[Immunohistochemical diagnosis of metastases of small round cell carcinomas with undetected primary focus].

17 small round cell tumors of unkown primary site were studied. The main location was lymph nodes and brain. Immunohistochemical study was performed. One of the following diagnosis was obtained in 14 cases (82.4%): small cell carcinoma, Merkel cell carcinoma, melanoma, Ewing sarcoma family tumor. In other three cases (17.6%) tumor histogenesis was not determined definitively.

[Molecular markers of various stages of nonsmall cell lung cancer development]. / Molekuliarnye markery razlichnykh stadii razvitiia nemelkokletochnogo raka legkogo.

Studies performed in the recent decade in the Laboratory of the Regulation of Cell and Virus Oncogenes associated structural and functional defects of several oncogenes and tumor suppressor genes with various stages of non-small-cell lung cancer. High risk of lung cancer was established for carriers of rare alleles of the Hras1 minisatellite, the hypermethylated p16INK4A promoter, and microsatellite defects in chromosome regions 3p12, 3p14.2, 3p22-24, 3p21, 3p25, 9p21, and 17p13. Analysis of the Hras1 minisatellite and microsatellites located in two minimal deletion overlap regions of 1p36 was shown to allow a more reliable prognosis in lung cancer. The results testified again that panels of molecular markers are useful for individual risk assessment, early and differential diagnosis, and prognosis in cancer.

[Development of chronic obstructive pulmonary disease correlates with mini- and microsatellite locus instability]. / Razvitie khronicheskikh obstruktivnykh boleznei legkikh korreliruet s nestabili'nost'iu mini- i mikrosatellitnykh lokusov.

Allele distribution at a highly polymorphic minisatellite adjacent to the c-Hras1 gene as well as deletions of microsatellite markers, D3S966, D3S1298, D9S171, and a microsatellite within p53 gene, were examined in bronchial epithelium specimens obtained from 53 chronic obstructive pulmonary disease (COPD) patients and healthy donors. A higher frequency of rare Hras1 minisatellite alleles in COPD patients than in the individuals without pulmonary pathology (6.6% versus 2.2%; P < 0.05) was shown. This difference was most pronounced in the group of ten COPD patients with idiopathic pulmonary fibrosis. Three of these patients had rare Hras1 minisatellite allele (P < 0.02 in comparison with healthy controls). Alterations in at least one of the microsatellite markers (deletions or microsatellite instability) were detected in bronchial epithelium samples obtained from: 4 of 10 COPD patients with pneumofibrosis (40%); 15 of 43 COPD patients (34.9%) without pneumofibrosis; and 8 of 20 tobacco smokers (40%) without pulmonary pathology. These defects were not observed in the analogous samples obtained from healthy nonsmoking individuals. No statistically significant differences were revealed between COPD patients and healthy smokers upon comparison of both the total number of molecular defects and the number of defects in the individual chromosomal loci. The total number of molecular defects revealed in bronchial epithelium samples from the individuals of two groups examined correlated with the intensity of exposure to tobacco smoke carcinogens (r = 0.28; P < 0.05). These findings suggest that rare alleles at the Hras1 locus may be associated with hereditary predisposition to COPD and the development of pneumofibrosis, while mutations in microsatellite markers result from exposure to tobacco smoke carcinogens and are not associated with the appearance of these pathologies.

[Suppression of the metastatic potential of oncogene v-src-transformed cells as a result of activity of the exogenous DAP kinase]. / Podavlenie metastaticheskogo potentsiala kletok, transformirovannykh onkogenom v-src, kak rezul'tat aktivnosti ékzogennoi DAP-kinazy.

Hamster tumor cell lines obtained with the Rous sarcoma virus and characterized by a high metastatic activity in vitro were transfected with the gene for C2+/calmodulin-dependent serine-threonine death-associated protein kinase (DAPk). Expression of DAPk in tumor cells dramatically reduced their survival in the blood of syngenic animals and their ability to produce metastases, but did not affect their tumorigenicity or the primary tumor growth. The DAPk-induced change in the metastatic phenotype was not accompanied by substantial changes in production and phosphorylation of v-Src or focal adhesion proteins (focal adhesion kinase and paxilline). The resulting system of transfected cells with a modulated metastatic potential provide a convenient model to study the molecular mechanisms of tumor progression at various steps.

[Increased risk of occurrence of pulmonary adenocarcinoma in man is associated with the presence of rare alleles of the Hras1 minisatellite]. / Povyshennyi risk vozniknoveniia adenokartsinom legkogo u cheloveka assotsiiruetsia s nalichiem redkikh allelei minisatellita Hras1.

Data on allelotyping of minisatellite sequence within the Hras1 protooncogene locus in 60 patients with lung adenocarcinoma (LAC) are presented. Allele distribution was analyzed with respect to the effect of tobacco smoke carcinogens (smoking factor). Results were compared with the analogous data obtained for patients with squamous-cell-carcinoma and for individuals without cancer. In contrast to the patients with squamous cell-carcinoma, the frequency of the Hras1 locus rare alleles in patients with lung-adenocarcinoma was higher than in individuals without cancer. More striking difference between the latter groups was demonstrated for nonsmoking patients (17.6% versus 2.7% of healthy individuals, P = 0.0005). In smoking LAC patients, higher frequencies of the common a4 allele (2.5 kb in size under the MspI/HpaII digestion) were found. Our findings point to the combined effect of endogenous and exogenous factors on the development of lung adenocarcinomas in humans. In this work, we discuss the possible mechanism of association between the rare minisatellite alleles and the predisposition to lung cancer.

[Restriction polymorphism of the proto-oncogene c-Ha-ras-1 in patients with multiple primary malignant neoplasms and non-small-cell lung cancer]. / Restriktsionnyi polimorfizm protoonkogena c-Ha-ras-1 u patsientov s pervichno-mnozhestvennymi zlokachestvennymi novoobrazovaniiami i nemelkokletochnkym rakom legkogo.

Restriction fragment length polymorphism in the human c-Ha-ras-1 locus, associated with a minisatellite sequence, was examined in 45 multiple primary cancer (MPC) patients, 56 patients with squamous cell lung cancer (SCLC), 21 patients with lung adenocarcinoma (LAC), and 53 individuals having no oncopathology. Southern analysis of cellular DNA revealed the presence of 4 common alleles (with collective allele frequency close to 94% in the control group) and a set of rare alleles. Allele a3, (2.1 kb in size under MspI/HpaII digestion) was shown to be more frequent in the MPC than in the control group. The same tendency was observed in the patients with highly differentiated cell lung cancer. An increased frequency of the a4 allele (2.5 kb under MspI/HpaII digestion) was observed in the patients with adenocarcinomas as well as in the patients with metastases and low levels of tumor tissue differentiation. The elevated frequencies of a3 in the MPC group and of a4 in the LAC patients did not correlate with increased risk of the cancers mentioned above but was associated with type of tumor progression. Previously, it was reported that the mini-satellite sequence within the c-Ha-ras-1 locus possesses enhancer activity. Our data indirectly confirm the hypothesis that the efficiency of minisatellite modulator activity is associated with fragment size.

[Cloning cDNA for the ha-SDGF gene from a Syrian hamster cell line with increased metastatic potential using subtractive hybridization]. / Klonirovanie s pomoshch'iu vychitaiushchei gibridizatsii kDNK gena ha-SDGF iz linii kletok siriiskogo khomiachka s povyshennym potentsialom metastazirovaniia.

Using subtractive hybridization, a cDNA library containing over 50% of clones specific for a highly metastatic cell line was obtained from two hamster embryo fibroblast lines with different metastatic potentials. Most of the clones (83%) contained new sequences. One clone contained the ha-SDGF gene cDNA homologous to SDGF cDNA from rodents. The level of ha-SDGF mRNA expression was considerably higher in the highly metastatic cell line.

[Effect of specific activation of phosphatidylcholine metabolism in hamster fibroblasts transformed by Rous sarcoma virus]. / Effekt spetsificheskoi aktivatsii obmena fosfatidilkholina v fibroblastakh khomiaka, transformirovannykh virusom sarkomy Rausa.

Transformation of embryonic hamster fibroblasts by the Rous sarcoma virus results in sharp increase of the turnover rate of one of cellular phospholipids-phosphatidylcholine. The decrease in the rate of virus-transformed cells (HETSR strain) during the monolayer formation is attended by additional activation of phosphatidylcholine turnover. A similar effect is observed after prolonged culturing of cells with dexamethasone. Addition of the tyrosine kinase inhibitor, genistein, to cells leads to selective inhibition of phosphatidylcholine synthesis without any effect of phosphoinositide synthesis. Immunoblotting analysis of p60-src, the product of the viral oncogen v-src related to the tyrosine kinase family failed to produce any significant changes in protein synthesis and activity during dexamethasone-induced inhibition of HETSR cell growth. The data obtained testify to selective activation of phosphatidylcholine metabolism in src-transformed cells which enhances with a decrease in the rate of cell growth. The presence in HETSR cells of p60-src whose synthesis is not controlled by dexamethasone may be responsible for increased phosphatidylcholine metabolism and sustaining cell growth under conditions of limited activity of growth-promoting compounds.

[Expression of the v-src oncogene in Escherichia coli affects the rate of cell growth and leads to phosphorylation of cellular proteins]. / Ekspressiia onkogena v-src v Escherichia coli vliiaet na skorost' rostakletok i privodit k fosforilirovaniiu kletochnykh belkov.

The possible influence of expression of v-src oncogene harboring tyrosine-specific protein kinase activity on the physiological state of E. coli cells, carrying plasmid which expresses src oncoprotein was studied. The realization of this activity in the cells brings to the phosphorylation of tyrosine in some additional cellular proteins and, as a consequence, to an increased proliferative activity of cells expressing src oncoprotein.

[A new recipient cell line for transfection of biologically active oncogenes]. / Novaia retsipientnaia kletochnaia liniia dlia transfektsii biologicheski aktivnykh onkogenov.

The properties of the new immortalized rat cell line (REF-1) were analyzed. These cells can be used as recipient ones in transfection assays. REF-1 cells never convert spontaneously to transformed phenotype during long-term passages in vitro unlike NIH3T3 cells. This peculiarity allowed to use REF-1 cells for identification of oncogenes, which induce slow-growing tumors. The following oncogenes were used in gene transfection experiments in order to test their effects: activated human EJ-ras; N-ras; v-myc; v-mos; activated tpr-met and c-hu-met. REF-1 cells, transfected with the members of ras family; v-mos and tpr-met were found to be transformed in vitro and induce tumors in nude mice, on the contrary of c-hu-met- and v-myc-transfected cells, which are non-tumorogenic. A number of clonal cell lines carrying different oncogenes were obtained. The detailed analyses of integration and expression of exogenous sequences of different oncogenes has been presented in 18 clonal cell lines.

[The effect of Ha-ras oncogene on cells immortalized by the gene for polyomavirus large T-antigen]. / Deistvie onkogena Ha-ras na kletki, immortalizovannye genom bol'shogo T-antigena virusa poliomy.

Activated human Ha-ras oncogene cloned on the plasmid pEJras6,6 was transfected into REF (LT) cells immortalized by the gene for large T-antigen of the polyoma virus. The cells were shown to become completely transformed (in the terms of morphology and tumorogeneity) only after three cycles of transfection with the plasmid pEJras6,6. The integrated sequences of the plasmid pEJras6,6 and the ras oncogene product p21Ha-ras were detected in cells only after their selection in the nude mice (in the cell culture REF (LT) ras X 3tu obtained from the tumor and directly in the tumor cells). Thus, after sequential transfections with a c-Ha-ras oncogene we developed cell cultures on the different stages of transformation process.

[Differences in the distribution of proviruses in low- and highly- metastatic variants of hamster cells, transformed by Rous sarcoma virus]. / Razlichiia v raspredelenii provirusov v nizko- i vysoko- metastaticheskikh variantakh kletok khomiakov, transformirovannykh virusom sarkomy Rausa.

The structure of provirus in Syrian hamster cells, transformed by Rous sarcoma virus (RSV) varying in metastatic capability in vivo has been analysed. The original cell line and its low metastatic variants contain only one copy of the integrated RSV genome. The DNA of highly metastatic cell lines cloned from the same primary culture, contain an additional copy of provirus. This RSV copy in different highly metastatic variants has a similar integration site.

[Transcription and expression in Escherichia coli of src gene cloned sequences of rous sarcoma virus]. / Transkriptsiia i ékspressiia v Escherichia coli klonirovannykh posledovatel'nostei gena src virusa sarkomy rausa.

Effective transcription of virus-specific sequences was shown in Escherichia coli cells that carry recombinant plasmids pPrC11 and psrcC with fragments of the Rous sarcoma virus (RSV) genome. Analysis of transcripts revealed several classes of RNA, one of which is probably transcribed from the structural part of the RSV src gene. Analysis of the primary structure of the region adjacent to the src RSV gene showed the existence of sequences similar to the bacterial promoters from which the src-specific RNAs can be transcribed. The synthesized RNA directs the translation of a functionally active protein product, that has tyrosine-specific phosphoproteinkinase activity.

[Transfection of a plasmid with a retrovirus promoter: distribution of sequences in the genome of induced tumors]. / Transfektsiia plazmidy s retrovirusnym promotorom: raspredelenie posledovatel'nostei v genome indutsirovannykh opukholei.

The structure of the integration site of plasmid with LTR of Rous sarcoma virus (pLTR1,5) in the genome of nude mice tumors, induced as a result of N1H3T3 cells' implantation, cotransfected by pLTR1,5 with the DNA of malignant human glioma cells, carrying amplified c-Ha-ras genome, has been studied. The restriction map of the investigated region of the cell genome was obtained. Molecular cloning of the integrated plasmid and adjacent cell sequences has been carried out. It was shown that the exogenic vector in the DNA of the tumor cells is included in BamHI structure of the repeat of mice genome.

[Induction of unstable mutations in Drosophila melanogaster by microinjection of DNA from oncogenic viruses into the embryo polar plasma. II. Analysis of the role of injected DNA]. / Induktsiia nestabil'nykh mutatsii u Drosophila melanogaster mikroin''ektsiei DNK onkogennykh virusov v poliarnuiu plazmu émbrionov. Soobshchenie II. Analiz roli in''etsiruemoi DNK.

We have demonstrated that the mutagenic effect of oncovirus DNA injected into Drosophila embryos is of two-type locus specificity: the spectrum of mutations induced by the retroviral cDNA (RSV) changed in different recipient stocks and those induced by the adenoviral DNA (Sa7) did not differ in the stocks studied. The Sa7 DNA and the cDNA of RSV induce mutations in different groups of loci. Transpositions of the copia element were found in mutant lines obtained in both cases.

[Characteristics of genome sequences in mouse spleen cells activated in virus-induced Rauscher leukemia]. / Kharakteristika genomnykh posledovatel'nostei kletok selezenki myshei, aktiviruiushchikhsia pri virusindutsirovannom leikoze Raushera.

The restriction analysis of BALB/c and AKR mice genome DNA was used to show the translocation and amplification of gene which is expressed with the Rauscher erythroleukemia as the 35S nuclear RNA. The homology of this RNA to 10 defined oncogenes was studied. It was found that the cDNA 35S RNA is efficiently hybridized only with v-sis oncogene. The clones homologous to the 35S RNA, v-sis oncogene and 3'-area of the Rauscher leukemia virus genome are isolated from the genes' library of mice erythroleukemic cells.