Smokeless tobacco (ST), an alternative to smoking, has gained wide popularity among tobacco users. This study is conducted to determine the time course of gene expression associated with specific signaling pathways in...Smokeless tobacco (ST), an alternative to smoking, has gained wide popularity among tobacco users. This study is conducted to determine the time course of gene expression associated with specific signaling pathways in human oral epithelial cells after exposure to smokeless tobacco extract (STE). A differentiated layer of epithelial cell is created as a way to mimic reasonably similar physiological atmosphere. A dose and time dependent response is observed for cell viability and cell proliferation assays indicating that this model system is responsive to the treatment. Expressions of 84 genes representing 18 different signal transduction pathways are quantitated. This is accomplished by using real-time polymerase chain reaction arrays at 1 h, 3 h, 6 h and 24 h time points following exposure to STE. Changes in gene expression are observed on many cellular processes including cell cycle regulation, cell adhesion, inflammation, apoptosis, and DNA breaks-down including Akt pathway activation. Short time exposure (1 h) leads more genes to down regulate whereas longer incubation time results in more genes up regulation. Most notable differences in the expression of genes during the course of treatment are BCL2A1, BIRC3, CCL20, CDK2, EGR1, FOXA2, HOXA1, IGFBP3, IL1A, IL-8, MMP10, NOS2, NRIP1, PTGS2, SELPLG and TNF-a. This study provides an insight on gene expression on oral epithelial cells as a result of STE exposure. This may also postulate greater understanding on biological effects and the mechanism of action of STE particularly at the transcriptional level.展开更多
The so-calledPhiladelphia(Ph) chromosome is present in more than 90% of chronic myeloid leukemia (CML) cases. It results in juxtaposition of the 5' part of the BCR gene on chromosome 22 and the 3' part of the ...The so-calledPhiladelphia(Ph) chromosome is present in more than 90% of chronic myeloid leukemia (CML) cases. It results in juxtaposition of the 5' part of the BCR gene on chromosome 22 and the 3' part of the ABL1 gene on chromosome 9. An additional acquired monosomy 7 or deletion of 7q is associated with poor prognosis in a variety of myeloid disorders. Here we report a novel Ph chromosome positive CML case with a ring chromosome 7 [r(7)]. Immunophenotyping was compatible with CML, although 4.5% of total leucocytes appeared like acute myelogeneous leukemia (AML) subtype M2. The r(7) was characterized in detail by array-proven multicolor banding (aMCB), the latter being of enormous significance to characterize breakpoint regions in detail. Underlying mechanisms and prognostic are discussed, as ring chromosomes are rare cytogenetic abnormalities in hematopoietic malignancies.展开更多
文摘Smokeless tobacco (ST), an alternative to smoking, has gained wide popularity among tobacco users. This study is conducted to determine the time course of gene expression associated with specific signaling pathways in human oral epithelial cells after exposure to smokeless tobacco extract (STE). A differentiated layer of epithelial cell is created as a way to mimic reasonably similar physiological atmosphere. A dose and time dependent response is observed for cell viability and cell proliferation assays indicating that this model system is responsive to the treatment. Expressions of 84 genes representing 18 different signal transduction pathways are quantitated. This is accomplished by using real-time polymerase chain reaction arrays at 1 h, 3 h, 6 h and 24 h time points following exposure to STE. Changes in gene expression are observed on many cellular processes including cell cycle regulation, cell adhesion, inflammation, apoptosis, and DNA breaks-down including Akt pathway activation. Short time exposure (1 h) leads more genes to down regulate whereas longer incubation time results in more genes up regulation. Most notable differences in the expression of genes during the course of treatment are BCL2A1, BIRC3, CCL20, CDK2, EGR1, FOXA2, HOXA1, IGFBP3, IL1A, IL-8, MMP10, NOS2, NRIP1, PTGS2, SELPLG and TNF-a. This study provides an insight on gene expression on oral epithelial cells as a result of STE exposure. This may also postulate greater understanding on biological effects and the mechanism of action of STE particularly at the transcriptional level.
文摘The so-calledPhiladelphia(Ph) chromosome is present in more than 90% of chronic myeloid leukemia (CML) cases. It results in juxtaposition of the 5' part of the BCR gene on chromosome 22 and the 3' part of the ABL1 gene on chromosome 9. An additional acquired monosomy 7 or deletion of 7q is associated with poor prognosis in a variety of myeloid disorders. Here we report a novel Ph chromosome positive CML case with a ring chromosome 7 [r(7)]. Immunophenotyping was compatible with CML, although 4.5% of total leucocytes appeared like acute myelogeneous leukemia (AML) subtype M2. The r(7) was characterized in detail by array-proven multicolor banding (aMCB), the latter being of enormous significance to characterize breakpoint regions in detail. Underlying mechanisms and prognostic are discussed, as ring chromosomes are rare cytogenetic abnormalities in hematopoietic malignancies.
