Analysis of Newly Identified and Rare Synonymous Genetic Variants in the RET Gene in Patients with Medullary Thyroid Carcinoma in Polish Population.

Gain-of-function germline mutations of the RET proto-oncogene are responsible for initiation of carcinogenesis within the thyroid gland and development of hereditary form of medullary thyroid carcinoma and MEN2 syndrome. Genotype-phenotype correlations are established for most RET mutations, but the importance of the synonymous changes in this gene remains debatable. We aimed to analyze RET gene variants in Polish population.

PIK3CA mutations and amplification in endometrioid endometrial carcinomas: relation to other genetic defects and clinicopathologic status of the tumors.

Alterations of the PIK3CA gene occur in endometrial carcinomas, but their role in the carcinogenesis of those malignancies is still poorly understood. In this study, PIK3CA mutations and amplification in 196 endometrioid endometrial carcinomas and 20 endometrial hyperplasias were assessed by single-strand conformation polymorphism (PCR-SSCP), sequencing, and quantitative polymerase chain reaction. Results were correlated with mutations in the PTEN, KRAS, and CTNNB1 genes and with the clinicopathologic parameters of the tumors.

TP53 mutations in endometrial cancers: relation to PTEN gene defects.

Objective: The PTEN and TP53 genes participate in the carcinogenesis of many malignancies, but the role of both genes in endometrial carcinogenesis is not fully elucidated. The aim of the study was to determine the quality and the frequency of incidence of TP53 and PTEN gene mutations and to assess their coexistence in endometrial cancers. Besides that, the correlation was studied between the detected defects and clinicohistopathological characteristics of the studied endometrial cancers.

Molecular genetic defects in endometrial carcinomas: microsatellite instability, PTEN and beta-catenin (CTNNB1) genes mutations.

Purpose: The present study aims to assess the incidence of microsatellite instability (MSI) and mutations in the PTEN and beta-catenin (CTNNB1) genes in endometrial carcinomas and to analyze the detected defects in these factors in relation to each other and to the clinico-pathological features of tumors.

Materials And Methods: In a series of 56 endometrioid endometrial carcinomas, the status of MSI was determined using nine polymorphic markers, and mutations in all exons of the PTEN gene and in exon 3 of the CTNNB1 gene were evaluated by SSCP and sequencing methods.

Results: Microsatellite instability was found in 18 carcinomas (32.

Preliminary studies on DNA retardation by MutS applied to the detection of point mutations in clinical samples.

MutS ability to bind DNA mismatches was applied to the detection of point mutations in PCR products. MutS recognized mismatches from single up to five nucleotides and retarded the electrophoretic migration of mismatched DNA. The electrophoretic detection of insertions/deletions above three nucleotides is also possible without MutS, thanks to the DNA mobility shift caused by the presence of large insertion/deletion loops in the heteroduplex DNA.

The coexistence of ERBB2, INT2, and CMYC oncogene amplifications and PTEN gene mutations in endometrial carcinoma.

Purpose: To evaluate the frequency of ERBB2, INT2 and CMYC oncogene amplifications and their coexistence with PTEN gene mutations in endometrial carcinomas.

Methods: In 54 endometrial carcinomas amplification of ERBB2, INT2 and CMYC was determined using differential polymerase chain reaction (dPCR), and mutations in all exons of PTEN were investigated by PCR-SSCP and direct sequencing methods. Results were correlated with clinicopathological features of tumors.

Assessment of the quality and frequency of mutations occurrence in PTEN gene in endometrial carcinomas and hyperplasias.

The quality and frequency of mutations in PTEN gene were assessed in 59 carcinomas and 6 hyperplasias of the endometrium in women. Screening for mutations was done in all exons of PTEN gene by the PCR-SSCP analysis and DNA sequencing. Results were correlated with histological status and clinical features of endometrial carcinomas.