Objective To identify and isolate the variant gene associated with gastric adenocarcinoma and clone the fragment of variant gene.Methods By arbitrarily primer polymerase chain reaction (AP-PCR), DNA samples from 5 matched gastric adenocarcinoma and non-tumor gastric tissues were analysed. Results The produced AP-PCR profiles were different in each matched gastric adenocarcinoma and non-tumor gastric tissue. One differentiated amplified DNA fragments PW2.2 from a matched gastric adenocarcinoma were cloned. The result of Southern blot hybridization with PW2.2 as a probe showing that this fragment was also found in some other gastric adenocarcinoma samples. Conclusion AP-PCR fingerprinting assay can be used to identify and clone the variant genes associated with gastric adenocarcinoma.
Objective To evaluate the potential of specific mRNA marker keratin 19(K19) to detect micrometastasis by reverse transcriptase polymerase chain reaction (RT-PCR) .Methods One hundred and ninty four regional lymph nodes harvested from 6 cases of benign diseases, 4 cases of breast carcinoma, 5 cases of gastric carcinoma and 12 cases of colorectal carcinoma patients were examined by conventional pathology and amplifying tissue specific K19 mRNA by RT-PCR separately, then the two methods were compared with each other. Results None of the 34 lymph nodes which were pathological metastasis-negative from benign diseases expressed K19 mRNA by RT-PCR, all of the 28 regional lymph nodes which were pathological metastasis-positive from malignant cases showed trains of K19 mRNA by RT-PCR. Of the 132 lymph nodes which were pathological metastasis-negative from malignant cases, 11 lymph nodes were detected with micrometastasis by genetic diagnosis.Conclusion Genetic diagnosis of lymph node micrometastasis is more sensitive than conventional pathology and has diagnostic value and merits further study.
ObjectiveTo evaluate the possible role of the expression of insulin-like growth factor-1 receptor (IGF-1R) in determining rectal cancer radiosensitivity. MethodsThe paired preradiation biopsy specimens and postoperative specimens were obtained from 87 patients with rectal cancer in the department of digestive tumor surgery, Jiangsu Province Hospital of Traditional Chinese Medicine, Affiliated Hospital of Nanjing University of Traditional Chinese Medicine from January 2009 to December 2010. The IGF-1R expression was examined by immunohistochemistry (IHC) and reverse transcription-polymerase chain reaction (RT-PCR). The tumor radiosensitivity was defined according to Rectal Cancer Regression Grade, then the relation between the IGF-1R expression and tumor radiosensitivity was evaluated. ResultsCompared with the preradiation biopsy specimens, IGF-1R expression significantly increased in the paired postoperative specimens of the residual cancer cells (Plt;0.001). The IHC result demonstrated IGF-1R overexpression was significantly associated with a poor response to radiotherapy (rs=0.401, Plt;0.001); RT-PCR detection of IGF-1R expression on preradiation biopsy specimens also showed that IGF-1R mRNA negative patients had a higher radiation sensitivity (rs=0.497, Plt;0.001). ConclusionDetection of IGF-1R expression may predict radiosensitivity of preoperative irradiation for rectal cancer.
Purpose To investigate the relationship between mitochondrial DNA 11778 mutation and clinical characteristics of patients with Laber is hereditary optic neuropathy(LHON). Methods PCR RFLPs (MaeⅢ) and mutation specific primer PCR(MSP-PCR) were used simultaneously to detect mitochondrial DNA 11778 mutation. Results Among 10 subjects who habored 11778 mutation,one was a carrier and nine were patients with LHON.Of the nine patients,six were males and three were females.The age of onset ranged from 12 to 25 years old and the onset interval of the two eyed varied between 0 to 6 months. The visual acuity was CF/10cm-0.1 except one who lost her vision after delivery but recovered gradually.The results of visual field,VEP and color vision were abnormal but ERG and systemic status were all normal. Conclusion Molecular biological detection of the ten subjects showed that they all habored mtDNA 11778 mutation.The existence of carrier and visual recovery imlied that mtDNA mutation was a primary cause of LHON,but other factors such as endocrine disorder might influence the pathogenesis of LHON. (Chin J Ocul Fundus Dis,1998,14:156-158)
【 Abstract 】 Objective To study the mRNA expression of BC047440 gene in multiplicate malignant tumor tissues and the corresponding adjacent tissues, and to investigate its roles in the carcinogenesis and development of malignant tumors. Methods Forty-eight cases of malignant tumor tissues and their adjacent non-cancerous tissues were examined. The mRNA expression of BC047440 gene in those tissues of liver cancer, cholangiocarcinoma, gastric cancer, carcinoma of large intestine, glioma, and breast cancer were measured by semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR). Results ① The mRNA expressions of BC047440 gene in liver cancer, gastric cancer, cholangiocarcinoma and carcinoma of large intestine were significantly higher than those in their adjacent non-cancerous tissues (Plt;0.05 or 0.01). BC047440 gene were highly expressed in both glioma and its adjacent tissues (Pgt;0.05), and poorly expressed in both breast cancer and its adjacent tissues (Pgt;0.05). ② There were close relationships between BC047440 gene expression and clinicopathologic findings of liver cancer, including tumor size and portal vein invasion (Plt;0.05). ③ There were also close relationships between BC047440 gene expression and different clinical stages in alimentary canal cancers (Plt;0.05). Conclusion The over expression of BC047440 gene may be related with the growth, infiltration and metastasis of some malignant tumors, including liver cancer, cholangiocarcinoma, gastric cancer, carcinoma of large intestine and glioma.
ObjectiveTo explore the clinical significance of promoter hypermethylation of O6-methylguanine-DNA methyltransferase (MGMT) in cholangiocarcinoma. MethodsPromoter methylation status of MGMT gene and expression of MGMT protein were detected in cholangiocarcinoma by methylationspecific PCR and immunohistochemical staining, respectively. ResultsAberrant methylation of MGMT gene was detected in 17 patients (47.2%). Twentyone cases showed negative immunoreactivities. Of 21 patients with negative MGMT expression, 14 patients had aberrant methylation of MGMT gene. In 15 patients with positive MGMT expression, aberrant methylation of MGMT gene was only found in three cases. There was a negative correlation between promoter methylation status of MGMT gene and the expression of MGMT protein (rs=-0.816, Plt;0.05). Promoter methylation status of MGMT gene was related to depth of invasion, degree of differentiation, and TNM stage (Plt;0.05), but not to age of patient, gender, pathological type, and lymph node metastasis (Pgt;0.05). ConclusionsHypermethylation of MGMT promoter is a frequency molecular event in cholangiocarcinoma and may be involved in carcinogenesis. Methylation status of MGMT gene may be used to evaluate malignant degree of cholangiocarcinoma.