Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.6.3.44 (P-glycoprotein)
 13,344 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The doxorubicin-selected lung cancer cell line H69AR is resistant to many chemotherapeutic agents. However, like most tumor samples from individuals with this disease, it does not overexpress P-glycoprotein, a transmembrane transport protein that is dependent on adenosine triphosphate (ATP) and is associated with multidrug resistance. Complementary DNA (cDNA) clones corresponding to messenger RNAs (mRNAs) overexpressed in H69AR cells were isolated. One cDNA hybridized to an mRNA of 7.8 to 8.2 kilobases that was 100- to 200-fold more expressed in H69AR cells relative to drug-sensitive parental H69 cells. Overexpression was associated with amplification of the cognate gene located on chromosome 16 at band p13.1. Reversion to drug sensitivity was associated with loss of gene amplification and a marked decrease in mRNA expression. The mRNA encodes a member of the ATP-binding cassette transmembrane transporter superfamily.
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PMID:Overexpression of a transporter gene in a multidrug-resistant human lung cancer cell line. 809 49

Here we report a rare chromosomal translocation, t(12;22)(p13;q11), which was detected in a 53-year-old female patient diagnosed as having minimally differentiated acute myeloid leukemia (AML-M0) according to the French-American-British classification criteria. Chromosome painting analysis with probes for chromosomes 12 and 22 confirmed the result of the conventional cytogenetic analysis. Reverse transcriptase polymerase chain reaction revealed the TEL-MN1 fusion transcript. Interestingly, she presented primary multidrug resistance and did not respond to several kinds of chemotherapy regimens. Moreover, she could not achieve remission after two doses of monotherapy with Mylotarg. Flow cytometry analysis detected high levels of expression of P-glycoprotein, multidrug-resistant-related protein, lung-related protein, and glutathione S-transferase pi in this case at presentation. As far as we know, this is the first report of t(12;22)(p13;q11) translocation involving TEL and MN1 genes in an AML-M0 patient.
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PMID:Minimally differentiated acute myeloid leukemia with t(12;22)(p13;q11) translocation showing primary multidrug resistance and expressing multiple multidrug-resistant proteins. 1747 96

t(17;19)(q21-q22;p13), responsible for TCF3-HLF fusion, is a rare translocation in childhood B-cell precursor acute lymphoblastic leukemia(BCP-ALL). t(1;19)(q23;p13), producing TCF3-PBX1 fusion, is a common translocation in childhood BCP-ALL. Prognosis of t(17;19)-ALL is extremely poor, while that of t(1;19)-ALL has recently improved dramatically in intensified chemotherapy. In this study, TCF3-HLF mRNA was detectable at a high level during induction therapy in a newly diagnosed t(17;19)-ALL case, while TCF3-PBX1 mRNA was undetectable at the end of induction therapy in most newly diagnosed t(1;19)-ALL cases. Using 4 t(17;19)-ALL and 16 t(1;19)-ALL cell lines, drug response profiling was analyzed. t(17;19)-ALL cell lines were found to be significantly more resistant to vincristine (VCR), daunorubicin (DNR), and prednisolone (Pred) than t(1;19)-ALL cell lines. Sensitivities to three (Pred, VCR, and l-asparaginase [l-Asp]), four (Pred, VCR, l-Asp, and DNR) and five (Pred, VCR, l-Asp, DNR, and cyclophosphamide) agents, widely used in induction therapy, were significantly poorer for t(17;19)-ALL cell lines than for t(1;19)-ALL cell lines. Consistent with poor responses to VCR and DNR, gene and protein expression levels of P-glycoprotein (P-gp) were higher in t(17;19)-ALL cell lines than in t(1;19)-ALL cell lines. Inhibitors for P-gp sensitized P-gp-positive t(17;19)-ALL cell lines to VCR and DNR. Knockout of P-gp by CRISPRCas9 overcame resistance to VCR and DNR in the P-gp-positive t(17;19)-ALL cell line. A combination of cyclosporine A with DNR prolonged survival of NSG mice inoculated with P-gp-positive t(17;19)-ALL cell line. These findings indicate involvement of P-gp in resistance to VCR and DNR in Pgp positive t(17;19)-ALL cell lines. In all four t(17;19)-ALL cell lines, RAS pathway mutation was detected. Furthermore, among 16 t(1;19)-ALL cell lines, multiagent resistance was usually observed in the cell lines with RAS pathway mutation in comparison to those without it, suggesting at least a partial involvement of RAS pathway mutation in multiagent resistance of t(17;19)-ALL.
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PMID:Resistance of t(17;19)-acute lymphoblastic leukemia cell lines to multiagents in induction therapy. 3130 9