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Background: Tobacco chewing is attributed to oral cancer. Prediction of cancer development by genotoxicity analysis is a major challenge to identify tobacco users at greater risk. Therefore, present study aimed to analyze tobacco related genotoxic effects in chewers monitoring micronuclei (MN) and chromosome aberrations (CA). The biomarkers were compared with non chewer to (i) predict risk for genotoxicity, (ii) estimate synergistic effect of tobacco exposure with level of biomarkers, and (iii) identify best cellular site of measurements for genotoxicity assessment. Methods: Healthy tobacco chewers (n=47); and controls (n=48) were enrolled in the study. The peripheral blood lymphocyte and exfoliated buccal mucosa cells were studied for CA and micro nucleated cell count (MNC) respectively. An arbitrary unit was obtained for Lifetime Tobacco Exposure (LTE) using frequency/day multiplied by duration of years of tobacco use. Data were analyzed using SPSS statistical software. Results: MNC was significantly higher (p=0.001) in chewers than controls. CA was higher in chewers than controls. MNC can differentiate higher tobacco exposure in chewers than CA. Controls having MNC above cutoff level have greater risk of genotoxic exposition (95% C.I.; 1.462-23.26, p=0.012). Conclusion: The present study concludes that MNC is a better surrogate biomarker to predict genotoxicity than CA for tobacco exposure and DNA damage index in tobacco chewers [ABSTRACT FROM AUTHOR]

Background: To evaluate prognostic effect of submicroscopic deletions involving breakage and fusion points of the derivative chromosome 9 and 22 in chronic myeloid leukemia in untreated patients and their follow up samples to correlate with disease outcome. Methods: The study included 78 pretreatment (PT) samples from CML patients and 90 follow-up samples, classified as complete responders (CR, n=33), nonresponders (NR, n =54), and partial responder (PR, n=3) depending on the treatment status of the follow-up samples. Karyotype analysis was performed on metaphases obtained through short term cultures of bone marrow and blood. Detection of BCR-ABL fusion gene was performed using dual color dual fusion (D-FISH) translocation probes. Results: BCR-ABL fusion gene detection by D-FISH showed ABL-BCR deletion on derivative 9 in 47.8% of nonresponders which was higher as compared to pretreatment (11%). Mix D-FISH signal pattern was found in around 20% of pretreatment and non-responder samples. Average interval from chronic phase to blast crisis and accelerated phase was respectively 3.5 and 18 months and accelerated to blast crisis was 16.5 months from the time of diagnosis. The follow-up duration of 31 patients responded to therapy was significantly higher (p=0.0001) as compared to 45 patients who did not respond to therapy. Variant D-FISH signal pattern was seen at the time of diagnosis in patient who responded to therapy as well as those patients who did not respond to therapy. Conclusion: This is the first study from India reporting deletion in ABL, BCR, or ABL-BCR on derivative 9 did not correlate with response to therapy. [ABSTRACT FROM AUTHOR]

Background: To evaluate prognostic effect of submicroscopic deletions involving breakage and fusion points of the derivative chromosome 9 and 22 in chronic myeloid leukemia in untreated patients and their follow up samples to correlate with disease outcome. Methods: The study included 78 pretreatment (PT) samples from CML patients and 90 follow-up samples, classified as complete responders (CR, n=33), nonresponders (NR, n =54), and partial responder (PR, n=3) depending on the treatment status of the follow-up samples. Karyotype analysis was performed on metaphases obtained through short term cultures of bone marrow and blood. Detection of BCR-ABL fusion gene was performed using dual color dual fusion (D-FISH) translocation probes. Results: BCR-ABL fusion gene detection by D-FISH showed ABL-BCR deletion on derivative 9 in 47.8% of nonresponders which was higher as compared to pretreatment (11%). Mix D-FISH signal pattern was found in around 20% of pretreatment and non-responder samples. Average interval from chronic phase to blast crisis and accelerated phase was respectively 3.5 and 18 months and accelerated to blast crisis was 16.5 months from the time of diagnosis. The follow-up duration of 31 patients responded to therapy was significantly higher (p=0.0001) as compared to 45 patients who did not respond to therapy. Variant D-FISH signal pattern was seen at the time of diagnosis in patient who responded to therapy as well as those patients who did not respond to therapy. Conclusion: This is the first study from India reporting deletion in ABL, BCR, or ABL-BCR on derivative 9 did not correlate with response to therapy. [ABSTRACT FROM AUTHOR]

Background: Tobacco chewing is attributed to oral cancer. Prediction of cancer development by genotoxicity analysis is a major challenge to identify tobacco users at greater risk. Therefore, present study aimed to analyze tobacco related genotoxic effects in chewers monitoring micronuclei (MN) and chromosome aberrations (CA). The biomarkers were compared with non chewer to (i) predict risk for genotoxicity, (ii) estimate synergistic effect of tobacco exposure with level of biomarkers, and (iii) identify best cellular site of measurements for genotoxicity assessment. Methods: Healthy tobacco chewers (n=47); and controls (n=48) were enrolled in the study. The peripheral blood lymphocyte and exfoliated buccal mucosa cells were studied for CA and micro nucleated cell count (MNC) respectively. An arbitrary unit was obtained for Lifetime Tobacco Exposure (LTE) using frequency/day multiplied by duration of years of tobacco use. Data were analyzed using SPSS statistical software. Results: MNC was significantly higher (p=0.001) in chewers than controls. CA was higher in chewers than controls. MNC can differentiate higher tobacco exposure in chewers than CA. Controls having MNC above cutoff level have greater risk of genotoxic exposition (95% C.I.; 1.462-23.26, p=0.012). Conclusion: The present study concludes that MNC is a better surrogate biomarker to predict genotoxicity than CA for tobacco exposure and DNA damage index in tobacco chewers. [ABSTRACT FROM AUTHOR]