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H Miyachi

Publications and source records attributed to H Miyachi.

At least 73 records · Page 4Linked to original sources

Quantitative analysis of human multidrug resistance 1 (MDR1) gene expression by nonisotopic competitive reverse transcriptase polymerase chain reaction assay.

We have established competitive reverse transcriptase polymerase chain reaction (RT-PCR) assay for the quantification of MDR1 mRNA encoding P-glycoprotein (P-gp) by analyzing leukemia sublines of MOLT-3 with various expression of MDR1. The expression was quantified by simultaneous RT-PCR of cellular RNA with decreasing amounts of heterologous competitor RNA, which shares the MDR1 primer sequences with the cellular MDR1 mRNA, but yields a different-sized PCR product. This allows resolution of the amplified cDNA fragments. The amounts of MDR1 mRNA measured by the assay were accurate and reproducible over wide range, and were determined as 31.6, 100, and 316 amol/microgram total RNA in MOLT-3/TMQ70, MOLT-3/ TMQ800, and MOLT-3/VCR1,000, respectively. The relative ratio of MDR1 mRNA measured by the competitive RT-PCR among three sublines was similar to that of MDR1 transcript determined by Northern analysis (1:4:12) and to that of P-gp measured by flow cytometry (FCM) analysis. In mononuclear cells from patients with leukemia, MDR1 mRNA could be sufficiently quantified by the competitive RT-PCR established, while FCM assay could scarcely detet P-gp. This study demonstrated that the competitive RT-PCR assay using heterologous competitor RNA is a rapid, reliable, and non-radioactive procedure and is acceptable for the evaluation of MDR1 expression in clinical samples.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

Cell type-/inducer-specific bidirectional regulation by thalidomide and phenylphthalimides of tumor necrosis factor-alpha production and its enantio-dependence.

Regulation by thalidomide and phenylphthalimide analogs (FPP-33 and PPS-33) of TNF-alpha production is specific to cell type and to inducer, i.e., (i) the compounds enhance TPA-induced TNF-alpha production by human leukemia HL-60 cells, while they inhibit TPA-induced TNF-alpha production by another human leukemia cell line, THP-1, and (ii) the compounds inhibit TNF-alpha production by both HL-60 and THP-1 cells when the cells are stimulated with okadaic acid (OA). The structure-activity relationships of these compounds are similar in the four assay systems (TPA/HL-60, TPA/THP-1, OA/HL-60, and OA/THP-1). However, optically active analogs, (S)- and (R)-alpha-methylthalidomides, show distinct bidirectional regulatory effects on TNF-alpha production, i.e., only the (S)-form shows TNF-alpha production-enhancing activity in the TPA/HL-60 assay system, while the (R)-form shows much more potent TNF-alpha production-inhibiting activity than the (S)-form in the other assay systems.

HL-60 Cells↗

Inducer-specific bidirectional regulation by thalidomide and phenylphthalimides of tumor necrosis factor-alpha production.

Regulation by thalidomide [N(alpha)-phthalimidoglutarimide] of tumor necrosis factor (TNF)-alpha production was found to be inducer-specific. Thalidomide enhances TNF-alpha production by human leukemia HL-60 cells induced with 12-O-tetradecanoylphorbol 13-acetate (TPA), while it inhibits TNF-alpha production induced with okadaic acid (OA) in the same cell line. Some phthalimide analogs, included PP-33 [2-(2,6-diisopropylphenyl)-1H-isoindole-1,3-dione] and its 4,5,6,7-tetrafluora derivative FPP-33), also showed such an inducer-specific bidirectional TNF-alpha production-regulating activity. The structure-activity relationships of the compounds tested are similar, but not identical, in the TPA-stimulated HL-60 and OA-stimulated HL-60 assay systems.

Carcinogens↗

The influence of drug-exposure conditions on the development of resistance to methotrexate or ZD1694 in cultured human leukaemia cells.

The influence of drug exposure conditions on the development of resistance to methotrexate (MTX) or ZD1694 was studied by treating MOLT-3 human lymphoblastic-leukaemia cells in a continuous or a pulsatile (high-dose, short term) drug-exposure schedule. Continuous exposure of the cells to MTX with stepwise escalation of the drug concentrations resulted in a MTX-resistant sub-line (MOLT-3/MTX(10000)) with impaired reduced-folate carrier (RFC) and increased dihydro-folate-reductase (DHFR) activity. Conversely, a MTX-resistant clone (MOLT-3/MTX. P-9) with unaltered RFC and DHFR activity, but with decreased cellular accumulation of anti-folates, was selected by high-dose short-term treatment of the cells with MTX. MTX resistance in the latter cells was pronounced after short-term rather than continuous-exposure incubation with MTX, suggesting defective polyglutamation of the drug. On the other hand, 2 ZD1694-resistant sub-lines which were established by continuous (MOLT-3/ZD1694. C) or by pulsatile drug-exposure schedule (MOLT-3/ZD1694.P-9) demonstrated extremely low accumulation and poor retention of [3H]ZD1694, with no change in initial drug uptake and little or no increase of thymidylate-synthase (TS) activity irrespective of drug exposure conditions for their establishment. HPLC analysis displayed a virtual absence of ZD1694 polyglutamates in both ZD1694-resistant sub-lines and low accumulation in MOLT-3/MTX.p-9 as compared to the parent line. However, folylpolyglutamate-synthetase(FPGS) mRNA was only moderately decreased in the 2 ZD1694-resistant sub-lines and to an even lesser extent in MOLT-3/MTX.p-9. In addition, gamma-glutamyl-hydrolase(GGH) activity was not increased, but was slightly down-regulated in the polyglutamation-defective sub-lines. These results indicate that the mechanism(s) of the resistance developed may depend not only on drug-exposure conditions while raising resistance but also on the biochemical properties of the drug.

Antimetabolites, Antineoplastic↗

Amplification of the thymidylate synthase gene in an N10-propargyl-5,8-dideazafolic-acid-resistant human leukemia, MOLT-3 cell line developed in pteroylglutamic acid, but not in leucovorin.

The types of folates used during the development of resistance to methotrexate have been suggested to play an important role in the mechanisms of established resistance. In this study, effects of reduced and oxidized folates on the development of resistance to a thymidylate synthase (TS) inhibitor, N10-propargyl-5, 8-dideazafolic acid (CB3717), were examined in the human leukemia cell line MOLT-3. MOLT-3 cells were made resistant to CB3717 by soft-agar cloning in RPMI-1640 medium with either pteroylglutamic acid (PGA) or a more physiological folate (10 nM leucovorin). A 40-fold CB3717-resistant subline developed in PGA (MOLT-3/CB3717(40)-PGA) showed amplification of the TS gene with a concomitant increased level in the gene expression. A 200-fold CB3717-resistant subline (MOLT-3/CB3717(200)-PGA), which was derived from MOLT-3/CB3717(40)-PGA, showed further enhancement of amplification of the TS gene. In contrast, even a 200-fold CB3717-resistant subline developed in leucovorin (MOLT-3/CB3717(200)-LV) showed neither amplification nor overexpression of the TS gene. Both MOLT-3/CB3717(200)-PGA and MOLT-3/CB3717(200)-LV cells showed decreased membrane transport of PGA as well as methotrexate. These results suggest that the types of folates used during the development of CB3717 resistance may play a role in resistance, and that impaired transport of PGA, in CB3717-resistant MOLT-3 cells developed in PGA, might have accelerated amplification of the TS gene.

Biological Transport↗

Cellular pharmacokinetics of ZD1694 in cultured human leukaemia cells sensitive, or made resistant, to this drug.

We have analysed the cellular metabolism of a novel thymidylate synthase (TS) inhibitor, ZD1694, in MOLT-3 and K562 human leukaemia cell lines sensitive to or made resistant to ZD1694 by continuous exposure of the cells to ZD1694 with stepwise escalation of the drug concentration. The initial cellular uptake of [3H]ZD1694 was greater in K562 cells than in MOLT-3 cells and the drug accumulated approximately 3-fold more in the former cells following incubation with 0.1 microM ZD1694 at 37 degrees C for 24 h. TS and dihydrofolate reductase activities were not significantly different between the two cell lines. After a 30-min incubation with the drug at 37 degrees C, 85% of the total drug (2.3 pmol/mg protein) in K562 cells was found as tri- to pentaglutamates, whereas MOLT-3 cells accumulated less drug in this time (0.83 pmol/mg protein) and polyglutamates of chain length greater than triglutamate were not found to a significant extent. When the incubation time was extended to 24 h, the polyglutamate profile in K562 cells was progressively shifted towards those of long glutamate chain length and 59% of the total cellular drug (204 pmol/mg protein) was identified as the penta form. In contrast, even distribution between tri- and pentaglutamate was observed in MOLT-3 cells. Total cellular polyglutamates were approximately 3-fold higher in K562 cells than in MOLT-3 cells, and this may explain the 2.5-fold difference in the sensitivity to ZD1694 between the two cell lines. Continuous exposure of MOLT-3 and K562 cells to ZD1694 up to 1 microM or 0.1 microM resulted in 1600- and 4200-fold resistant sublines, respectively (MOLT-3/ZD1694.C and K562/ZD1694.C). The resistant MOLT-3 cells showed a markedly lower cellular accumulation and poor retention of [3H]ZD1694 with no significant change of initial drug uptake by 10 min and with a little increase of TS activity. HPLC analysis demonstrated that more than 90% of the 3H co-eluted with the monoglutamate (parent drug) in the resistant MOLT-3 cells, indicating extremely diminished polyglutamation in the cells. On the other hand, cellular uptake of [3H]ZD1694 was extensively impaired in K562/ZD1694.C cells and cellular accumulation of the drug was only 2.5% of that in the parent cells following 24 h incubation with the drug. Neither an increase of TS or dihydrofolate reductase activity nor a change in the polyglutamate formation profile was observed in the resistant K562 cells. These results indicate that the cellular ability to produce the polyglutamate metabolites of ZD1694 must influence the sensitivity of the tumour cells to this drug, and development of mechanisms involved in the ZD1694 resistance may relate to the intrinsic biochemical properties of the cells.

Antimetabolites, Antineoplastic↗

In vivo evaluation of a fluorine-acryl-stylene-urethane-silicone antithrombogenic coating material copolymer for intravascular stents.

RATIONALE AND OBJECTIVES: We evaluated the effectiveness of a fluorine-acryl-styrene-urethane-silicone (FASUS) copolymer as an antithrombogenic coating material for intravascular stents in dogs. METHODS: FASUS copolymer-coated stents were placed in the right iliac veins, and uncoated 304 stainless steel stents were placed in the left iliac veins. We examined platelet deposition, microthrombus formation, and neointimal hyperplasia 4 weeks after stent placement by measuring the activity of 111In-labeled platelets, by using scanning electron microscopy, and by measuring neointimal thickness. RESULTS: Platelet deposition was significantly decreased on coated than on uncoated stents (p < .05). A less pronounced increase in red blood cell deposition was observed at the sites of the coated than uncoated stents (p < .05). Neointimal thickness 4 weeks after stent placement also was significantly less at the sites of the coated stents (0.27 +/- 0.08 mm versus 0.48 +/- 0.23 mm, p < .05). CONCLUSION: FASUS copolymer coating over the vascular stent is effective for preventing thrombus formation and neointimal hyperplasia.

Animals↗

Biological activity and intracellular metabolism of ZD1694 in human leukemia cell lines with different resistance mechanisms to antifolate drugs.

The biological activity and cellular metabolism of ZD1694, a novel folate-based thymidylate synthase (TS) inhibitor, were analyzed in a human leukemia cell line, MOLT-3, and its antifolate-resistant sublines with different mechanisms of resistance to methotrexate (MTX), trimetrexate (TMQ) and N10-propargyl-5,8-dideazafolic acid (CB3717). MOLT-3/CB3717(40), which was selected for CB3717 resistance, demonstrated impaired membrane drug transport via reduced folate carrier (RFC) and lower accumulation of [3H]ZD1694-polyglutamates in the cells with a shift in the polyglutamate distribution profile to shorter chain length polyglutamates, indicating an alteration in polyglutamation capacity in this subline. Impaired RFC and reduced rate of polyglutamation could explain the cross-resistance (12-fold) of this subline to ZD1694. On the other hand, there was little or no cross-resistance to this drug in a subline (MOLT-3/TMQ800) reportedly resistant to TMQ through impaired membrane transport for TMQ and an increase in dihydrofolate reductase (DHFR) activity. Total amount of ZD1694 polyglutamated to a level higher than diglutamate was approximately 1.7-fold higher in the TMQ-resistant cells than that in the parent cells, but a low degree of increase in TS activity in the cells counteracted the supposed increase in sensitivity to ZD1694. MOLT-3/TMQ800-MTX10000 cells, which were established by sequential exposure of the TMQ-resistant cells to MTX and were previously shown to amplify mutated DHFR with low affinity for MTX, showed a decreased accumulation of polyglutamated ZD1694 as compared with the parent line and this was consistent with cross-resistance to ZD1694 in this subline. Overproduction of variant DHFR scarcely influenced the sensitivity to this drug. These results indicate that ZD1694 could overcome antifolate resistance through a mechanism such as amplified DHFR activity, and the biological activity of this drug against the cells paralleled the amount of polyglutamated drug inside the cells. Determination of polyglutamation capacity in tumor cells may allow prediction of sensitivity to this drug.

Antimetabolites, Antineoplastic↗

Augmentation by phthalimides of phorbol ester-induced expression of tumor necrosis factor alpha message.

N(alpha)-Phthalimidoglutarimide (thalidomide), 2-(2,6-diisopropylphenyl)-1H-isoindole-1,3-dione (PP-33) and its 4,5,6,7-tetrafluoro derivative (FPP-33) augmented 12-O-tetradecanoylphorbol 13-acetate-induced production by human leukemia HL-60 cells of both tumor necrosis factor alpha (TNF-alpha) mRNA and secreted TNF-alpha protein. Intracellular TNF-alpha protein production was increased to a lesser extent.

Blotting, Northern↗

Inducer-specific regulators of tumor necrosis factor alpha production.

Novel potent regulators of tumor necrosis factor alpha (TNF-alpha) production by a human promyelocytic leukemia cell line, HL-60, were prepared. All the compounds showed inducer-specific and bidirectional regulation of TNF-alpha production, i.e., they enhanced 12-O-tetradecanoylphorbol-13-acetate-induced TNF-alpha production, while they inhibited okadaic acid-induced one.

Carcinogens↗

[Clinical diagnostic value of the PCR assay for detection of Mycobacterium tuberculosis].

To evaluate the clinical diagnostic value of the PCR assay for detection of M. tuberculosis, a total of 758 samples from 387 patients were assayed by the polymerase chain reaction (PCR) using the IS6110 gene as a target, and the results of the PCR assay were compared with those obtained by conventional culture. The patient's profiles such as clinical situation that required prompt differential diagnosis by the PCR assay, underlying disease and final diagnosis were analyzed. The PCR assay lead to the rapid diagnosis of tuberculosis which was confirmed by culture in all 56 cases including elderly and immunocompromised patients. One hundred and seventy-six of the 231 (76.2%) cases had abnormal shadows in the chest X-ray film that required the PCR assay for diagnosis of tuberculosis and differential diagnosis of pleural effusion, lung cancer or bacterial pneumonia. Negative PCR results were also used when active pulmonary tuberculosis had to be excluded. Forty-nine out of 95 cases (51.6%) with a final diagnosis of tuberculosis were in PCR-negative. The basis of the diagnosis in spite of the PCR negative results included positive culture results (8 cases) and histological findings (9 cases) in other specimens that were not subjected to PCR, radiological findings (24 cases), biochemical characteristics of pleural effusion (6 cases) or cerebrospinal fluid (1 case), and bronchoscopical findings (1 case). In 56 smear-negative patients with final diagnosis of pulmonary tuberculosis, the larger the number of specimens received for the PCR assay from each patient, the higher the frequency of positive cases; with 1, 2 and 3 specimens received for the PCR assay, 13.3% (4/30), 45.5% (5/11) and 60.0% (3/5) of cases were PCR positive, respectively. For the prompt diagnosis of tuberculosis by detection of tuberculous DNA using PCR, it is important to examine appropriate samples from the affected part of the patient and also to repeat the tests especially when the smear is negative.

Adolescent↗

[Direct detection of human cytomegalovirus in urine specimens from bone marrow transplant patients by polymerase chain reaction].

Human cytomegalovirus (HCMV) infection is a major causative life-threatening agent that results in opportunistic infections in bone marrow transplant patients. Since antiviral therapy is available for severe HCMV infections, methods to rapidly identify infected patients are needed so that therapy can be promptly instituted. In this study, we used direct method to detect HCMV in urine specimens by nested polymerase chain reaction (nested-PCR) to monitor urinary excretion of HCMV in patients undergoing bone marrow transplantation. The viral DNA was amplified directly from preheated urine without further treatment prior to amplification. Five microliter of urine proved to give the most efficient amplification. The detection limit of the PCR assay for detection of HCMV was 10 copies/microl. The positive rate of the PCR assay and the tissue culture method for detection of HCMV were 15 of 61 (24.6%) and 4 of 61 (6.6%), respectively. Sensitivity and specificity of the PCR assay were 100% and 81% respectively. Based on these data, urinary excretion of HCMV in 21 patients undergoing bone marrow transplantation were monitored weekly by the PCR assay. As a result, in addition to a higher sensitivity, the PCR assay allowed to identify HCMV infection 3.1 (1 approximately 5) weeks earlier than culture method or antibody elevation. Repeated monitoring of virus excretion by this rapid and simple method was useful to promptly detect HCMV infection, allowing proper institution of antiviral drug therapy in patients undergoing bone marrow transplantation.

Adolescent↗

Expression of variant dihydrofolate reductase with decreased binding affinity to antifolates in MOLT-3 human leukemia cell lines resistant to trimetrexate.

Various alterations of the dihydrofolate reductase (DHFR) gene are involved in resistance. In order to understand the mechanism that induce such gene alterations in human leukemia cells, we studied the expression products of DHFR gene in trimetrexate (TMQ)- and/or methotrexate (MTX)-resistant sublines derived from a MOLT-3 human leukemia cell line. A 200-fold TMQ-resistant subline (MOLT-3/TMQ200) expressed the mutated DHFR mRNA, with a base change (T-->C) at the second position of codon 31, as well as the wild type gene. A MTX-resistant subline derived from MOLT-3/TMQ200 (MOLT-3/TMQ200-MTX500) showed a further increase in the expression of the mutated DHFR mRNA, compared to MOLT-3/TMQ200, with a marked decrease of expression of the wild type DHFR mRNA, which is confirmation of amplification of the mutated DHFR gene. By contrast, a 10,000-fold MTX-resistant subline (MOLT-3/MTX10,000) over-expressed the wild type DHFR mRNA, which is confirmation of amplification of the wild type gene. Increased levels of the DHFR enzyme in these sublines were proportional to expression levels of the DHFR mRNA. The DHFR enzyme expressed in MOLT-3/TMQ200-MTX500 cells showed a 40-fold increase in the Ki values for both MTX and TMQ, compared with values for the wild type DHFR expressed in both MOLT-3/MTX10,000 and its parent cell line. These findings suggest that the altered DHFR gene, which was introduced in MOLT-3 cells by exposure to TMQ, gave rise to a variant enzyme with reduced affinity to antifolates, and that complex DHFR alterations confer drug-resistant phenotypes in antifolate-resistance. Structural difference between the antifolates could be important in the introduction of the differential DHFR gene alterations in the antifolate resistance.

Base Sequence↗

Effect of hammerhead ribozyme against human thymidylate synthase on the cytotoxicity of thymidylate synthase inhibitors.

One of the resistance mechanisms to folate-based thymidylate synthase (TS) inhibitors is the increase in TS activity in tumor cells. Human B lymphoblastoid cell line (W1L2) was made resistant to a lipophilic non-polyglutamatable TS inhibitor (ZM249148), and the subline (W1L2:R179) showed a 20-fold increase in TS enzyme activity with concomitant overexpression of TS mRNA. To overcome the resistance, we designed a ribozyme that can cleave the CUC sequences in a triple tandemly repeated sequence of TS mRNA. Expression of this ribozyme in W1L2:R179 cells transfected with Epstein Barr virus-based expression vector resulted in sensitization to TS inhibitors concomitantly with a decrease of TS expression. The ribozyme expressed in transfectants was shown to be functional in cleaving artificial TS RNA in vitro.

B-Lymphocytes↗

[Detection of Mycobacterium tuberculosis by amplification of mycobacterial DNA from pleural fluid and gastric juice: the comparison of IS6110 gene with Amplicor mycobacterium].

The polymerase chain reaction (PCR) using oligonucleotides based on the repetitive sequence (IS6110) of Mycobacterium tuberculosis and Amplicor Mycobacterium, which combines a PCR with the hybridization assay, were evaluated for detection of M. tuberculosis in pleural fluid and gastric juice. The detection limits of these two assay systems for cultured M. tuberculosis were less than 2 cells/ml, as compared with 200 cells/ml by culture. A total of 42 pleural fluid and 94 gastric juice specimens were examined. A total of 5 pleural fluid and 5 gastric juice were culture positive for M. tuberculosis. Only the PCR gave positive results in 2 pleural fluid of which laboratory findings are characteristic of tuberculous pleuritis, and in one gastric juice of the patient who was diagnosed as having pulmonary tuberculosis. Sensitivity, specificity and positive predictive value for IS6110 gene were 75%, 94% and 71.1%, respectively, in pleural fluid. Two of three positive specimens for IS6110 gene from pleural fluid were negative for Amplicor Mycobacterium. These specimens resulted in positive with Amplicor Mycobacterium when solvent extracted DNA was used. Both the PCR systems had the same sensitivity (80%), specificity (98.8%) and positive predictive value (83.3%) in gastric juice. The PCR systems would be useful for rapid detection of M. tuberculosis without long term culture and for detection of non-cultured one from pleural fluid as well as gastric juice. However, when the presence of an inhibitor of PCR is suspected in a specimen, DNA should be purified from the specimen before amplification.

Adult↗

[Rapid detection and identification of mycobacteria by the PCR assay based on the co-amplification of the gene IS6110 and groEL].

In definite diagnosis of mycobacterial infection, prompt and adequate differential diagnosis leads to an appropriate treatment. We developed and evaluated a PCR assay based on co-amplification of the insertion sequence IS6110 and groEL gene that are species-specific for Mycobacterium tuberculosis complex and genus-specific, respectively. The detection limit of the assay system for cultured M. tuberculosis was 2 cells/ml, as compared with 200 cells/ml by culture onto Ogawa's medium. To assess the value of the assay in routine laboratory works, the results obtained by PCR were compared with those by standard microbiological methods for 758 specimens collected for the examinations of mycobacterial infection. The PCR system for detection of mycobacteria gave overall positive rate of 27.6% (209/758), as compared to 6.1% (46/758) by smear and 7.7% (58/758) by culture onto Ogawa's medium. Sensitivity and specificity were 97.8% and 97.3%, respectively, for the IS6110 and groEL gene for detection of M. tuberculosis complex; 91.7% and 80.3%, respectively, for only the groEL gene for detection of atypical mycobacteria. The PCR assay based on co-amplification of the IS6110 and groEL gene would be useful for diagnosis of mycobacterial infections, allowing not only more sensitive detection of mycobacteria but also rapid discrimination between M. tuberculosis complex and atypical mycobacteria. This assay would help to eliminate time-consuming confirmation, and to avoid both unnecessary treatment and hospitalization of the patient.

DNA, Bacterial↗

[Gene level diagnostics of infectious diseases].

Recent developments in medical technology have caused a great change in infectious diseases, as characterized by epidemics of antibiotics-resistant bacteria, opportunistic infection in compromised hosts, and blood-borne viral infections such as hepatitis virus and human immunodeficiency virus. In the diagnosis of such new aspects of infectious diseases, conventional immunological, culture, and microscopical techniques are not always practical. By contrast, evaluation of infectious agents using molecular biological technology frequently offers the rapid, most accurate and sensitive method of diagnosis. Amplification methods are particularly attractive for the detection of small numbers of microorganisms, as in latent conditions, or for the fastest identification of the pathogen without laborious isolation. For introduction of the tests into routine procedures, their standardization as well as simplicity and low cost are required. Gene level diagnostics should be applied appropriately to management of infectious diseases along with the conventional techniques, while further roles of the tests must be determined, on the basis of the molecular elucidation of infectious diseases.

DNA, Bacterial↗

[Detection of mycobacterial DNA by in vitro enzymatic amplification in lung nodular lesions in a patient with ovarian immature teratoma].

We experienced a 13-year-old girl with ovarian immature teratoma, who presented multiple pulmonary nodular lesions. Thoracotomy was performed to rule out the metastatic tumor. Histopathological study of the resected tumor suggested a possible diagnosis of tuberculosis. However, neither the acid-fast staining nor the mycobacterial culture of the specimens confirmed the diagnosis. Polymerase chain reaction (PCR) and hybridization technique successfully detected specific DNA sequence for M. tuberculosis from the specimens. The lesions regressed after anti-mycobacterial therapy. Detecting mycobacterial DNA by PCR, which led to a proper diagnosis and treatment of this patient, is a rapid and sensitive method in diagnosis of tuberculosis. This method is recommended to distinguish tuberculosis from neoplastic lesions of the lung, where surgical intervention is necessary.

Adolescent↗