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)

Complete 1H-nmr data and unambiguous assignments of the 13C-nmr spectra of phyllanthin [1] and hypophyllanthin [2] were obtained through extensive nmr studies, including homonuclear COSY, homonuclear decoupling, APT, HETCOR, nOe difference, selective INEPT, and COLOC experiments. The absolute configuration of hypophyllanthin [2] was determined by cd. Neither of these lignans demonstrated significant cytotoxic activity when evaluated with a battery of cultured mammalian cells, but both were found to enhance the cytotoxic response mediated by vinblastine with multidrug-resistant KB cells. In addition, 1 was found to displace the binding of vinblastine with membrane vesicles derived from this cell line, suggesting an interaction with the P-glycoprotein.
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PMID:1H- and 13C-nmr assignments of phyllanthin and hypophyllanthin: lignans that enhance cytotoxic responses with cultured multidrug-resistant cells. 838 84

A major problem with cancer chemotherapy begins when cells acquire resistance. Drug-resistant cancer cells typically upregulate multi-drug resistance proteins such as P-glycoprotein (P-gp). However, the lack of overexpressed surface biomarkers has limited the targeted therapy of drug-resistant cancers. Here we report a drug-delivery carrier decorated with a targeting ligand for a surface marker protein extra-domain B(EDB) specific to drug-resistant breast cancer cells as a new therapeutic option for the aggressive cancers. We constructed EDB-specific aptide (APTEDB)-conjugated liposome to simultaneously deliver siRNA(siMDR1) and Dox to drug-resistant breast cancer cells. APTEDB-LS(Dox,siMDR1) led to enhanced delivery of payloads into MCF7/ADR cells and showed significantly higher accumulation and retention in the tumors. While either APTEDB-LS(Dox) or APTEDB-LS(siMDR1) did not lead to appreciable tumor retardation in MCF7/ADR orthotropic model, APTEDB-LS(Dox,siMDR1) treatment resulted in significant reduction of the drug-resistant breast tumor. Taken together, this study provides a new strategy of drug delivery for drug-resistant cancer therapy.
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PMID:A drug-delivery strategy for overcoming drug resistance in breast cancer through targeting of oncofetal fibronectin. 2776 87