Head and neck cancer (HNC) is one of the top ten cancers in the world, and is caused by tobacco use, alcohol consumption and Human Papillomavirus (HPV). HPV associated HNC patients have improved survival rates compared to non -HPV associated HNC patients. This improved survival is due to HPV- positive tumors favorable response to chemotherapy and radiation. The literature has shown that there is a racial disparity in survival rates between Caucasians and African Americans, with African Americans having poorer survival rates. The aim of this study is to determine if the racial disparity among HNC patients is due to a difference in HPV prevalence between races. HPV prevalence in HNC was assessed by a meta-analysis of published articles (30/247) that reported race specific HPV prevalence. We also conducted a pooled analysis in which authors that assessed HPV in HNC were invited to submit their datasets. Meta-pooled prevalence estimates revealed that 20% of African American HNC patients had HPV-positive tumors, compared to 44% in Caucasians. However for both African American HNC patients and Caucasian HNC patients there was low to moderate heterogeneity between the studies (Q-test p-value = p < 0.001, I2 = 18.87%, and p= 0.008. I2 =65.47% respectively). The prevalence of HPV in African Americans was 60% and in Caucasians it was 39%. African Americans had a risk of oropharyngeal cancer that was no different from Caucasians (OR: 1.38, 95% CI: 0.53-3.62) but had an increased risk of death from oropharyngeal cancer (HR: 2.39, 95% CI 1.03-5.55) compared to Caucasians. The results of the pooled analysis does not support the concept that African Americans HNC patients have a lower prevalence of HPV, but substantiates the notion that African Americans have worse survival than Caucasians. However, these are preliminary results as the pooled analysis is still being conducted, the inclusion of more datasets in the analysis could alter these preliminary findings. / Public Health

Objective: Existing patient-reported outcome measures (PROM)s for patients with facial differences lack content validity, as few items address appearance and function issues. The FACE-Q is a new PROM developed to measure outcomes important to patients aged 8-29 years with craniofacial conditions. A process was needed to determine if the FACE-Q content is relevant to patients with head and neck cancer (HNC). Methods: Cognitive interviews with patients with HNC aged 8 to 29 years (n=15) were conducted and feedback from experts in pediatric oncology (n=21) was obtained. Input was sought on all aspects of the FACE-Q content. Results: A total of 1573 codes were developed from patient comments and 234 codes were developed from expert feedback that related to the COSMIN criteria for judging content validity. A total of 12 items were flagged for review from qualitative interviews and 4 comments were coded from expert feedback among the core scales for comprehensibility. Instructions, time frame, and response options were found to be comprehensible and appropriate by almost all patient and expert participants. Participants identified a total of 10 missing items identified across the core scales, while no additional items were identified by experts for the core scales. However, 4 experts identified swallowing/dysphagia as an important item missing from the mouth function scale. Discussion: Content validity of the FACE-Q for patients with HNC was evaluated through cognitive interviews with patients and feedback from pediatric oncology experts. The core scales were answered by all participants and demonstrate overall content validity from feedback offered by both patients and experts. Conclusion: The FACE-Q showed evidence of content validity for its core scales along with limited evidence that the remaining scales covered issues relevant to specific HNC patients. Assessment of the psychometric properties of the new measure is forthcoming as part of an international FACE-Q field-test study. / Thesis / Master of Science (MSc) / The FACE-Q is a patient-reported outcome measure developed to assess outcomes important to patients aged 8-29 years with craniofacial conditions. The current study aimed to determine its content validity for use in patients with head and neck cancer (HNC). Cognitive interviews with patients with HNC aged 8-29 years (n=15) were conducted and feedback from experts in pediatric oncology (n=21) was obtained. A total of 1573 codes from patient comments and 234 codes from expert feedback were developed. A total of 12 items were flagged for review from qualitative interviews along with 4 items from expert feedback among the core scales for comprehensibility. Instructions and response options were found to be comprehensible and appropriate. A total of 10 missing items were identified across the core scales by patient participants while experts identified 1 missing item. The FACE-Q evidenced content validity for core scales along with limited evidence for remaining scales.

HNC incidence and mortality is greater in men and is associated with high risk behaviours and social deprivation. HNC is frequently diagnosed at advanced stages requiring multi-modality treatment which can have a significant impact on appearance and function. Gender can influence health behaviours yet research into male experiences of cancer has primarily focussed on prostate cancer and HNC is an area which is under investigated. The aim of this study was to explore how men with HNC experience appearance and functional change in the first 12 months following diagnosis. Grounded theory methodology (GT) was chosen as the overall purpose of GT is the generation of theory from the data which has explanatory power and advances the understanding of social and psychological phenomena. Retrospective semi-structured interviews were performed with 12 men who were 12 to 24 months post-diagnosis. Key components of GT practice used were simultaneous data collection and analysis, constructing analytic categories from the data, constant comparison, memo-writing and theoretical sampling. Three categories emerged from the data which were inter-related: normalising change; “under siege”: getting through treatment; and reclaiming self. The core category was reconciling change; a new normal which reflects the social and psychological processes involved in accommodating and assimilating change in appearance and function for men with HNC. The substantive theory provides insight into how men with HNC prioritise function and actively distance themselves from concerns regarding appearance. Furthermore, it identifies men who are at risk of social anxiety and isolation due to multiple changes or body incompetence. This study builds on theories of masculinity, body image and disfigurement. The substantive theory developed provides health and social care professionals with new knowledge to support clinical practice and improve care provision.

<p>Aim: The overall aim of this thesis was to acquire knowledge about daily life with focus on eating problems during the trajectory of care for patients with head and neck cancer treated with radiotherapy. Method: The data in study I were gained from medical and nursing records of 50 patients. Documented parameters of eating problems, their causes and consequences, and undertaken interventions were collected before treatment, during radiotherapy, and one, six, and twelve months after completion of treatment, using a study-specific audit instrument. Data were analysed with descriptive and inferential non-parametric statistics. In study II eight patients were interviewed during the radiotherapy treatment period with focus on experiences of eating problems. In study III nine patients were interviewed six to twelve weeks after treatment with the focus on experiences of daily life during the trajectory of care having eating problems. In study IV twelve patients were interviewed about their conceptions of the significance of a supportive nursing care clinic during the whole trajectory of care. Data were analysed with interpretative phenomenology (II, III) and phenomenography (IV). Findings: The four studies showed that being a patient in the trajectory of care often meant that life was disturbed and threatened. This was partly due to the eating problems and their consequences, which could occur during the whole trajectory of care (I, III, IV) but was experienced as most intense and severe during radiotherapy (II) and the nearest weeks after completion of radiotherapy (III, IV). The disturbances and threats experienced due to eating problems could affect the whole person as they were physical (I-IV), psychological, social and existential (II, III). The experiences of eating problems due to the tumour and its treatment and the experience of having cancer per se were strongly connected as one phenomenon, which disturbed and threatened the informants’ daily life. The other part that disturbed the patients’ life was the waiting in suspense. A long and trying waiting in uncertainty was experienced due to lack of knowledge and support, practical as well as emotional. This was most pronounced during pauses in radiotherapy (III) and after completion of the treatment when the lack of support from the health care was obvious (I, II, III). The patients were then most often left to their own devices. In order to endure, they needed both inner strength, described as own coping strategies, and strength from outside, described as support from family, friends and health care professionals (II, III). The nurse clinic was found to give a hand to hold during the whole trajectory of care (IV). It could meet these patients’ needs of knowledge, care and support, both concerning practical measures related to the eating problems and other side-effects of the treatment, and concerning their emotional needs. In addition the nurse clinic could support the relatives in their worries and anxiety (IV). Conclusion: This thesis showed the necessity of continuous assessment, treatment and evaluation of patients’ problems, and the patients’ needs of information and support throughout the trajectory of care.</p>

<p>Worldwide, head and neck squamous cell cancers (HNSCC) account for over 375,000 deaths annually. The majority of these cancers arise in the outermost squamous cells which progress through a series of precancerous changes before developing into invasive HNSCC. It is widely accepted that prognosis is strongly correlated to the stage of diagnosis, with early detection more than doubling the patient’s chance of survival. Currently, however, 60% of HNSCCs are diagnosed when they have already progressed to stage 3 or stage 4 disease. The current diagnostic method of visual examination often fails to recognize early indicators of HNSCC, thereby missing an important prevention window.</p><p> </p><p>Determination of cancer from non-malignant tissues is dependent on pathological examination of lesion biopsies. Thus, all patients with any clinically suspicious lesions undergo surgical biopsies. Furthermore, these surgical biopsies carry risks. In addition to the risk of general anesthesia for patients undergoing panedoscopy, some patients have poor healing and develop ulcerations or infections as a result of surgical biopsy at any anatomical site. Additionally, studies have shown that approximately 50% of suspected biopsies are later pathologically confirmed normal. An enormous amount of labor, facility, and monetary resources are expended on non-malignant biopsies and patients who ultimately have no malignancy. It would be of immense overall benefit to clinicians and patients to have a non-invasive and portable technique that could rapidly identify those patients that would benefit from further surgical biopsy from those that only need follow-up clinical observations.</p><p> </p><p>Once carcinoma is confirmed in a patient, treatment currently involves modalities of surgery, radiation, and chemotherapy. Radiotherapy plays a significant role, particularly in the management of localized HNSCC, because it is a non-invasive and function-preserving modality. However, the effectiveness of radiotherapy is limited by hypoxia. Previous studies showed that tumors reoxygenated during radiotherapy treatment may have a better prognosis. Despite decades of work, there is still no reliable, cost-effective way for measuring tumor hypoxia over multiple time points to estimate the prognosis. </p><p>To address these unmet clinical needs, three aims were proposed. The first aim was to improve early detection by identifying biomarkers of early pre-cancer as well as developing an objective algorithm to detect early disease. Neovasculature is an important biomarker for early cancer diagnosis. Even before the development of a clinically detectable lesion, the tumor vasculature undergoes structural and morphological changes in response to oncogenic signaling pathways [8]. Without receiving a sufficient supply of oxygen and nutrients to proliferate, early tumor growth is limited to only 1-2 mm. High-resolution optical imaging is well suited to characterize the earliest neovascularization changes that accompany neoplasia owing to its sensitivity to hemoglobin absorption and resolution to visualize capillary level architecture. Dark field microscopy is a low-cost and robust method to image the neovasculature. We imaged neovascularization in vivo in a spontaneous hamster oral mucosa carcinogen model using a label-free, reflected-light spectral dark field microscope. Hamsters’ cheek pouches were painted with 7, 12-Dimethylbenz[a]anthracene (DMBA) to induce precancerous to cancerous changes, or mineral oil as control. Spectral dark field images were obtained during carcinogenesis and in control oral mucosa, and quantitative vascular features were computed. Vascular tortuosity increased significantly in oral mucosa diagnosed as hyperplasia, dysplasia and squamous cell carcinoma (SCC) compared to normal. Vascular diameter and area fraction decreased significantly in dysplasia and SCC compared to normal. The areas under the receiver operative characteristic (ROC) curves (AUC) computed using a Support Vector Machine (SVM) were 0.95 and 0.84 for identifying SCC or dysplasia, respectively, vs. normal and hyperplasia oral mucosa combined. To improve AUCs for identifying dysplasia, quantitative vascular features were computed again after the vessels were split into large and small vessels based on diameter. The large vessels preserved the same significant trends, while small vessels demonstrated the opposite trends. Significant increases in diameter and decreases in area fraction were observed in SCC and dysplasia. The AUCs were improved to 0.99 and 0.92 for identifying SCC and dysplasia. These results suggest that dark field vascular imaging is a promising tool for pre-cancer detection.</p><p>Optical imaging can also be applied to quantifying other important characteristics of solid tumors in head and neck cancer (HNC), such as hypoxia, abnormal vascularity and cell proliferation. Diffuse reflectance spectroscopy is a simple and robust method to measure tissue oxygenation, vascularity and cell density. It is particularly suitable for applications in the operation room because of its compact design and portability. In addition, a fiber probe-based system is ideal for obtaining measurements at suspicious lesions in the head and neck area during surgery. Thus, my second aim was to reduce the number of unnecessary HNSCC biopsies by developing a robust tool and rapid analysis method appropriate for clinical settings. We propose the use of morphological optical biomarkers for rapid detection of human HNSCC by leveraging the underlying tissue characteristics in the aerodigestive tracts Prior to biopsy, diffuse reflectance spectra were obtained from malignant and contra-lateral non-malignant tissues of 57 patients undergoing panendoscopy. Oxygen saturation (SO2), total hemoglobin concentration ([THb]), and the reduced scattering coefficient were extracted using an inverse Monte Carlo (MC) method previously developed by former student in our lab. Differences in malignant and non-malignant tissues were examined based on two different groupings: by anatomical site and by morphological tissue type. Measurements were acquired from 252 sites, 51 of which were pathologically classified as SCC. Optical biomarkers exhibited statistical differences between malignant and non-malignant samples. Contrast was enhanced when parsing tissues by morphological classification rather than by anatomical subtype for unpaired comparisons. Corresponding linear discriminant models using multiple optical biomarkers showed improved predictive ability when accounting for morphological classification, particularly in node-positive lesions. The false-positive rate was retrospectively found to decrease by 34.2% in morphologically- vs. anatomically-derived predictive models. In glottic tissue, the surgeon exhibited a false-positive rate of 45.7% while the device showed a lower false-positive rate of only 12.4%. Additionally, comparisons of optical parameters were made to further understand the physiology of tumor staging and potential causes of high surgeon false-positive rates. Optical spectroscopy is a user-friendly, non-invasive tool capable of providing quantitative information to discriminate malignant from non-malignant head and neck tissues. Predictive models demonstrated promising results for diagnostics. Furthermore, the strategy described appears to be well suited to reduce the clinical false-positive rate.</p><p>To further improve the speed for extracting the tissue oxygenation and [THb] to reduce the time when patients were under anesthesia, the third aim was to develop a rapid heuristic ratiometric analysis for estimating tissue [THb] and SO2 from measured tissue diffuse reflectance spectra. The analysis was validated in tissue-mimicking phantoms and applied to clinical measurements in head and neck, cervical and breast tissues. The analysis works in two steps. First, a linear equation that translates the ratio of the diffuse reflectance spectra at 584 nm to 545 nm to estimate the tissue [THb] using a Monte carlo (MC)-based lookup table was developed. This equation is independent of tissue scattering and oxygen saturation. Second, SO2 was estimated using non-linear logistic equations that translate the ratio of the diffuse reflectance spectra at 539 nm to 545 nm into the tissue SO2. Correlations coefficients of 0.89 (0.86), 0.77 (0.71) and 0.69 (0.43) were obtained for the tissue hemoglobin concentration (oxygen saturation) values extracted using the full spectral MC and the ratiometric analysis, for clinical measurements in head and neck, breast and cervical tissues, respectively. The ratiometric analysis was more than 4000 times faster than the inverse MC analysis for estimating tissue [THb] and SO2 in simulated phantom experiments. In addition, the discriminatory power of the two analyses was similar. These results show the potential of such empirical tools to rapidly estimate tissue hemoglobin and oxygenation for real-time applications.</p><p>In addition to its use as a diagnostic marker for various cancers, tissue oxygenation is believed to play a role in the success of cancer therapies, particularly radiotherapy. However, since little effort has been made to develop tools to exploit this relationship, the fourth aim was to estimate patient prognosis by measuring tumor hypoxia over multiple time points so physicians are able to develop more informed and effective clinical treatment plan. To test if oxygenation kinetics correlates with the likelihood for local tumor control following fractionated radiotherapy, we again used diffuse reflectance spectroscopy to noninvasively measure tumor vascular oxygenation and [THb] associated with radiotherapy of 5 daily fractions (7.5, 9 or 13.5 Gy/day) in FaDu xenografts. Spectroscopy measurements were obtained immediately before each daily radiation fraction and during the week after radiotherapy. SO2 and [THb] were computed using an inverse MC model. Oxygenation kinetics during and after radiotherapy, but before a change in tumor volume, was associated with local tumor control. Locally controlled tumors exhibited significantly faster increases in oxygenation after radiotherapy (days 12-15) compared with tumors that recurred locally. (2) Within the group of tumors that recurred, faster increases in oxygenation during radiotherapy (days 3-5) were correlated with earlier recurrence times. An AUC of 0.74 was achieved when classifying the local control tumors from all irradiated tumors using the oxygen kinetics with a logistic regression model. (3) The rate of increase in oxygenation was radiation dose dependent. Radiation doses ≤9.5 Gy/day did not initiate an increase in oxygenation whereas 13.5 Gy/day triggered significant increases in oxygenation during and after radiotherapy. Additional confirmation is required in other tumor models, but these results suggest that monitoring tumor oxygenation kinetics could aid in the prediction of local tumor control after radiotherapy.</p><p>Angiogenesis is a highly regulated process to support tissue growth. Neovasculature is designed by nature to grow toward areas lacking nutrition and oxygen. Cancer cells proliferate too quickly to have their nutritional and oxygen needs completely satisfied, which results in an imbalanced state of angiogenesis leading to tortuous blood vessels, hypoxic tissues and radioresistance. We characterized the tumor-induced vascular features with simple, robust and low-cost dark field microscopy and spectroscopy to enable early cancer diagnosis, improvement of surgical biopsy accuracy and better predict the prognosis of radiotherapy for HNC. Our results demonstrated that these noninvasively measured, label-free vascular features are able to detect pre-cancer, reduce unnecessary surgical biopsies and predict prognosis of radiotherapy.</p> / Dissertation

INTRODUCTION: Head and neck cancer is one of the most common malignancy in the world. While it has been associated with several factors like alcohol consumption and smoking, there is approximately 25% of head and neck cancer that can be attributed to Human Papillomavirus (HPV) especially HPV 16. HPV associated cancer has been associated with a better prognosis as compared to HPV negative cancers. It has also been shown in previous studies that HPV-negative African Americans have a higher mortality rate as compared to HPV associated cancers in European Americans and HPV-negative European Americans patients. The three states of HPV associated cancers have been compared, which included HPV active, HPV inactive and HPV negative. AIM: The study aims include: 1) Compare the differences in the gene expression profiles of HPV negative HNSCC in AA from EA patients, and determine the differences in their biological make up. 2) Explore and compare the genetic expression profiles of HPV-active, HPV-inactive and HPV-negative head and neck cancer patients. METHODS: A secondary data analysis was conducted on 36 oropharyngeal cancer tissues samples with different HPV status (HPV-active, HPV-inactive and HPV- negative). ANOVA was conducted in R to compare all the three groups from each other and identify the genes that were differentially expressed. Bayes Moderated paired t-test was used to compare two groups of HPV-negative European Americans with HPV-negative African Americans. RESULTS: Our analysis revealed that the genes that were differentially expressed in HPV- active and HPV-negative analysis were different from HPV-active and HPV-inactive analysis. Our analysis also identified genes that were differentially expressed in African Americans as compared to European Americans. DISCUSSION: This study provides the genetic expression profiles in different groups (European Americans and African Americans) based on different HPV stages. Despite the small sample size of our data, we were able to identify the genes that were differentially expressed amongst different conditions in patients who had oropharyngeal carcinoma. We were also able to identify the genes involved in HPV-negative oral cancer comparing the African Americans to the European Americans.

Erst seit 2010 sind kombinierte Positronenemissionstomographie- Magnetresonanztomographie-Geräte (PET/MRT) zur hybriden Bildgebung verfügbar. Die mit der Entwicklung der Geräte verbundenen Hoffnungen bezüglich der onkologischen Diagnostik lagen zunächst auf einer verbesserten Genauigkeit in der Tumordetektion im Vergleich zur PET/CT. Rasch wurde jedoch deutlich, dass insbesondere die Möglichkeit der non-invasiven, multiparametrischen Charakterisierung von Tumorerkrankungen einen wesentlichen Vorteil der PET/MRT gegenüber der PET/CT darstellt. Der im Universitätsklinikum Leipzig AöR 2011 installierte PET/MRT-Scanner war einer der ersten weltweit und in dieser Habilitationsschrift sind die ersten Erfahrungen mit dieser Methode auf dem Gebiet der onkologischen Diagnostik zusammengefasst. Schwerpunkt ist dabei die Diagnostik von Kopf-Hals-Tumoren, da in diesem Bereich die CT aufgrund des im Vergleich zur MRT schlechteren Weichteilkontrastes Einschränkungen aufweist. In dieser Schrift werden zunächst die unterschiedlichen Konzepte im Gerätedesign der PET/MRT und die Besonderheiten der PET/MRT im Vergleich zur PET/CT erläutert. Auch die kritischen Punkte, die bei der Implementierung eines PET/MRT-Scanners zu beachten sind, werden detailliert dargestellt. Hierbei werden besonders die baulichen und organisatorischen Aspekte berücksichtigt, es werden aber auch Hinweise zur Qualitätskontrolle und zur Entwicklung von Untersuchungsprotokollen gegeben. In der ersten klinischen Studie zur Anwendung der PET/MRT mit 18F-Fluorodesoxyglucose (18F-FDG) bei Patienten mit Kopf-Hals-Tumoren konnten wir hinsichtlich Sensitivität und Spezifität noch keine Unterschiede zur PET/CT nachweisen. Allerdings war hier die untersuchte Patientengruppe heterogen und enthielt sowohl Primär- als auch Rezidivtumore. Aktuell konzentriert sich die onkologische Forschung am PET/MRT auf die Möglichkeiten der multiparametrischen Bildgebung zur Detektion und vor allem Charakterisierung von Tumorerkrankungen. Hier konnten wir signifikante Korrelationen von Glukosestoffwechsel und verschiedenen Perfusionsparametern bei Patienten mit Kopf-Hals-Tumoren nachweisen. Bei Patientinnen mit Zervixkarzinom konnte ein inverser Zusammenhang zwischen Glukosestoffwechsel und Diffusionsrestriktion nachgewiesen werden. Die letzte aufgeführte Arbeit zeigt die Korrelationen zwischen der bildgebenden Tumorcharakterisierung und histopathologischen Ergebnissen bei Kopf-Hals-Tumoren, wo wir Zusammenhänge von Kernfläche und dem Proliferationsmarker Ki-67 mit Diffusionseigenschaften bzw. Glukosestoffwechsel im Tumorgewebe nachweisen konnten.

The primary treatment options for head and neck cancer are radiation therapy or surgery, or both combined; chemotherapy is often used as an additional, or adjuvant, treatment. Patients treated with radiotherapy are exposed to a high cumulative dose of radiation over a period of time and there is a 17-33% chance of recurrence. High cumulative doses of radiation, a long time course of treatment, side effects and the possibility of recurrence provide the rationale for developing approaches for radiation sensitization, which could be helpful to patients in decreasing the dose, duration of radiation, side effects, or the chance of recurrence. Radiation induces autophagy, which is a catabolic process involving the degradation of the cell’s own components to generate energy under conditions of stress. Autophagy can be cytoprotective helping the cell to survive during stress such as nutrient deprivation or it can be cytotoxic, leading the cell toward death. We investigated whether blocking autophagy by the use of the antimalarial drug, chloroquine, could sensitize head and neck cancer cells to radiation. Studies were performed using the HN30 human head and neck cancer line (p53 wild type) derived from the pharynx as well as HN6 human cells (p53 mutant) derived from the base of the tongue. Cell viability was determined by cell counting and clonogenic survival assays, autophagy was monitored based on acridine orange staining accompanied by flow cytometry, while western blotting, DAPI and TUNEL staining and PI/annexin/FACS were utilized for determination and quantification of apoptosis. Senescence was monitored by beta-galactosidase staining/ FACS analysis. Radiation alone produced a transient growth arrest followed by proliferative recovery in both the HN30 and HN6 cancer cells. Radiation also promoted autophagy in both cell lines. The combination of chloroquine with radiation inhibited autophagy and promoted apoptotic cell death and suppression of proliferative recovery for the HN30 cells, but had little effect on sensitivity to radiation and proliferative recovery in the HN6 cells. The data suggest that autophagy induced by radiation serves a protective function in the HN30 cells and that a blockade to autophagy by chloroquine drives the cell toward apoptosis and death. In contrast, autophagy in HN6 cells appears to be non-protective as a pharmacological blockade did not sensitize the HN6 cells to radiation. These studies support the premise that autophagy induction by radiation need not necessarily have a cytoprotective function and further indicates that caution should be exercised in efforts to sensitize head and neck cancer to radiation through the clinical suppression of autophagy.

Head and neck squamous cell carcinoma is the 6th most common malignancyworldwide. Recently, a link between cancer and inflammation has been found. Mediatingthis relationship are the chemotactic cytokines known as chemokines. CXCL8 (Interleukin-8), a CXC ELR+ Chemokine mainly responsible for neutrophil chemoattraction, has beenimplicated in increased tumor proliferation, migration and angiogenesis. The current studytests the effects of CXCL8 on the tumor proliferation and metastasis. By genetically modifying cells to knockdown or overexpress the CXCL8 gene we tested its biological rolein head and neck cancer progression. Overexpression of CXCL8 in HN4 tumor cells withlow endogenous CXCL8 levels was found to increase tumor growth, as judged by cellcounting and MTT assays. Conversely, RNAi-mediated knockdown of CXCL8 expressionin HN12 cells, which express high levels of this chemokine, resulted in a decrease inproliferation. Similarly, overexpression of CXCL8 enhanced migration of HN4 cells invitro, while knockdown inhibited HN12 cell migration and invasion through a basementmembrane substitute. Taken together, these findings support the hypothesis that CXCL8affects multiple processes involved in head and neck cancer tumor progression. The datasuggest that CXCL8 is a potential therapeutic target for head and neck, and other, cancers.

Ao longo dos últimos anos, tornou-se evidente que o início e a progressão do câncer dependem de vários componentes do microambiente tumoral, incluindo células imunes e inflamatórias, fibroblastos, células endoteliais, adipócitos e matriz extracelular. Estes componentes e as células neoplásicas interagem entre si e trocam sinais pró e antitumor. O presente estudo teve como objetivo analisar o secretoma de células neoplásicas sob estresse e seu efeito no microambiente tumoral. Para este fim, duas linhagens celulares de carcinoma epidermóide de cabeça e pescoço foram cultivadas em duas condições de estresse: hipóxia e radiação. Os meios condicionados por estas células (secretoma 1) e o seu controle foram utilizados para cultivar células neoplásicas e fibroblastos humanos normais da cavidade oral. Os resultados sugerem que os sinais derivados das células neoplásicas em resposta a estresse dirigem a expressão gênica e proteica, bem como o comportamento celular das células vizinhas. Foram identificadas 38 proteínas celulares e nove proteínas secretadas com expressão aumentada e 61 proteínas celulares e 70 secretadas com expressão reduzida em células neoplásicas sob estresse hipóxico. Também foram identificadas 59 proteínas celulares e 29 proteínas secretadas com expressão aumentada e 59 proteínas celulares e 19 secretadas com expressão reduzida em células neoplásicas e fibroblastos humanos normais tratados com o meio condicionado por células sob estresse hipóxico. O secretome de células sob estresse não foi capaz de induzir proliferação de células neoplásicas e fibroblastos humanos normais, mas promoveu migração e invasão. Os resultados podem contribuir para o melhor entendimento do efeito dos fatores parácrinos liberados pelas células neoplásicas sobre a expressão gênica, bem como sobre o comportamento das células tumorais e estromais / Over the past years, it has become evident that cancer initiation and progression depends on several components of the tumor microenvironment, including inflammatory and immune cells, fibroblasts, endothelial cells, adipocytes, and extracellular matrix. These components and the neoplastic cells interact with each other providing pro and antitumor signals. The present study aimed to analyze the secretome of cancer cells under stress and their effect on the tumor microenvironment. For this purpose, two cell lines from head and neck carcinomas were cultured in two stress conditions - hypoxia and radiation. The medium conditioned by these cells (secretome 1) and their control were used to grow untreated neoplastic cells and normal human fibroblasts from oral cavity. Our results showed that signals derived from cancer cells in response to stress drive gene and protein expression and cell behavior. Thirty-eight overexpressed cellular and 9 secreted proteins, and 61 underexpressed cellular and 70 secreted proteins were identified in neoplastic cells under hypoxic stress. Fifty-nine overexpressed cellular and 29 secreted proteins, and 59 underexpressed cellular and 19 secreted proteins were identified in neoplastic cells and normal human fibroblasts treated with the medium conditioned by cells under hypoxic stress. The secretome of cells under stress was not able to induce proliferation of cancer cells and normal human fibroblasts, but promoted migration and invasion. The results may contribute to understand the effect of paracrine factors released by neoplastic cell on gene expression as well as on stromal and tumor cells behavior