The abnormality of the p53 tumor suppressor is crucial in lung cancer development,because p53 regulates target gene promoters to combat cancer.Recent studies have shown extensive p53 binding to enhancer elements.Howev...The abnormality of the p53 tumor suppressor is crucial in lung cancer development,because p53 regulates target gene promoters to combat cancer.Recent studies have shown extensive p53 binding to enhancer elements.However,whether p53 exerts a tumor suppressor role by shaping the enhancer landscape remains poorly understood.In the current study,we employed several functional genomics approaches to assess the enhancer activity at p53 binding sites throughout the genome based on our established TP53 knockout(KO)human bronchial epithelial cells(BEAS-2B).A total of 943 active regular enhancers and 370 super-enhancers(SEs)disappeared upon the deletion of p53,indicating that p53 modulates the activity of hundreds of enhancer elements.We found that one p53-dependent SE,located on chromosome 9 and designated as KLF4-SE,regulated the expression of the Krüppel-like factor 4(KLF4)gene.Furthermore,the deletion of p53 significantly decreased the KLF4-SE enhancer activity and the KLF4 expression,but increased colony formation ability in the nitrosamines 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone-induced cell transformation model.Subsequently,in TP53 KO cells,the overexpression of KLF4 partially reversed the increased clonogenic capacity caused by p53 deficiency.Consistently,KLF4 expression also decreased in lung cancer tissues and cell lines.It appeared that overexpression of KLF4 significantly suppressed the proliferation and migration of lung cancer cells.Collectively,our results suggest that the regulation of enhancer formation and activity by p53 is an integral component of the p53 tumor suppressor function.Therefore,our findings offer some novel insights into the regulation mechanism of p53 in lung oncogenesis and introduce a new strategy for screening therapeutic targets.展开更多
AIM: Overexpression of tumor protein p53-induced nudear protein 1 (TP53INP1) induces G1 cell cycle arrest and increases p53-mediated apoptosis. To clarify the clinical importance of TP53INP1, we analyzed TP53INP1 a...AIM: Overexpression of tumor protein p53-induced nudear protein 1 (TP53INP1) induces G1 cell cycle arrest and increases p53-mediated apoptosis. To clarify the clinical importance of TP53INP1, we analyzed TP53INP1 and p53 expression in gastric cancer, METHODS: TP53INP1 and p53 expression were examined using immunohistochemistry in 142 cases of gastric cancer. The apoptosis of gastric cancer cells was analyzed using the TUNEL method. The relationship between the expression of TP53INP1 and clinicopathological factors was statistically analyzed. RESULTS: TP53INP1 was expressed in 98% (139/142 cases) of non-cancerous gastric tissues and was downexpressed in 64% (91/142 cases) of gastric cancer lesions from the same patients. TP53INP1 expression was significantly decreased (43.9%) in poorly differentiated adenocarcinoma compared with well or moderately differentiated adenocarcinoma (81.6%). Cancers invading the submucosa or deeper showed lower positively (59.1%) compared with mucosal cancers (85.2%). Decrease or loss of TP53INP1 expression was significantly correlated with lymphatic invasion (54.3% vs 82.0% without lymphatic invasion) and node-positive patients (31.3% vs 68.3% in node-negative patients). P53 was expressed in 68 (47.9%) patients of gastric cancer, whereas it was absent in normal gastric tissues. A significant association was also observed between TP53INP1 status and the level of apoptosis in tumor cells: the apoptotic index in TP53INP1-positive tissues was significantly higher than that in TP53INP41-negative portions. Finally, when survival data were analyzed, loss of TP53INP1 expression had a significant effect in predicting a poor prognosis (P= 0.0006).CONCLUSION: TPS3INP1-positive rate decreases with the progression of gastric cancer. TPS3INP1 protein negativity is significantly associated with aggressive pathological phenotypes of gastric cancer. TPS3INP1 is related to the apoptosis of gastric cancer cells. The decreased expression of the TPS3INP1 protein may reflect the malignant grade of gastric cancer and is regarded as an adverse prognostic factor.展开更多
AIMS To examine the prevalance of p53 mutations in hepatocellular carcinoma (HCC) from Chongqing area and the relationship between the p53 mutations and clinicopathological features of HCC,as well as the risk factors....AIMS To examine the prevalance of p53 mutations in hepatocellular carcinoma (HCC) from Chongqing area and the relationship between the p53 mutations and clinicopathological features of HCC,as well as the risk factors. METHODS The overexpression and point mutations of tumor suppressor gene p53 in 38 cases of HCC were detected by a sensitive antigen retrieval fluid (ARF) immunohistochemical method and polymerase chain re- action(PCR)-restriction fragment length polymorphism (RFLP),and single strand conformation polymorphism (SSCP)-silver staining analysis. RESULTS The results showed that 16 of 38 HCCs had positive p53 protein (42.1%),7 HCCs had p53 mutation at 249 (18.4 % ) and 2 HCCS had point muta- tion within exon 7 other than 249. Among 9 cases of HCC with mutations,8 cases demonstrated positive p53 protein,its coincidental rate was 88.9%. The overexpression and mutations of p53 were significantly related to the differentiation and metastasis of HCCs. The frequency of p53 mutations was consistent with high prevalence of HBV and a moderate aflatoxin B1 (AFB1) exposure in our area. CONCLUSIONS The results suggest that AFB1 acts synergistically with HBV in the generation of p53 mutations. Furthermore,dietary exposure to AFB1 may mainly contribute to the tumor specific mutation at codon 249,while HBV may account for other scattered mutations in HCC.展开更多
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 a...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 .展开更多
AIM To investigate hepatocarcinogenesis by detecting the effect of HCV NS 3 protein on P53 protein expression in hepatocellular carcinoma (HCC) and pericarcinomatous liver tissue (PCLT). METHODS The expression of ...AIM To investigate hepatocarcinogenesis by detecting the effect of HCV NS 3 protein on P53 protein expression in hepatocellular carcinoma (HCC) and pericarcinomatous liver tissue (PCLT). METHODS The expression of HCV NS 3 and P53 protein was detected with immunohistochemical technique (SP method) in specimens of HCC and PCLT from 47 patients with negative HBV. RESULTS The positive rate of HCV NS 3 protein was lower in HCC (62%) than in PCLT (83%) ( P <0 025). The better differentiaton of cancer cells, the stronger expression of HCV NS 3 protein ( P <0 025). The positive rate of P53 protein in HCC (81%) was higher than in PCLT (47%) ( P <0 025). The worse differentiaton of cancer cells, the stronger expression of P53 protein ( P <0 05). The P53 protein expression was not correlated with the HCV NS 3 protein expression in HCC ( P >0 5), whereas their expression was closely related to PCLT ( P <0 01), and the expression rate of P53 protein in the cases of positive HCV NS 3 protein was higher than that in the cases of negative HCV NS 3 protein. CONCLUSION HCV NS 3 protein may exert its hepatocarcinogenic effect in early stage on host cells by endogenous pathway which may bring about mutation of p53 gene and transformation of hepatocytes.展开更多
AIM To investigate the effect of Boschniakiarossica(BR)extract on expression of GST-P,p53 and p21<sup>ras</sup>proteins in early stage of chemicalhepatocarcinogenesis in rats and its anti-inflammatory ac...AIM To investigate the effect of Boschniakiarossica(BR)extract on expression of GST-P,p53 and p21<sup>ras</sup>proteins in early stage of chemicalhepatocarcinogenesis in rats and its anti-inflammatory activities.METHODS The expression of tumor marker-placental form glutathione S-transferase(GST-P),p53 and p21<sup>ras</sup>proteins were investigated byimmunohistochemical techniques and ABCmethod.Anti-inflammatory activities of BR werestudied by xylene and croton oil-induced mouseear edema,carrageenin,histamine and hotscald-induced rat pow edema,adjuvant-inducedrat arthritis and cotton pellet-induced mousegranuloma formation methods.RESULTS The 500 mg/kg of BR-H<sub>2</sub>O extractfractionated from BR-Methanol extract hadinhibitory effect on the formation of DEN-inducedGST-P-positive foci in rat liver(GST-P stainingwas 78% positive in DEN+AAF group vs 20%positive in DEN+AAF+BR group,P【0.05)andthe expression of mutant p53 and p21<sup>ras</sup>proteinwas lower than that of hepatic preneoplasticlesions(33% and 22% positive respectively inDEN+AAF group vs negative in DEN+AAF+BRgroup).Both CH<sub>2</sub>Cl<sub>2</sub> and H<sub>2</sub>O extracts from BRhad anti-inflamatory effect in xylene and crotonoil-induced mouse ear edema(inhibitory rateswere 26%-29% and 35%-59%,respectively). BR-H<sub>2</sub>O extract exhibited inhibitory effect incarrageenin,histamine and hot scald-inducedhind paw edema and adjuvant-induced arthritis inrats and cotton pellet-induced granulomaformation in mice.CONCLUSION BR extract exhibited inhibitory effect on formation of preneoplastic hepatic foci in early stage of rat chemical hepato-carcinogenesis. Both CH<sub>2</sub>CI<sub>2</sub> and H<sub>2</sub>O extracts from BR exerted anti-inflammatory effect in rats and mice.展开更多
AIM: To investigate the expression of Cyclooxygenase-2 (COX-2), proliferating cell nuclear antigen (PCNA), Ki-67 and p53 in gastrointestinal stromal tumors (GISTs) and its relationship with histopathological parameter...AIM: To investigate the expression of Cyclooxygenase-2 (COX-2), proliferating cell nuclear antigen (PCNA), Ki-67 and p53 in gastrointestinal stromal tumors (GISTs) and its relationship with histopathological parameters. METHODS: Twenty-five GISTs were examined by light microscopy and immunohistochemistry. c-kit, CD34, SMA, S-100 protein, COX-2, PCNA, Ki-67 and p53 were detected immunohistochemically and the relationship was evaluated among histopathologic parameters such as mitotic index (MI), tumor grade, tumor size, COX-2, PCNA, Ki-67 and p53. RESULTS: COX-2 protein expression was found in 19 of 25 (76%) of the tumors, and expression was noted in the cytoplasm of the tumor cells. p53 was significantly related to MI and tumor grade but no relationship was found between COX-2, proliferation markers and MI, tumor grade and tumor size. CONCLUSION: COX-2 is expressed in most GISTs and it may play an important role in the proliferation and progression of these tumors or a useful marker to identify GIST. Although immunohistochemical assessment of p53 can be used for distinguishing the risk groups of GISTs, tumor size and mitotic rate should be considered at the same time.展开更多
AIM To evaluate the relationship between expression of ras, p53, bcl 2 gene products, and hepatocarcinogenesis since endotoxemia produced from lipopolysaccharide admi nistration and/or the hypophagocytic state of ...AIM To evaluate the relationship between expression of ras, p53, bcl 2 gene products, and hepatocarcinogenesis since endotoxemia produced from lipopolysaccharide admi nistration and/or the hypophagocytic state of splenectomy significantly accelerated hepatocarcinogenesis induced by thioacetamide. 〖WTH4〗METHODS〓〖WTXFZ〗The hepatocarcinoma model was induced by oral intake of 0 03% thioacetamide for six months. During the induction of hepatocarcinoma model, rats were additionally treated with splenectomy and/or lipopolysaccharide administration. The techniques of flow cytometry, immunohistochemistry and immunoelectronmicroscopy were applied to quantitative analysis of the expression of oncogene proteins. RESULTS In this model system, overexpression of ras p21 protein mainly occurred on precancerous cell population or in early stage of hepatocyte transformation. And the levels of ras p21 declined when nuclear DNA aneuploid increased. Expression of bcl 2 protein slowly and steadily rose with more hepatocytes staying in S+G2M phases as the hepatocarcinoma became more malignant. P53 was moderately expressed during the hepatocarcinogenesis. There was no statistical correlation between endotoxemia levels and the changes of ras, p53 and bcl 2 gene products. CONCLUSION Over expression of oncogene ras p21 was likely to be a precursor of the premalignant hepatocytes and it might be responsible for the initiation of hepatocarcinogenesis. Bcl 2 protein expression is proportional to the severity of the malignancies. P53 may be a key pathway on the transformation and development of hepatocarcinoma. This study confirmed the hypothesis that there are multiple genes and multiple steps involved in hepatocarcinogenesis. Expressions of oncogene proteins reflected the properties of the premalignant and malignant cells, but not directly related to endotoxemia statistically.[JP]展开更多
AIM:To investigate the role of expressions of Ki-67, p53,epidermal growth factor receptor(EGFR)and cyclooxygenase-2(COX-2)in gastrointestinal stromal tumor(GIST)grading and prognosis. METHODS:Tumor tissue was collecte...AIM:To investigate the role of expressions of Ki-67, p53,epidermal growth factor receptor(EGFR)and cyclooxygenase-2(COX-2)in gastrointestinal stromal tumor(GIST)grading and prognosis. METHODS:Tumor tissue was collected retrospectively from 96 patients with GIST.Antibodies against Ki-67, p53,EGFR and COX-2 were used for immunohistochemical staining.Tumor grading was designated according to a consensus system and the staining was quantified in 3 categories for each antibody in the statistical analysis. RESULTS:The Ki-67 expression in GISTs was significantly associated with the size of the tumors,mitotic rate and the risk of malignancy(x2=15.51,P=0.02; x2=22.27,P<0.001;x2=20.05;P<0.001).The p53 expression was also significantly correlated with mitotic rate and the risk of malignancy(x2=9.92,P= 0.04;x2=9.97;P=0.04).Over-expression of Ki-67 was strongly correlated with poor survival(x2=10.44, P=0.006),but no correlation was found between the expression of p53,EGFR or COX-2 and survival. Multivariate analysis further demonstrated that Ki-67 expression(relative risk=15.78,95%CI:4.25-59.37) could be used as an independent prognostic value for GIST patients.Adjuvant imatinib therapy could improve clinical outcomes in the patients with high risk and intermediate risk of recurrence after complete tumor resections(median survival time:52 mo vs 37 mo, x2=7.618,P=0.006). CONCLUSION:Our results indicated that the expression of Ki-67 could be used as an independent prognostic factor for GIST patients.展开更多
AIM: To examine the expression of p53 and vascular endothelial growth factor (VEGF) as well as microvessel count (MVC) and to investigate the role of VEGF as an angiogenic marker and the possible role of p53 in t...AIM: To examine the expression of p53 and vascular endothelial growth factor (VEGF) as well as microvessel count (MVC) and to investigate the role of VEGF as an angiogenic marker and the possible role of p53 in the regulation of angiogenesis in human gallbladder carcinoma. METHODS: Surgically resected specimens of 49 gallbladder carcinomas were studied by immunohistochemical staining for p53 protein, VEGF, and factor VIII-related antigen. VEGF expression and mutant p53 expression were then correlated with Nevin stage, differentiation grade, MVC, and lymph node metastasis. RESULTS: Positive p53 protein and VEGF expressions were found in 61.2% and 63.3% of tumors, respectively. p53 and VEGF staining status was identical in 55.1% of tumors. The Nevin staging of p53- or VEGF-positive tumors was significantly later than that of negative tumors. The MVC in p53- or VEGF-positive tumors was significantly higher than that in negative tumors, and MVC in both p53- and VEGF-negative tumors was significantly lower than that in the other subgroups. CONCLUSION: Our findings suggest that pS3-VEGF pathway can regulate tumor angiogenesis in human gallbladder carcinoma. Combined analysis of p53 and VEGF expression might be useful for predicting the tumor vascularity of gallbladder cancer.展开更多
AIM: To investigate the relationship between the chemotherapeutic drug efficacy and the expression of P-glycoprotein (PGP) and p53 protein in advanced hepatocellular carcinoma (HCC). METHODS: The study was condu...AIM: To investigate the relationship between the chemotherapeutic drug efficacy and the expression of P-glycoprotein (PGP) and p53 protein in advanced hepatocellular carcinoma (HCC). METHODS: The study was conducted on 41 patients with advanced HCC who were treated by repeated arterial infusion chemotherapy. Biopsy specimens from the tumor were collected before the start of treatment in all the patients, and the specimens were stored frozen until immunohistochemical staining, which was performed after the start of treatment, to detect PGP and p53 protein expressions. Twenty of the fortyone patients were treated with an anthracycline drug (epirubicin hydrochloride; anthracycline group), and the remaining 21 were treated with a non-anthracycline drug (mitoxantrone hydrochloride in 11 patients and carboplatin in 10 patients; non-anthracycline group). The relationship between the chemotherapeutic efficacy and the results of immunostaining were compared between the two groups. RESULTS: Before the start of the treatment, PGPpositive rate was 90.2% (strongly-positive, 36.6%) and p53 protein-positive rate was 34.1% (strongly-positive, 19.5%). In the anthracycline group, the response rate was 40.0%. The number of patients showing poor response to the treatment was significantly larger in the patients with strongly positive PGP expression (P= 0.005), and their prognoses were poor (P= 0.001). in the nonanthracycline group, the response rate was 42.9%,and there was no significant relationship between the chemotherapeutic drug efficacy and the PGP or p53 protein expression. When only the data from the 11 patients treated with anthraquinone drug, mitoxantrone, were analyzed, however, the number of patients who showed poor response to treatment was significantly higher among the p53-positive patients (P= 0.012), irrespective of the survival outcome. CONCLUSION: The chemotherapeutic efficacy with an anthracycline drug for advanced HCC can be predicted by immunohistochemical analysis of PGP expression. Similarly, immunostaining to evaluate p53 protein may be useful to predict the response in patients treated with an anthraquinone drug.展开更多
AIMS To determine the clinical significance of P53 protein ex-pression in colorectal carcinoma.METHODS The expression of P53 protein in 92 colorectal car-cinomas was examined using the monoclonal antibody PAb 1801.Cor...AIMS To determine the clinical significance of P53 protein ex-pression in colorectal carcinoma.METHODS The expression of P53 protein in 92 colorectal car-cinomas was examined using the monoclonal antibody PAb 1801.Correlation between P53 protein expression and prognosis in col-orectal carcinoma was analyzed using log-rank test.RESULTS The frequency of P53 protein expression was 57.61%,corresponding with Dukes’ staging.Analysis of survivordata demonstrated that the survival rate of colorectal carcinomawith positive P53 protein group was lower than that of negativeP53 protein group.CONCLUSIONS We conclude that the expression of P53 pro-tein is correlated with poor prognosis in colorectal carcinoma.展开更多
Background: Esophageal squamous cell carcinoma(ESCC) is a leading cause of cancer?related death, and new prognostic biomarkers are urgently needed. Apoptosis?stimulating P53?binding protein 1(ASPP1) and 2(ASPP2) have ...Background: Esophageal squamous cell carcinoma(ESCC) is a leading cause of cancer?related death, and new prognostic biomarkers are urgently needed. Apoptosis?stimulating P53?binding protein 1(ASPP1) and 2(ASPP2) have been reported to play important roles in the development, progression, metastasis, and prognosis of cancers, but their roles in ESCC have not been elucidated. In this study, we examined the expression of ASPP1 and ASPP2 in ESCC to evaluate their prognostic values.Methods: The protein expression of ASPP1, ASPP2, and P53 in 175 specimens of ESCC was detected using immuno?histochemical staining; their expression in cancerous and noncancerous tissues was scored according to the stain?ing intensity and the percentage of stained cells. The associations of ASPP1, ASPP2, and P53 with clinicopathologic parameters, overall survival(OS), and disease?free survival(DFS) were analyzed.Results: The protein expression levels of ASPP2 and P53 were significantly higher in cancerous tissues than in paired noncancerous tissues(P < 0.001), whereas the expression levels of ASPP1 in the two groups were similar. In ESCCs, ASPP1 expression was significantly associated with histological differentiation(P = 0.002) and invasive depth(P = 0.014); ASPP2 expression was associated with age(P = 0.029) and histological differentiation(P < 0.001); and P53 expression was associated with age(P and P53 expression. Survival an= 0.021) and tumor size(P alysis revealed that high AS= 0.040). No correlations were found between ASPP1, ASPP2,PP2 expression was significantly associated with increased 5?year OS(P = 0.001) and DFS rates(P ate of ESCC patients(= 0.010) and that high P53 expression was significantly associated with a reduced 5?year DFS rP atio(HR): 0.541, 9= 0.015). Multivariate Cox analysis indicated that ASPP2 was an inde?pendent predictor of OS [hazard r5% confidence interval(CI) 0.363–0.804] and DFS(HR: 0.599, 95% CI 0.404–0.888) of ESCC patients and that P53 was an independent predictor of DFS(HR: 2.161, 95% CI 1.100–4.245).Conclusions: ASPP1 might be involved in the progression of ESCC, and ASPP2 was a potential prognostic biomarker of ESCC and should be evaluated in future studies.展开更多
AIM: To reveal the insight mechanism of liver metastasis in uveal melanoma, we investigated cell functions of microRNA-21 in three different uveal melanoma cell lines and analyze the relationship of target gene p53 a...AIM: To reveal the insight mechanism of liver metastasis in uveal melanoma, we investigated cell functions of microRNA-21 in three different uveal melanoma cell lines and analyze the relationship of target gene p53 and its downstream targets which been found significant expression in our previous study.METHODS: Quantitative real-time polymerase chain reaction (qRT-PCR) was used to detect microRNA-21 expression in normal uveal tissue and uveal melanoma cell lines. Lenti-virus expression system was used to construct OCM-1, MuM-2B and M619 cell line with stable overexpression and inhibition of microRNA-21. In vitro cell function tests such as cell proliferation, cell apoptosis, cell circle and abilities of migration and invasion were examined by MTT, BrdU assay, flow cytometry, transwell assay and Matrigel invasion assay respectively. The target gene was predicted by bioinformatics and confirmed by using a dual luciferase reporter assay. The expression of p53 and its suspected downstream targets LIM and SH3 protein 1 (LASP1) and Glutathione S Transferase pi (GST-Pi) were determined by qRT-PCR in mRNA level and western blotting analysis in protein level. Finally, the effect of microRNA-21 in a xenograft tumor model was assessed in four-week-old BALB/c nude mice. RESULTS: Compared to normal uveal melanoma, expressions of microRNA-21 were significantly higher in uveal melanoma cell lines. Overexpression of microRNA-21 promoted proliferation, migration, and invasion of OCM-1, M619 and MuM-2B cells, while inhibition of microRNA-21 reveal opposite effects. Wild type p53 was identified as a target gene of microRNA-21-3p, and proved by dual luciferase reporter assay. Up-regulated microRNA-21 inhibited the expression of wild type p53 gene, and the increased expression of LASP1 in mRNA level and protein level, while down-regulated microRNA-21 presented opposite way. However, GST-pi showed the potential pattern as expected, but relative mRNA level showed no statistically significant difference in OCM-1 cells. Furthermore, the mRNA expression of GST-pi was decreased in microRNA-21 overexpressing MuM-2B, and increased in M619 cells with inhibition of microRNA-21. In vivo, inhibition of microRNA-21 reduced tumor growth with statistically significant difference.CONCLUSION: These findings provide novel insight into molecular etiology of microRNA-21 in uveal melanoma cell lines, and suggest that microRNA-21 might be a potential candidate for the diagnosis and prognostic factor of human uveal melanoma in future.展开更多
基金the National Natural Science Foundation of China(Grant No.82072580).
文摘The abnormality of the p53 tumor suppressor is crucial in lung cancer development,because p53 regulates target gene promoters to combat cancer.Recent studies have shown extensive p53 binding to enhancer elements.However,whether p53 exerts a tumor suppressor role by shaping the enhancer landscape remains poorly understood.In the current study,we employed several functional genomics approaches to assess the enhancer activity at p53 binding sites throughout the genome based on our established TP53 knockout(KO)human bronchial epithelial cells(BEAS-2B).A total of 943 active regular enhancers and 370 super-enhancers(SEs)disappeared upon the deletion of p53,indicating that p53 modulates the activity of hundreds of enhancer elements.We found that one p53-dependent SE,located on chromosome 9 and designated as KLF4-SE,regulated the expression of the Krüppel-like factor 4(KLF4)gene.Furthermore,the deletion of p53 significantly decreased the KLF4-SE enhancer activity and the KLF4 expression,but increased colony formation ability in the nitrosamines 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone-induced cell transformation model.Subsequently,in TP53 KO cells,the overexpression of KLF4 partially reversed the increased clonogenic capacity caused by p53 deficiency.Consistently,KLF4 expression also decreased in lung cancer tissues and cell lines.It appeared that overexpression of KLF4 significantly suppressed the proliferation and migration of lung cancer cells.Collectively,our results suggest that the regulation of enhancer formation and activity by p53 is an integral component of the p53 tumor suppressor function.Therefore,our findings offer some novel insights into the regulation mechanism of p53 in lung oncogenesis and introduce a new strategy for screening therapeutic targets.
文摘AIM: Overexpression of tumor protein p53-induced nudear protein 1 (TP53INP1) induces G1 cell cycle arrest and increases p53-mediated apoptosis. To clarify the clinical importance of TP53INP1, we analyzed TP53INP1 and p53 expression in gastric cancer, METHODS: TP53INP1 and p53 expression were examined using immunohistochemistry in 142 cases of gastric cancer. The apoptosis of gastric cancer cells was analyzed using the TUNEL method. The relationship between the expression of TP53INP1 and clinicopathological factors was statistically analyzed. RESULTS: TP53INP1 was expressed in 98% (139/142 cases) of non-cancerous gastric tissues and was downexpressed in 64% (91/142 cases) of gastric cancer lesions from the same patients. TP53INP1 expression was significantly decreased (43.9%) in poorly differentiated adenocarcinoma compared with well or moderately differentiated adenocarcinoma (81.6%). Cancers invading the submucosa or deeper showed lower positively (59.1%) compared with mucosal cancers (85.2%). Decrease or loss of TP53INP1 expression was significantly correlated with lymphatic invasion (54.3% vs 82.0% without lymphatic invasion) and node-positive patients (31.3% vs 68.3% in node-negative patients). P53 was expressed in 68 (47.9%) patients of gastric cancer, whereas it was absent in normal gastric tissues. A significant association was also observed between TP53INP1 status and the level of apoptosis in tumor cells: the apoptotic index in TP53INP1-positive tissues was significantly higher than that in TP53INP41-negative portions. Finally, when survival data were analyzed, loss of TP53INP1 expression had a significant effect in predicting a poor prognosis (P= 0.0006).CONCLUSION: TPS3INP1-positive rate decreases with the progression of gastric cancer. TPS3INP1 protein negativity is significantly associated with aggressive pathological phenotypes of gastric cancer. TPS3INP1 is related to the apoptosis of gastric cancer cells. The decreased expression of the TPS3INP1 protein may reflect the malignant grade of gastric cancer and is regarded as an adverse prognostic factor.
文摘AIMS To examine the prevalance of p53 mutations in hepatocellular carcinoma (HCC) from Chongqing area and the relationship between the p53 mutations and clinicopathological features of HCC,as well as the risk factors. METHODS The overexpression and point mutations of tumor suppressor gene p53 in 38 cases of HCC were detected by a sensitive antigen retrieval fluid (ARF) immunohistochemical method and polymerase chain re- action(PCR)-restriction fragment length polymorphism (RFLP),and single strand conformation polymorphism (SSCP)-silver staining analysis. RESULTS The results showed that 16 of 38 HCCs had positive p53 protein (42.1%),7 HCCs had p53 mutation at 249 (18.4 % ) and 2 HCCS had point muta- tion within exon 7 other than 249. Among 9 cases of HCC with mutations,8 cases demonstrated positive p53 protein,its coincidental rate was 88.9%. The overexpression and mutations of p53 were significantly related to the differentiation and metastasis of HCCs. The frequency of p53 mutations was consistent with high prevalence of HBV and a moderate aflatoxin B1 (AFB1) exposure in our area. CONCLUSIONS The results suggest that AFB1 acts synergistically with HBV in the generation of p53 mutations. Furthermore,dietary exposure to AFB1 may mainly contribute to the tumor specific mutation at codon 249,while HBV may account for other scattered mutations in HCC.
基金Supported by the Medical Research Foundation of Guangdong Province,No.1997423
文摘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 .
文摘AIM To investigate hepatocarcinogenesis by detecting the effect of HCV NS 3 protein on P53 protein expression in hepatocellular carcinoma (HCC) and pericarcinomatous liver tissue (PCLT). METHODS The expression of HCV NS 3 and P53 protein was detected with immunohistochemical technique (SP method) in specimens of HCC and PCLT from 47 patients with negative HBV. RESULTS The positive rate of HCV NS 3 protein was lower in HCC (62%) than in PCLT (83%) ( P <0 025). The better differentiaton of cancer cells, the stronger expression of HCV NS 3 protein ( P <0 025). The positive rate of P53 protein in HCC (81%) was higher than in PCLT (47%) ( P <0 025). The worse differentiaton of cancer cells, the stronger expression of P53 protein ( P <0 05). The P53 protein expression was not correlated with the HCV NS 3 protein expression in HCC ( P >0 5), whereas their expression was closely related to PCLT ( P <0 01), and the expression rate of P53 protein in the cases of positive HCV NS 3 protein was higher than that in the cases of negative HCV NS 3 protein. CONCLUSION HCV NS 3 protein may exert its hepatocarcinogenic effect in early stage on host cells by endogenous pathway which may bring about mutation of p53 gene and transformation of hepatocytes.
基金the National Natural Science Foundation of China,No.39660021
文摘AIM To investigate the effect of Boschniakiarossica(BR)extract on expression of GST-P,p53 and p21<sup>ras</sup>proteins in early stage of chemicalhepatocarcinogenesis in rats and its anti-inflammatory activities.METHODS The expression of tumor marker-placental form glutathione S-transferase(GST-P),p53 and p21<sup>ras</sup>proteins were investigated byimmunohistochemical techniques and ABCmethod.Anti-inflammatory activities of BR werestudied by xylene and croton oil-induced mouseear edema,carrageenin,histamine and hotscald-induced rat pow edema,adjuvant-inducedrat arthritis and cotton pellet-induced mousegranuloma formation methods.RESULTS The 500 mg/kg of BR-H<sub>2</sub>O extractfractionated from BR-Methanol extract hadinhibitory effect on the formation of DEN-inducedGST-P-positive foci in rat liver(GST-P stainingwas 78% positive in DEN+AAF group vs 20%positive in DEN+AAF+BR group,P【0.05)andthe expression of mutant p53 and p21<sup>ras</sup>proteinwas lower than that of hepatic preneoplasticlesions(33% and 22% positive respectively inDEN+AAF group vs negative in DEN+AAF+BRgroup).Both CH<sub>2</sub>Cl<sub>2</sub> and H<sub>2</sub>O extracts from BRhad anti-inflamatory effect in xylene and crotonoil-induced mouse ear edema(inhibitory rateswere 26%-29% and 35%-59%,respectively). BR-H<sub>2</sub>O extract exhibited inhibitory effect incarrageenin,histamine and hot scald-inducedhind paw edema and adjuvant-induced arthritis inrats and cotton pellet-induced granulomaformation in mice.CONCLUSION BR extract exhibited inhibitory effect on formation of preneoplastic hepatic foci in early stage of rat chemical hepato-carcinogenesis. Both CH<sub>2</sub>CI<sub>2</sub> and H<sub>2</sub>O extracts from BR exerted anti-inflammatory effect in rats and mice.
文摘AIM: To investigate the expression of Cyclooxygenase-2 (COX-2), proliferating cell nuclear antigen (PCNA), Ki-67 and p53 in gastrointestinal stromal tumors (GISTs) and its relationship with histopathological parameters. METHODS: Twenty-five GISTs were examined by light microscopy and immunohistochemistry. c-kit, CD34, SMA, S-100 protein, COX-2, PCNA, Ki-67 and p53 were detected immunohistochemically and the relationship was evaluated among histopathologic parameters such as mitotic index (MI), tumor grade, tumor size, COX-2, PCNA, Ki-67 and p53. RESULTS: COX-2 protein expression was found in 19 of 25 (76%) of the tumors, and expression was noted in the cytoplasm of the tumor cells. p53 was significantly related to MI and tumor grade but no relationship was found between COX-2, proliferation markers and MI, tumor grade and tumor size. CONCLUSION: COX-2 is expressed in most GISTs and it may play an important role in the proliferation and progression of these tumors or a useful marker to identify GIST. Although immunohistochemical assessment of p53 can be used for distinguishing the risk groups of GISTs, tumor size and mitotic rate should be considered at the same time.
文摘AIM To evaluate the relationship between expression of ras, p53, bcl 2 gene products, and hepatocarcinogenesis since endotoxemia produced from lipopolysaccharide admi nistration and/or the hypophagocytic state of splenectomy significantly accelerated hepatocarcinogenesis induced by thioacetamide. 〖WTH4〗METHODS〓〖WTXFZ〗The hepatocarcinoma model was induced by oral intake of 0 03% thioacetamide for six months. During the induction of hepatocarcinoma model, rats were additionally treated with splenectomy and/or lipopolysaccharide administration. The techniques of flow cytometry, immunohistochemistry and immunoelectronmicroscopy were applied to quantitative analysis of the expression of oncogene proteins. RESULTS In this model system, overexpression of ras p21 protein mainly occurred on precancerous cell population or in early stage of hepatocyte transformation. And the levels of ras p21 declined when nuclear DNA aneuploid increased. Expression of bcl 2 protein slowly and steadily rose with more hepatocytes staying in S+G2M phases as the hepatocarcinoma became more malignant. P53 was moderately expressed during the hepatocarcinogenesis. There was no statistical correlation between endotoxemia levels and the changes of ras, p53 and bcl 2 gene products. CONCLUSION Over expression of oncogene ras p21 was likely to be a precursor of the premalignant hepatocytes and it might be responsible for the initiation of hepatocarcinogenesis. Bcl 2 protein expression is proportional to the severity of the malignancies. P53 may be a key pathway on the transformation and development of hepatocarcinoma. This study confirmed the hypothesis that there are multiple genes and multiple steps involved in hepatocarcinogenesis. Expressions of oncogene proteins reflected the properties of the premalignant and malignant cells, but not directly related to endotoxemia statistically.[JP]
文摘AIM:To investigate the role of expressions of Ki-67, p53,epidermal growth factor receptor(EGFR)and cyclooxygenase-2(COX-2)in gastrointestinal stromal tumor(GIST)grading and prognosis. METHODS:Tumor tissue was collected retrospectively from 96 patients with GIST.Antibodies against Ki-67, p53,EGFR and COX-2 were used for immunohistochemical staining.Tumor grading was designated according to a consensus system and the staining was quantified in 3 categories for each antibody in the statistical analysis. RESULTS:The Ki-67 expression in GISTs was significantly associated with the size of the tumors,mitotic rate and the risk of malignancy(x2=15.51,P=0.02; x2=22.27,P<0.001;x2=20.05;P<0.001).The p53 expression was also significantly correlated with mitotic rate and the risk of malignancy(x2=9.92,P= 0.04;x2=9.97;P=0.04).Over-expression of Ki-67 was strongly correlated with poor survival(x2=10.44, P=0.006),but no correlation was found between the expression of p53,EGFR or COX-2 and survival. Multivariate analysis further demonstrated that Ki-67 expression(relative risk=15.78,95%CI:4.25-59.37) could be used as an independent prognostic value for GIST patients.Adjuvant imatinib therapy could improve clinical outcomes in the patients with high risk and intermediate risk of recurrence after complete tumor resections(median survival time:52 mo vs 37 mo, x2=7.618,P=0.006). CONCLUSION:Our results indicated that the expression of Ki-67 could be used as an independent prognostic factor for GIST patients.
文摘AIM: To examine the expression of p53 and vascular endothelial growth factor (VEGF) as well as microvessel count (MVC) and to investigate the role of VEGF as an angiogenic marker and the possible role of p53 in the regulation of angiogenesis in human gallbladder carcinoma. METHODS: Surgically resected specimens of 49 gallbladder carcinomas were studied by immunohistochemical staining for p53 protein, VEGF, and factor VIII-related antigen. VEGF expression and mutant p53 expression were then correlated with Nevin stage, differentiation grade, MVC, and lymph node metastasis. RESULTS: Positive p53 protein and VEGF expressions were found in 61.2% and 63.3% of tumors, respectively. p53 and VEGF staining status was identical in 55.1% of tumors. The Nevin staging of p53- or VEGF-positive tumors was significantly later than that of negative tumors. The MVC in p53- or VEGF-positive tumors was significantly higher than that in negative tumors, and MVC in both p53- and VEGF-negative tumors was significantly lower than that in the other subgroups. CONCLUSION: Our findings suggest that pS3-VEGF pathway can regulate tumor angiogenesis in human gallbladder carcinoma. Combined analysis of p53 and VEGF expression might be useful for predicting the tumor vascularity of gallbladder cancer.
文摘AIM: To investigate the relationship between the chemotherapeutic drug efficacy and the expression of P-glycoprotein (PGP) and p53 protein in advanced hepatocellular carcinoma (HCC). METHODS: The study was conducted on 41 patients with advanced HCC who were treated by repeated arterial infusion chemotherapy. Biopsy specimens from the tumor were collected before the start of treatment in all the patients, and the specimens were stored frozen until immunohistochemical staining, which was performed after the start of treatment, to detect PGP and p53 protein expressions. Twenty of the fortyone patients were treated with an anthracycline drug (epirubicin hydrochloride; anthracycline group), and the remaining 21 were treated with a non-anthracycline drug (mitoxantrone hydrochloride in 11 patients and carboplatin in 10 patients; non-anthracycline group). The relationship between the chemotherapeutic efficacy and the results of immunostaining were compared between the two groups. RESULTS: Before the start of the treatment, PGPpositive rate was 90.2% (strongly-positive, 36.6%) and p53 protein-positive rate was 34.1% (strongly-positive, 19.5%). In the anthracycline group, the response rate was 40.0%. The number of patients showing poor response to the treatment was significantly larger in the patients with strongly positive PGP expression (P= 0.005), and their prognoses were poor (P= 0.001). in the nonanthracycline group, the response rate was 42.9%,and there was no significant relationship between the chemotherapeutic drug efficacy and the PGP or p53 protein expression. When only the data from the 11 patients treated with anthraquinone drug, mitoxantrone, were analyzed, however, the number of patients who showed poor response to treatment was significantly higher among the p53-positive patients (P= 0.012), irrespective of the survival outcome. CONCLUSION: The chemotherapeutic efficacy with an anthracycline drug for advanced HCC can be predicted by immunohistochemical analysis of PGP expression. Similarly, immunostaining to evaluate p53 protein may be useful to predict the response in patients treated with an anthraquinone drug.
文摘AIMS To determine the clinical significance of P53 protein ex-pression in colorectal carcinoma.METHODS The expression of P53 protein in 92 colorectal car-cinomas was examined using the monoclonal antibody PAb 1801.Correlation between P53 protein expression and prognosis in col-orectal carcinoma was analyzed using log-rank test.RESULTS The frequency of P53 protein expression was 57.61%,corresponding with Dukes’ staging.Analysis of survivordata demonstrated that the survival rate of colorectal carcinomawith positive P53 protein group was lower than that of negativeP53 protein group.CONCLUSIONS We conclude that the expression of P53 pro-tein is correlated with poor prognosis in colorectal carcinoma.
基金supported by grants from the Research Fund of Guangdong Esophageal Cancer Institute of China(Grant No:M201412 for H-YW)the Research Fund of the State Key Laboratory of Oncology in South China(to H-YW)
文摘Background: Esophageal squamous cell carcinoma(ESCC) is a leading cause of cancer?related death, and new prognostic biomarkers are urgently needed. Apoptosis?stimulating P53?binding protein 1(ASPP1) and 2(ASPP2) have been reported to play important roles in the development, progression, metastasis, and prognosis of cancers, but their roles in ESCC have not been elucidated. In this study, we examined the expression of ASPP1 and ASPP2 in ESCC to evaluate their prognostic values.Methods: The protein expression of ASPP1, ASPP2, and P53 in 175 specimens of ESCC was detected using immuno?histochemical staining; their expression in cancerous and noncancerous tissues was scored according to the stain?ing intensity and the percentage of stained cells. The associations of ASPP1, ASPP2, and P53 with clinicopathologic parameters, overall survival(OS), and disease?free survival(DFS) were analyzed.Results: The protein expression levels of ASPP2 and P53 were significantly higher in cancerous tissues than in paired noncancerous tissues(P < 0.001), whereas the expression levels of ASPP1 in the two groups were similar. In ESCCs, ASPP1 expression was significantly associated with histological differentiation(P = 0.002) and invasive depth(P = 0.014); ASPP2 expression was associated with age(P = 0.029) and histological differentiation(P < 0.001); and P53 expression was associated with age(P and P53 expression. Survival an= 0.021) and tumor size(P alysis revealed that high AS= 0.040). No correlations were found between ASPP1, ASPP2,PP2 expression was significantly associated with increased 5?year OS(P = 0.001) and DFS rates(P ate of ESCC patients(= 0.010) and that high P53 expression was significantly associated with a reduced 5?year DFS rP atio(HR): 0.541, 9= 0.015). Multivariate Cox analysis indicated that ASPP2 was an inde?pendent predictor of OS [hazard r5% confidence interval(CI) 0.363–0.804] and DFS(HR: 0.599, 95% CI 0.404–0.888) of ESCC patients and that P53 was an independent predictor of DFS(HR: 2.161, 95% CI 1.100–4.245).Conclusions: ASPP1 might be involved in the progression of ESCC, and ASPP2 was a potential prognostic biomarker of ESCC and should be evaluated in future studies.
基金Supported by the National Natural Science Foundation of China (No.81570891 No.81272981)+3 种基金Beijing Natural Science Foundation (No.7151003)Advanced Health Care Professionals Development Project of Beijing Municipal Health Bureau (No.2014-2-003)the Capital Health Research and Development of Special (No.2016-1-2051)Hospitals’ Ascent Plan (No.DFL20150201)
文摘AIM: To reveal the insight mechanism of liver metastasis in uveal melanoma, we investigated cell functions of microRNA-21 in three different uveal melanoma cell lines and analyze the relationship of target gene p53 and its downstream targets which been found significant expression in our previous study.METHODS: Quantitative real-time polymerase chain reaction (qRT-PCR) was used to detect microRNA-21 expression in normal uveal tissue and uveal melanoma cell lines. Lenti-virus expression system was used to construct OCM-1, MuM-2B and M619 cell line with stable overexpression and inhibition of microRNA-21. In vitro cell function tests such as cell proliferation, cell apoptosis, cell circle and abilities of migration and invasion were examined by MTT, BrdU assay, flow cytometry, transwell assay and Matrigel invasion assay respectively. The target gene was predicted by bioinformatics and confirmed by using a dual luciferase reporter assay. The expression of p53 and its suspected downstream targets LIM and SH3 protein 1 (LASP1) and Glutathione S Transferase pi (GST-Pi) were determined by qRT-PCR in mRNA level and western blotting analysis in protein level. Finally, the effect of microRNA-21 in a xenograft tumor model was assessed in four-week-old BALB/c nude mice. RESULTS: Compared to normal uveal melanoma, expressions of microRNA-21 were significantly higher in uveal melanoma cell lines. Overexpression of microRNA-21 promoted proliferation, migration, and invasion of OCM-1, M619 and MuM-2B cells, while inhibition of microRNA-21 reveal opposite effects. Wild type p53 was identified as a target gene of microRNA-21-3p, and proved by dual luciferase reporter assay. Up-regulated microRNA-21 inhibited the expression of wild type p53 gene, and the increased expression of LASP1 in mRNA level and protein level, while down-regulated microRNA-21 presented opposite way. However, GST-pi showed the potential pattern as expected, but relative mRNA level showed no statistically significant difference in OCM-1 cells. Furthermore, the mRNA expression of GST-pi was decreased in microRNA-21 overexpressing MuM-2B, and increased in M619 cells with inhibition of microRNA-21. In vivo, inhibition of microRNA-21 reduced tumor growth with statistically significant difference.CONCLUSION: These findings provide novel insight into molecular etiology of microRNA-21 in uveal melanoma cell lines, and suggest that microRNA-21 might be a potential candidate for the diagnosis and prognostic factor of human uveal melanoma in future.