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Organ‐transplant recipients (OTRs) on a new class of immunosuppressants, rapamycin and its analogues, have reduced cutaneous Squamous Cell Carcinomas (cSCCs). Rapamycin, an mTORC1 inhibitor, is also a known autophagy inducer in experimental models. Autophagy, which literally means self‐eating, is a cell survival mechanism but can also lead to cell death. Therefore, the main hypothesis behind this work is that rapamycin prevents epidermal tumourigenesis by either affecting epidermal mTOR regulation of autophagy and/or selectively affecting epidermal AKT isoform activity. Epidermal keratinocytes move from the proliferating basal layer upwards to the granular layers where they terminally differentiate, forming a layer of flattened, anucleate cells or squames of the cornified layer which provides an essential environmental barrier. However, epidermal terminal differentiation, a specialised form of cell death involving organelle degradation, is poorly understood. The work presented in this thesis shows that analysis of the autophagy marker expression profile during foetal epidermal development, indicates autophagy is constitutively active in the terminally differentiating granular layer of epidermis. Therefore, I hypothesize that autophagy is a mechanism of organelle degradation during terminal differentiation of granular layer keratinocytes. In monolayer keratinocytes, activation of terminal differentiation is accompanied by autophagic degradation of nuclear material, nucleophagy. This suggests that constitutive autophagy is a pro‐death mechanism required for terminal differentiation. In cultured keratinocytes and in epidermal cultures, rapamycinmediated mTORC1 inhibition strongly increases AKT1 activity as well as up‐regulates constitutive granular layer autophagy promoting terminal differentiation. Therefore, autophagy is an important fundamental process in keratinocytes which may be the mechanism by which terminally differentiating keratinocytes of the epidermal granular layer degrade their organelles required for barrier formation. This may have implications for the treatment of patients with barrier defects like psoriasis. In immunosuppressed OTRs, rapamycin may promote epidermal autophagy and AKT1 activity adding to its anti‐tumourigenic properties.

AIM & OBJECTIVES: Human papilloma virus (HPV) has been related to cervical infection, however, its part in Head and Neck Squamous Cell Carcinoma (HNSCC) is still debatable and is easy to refute. Suspicion of HPV causation is heightened when carcinomas arise in patients that are young and have never smoked. The present UK based study undertaken at Northampton NHS Trust endeavoured to determine the extent to which HPV is an entity in HNSCC in the UK. Furthermore, the study investigated whether sexual behaviour (as measured by sexual health clinic (SHC) attendance) is linked the acquisition of HPV associated HNSCC in young age groups. HNSCC incidences and sexual trends in the UK were collected from publicly available databases to identify if there were any changes at a national level in sexual behaviours and their influence on HNSCC in young age groups. MATERIALS & METHODS: PCR was used to evaluate the presence of HPV in biopsy samples from of 99 patients diagnosed with HNSCC at Northampton Hospital from 2006 to 2014. Patient demographics on age, sex, smoking, alcohol use and SHC attendance were also collected. All HPV PCR positive biopsies were further genotyped using an ABI 3130xl genetic analyser. Databases in the UK; including GLOBOCAN, NATSAL and PHE were searched for data on HNSCC prevalence, sexual behaviour trends and vaccine uptake. Multinomial regression explored the relationship between HPV positivity and sex, age, smoking, drinking, race and SHC attendance. RESULTS: PCR showed that 25.2% (25/99) of biopsies tested were positive for HPV and were all obtained from white participants. Most specimens (23, 92%) were high-risk (HR) HPV 16 positive with a mean age of 56 for HPV positivity and 72% of the cases 50-60 years old. Smokers were 11% in total (11/99) with most 88.9% participants (88/99) being non-smokers. HPV positivity was strongly linked with non-smoking history (p < 0.001); no alcohol abuse (p < 0.001); male gender (p < 0.001); young age less than 60 years (p < 0.001) and SHC attendance (p < 0.001). A Kruskal-Wallis post hoc test affirmed the impact of age on HPV positivity (p= < 0.05). GLOBOCAN and Cancer Research demonstrated a rising UK HNSCC pattern of over 200% for both sexes from 1975 to 2011. The three NATSAL surveys undertaken in 1990-1991, 1999-2001 and 2010-2012 demonstrated an overall increase in opposite and same sex partners. The UK average of individuals engaging in oral sex was in the younger age groups of between 16 and 54 with at least 70% of males and 63% females of that age engaging in oral sex. Finally, NASTAL 1, 2 and 3 surveys reported 20 vs 15; 25 vs 55; 55 vs 65 of males and females respectively with more than 10 sexual partners to have attended the SHC. The UK immunization take-up was over 90% countrywide. CONCLUSION: Few research studies have been conducted to date on HPV as a cause of HNSCC in the UK. The present research showed 25.2% of HNSCC to be caused by HPV, with the high risk (HR) genotype 16 (the leading cause of cervical cancer) accounting for 92% (23/25) of the cases. These outcomes affirmed the high prevalence of HR-HPV in HNSCC, with a rate of 25.2% similar to those reported previously. Routine HPV testing in those aged below 60 is therefore warranted. Smoking and drinking showed negative correlation; the young age of below 60 and attendance of the SHC for both sexes showed a positive correlation with HPV positive HNSCC. NATSAL data showed increased sexually risky behaviour coupled with attending the SHC in younger ages for both sexes. Increased sexually risky behaviour as shown in NASTAL surveys may be the reason why young age and SHC attendance is positively correlated with HPV HNSCC. The study highlights a conceivable relationship between HPV positive HNSCC in those under 60 years with no smoking history who attended the SHC. Smoking and drinking are known risks for HNSCC in those past 65 years of age; the negative association with HPV HNSCC in the young in the present research revealed smoking and drinking to have reduced association with HPV HNSCC. The reported HR-HPV positive HNSCC in young age groups inform future vaccination strategies and consequently decrease the quantity of HPV HNSCC's.

Submitted by Ana Maria Fiscina Sampaio (fiscina@bahia.fiocruz.br) on 2013-10-18T17:47:47Z No. of bitstreams: 1 Danniel Sann Dias da Silva Analise da ancestralidade...2013.pdf: 1290114 bytes, checksum: 95da03014304e202e3b248867ec987a7 (MD5) / Made available in DSpace on 2013-10-18T17:47:47Z (GMT). No. of bitstreams: 1 Danniel Sann Dias da Silva Analise da ancestralidade...2013.pdf: 1290114 bytes, checksum: 95da03014304e202e3b248867ec987a7 (MD5) Previous issue date: 2013 / Fundação Oswaldo Cruz. Centro de Pesquisas Gonçalo Moniz. Salvador, BA, Brasil / O carcinoma escamocelular oral (CEO), entre homens, é o quarto câncer mais frequente no Nordeste do Brasil e o terceiro na Bahia. Apesar de possuir etiologia multifatorial, pelo menos 80% dos casos são atribuíveis à exposição ao fumo e ao álcool. Suscetibilidade individual ao CEO tem sido amplamente estudada, e é atribuída a fatores genéticos e também sócio-econômicos. Polimorfismos genéticos de risco, comuns em determinadas populações; hábitos de vida; dificuldade de acesso à informação e aos serviços de saúde são exemplos destes fatores. Sabendo da alta incidência do CEO na Bahia objetivou-se analisar a distribuição dos fatores de risco para CEO numa amostra da população da Bahia. Participaram 332 doadores voluntários de um banco de sangue público baiano, com idade entre 19 e 66 anos. Coletaram-se amostras biológicas de 320 indivíduos e aplicou-se questionário epidemiológico em 309. Investigaram-se cinco polimorfismos de risco (GSTT1*nulo, GSTM1*nulo, CYP1A1*2C (rs1048943), XRCC1 399*Gln (rs25487) eXRCC1 194*Trp (rs1799782) e nove marcadores informativos de ancestralidade (AIMs), por meio de PCR para as inserções e/ou deleções, e PCR-RFLP ou Real Time-PCR para as mutações pontuais. Observou-se presença dos alelos de risco variando entre 12,3% e 56,5% dos indivíduos (XRCC1 194*Trp e XRCC1 399*Gln, respectivamente). A frequência do tabagismo foi 14,6%, etilismo 64,3% (12,7% azem uso abusivo de álcool). Os outros fatores de risco variaram entre 2,3% e 1,3% (relato de HPV e dificuldades de acesso aos serviços de saúde). A estimativa de ancestralidade mostrou maior contribuição ancestral nativo americana em portadores do genótipo GSTM1-nulo que nos não-nulo, o qual foi mais frequente em brancos. Não foi observada associação entre ancestralidade/raça e os fatores de risco ambientais. No entanto, alguns fatores de risco foram associados à baixa renda, e, principalmente, à baixa escolaridade. Contudo, embora a ancestralidade possa influenciar a suscetibilidade genética, não houve influência sobre a suscetibilidade ambiental já que os fatores de risco ambientais se relacionaram principalmente com aspectos socioeconômicos. / The oral squamous cell carcinomas (CEO) is the fourth most common cancer in northeastern Brazil and also in Bahia. Despite having a multifactorial etiology, at least 80% of cases are attributable to exposure to tobacco and alcohol. Individual susceptibility to CEO has been widely studied, and is attributed to genetic and socioeconomic factors. Genetic polymorphisms of risk, common in certain ancestral populations; lifestyle; information access and health services difficulty are examples of such factors. Given the high incidence of CEO in Bahia we investigated the distribution of risk factors for CEO in a sample from Bahia population. Participated in 332 voluntary blood donors of a public blood bank in Bahia, ages ranged from 20 to 66 years. Biological samples was collect from 320 individuals and epidemiological questionnaire was applied to 309. We investigated five polymorphisms of susceptibility (GSTT1*null, GSTM1*null, CYP1A1*2C (rs1048943), XRCC1 399*Gln (rs25487) and XRCC1 194*Trp (rs1799782)) and nine ancestry informative markers (AIMs) by PCR for insertions and/or deletions, and PCR-RFLP and Real Time-PCR for SNP. We observed the presence of risk alleles ranging from 12.3% to 56.5% of subjects (XRCC1 194*Trp and XRCC1-399*Gln, respectively). Smoking was prevalent in 14.6% of subjects, alcoholism in 64.3% (12.7% alcohol abuse). The other risk factors varied between 2.3% and 41.3% (reported HPV and poor access to health services). The ancestry estimative showed high contribution of Native American in individuals with genotype GSTM1*null, which was more common in whites. In this sample, there was no relationship between ancestry/race and environmental risk factors. However, some risk factors were associated with low income, and, especially, low schooling. However, while the ancestry can influence genetic susceptibility, no influence on the environmental susceptibility, which relates mainly to socioeconomic factors.

Orientador: Prof. Dr. Herculano da Silva Martinho / Dissertação (mestrado) - Universidade Federal do ABC, Programa de Pós-Graduação em Biotecnociência, 2017.

Background: Transcriptome analytic tools are commonly used across patient cohorts to develop drugs and predict clinical outcomes. However, as precision medicine pursues more accurate and individualized treatment decisions, these methods are not designed to address single-patient transcriptome analyses. We previously developed and validated the N-of-1-pathways framework using two methods, Wilcoxon and Mahalanobis Distance (MD), for personal transcriptome analysis derived from a pair of samples of a single patient. Although, both methods uncover concordantly dysregulated pathways, they are not designed to detect dysregulated pathways with up- and down-regulated genes (bidirectional dysregulation) that are ubiquitous in biological systems. Results: We developed N-of-1-pathways MixEnrich, a mixture model followed by a gene set enrichment test, to uncover bidirectional and concordantly dysregulated pathways one patient at a time. We assess its accuracy in a comprehensive simulation study and in a RNA-Seq data analysis of head and neck squamous cell carcinomas (HNSCCs). In presence of bidirectionally dysregulated genes in the pathway or in presence of high background noise, MixEnrich substantially outperforms previous single-subject transcriptome analysis methods, both in the simulation study and the HNSCCs data analysis (ROC Curves; higher true positive rates; lower false positive rates). Bidirectional and concordant dysregulated pathways uncovered by MixEnrich in each patient largely overlapped with the quasi-gold standard compared to other single-subject and cohort-based transcriptome analyses. Conclusion: The greater performance of MixEnrich presents an advantage over previous methods to meet the promise of providing accurate personal transcriptome analysis to support precision medicine at point of care.

Introduction: Chronic inflammation plays an important role on the transformation and tumor progression during oral carcinogenesis. There is a great number of chronic inflammatory lesions (CIL) in the oral cavity which are related to dysplastic processes of the epithelium, immune response and changes on the collagen deposition. Objectives: To investigate the presence of dysplasia and to histologically grade them in the CIL of traumatic cause, as well as toaccessthe density of mast cells and different types of collagen fibers in cases of epithelial dysplasias and oral squamous cell carcinomas (OSCC). Material and Method: Initially, 183 CIL cases were evaluated as to the presence of dysplasia and also classified according to its degree of epithelial dysplasia. Among those lesions, 45 CIL cases were selected and divided into two groups: group 1 (15 cases of mild dysplasia), group 2 (15 cases of moderate/severe dysplasia). The control group was composed by 15 cases of OSCC.They were stained with toluidine blue in order to quantify the mast cells and picrosirius red to semi-quantify the collagen type fibers. Results: The mast cells were detected in all groups presenting a mean of 6,76 cells/mm2, 10.82 cells/mm2 and 19.18 cells/mm2 in the control, group 1and 2 respectively. Regarding the collagen fibers, type III was more prevalent on groups 2 and control while type I fibers were more abundant on group 1. Conclusion: Oral chronic inflammatory lesions showed dysplastic changes in most analyzed cases. The results suggests an active participation of mast cells in the stage of tumor transformation, since it was detected a higher density onthe dysplasia cases when compared to the OSCC cases. Nevertheless, the gradual change of collagen type fibers indicates that collagenproducing cells become altered during the stages of dysplasia (tumor transformation). / Introdução: A inflamação crônica tem um papel importante na transformação e progressão tumoral durante a carcinogênese oral. Muitas lesões inflamatórias crônicas (LIC) da cavidade oral estão relacionadas a processos displásicos do epitélio, à resposta imune e à mudança na deposição do colágeno. Objetivos: Investigar a presença de displasia e graduá-las histologicamente nas LIC de origem traumática, como também, avaliar a densidade de mastócitos e de diferentes tipos de fibras colágenas nas LIC com displasias epiteliais e comprar aos casos de carcinomas de células escamosas (CCE). Material e Métodos: Inicialmente 183 LIC foram avaliadas quanto à presença de displasia e classificadas em relação ao grau. Em seguida, 45 casos foram divididos em: Grupo controle (CCE), Grupo 1 (displasia leve- DL), Grupo 2 (displasia moderada/severa- DM/S). Foram corados com Azul de Toluidina para quantificar os mastócitos e Picrosirius Red para avaliação dos tipos de fibras colágenas I e III. Resultados: As LIC foram mais frequentes em mulheres (n=107) com idade de 36,6 anos. O sítio mais afetado foi a mucosa do lábio inferior (29,7%), já a lesão mais frequente foi o fibroma traumático (39,2%). A displasia leve esteve presente em 56,3% da amostra. Os mastócitos foram evidenciados nos três grupos: grupo controle (6,76 mastócitos/mm), grupo 1 (10,82 mastócitos/mm2) e grupo 2 (19,18 mastócitos/mm2).Quando analisadas as fibras colágenas, observouse no grupo controle e no grupo 2 que as fibras tipo III foram mais prevalentes, já no grupo 1 prevaleceu-se as fibras tipo I. Conclusão: Lesões inflamatórias crônicas orais apresentaram alterações displásicas na maior parte dos casos. O estudo sugere uma participação dos mastócitos na fase de transformação tumoral. E a alteração gradativa dos colágenos tipo I e III indica alteração das células produtoras de colágeno, durante transformação tumoral.

Distant brain metastases from oral squamous cell carcinomas (OSCC) are extremely rare. Here we describe a case of a 53-year-old man with a primary OSCC who referred to the neurosurgical department because of epileptic seizures. MR imaging revealed an enhancing lesion in the right parietal lobe. A craniotomy with tumor removing was performed. Histopathological examination verified an invasive, minimally differentiated metastasis of the primary OSCC. The patient refused whole brain radiation therapy and died from pulmonary metastatic disease 10 months after the neurosurgical intervention without any cerebral recurrence. To the authors’ knowledge, only two similar cases have been previously reported.

Overall survival of the metastatic forms of epithelial derived cancers, especially head and neck squamous cell carcinomas (HNSCC), has not significantly improved even with the application of aggressive combined modality approaches incorporating radiation and chemotherapy. Cumulative evidence implicates the epidermal growth factor receptor (EGFR) as an important therapeutic target in HNSCC. We have previously demonstrated that the combination of lovastatin, a potent inhibitor of the mevalonate pathway, with EGFR tyrosine kinase inhibitors induced robust synergistic cytotoxicity. However, the use of high dose statins in our clinical trial was associated with significant toxicities including higher than anticipated rate of muscle pathologies. Our goal was to uncover novel downstream targets of the mevalonate pathway that may enhance the efficacy or limit toxicities of this novel combination therapeutic approach. In this study we have demonstrated that GGTI-298, an inhibitor of protein geranylgeranylation, through its ability to disrupt the actin cytoskeleton, inhibits EGFR dimerization and cellular trafficking. This novel mechanism targeting the EGFR has clinical implications as GGTI-298 in combination with tarceva, a clinically relevant EGFR inhibitor, showed enhanced cytotoxicity and inhibitory effects on EGFR activation and its downstream signaling.

Overall survival of the metastatic forms of epithelial derived cancers, especially head and neck squamous cell carcinomas (HNSCC), has not significantly improved even with the application of aggressive combined modality approaches incorporating radiation and chemotherapy. Cumulative evidence implicates the epidermal growth factor receptor (EGFR) as an important therapeutic target in HNSCC. We have previously demonstrated that the combination of lovastatin, a potent inhibitor of the mevalonate pathway, with EGFR tyrosine kinase inhibitors induced robust synergistic cytotoxicity. However, the use of high dose statins in our clinical trial was associated with significant toxicities including higher than anticipated rate of muscle pathologies. Our goal was to uncover novel downstream targets of the mevalonate pathway that may enhance the efficacy or limit toxicities of this novel combination therapeutic approach. In this study we have demonstrated that GGTI-298, an inhibitor of protein geranylgeranylation, through its ability to disrupt the actin cytoskeleton, inhibits EGFR dimerization and cellular trafficking. This novel mechanism targeting the EGFR has clinical implications as GGTI-298 in combination with tarceva, a clinically relevant EGFR inhibitor, showed enhanced cytotoxicity and inhibitory effects on EGFR activation and its downstream signaling.