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R F Gar'kavtseva

Publications and source records attributed to R F Gar'kavtseva.

At least 19 recordsLinked to original sources

[Population genetic analysis of the association between the BRCA1 and P53 gene polymorphisms and the risk of sporadic breast cancer].

Polymorphism of two tumor-suppressor genes, BRCA1 and P53, was examined. DNA was extracted from blood leukocytes of the women affected with breast cancer (N = 151) and of the women with no clinical symptoms of tumor diseases (N = 191). Typing of the polymorphic variants was performed using PCR-RFLP method. It was demonstrated that the genetic structure of the patient group (taking into consideration BRCA1 and P53 polymorphic variants) differed from that of the control group. The group of genotypes, found exclusively among the patients, as well as the group of "resistant" genotypes revealed predominantly among the controls, was described. Detection of the genotype A1A1 B1B1 S1S1 C1C1 F1F1 J2J2, whose frequency in control group was eight times higher than in the patient group, was an additional confirmation of the existence of "resistant" genotypes. These findings point to the association between the combinations of the BRCA1 and P53 allelic variants and the risk of breast cancer.

Alleles↗

[Identification of the hereditary variants of skin melanoma].

The identification of hereditary variants of cutaneous melanoma and analysis of the role of hereditary factors and syndromes predisposing to cutaneous melanoma were carried out. The involvement of individual nevus phenotypes in the development of this disease was determined. Based on a survey of recent molecular biological data and our studies, the etiological and genetic heterogeneity of cutaneous melanoma is reported. In relatives of patients with cutaneous melanoma and persons with multiple pigmented nevi, the malignant tumors proved to be differentiated in the direction of the neural crist tissues and/or derivatives of cutaneous mesenchyma. Based on the evidence obtained, the approaches have been developed to formation of risk groups for the purpose of early diagnostics of cutaneous melanoma.

Diagnosis, Differential↗

Spectrum of mutations in BRCA1 gene in hereditary forms of breast and ovarian cancer in Russian families.

The 5382insC mutation predominated (94%) in the spectrum of detected mutations of BRCA1 gene. High incidence of this mutation in familial breast cancer detected for the first time attested to origination of 5382insC mutation from the European part of Russia. The percentage of families with mutations in BRCA1 gene and familial predisposition to ovarian cancer was significantly higher than in hereditary predisposition to breast cancer (p<0.007). These data suggest that clinical manifestation of the mutation depends on genotypical factors other than the position of this mutation in BRCA1 gene. The results prompt screening for hereditary predisposition to these diseases.

BRCA1 Protein↗

[Analysis of mutations in the RET proto-oncogene in patients with medullary thyroid tumor].

The spectrum of mutations of the RET protooncogene was analyzed in Russian patients with inherited or sporadic medullary thyroid carcinoma (MTC). Four RET exons (11, 13, 15, and 16) were subjected to molecular analysis, and mutations were revealed and identified in 47.4% (9/19) patients with sporadic MTC. In total, six mutations (including three new ones) were observed. The most common mutation affected codon 918 to cause substitution of methionine with threonine and accounted for 31.6% alleles. Analysis of exons 11 and 16 revealed four mutations in patients with inherited multiple endocrine neoplasia type 2 (MEN 2). Mutations were found in each patient. Thyroidectomy was performed in four asymptomatic carriers of RET mutations from three MET 2A families (in two families, affected relatives had bilateral pheochromocytoma). In two patients, analysis of the surgery material revealed MTC microfoci in both lobes of the thyroid gland. The results provide the ground for constructing a bank of genetic information on Russian MTC patients with the clinically verified diagnosis.

Adolescent↗

[Molecular diagnosis of multiple type 2 endocrine neoplasia].

The paper reviews the data on the molecular structure of the protooncogene RET encoding for receptor-type protein kinase, on the mechanism of transformation of the normal protooncogene RET to a dominant transforming oncogene, and on RET mutations detected in patients with the MEN-2 syndrome. Moreover, it presents the authors' own findings. The familial medullary thyroid carcinoma burdened genealogy shows a new point mutation TCG(Ser)-->GCG(Ala) in codon 891, in the exon 15 of the protooncogene RET. This mutation was not detected in the chromosomes of healthy individuals. Analyzing the linkage with two known and two new polymorphic markers showed that there was a cisaggregation of informative polymorphic markers, phenotypic manifestation of the disease, and mutations in the genealogy in question. In the protooncogene RET, there were two new polymorphisms: G/A at position 24 in intron 14 and C/T in codon 836 (exon 14). The rate of the polymorphism encountered in codon 836 proved to be similar for the Russians and the Germans (0.96%), which was also seen for two earlier described polymorphisms in codon 691 (0.80 and 0.81, respectively) and in codon 904 (0.21 and 0.22). At the same time, there were statistically significant differences in the rates of intron 14 polymorphism (0.87 and 0.77, respectively). In a family having MEN 2, a proband displayed TGC-->CGC mutation in codon 634 of the gene RET in the heterozygous state. The mutation results in substitution of cysteine amino acid residue in the cysteine-rich extracellular domain of protein kinase encoded by the gene RET for arginine. The results of molecular analysis were used to confirm its clinical diagnosis and to indicate that effective care should be delivered in MEN 2a.

Alleles↗

[Hereditary cancer: identification, genetic heterogeneity, medico-genetic consult].

The paper deals with a role of inherited factors responsible for the occurrence of malignant tumors. Inherited types of cancer are shown to occur virtually at its sites and averaged 5-15%. Formalized criteria for identifying inherited cancer diseases and their etiological and genetic heterogeneity are presented. A role of genes that genetically predispose to particular forms of cancer is shown, which allows for early (preclinical) diagnosis and prevention of cancer diseases.

Genetic Counseling↗

[Molecular genetic aspects of neoplasms].

The paper presents data on the role of some genes that provide normal positive and negative regulation of cell proliferation. It considers their structural and functional changes that lead to the occurrence and progression of tumors. The characteristics of tumor suppressive genes whose inactivation determines hereditary predisposition to some forms of malignant neoplasms.

Biomarkers, Tumor↗

[Genetic-epidemiologic study of adenoma and cancer of the large intestine].

A clinical/genealogical study of colorectal adenomas (CRA) and cancer (CRC), and multiple primary malignant tumors (MPMT) was performed. The CRA prevalence in the population was 4.7 +/- 1.4% (single CRA--6.3% and multiple CRA--3.0%). The frequencies of malignant adenomas, 0.7% CRC, and MPMT were 0.7, 0.17 +/- 0.07%, and 0.004 +/- 0.003%, respectively. The prevalence of cancer of the female reproductive organs was also estimated (cancer of uterine body, 0.2 +/- 0.1%; cancer of ovaries, 0.08 +/- 0.1%; cancer of uterine cervix, 0.55 +/- 0.1%; cancer of mammary gland 0.57 +/- 0.1%). The main parameters of the familial inheritance of adenomas, CRC, and MPMT were also studied in general and at various clinical variants of these pathologies. Among the first-degree relatives of patients with solitary and multiple adenomas, the adenoma frequencies were 5.9 +/- 0.6 and 3.7 +/- 0.5%, respectively. The CRC frequency among the first-degree relatives of patients with adenoma was 3.0 +/- 0.6% and the frequency of MPMT was 5.8 +/- 0.6%. On the basis of the data obtained on frequencies of malignant tumors in various groups of relatives, the following conclusions were made: (1) in families of each proband group, specific pathology was accumulated; (2) the familial frequency of malignant tumors increased with an increase in proliferative processes and the severity of a pathology in probands.

Adenoma↗

[Segregation and genetic-dispersion analysis of predisposition to adenoma and cancer of the large intestine].

Segregation analysis of inheritance of adenomas, colorectal cancer (CRC), and multiple primary malignant tumors (MPMT) revealed their low penetrance: from 3.2 to 29% for homozygotes and from 2.0 to 14.4% for heterozygotes. This cast a doubt on the monogenic type of their inheritance, although it formally corresponded to the quasidominant type, i.e., only a fraction of heterozygotes was expressed. Therefore, the multifactorial model of inheritance was tested, which seemed more adequate because genetic heterogeneity of adenomas, CRC, and MPMT was suggested from the data on genetic correlations between various clinical forms. Predisposition to various clinical forms of adenomas, CRC, and MPMT was shown to be specific, i.e., the ratio between genetic and environmental predisposition-determining factors reflected pathogenetic differences between these diseases. However, analysis of variance which revealed genetic (pathogenetic) distinctions between adenomas, CRC, and MPMT is insufficient to confirm complete nosologic identity of each of these clinical forms.

Adenoma↗

[Genetic analysis and elaboration of principles for predicting malignant tumors in families of patients with stomach cancer and primary multiple malignant neoplasms].

The results of familial population analysis of stomach cancer and multiple primary malignant tumors (MPMTs) are presented. The data obtained provide evidence for the multifactorial nature of stomach cancer. Hereditary factors accounted for 32% of the general predisposition of individuals to stomach cancer. The age-related character of stomach cancer was established. Genetic heterogeneity of this tumor is suggested by the data obtained. Significant genetic commonness in the inheritance of stomach, colon, Genetic Analysis and Prognosis for Malignant Tumors in breast, endometrial, and ovarian cancer in families of MPMT patients was demonstrated on the basis of the obtained genetic correlations between tumor types in MPMT patients and solitary tumors in members of their families. The greatest genetic load was shown for families of MPMT patients, as compared with families of patients with solitary tumors, the coefficient of MPMT inheritance being equal to 77.4%. The data on the genetic character of stomach cancer and MPMT formed the basis for the identification of criteria for developing methodological approaches to the screening of individuals from risk groups to facilitate early diagnosis and prevention of cancer.

Age Distribution↗

[Clinico-genetic aspects of cutaneous melanoma. I. Incidence, familial study, genetic heterogeneity].

Epidemiologic and clinical genetic data on cutaneous malignant melanoma (CMM) are presented. The incidence of CMM in Moscow from 1983 to 1987 was analyzed. Cumulative incidence (cumulative risk) was calculated for various life periods on the basis of estimates for various age groups, which were used as population frequencies. By the age of 85, these frequencies were 0.35% for males and 0.38% for females. Among relatives of patients, the incidence of CMM was 1.420 +/- 0.498% for males and 1.110 +/- 0.348% for females; i.e., the incidence exceeded the population frequency by a factor of 3 or 4. As a whole, the familial frequency of cancer was equal to 13.3% for male probands and 14.2% for female probands, i.e., more than three times higher than the population frequency. The data obtained formed the basis for the development of CMM classification. hereditary and nonhereditary variants of cutaneous melanoma were identified. Familial cases and CMM that occurred against the background of inherited disease or syndromes were classified as hereditary variants of CMM; taken together, they accounted for 38.8%. The data provided grounds for identification of families at increased risk for the development of CMM.

Female↗

[Clinico-genetic aspects of cutaneous melanoma. II. Interconnection and pathogenetic commonality with dysplastic nevus syndrome].

Evidence for the role of dysplastic nevi (DN) in the development of cutaneous malignant melanoma (CMM) is presented. Primary multiple foci of CMM were found considerably more frequently in individuals with DN. The frequency of primary multiple CMM was found to be 3.1% in males with DN and 0.9% in males without DN; in females, 6.8 and 0.6%, respectively. Genetic correlation analysis was performed to determine the genetic interrelation between DN and CMM. In general, the genetic correlation coefficient was 0.9; i.e., predisposition to DN and CMM is determined by common genes for 90%. The frequency and distribution of constitutive fragile sites in chromosomes of peripheral lymphocytes was studied by the method of principal components for discrete variables. The site 1p22 is responsible for variability of the traits CMM and DN for 98.5%. On the one hand, this suggests that one of the supposed genes for CMM can be located at 1p22; on the other hand, CMM and DN are likely to have a common genetic determination or to be very tightly linked. Estimates of risk for the development of CMM in patients' relatives are given with reference to the variants of CMM manifestation and presence of DN.

Chromosomes, Human, Pair 1↗

[The medical genetic approach in the diagnosis of cancer].

Formation of registers of families afflicted by tumors of certain sites and dynamic follow-up of "healthy" members of such families is a new approach to early diagnosis and prevention of cancer. The results of a clinico-genetic study of hormone-dependent tumors of the female genitals and breast served as a basis for the development of a pattern of medico-genetic follow-up which, in turn, may facilitate integration of the above method with treatment for cancer of said and other sites.

Adolescent↗

[Melanoma of the skin: clinico-genetic studies].

As a result of clinico-genealogical analysis of data on 691 skin melanoma patients, a classification of skin melanoma was elaborated which reflected the etiologic heterogeneity of the disease. Inheritable and non-inheritable forms of skin melanoma were identified. The inheritable tumor group included familial disease (2%) and tumors developing against the background of hereditary diseases and syndromes (32.7%). The data obtained served as basis for the identification of families with high genetic predisposition to skin melanoma development and for the assessment of individual risk of the disease in patients' relatives.

Adult↗

[Malignant melanoma morbidity in Moscow].

The incidence of malignant melanoma of the skin in Moscow in 1983-1987 was studied. The average age-standardized index for the 5 years was 2.3% for males and 3.2% for females. The cumulative risk of the disease by the age of 75 years was 0.25% for males and 0.32% for females. The likelihood of skin melanoma development in each five-year age bracket appeared different and was characterized by a complex curve suggesting several etiologically heterogeneous forms of the disease.

Age Factors↗