[Show abstract][Hide abstract] ABSTRACT: Early diagnosis of prostate cancer (CaP) can be addressed by studying prostatic intraepithelial neoplasia (PIN) as precancer (high-grade PIN or HGPIN). This article attempts to analyze the diagnostic role of telomerase as an early marker of carcinogenesis.
[Show abstract][Hide abstract] ABSTRACT: In order to develop noninvasive diagnostics of bladder cancer (BC), telomerase activity has been examined by means the TRAP method (telomerase repeat amplification protocol) in tumor tissue and urine pellet samples taken from patients with bladder cancer. The levels of relative expression of genes encoding telomerase catalytic subunit (hTERT) and its RNA subunit (hTR) were evaluated by RT-PCR. Telomerase activity and expression of genes encoding its subunits were detected in both tumor tissues and in the urine cell pellet from each BC patient. Results of our study demonstrate possibility of noninvasive BC diagnostics using combination of these methods with sensitivity of 96% and specificity of 100% in the case of telomerase detection and with sensitivity of 80% and specificity of 100% in the case of hTERT detection in urine pellet samples.
Biochemistry (Moscow) Supplement Series B Biomedical Chemistry 01/2014; 8(1).
[Show abstract][Hide abstract] ABSTRACT: Comparative analysis of the inhibitory effect of modified DNA and RNA oligonucleotides on telomerase activity and tumor cell growth in vitro has been carried out. The study was performed with MCF-7, HeLa, and Mel-10 human cell line extracts. It was shown that PS-TelP5 and PS-TM024 phosphorothioate DNA oligonucleotides inhibited telomerase at nanomolar concentrations and suppressed the growth of tumor cells in vitro.
Applied Biochemistry and Microbiology 12/2011; 47(8). · 0.66 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Telomerase activity was examined in tissue specimens from patients with gastric adenocarcinomas and gastric lymphoma using
a modified TRAP (telomeric repeat amplification protocol) assay. Telomerase activity was found in 16 of 18 (89%) patients
with gastric adenocarcinomas and gastric lymphoma, whereas it was not detected in a patient with noncancerous gastric mucosa.
Almost all analyzed specimens had “high” and “very high” levels of telomerase activity. Telomerase is almost certainly associated
with the process of malignant transformation and it can be an important marker for diagnostics of gastric cancer.
Keywordsgastric adenocarcinoma–carcinogenesis–telomerase–telomerase activity (TA)
Biochemistry (Moscow) Supplement Series B Biomedical Chemistry 06/2011; 5(2):188-192.
[Show abstract][Hide abstract] ABSTRACT: Telomerase activity is detected in most types of human tumors, but it is almost undetectable in normal somatic cells; therefore,
telomerase is a promising therapeutic target. The present review describes various approaches to telomerase inhibition, namely,
antisense therapy, RNA interference, and the use of ribozymes and agents interacting with the telomeric G-quadruplex. The
use of these compounds in clinical research is analyzed in the review.
Keywordsantisense therapy–immortalization–G-quadruplex–ribozyme–RNA interference–telomerase activity
Applied Biochemistry and Microbiology 01/2011; 47(7):655-660. · 0.66 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Telomerase activity (TA) was examined in gastric adenocarcinomas and gastric lymphoma using a modified TRAP assay. TA was present in 16 of 18 (89%) gastric adenocarcinomas and in gastric lymphoma, whereas no TA was detected in normal tissue. Almost all samples had "high" and "very high" TA levels. Telomerase is undoubtedly associated with the process of malignant transformation and therefore can be an important marker for diagnostics of gastric cancer.
[Show abstract][Hide abstract] ABSTRACT: Demonstrated, that puncture thyroid hystobiopsy is safe and informative method of preoperative thyroid nodes diagnostics. Telomerase activity in tissue samples was significantly higher in case of malignant thyroid disease, although a positive correlation of telomerase activity was also with the amount of lymphocytes in bioptates. Combination of thyroid hystobiopsy with tissue telomerase activity measurement proved to be an effective means of preoperative diagnostic of patients with nodular goiter.
[Show abstract][Hide abstract] ABSTRACT: The detection of cholera enterotoxin in environmental objects and isolation of patients are considered to be the most reliable indices of that the cholera agent is present. Described in the case study is a method of nested polymerase chain reaction (PCR) based on amplifying the ctxA gene fragment coding subunit A of enterotoxin. A possibility was shown to use the above method to confirm the virulence of strains Vibrio cholerae isolated from different sources. The method was tested with 18 virulent and avirulent strains V. cholerae as well as (for the sake of verifying the analysis specificity) with DNAs of other human-pathogenic microorganisms and with the human genome DNA. The results showed a high efficiency of nested PCR in detecting the pathogenicity of cholera-agent strains.
[Show abstract][Hide abstract] ABSTRACT: To determine the causative agent of hepatitis A in the blood of patients, we developed the method of the nest polymerase chain reaction (PCR) with reverse transcription. For the comparative evaluation of the diagnostic efficacy of the nest PCR and the enzyme immunoassay (EIA) serum samples and mononuclear blood cells obtained from 15 patients with diagnosed hepatitis A and from 33 patients having signs and carrying markers of other form of hepatitis were analyzed. On the whole, the method of PCR confirmed the results of EIA and in some cases exceeded it in sensitivity. In addition, hepatitis A virus RNA was detected in the blood of a clinically healthy person having had a contact with a hepatitis A patient. The PCR data were shown to correlate with the activity of liver amino transferases. The results obtained in this study indicate that the field of the use of PCR in the analysis of hepatitis A virus may include cases of mixed infection and virus carriership.
Zhurnal mikrobiologii, epidemiologii, i immunobiologii 01/2004;
[Show abstract][Hide abstract] ABSTRACT: Imbalanced activity of the mechanism that controls cell division is a prerequisite for malignant transformation of a normal cell. The present review considers this multi-step mechanism, which is usually called the G1-S checkpoint. Besides, tumor cells are characterized by the presence of telomerase, an enzyme responsible for restoration of chromosome ends after replication and thus providing for unlimited cell division. The main point of the present article is to find out whether the activation of telomerase is controlled by the G1-S checkpoint or does not depend on it. The principal components of the G1-S checkpoint, such as cyclin-dependent kinases, retinoblastoma and E2F proteins, control the activity of telomerase. In their turn, they accumulate and transmit signals from various sources inside and outside the cell. Thus, various changes in tumor cells can activate telomerase through the G1-S checkpoint. Such are the suggested effects on telomerase of Myc, p53, Waf1, protein kinases B and C, Wnt5A, TGFbeta, WT1, and estrogens. However, Myc, p53, WT1, estrogens, protein kinases B and C, and TGFbeta can also directly influence telomerase independently of the G1-S checkpoint mechanism. Moreover, in 30% of human tumors the gene of the key subunit of telomerase (hTERT) is amplified, possibly due to chromosomal rearrangements unassociated with the activity of the G1-S checkpoint. Thus, telomerase seems to be activated not by a single agent but due to combined action of various factors, both with involvement of the G1-S checkpoint mechanism and independently of it.
[Show abstract][Hide abstract] ABSTRACT: The detection of the causative agent of hepatitis A in the patient's body is the necessary element of the diagnostics of this disease. In this work the PCR system for the analysis of the RNA of hepatitis A virus in the patient's blood is presented and characterized. The method of the detection of the RNA of hepatitis A virus is based on the "nest" principle and consists of two consecutive reactions. In the first reaction the reverse transcription and amplification with the external pair of primers are carried out. The product thus obtained is used as material for the second reaction with the internal pair of primers. This method was used for the study of 44 blood samples from hepatitis A patients and 23 blood samples from healthy donors. The detection rate of the RNA of hepatitis A virus in blood samples from the patients was 82%. Viral RNA could be detected in the serum in 72% of cases, both in the serum and in mononuclear blood cells in 20% of cases, in mononuclear blood cells only in 8% of cases.
Zhurnal mikrobiologii, epidemiologii, i immunobiologii 01/2004;
[Show abstract][Hide abstract] ABSTRACT: Causative agents of plague, i.e. bacterium Yersina pestis (in the subcutaneous tissues of rodents) and their cutaneous parasites need to be isolated to enable plague prevention. A comparatively new method of polymerase chain reaction (PCR) opens up new possibilities of determining Y. pestis just within several hours and without any cultivation. The article contains a description of the PCR-method, which makes it possible to distinguish the culture of Y. pestis from cultures of other microorganism, including speci of Yersina. The method is of the cluster-type, i.e. it is made up of subsequent PC reactions with the substrate for the second reaction being the product of the first one. The cluster nature of the method preconditions a higher sensitivity and specificity versus the ordinary PCR.
[Show abstract][Hide abstract] ABSTRACT: Herpes is one of the most widespread human viral pathologies. The article depicts a special modification of polymerized chain reaction--(PCR)--(referred to as "nested"), which has a higher sensitivity, specificity and reliability as compared to the ordinary PCR, and which is designed to detect the herpes viruses. The method was initially tested at purified preparation of viral DNA, and later--at clinical materials obtained from patients and healthy donors. Secretions from the urogenital tract (smears), scrapes from the urogenital tracts and urinal cellular samples were examined in patients. Herpes simplex was detected in all cases. As for the healthy people, the identical examinations produced in them mainly the negative findings. Therefore, the nested PCR is a simple, sensitive and effective instrument in the diagnostics and prevention of herpes; it can be recommended for a comprehensive usage in medical practice.
[Show abstract][Hide abstract] ABSTRACT: The effect of antisense oligonucleotides complementary to the RNA component of human telomerase on telomerase activity in cell extracts of the melanoma cell line SK-Mel-28 has been studied. It has been shown that the antisense oligonucleotide complementary to the hTR component in the region of the template synthesis of telomeric repeats is the most efficient inhibitor of telomerase activity in comparison with other antisense oligonucleotides. Pronounced inhibition of telomerase activity was observed at the oligonucleotide (Tel P5) concentration in the reaction mixture of about 5 nM. Complete inhibition of the enzyme occurs at the oligonucleotide concentration in the sample of about 20 nM.
Biochemical and Biophysical Research Communications 08/1998; 248(2):368-71. · 2.28 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Using thermophilic DNA-polymerase from Thermus thermophilus we have amplified by polymerase chain reaction (PCR) specific DNA sequences of Epstein-Barr virus (EBV) and human immunodeficiency virus (HIV). DNA-polymerase from Thermus thermophilus (molecular mass of 80-86 kDa) differs in its physico-chemical properties from DNA-polymerase from Thermus aquaticus (molecular mass of 62-68 kDa). To amplify the specific EBV DNA sequence, oligonucleotide primers for the virus replicon region (oriP region) were used. As a result of amplification, a specific 405-bp DNA fragment was produced.
Molecular and Cellular Probes 01/1991; 4(6):435-43. · 1.86 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The efficiency of phage DNA amplification by the method of polymerase chain reaction (PCR) with Tth DNA-polymerase was studied for optimization of PCR conditions. The effect on amplification efficiency of medium ionic strength and pH, the presence of univalent cations, detergents, gelatin, ATP, pyrophosphate, SH-reagents and ratio of concentrations of Mg and dNTPs, primers and template was studied. It has been found that a pH optimum for PCR with Tth DNA-polymerase varies from 8.5 to 9.0. An ionic strength optimum for PCR is about 0.08. The influence of univalent cations on the activity of Tth DNA-polymerase can be expressed as NH4+ greater than Na+ greater than K+. 0.01% Tween-20 significantly increases the efficiency of PCR and 0.01% gelatin inhibits it. Addition of ATP, pyrophosphate, SH-reagents to the reaction mixture did not increase the yield of PCR product. It has been also shown that for the given PCR-system an optimum Mg/dNTPs molar ratio is within the range of 1.5-2.0. An optimum concentration of each of the pair of primers for this PCR-system is about 0.3 microM. The possibility of PCR-amplification of 500-8500 b.p. DNA fragments has been demonstrated.
[Show abstract][Hide abstract] ABSTRACT: A thermoresistant htpR mutant having a decreased level of proteolytic activity has been selected in E. coli strain K802 after the directed mutagenesis in vivo. The mutation results in the bacteriophage T7 RNA-polymerase stability, aminoglycosidephosphotransferase stability as well as in the decrease in the rate of proteolytic degradation of cytoplasmic proteins during the heat shock. The obtained mutant strain can, probably be used as a host for alien polypeptides production.
Molekuliarnaia genetika, mikrobiologiia i virusologiia 10/1988;