Correlation of PTEN Mutations with Microsatellite Instability in Endometrial Carcinoma / 中国医科大学学报

Objective To assess the prevalence and clinicopathologic significance of the microsatellite instability(MSI),PTEN mutations and their correlations in endometrial carcinogenesis.Methods The MSI analysis was performed using five microsatellite markers in paired uterine endometrial carcinoma(UEC) and atypical endometrial hyperplasia(AH).PTEN mutations were detected by single-strand conformation polymorphism(FCR-SSCP) analysis and DNA sequencing in UEC,AH and normal epithelium(NE).Rescults There was a significant difference in the incidence of PTEN mutations among AH,UEC and NE(P<0.01).PTEN mutations changed significantly in AH-the direct precursor to UEC(P<0.01).PTEN mutations correlated significantly with the clinical stage of the UEC(P<0.05).In UEC with MSI,PTEN mutations were detected in the short coding mononucleotide repeats(A) in 2(18.2%) of the 11 carcinomas.PTEN had a substantially higher frequency of mutations in UEC with MSI compared with the frequency of mutations in UEC without MSI(P<0.05).Conclusion PTEN mutations and MSI were two of the most common genetic alterations and correlated with each other in uterine endometrioid carcinoma.PTEN mutations might be secondary to deficiencies in mismatch repair and give some explanation for the frequent presence of PTEN mutations in MSI positive UEC.

Study on the loss of heterozygosity of microsatellite DNA on chromosome 6 in human T-cell lymphoma / 肿瘤

Objective: To study the loss of heterozygosity (LOH) at 6 markers of microsatellite polymorphism on the chromosome 6 in T-cell lymphoma (TCL) to determine whether there existed tumor suppressor genes in the area related with the initiation and development of TCL. Methods: Six microsatellite polymorphism markers (D6S251, D6S275, D6S287, D6S267, D6S262, and D6S264) on the chromosome 6 were selected. We performed the amplification of microsatellite DNA with PCR, polyacrylamide gel electrophoresis and silver staining to detect LOH in 42 cases of T-cell lymphoma and the corresponding normal tissues. Results: LOH were detected at more than one locus in 13 out of 42 TCL patients (30.95%). Among the 6 loci, LOH occurred more frequently at D6S262 (10.3%), D6S287 (10.0%), and D6S267 (7.3%). No significant difference was found in LOH incidence between different clinicopathologic classifications (P > 0.05). Conclusion: The LOHs occur more frequently at markers D6S262, D6S287, and D6S267 on the chromosome 6q21 to 6q23. Cyclin C gene localized to chromosome 6q21 may be the candidate of tumor suppressor gene related with initiation and progression of TCL. Chromosome 6q21-6q23 may harbor a tumor suppressor locus which was related with TCL.

Study of microsatellite instability in epithelial ovarian tumors / 北京大学学报(医学版)

Objective: To evaluate the frequency of MSI in epithelial ovarian tumors and its relationship with clinicopathologic features. Methods: Ninety fresh specimens of epithelial ovarian tumors, including 74 primary and 16 secondary tumors, were collected. Microsatellite analysis was carried out using 5 mono- and dinucleotide markers from the National Cancer Institute Consensus Panel by fluorescence-labeled polymerase chain reaction. Results: Of 90 epithelial ovarian tumors analyzed, 18 demonstrated a high level of microsatellite instability (MSI-H), 30 demonstrated a low level of microsatellite instability (MSI-L), and the remaining 42 exhibited microsatellite stability (MSS). Frequency of microsatellite instability (MSI) at loci BAT-25 was higher than that at any other loci. No correlation was found between MSI level and patient age, tumor type, tumor differentiation (P>0.05). But the microsatellite instability-high phenotype correlates with clinical stage.It tended to occur more frequently in early-stage tumors (P=0.03). Conclusion: The frequent MSI in epithelial ovarian tumors suggests that it is an early event to involve in the development of epithelial ovarian tumors.

Gene-based individual identification of hardly recognizable victims in an accident / 解放军医学杂志

Objective To identify hardly recognizable victims of an accident. Methods Tissues of muscle and cartilage were obtained from the dead bodies. Some of the tissues were checked by routine pathological microscopy. Genomic DNA was isolated from the tissues and subjected to STR profiling of 16 sites via multiple fluorescent PCR analysis with ABI’s AmpFLSTR Amplification Kit. Individual identification of the victims was carries out by matching the STR profiles of the victims with those of the parents. Results Routine pathological microscopy showed that the structure of some of the muscle tissues was totally destroyed, while the structure of all cartilage tissues was basically intact. Three patterns of genomic DNA isolated from victims’ muscle tissues could be seen in gel electrophoresis, i.e. basically undegraded, partially degraded and totally degraded. STR profiling failed due to the degradation of genomic DNA of some of the muscle tissues, while all samples of the cartilage genomic DNA could be used for STR typing. Conclusion Paternity identification based on STR genotyping was an effective way to identify victims of accidents, and cartilage tissue from the victims was the first choice for that purpose.

Analysis of genetic instability of chromosome 19, 20, 21, 22 and X in retinoblastoma / 中华眼底病杂志

Objective To explore the presence of common genetic alterations in retinoblastoma and to localize the altered genomic regions. Methods Genetic instability of chromosome 19, 20, 21, 22 and X of 15 microdissected retinoblastoma tumors were analyzed by the loss of heterozygosity (LOH) and microsatellite instability (MSI). Results Among the 15 patients with retinoblastoma, genome instability [LOH and(or) MSI] at one or more loci on the 5 chromosomes in 10 (67%), in which the loss of a single allele was more frequent in chromosomes 19 (33%) and 20 (27%) than in the other 3 chromosomes. High-frequency LOH between D19S902 and D19S571 suggested gene loci in the 19q13 region might be associated with tumor development in retina. According to the result of MSI, MSI occured at least in one subset of retinoblastoma. Conclusions Our results provide first evidence of LOH in chromosomes 19 and 20 in retinoblastoma and further support the presence of genome instability in retinoblastoma that may play an important role in the tumorigenesis or progression of retinoblastoma.

Validation of multiplex microsatellite DNA amplification system for use in monitoring umbilical cord blood cell transplantation / 中华器官移植杂志

Objective To study the validation of fluorescent multiplex microsatellite amplification technique for use in the caseworks of umbilical blood cell transplantation monitor. Methods Six post-transplant recipients of umbilical cord blood cell transplantation were monitored by analyzing microsatellite DNA loci. DNA samples were amplified using a fluorescent labeling primers multiplex amplification system of 15 microsatellites markers, followed by typing on a DNA automated sequencer. Recipients' or donors' microsatellites DNA profiles were compared before and after transplantation. Results All recipients and donors exhibited different DNA profiles. Without reference samples of pre-transplant or donors, the changes of the 15 microsetellites genotypes of the post-transplant recipients still could be analyzed. The recipient type turned to donor type was observed over time. Conclusion Under the condition of using multiplex amplification of the 15 microsatellites to monitor the umbilical blood cell transplantation, reference sample of pre-transplant or donor did not need to be detected simultaneously.

Detection of Microsatellite Instability in Lesions from Patients with Coal Arsenic Poisoning / 中华皮肤科杂志

0.05). Conclusions MSI and LOH may play a certain role in the carcinogenesis and progression of arsenic-induced skin lesions.

The microsatellite instability and loss of heterozygosity in head and neck squamous cell carcinomas / 中国病理生理杂志

AIM: To examine the microsatellite instability (MSI) and loss of heterozygosity (LOH) in head and neck squamous cell carcinomas (HNSCC). METHODS: 36 cases of HNSCC were analyzed with 15 microsatellite markers from chromosome 3,5,6,8,9,13,17 and 18. RESULTS: Among the 36 cases of HNSCC, 27.8%(10/36)of samples showed MSI in one to eight microsatellite markers. High frequent MSI occurred at D17S520(22.9%), D6S105(16 7%)and D8S264(13 9%). LOH was detected on the site of 9p21-p22 and 3p14. No correlations were found between allelic instability and grade or stage of the tumor. CONCLUSION: Our data suggest that MSI is a common genetic change in HNSCC. Tumor suppressor genes related to HNSCC may harbor at chromosome 9p21-p22 and 3p14 regions. [