AIM： To investigate the effect of pituitary homeobox 1 （PITX1） expression in cases of human gastric cancer on cancer differentiation and progression, and carcinogenesis. METHODS： Using polyclonal PITX1 antibodies,...AIM： To investigate the effect of pituitary homeobox 1 （PITX1） expression in cases of human gastric cancer on cancer differentiation and progression, and carcinogenesis. METHODS： Using polyclonal PITX1 antibodies, we studied the expression of PITX1 in normal gastric mucosa, atypical hyperplasia, intestinal metaplasia, and cancer tissue samples from 83 gastric cancer patients by immunohistochemistry. Moreover, semi-reverse transcription polymerase chain reaction （semi-RT-PCR） was performed to detect the mRNA level of PITX1 in three gastric cancer cell lines and a normal gastric epithelial cell line. Subsequently, somatic mutations of the PITX1 gene in 71 gastric cancer patients were analyzed by a combination of denaturing high performance liquid chromatography （DHPLC） and DNA sequencing. RESULTS： Immunohistochemistry showed that PITXl was strongly or moderately expressed in the parietal cells of normal gastric mucosa （100%）, while 55 （66.3%） out of 83 samples of gastric cancers showed decreased PITXl expression. Moreover, PITXl expression was reduced in 20 out of 28 cases （71.5%） of intestinal metaplasia, but in only 1 out of 9 cases （11%） of atypical hyperplasia. More importantly, PITXl expression was significantly associated with the differentiation, position and invasion depth of gastric cancers （r = -0.316, P 〈 0.01; r = 0.213, P 〈 0.05; r = -0.259, P 〈 0.05, respectively）. Similarly, levels of PITXl mRNA were significantly decreased in 2 gastric cancer cell lines, BGC-823 and SGC-7901, compared with the normal gastric epithelial cell line GES-1 （0.306 ± 0.060 vs 0.722 ± 0.102, P 〈 0.05; 0.356 ± 0.081 vs 0.722 ± 0.102, P 〈 0.05, respectively）. Nevertheless, no somatic mutation of PITX1 gene was found in 71 samples of gastric cancer by DHPLC analysis followed by sequencing. CONCLUSION： Down-regulation of PITX1 may be a frequent molecular event in gastric carcinogenesis. Aberrant levels of PITXl expression may be closely correlated with the progression and differentiation of gastric cancer,展开更多
Ovarian cancer is a major health problem for women in the United States. Despite evidence of considerable heterogeneity, most cases of ovarian cancer are treated in a similar fashion. The molecular basis for the clini...Ovarian cancer is a major health problem for women in the United States. Despite evidence of considerable heterogeneity, most cases of ovarian cancer are treated in a similar fashion. The molecular basis for the clinicopathologic characteristics of these tumors remains poorly defined. Whole genome expression profiling is a genomic tool, which can identify dysregulated genes and uncover unique sub-classes of tumors. The application of this technology to ovarian cancer has provided a solid molecular basis for differences in histology and grade of ovarian tumors. Differentially expressed genes identified pathways implicated in cell proliferation, invasion, motility, chromosomal instability, and gene silencing and provided new insights into the origin and potential treatment of these cancers. The added knowledge provided by global gene expression profiling should allow for a more rational treatment of ovarian cancers. These techniques are leading to a paradigm shift from empirical treatment to an individually tailored approach. This review summarizes the new genomic data on epithelial ovarian cancers of different histology and grade and the impact it will have on our understanding and treatment of this disease.展开更多
The short report will be focused on the genetic basis and possible mechanisms of tumorigenesis, common types of cancer, the importance of genetic diagnosis of cancer, and the methodology of cancer genetic diagnosis. T...The short report will be focused on the genetic basis and possible mechanisms of tumorigenesis, common types of cancer, the importance of genetic diagnosis of cancer, and the methodology of cancer genetic diagnosis. They will also review presymptomatic testing of hereditary cancers, and the application of expression profiling to identify patients likely to benefit from particular therapeutic approaches.展开更多
基金The National Science Fund for Distinguished Young Scholars, No. 30125017The Major State Basic Research Development Program of China (973 Program), No. 2002CB513100
文摘AIM： To investigate the effect of pituitary homeobox 1 （PITX1） expression in cases of human gastric cancer on cancer differentiation and progression, and carcinogenesis. METHODS： Using polyclonal PITX1 antibodies, we studied the expression of PITX1 in normal gastric mucosa, atypical hyperplasia, intestinal metaplasia, and cancer tissue samples from 83 gastric cancer patients by immunohistochemistry. Moreover, semi-reverse transcription polymerase chain reaction （semi-RT-PCR） was performed to detect the mRNA level of PITX1 in three gastric cancer cell lines and a normal gastric epithelial cell line. Subsequently, somatic mutations of the PITX1 gene in 71 gastric cancer patients were analyzed by a combination of denaturing high performance liquid chromatography （DHPLC） and DNA sequencing. RESULTS： Immunohistochemistry showed that PITXl was strongly or moderately expressed in the parietal cells of normal gastric mucosa （100%）, while 55 （66.3%） out of 83 samples of gastric cancers showed decreased PITXl expression. Moreover, PITXl expression was reduced in 20 out of 28 cases （71.5%） of intestinal metaplasia, but in only 1 out of 9 cases （11%） of atypical hyperplasia. More importantly, PITXl expression was significantly associated with the differentiation, position and invasion depth of gastric cancers （r = -0.316, P 〈 0.01; r = 0.213, P 〈 0.05; r = -0.259, P 〈 0.05, respectively）. Similarly, levels of PITXl mRNA were significantly decreased in 2 gastric cancer cell lines, BGC-823 and SGC-7901, compared with the normal gastric epithelial cell line GES-1 （0.306 ± 0.060 vs 0.722 ± 0.102, P 〈 0.05; 0.356 ± 0.081 vs 0.722 ± 0.102, P 〈 0.05, respectively）. Nevertheless, no somatic mutation of PITX1 gene was found in 71 samples of gastric cancer by DHPLC analysis followed by sequencing. CONCLUSION： Down-regulation of PITX1 may be a frequent molecular event in gastric carcinogenesis. Aberrant levels of PITXl expression may be closely correlated with the progression and differentiation of gastric cancer,
文摘Ovarian cancer is a major health problem for women in the United States. Despite evidence of considerable heterogeneity, most cases of ovarian cancer are treated in a similar fashion. The molecular basis for the clinicopathologic characteristics of these tumors remains poorly defined. Whole genome expression profiling is a genomic tool, which can identify dysregulated genes and uncover unique sub-classes of tumors. The application of this technology to ovarian cancer has provided a solid molecular basis for differences in histology and grade of ovarian tumors. Differentially expressed genes identified pathways implicated in cell proliferation, invasion, motility, chromosomal instability, and gene silencing and provided new insights into the origin and potential treatment of these cancers. The added knowledge provided by global gene expression profiling should allow for a more rational treatment of ovarian cancers. These techniques are leading to a paradigm shift from empirical treatment to an individually tailored approach. This review summarizes the new genomic data on epithelial ovarian cancers of different histology and grade and the impact it will have on our understanding and treatment of this disease.
文摘The short report will be focused on the genetic basis and possible mechanisms of tumorigenesis, common types of cancer, the importance of genetic diagnosis of cancer, and the methodology of cancer genetic diagnosis. They will also review presymptomatic testing of hereditary cancers, and the application of expression profiling to identify patients likely to benefit from particular therapeutic approaches.
