Purpose: The goal of this study was to examine the effect of tobacco use on disease recurrence (local/ regional recurrence, distant metastasis, or second primary) among patients with human papillomavirus (HPV)-positive squamous cell carcinoma of the oropharynx (SCCOP) following a complete response to chemoradiation therapy.Experimental Design: Between 1999 and 2007, 124 patients with advanced SCCOP (86% with stage IV) and adequate tumor tissue for HPV analysis who were enrolled in one of two consecutive University of Michigan treatment protocols were prospectively included in this study. Patients were categorized as never-, former, or current tobacco users. The primary end points were risk of disease recurrence and time to recurrence; secondary end points were disease-specific survival and overall survival.Results: One hundred and two patients (82.3%) had HPV-positive tumors. Over two thirds (68%) of patients with HPV-positive tumors were tobacco users. Among HPV-positive patients, current tobacco users were at significantly higher risk of disease recurrence than never-tobacco users (hazard ratio, 5.2; confidence interval, 1.1-24.4; P = 0.038). Thirty-five percent of HPV-positive ever tobacco users recurred compared with only 6% of HPV-positive never users and 50% of HPV-negative patients. All HPV-negative patients were tobacco users and had significantly shorter times to recurrence (P = 0.002), and had reduced disease-specific survival (P = 0.004) and overall survival (P < 0.001) compared with HPV-positive patients. Compared with HPV-positive never-tobacco users, those with a tobacco history showed a trend for reduced disease-specific survival (P = 0.064) but not overall survival (P = 0.221).Conclusions: Current tobacco users with advanced, HPV-positive SCCOP are at higher risk of disease recurrence compared with never-tobacco users. Clin Cancer Res; 16(4); 1226-35. ©2010 AACR.Head and neck squamous cell carcinoma is the eighth most common malignancy worldwide (1) and represents ∼5% of new cancer diagnoses worldwide annually (2). Over the past three decades, there has been a steady increase in the incidence of tonsil and tongue squamous cell carcinomas (3, 4). Recent evidence has identified high-risk human papillomavirus (HPV), particularly HPV-16, as a causative agent for a subset of head and neck squamous cell carcinomas, accounting for over 50% of squamous cell carcinomas of the oropharynx (SCCOP) in the United States (5-9). HPV-positive SCCOP has a distinct risk factor profile (6) and oncogenic mechanism (10, 11), and likely portends a more favorable prognosis than HPV-negative SCCOP (5,7,(12)(13)(14)(15)(16)(17). Despite its effect on prognosis, tumor HPV status has not yet been used to alter therapeutic management. The most popular current treatment for advanced SCCOP, regardless of HPV status, involves concurrent chemoradiation Authors' Affiliations:

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.

HHIP1 acts as a secreted Hedgehog antagonist whose association with heparan sulfate–containing basement membranes regulates Hedgehog ligand distribution.

Objectives Signal transducer and activator of transcription (STAT) proteins regulate key cellular fate decisions including proliferation and apoptosis. Over-expression of STAT3 induces tumor growth. We hypothesized that a novel small molecule inhibitor derived from curcumin (FLLL32) that targets STAT3 would induce cytotoxicity in STAT3 dependent HNSCC cells and would sensitize tumors to cisplatin. Design Basic science. Two HNSCC cell lines, UM-SCC-29 and -74B, were characterized for cisplatin sensitivity. Baseline expression of STAT3 and other apoptosis proteins was determined. The FLLL32 IC50 dose was determined for each cell line and the effect of FLLL32 treatment on the expression of phosphorylated STAT3 and other key proteins was elucidated. The anti-tumor efficacy of cisplatin, FLLL32 and combination treatment was measured. The proportion of apoptotic cells after cisplatin, FLLL32 or combination therapy was determined. Results The UM-SCC-29 cell line is cisplatin resistant and the UM-SCC-74B cell line is sensitive. Both cell lines express STAT3, phosphorylated STAT3 (pSTAT3) and key apoptotic proteins. FLLL32 downregulates the active form of STAT3, pSTAT3, in HNSCC cells and induces a potent anti-tumor effect. FLLL32, alone or with cisplatin, increases the proportion of apoptotic cells. FLLL32 sensitized cisplatin resistant cancer cells, achieving an equivalent tumor kill with a four-fold lower dose of cisplatin. Conclusions FLLL32 monotherapy induces a potent anti-tumor effect and sensitizes cancer cells to cisplatin, permitting an equivalent or improved anti-tumor effect at lower doses of cisplatin. Our results suggest that FLLL32 acts by inhibiting STAT3 phosphorylation, reduced survival signaling, increased susceptibility to apoptosis, and sensitization to cisplatin.