Background. In accord with the cancer stem cell (CSC) theory, only a small subset of cancer cells are capable of forming tumors. We previously reported that CD44 isolates tumorigenic cells from head and neck squamous cell cancer (HNSCC). Recent studies indicate that aldehyde dehydrogenase (ALDH) activity may represent a more specific marker of CSCs.Methods. 1 Despite advances in therapy that have improved quality of life, survival rates have remained static for many years. Mortality from this disease remains high because of the development of distant metastasis and the emergence of treatment-resistant local and regional recurrences. To develop more effective therapies for head and neck squamous cell cancer (HNSCC), it is essential that we gain a deeper understanding of the biology Correspondence to: M. E. Prince

Objective Subpopulations of highly tumorigenic cells, which have the unique capacity to self-renew and produce differentiated progeny, have been identified in multiple malignancies. In head and neck squamous cell carcinoma (HNSCC), this subpopulation of cells, termed cancer stem cells (CSCs) are contained within the population with high CD44 expression. It has been postulated that CSCs play a role in invasion and metastasis; however, there is little evidence to support this theory. We designed in vitro and in vivo models of metastasis to study the behavior of CSCs in HNSCC. Design Cells were sorted for CD44 expression using flow cytometry. Sorted cells were used in an in vitro invasion assay. For in vivo studies, CSCs and non-CSCs were injected into the tail veins of mice, and lungs were either harvested or imaged to evaluate for metastases. Results In vitro, CD44high cells were more motile but less invasive than CD44low cells. In vivo, 4/5 mice injected with CD44high cells and 0/5 mice injected with CD44low cells formed lung metastases. Two of the metastases arose from CSCs from a primary tumor and three from CSCs from HNSCC cell lines. Conclusions In vitro, CSCs do not have an increased ability to invade through basement membrane, but they do migrate more efficiently through a porous barrier. In contrast, CSCs formed metastases quite efficiently in vivo, whereas non-CSCs did not form metastases at all. This phenomenon could be due to enhanced migratory capacity of CSCs, which may be more important than basement membrane degradation in vivo.

BACKGROUND Few human papillomavirus (HPV)-positive head and neck squamous cell carcinoma (HNSCC) cell lines exist. We established UM-SCC-104, a new HPV(+) HNSCC cell linefrom a recurrent oral cavity tumor, and characterized it for the presence of cancer stem cells (CSC). METHODS Tumor cells were tested for biomarker expression by immunohistology and the presence of HPV was assessed by several methods. RESULTS UM-SCC-104 has a unique genotype, contains HPV-16 and expresses E6/E7. Inoculation of (Aldehyde Dehydrogenase) ALDH(+) and ALDH(−) cells in an immunocompromised mouse resulted in tumor growth from the ALDH(+) cells after 6 weeks that recapitulated the histology of the primary, while ALDH(−) cells did not produce tumors. CONCLUSIONS UM-SCC-104, a new HPV-16, CSC-containing HNSCC cell line will aid in studying recurrent HPV(+) tumors. The aggressive nature of this tumor is consistent with high uniform expression of EGFR and a functionally significant proportion of ALDH(+) CSC.

With recent advances in molecular techniques, collecting blood from birds has become a common practice among field ornithologists. There are a variety of techniques for collecting blood samples and numerous caveats for how samples should be processed, depending on the research question being asked. Currently, few resources are available for individuals learning how to collect blood from birds or needing more information about how to process blood samples. Here, I describe commonly used methods for collecting, processing, and storing blood for particular research objectives, and provide answers to frequently asked questions about blood collection. The information provided is intended primarily for investigators working with passerines, but many techniques and suggestions are applicable to other avian taxa.

Whereas migrating birds have been implicated in the spread of West Nile virus (WNV), there is no direct evidence of birds actively migrating while infectious. The role of birds in WNV dispersal is difficult to assess in the field. However, this role can be evaluated experimentally because birds in migratory disposition display increased locomotor activity or restlessness under captive conditions. We tested the following hypotheses: (1) migrating passerine birds continue to exhibit migratory activity while infectious with WNV and(2) the migratory state of the individual affects the magnitude of viremia. We examined the migratory activity of two neoarctic-neotropical passerine migrants, SwainsonÕs thrush (Catharus ustulatus) and gray catbird (Dumetella carolinensis), during acute WNV infection. All gray catbirds and six of nine SwainsonÕs thrushes exhibited migratory activity while infectious. Moreover, migratory status did not appear to influence viremia titers, as might be expected if individuals were immunosuppressed during migration. Therefore, we demonstrate that migrating passerine birds are potential dispersal vehicles for WNV.