A Single Nucleotide Polymorphism (SNP) in the SLC22A3 Transporter Gene Is Associated With the Severity of Oral Mucositis in Multiple Myeloma Patients Receiving Autologous Stem Cell Transplant Followed by Melphalan Therapy.

BACKGROUND: It has been reported that expression of OCT3 enhanced the sensitivity to melphalan in cells, indicative of potential roles of OCT3 in melphalan transport. Herein we investigated the association of select single nucleotide polymorphisms in SLC22A3 (gene encoding OCT3) with clinical outcomes in multiple myeloma (MM) patients with hematopoietic autologous stem cell transplants followed by high-dose melphalan therapy. MATERIALS AND METHODS: Melphlan concentrations in blood samples from 108 MM patients were measured using liquid chromatography-tandem mass spectrometry (LC-MS/ΜS); genotypes of rs2048327, rs1810126, and rs3088442 in these patients were determined using quatitive RT-PCR assays. RESULTS: Rs3088442 A variant-carriers had a significantly increased risk of severe oral mucositis in comparison with homozygous rs3088442 G-carriers with adjusted odds ratio of 4.00 (95% CI=1.25-14.7; p=0.027). Rs3088442 A carriers tended to have lower creatinine clearance (p=0.10) and higher maximum plasma concentration of melphalan (p=0.07). CONCLUSION: OCT3 might be involved in melphalan transport in MM patients.