A complete diagnostic procedure was developed that allows single molecules of mRNA AML1-ETO to be detected in samples of whole blood and bone marrow of the leukemia t(8;21)(q22;q22) patients. The procedure includes: a method for preservation of biological samples ensuring the RNA integrity; an improved method for isolation of RNA from the unfractionated whole blood and bone marrow; an optimized reverse transcription; and the use of nanocolonies for detection and enumeration of RNA target molecules. The developed procedure is the first one that provides for determination of the absolute titer of an RNA target without reference to a control (housekeeping) gene, and significantly increases sensitivity, precision and reliability of detection of the minimal residual disease at a leukemia associated with known chromosomal translocation.

Using computational methods for analysis of electronic databases we identified a number of human nucleotide sequences expressed predominantly in tumors. We experimentally studied one of the sequences, which is related to the UniGene database cluster Hs.633957 and located near the telomere in the chromosome 7p22.3. All the RNA sequences of the cluster Hs.633957 are non-coding and their role was not described yet, but expression pattern of the locus makes it theoretically and practically interesting. Here we studied expression of the sequence Hs.633957 in various normal and tumor tissues using reverse transcription polymerase chain reaction. Of all the normal adult tissues studied weak expression was only identified in heart and liver. It was also identified in embryonic brain and kidney. Locus Hs.633957 is expressed in tumors of various tissue origin including tumors of lung, intestines, breast, stomach, cervix, lymph nodes and others. Thus the Hs.633957 locus is expressed predominantly in tumors and may be considered a prospective tumor marker.

The main function of Csk tyrosine kinases is phosphorylation of the C-terminal part of Srk tyrosine kinases as a mechanism of their downregulation. A decrease in the expression of csk gene results in the enhancement of Srk tyrosine kinase activity. In this study, cDNA containing the full coding sequence of the human leukocyte Csk tyrosine kinase gene has been cloned. The protein encoded by a a 1624-bp cDNA fragment has 99% homology to human Csk tyrosine kinase. A comparative sequence analysis of full-length cDNAs for Csk tyrosine kinase of normal lymphocytes and lymphocytes of patients with choroidal melanoma revealed a nucleotide substitution in dexon 10 of the gene, which appears to be of diagnostic significance. It has been shown that the risk of choroidal melanoma correlated with the frequency of this allele.

The expression of mRNA of proteins involved in the transformations of cytostatics (cytochrome P-450 1A1 and 1B1 isoforms) and genes encoding proteins participating in their regulation (Ah receptor, AHRR and ARNT) in intestinal tumors and intact portions of the intestine were studied. The expression of cytochrome P-450 1A1 increased in poorly differentiated tumors in comparison with its expression in intact portions of the intestine (tumor/intact tissue=1.65). The expression of cytochrome P-450 1B1 was higher in well-differentiated tumors (tumor/intact tissue=1.62). The possibility of practical use of high expression of cytochrome P-450 isoforms in tumors in comparison with intact intestinal tissue is discussed.

The frequencies of chromosome 9 abnormalities in children with hematological neoplasia have constituted: 25/112 in acute lymphoblastic leukemia (ALL), 10/83--in acute myeloid leukemia (AML), 3/20--in refractory anemia (RA). The frequency of deletions was higher than of translocations in ALL. Deletions were found as sole abnormalities as in complexity karyotypes. More often the rearrangements affected bands 9q34 and 9q22. Translocation t (9;22)(q34; q11) occured in 7.1% cases ALL. In AML the translocations were detected with greater frequency than deletions. The long arm bands 9q22 and 9q34 were more often involved in structural rearrangements. Deletions, translocations and duplications were registered in MDS. Comparison with clinical features showed no correlation with age and the main hematological indexes including the amount of blast cells in initial period. Multidrug resistance and disease progression during chemotherapy were noted in t (9;22).

Studies of expression of BCL-2 gene family revealed abnormal regulation of biosynthesis of apoptosis-related proteins in tumour cells involved in the development and progress of neoplastic diseases. Expression of BCL-2 proteins in highly differentiated gastric and colonic tumours was roughly 1.2 times lower than in the normal cells. A 3.5-fold rise in BCL-2 expression was documented in a group of moderately differentiated adenocarcinomas and undifferentiated tumours. The most striking (9-fold) difference between BCL expression in untransformed and atypical cells was recorded in moderately differentiated metastatic colonic adenocarcinoma. Immunohistochemical studies of BAX expression in untransformed and atypical gastric and colonic cells demonstrated activation of apoptosis-inducing mechanisms in the pathologically changed tissue. Investigations with the use of SSCP showed that 20% of the patients had BAX gene mutations affecting codons 38 to 41 of exone 3. This region was found to contain octadeoxyguanosine G8 sequence. The mutations were caused by deletion of G7 or insertion of G9.

We have examined the existence of intratumoral genetic heterogeneity for LOH on chromosomes 9p21 (p16, p15, p19), 13p14 (RB1), 10q23 (PTEN), 17p (TP53), microsatellite instability and K-RAS point mutations on four different segments of sporadic colorectal cancers. The intratumoral genetic heterogenity was detected in 9/11 (81%) colorectal adenocarcinomas and morphologically validated. These results show that colorectal cancer is highly heterogeneous for these molecular markers. Furthermore, the analysis has shown the order (succession) of the appearance of these molecular anomalies during tumorigenesis on sporadic CRC, and supposed, that K-RAS point mutations, and anomalies of p16-RB1-cyclin D pathway could occur before LOH on 10q23 (PTEN) and microsatellite instability during tumor progression.

Inhibiting gene expression in specific tissues and organs through intravenous injection would be the ultimately preferred method of disease therapy. Here, we report the successful delivery of lentivirus-mediated small interfering RNA (siRNA) to suppress the GFP gene expression in living mice. First, a lentiviral vector with siRNA (len-siRNA) driven by H1 promoter was constructed to suppress GFP expression effectively in Mel cells. When the len-siRNA virus was injected into transgenic mice, the GFP expression was significantly suppressed (over 15% reduction) in the recipient mice compared to the control mice and the suppressing effect lasted more than one week after injection. Our results demonstrate a new effective approach to inhibit gene expression by siRNA and lentiviral vectors. Further development of this suppression of gene expression siRNA drug should result in applications not only for cancers but also for infectious and immune diseases.

Chromosomal and genome abnormalities of 3p are frequent events in many epithelial tumours, including lung cancer. Several critical regions with high frequency of hemi--and homozygous deletions in tumours were detected on 3p and more then 20 different cancer-related genes were identified in 3p21.3 locus. Real-time PCR was used to measure mRNA level of tumour-suppressor genes and candidates in 3p21.3 (RBSP3/CTDSPL, NPRL2/G21, RASSF1A, ITGA9, HYAL1 and HYAL2 in basic types of non-small cell lung cancer (NSCLC)--squamous cell lung cancer (SCC) and lung adenocarcinoma (AC). Significant (from 2 to 100 times) and frequent (from 44 to 100%) mRNA level decrease was shown in NSCLC. Level and frequency of mRNA decrease for all genes depended on histological type of NSCLC. Down-regulation of RASSF1A and ITGA9 was associated significantly with AC progression, the same tendency was found for genes RBSP3/CTDSPL, NPRL2/G21, HYAL1 and HYAL2. On the contrary, down-regulation of all genes in SCC was not associated with clinical stages, tumor cells differentiation and metastases in lymph nodes. Significant decrease of RBSP3/CTDSPL, NPRL2/G21, ITGA9, HYAL1 and HYAL2 mRNA levels (on average, 5-13 times) with high frequency (83-100%) was already shown at the first stage of SCC. Simultaneous decrease of all six genes mRNA level was found in the same tumor samples and was not depended on their localization on 3p21.3 and functions of the proteins. Spearman's correlation coefficient r(s) was from 0.63 to 0.91, P < 0.001. Co-regulation of gene pairs ITGA9 and HYAL2, HYAL1 and HYAL2, which mediate cell-cell adhesion and cell-matrix interaction, was suggested based on the obtained data. It was shown that genetic and epigenetic mechanisms were important for down-regulation of RBSP3/CTDSPL and ITGA9 genes. These results supported the hypothesis on simultaneous inactivation of cluster cancer-related genes in extended 3p21.3 locus during development and progression of lung cancer and other epithelial tumors. Significant and frequent decrease of mRNA level of six genes in SCC could be important for development of specific biomarker sets for early SCC diagnosis and new therapeutic approaches/strategies for NSCLC.

Glucose intolerance and insulin resistance belong to the group of leading risk factors for breast (BC) and endometrial cancer (EC). Differences in the intensity of association of these endocrine disturbances with BC and EC may at least partly be explained by non-identity in polygenic nature of the mentioned hormone-metabolic shifts and oncological diseases themselves as well. In this study, which included 105 healthy postmenopausal women and 301 female cancer patients (110 BC and 191 EC) without overt diabetes mellitus, we compared the frequency of the following genetic polymorphisms: insulin receptor substrate-1, IRS Gly972Arg; leptin receptor, LEPR Lys109Arg and Gln223Arg; mitochondrial uncoupling protein-2, UCP2_866G/A; and gene ND3 of mitochondrial DNA, mtDNA 10398A/G. Genotyping was performed with allele-specific real-time PCR. According to data received, certain genetic markers associated with impaired glucose tolerance and/or insulin resistance (namely, leptin receptor genotypes 223 Gln/Arg and Gln/Gln) are revealed in oncological patients more often than in females without cancer. Other markers (like genotype UCP2 866AA and polymorphism mtDNA 10398A) appeared to be relatively more frequent in EC than in BC providing one of the interpretations for the lower insulin sensitivity and higher incidence of carbohydrate metabolism disturbances in the first of these two diseases.

The study included 67 breast cancer patients and 147 healthy controls--residents of the city of Novosibirsk. HLA association with tumor cell differentiation pattern and grade was established in breast cancer patients. -A19, -B27, -DR1, -DR6 (p < or = 0.01) and -A1, -A2, -B12, -B35, -B40 (p < or = 0.05) were shown to be associated with disease while -DR3, -DR4 and -B15--with resistance to it. Absence of metastasis to the lymph nodes was associated with -B16 and -B35, and -A19/DR2, -B35/DR1: local metastases -B40 in combination with -A1, -A10, -DR2 and A10/DR2; metastases to the regional lymph nodes--with -B5, -B17 and phenotypes-- -A2/B5, -B5/B18. Well differentiated cell tumors were associated with -A3, -A19, -B7, -B12, -B-35 in combination with -DR1, -DR2, -DR5 and phenotypes-- -A3/A19 and -A1/B35; moderately-- -B40 and -DR1; phenotypes-- -A1/B40, -B27/DR1, -B40/DR1; poorly differentiated cell tumor-- -A19, -DR6 and -A2/-A19, -A9/DR6, -B40//DR6. HLA testing may be instrumental as an additional means of prognosis for beast cancer.

In this article the role of immunoregulative system and cellular genome (p53 and sFAS/FASL) pathology biomarkers and oncological markers (cancer fetal antigene and CA19-9) was estimated in results of surgical treatment in complex with the various kinds of a clinical nutrition in the early postoperative period after colon cancer.

A history of the discovery, hypotheses of the pathogenesis, neuromorphologic data, clinical appearances, differential diagnostics and an own description of a single case of rare hereditary children leukoencephalopathy, with megalencephaly, changes of myelin structure and formation of subcortical cysts are presented. Taking into account non-specific clinical appearances of this disease and difficulties of genetic analysis, a priority role of MRI-diagnostics revealing typical signs of the disease is emphasized.

Recent advances of molecular genetics have made a noticeable impact in some areas of clinical medicine. Almost comprehensive understanding of the nature of hereditary tumors is frequently heralded as the most substantial practical achievement of molecular oncology. Proper diagnostic algorithms have already been developed for the vast majority of known familial cancer syndromes. Interestingly, an unexpectedly strong "founder" effect has been documented at least for some hereditary cancers occurring in Russia, that significantly simplifies the detection of the corresponding disease-associated gene variants. The number of tests aimed to customize cancer treatment continues to grow every year. EGFR mutation test appears to be the most impressive, as it allows to predict lung cancer response or non-response to gefitinib or erlotinib with indeed unique level of accuracy. The approaches helping to determine individual efficacy and safety profiles for fluoropyrimidines, platinum compounds, irinotecan etc. are currently under development Methods aiming to detect residual amounts of disseminated cancer cells represent another popular avenue of the research. It is expected that these technologies will improve the quality of prediction of local and distant metastases, facilitate monitoring of the minimal residual disease and, in the long perspective, provide the tool for early cancer diagnosis. One has to remember that the molecular detection of disseminated tumor cells is currently used mainly in research settings and is not yet incorporated into routine clinical practice.

The paper deals with a history of radiobiological investigations carried out at the Center since 1925 which have contributed to the present-day conception on the influence of damaged DNA on stochastic (carcinogenesis) and non-stochastic (accelerated aging) late radiation pathology in exposed biological objects. A phenomenological and pathogenetic similarity of somatic (in irradiated organisms) and genetic (in progeny of irradiated parents) consequences of exposure to ionizing radiation is suggested and our data are presented pointing to a possibility of germ cells of irradiated parents to transmit genomic instability to the progeny thus increasing risk of carcinogenesis.

The immunohistochemical investigation used 55 primary hepatic tumors (hepatocellular carcinoma (HCC)--32, cholangiocellular carcinoma (CCC)--23). Wide panels of such antibodies as hepatocytic marker (Hep Par--1) CK-8, CK-19, polyclonal CEA, CD10, alpha-fetoprotein, TTF-1 as well as proliferative features of HCC (Ki-67) including regulators of stage-to-stage transition through mitoses of tumor cells (cyclin-D1 and A, genes p53 and RB), unrestricted tumor cell mitosis (telomerases), and intercellular adhesion marker (beta-catenin) were employed for differential diagnosis of neoplasia. The most efficient marker HCC was Hep Par--l (sensitivity--100%, specificity--92%) while the sensitivity of CCC (CK-19) was 83% and specificity--78%. Of particular importance for differentiation between HCC and CCC were the nature of microcirculatory flow identifiable with the aid of CD31 and presence of pseudocapsule in HCC detected by means of calponin. CEA and CD10 played a part too while the remaining markers were either expressed very seldom (alpha-fetoprotein) or absent (TTF-1). Most nuclear antigens (Ki-67, cyclin-A, p53 and RB) were intensely expressed in poorly-differentiated HCC cells. Cyclin-D1 and mutated suppressor-gene p53 expression involved lowered overall and relapse-free survival.

Survivin (BIRC5) is one of the members of IAP-family apoptosis inhibitors. The BIRCS gene is expressed in most human embryonic tissues and malignant tumors but not in normal differentiated tissues of adult human. It was suggested that BIRC5 proteins inhibit apoptosis and play an essential role in tumorigenesis, makings surviving an attractive target for anticancer therapy. The mechanisms regulating level of survivin are not completely understood. It was supposed that natural inhibitors of survivin, namely SMAC and PML, play an important role in these processes. Using RT-PCR and immunoblotting we analyzed the transcription level of BIRC5, SMAC and PML genes and content of corresponding proteins in normal and tumor human tissues in non-small cell lung cancer and esophageal squamous cell carcinoma. It was demonstrated that BIRC5 is transcribed only in tumor tissues, whereas expression levels of SMAC and PML are the same in normal and tumor tissues. The contents of proteins correspond to levels of mRNA of the respective genes. Thus the increase of level of survivin in tumor tissues is not the result of decrease in content of its inhibitors SMAC and PML, as their content in tumor and normal cells is the same.