Six-month mortality has decreased for patients with curative treatment intent for head and neck cancer in Sweden.

BACKGROUND: In general, survival outcomes for patients with Head and Neck Cancer (HNC) has improved over recent decades. However, mortality within six months after diagnosis for curative patients remains at approximately 5%. The aim of this study was to identify risk factors for early death among patients with curative treatment, and furthermore, to analyze whether the risk of early death changed over recent years. MATERIAL AND METHOD: This real-world, population-based, nationwide study from the Swedish Head and Neck Cancer Register (SweHNCR) included all patients ≥18 years diagnosed with HNC with a curative treatment intent at the multidisciplinary tumor board from 2008 to 2020. A total of 16,786 patients were included. RESULTS: During the study period a total of 618 (3.7%) patients with curative-intended treatment died within six months of diagnosis. Patients diagnosed between 2008 and 2012 had a six-month mortality rate of 4.7% compared to 2.5% for patients diagnosed between 2017 and 2020, indicating a risk reduction of 53% (p <0.001) for death within six months. The mean time to radiation therapy from diagnosis in the 2008-2012 cohort was 38 days, compared to 22 days for the 2017-2020 cohort, (p <0.001). The mean time to surgery from diagnosis was 22 days in 2008-2012, compared to 15 days for the 2017-2020 cohort, (p <0.001). Females had a 20% lower risk of dying within six months compared to males (p = 0.013). For every year older the patient was at diagnosis, a 4.8% (p <0.001) higher risk of dying within six months was observed. Patients with a WHO score of 1 had approximately 2.4-times greater risk of early death compared to WHO 0 patients (p <0.001). The risk of early death among WHO 4 patients was almost 28 times higher than for WHO 0 patients (p <0.001). Patients with a hypopharyngeal tumor site had a 2.5-fold higher risk of dying within six months from diagnosis compared to oropharyngeal tumor patients (p <0.001). CONCLUSIONS: We found that the risk of early death decreased significantly from 2008 to 2020. During this period, the mean time to the start of treatment was significantly reduced both for surgery and oncological treatment regimes. Among patients with a curative treatment intention, increased risk of early death was associated with male sex, older age, advanced disease, increased WHO score, and a hypopharyngeal tumor site.

Pretreatment fat-free mass index correlates with early death in patients with head and neck squamous cell carcinoma.

BACKGROUND: A significant proportion of patients with head and neck squamous cell carcinoma (HNSCC) are malnourished at diagnosis. In this study, we investigated how pretreatment body mass index (BMI) and fat-free mass index (FFMI) correlate with early death, and whether these measurements are useful markers of prognosis for risk stratification of head and neck cancer patients. METHODS: Patients (n = 404) with newly diagnosed, curable HNSCC and WHO performance status 0-2 were prospectively included and met with a study representative before treatment initiation, as well as up to four follow-up visits. All patients provided an estimate of body weight at 6 months prior to diagnosis. Bioelectrical impedance analysis (BIA) was performed for all patients before treatment initiation. RESULTS: Most patients had oropharyngeal (46%), oral cavity (28%), or laryngeal cancer (12%). Forty-five (11%) patients met the standardized criteria for malnutrition according to the Global Leadership Initiative on Malnutrition (GLIM) at diagnosis. FFMI at diagnosis was lower in patients who died within 6 and 12 months after the start of treatment than in patients who survived these time points (p = 0.035 and p = 0.005, respectively). CONCLUSIONS: In this study, pretreatment FFMI was an independent prognostic factor for death within 6 and 12 months after the start of treatment in patients with HNSCC. Pretreatment BMI was not an independent risk factor for death within 6 and 12 months after treatment termination. Thus, FFMI may be useful for risk stratification of patients with head and neck cancer.

Base of tongue squamous cell carcinomas, outcome depending on treatment strategy and p16 status. A population-based study from the Swedish Head and Neck Cancer Register.

BACKGROUND: The base of tongue squamous cell carcinoma (BOTSCC) is mainly an HPV-related tumor. Radiotherapy (EBRT) ± concomitant chemotherapy (CT) is the backbone of the curatively intended treatment, with brachytherapy (BT) boost as an option. With four different treatment strategies in Sweden, a retrospective study based on the population-based Swedish Head and Neck Cancer Register (SweHNCR) was initiated. MATERIAL AND METHODS: Data on tumors, treatment and outcomes in patients with BOTSCC treated between 2008 and 2014 were validated through medical records and updated as needed. Data on p16 status were updated or completed with immunohistochemical analysis of archived tumor material. Tumors were reclassified according to the UICC 8th edition. RESULTS: Treatment was EBRT, EBRT + CT, EBRT + BT or EBRT + CT + BT in 151, 145, 82 and 167 patients respectively (n = 545). A p16 analysis was available in 414 cases; 338 were p16+ and 76 p16-. 5-year overall survival (OS) was 68% (95% CI: 64-72%), with76% and 37% for p16+ patients and p16- patients, respectively. An increase in OS was found with the addition of CT to EBRT for patients with p16+ tumors, stages II-III, but for patients with tumor stage I, p16+ (UICC 8) none of the treatment strategies was superior to EBRT alone. CONCLUSION: In the present retrospective population-based study of BOTSCC brachytherapy was found to be of no beneficial value in curatively intended treatment. An increase in survival was found for EBRT + CT compared to EBRT alone in patients with advanced cases, stages II and III (UICC 8), but none of the regimes was significantly superior to EBRT as a single treatment modality for stage I (UICC 8), provided there was p16 positivity in the tumor. In the small group of patients with p16- tumors, a poorer prognosis was found, but the small sample size did not allow any comparisons between different treatment strategies.

A national study of health-related quality of life in patients with cancer of the base of the tongue compared to the general population and to patients with tonsillar carcinoma.

BACKGROUND: This exploratory, registry-based, cross-sectional study aimed to evaluate patients' health-related quality of life (HRQOL) in a subsite of oropharyngeal cancer: cancer of the base of the tongue (CBT). METHODS: CBT patients, treated with curative intent, completed the EORTC QLQ-C30 and QLQ-H&N35 questionnaires 15 months after diagnosis. The HRQOL of CBT patients was compared to reference scores from the general population and to that of tonsillar carcinoma patients. RESULTS: The 190 CBT patients scored significantly worse than members of the general population on most scales. CBT patients with human papilloma virus (HPV)-positive tumors had significantly better HRQOL on 8 of 28 scales than HPV-negative patients. Compared to 405 tonsillar carcinoma patients, CBT patients had significantly worse HRQOL on 8 of the 28 scales, the majority local head and neck related problems. CONCLUSION: One year after treatment, CBT patients' HRQOL was significantly worse in many areas compared to that of the general population and slightly worse than that of tonsillar carcinoma patients.

A Nordic survey of the management of palliative care in patients with head and neck cancer.

BACKGROUND: The five Nordic countries with a population of 27M people form a rather homogenous region in terms of health care. The management of Head and Neck Cancer (HNC) is centralized to the 21 university hospitals in these countries. Our aim was to survey the current status of organization of palliative care for patients with HNC in the Nordic countries as the field is rapidly developing. MATERIALS AND METHODS: A structured web-based questionnaire was sent to all the Departments of Otorhinolaryngology-Head and Neck Surgery and Oncology managing HNC in the Nordic countries. RESULTS: All 21 (100%) Nordic university hospitals responded to the survey. A majority (over 90%) of the patients are discussed at diagnosis in a multidisciplinary tumor board (MDT), but the presence of a palliative care specialist is lacking in 95% of these MDT's. The patients have access to specialized palliative care units (n = 14, 67%), teams (n = 10, 48%), and consultants (n = 4, 19%) in the majority of the hospitals. CONCLUSION: The present results show that specialized palliative care services are available at the Nordic university hospitals. A major finding was that the collaboration between head and neck surgeons, oncologists and palliative care specialists is not well structured and the palliative care pathway of patients with HNC is not systematically organized. We suggest that early integrated palliative care needs to be included as an addition to the already existing HNC care pathways in the Nordic countries.

Health-related quality of life among tonsillar carcinoma patients in Sweden in relation to treatment and comparison with quality of life among the population.

BACKGROUND: The health-related quality of life (HRQOL) of tonsillar carcinoma survivors was explored to investigate any HRQOL differences associated with tumor stage and treatment. The survivors' HRQOL was also compared to reference scores from the population. METHODS: In this exploratory cross-sectional study patients were invited 15 months after their diagnosis and asked to answer two quality of life questionnaires (EORTC QLQ- C30, EORTC QLQ- HN35), 405 participated. RESULTS: HRQOL was associated with gender, with males scoring better than females on a few scales. Patients' HRQOL was more associated with treatment than tumor stage. Patients' HRQOL was worse than that in an age- and sex-matched reference group from the normal population, the largest differences were found for problems with dry mouth followed by problems with sticky saliva, senses, swallowing and appetite loss. CONCLUSIONS: The tonsillar carcinoma patients had a worse HRQOL compared to the general population one year after treatment.

Early mortality after diagnosis of cancer of the head and neck - A population-based nationwide study.

BACKGROUND: Cancers of the head and neck have a high mortality rate, and roughly 10% of the patients die within six months of diagnosis. To our knowledge little has been written about this group. We wished to identify risk factors for early death, to predict and monitor patients at risk better and, if possible, avoid unjustified major treatment. METHODS AND FINDINGS: This population-based nationwide study from the Swedish Head and Neck Cancer Register (SweHNCR) included data from 2008-2015 and 9733 patients at potential risk of early death. A total of 925 (9.5%) patients died within six months. For every year older the patients became, the risk of early death increased by 2.3% (p<0.001). The relative risk of death was 3.37 times higher (237%) for patients with WHO score 1 compared with WHO score 0. A primary tumour in the hypopharynx correlated with a 24% increased risk over the oral cavity (p<0.024). Patients with stage IV disease had a 3.7 times greater risk of early death than those with stage I (p<0.001). As expected, a 12 times increased risk of early death was noted in the palliative treatment group, compared to the curative group. Limitations to this study were that the actual cause of death was not recorded in the SweHNCR, and that socioeconomic factors, alcohol consumption, smoking habits, and HPV status, were not reported in SweHNCR until 2015. However, the fact that this is a population-based nationwide study including 9733 patients compensates for some of these limitations. CONCLUSIONS: Identification of patients at increased risk of early death shows that older patients with advanced disease, increased WHO score, primary tumour in the hypopharynx, and those given palliative treatment, are more likely than the others to die from head and neck cancer within six months of diagnosis.

Laryngo-tracheal resections in the Nordic countries: an option for further centralization?

PURPOSE: We aimed to obtain information on the number of Nordic centers performing tracheal resections, crico-tracheal resections, and laryngo-tracheal reconstructions, as well as the patient volume and the standard regimens associated with these procedures. METHODS: Consultants at all Departments of Otorhinolaryngology-Head and Neck Surgery (ORL-HNS, n = 22) and Thoracic Surgery (n = 21) in the five Nordic countries were invited (April 2018-January 2019) to participate in an online survey. RESULTS: All 43 departments responded to the survey. Twenty departments declared to perform one or more of the three types of tracheal resections. At five hospitals, departments of ORL-HNS and Thoracic Surgery perform these operations in collaboration. Hence, one or more of the tracheal operations in question are carried out at 15 centers. The median annual number of tracheal operations per center is five (range 1-20). Great variations were found regarding contraindications (relative and absolute) for surgery, the use of guardian sterno-mental sutures (all patients, 33%; selected cases, 40% of centers), prophylactic antibiotic therapy (cefuroxime +/- metronidazole, penicillin +/- metronidazole, clindamycin, imipenem, or none), post-operative follow-up time (range: children: 3-120 months; adults: 0-60 months), and the performance of post-operative bronchoscopy. CONCLUSIONS: Fifteen centers each perform a low number of annual operations with significant variations in the selection of patients and the clinical setup, which raises the question if a higher degree of collaboration and centralization would be warranted. We encourage Nordic transnational collaboration, pursuing alignment on central management issues, and establishment of a common prospective database for future tracheal resection surgery.

The effect of 2D and 3D cell cultures on treatment response, EMT profile and stem cell features in head and neck cancer.

BACKGROUND: Head and Neck Squamous Cell Carcinoma (HNSCC) tumors are often resistant to therapies. Therefore searching for predictive markers and new targets for treatment in clinically relevant in vitro tumor models is essential. Five HNSCC-derived cell lines were used to assess the effect of 3D culturing compared to 2D monolayers in terms of cell proliferation, response to anti-cancer therapy as well as expression of EMT and CSC genes. METHODS: The viability and proliferation capacity of HNSCC cells as well as induction of apoptosis in tumor spheroids cells after treatment was assessed by MTT assay, crystal violet- and TUNEL assay respectively. Expression of EMT and CSC markers was analyzed on mRNA (RT-qPCR) and protein (Western blot) level. RESULTS: We showed that HNSCC cells from different tumors formed spheroids that differed in size and density in regard to EMT-associated protein expression and culturing time. In all spheroids, an up regulation of CDH1, NANOG and SOX2 was observed in comparison to 2D but changes in the expression of EGFR and EMT markers varied among the cell lines. Moreover, most HNSCC cells grown in 3D showed decreased sensitivity to cisplatin and cetuximab (anti-EGFR) treatment. CONCLUSIONS: Taken together, our study points at notable differences between these two cellular systems in terms of EMT-associated gene expression profile and drug response. As the 3D cell cultures imitate the in vivo behaviour of neoplastic cells within the tumor, our study suggest that 3D culture model is superior to 2D monolayers in the search for new therapeutic targets.

Targeting aldehyde dehydrogenase activity in head and neck squamous cell carcinoma with a novel small molecule inhibitor.

Chemoresistant cancer cells express high levels of aldehyde dehydrogenases (ALDHs), particularly in head and neck squamous cell carcinoma (HNSCC). The ALDH family of enzymes detoxify both exogenous and endogenous aldehydes. Since many chemotherapeutic agents, such as cisplatin, result in the generation of cytotoxic aldehydes and oxidative stress, we hypothesized that cells expressing high levels of ALDH may be more chemoresistant due to their increased detoxifying capacity and that inhibitors of ALDHs may sensitize them to these drugs. Here, we show that overall ALDH activity is increased with cisplatin treatment of HNSCC and that ALDH3A1 protein expression is particularly enriched in cells treated with cisplatin. Activation of ALDH3A1 by a small molecule activator (Alda-89) increased survival of HNSCC cells treated with cisplatin. Conversely, treatment with a novel small molecule ALDH inhibitor (Aldi-6) resulted in a marked decrease in cell viability, and the combination of Aldi-6 and cisplatin resulted in a more pronounced reduction of cell viability and a greater reduction in tumor burden in vivo than what was observed with cisplatin alone. These data indicate that ALDH3A1 contributes to cisplatin resistance in HNSCC and that the targeting of ALDH, specifically, ALDH3A1, appears to be a promising strategy in this disease.

WRAP53ß, survivin and p16INK4a expression as potential predictors of radiotherapy/chemoradiotherapy response in T2N0-T3N0 glottic laryngeal cancer.

The current treatment recommendation for T2-3N0M0 glottic squamous cell carcinoma (SCC) in the Nordic countries comprises of radiotherapy (RT) and chemoradiotherapy (CRT). Tumor radiosensitivity varies and another option is primary surgical treatment, which underlines the need for predictive markers in this patient population. The aim of the present study was to investigate the relation of the proteins WRAP53ß, survivin and p16INK4a to RT/CRT response and ultimate outcome of patients with T2-T3N0 glottic SCC. Protein expression was determined using immunohistochemistry on tumors from 149 patients consecutively treated with RT or CRT at Helsinki University Hospital, Karolinska University Hospital, and Linköping University Hospital during 1999-2010. Our results demonstrate a significantly better 5-year relapse-free survival, disease-free survival (DFS), disease-specific survival and overall survival of patients with T3N0 tumors treated with CRT compared with RT alone. Patients with tumors showing a cytoplasmic staining of WRAP53ß revealed significantly worse DFS compared with those with nuclear staining. For survivin, we observed a trend towards better 5-year DFS in patients with strong nuclear survivin expression compared with those with weak nuclear survivin expression (p=0.091). Eleven (7%) tumors showed p16 positivity, with predilection to younger patients, and this age group of patients with p16-positive SCC had a significantly better DFS compared with patients with p16-negative SCC. Taken together, our results highlight WRAP53ß as a potential biomarker for predicting RT/CRT response in T2-T3N0 glottic SCC. p16 may identify a small but distinct group of glottic SCC with favorable outcome. Furthermore, for T3N0 patients better outcome was observed following CRT compared to RT alone.

Optimized Repopulation of Tendon Hydrogel: Synergistic Effects of Growth Factor Combinations and Adipose-Derived Stem Cells.

Background: Tendon-derived extracellular matrix (ECM) hydrogel has been shown to augment tendon healing in vivo. We hypothesized that reseeding of the gel with adipose-derived stem cells (ASCs) could further assist repopulation of the gel and that combinations of growth factors (GFs) would improve the survival of these cells after reseeding. Methods: A tendon-specific ECM solution was supplemented with varying concentrations of basic fibroblast growth factor (bFGF), insulin-like growth factor-1 (IGF-1), and platelet-derived growth factor-BB (PDGF-BB). Gels were then seeded with ASCs transfected with a green fluorescent protein/luciferin construct. Cell proliferation was determined using the MTT assay and histology, and GF and ASC augmented gels were injected into the back of Sprague Dawley rats. Bioluminescence of seeded gels was continuously followed after reseeding, and cell counts were performed after the gels were explanted at 14 days. Results: Synergistic effects of the GFs were seen, and an optimal combination was determined to be 10 ng/mL bFGF, 100 ng/mL IGF-1, and 100 ng/mL PDGF-BB (2.8-fold increase; P < .05). In vivo bioluminescence showed an improved initial survival of cells in gels supplemented with the optimal concentration of GF compared with the control group (10.6-fold increase at 8 days; P < .05). Cell counts of explants showed a dramatic endogenous repopulation of gels supplemented by GF + ASCs compared with both gels with GF but no ASCs (7.6-fold increase) and gels with ASCs but no GF (1.6-fold increase). Conclusion: Synergistic effects of GFs can be used to improve cellular proliferation of ASCs seeded to a tendon ECM gel. Reseeding with ASCs stimulates endogenous repopulation of the gel in vivo and may be used to further augment tendon healing.

A Nordic survey on the management of head and neck CUP.

CONCLUSION: The management of Head and Neck Cancer of Unknown Primary (HNCUP) patients varies both between centres within and also between the Nordic countries. This study contributes to a continuing discussion of how to improve the accuracy of diagnosis and quality of treatment of HNCUP patients. OBJECTIVES: The initiative for this study was based on the lack of common guidelines for diagnostic procedures and for treatment of HNCUP patients in the Nordic countries constituting a region having a rather homogeneous population. METHOD: A structured questionnaire was sent to all university hospitals in the five Nordic countries. RESULTS: Four of the five Nordic countries use either national guidelines or specific protocols when handling HNCUP. The main diagnostic tools are PET-CT, fine needle aspiration, endoscopic evaluation with biopsies, and most often bilateral tonsillectomy. At 21 of 22 university hospitals the treatment decision is made at a multidisciplinary conference. Three of seven Swedish centres use only radiotherapy or chemoradiotherapy to treat N+ HNCUP patients. Robotic surgery for biopsy of the tongue base is beginning to become an alternative to targeted biopsies in Sweden and Finland. Narrow Band Imaging is used only in Finland.

Early death among head and neck cancer patients.

PURPOSE OF REVIEW: Management of advanced head and neck cancer (HNC) is characterized by high mortality. Furthermore, the treatment involves significant burden to patients and high costs to healthcare systems. Recognizing the risks of early death in patients with a high probability of noncurable disease is important for each individual treatment decision-making. It is thus critical to consider the benefits and side-effects of the planned treatment in relation to the expected survival and to discuss these factors with the patient. However, only few studies have documented early death in HNC patients, that is, during the first posttreatment 6 months. We performed a systematic literature review to find the incidence of this phenomenon and to outline the probable cause. RECENT FINDINGS: Early mortality in patients with HNC can be explained either by direct effect of malignant disease, may be related to comorbidities, or secondary to the treatment. These factors act together resulting in expected or unexpected early death. SUMMARY: The present review provides information on the mechanisms leading to early phase mortality (<6 months) after management of HNC. It also reports the incidence of this phenomenon among Finnish and Swedish patient populations.

DNA repair genes XPC, XPD, XRCC1, and XRCC3 are associated with risk and survival of squamous cell carcinoma of the head and neck.

Head and neck squamous cell carcinomas (HNSCC) are a heterogenous group of tumors with a high rate of early recurrences, second primary tumors, and mortality. Despite advances in diagnosis and treatment over the past decades, the overall 5-year survival rate remains around 50%. Since the head-and neck-region is continuously exposed to potentially DNA-damaging exogenous and endogenous factors, it is reasonable to expect that the DNA repair genes play a part in the development, progression, and outcome of HNSCC. The aim of this study was to investigate the SNPs XPC A499V, XPD K751Q, XRCC1 R399Q, and XRCC3 T241M as potential risk factors and indicators of survival among Caucasian patients. One-hundred-sixty-nine patients as well as 344 healthy controls were included and genotyped with PCR-RFLP. We showed that XPC A499V was associated with increased risk of HNSCC, especially laryngeal carcinoma. Among women, XPD K751Q was associated with increased risk of oral SCC. Furthermore, XPD homozygous mutant individuals had the shortest survival time, a survival time that increased however after full dose radiotherapy. Wild-type individuals of XRCC3 T241M demonstrated an earlier age of onset. HPV-positive never smokers had lower frequencies of p53 mutation. Among HNSCC patients, HPV-positivity was significantly associated with XRCC1 R399Q homozygous mutant genotype. Moreover, combinations of putative risk alleles seemed to act synergistically, increasing the risk of HNSCC. In conclusion, our results suggest that SNPs of the DNA repair genes XPC, XPD, XRCC1, and XRCC3 may affect risk and survival of HNSCC.

Targeting Toll-like receptor 2 inhibits growth of head and neck squamous cell carcinoma.

Infection-driven inflammation has been proposed to be involved in the tumorigenesis of head and neck squamous cell carcinoma (HNSCC). Oral HNSCC is often colonized with microbes such as gram-positive bacteria and yeast, where ligands derived from their wall components have been shown to specifically bind to Toll-like receptor 2 (TLR2). Although TLR2 has been described to be expressed in oral HNSCC, its function has not been well characterized. Here, we show the expression of TLR2 in both HNSCC cell lines and primary patient-derived HNSCC xenograft tumors. Activation of TLR2 with a yeast-derived ligand of TLR2, zymosan, promoted organoid formation in an ex vivo model of tumor growth, while blockade with anti-TLR2 antibodies inhibited organoid formation. Zymosan also induced phosphorylation of ERK and the p65 subunit of NF-κB, which was inhibited in the presence of anti-TLR2 antibodies, indicating that this receptor is functional in HNSCC and that the signaling through these pathways is intact. TLR2 blockade also inhibited growth of human xenografted tumors in immunodeficient mice. In summary, our data show that TLR2 is a functional receptor expressed in human HNSCC that plays a direct pro-tumorigenic role, and that it can be therapeutically targeted with blocking antibodies to reduce tumor growth.

Nuclear expression of WRAP53ß is associated with a positive response to radiotherapy and improved overall survival in patients with head and neck squamous cell carcinoma.

OBJECTIVES: Today there are no reliable predictive markers for radiotherapy response in head and neck squamous cell carcinoma (HNSCC), leading to both under- and over-treatment of patients, personal suffering, and negative socioeconomic effects. Inherited mutation in WRAP53ß (WD40 encoding RNA Antisense to p53), a protein involved in intracellular trafficking, dramatically increases the risk of developing HNSCC. The purpose of this study was to investigate whether WRAP53ß can predict response to radiotherapy in patients with HNSCC. MATERIALS AND METHODS: Tumor biopsies from patients with HNSCC classified as responders or non-responders to radiotherapy were examined for the expression of the WRAP53ß protein and single nucleotide polymorphisms in the corresponding gene employing immunohistochemistry and allelic discrimination, respectively. In addition, the effect of RNAi-mediated downregulation of WRAP53ß on the intrinsic radiosensitivity of two HNSCC cell lines was assed using crystal violet and clonogenic assays. RESULTS: Nuclear expression of WRAP53ß was significantly associated with better response to radiotherapy and improved patient survival. Downregulation of WRAP53ß with siRNA in vitro enhanced cellular resistance to radiation. CONCLUSIONS: Our findings suggest that nuclear expression of WRAP53ß promotes tumor cell death in response to radiotherapy and is a promising predictor of radiotherapy response in patients with HNSCC.

CD271 is a functional and targetable marker of tumor-initiating cells in head and neck squamous cell carcinoma.

Tumor-initiating cells (TICs) in squamous cell carcinoma of the head and neck (SCCHN) are best characterized by their surface expression of CD44. Although there is great interest in identifying strategies to target this population, no marker of these cells has been found to be functionally active. Here, we examined the expression of the purported marker of normal human oral epithelial stem cells, CD271. We show that CD271 expression is restricted to a subset of the CD44+ cells. Using xenograft assays, we show that the CD44+CD271+ subpopulation contains the most tumorigenic cells. Loss of CD271 function results in a block in the G2-M phase of the cell cycle and a profound negative impact on the capacity of these cells to initiate tumor formation in vivo. Incubation with recombinant NGF results in enhanced phosphorylation of Erk, providing additional evidence that CD271 is functionally active. Finally, incubation of SCCHN cells with antibody to CD271 results in decreased Erk phosphorylation and decreased tumor formation in vivo. Thus, our data are the first to demonstrate that CD271 more specifically identifies the TIC subpopulation within the CD44+ compartment in SCCHN and that this receptor is a functionally active and targetable molecule.

Strong expression of survivin is associated with positive response to radiotherapy and improved overall survival in head and neck squamous cell carcinoma patients.

Head and neck squamous cell carcinoma (HNSCC) is a malignancy that is associated with severe mortality despite advances in therapy. Today's standard treatment most commonly includes radiotherapy, often combined with chemotherapy or surgery. There are so far no established biomarkers to predict response to radiation, and thus the aim of this study was to investigate a series of markers that could potentially identify HNSCC patients who would benefit from radiotherapy. The selected markers, both proteins (epidermal growth factor receptor, survivin and p53), and single nucleotide polymorphisms (SNPs) in the genes of XRCC3, XRCC1, XPC, XPD, MDM2, p53 and FGFR4 were correlated to the response to radiotherapy and overall survival. Investigations were performed on pretreatment tumor biopsies from patients classified as responders or nonresponders to radiotherapy. Protein expression was examined using immunohistochemistry and the genotyping of specific SNPs was analyzed using PCR-RFLP or pyrosequencing. We found that survivin expression was significantly stronger in the responder group (p = 0.003) and that patients with a strong survivin expression had a significantly better overall survival (p < 0.001). Moreover, downregulation of survivin by siRNA in two HNSCC cell lines significantly decreased their sensitivity to radiation. Among the SNPs analyzed, patients with the XPD Lys751Gln SNP had a significantly shorter overall survival (p = 0.048), and patients with the FGFR4 Gly388Arg SNP had a significantly longer overall survival (p = 0.010). In conclusion, our results suggest that survivin plays an important role in the response to radiotherapy and may be a useful marker for predicting radiotherapy response in patients with HNSCC.