What’s new in Pubmed this week: Stem Cells
Rabin N, Kyriakou C, Coulton L, Gallagher OM, Buckle C, Benjamin R, Singh N, Glassford J, Otsuki T, Nathwani AC, Croucher PI, Yong KL. A new xenograft model of myeloma bone disease demonstrating the efficacy of human mesenchymal stem cells expressing osteoprotegerin by lentiviral gene transfer. Leukemia. 2007 Oct;21(10):2181-91. Epub 2007 Jul 26. PMID: 17657224 Related Articles
Studies of multiple myeloma have always lacked a good animal model that recapitulates the bone lesions characteristic of the disease. Some models even go so far as to implant xenogenic bone, effectively doing in vivo cell culture. If the claims in the above paper hold up, they’ve solved this problem. The cell line KMS-12-BM appears to not invade any tissue besides bone to any great degree, extensively colonize the bone, skew the osteoblast/osteoclast ratio, and resorb trabecular bone. They’ve also tipped me off to a new and fantastic looking antibody for plasma cells. As a proof of principle, they transfect MSCs with Osteoprotegerin, a decoy receptor for RANK ligand, which results in lower recruitment of osteoclasts and a partial correction of the bone defect. Notably, the defect isn’t completely cured, which is consistent with our results indicating that there’s also a osteoblast defect, caused by Dkk1. Does anyone know if this cell line expresses DKK1? Also, please note that they appear to have mislabeled Figure 3d. The label, according to the text, should be osteoblast, not osteoclast. Hey, it’s not as bad as the osteosarcoma paper I presented in journal club last week1
Huang Z, Nelson ER, Smith RL, Goodman SB. The sequential expression profiles of growth factors from osteoprogenitors to osteoblasts in vitro. Tissue Eng. 2007 Sep;13(9):2311-20.
PMID: 17523879 Related Articles
This is a nice timestudy of the various factors produced by MSCs as they differentiate into osteoblasts.
My friends at the NIDCR have an article in Methods, discussing the assays available for testing stem cells. I mentioned in my previous post about the lack of a bioequivalence assay for stem cells, and I have to admit that I was simplifying things just a little. Their in vivo assay of MSCs is actually a functionally-relevant stem cell assay, but it’s just not something you can do on a routine basis for comparing two different isolation methods or culture conditions.
Lin VK, Wang SY, Vazquez DV, C Xu C, Zhang S, Tang L. Prostatic stromal cells derived from benign prostatic hyperplasia specimens possess stem cell like property. Prostate. 2007 Sep 1;67(12):1265-76. PMID: 17597114 Related Articles
Hameed M, Clarke K, Amer HZ, Mahmet K, Aisner S. Cellular angiofibroma is genetically similar to spindle cell lipoma: a case report. Cancer Genet Cytogenet. 2007 Sep;177(2):131-4. PMID: 17854668 Related Articles
Brown MD, Gilmore PE, Hart CA, Samuel JD, Ramani VA, George NJ, Clarke NW. Characterization of benign and malignant prostate epithelial Hoechst 33342 side populations. Prostate. 2007 Sep 15;67(13):1384-96. PMID: 17639507 Related Articles
The above articles all sound really interesting from the abstracts, but as I can’t read them because my library doesn’t have a subscription and they’re not open access, I can’t comment further.
Among many other serious mislabeling errors, they switched their GAPDH and gene of interest gel pictures and switched around two figures so that they made the opposite point from the text! It’s a shame, really, because it’s good work and in a high-impact journal. Here’s the link if you want to see for yourself.