Luc)activity in a dose-and time-dependent manner.Pretreatment with quercetin,TNF-αantagonist,PP1,U0126,or Bay 11-7082 reduced TNF-α-induced p65 phosphorylation and translocation and p65–Luc activity in a dose-and timedependent manner.TNF-αsignificantly increased GES-1 cell migration,and these results were reduced by pretreatment with quercetin or a TNF-αantagonist.CONCLUSION Quercetin significantly downregulates TNF-α-induced MMP-9 expression in GES-1 cells via the TNFR-c-Src–ERK1/2 and c-Fos or NF-κB pathways.

Inhibitory effect of Fuzheng Yiliuyin in combination with chemotherapeutics on human gastric carcinoma cell strain

AIM： To study the inhibitory effects of Fuzheng Yiliuyin （Decoction for Suppressing Tumors by Strengthening the Body Resistance） in combination with chemotherapeutics on human gastric carcinoma cell strain. METHODS： Fuzheng Yiliuyin （ZY） combined with various kinds of chemotherapeutics was put into two kinds of cultivated human gastric carcinoma cell strains, then its inhibitory effects on human gastric carcinoma cell strains were determind by the MTT method. Flow cytorneter was used to assay the apoptosis rate, and the ultrastructure of gastric carcinoma cells was observed under transmission electron microscope. RESULTS： Obvious apoptosis was seen in gastric carcinoma cells after treatment with ZY for 72 h. ZY and chemical drugs had synergistic inhibition effects on the cultivated gastric carcinoma cells, but the effects were different on various cell strains. The inhibitory effects of ZY could be strengthened by cytotoxic action and apoptosis. ZY combined with tluorouracil, etoposide and cisplatin （EFP） chemotherapeutics had better inhibitory effects on SGC-7901, while ZY combined with EFP or with DDP chemotherapeutics had better inhibitory effects than other drugs on MGC-803. CONCLUSION： ZY induces apoptosis and inhibits the growth of gastric carcinoma cells. ZY has the synergistic function of chemotherapeutics.

Effects of Spinach Powder Fat-Soluble Extract on Proliferation of Human Gastric Adenocarcinoma Cells

Four kinds of assays were used to study the effect of a fat-soluble extract of spinach powder (SPFE) on the proliferation of human gastric adenocareinoma cell line (SGC-7901) in vitro.These studies included: (Ⅰ) cell growth assay, (Ⅱ) colony forming assay, (Ⅲ) MTT colorimetric assay, and (Ⅳ) 3H-TdR incorporation assay. The concentrations of SPFE expressed as the level of β-carotene in the medium were 2×10-8, 2×10-7 and 2×10-6 mol/L β-carotene in assays (Ⅰ)～(Ⅲ), but 4×10- 8, 4×10-7 and 4×10-6 mol/L β-caretene in assay (Ⅳ) respectively. The results indicated that SPFE inhibited the prolifendion and colony forming ability of SGC-7901 cells. And in MTT assay, SPFE inhibited the viability of SGC7901 cells, but no inhibitory effect of SPFE was observed on the viability of lymphocytes in peripheral blood of healthy people. Finally, in the 3H-TdR incorporation test, both SPFE and β-carotene showed significant inhibitory effects on DNA synthesis in SGC-7901 cells, but SPFE was more effective than β-carotene.

Paris Saponin Ⅰ Induces G_2/M Cell Cycle Arrest and Apoptosis in Human Gastric Carcinoma SGC7901 Cells

The aim of this study was to investigate the effect of Paris saponin I （PSI ） on human gastric carcinoma cell growth and apoptosis and to explore the potential mechanisms. The proliferation of SGC7901 cells was monitored by the MTT cell viability assay, while the nuclear morphology of apoptotic cells was assessed by Hoechst 33258 staining. Flow cytometry was performed to analyze the cell cycle progression of propidium iodide （PI）-stained SGC7901 cells and the apoptotic rate of annexin V/PI-stained ceils. Western blotting was used to examine the expression of several cell cycle proteins, including cyclin 131 and Cdkl, and the apoptosis-regulated proteins Bcl-2, Bax, cytochrome c, procaspase-9, and procaspase-3. The MTT assay demonstrated that PSI could induce significant dose- and time-dependent inhibition of SGC7901 cell proliferation. Marked morphological changes, including condensation of chromatin, nuclear fragmentation and apoptotic bodies were clearly shown on Hoechst 33258 staining. PS I treatment also resulted in the disruption of the cell cycle at Gz/M and the induction of apoptosis. Following PSI treatment, the cell cycle-related proteins cyclin B 1 and Cdkl were down- regulated. Expression of the pro-apoptotic protein Bax was increased, while anti-apoptotic protein Bcl-2 decreased. PSI treatment resulted in elevated cytoplasmic cytochrome c and activation of the apoptotic proteases caspase-9 and caspase-3. These data indicate that PS I acts as an inhibitor of proliferation in SGC7901 cells by inducing cell cycle arrest and mitochondria-dependent apoptosis. PSI is a potential therapeutic agent against human gastric carcinoma.

Growth-inhibiting and Apoptosis-inducing Effects of Tanshinone ⅡA on Human Gastric Carcinoma Cells

To explore the effects of Tanshinone Ⅱ A on the proliferation, apoptosis and gene expression of p53 and bcl-2 in human gastric carcinoma MKN-45 cells. Cell count and MTT assay were used to study the proliferation-inhibiting effect of Tanshinone Ⅱ A on MKN-45 cells. The effect of Tanshinone Ⅱ A on the cell cycle and apoptosis of MKN-45 cells were examined by propidium iodide （PI） staining and flow cytometry. Semi-quantitative RT-PCR was used to further verify the ex- pression of p53 and bcl-2 gene after exposure to Tanshinone Ⅱ A in MKN-45 cells. The results showed that Tanshinone Ⅱ A significantly inhibited the growth and proliferation of MKN-45 cells in a dose- and time-dependent manner （P〈0.05）. Tanshinone Ⅱ A arrested MKN-45 cells in G2/M phase which led to an obvious accumulation of G2/M phase cells while decreased number of Go/G1 phase cells. This resulted in apoptosis of MKN-45 cells and the apoptosis rate was as high as 43.91% after treatment with 2.0 lag/mL Tanshinone Ⅱ A for 96 h. It was also found that Tanshinone Ⅱ A up-regulated expression of p53 gene and down-regulated expression of bcl-2 gene. The cytostatic and antiproliferative effect of Tanshinone Ⅱ A makes it a promising anticancer agent for the treatment of gastric carcinoma.

THE DIFFERENTIATION OF HUMAN GASTRIC ADENOCAR-CINOMA CELL LINE MGc80-3 INDUCED BY DIBUTYRYL cAMP IN VITRO

For providing some experimental basis in establishing malignant phenotypic reversed indexes of gastric carcinoma cells, human gastric adenocar-cinoma cell line MGc80-3 was induced by dBcAMP in vitro to appraise the effect of gastric carcinoma cell differentiation by chemical inducers.Under light microscope, MGc80-3 cells, after treated with 1 mM dBcAMP, tended to be flat and disperse, and their volume gradually enlarged, with their uncleus relatively smaller and their shape rather regular. Morphological changes, like norma differentiated epithelial cells, were observed. The cells attached firmly, grew slowly, their growth curve showed inhibitory rate amounted to 52.87%, and cellular division exponent displayed their peak value 1.5 times less than that of MGc80-3 cells. It was clear that dBcAMP could effectively inhibit the multiplication activity of MGc80-3 cells. After dBcAMP treatment, remarkable changes of cell surface charges was indicated by cell electrophoresis, the ratio dropped to 3.043 from 3.988, and their re-tardant ratio reached up to 31.2%. cAMP content in cells after this treatment, detected by cAMP and cGMP radioimmunoassay, was enhanced by 2.42 times, and cAMP/cGMP ratio, by 1.73 times. Thus, cAMP level within MGc80-3 cells was raised obviously by dBcAMP. Heterotransplantation experiments showed that tuntorigenic rate of MGc80-5 cells (transplanted subcutaneously to BALB/c mice) amounted to 100%, and that of the cells after this treatment was only 5.6%. Their tumorigenic ability was extremely reduced.These results confirmed that dBcAMP was able to change malignant phenotypic characteristics of MGc80-3 cells and produce a reversed alteration: Thus, it has a remarkable inductive effect in differentiating gastric carcinoma cells. All these characteristics were also considered as the reference indexes in appraising reversed effect for the homologous cancer cells.

CHEMOSENSITIVITY OF MGc80-3 HUMAN GASTRIC ADENOCARCINOMA CELLS AND ITS CLINICAL SIGNIFICANCE

In the present study, the chemosensitivity of MGc80-3 human gastric adenocarcinoma cells was determined by means of colony-forming assay and the in vitro activities of 10 anticancer drugs were examined on the basis of the clinically achievable peak plasma drug concentration. The results showed that MGc80-3 cells were most sensitive to mitomyc'n C, adriamycin and 5-fluorouracil, being consistent with the response noted in clinical gastric cancer. This cell line may retain its original drug sensitivity and may be useful in screening for new compounds with activity against this disease.

INTERACTIONS BETWEEN THE HUMAN GASTRIC CARCINOMA CELL AND THE HUMAN VASCULAR ENDOTHELIAL CELL

Objective To definite the interactions between the human gastric carcinoma cell and the human vascular endothelial cell during the establishment and maintenance of the tumor vascular system and the tumor hematogenous metastasis.Methods We prepared the conditioned mediums of each cell so as to study the effect of the conditioned medium on itself or others by MTT colorimetry. The comprehensive effect of interactions between two cells was determined by stratified transfilter co culture or direct contact co culture.Results The conditioned medium of human gastric carcinoma cell can stimulate the proliferation of the human vascular endothelial cell, but the CM of HVEC can inhibit the growth of HGCC. Both kinds of cells can inhibit the growth of itself. The ultimate comprehensive effect of the interactions between two kinds of cells was increase of total cell numbers.Conclusion There exist the complicated interactions between the human gastric carcinoma cell and the human vascular endothelial cell during the tumor angiogenesis and the tumor hematogenous metastasis. The ultimate comprehensive effect of the interactions is increase of total cells numbers and tumor volume.

DIFFERENCES IN EXPRESSION AND REGULATION BETWEEN TRANSFORMED CELLS OF THE HUMAN GASTRIC CARCINOMA ONCOGENE Ha-ras AND THE UNTRANSFORMED PARENT CELLS

An Ha-ras oncogene was isolated from a cell line of gastric carcinoma called BGE-823 in order to elucidate genetic control and the influence of DNA sequences. The oncogene was cloned and identified as a single nucleotide substitution of thymine for guanine in the 12th codon through the sequencing of its first axon. We compared the differences of expression and regulation between the transformed Ha-ras cells and untransformed parent cells. Data indicated that the expression of Ha-ras in the transformed cells was five-fold higher than in the untransformed cells and that the Ha-ras gene in the former was hypersensitive toward DNase I. In addition, a nuclear protein of 35 kilodaltons bound strongly to the 2.5 Kb fragment located upstream of the 6.6 Kb Ha-ras gene and contained a CC rich region. These results suggest that there might be another mechanism of activation for the ras gene besides point mutation.

The Effect of Sodium Nitrite on Induction of Apoptosis in Human Gastric Adenocarcinoma Epithelia (AGS) Cells

To examine the cytocidal effect of sodium nitrite on the cancer cell, we subjected human gastric adenocarcinoma epithelia (AGS) cells to various experimentation following exposure to sodium nitrite, and measured the resulting changes in the levels of cell death, lactate dehydrogenase (LDH) release, and caspase-3, -6, -8, and -9 activities. Our data revealed that, in AGS cells, treatment with ≥6.25 mM sodium nitrite for 8 h resulted in an obvious increase in cell death. LDH release was also markedly increased following sodium nitrite treatment, but at a concentration of ≥6.25 mM for 24 h. This increasing trend showed a positive correlation (r = 0.9564, P < 0.05). In addition, we detected pronounced increases in caspase activities with various concentrations of sodium nitrite: caspase-3 at ≥25 mM for 1 h, ≥12.5 mM for 3 h and 6 h;caspase-9 at 50 mM for 1 h and 3 h, and ≥6.25 mM for 6 h;and caspase-6 at 50 mM for 1 h and 3 h. We did not however, detect any observable increase in the activity of caspase-8 following sodium nitrite treatment at any concentration or for any duration of treatment in this study. This data demonstrates that, in AGS cells, higher concentrations or longer durations of treatment with sodium nitrite could exhibit a cytocidal effect, and that sodium nitrite could induce apoptosis via activation of the caspase-9, caspase-3 cascade (intrinsic pathway) and caspase-6.

Inhibitory effects of dobutamine on human gastric adenocarcinoma

AIM: To explore the inhibitory effects of dobutamine on gastric adenocarcinoma cells.

Aberrant expression of nuclear matrix proteins during HMBA-induced differentiation of gastric cancer cells

AIM: To investigate the aberrant expression of nuclear matrix proteins in human gastric cancer cells before and after hexamethylene bisacetamide (HMBA) treatment.METHODS: Proteomics analysis of differential nuclear matrix proteins was performed by two dimensional electrophoresis polyacrylamide gel electrophoresis and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry.The expression levels of three nuclear matrix proteins were further confirmed by Western blotting and their locations in nuclear matrix filament were observed by quantum dots-based immunofluorescence.RESULTS: Proteomics analysis showed that 43 protein spots were significantly changed due to HMBA treatment.Fifteen proteins were identified in the HMBAinduced differentiation of gastric tumor cells.Eight proteins spots were down-regulated while seven were up-regulated.Among these proteins,prohibitin,nucleophosmin and hnRNP A2/B1 were significantly decreased in HMBA-treated human gastric cancer cells,and their locations in nuclear matrix were altered by HMBA.Our results proved the alteration of specific nuclear matrix proteins during the differentiation of human gastric cancer cells.And the aberrant expressions of nuclear matrix proteins were of significance in revealing the regulatory mechanism of tumor cell proliferation and differentiation.CONCLUSION: The aberrant expressions and intracellular redistributions of nuclear matrix proteins before and after HMBA treatment indicated that nuclear matrix proteins play a pivotal role in the differentiation of gastric cancer cells.

Human papillomavirus DNA and P16～(INK4A) expression in concurrent esophageal and gastric cardia cancers

AIM:To investigate the relationship between human papillomavirus (HPV) infection and concurrent esophagus and gastric cardia cancer from the same patient (CC) and examine the significance of P16 INK4A protein expression.METHODS:Polymerase chain reaction was used to detect the presence of HPV type16 (HPV16).The expression of P16 INK4A protein was detected using immunohistochemistry.RESULTS:Among the CC specimens,HPV16-DNA was found in eight cases of esophageal squamous cell carcinoma (ESCC) and five cases of gastric cardia adenocarcinoma (GCA),respectively (47% vs 29%),and two of both ESCC and GCA.P16 INK4A was highly expressed in both ESCC and GCA.In the HPV-associated positive CC,higher P16 INK4A expression was observed in the GCA than in the ESCC (75% vs 25%,P < 0.05).CONCLUSION:HPV16 as a correlated risk factor may play an important role in the development of ESCC and GCA.P16 INK4A may be a screening index in the HPVassociated carcinoma of gastric cardia.

New NCI-N87-derived human gastric epithelial line after human telomerase catalytic subunit over-expression

AIM:To establish a cellular model correctly mimicking the gastric epithelium to overcome the limitation in the study of Helicobacter pylori(H.pylori) infection.METHODS:Aiming to overcome this limitation,clones of the heterogenic cancer-derived NCI-N87 cell line were isolated,by stably-transducing it with the human telomerase reverse-transcriptase(h TERT) catalytic subunit gene.The clones were first characterized regarding their cell growth pattern and phenotype.For that we measured the clones' adherence properties,expression of cell-cell junctions' markers(ZO-1 and E-cadherin) and ability to generate a sustained transepithelial electrical resistance.The gastric properties of the clones,concerning expression of mucins,zymogens and glycan contents,were then evaluated by haematoxylin and eosin staining,Periodic acid Schiff(PAS) and PAS/Alcian Blue-staining,immunocytochemistry and Western blot.In addition,we assessed the usefulness of the h TERT-expressing gastric cell line for H.pylori research,by performing co-culture assays and measuring the IL-8 secretion,by ELISA,upon infection with two H.pylori strains differing in virulence.RESULTS:Compared with the parental cell line,themost promising NCI-hT ERT-derived clones(CL5 and CL6) were composed of cells with homogenous phenotype,presented higher relative telomerase activities,better adhesion properties,ability to be maintained in culture for longer periods after confluency,and were more efficient in PAS-reactive mucins secretion.Both clones were shown to produce high amounts of MUC1,MUC2 and MUC13.NCI-hT ERT-CL5 mucins were shown to be decorated with blood group H type 2(BG-H),Lewis-x(Lex),Ley and Lea and,in a less extent,with BG-A antigens,but the former two antigens were not detected in the NCI-h TERT-CL6.None of the clones exhibited detectable levels of MUC6 nor sialylated Lex and Lea glycans.Entailing good gastric properties,both NCIhT ERT-clones were found to produce pepsinogen-5 and human gastric lipase.The progenitor-like phenotype of NCI-hT ERT-CL6 cells was highlighted by large nuclei and by the apical vesicular-like distribution of mucin 5AC and Pg5,supporting the accumulation of mucus-secreting and zymogens-chief mature cells functions.CONCLUSION:These traits,in addition to resistance to microaerobic conditions and good responsiveness to H.pylori co-culture,in a strain virulence-dependent manner,make the NCI-hT ERT-CL6 a promising model for future in vitro studies.

秦皮乙素对人胃癌SGC-7901细胞增殖、迁移、侵袭和糖酵解的影响

目的探讨秦皮乙素(AES)对胃癌SGC-7901细胞增殖、迁移、侵袭和糖酵解的影响及相关机制。方法采用MTT法检测细胞增殖活性;采用划痕实验和Transwell实验检测细胞迁移和侵袭能力;葡萄糖摄取量测定和乳酸含量测定实验检测细胞糖酵解情况;Western blot法检测迁移、侵袭及糖酵解相关蛋白的表达水平。结果AES能够抑制SGC-7901细胞的增殖活力,且这种抑制效果与AES的剂量成正相关。随着AES剂量的梯度增加,SGC-7901细胞的迁移、侵袭及糖酵解能力逐渐降低(P<0.05)。AES可以下调SGC-7901细胞HIF-1α、MMP-2、MMP-9、GLUT1、LDHA蛋白的表达水平(P<0.05)。结论AES对人胃癌SGC-7901细胞增殖活性及迁移、侵袭能力有抑制作用,通过抑制人胃癌SGC-7901细胞的葡萄糖摄取及乳酸生成降低糖酵解水平。AES可能通过影响缺氧诱导因子HIF-1α抑制SGC-7901细胞迁移、侵袭及有氧糖酵解过程。

胃癌患者EB病毒感染情况及其对癌组织p53、Bcl-2表达的影响

目的探究胃癌患者人类疱疹(EB)病毒感染情况及其对癌组织p53、B淋巴细胞瘤-2(Bcl-2)表达的影响。方法选取新乡市中心医院2019年8月至2023年1月收治的76例胃癌患者,采用原位杂交法检测患者癌组织及癌旁组织EB病毒编码小分子RNA表达,采用逆转录聚合酶链式反应(RT-PCR)法检测患者癌组织及癌旁组织p53、Bcl-2 mRNA表达,分析EB病毒感染与胃癌临床病理特征及癌组织p53、Bcl-2表达的关系。结果76例胃癌患者癌组织标本中EB病毒阳性率为27.63%(21/76),邻近癌旁组织标本中EB病毒阳性率为4.29%(3/76),胃癌患者癌组织EB病毒阳性率高于癌旁组织(P<0.05);与EB病毒阴性的胃癌患者比,EB病毒阳性患者中病灶位于近端胃、组织浸至浆膜层、有淋巴结转移的占比较多(P<0.05);胃癌患者癌组织p53及Bcl-2 mRNA表达均高于癌旁组织(P<0.05);EB病毒感染胃癌患者癌组织p53及Bcl-2 mRNA表达均高于未感染胃癌患者(P<0.05)。结论EB病毒感染与胃癌患者近端胃病变、组织浸至浆膜层及有淋巴结转移有关,EB病毒可能通过驱动宿主p53基因甲基化来上调p53表达,与Bcl-2协同促进癌细胞生长,这些可能为临床提供胃癌诊疗评估因子及免疫治疗新靶点。

阿奇霉素对胃癌细胞增殖、凋亡及炎症因子表达水平的影响

目的探讨阿奇霉素对人胃癌细胞(AGS细胞)上清液中炎症因子表达、增殖和凋亡的影响及核转录因子-κB(NF-κB)信号通路的调控作用。方法体外培养AGS细胞,将其分为对照组(不进行干预)和不同水平(12.5、25.0、50.0、100.0μg/mL)阿奇霉素组,干预24 h,筛选阿奇霉素最适水平用于后续实验。细胞分组:对照组、阿奇霉素组(50.0μg/mL阿奇霉素)、阳性药物组(50.0μg/mL 5-氟尿嘧啶)、抑制剂组(50.0μg/mL阿奇霉素+1.0μmol/L NF-κB通路抑制剂BAY11-7082)和激活剂组(50.0μg/mL阿奇霉素+1.0μmol/L NF-κB通路激动剂Prostratin),干预24 h。采用细胞计数试剂盒-8(CCK-8)检测细胞活力;采用酶联免疫吸附试验(ELISA)测定细胞上清液中的炎症因子[白细胞介素(IL)-10及IL-1β]水平;采用5-乙炔基-2′脱氧尿嘧啶核苷(EdU)测定细胞增殖率;采用Hoechst33258染色试剂盒测定细胞凋亡率;采用蛋白免疫印迹(WB)法测定增殖细胞核抗原(PCNA)、半胱氨酸蛋白酶-3(Caspase-3)及NF-κB通路相关蛋白表达水平。结果用CCK-8检测AGS细胞活力,根据实验结果选择50.0μg/mL阿奇霉素用于后续实验。与对照组比较,阿奇霉素组和阳性药物组AGS细胞上清液中IL-1β水平、细胞增殖率、PCNA表达水平、磷酸化(p)NF-κB p65/NF-κB p65和p-IκBα/IκBα明显降低(P<0.05),IL-10水平、细胞凋亡率和Caspase-3表达水平明显升高(P<0.05);与阿奇霉素组比较,抑制剂组中BAY11-7082的出现增强了阿奇霉素对AGS细胞的作用(P<0.05),激活剂组中Prostratin的出现则削弱了阿奇霉素对AGS细胞的作用(P<0.05)。结论阿奇霉素能抑制AGS细胞的炎症和增殖,并诱导其凋亡,其作用机制可能与阻滞NF-κB通路信号转导有关。

槟榔碱对人胃黏膜上皮细胞的毒性作用研究

本文旨在探讨槟榔碱对人胃黏膜上皮细胞GES-1的毒性作用。用不同浓度(60、90、120、150μg/mL)的槟榔碱处理GES-1细胞,并检测GES-1细胞活力、活性氧水平(Reactive Oxygen Species,ROS)和线粒体膜电位(Mitochondrial Membrane Potential,MMP),测定GES-1细胞还原型谷胱甘肽(Glutathione,GSH)水平、超氧化物歧化酶(Superoxide Dismutase,SOD)活力、乳酸脱氢酶(Lactate dehydrogenase,LDH)活力、三磷酸腺苷(ATP)酶活力。测定肿瘤坏死因子-α(Tumor Necrosis Factor-α,TNF-α)、白介素-6(Interleukin 6,IL-6)、血管内皮生长因子(Vascular Endothelial Growth Factor,VEGF)、转化生长因子-β(Transforming Growth Factor-β,TGF-β)水平。结果表明,与空白对照组相比,槟榔碱刺激后GES-1细胞形态发生改变,细胞活力最低降低至24%,活性氧水平最高升至12.5倍,线粒体膜电位最低下降至10.4%。在150μg/mL槟榔碱刺激下,总ATP酶以及Na^(+)K^(+)-ATP酶活力分别下降至42.31%和39.84%,GSH和SOD分别下降了40.23%和34.1%,LDH上升了30.46%,TNF-α、IL-6、VEGF、TGF-β水平分别上升了4.67%、10.2%、23.14%和22.83%。结果表明槟榔碱能够产生氧化应激并诱发炎症因子,对GES-1细胞造成毒性损伤。