Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2009-2-9
pubmed:abstractText
Drug resistance is a major drawback for cancer chemotherapy protocols and previous studies have demonstrated the overexpression of the P-glycoprotein (P-gp) as mechanism by which myeloma cells develop multidrug resistance (MDR). However, other molecules may apparently promote MDR in multiple myeloma (MM). They include both lung resistance-related protein (LRP) and p53 activation. The inhibition of P-gp in MM patients treated with melphalan (PAM) has been associated to increased toxicity, whereas defective apoptosis due to down-modulation of the NF-kB is a feature of MDR+ myeloma cells. On the contrary, clinical trials with proteasome inhibitors have been successfully carried out to overcome MDR despite their toxicity profile. Recently, sigma receptors (sigmaR)(S), namely sigmaR(1) and sigmaR(2), have been found to be overexpressed in breast cancer cells. In addition, their levels correlate with both P-gp upregulation and MDR development. By contrast, selective inhibitors of sigmaR(S) as PB28, disrupt the P-gp signals and restore the apoptosis machinery in malignant cells. We have reviewed the major pathogenetic events promoting MDR in MM and focused on the sigmaR(S) as potential mechanism driving this function. We demonstrate that MDR+ myeloma cells overexpress the sigmaR(2) and that the treatment with PB28 induces P-gp down-modulation through the activation of the caspases enrolled in both extrinsic and intrinsic apoptotic pathways. Thus, sigmaR(2) inhibitors may be tentatively proposed for the treatment of PAM-resistant MM patients.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
1873-4294
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
9
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
218-24
pubmed:meshHeading
pubmed:year
2009
pubmed:articleTitle
Role of active drug transporters in refractory multiple myeloma.
pubmed:affiliation
DIMO, Department of Internal Medicine and Clinical Oncology, University of Bari, Italy. m.tucci@dimo.uniba.it
pubmed:publicationType
Journal Article, Review, Research Support, Non-U.S. Gov't