Kawano Y, Fujiwara S, Wada N, Izaki M, Yuki H, Okuno Y, Iyama K, Yamasaki H, Sakai A, Mitsuya H, Hata H.

Multiple myeloma cells expressing low levels of CD138 have an immature phenotype and reduced sensitivity to lenalidomide.

Int J Oncol. 2012 Sep;41(3):876-84. doi: 10.3892/ijo.2012.1545. Epub 2012 Jul 4. PMID: 22766978; PMCID: PMC3582943.

https://pubmed.ncbi.nlm.nih.gov/22766978/