(Hyperlinks to references in text)

(1)       Carvalho AL, Nishimoto IN, Califano JA, Kowalski LP. Trends in incidence and prognosis for head and neck cancer in the United States: a site-specific analysis of the SEER database. Int J Cancer 2005;114:806-16.

(2)       Sjogren EV, Wiggenraad RG, Le Cessie S, Snijder S, Pomp J, de Jong RJ. Outcome of radiotherapy in T1 glottic carcinoma: a population-based study. Eur Arch Otorhinolaryngol 2009;266:735-44.

(3)       Dirven R, Swinson BD, Gao K, Clark JR. The assessment of pharyngocutaneous fistula rate in patients treated primarily with definitive radiotherapy followed by salvage surgery of the larynx and hypopharynx. Laryngoscope 2009;119:1691-5.

(4)       Franchin G, Minatel E, Gobitti C, Talamini R, Vaccher E, Sartor G et al. Radiotherapy for patients with early-stage glottic carcinoma: univariate and multivariate analyses in a group of consecutive, unselected patients. Cancer 2003;98:765-72.

(5)       Rosenthal DI, Ang KK. Altered radiation therapy fractionation, chemoradiation, and patient selection for the treatment of head and neck squamous carcinoma. Semin Radiat Oncol 2004;14:153-66.

(6)       Groome PA, Schulze K, Boysen M, Hall SF, Mackillop WJ, O’Sullivan B et al. A comparison of published head and neck stage groupings in laryngeal cancer using data from two countries. J Clin Epidemiol 2002;55:533-44.

(7)       Bjork-Eriksson T, West C, Karlsson E, Mercke C. Tumor radiosensitivity (SF2) is a prognostic factor for local control in head and neck cancers. Int J Radiat Oncol Biol Phys 2000;46:13-9.

(8)       Janssen HL, Haustermans KM, Balm AJ, Begg AC. Hypoxia in head and neck cancer: how much, how important? Head Neck 2005;27:622-38.

(9)       Kim JJ, Tannock IF. Repopulation of cancer cells during therapy: an important cause of treatment failure. Nat Rev Cancer 2005;5:516-25.

(10)     Wildeman MA, Gibcus JH, Hauptmann M, Begg AC, van Velthuysen ML, Hoebers FJ et al. Radiotherapy in laryngeal carcinoma: can a panel of 13 markers predict response? Laryngoscope 2009;119:316-22.

(11)     Buffa FM, Bentzen SM, Daley FM, Dische S, Saunders MI, Richman PI et al. Molecular marker profiles predict locoregional control of head and neck squamous cell carcinoma in a randomized trial of continuous hyperfractionated accelerated radiotherapy. Clin Cancer Res 2004;10:3745-54.

(12)     Koukourakis MI, Giatromanolaki A, Danielidis V, Sivridis E. Hypoxia inducible factor (HIF1alpha and HIF2alpha) and carbonic anhydrase 9 (CA9) expression and response of head-neck cancer to hypofractionated and accelerated radiotherapy. Int J Radiat Biol 2007;1-6.

(13)     Winter SC, Buffa FM, Silva P, Miller C, Valentine HR, Turley H et al. Relation of a hypoxia metagene derived from head and neck cancer to prognosis of multiple cancers. Cancer Res 2007;67:3441-9.

(14)     Chi JT, Wang Z, Nuyten DS, Rodriguez EH, Schaner ME, Salim A et al. Gene expression programs in response to hypoxia: cell type specificity and prognostic significance in human cancers. PLoS Med 2006;3:e47.

(15)     Ishigami T, Uzawa K, Higo M, Nomura H, Saito K, Kato Y et al. Genes and molecular pathways related to radioresistance of oral squamous cell carcinoma cells. Int J Cancer 2007;120:2262-70.

(16)     Torres-Roca JF, Eschrich S, Zhao H, Bloom G, Sung J, McCarthy S et al. Prediction of radiation sensitivity using a gene expression classifier. Cancer Res 2005;65:7169-76.

            (17)     Amundson SA, Do KT, Vinikoor LC, Lee RA, Koch-Paiz CA, Ahn J et al. Integrating global gene expression and radiation survival parameters across the 60 cell lines of the National Cancer Institute Anticancer Drug Screen. Cancer Res 2008;68:415-24.

            (18)     Starmans MH, Krishnapuram B, Steck H, Horlings H, Nuyten DS, van de Vijver MJ et al. Robust prognostic value of a knowledge-based proliferation signature across large patient microarray studies spanning different cancer types. Br J Cancer 2008;99:1884-90.

            (19)     Baumann M, Krause M, Thames H, Trott K, Zips D. Cancer stem cells and radiotherapy. Int J Radiat Biol 2009;85:391-402.

            (20)     Baumann M, Krause M, Hill R. Exploring the role of cancer stem cells in radioresistance. Nat Rev Cancer 2008;8:545-54.

            (21)     Dumur CI, Ladd AC, Wright HV, Penberthy LT, Wilkinson DS, Powers CN et al. Genes involved in radiation therapy response in head and neck cancers. Laryngoscope 2009;119:91-101.

            (22)     Chung CH, Parker JS, Karaca G, Wu J, Funkhouser WK, Moore D et al. Molecular classification of head and neck squamous cell carcinomas using patterns of gene expression. Cancer Cell 2004;5:489-500.

            (23)     Chung CH, Parker JS, Ely K, Carter J, Yi Y, Murphy BA et al. Gene expression profiles identify epithelial-to-mesenchymal transition and activation of nuclear factor-kappaB signaling as characteristics of a high-risk head and neck squamous cell carcinoma. Cancer Res 2006;66:8210-8.

            (24)     Lohavanichbutr P, Houck J, Fan W, Yueh B, Mendez E, Futran N et al. Genomewide gene expression profiles of HPV-positive and HPV-negative oropharyngeal cancer: potential implications for treatment choices. Arch Otolaryngol Head Neck Surg 2009;135:180-8.

            (25)     Pramana J, van den Brekel MW, van Velthuysen ML, Wessels LF, Nuyten DS, Hofland I et al. Gene expression profiling to predict outcome after chemoradiation in head and neck cancer. Int J Radiat Oncol Biol Phys 2007;69:1544-52.

            (26)     Slebos RJ, Yi Y, Ely K, Carter J, Evjen A, Zhang X et al. Gene expression differences associated with human papillomavirus status in head and neck squamous cell carcinoma. Clin Cancer Res 2006;12:701-9.

            (27)     Lin SM, Du P, Huber W, Kibbe WA. Model-based variance-stabilizing transformation for Illumina microarray data. Nucleic Acids Res 2008;36:e11.

            (28)     Du P, Kibbe WA, Lin SM. lumi: a pipeline for processing Illumina microarray. Bioinformatics 2008;24:1547-8.

            (29)     R Development Core Team (2008). R: A language and environment for statistical computing. Vienna, Austria: R Foundation for Statistical Computing; 2009.

            (30)     Amundson SA, Grace MB, McLeland CB, Epperly MW, Yeager A, Zhan Q et al. Human in vivo radiation-induced biomarkers: gene expression changes in radiotherapy patients. Cancer Res 2004;64:6368-71.

            (31)     Prince ME, Sivanandan R, Kaczorowski A, Wolf GT, Kaplan MJ, Dalerba P et al. Identification of a subpopulation of cells with cancer stem cell properties in head and neck squamous cell carcinoma. Proc Natl Acad Sci U S A 2007;104:973-8.

            (32)     Grenman R, Burk D, Virolainen E, Wagner JG, Lichter AS, Carey TE. Radiosensitivity of head and neck cancer cells in vitro. A 96-well plate clonogenic cell assay for squamous cell carcinoma. Arch Otolaryngol Head Neck Surg 1988;114:427-31.

            (33)     Grenman R, Burk D, Virolainen E, Buick RN, Church J, Schwartz DR et al. Clonogenic cell assay for anchorage-dependent squamous carcinoma cell lines using limiting dilution. Int J Cancer 1989;44:131-6.

            (34)     Grenman R, Carey TE, McClatchey KD, Wagner JG, Pekkola-Heino K, Schwartz DR et al. In vitro radiation resistance among cell lines established from patients with squamous cell carcinoma of the head and neck. Cancer 1991;67:2741-7.

            (35)     Kawano T, Nakamura Y, Yanoma S, Kubota A, Furukawa M, Miyagi Y et al. Expression of E-cadherin, and CD44s and CD44v6 and its association with prognosis in head and neck cancer. Auris Nasus Larynx 2004;31:35-41.

            (36)     Zhao H, Ren J, Zhuo X, Ye H, Zou J, Liu S. Prognostic significance of Survivin and CD44v6 in laryngeal cancer surgical margins. J Cancer Res Clin Oncol 2008;134:1051-8.

            (37)     Wang SJ, Wong G, de Heer AM, Xia W, Bourguignon LY. CD44 variant isoforms in head and neck squamous cell carcinoma progression. Laryngoscope 2009;119:1518-30.

            (38)     Mack B, Gires O. CD44s and CD44v6 expression in head and neck epithelia. PLoS One 2008;3:e3360.

            (39)     Ponta H, Sherman L, Herrlich PA. CD44: from adhesion molecules to signalling regulators. Nat Rev Mol Cell Biol 2003;4:33-45.

            (40)     Martinive P, Defresne F, Bouzin C, Saliez J, Lair F, Gregoire V et al. Preconditioning of the tumor vasculature and tumor cells by intermittent hypoxia: implications for anticancer therapies. Cancer Res 2006;66:11736-44.

            (41)     Seigneuric R, Starmans MH, Fung G, Krishnapuram B, Nuyten DS, van Erk A et al. Impact of supervised gene signatures of early hypoxia on patient survival. Radiother Oncol 2007;83:374-82.

            (42)     Addla SK, Brown MD, Hart CA, Ramani VA, Clarke NW. Characterization of the Hoechst 33342 side population from normal and malignant human renal epithelial cells. Am J Physiol Renal Physiol 2008;295:F680-F687.

            (43)     Hill RP, Milas L. The proportion of stem cells in murine tumors. Int J Radiat Oncol Biol Phys 1989;16:513-8.

            (44)     Ma S, Chan KW, Hu L, Lee TK, Wo JY, Ng IO et al. Identification and characterization of tumorigenic liver cancer stem/progenitor cells. Gastroenterology 2007;132:2542-56.

            (45)     Glinsky GV, Berezovska O, Glinskii AB. Microarray analysis identifies a death-from-cancer signature predicting therapy failure in patients with multiple types of cancer. J Clin Invest 2005;115:1503-21.