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Following the publication of this article, an interested reader drew to the authors' attention that two images in Fig. 1B (the a and d panels) appeared to represent the same clone, albeit with different intensities and the panels were cropped differently. The authors were able to confirm that Figs. 1B(a) and B(d) were inadvertently selected from the same set of images but with different exposure times: Owing to an error in data handling, a wrong image was chosen during the grouping the figures. The corrected version of Fig. 1 is shown on the next page, featuring the correct image for Fig. 1B(d). The authors regret that this error was not picked up upon before the paper was sent to press, although the error did not affect the major conclusions reported in the paper. The authors thank the Editor of International Journal of Oncology for allowing them the opportunity to publish a Corrigendum. and regret any inconvenience caused to the readership. [the origional article was published on International Journal of Oncology 40: 16011609, 2012; DOI: 10.3892/ijo.2012.1338].
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N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) is an alkylating agent that can induce gastric carcinoma. As a well-known human carcinogen, MNNG has been universally recognized as a methylating agent and is believed to act through methylation mechanism. In the present study, the epigenetic status of the human telomerase reverse transcriptase (hTERT) promoter was investigated in MNNG-treated normal human gastric mucosal epithelial cells. After 4 h exposure to MNNG at different concentrations, 6.8 and 68 µM, bisulfite sequencing polymerase chain reaction showed that five methylated cytosines outside the CpG dinucleotides in the 290-bp fragment from the hTERT promoter were demethylated and all the methylated cytosines in CpG dinucleotides remained intact. Furthermore, the epigenetic status of the target region following MNNG exposure was extremely similar to those of the BGC-823, SGC-7901 and MKN-28 lines; the three cell lines from human gastric adenocarcinoma. The result indicates that MNNG-induced demethylation in cytosines outside the CpG dinucleotides may be an early molecular lesion with the potential for impacting malignant transformation and a possible underlying carcinogenic mechanism of MNNG. Thus, it may provide another insight into the mechanisms of MNNG carcinogenesis.
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AIM: To determine the prevalence, demographic, clinical and histopathologic features of heterotopic gastric mucosa (HGM) in Chinese patients. METHODS: Patients referred to three endoscopy units were enrolled in this study. The macroscopic characteristics of HGM were documented. Biopsies were obtained and observed using hematoxylin and eosin staining. Helicobacter pylori colonization was examined by Whartin-Starry staining. RESULTS: HGM was observed in 420 Chinese patients, yielding a prevalence of 0.4%. The majority of patients had a single patch (300/420; 71.4%), while the remainder had two (84/420; 20%) or multiple patches (36/420; 8.6%). The size of the patches and the distance from the patch to the frontal incisor teeth varied significantly. The large majority of HGM patches were flat (393/420; 93.6%), whereas the remaining patches were slightly elevated. The primary histological characteristic was fundic-type (216/420; 51.4%) within the HGM patch, and antral- (43/420; 10.2%) and transitional-type (65/420; 15.5%) mucosa were also observed. The prevalence of intestinal metaplasia was 3.1% (13/420) and the prevalence of dysplasia was 1.4% (6/420), indicating the necessity for endoscopic follow-up in patients with HGM. Esophageal and extraesophageal complaints were also observed in patients with HGM. Dysphagia and epigastric discomfort (odds ratios: 6.836 and 115.826, respectively; Ps < 0.05) were independent risk factors for HGM. CONCLUSION: Clinical complaints should be considered to improve the detection rate of HMG. The prevalence of intestinal metaplasia and dysplasia also indicates a need for endoscopic follow-up.
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Povo Asiático , Coristoma/etnologia , Doenças do Esôfago/etnologia , Mucosa Gástrica , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia , Distribuição de Qui-Quadrado , China/epidemiologia , Coristoma/microbiologia , Coristoma/patologia , Doenças do Esôfago/microbiologia , Doenças do Esôfago/patologia , Esofagoscopia , Feminino , Infecções por Helicobacter/etnologia , Infecções por Helicobacter/microbiologia , Helicobacter pylori/isolamento & purificação , Humanos , Modelos Logísticos , Masculino , Metaplasia , Pessoa de Meia-Idade , Análise Multivariada , Razão de Chances , Prevalência , Estudos Prospectivos , Fatores de Risco , Adulto JovemRESUMO
BACKGROUND/AIMS: To investigate the differential expression of RING finger (RNF) proteins in Barrett esophagus (BE) and esophageal adenocarcinoma (EAC). METHODS: The differential expression of RNFs in normal esophagus (NE), BE, and EAC was screened using microarray assay. Real-time quantitative polymerase chain reaction (PCR), tissue micro-array assay, and Western blot analysis were independently performed to detect the mRNA and protein expression of screened RNFs. RESULTS: The expression of nine RNFs in the BE or EAC was 2-fold higher than those in NE. Among these proteins, the RNF32 and RNF121 expression in BE was 20.3-fold and 16.4-fold higher, respectively, than that in NE, and the expression of RNF24, RNF130, RNF141, RNF139, RNF11, RNF14, and RNF159 was upregulated more than 2-fold compared with NE. The expression of nine RNFs was not only upregulated in the EAC but was also positively related to the RNF expression in BE. The PCR results also indicated increased expression of these RNFs in BE and EAC compared to NE. Furthermore, the mRNA expression of all RNFs, except for RNF141 in EAC, was dramatically higher than those in the BE. Similar results were also obtained from the Western blot analysis. CONCLUSIONS: A total of nine RNFs play critical roles in the progression of BE to EAC.
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Adenocarcinoma/enzimologia , Esôfago de Barrett/enzimologia , Neoplasias Esofágicas/enzimologia , Domínios RING Finger , Ubiquitina-Proteína Ligases/metabolismo , Adenocarcinoma/genética , Adulto , Idoso , Esôfago de Barrett/genética , Proteínas de Transporte/genética , Proteínas de Ligação a DNA , Progressão da Doença , Neoplasias Esofágicas/genética , Feminino , Perfilação da Expressão Gênica , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Masculino , Pessoa de Meia-Idade , Proteínas/genética , Receptores de Superfície Celular/genética , Ubiquitina-Proteína Ligases/genéticaRESUMO
AIM: To investigate telomerase activity and human telomerase reverse transcriptase (hTERT) expression in normal human gastric mucosal epithelial cells (nhGMECs) and fibroblasts (nhGMFs). METHODS: nhGMECs and nhGMFs were isolated and cultured from specimens obtained during routine surgery for bleeding peptic ulcer. Telomerase activity in nhGMFs, nhGMECs, and the tumor cell lines BGC-823, SGC-7901 and MKN-28 cells was analyzed using the telomeric repeat amplification protocol assay. hTERT protein was determined in nhGMECs, nhGMFs, BGC-823, SGC-7901 and MKN-28 cells by indirect immunofluorescence. RESULTS: A similar level of telomerase activity was observed in nhGMECs, nhGMFs and BGC-823, SGC-7901, MKN-28 cell lines. Positive hTERT immunostaining was detected in nhGMECs, nhGMFs, BGC-823, SGC-7901 and MKN-28 cell lines. CONCLUSION: The use of telomerase or hTERT as diagnostic markers for gastric cancer may require further studies.
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Biomarcadores Tumorais/metabolismo , Fibroblastos/metabolismo , Mucosa Gástrica/patologia , Neoplasias Gástricas/enzimologia , Neoplasias Gástricas/genética , Telomerase/metabolismo , Adulto , Idoso , Linhagem Celular Tumoral , Sobrevivência Celular , Células Cultivadas , Feminino , Marcadores Genéticos , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
Previous studies have indicated that heparanase (Hpa) might represent a candidate universal tumor-associated antigen. However, vaccine therapy targeting only one cytotoxic T lymphocyte (CTL) epitope is suboptimal in preventing cancer. In the present study, we designed heparanase multi-epitope vaccines to increase the immune response to standard single heparanase epitopes. The results showed that multi-epitope vaccines Hpa525 + 277 + 405 + 16 and Hpa8 + 310 + 315 + 363 induced higher Hpa-specific lysis of various cancer cells from different tissues in a HLA-A2-restricted and heparanase-specific manner compared with the single epitope vaccines Hpa525, Hpa277, Hpa405, Hpa16, Hpa8, Hpa310, Hpa315 and Hpa363, both in vitro and ex vivo. Heparanase multi-epitope vaccines not only induced the heparanase-specific CTL to lyse tumor cells but also increased CTL secretion of interferon-γ. However, these heparanase-specific CTL did not lyse heparanase-expressing autologous lymphocytes and dendritic cells, which confirms the safety of these multi-epitope vaccines. Therefore, the present study provides theoretical evidence for the use of heparanase multi-epitope vaccines for clinical application.
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Vacinas Anticâncer/imunologia , Epitopos de Linfócito T/imunologia , Heparina Liase/imunologia , Animais , Antígenos de Neoplasias/imunologia , Linhagem Celular Tumoral , Epitopos/imunologia , Antígeno HLA-A2/imunologia , Células Hep G2 , Humanos , Interferon gama/imunologia , Células MCF-7 , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Linfócitos T Citotóxicos/imunologiaRESUMO
BACKGROUND: Colorectal cancer (CRC) is steadily increasing in China. Colorectal adenoma (CRA) is the most important precancerous disease of CRC. Screening for colorectal tumors can aid early diagnosis. Advances in endoscopic mucosal resection and endoscopic submucosal dissection can aid the early treatment of colorectal tumors. Furthermore, because of high risk of recurrence after removal of adenomas under endoscopy, factors contributing to recurrence, the follow-up mode and the interval established, and the feasibility of application and the time of various chemical preventions should be concerned. However, a relevant consensus on the screening, early diagnosis and treatment, and prevention of colorectal tumors in China is lacking. SUMMARY: The consensus recommendations include epidemiology, pathology, screening, early diagnosis, endoscopic treatment, monitoring and follow-up, and chemoprevention of colorectal tumors in China. KEY MESSAGE: This is the first consensus on the prevention, screening, early diagnosis and treatment of CRA and CRC in China based on evidence in the literature and on local data. PRACTICAL IMPLICATIONS: Through reviewing the literature, regional data and passing the consensus by an anonymous vote, gastroenterology experts from all over China launch the consensus recommendations in Shanghai. The incidence and mortality of CRC in China has increased, and the incidence or detection rate of CRA has increased rapidly. Screening for colorectal tumors should be performed at age 50-74 years. Preliminary screening should be undertaken to find persons at high risk, followed by colonoscopy. A screening cycle of 3 years is recommended for persistent interventions. Opportunistic screening is a mode suitable for the current healthcare system and national situation. Colonoscopy combined with pathological examination is the standard method for the diagnosis of colorectal tumors. CRA removal under endoscopy can prevent CRC to some extent, but CRA has an obvious recurrence trend. The follow-up interval after the removal or surgery of colorectal tumors should be different with lesions. Primary prevention of CRA includes improved diet with more fiber, supplements containing calcium and vitamin D, supplements containing folic acid for those with low hemoglobin levels, and cessation of tobacco smoking. Non-steroidal anti-inflammatory drugs and selective cyclooxygenase-2 inhibitors have been recognized to prevent recurrence after adenoma removal.
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Induction of murine double minute 2 (MDM2) expression is thought to be a determinant of resistance to p53 gene therapy for cancer. Previous studies have revealed that ribosomal protein L23 (RPL23) inhibits MDM2-mediated p53 degradation through direct binding to MDM2. In addition, ectopically expressed RPL23 was reported to interact with MDM2 in both the nucleus and cytoplasm, by which RPL23 indirectly inhibited MDM2-p53 binding. Based on the known molecular properties of the RPL23 protein, it was speculated that co-transduction of RPL23 may protect wildtype p53 protein from MDM2-mediated inactivation and, thus, improve the effect of delivering therapeutic exogenous p53. To test this hypothesis, we constructed a bicistronic adenoviral vector expressing both the RPL23 and p53 genes (Ad-RPL23/p53) and compared its tumor-suppressor activity in human gastric cancer with that of a single gene vector for p53 (Ad-p53). In the in vivo and in vitro experiments, we observed that treatment with Ad-RPL23/p53 resulted in a stronger antitumor response compared to that obtained using Ad-p53. Moreover, the antitumor response of the bicistronic adenovirus was obtained not only in MGC803 cells (endogenous mutant p53) but also in MKN45 cells (endogenous wildtype p53) which were initially resistant to p53 gene transfer, indicating that co-transduction of RPL23 also expanded the utility of p53 gene therapy. Furthermore, in an orthotopic nude mouse model of human gastric cancer, we found that the survival benefit was greater after Ad-RPL23/p53 treatment than after Ad-p53. Taken together, the data presented here demonstrate that co-transduction of RPL23 enhances the therapeutic efficacy of adenoviral-mediated p53 gene transfer in models of human gastric cancer and support the use of this strategy for cancer treatment.
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Apoptose/genética , Proteínas Mitocondriais/genética , Proteínas Ribossômicas/genética , Neoplasias Gástricas/terapia , Proteína Supressora de Tumor p53/genética , Adenoviridae/genética , Animais , Proteínas Reguladoras de Apoptose/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Sobrevivência Celular/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Terapia Genética/métodos , Vetores Genéticos , Xenoenxertos , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Transplante de Neoplasias , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-mdm2/genética , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Proteínas de Ligação a RNA , Neoplasias Gástricas/genética , Transdução GenéticaRESUMO
Colorectal adenoma (CRA) is the precursor lesion of colorectal cancer (CRC). Several agents have been shown to be effective in the chemoprevention of CRA recurrence, but there has been little research on its primary prevention. Participants older than 50 years with no adenomas were recruited for our study and randomized to receive either 1 mg/day folic acid supplement or treatment without folic acid. After 3 years of follow-up, plasma folate and colonoscopy were evaluated. Seven hundred ninety-one participants (91.98%) completed the study. CRA occurred in 64 (14.88%) participants in the folic acid group and 132 (30.70%) in the control group [unadjusted risk ratio (RR), 0.49; 95% confidence interval (CI), 0.37-0.63; P < 0.01]; left-sided adenoma (unadjusted RR, 0.54; 95% CI, 0.38-0.76; P = 0.001) and advanced CRA (unadjusted RR, 0.36; 95% CI, 0.16-0.81; P = 0.01) were most common. There was no significance difference in the occurrence of three or more adenomas (unadjusted RR, 0.70; 95% CI, 0.36-1.77; P = 0.38) or right-sided adenoma (unadjusted RR, 0.55; 95% CI, 0.30-1.00; P = 0.07) between the two groups. Participants with low plasma folate may have a high risk of CRA. In conclusion, primary prevention with 1 mg/day folic acid supplementation could reduce the incidence of CRA, especially left-sided and advanced disease in those with no previous adenomas. People with differing baseline plasma folate levels should be given individualized treatment. Those with low plasma folate should be encouraged to take adequate supplements; plasma folate should be elevated to an effective therapeutic level, which may reduce the incidence of CRA.
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Adenoma/prevenção & controle , Neoplasias Colorretais/prevenção & controle , Suplementos Nutricionais , Ácido Fólico/uso terapêutico , Recidiva Local de Neoplasia/prevenção & controle , Complexo Vitamínico B/uso terapêutico , Adenoma/epidemiologia , Adenoma/etiologia , Estudos de Casos e Controles , Colonoscopia , Neoplasias Colorretais/epidemiologia , Neoplasias Colorretais/etiologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/epidemiologia , Prognóstico , Estudos Prospectivos , Fatores de RiscoRESUMO
BACKGROUND: Accumulating evidence indicates that diet is one of the most important environmental factors involved in the progression from advanced colorectal adenoma (A-CRA) to colorectal cancer. OBJECTIVE: We evaluated the possible effects of dietary fiber on the fecal microbiota of patients with A-CRA. DESIGN: Patients with a diagnosis of A-CRA by pathological examination were enrolled in the A-CRA group. Patients with no obvious abnormalities or histopathological changes were enrolled in the healthy control (HC) group. Dietary fiber intake was assessed in all patients. Short-chain fatty acids (SCFAs) in feces were detected by gas chromatography. The fecal microbiota community was analyzed by 454 pyrosequencing based on 16S ribosomal RNA. RESULTS: Lower dietary fiber patterns and consistently lower SCFA production were observed in the A-CRA group (n = 344). Principal component analysis showed distinct differences in the fecal microbiota communities of the 2 groups. Clostridium, Roseburia, and Eubacterium spp. were significantly less prevalent in the A-CRA group (n = 47) than in the HC group (n = 47), whereas Enterococcus and Streptococcus spp. were more prevalent in the A-CRA group (n = 47) (all P < 0.05). Butyrate and butyrate-producing bacteria were more prevalent in a subgroup of HC subjects with a high fiber intake than in those in both the low-fiber HC subgroup and the high-fiber A-CRA subgroup (all P < 0.05). CONCLUSION: A high-fiber dietary pattern and subsequent consistent production of SCFAs and healthy gut microbiota are associated with a reduced risk of A-CRA. This trial was registered at www.chictr.org as ChiCTR-TRC-00000123.
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Neoplasias Colorretais/epidemiologia , Fibras na Dieta/administração & dosagem , Trato Gastrointestinal/microbiologia , Metagenoma , Idoso , Butiratos/metabolismo , Estudos de Casos e Controles , China/epidemiologia , Cromatografia Gasosa , Neoplasias Colorretais/microbiologia , Neoplasias Colorretais/fisiopatologia , Estudos Transversais , DNA Bacteriano/genética , Dieta , Ácidos Graxos Voláteis/análise , Fezes/química , Fezes/microbiologia , Feminino , Bactérias Gram-Positivas/genética , Bactérias Gram-Positivas/isolamento & purificação , Humanos , Estilo de Vida , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Inquéritos e QuestionáriosRESUMO
Resistance to anoikis, the subtype of apoptosis induced by lack of matrix adhesion, contributes to malignant transformation and development of metastasis. MicroRNAs play key regulatory roles in tumorigenesis and metastasis. In this study, we described that miR-26a, which is usually downregulated in tumor cells, is involved in the acquisition of anoikis-resistance of human esophageal adenocarcinoma (EA) cells. Results of qRT-PCR in clinical samples showed that downregulated miR-26a expression is related to tumorigenesis and metastasis of EA. In vitro experiments determined that miR-26a directly participates in the regulation of cell cycle and anoikis of human EA OE33 cells. Further, we identified that Rb1 is the direct functional target of miR-26a, and revealed that the reduction of miR-26a expression leads to increased Rb1 protein level and thus inhibits the function of E2F1, by which it influences the phenotypes of cell cycle and anoikis. The findings we reported here presented the evidence that miR-26a may be involved in regulation of anoikis-resistance of EA cells. Targeting miR-26a may provide a novel strategy to inhibit metastasis.
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Adenocarcinoma/metabolismo , Anoikis , Fator de Transcrição E2F1/metabolismo , Neoplasias Esofágicas/metabolismo , MicroRNAs/fisiologia , Proteína do Retinoblastoma/genética , Regiões 3' não Traduzidas , Adenocarcinoma/secundário , Animais , Sequência de Bases , Sítios de Ligação , Pontos de Checagem do Ciclo Celular , Linhagem Celular Tumoral , Sobrevivência Celular , Regulação para Baixo , Neoplasias Esofágicas/patologia , Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Metástase Linfática , Camundongos , Camundongos Nus , Transplante de Neoplasias , Interferência de RNA , Proteína do Retinoblastoma/metabolismo , Transdução de Sinais , Transcrição GênicaRESUMO
Human telomerase reverse transcriptase (hTERT) has been identiï¬ed as a major protein involved in aberrant cell proliferation, immortalization, metastasis and stemness maintenance in a majority of tumors, yet it has little or no expression in normal somatic cells. During the past few years, the development of hTERT-based therapies such as immunotherapy, suicide gene therapy and small-molecule interfering therapy have become critical and specific for eradicating all types of cancer. Here, current knowledge regarding hTERT and its involvement in various cancers and its role as a target of cancer therapies are reviewed. Additionally, hurdles to new cancer therapy development and new therapeutic opportunities are described, along with areas that require further investigation.
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Neoplasias/tratamento farmacológico , Telomerase , Apoptose , Proliferação de Células , Terapia Genética , Humanos , Imunoterapia , Neoplasias/patologia , Telomerase/antagonistas & inibidores , Telomerase/biossíntese , Telomerase/genéticaRESUMO
Activation of telomerase is involved in carcinogenesis in most types of cancers. However, the prognostic value of telomerase activity (TA) in patients with gastric carcinoma (GC) remains controversial. We conducted a meta-analysis to assess the relationship between TA and the clinical outcome of GC. A meta-analysis of 18 studies (886 patients) was performed to evaluate the association between TA and metastasis-related parameters in GC patients by searching databases, including PubMed, MEDLINE, EMBASE, Web of Science databases, Cochrane Library and the Chinese Biomedical Literature database (CBM) (last search updated in October 2011). We used the odds ratios (ORs) with 95% confidence intervals (CIs) to assess the strength of the association between TA and metastasis of GC. Our analysis results indicated that high telomerase activity expression tended to be associated with the presence of lymph node metastasis (866 patients) (OR=2.03, 95% CI 1.21-3.39, p=0.007), the depth of invasion (886 patients) (OR=1.87, 95% CI 1.30-2.70, p=0.0007), distant metastasis (407 patients) (OR=2.71, 95% CI 1.59-4.63, p=0.0002), tumor size (466 patients) (OR=2.14, 95% CI 1.31-3.50, p=0.002) and TNM stage (711 patients) (OR=2.39, 95% CI 1.30-4.41, p=0.005). However, high TA expression was not associated with the presence of histologic differentiation (791 patients) (OR=1.51, 95% CI 0.73-3.11, p=0.26). In conclusion, telomerase overexpression not only plays a key role in primary initiation, but also promotes invasion and metastatic progression of GC. These findings raise the possibility of using TA to screen for the prognosis of gastric cancer.
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The development of peptide vaccines aimed at enhancing immune responses against tumor cells is becoming a promising area of research. Human telomerase reverse transcriptase (hTERT) is an ideal universal target for novel immunotherapies against cancers. The aim of this work was to verify whether the multiple antigen peptides (MAP) based on HLA-A0201-restricted CTL epitopes of hTERT could trigger a better and more sustained CTL response and kill multiple types of hTERT-positive tumor cells in vitro and ex vivo. Dendritic cells (DC) pulsed with MAP based on HLA-A0201-restricted CTL epitopes of hTERT (hTERT-540, hTERT-865 and hTERT-572Y) were used to evaluate immune responses against various tumors and were compared to the immune responses resulting from the use of corresponding linear epitopes and a recombinant adenovirus-hTERT vector. A 4-h standard (51) Cr-release assay and an ELISPOT assay were used for both in vitro and ex vivo analyses. Results demonstrated that targeting hTERT with an adenovector was the most effective way to stimulate a CD8(+) T cell response. When compared with linear hTERT epitopes, MAP could trigger stronger hTERT-specific CTL responses against tumor cells expressing hTERT and HLA-A0201. In contrast, the activated CTL could neither kill the hTERT-negative tumor cells, such as U2OS cells, nor kill HLA-A0201 negative cells, such as HepG2 cells. We also found that these peptide-specific CTL could not kill autologous lymphocytes and DC with low telomerase activity. Our results indicate that MAP from hTERT can be exploited for cancer immunotherapy.
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Antineoplásicos/farmacologia , Epitopos de Linfócito T/imunologia , Antígeno HLA-A2/imunologia , Neoplasias/terapia , Peptídeos/imunologia , Linfócitos T Citotóxicos/imunologia , Telomerase/imunologia , Animais , Antineoplásicos/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Vacinas Anticâncer/imunologia , Vacinas Anticâncer/farmacologia , Linhagem Celular Tumoral , Células Dendríticas/imunologia , Vetores Genéticos/imunologia , Células Hep G2 , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Neoplasias/imunologia , Peptídeos/farmacologia , Vacinas de Subunidades Antigênicas/imunologiaRESUMO
In this study, we present a case of a 43-year-old female patient who was admitted to our hospital due to a giant mass on the left buttock. Imaging tests revealed that the mass was a solid-cystic tumor with a large size of 143×430×180 mm, penetrating from the pelvic cavity to the subcutaneous tissue. Pathology tests indicated a metastatic mucinous adenocarcinoma which was most likely of gastrointestinal origin. However, there was no evidence to confirm the existence of malignant changes in the gastrointestinal tract.
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Accumulating research suggests that heparanase may be a universal tumor-associated antigen (TAA). Several heparanase T-cell epitopes from humans and mice have already been identified. However, because of low immunogenicity, polypeptide vaccines usually have difficulty inducing effective antitumor immune responses in vivo. In this study, to increase the immunogenicity of polypeptide vaccines, we designed and synthesized two four-branch multiple antigenic peptides (MAP) on the basis of mouse heparanase (mHpa) T-cell epitopes (mHpa398 and mHpa519). The dendritic cells (DC) from mice bone marrow loaded with above MAP vaccines from heparanase were used to evaluate immune response against various tumor cell lines, compared with immune response to their corresponding linear peptides, ex vivo and in vivo. We further assessed IFN-γ release both in CD4(+) T-cell-depleted and nondepleted mice. The results showed that effectors generated from DCs, loaded with MAP-vaccinated mice splenocytes, induced a stronger immune response against target cells expressing both heparanase and H-2K(b) than did effectors generated from mice vaccinated with their corresponding linear peptides. Heparanase-specific CD8(+) T-cell responses induced by MAP and linear peptide vaccination required synergy of CD4(+) T cells. In addition, heparanse-derived MAP vaccines significantly inhibited the growth of B16 murine melanoma in C57BL/6 mice, while also increasing the survival rate of tumor-bearing mice. Our data suggest that MAP vaccines based on T-cell epitopes from heparanase are efficient immunogens for tumor immunotherapy.
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Epitopos de Linfócito T/imunologia , Glucuronidase/imunologia , Antígenos H-2/imunologia , Neoplasias/imunologia , Peptídeos/imunologia , Linfócitos T Citotóxicos/imunologia , Sequência de Aminoácidos , Animais , Vacinas Anticâncer/imunologia , Linhagem Celular Tumoral , Citotoxicidade Imunológica/imunologia , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Epitopos de Linfócito T/química , Epitopos de Linfócito T/isolamento & purificação , Glucuronidase/química , Glucuronidase/isolamento & purificação , Humanos , Imunofenotipagem , Imunoterapia , Interferon gama/biossíntese , Camundongos , Camundongos Endogâmicos C57BL , Neoplasias/mortalidade , Neoplasias/terapia , Peptídeos/química , Peptídeos/isolamento & purificaçãoRESUMO
In order to prevent the development of Barrett's esophagus (BE)-related esophageal cancer in China and facilitate the communication of research results among different centers, we propose using standardized diagnostic criteria and taking a conservative approach to diagnose and manage BE patients. BE patients without dysplasia need to be treated medically. For low-grade dysplasia, an annual endoscopy with biopsies is recommended, along with medical therapy. For high-grade dysplasia and intramucosal carcinoma, an endoscopic or surgical intervention is suggested. All BE patients should be followed up closely.
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Adenocarcinoma/patologia , Esôfago de Barrett/patologia , Esôfago de Barrett/terapia , Transformação Celular Neoplásica , Neoplasias Esofágicas/patologia , Adenocarcinoma/cirurgia , Esôfago de Barrett/etiologia , Biópsia , China , Neoplasias Esofágicas/cirurgia , Esofagoscopia , Refluxo Gastroesofágico/complicações , Refluxo Gastroesofágico/tratamento farmacológico , HumanosRESUMO
Heparanase is an endoglycosidase that degrades heparan sulfate, the main polysaccharide constituent of the extracellular matrix and basement membrane. The expression of heparanase is associated with invasion, as well as the angiogenic and metastatic potential of diverse malignant tumors. We used RNA interference strategies to evaluate the role of human heparanase in a liver cancer cell line and to explore the therapeutic potential of its specific targeting. Using an online siRNA tool, we designed three small interfering RNA sequences to target the heparanase coding region and cloned them into the pGenesil-1 vector. The siRNA vectors were transfected into HepG2 liver cancer cells. Heparanase expression was measured by real-time RT-PCR and Western blotting. Cell proliferation was detected by MTT staining and plate colony formation. Cell cycle analysis was performed by flow cytometry. In vitro invasion was measured by Matrigel invasion assay. We also analyzed tumorigenicity in heparanase-suppressed HepG2 cells in nude mice. We found that siRNA-1 (1214-1232) and siRNA-3 (611-629) targeting heparanase significantly downregulated the expression of heparanase in HepG2 liver cancer cells. Compared with its controls, siRNA-1 or siRNA-3 vectors efficiently inhibi-ted the proliferation and invasion of HepG2 liver cancer cells in vitro and tumorigenesis in vivo. These results suggest that heparanase-specific RNA interference has potential value as a novel therapeutic agent for human liver cancer.
Assuntos
Carcinoma Hepatocelular/terapia , Proliferação de Células , Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Terapia Genética/métodos , Glucuronidase/metabolismo , Neoplasias Hepáticas/terapia , Interferência de RNA , Animais , Sequência de Bases , Western Blotting , Carcinoma Hepatocelular/enzimologia , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Ciclo Celular , Regulação para Baixo , Citometria de Fluxo , Glucuronidase/genética , Células Hep G2 , Humanos , Neoplasias Hepáticas/enzimologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Masculino , Camundongos , Camundongos Nus , Dados de Sequência Molecular , Células NIH 3T3 , Invasividade Neoplásica , Reação em Cadeia da Polimerase em Tempo Real , Fatores de Tempo , Transdução Genética , Transfecção , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
BACKGROUND: Telomerase is commonly recognized as an effective anticancer target. The human telomerase reverse transcriptase (hTERT), the rate-limiting component of telomerase, is expressed in most malignant tumors, but it is not found in most normal somatic cells. Here, we report a real-time and noninvasive method to monitor tumor response to a lentivirus-based hTERT-conditional suicidal gene therapy. METHODS: In this study, we constructed a lentivirus system in which an optimized hTERT promoter was used to drive the expression of the cytosine deaminase (CD) gene, one of the suicide genes, and a green fluorescent protein (GFP) reporter gene (pLenti-CD/GFP). The lentivirus was used to infect telomerase-positive or telomerase-negative cell lines. In vitro and in vivo experiments were conducted to analyze the dynamic processes of exogenous gene expression noninvasively in cell culture and living animals in real time via optical imaging. RESULTS: The lentivirus was able to express the CD gene and GFP in telomerase-positive tumor cells and significantly decrease cell proliferation after the use of prodrug 5-flucytosine. However, it could not express GFP and CD in telomerase-negative cell lines, nor could it induce any suicidal effect in those cells. The in vivo study showed that telomerase-positive tumors can be visualized after intratumor injection of the lentivirus in tumor-bearing nude mice via an optical imaging system. Significant tumor growth suppression was observed in telomerase-positive tumors. CONCLUSIONS: Collectively, this technology provides a valuable, noninvasive method to evaluate the real-time therapeutic response of tumors in vivo.
Assuntos
Sistemas Computacionais , Citosina Desaminase/metabolismo , Monitoramento de Medicamentos/métodos , Terapia Genética/métodos , Neoplasias/terapia , Telomerase/genética , Animais , Linhagem Celular Tumoral , Citosina Desaminase/genética , Flucitosina , Genes Reporter , Genes Transgênicos Suicidas , Proteínas de Fluorescência Verde/genética , Humanos , Lentivirus/genética , Camundongos , Camundongos Nus , Neoplasias/genética , Regiões Promotoras Genéticas , Resultado do Tratamento , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
To standardize the diagnosis and management of Barrett's esophagus (BE) in China, the Chinese Society of Gastroenterology convened the Second National Conference on BE in June 2011 in Chongqing, China. After intense discussion among experts in this field and an extensive review of the literature, a revised consensus on the diagnosis and management of BE was generated.