INTRODUCTIONHepatocellular carcinoma (HCC) is one of the mostcommon human malignancies worldwide[1,2], and isclosely associated with infection of HBV and HCVand contamination of aflatoxin B1[3-6]. Althoughthe molecula...INTRODUCTIONHepatocellular carcinoma (HCC) is one of the mostcommon human malignancies worldwide[1,2], and isclosely associated with infection of HBV and HCVand contamination of aflatoxin B1[3-6]. Althoughthe molecular mechanisms of hepatocarcinogenesisremain poorly understood, an increasing number ofgenetic abnormalities have been recognized[7-10],for example, the p16 gene[11,12] the p53gene[13-18], the E-cadherin gene[19], and the c-mycgene[20].展开更多
To observe the relationship between tumor suppressor gene p16 expression and ovarian cancer occurrence and development. Metbods: Using ABC immunohistochemistry method, we investigated the expression of p16 in 72 cases...To observe the relationship between tumor suppressor gene p16 expression and ovarian cancer occurrence and development. Metbods: Using ABC immunohistochemistry method, we investigated the expression of p16 in 72 cases of ovarian neoplasm. Results: The positive rates of p16 in malignant, benign, borderline tumors and normal ovarian tissue were 7. 89%, 60.00%, 66. 67% and 83. 33%, respectively (P<0.01). In the cases whose tumors were more malignant and poorly differentiated, and who relapsed and died, the positive stainings were not discovered. Conclusiou: p16 is well related with the occurrence and development of malignant ovarian tumor.展开更多
AIM: To investigate loss of heterozygosity (LOH) of chromosome 9p21 and the prognostic relevance of p16 expression in gastrointestinal stromal tumor (GIST). METHODS: Fifty-one GIST patients (30 men and 21 women; media...AIM: To investigate loss of heterozygosity (LOH) of chromosome 9p21 and the prognostic relevance of p16 expression in gastrointestinal stromal tumor (GIST). METHODS: Fifty-one GIST patients (30 men and 21 women; median age 59 years; range 29-80 years) treated surgically within a 10-year period were grouped by aggressive behavior risk (17 with very low and low, 14 intermediate, and 20 high risk). GISTs were characterized immunohistochemically and evaluated for LOH of 9p21 by microsatellite analysis at D9S1751, D9S1846, D9S942, and D9S1748. LOH of 9p21 and immunohistochemicalexpression of p16 protein encoded at 9p21 were correlated with clinicopathological parameters, and the prognostic significance of p16 alterations was evaluated. RESULTS: Thirty-one (63.3%) cases showed LOH with at least one microsatellite marker. LOH frequency was 37.0% at D9S1751, 37.5% at D9S1846, 42.1% at D9S942, and 24.2% at D9S1748. There was a higher LOH frequency of D9S942 in high-risk than in non-highrisk tumors (P < 0.05, χ 2 = 4.47). Gender, age, tumor size and site were not correlated with allelic loss. Ninety percent (18/20) of the GIST patients in the high risk group showed LOH with at least one of the 9p21 markers, while 57.1% (8/14) in the intermediate risk group and 33.3% (5/15) in the very low and low risk groups, respectively (P < 0.05, χ 2 = 12.16). Eight (28.5%) of 31 patients with LOH and 1 (5.6%) of 18 patients without LOH died of the disease during the follow-up period. Loss of p16 protein expression occurred in 41.2%, but in 60% of the high risk group and 23.5% of the very low and low risk groups (P < 0.05, χ 2 = 4.98). p16 loss was associated with poor prognosis (P < 0.05, χ 2 = 4.18): the 3and 5-year overall survival rates were 84.8% and 70.8% for p16-negative and 100% and 92.0% for p16-positive patients, respectively. CONCLUSION: LOH at 9p21 appears to play an important role in GIST progression; decreased p16 expression in GIST is highly predictive of poor outcome.展开更多
Objective: To explore the changes and significance of tumor suppressor gene p53 in primary hepatocellu-lar carcinoma (PHC ) with hepatitis B virus (HBV ) infection. Methods: Tumor tissues and surrounding nontumortissu...Objective: To explore the changes and significance of tumor suppressor gene p53 in primary hepatocellu-lar carcinoma (PHC ) with hepatitis B virus (HBV ) infection. Methods: Tumor tissues and surrounding nontumortissues of sixteen PHC cases were studied by Southern hybridization to detect the state of HBV-DNA in tissues, byimmunohistochemical staining to determine HBsAg, HBxAg and p53 protein, and by PCR directed sequencing toanalyse the point mutation of p53 gene exons 5 to 8. Results: Among the 16 cases. 13 cases were HBV-DNA posi-tive, 10 tumor cases and 13 nontumor tissues cases HBxAg positive, and 9 cases posltive for p53 protein. The se-quencing of p53 gene point mutation was found in 5 cases, only one of which was sited at codon 249 G to T. Con-clusion: The mutation of p53 gene codon 249 is infrequent in HBV related PHC,indicating the accumulation of p53protein in cells may be associated with expression of HBxAg. HBxAg binding to p53 protein and inactivation of p53function play important roles in the development of PHC.展开更多
Objective:To investigate the relationship betweenp16INK4a and primary hepatocellular carcinoma (HCC),especially hepatitis B-related HCC. Methods: p16INK4a andits protein in HCC were analyzed with PCR-SSCP and theimmun...Objective:To investigate the relationship betweenp16INK4a and primary hepatocellular carcinoma (HCC),especially hepatitis B-related HCC. Methods: p16INK4a andits protein in HCC were analyzed with PCR-SSCP and theimmunohistochemistry methods respectively. Results: Thepositive incidence of p16INK4 protein expressing in HCC waslower than that of normal liver tissue (P<0.05), and theabsence of p16INK4 protein was associated with HCCmetastasis (P<0.05). The low frequency of mutation ofp16INK4 exonl and exon2 upstream fragment was found inHCC. Conclusion: Absence of p16INK4 protein in HCC wasnot associated with HBV-infection.展开更多
In this study, we infected human glioma U251 cells with a replication-defective recombinant adenovirus carrying the p16 gene. This adenovirus constructed was able to transfect exogenous p16 into the human glioma cells...In this study, we infected human glioma U251 cells with a replication-defective recombinant adenovirus carrying the p16 gene. This adenovirus constructed was able to transfect exogenous p16 into the human glioma cells efficiently, and direct a high level of p16 protein expression. Tumor-inhibition experiments demonstrated that treatment with the adenovirus-p16 significantly inhibited the growth of glioma cells in vitro as well as the in vivo development of tumors in nude mice bearing a brain glioma. The combination of adenovirus-p16 gene treatment and X-ray irradiation resulted in a greater inhibition of tumor growth. Adenovirus-mediated p16 gene therapy conferred a significant antitumor effect against human glioma cells both in vitro and in vivo, and that there was a synergistic effect when X-ray irradiation was also used.展开更多
Objective: This study was designed to investigate promoter methylation status and protein expression of p14^ARF gene in non-small cell lung cancer, and value the role of p14^ARF promoter methylation in carcinogenesis...Objective: This study was designed to investigate promoter methylation status and protein expression of p14^ARF gene in non-small cell lung cancer, and value the role of p14^ARF promoter methylation in carcinogenesis of non-small cell lung cancer. Methods: Promoter methylation status and protein expression of p14^ARF gene in 40 cases of non-small cell lung cancer were analyzed by methylation specific polymerase china reaction (MSP), restriction enzyme-related polymerase chain reaction (RE-PCR) and immunohistochemistry (IHC). Results: The positive rates of p14^ARF promoter methylation in tumor tissues and normal tissues adjacent to cancer were 17.5% (7/40) and 2.5% (1/40) respectively. There were statistically significant differences between them, P〈0.05. The results of RE-PCR were consistent with that of MSP. The expression rate of p14^ARF protein in tumor tissues was significantly lower than that in normal tissues adjacent to cancer, p〈0.01. Promoter methylation status and protein expression of p14^ARF gene in non-small cell lung cancer showed significantly an inverse correlation (r=-0.56, P〈0.01), and both of them did not relate statistically with the clinicopathologic characteristics of patients such as histological classification, clinical stage, differentiation grade and lymph node involvement. Conclusion: Promoter methylation is a crucial mechanism of inactivation of p14^ARF gene. Promoter methylation of p14^ARF gene might he involved in carcinogenesis of non-small cell lung cancer, and is an early event in development process of non-small cell lung cancer. It might be used as a new target in gene treatments in the future.展开更多
The tumor suppressor p63 is one of p53 family members and plays a vital role as a regulator of neuronal apoptosis in the development of the nervous system. However, the role of p63 in mature neuronal death has not bee...The tumor suppressor p63 is one of p53 family members and plays a vital role as a regulator of neuronal apoptosis in the development of the nervous system. However, the role of p63 in mature neuronal death has not been addressed yet. In this study, we first compared ischemia-induced effects on p63 expression in the hippocampal regions (CA1-3) between the young and adult gerbils subjected to 5 minutes of transient global cerebral ischemia. Neuronal death in the hippocampal CA1 region of young gerbils was significantly slow compared with that in the adult gerbils after transient global cerebral ischemia, p63 immunoreactivity in the hippocampal CA1 pyramidal neurons in the sham-operated young group was significantly low compared with that in the sham-operated adult group, p63 immunoreactivity was apparently changed in ischemic hippocampal CA1 pyramidal neurons in both ischemia-operated young and adult groups. In the ischemia-operated adult groups, p63 immunoreactivity in the hippocampal CA1 pyramidal neurons was significantly decreased at 4 days post-ischemia; however, p63 immunoreactivity in the ischemia-operated young group was significantly higher than that in the ischemia-operated adult group. At 7 days post-ischemia, p63 immunoreactivity was decreased in the hippocampal CA1 pyramidal neurons in both ischemia-operated young and adult groups. Change patterns of p63 level in the hippocampal CA1 region of adult and young gerbils after ischemic damage were similar to those observed in the immunohistochemical results. These findings indicate that higher and longer-term expression of p63 in the hippocampal CA1 region of the young gerbils after ischemia/reperfusion may be related to more delayed neuronal death compared to that in the adults.展开更多
Objective: To further refine the extent of deletion on chromosome 9p21-22 in nasopharyngeal carcinoma (NPC) and provide evidence for discovering new tumor suppressor gene. Methods: Loss of heterozygosity (LOH) on chro...Objective: To further refine the extent of deletion on chromosome 9p21-22 in nasopharyngeal carcinoma (NPC) and provide evidence for discovering new tumor suppressor gene. Methods: Loss of heterozygosity (LOH) on chromosome 9p21-22 was analyzed in 25 paired blood and tumor samples by using 11 high-density microsatellite polymorphic markers. Results: 17 of 25 cases (68.0%) showed LOH at one or more loci. Higher frequencies of LOH were found at four loci: D9S161 (35.0%), D9S1678 (31.5%), D9S263 (33.3%) and D9S1853 (33.3%), where 6 cases had a contiguous stretch of allelic loss. Conclusion: The minimal common region of deletion might be defined between D9S161 and D9S1853 (estimated about 2.7 cM in extent) at 9p21.1, suggesting that inactivation of one or more tumor suppressor genes located in this region may be an important step in NPC.展开更多
To explore the mechanism of interaction of hepatitis B virus (HBV) with P53 protein and its role in the hepatocarcinogenesis. Methods: HBV genome was analysed by computer program. The probe containing specific DNA-pro...To explore the mechanism of interaction of hepatitis B virus (HBV) with P53 protein and its role in the hepatocarcinogenesis. Methods: HBV genome was analysed by computer program. The probe containing specific DNA-protein binding site in HBV genome was synthesized and reacted with nuclei protein of hepatoma cell lines. Specific binding was determined by electrophoretic mobility shift assay, electrophoretic mobility supershift assay and in situ ultraviolet cross-linking assay. Co-transfection was performed by using reporter gene cat, p53 and dexamethasone inducible HBx to observe the biological functions of HBV binding to p53 protein. Results: A p53 response element binding sequence is present in HBV genome at upstream of enhancer I from 1047 to 1059 hp. This sequence is capable of binding to p53 protein and increasing accumulation of p53 protein in cells. Conclusion: The results strongly suggest that DNA-protein binding of HBV with P53 protein plays a significant role and it may be the predominant mechanism in the pathogenesis of HBV-associated hepatocellular carcinoma.展开更多
基金Project supported partly by the National Natural Science Foundation of China, No. 39870344
文摘INTRODUCTIONHepatocellular carcinoma (HCC) is one of the mostcommon human malignancies worldwide[1,2], and isclosely associated with infection of HBV and HCVand contamination of aflatoxin B1[3-6]. Althoughthe molecular mechanisms of hepatocarcinogenesisremain poorly understood, an increasing number ofgenetic abnormalities have been recognized[7-10],for example, the p16 gene[11,12] the p53gene[13-18], the E-cadherin gene[19], and the c-mycgene[20].
文摘To observe the relationship between tumor suppressor gene p16 expression and ovarian cancer occurrence and development. Metbods: Using ABC immunohistochemistry method, we investigated the expression of p16 in 72 cases of ovarian neoplasm. Results: The positive rates of p16 in malignant, benign, borderline tumors and normal ovarian tissue were 7. 89%, 60.00%, 66. 67% and 83. 33%, respectively (P<0.01). In the cases whose tumors were more malignant and poorly differentiated, and who relapsed and died, the positive stainings were not discovered. Conclusiou: p16 is well related with the occurrence and development of malignant ovarian tumor.
基金Supported by Key Discipline Project of Renji Hospital, Shang-hai Jiao Tong University School of Medicine, No. RJ4101304
文摘AIM: To investigate loss of heterozygosity (LOH) of chromosome 9p21 and the prognostic relevance of p16 expression in gastrointestinal stromal tumor (GIST). METHODS: Fifty-one GIST patients (30 men and 21 women; median age 59 years; range 29-80 years) treated surgically within a 10-year period were grouped by aggressive behavior risk (17 with very low and low, 14 intermediate, and 20 high risk). GISTs were characterized immunohistochemically and evaluated for LOH of 9p21 by microsatellite analysis at D9S1751, D9S1846, D9S942, and D9S1748. LOH of 9p21 and immunohistochemicalexpression of p16 protein encoded at 9p21 were correlated with clinicopathological parameters, and the prognostic significance of p16 alterations was evaluated. RESULTS: Thirty-one (63.3%) cases showed LOH with at least one microsatellite marker. LOH frequency was 37.0% at D9S1751, 37.5% at D9S1846, 42.1% at D9S942, and 24.2% at D9S1748. There was a higher LOH frequency of D9S942 in high-risk than in non-highrisk tumors (P < 0.05, χ 2 = 4.47). Gender, age, tumor size and site were not correlated with allelic loss. Ninety percent (18/20) of the GIST patients in the high risk group showed LOH with at least one of the 9p21 markers, while 57.1% (8/14) in the intermediate risk group and 33.3% (5/15) in the very low and low risk groups, respectively (P < 0.05, χ 2 = 12.16). Eight (28.5%) of 31 patients with LOH and 1 (5.6%) of 18 patients without LOH died of the disease during the follow-up period. Loss of p16 protein expression occurred in 41.2%, but in 60% of the high risk group and 23.5% of the very low and low risk groups (P < 0.05, χ 2 = 4.98). p16 loss was associated with poor prognosis (P < 0.05, χ 2 = 4.18): the 3and 5-year overall survival rates were 84.8% and 70.8% for p16-negative and 100% and 92.0% for p16-positive patients, respectively. CONCLUSION: LOH at 9p21 appears to play an important role in GIST progression; decreased p16 expression in GIST is highly predictive of poor outcome.
文摘Objective: To explore the changes and significance of tumor suppressor gene p53 in primary hepatocellu-lar carcinoma (PHC ) with hepatitis B virus (HBV ) infection. Methods: Tumor tissues and surrounding nontumortissues of sixteen PHC cases were studied by Southern hybridization to detect the state of HBV-DNA in tissues, byimmunohistochemical staining to determine HBsAg, HBxAg and p53 protein, and by PCR directed sequencing toanalyse the point mutation of p53 gene exons 5 to 8. Results: Among the 16 cases. 13 cases were HBV-DNA posi-tive, 10 tumor cases and 13 nontumor tissues cases HBxAg positive, and 9 cases posltive for p53 protein. The se-quencing of p53 gene point mutation was found in 5 cases, only one of which was sited at codon 249 G to T. Con-clusion: The mutation of p53 gene codon 249 is infrequent in HBV related PHC,indicating the accumulation of p53protein in cells may be associated with expression of HBxAg. HBxAg binding to p53 protein and inactivation of p53function play important roles in the development of PHC.
文摘Objective:To investigate the relationship betweenp16INK4a and primary hepatocellular carcinoma (HCC),especially hepatitis B-related HCC. Methods: p16INK4a andits protein in HCC were analyzed with PCR-SSCP and theimmunohistochemistry methods respectively. Results: Thepositive incidence of p16INK4 protein expressing in HCC waslower than that of normal liver tissue (P<0.05), and theabsence of p16INK4 protein was associated with HCCmetastasis (P<0.05). The low frequency of mutation ofp16INK4 exonl and exon2 upstream fragment was found inHCC. Conclusion: Absence of p16INK4 protein in HCC wasnot associated with HBV-infection.
基金Science and Technology Fund Program of Shaanxi Province, No. 2002K10-G3Xi'an Jiaotong University Innovation Fund, No. 0203207
文摘In this study, we infected human glioma U251 cells with a replication-defective recombinant adenovirus carrying the p16 gene. This adenovirus constructed was able to transfect exogenous p16 into the human glioma cells efficiently, and direct a high level of p16 protein expression. Tumor-inhibition experiments demonstrated that treatment with the adenovirus-p16 significantly inhibited the growth of glioma cells in vitro as well as the in vivo development of tumors in nude mice bearing a brain glioma. The combination of adenovirus-p16 gene treatment and X-ray irradiation resulted in a greater inhibition of tumor growth. Adenovirus-mediated p16 gene therapy conferred a significant antitumor effect against human glioma cells both in vitro and in vivo, and that there was a synergistic effect when X-ray irradiation was also used.
文摘Objective: This study was designed to investigate promoter methylation status and protein expression of p14^ARF gene in non-small cell lung cancer, and value the role of p14^ARF promoter methylation in carcinogenesis of non-small cell lung cancer. Methods: Promoter methylation status and protein expression of p14^ARF gene in 40 cases of non-small cell lung cancer were analyzed by methylation specific polymerase china reaction (MSP), restriction enzyme-related polymerase chain reaction (RE-PCR) and immunohistochemistry (IHC). Results: The positive rates of p14^ARF promoter methylation in tumor tissues and normal tissues adjacent to cancer were 17.5% (7/40) and 2.5% (1/40) respectively. There were statistically significant differences between them, P〈0.05. The results of RE-PCR were consistent with that of MSP. The expression rate of p14^ARF protein in tumor tissues was significantly lower than that in normal tissues adjacent to cancer, p〈0.01. Promoter methylation status and protein expression of p14^ARF gene in non-small cell lung cancer showed significantly an inverse correlation (r=-0.56, P〈0.01), and both of them did not relate statistically with the clinicopathologic characteristics of patients such as histological classification, clinical stage, differentiation grade and lymph node involvement. Conclusion: Promoter methylation is a crucial mechanism of inactivation of p14^ARF gene. Promoter methylation of p14^ARF gene might he involved in carcinogenesis of non-small cell lung cancer, and is an early event in development process of non-small cell lung cancer. It might be used as a new target in gene treatments in the future.
基金supported by 2013 Research Grant from Kangwon National University(120131480)Basic Science Research Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Education(NRF-2014R1A6A3A01056005)
文摘The tumor suppressor p63 is one of p53 family members and plays a vital role as a regulator of neuronal apoptosis in the development of the nervous system. However, the role of p63 in mature neuronal death has not been addressed yet. In this study, we first compared ischemia-induced effects on p63 expression in the hippocampal regions (CA1-3) between the young and adult gerbils subjected to 5 minutes of transient global cerebral ischemia. Neuronal death in the hippocampal CA1 region of young gerbils was significantly slow compared with that in the adult gerbils after transient global cerebral ischemia, p63 immunoreactivity in the hippocampal CA1 pyramidal neurons in the sham-operated young group was significantly low compared with that in the sham-operated adult group, p63 immunoreactivity was apparently changed in ischemic hippocampal CA1 pyramidal neurons in both ischemia-operated young and adult groups. In the ischemia-operated adult groups, p63 immunoreactivity in the hippocampal CA1 pyramidal neurons was significantly decreased at 4 days post-ischemia; however, p63 immunoreactivity in the ischemia-operated young group was significantly higher than that in the ischemia-operated adult group. At 7 days post-ischemia, p63 immunoreactivity was decreased in the hippocampal CA1 pyramidal neurons in both ischemia-operated young and adult groups. Change patterns of p63 level in the hippocampal CA1 region of adult and young gerbils after ischemic damage were similar to those observed in the immunohistochemical results. These findings indicate that higher and longer-term expression of p63 in the hippocampal CA1 region of the young gerbils after ischemia/reperfusion may be related to more delayed neuronal death compared to that in the adults.
基金a grant from the National "863" Project of China (No. 102-10-01-05).
文摘Objective: To further refine the extent of deletion on chromosome 9p21-22 in nasopharyngeal carcinoma (NPC) and provide evidence for discovering new tumor suppressor gene. Methods: Loss of heterozygosity (LOH) on chromosome 9p21-22 was analyzed in 25 paired blood and tumor samples by using 11 high-density microsatellite polymorphic markers. Results: 17 of 25 cases (68.0%) showed LOH at one or more loci. Higher frequencies of LOH were found at four loci: D9S161 (35.0%), D9S1678 (31.5%), D9S263 (33.3%) and D9S1853 (33.3%), where 6 cases had a contiguous stretch of allelic loss. Conclusion: The minimal common region of deletion might be defined between D9S161 and D9S1853 (estimated about 2.7 cM in extent) at 9p21.1, suggesting that inactivation of one or more tumor suppressor genes located in this region may be an important step in NPC.
文摘To explore the mechanism of interaction of hepatitis B virus (HBV) with P53 protein and its role in the hepatocarcinogenesis. Methods: HBV genome was analysed by computer program. The probe containing specific DNA-protein binding site in HBV genome was synthesized and reacted with nuclei protein of hepatoma cell lines. Specific binding was determined by electrophoretic mobility shift assay, electrophoretic mobility supershift assay and in situ ultraviolet cross-linking assay. Co-transfection was performed by using reporter gene cat, p53 and dexamethasone inducible HBx to observe the biological functions of HBV binding to p53 protein. Results: A p53 response element binding sequence is present in HBV genome at upstream of enhancer I from 1047 to 1059 hp. This sequence is capable of binding to p53 protein and increasing accumulation of p53 protein in cells. Conclusion: The results strongly suggest that DNA-protein binding of HBV with P53 protein plays a significant role and it may be the predominant mechanism in the pathogenesis of HBV-associated hepatocellular carcinoma.