Prospects for pluripotent stem cell therapies: into the clinic and back to the bench.

Pluripotent stem cells, embryonic stem (ES) cells and induced pluripotent stem (iPS) cells, both hold great promise for the understanding and treatment of disease. They can be used for drug testing, as in vitro models for human disease progression, and for transplantation therapies. Research in this area has been influenced by the ever-changing political landscape, particularly in the United States. In this review, we discuss the prospects for clinical application using pluripotent cells, focusing on an evaluation of iPS cell potential, the continuing concern of tumor formation, and a summary of in vitro differentiation protocols and animal models used. We also describe the current clinical trials underway in the United States, as well as the ups and downs of funding for ES cell work.

Teratocarcinosarcoma of the nasal cavity and paranasal sinuses: report of 3 cases with assessment for chromosome 12p status.

Sinonasal teratocarcinosarcoma (SNTCS) is a rare malignant neoplasm with 63 reported cases to date. Patients are exclusively adults, with a mean age of 60 years and marked male predominance. Histologically, these tumors are characterized by the presence of admixed epithelial and mesenchymal components. The histogenesis of SNTCS remains uncertain and genetic studies have not been reported to date. Two SNTCSs from the archives of Memorial Sloan-Kettering Cancer Center and one submitted from St Luke's-Roosevelt Hospital Center were evaluated by fluorescent in situ hybridization for amplification of chromosome12p, an event usually associated with the genesis of bona fide germ cell neoplasms (including mediastinal and testicular teratomas). Microscopic examination revealed admixed epithelial and mesenchymal elements in all 3 cases; benign squamous and glandular epithelium and neuroepithelial tissue were identified, the squamous epithelium demonstrating "fetal-like" cytoplasmic clearing. Mesenchymal proliferations were recognized ranging from well-differentiated smooth muscle to high-grade sarcoma. A malignant germ cell component was not identified in any of the cases. Fluorescent in situ hybridization evaluation demonstrated only 2 copies of chromosome 12 per case. Although the histogenesis of SNTCS remains uncertain, we have found an absence of 12p amplification in 3 cases. Our findings suggest that 12p amplification, if it occurs at all in this setting, is exceptional and that SNTCS is a somatic-type neoplasm exhibiting divergent differentiation rather than a germ cell tumor.

Cyanine fluorochrome-labeled antibodies in vivo: assessment of tumor imaging using Cy3, Cy5, Cy5.5, and Cy7.

Monoclonal antibodies to two different targetable antigens were conjugated to each of four commercially available cyanine fluorochromes. Equal amounts of all four antibodies were coinjected into tumor-bearing animals and imaged. Small, superficial tumors were adequately labeled using all four fluorochromes. Large tumors were labeled well only by Cy7, probably due to self-masking and dilution effects. Cy7 was superior to other cyanine fluorochromes for visualizing structures located deep within the animal.