• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 4
  • 1
  • Tagged with
  • 5
  • 5
  • 5
  • 5
  • 3
  • 3
  • 3
  • 3
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Cytochrome P450 isoforms 1A1, 1B1 AND 2W1 as targets for therapeutic intervention in head and neck cancer

Presa, Daniela, Khurram, S.A., Zubir, A.Z.A., Swaroop, Sneha, Cooper, Patricia A., Morais, Goreti R., Sadiq, Maria, Sutherland, Mark, Loadman, Paul, McCaul, Jim, Shnyder, Steven, Patterson, Laurence H., Pors, Klaus 11 December 2023 (has links)
Yes / Epidemiological studies have shown that head and neck cancer (HNC) is a complex multistage process that in part involves exposure to a combination of carcinogens and the capacity of certain drug-metabolising enzymes including cytochrome P450 (CYP) to detoxify or activate such carcinogens. In this study, CYP1A1, CYP1B1 and CYP2W1 expression in HNC was correlated with potential as target for duocarmycin prodrug activation and selective therapy. In the HNC cell lines, elevated expression was shown at the gene level for CYP1A1 and CYP1B1 whereas CYP2W1 was hardly detected. However, CYP2W1 was expressed in FaDu and Detroit-562 xenografts and in a cohort of human HNC samples. Functional activity was measured in Fadu and Detroit-562 cells using P450-Glo™ assay. Antiproliferative results of duocarmycin prodrugs ICT2700 and ICT2706 revealed FaDu and Detroit-562 as the most sensitive HNC cell lines. Administration of ICT2700 in vivo using a single dose of ICT2700 (150 mg/kg) showed preferential inhibition of small tumour growth (mean size of 60 mm3) in mice bearing FaDu xenografts. Significantly, our findings suggest a potential targeted therapeutic approach to manage HNCs by exploiting intratumoural CYP expression for metabolic activation of duocarmycin-based prodrugs such as ICT2700. / The authors would like to thank Bradford Institute for Health Research for funding a PhD studentship to DP through a competitive scheme and Yorkshire Cancer Research programme Grant (B381PA) for supporting our cytochrome P450-focused drug discovery research.
2

Course of Self-Reported Dysphagia, Voice Impairment and Pain in Head and Neck Cancer Survivors

Zebralla, Veit, Wiegand, Susanne, Dietz, Andreas, Wichmann, Gunnar, Neumuth, Thomas, Mehnert-Theuerkauf, Anja, Hinz, Andreas 27 April 2023 (has links)
Background: Head and neck cancer (HNC)-specific symptoms have a substantial impact on health-related quality of life. The aim of this study was to determine whether self-reported dysphagia, voice problems and pain of HNC patients changed over time and whether specific clinical or sociodemographic variables were associated with these symptoms. Methods: HNC patients (n = 299) in an outpatient setting answered questionnaires (Eating Assessment Tool-10; questions from the EORTC QLQ-C30 and EORTC H&N35) on dysphagia, voice problems and pain, collected with the software “OncoFunction” at three different timepoints (t1–t3) after diagnosis. The mean score changes from t1 to t3 were expressed in terms of effect sizes d. The impact of sociodemographic and clinical factors on the course of the variables was tested with multivariate analyses of variance. Results: Dysphagia, voice impairment and pain in HNC survivors significantly improved over a period of approximately 14 months after diagnosis. Tumor site, stage, treatment modality, occupational state and ECOG state were significantly correlated with self-reported functional outcome. The pain level of the HNC patients was rather low. Conclusions: Patients suffer from functional impairments after HNC treatment, but an improvement in self-reported symptoms could be demonstrated within this time period.
3

Investigation of cytochrome p450 isoforms 1A1, 1B1 and 2W1 as targets for therapeutic intervention in head and neck cancer. Probing CYP1A1, 1B1 and 2W1 activity with duocarmycin bioprecursors

Presa, Daniela January 2018 (has links)
The full text will be available at the end of the embargo: 17th July 2024
4

Vismodegib – Inhibitor des Hedgehog-Signaltransduktionsweges – in der ex-vivo-Chemoresponsetestung bei Kopf-Hals-Tumoren

Liebig, Hannes 28 September 2023 (has links)
Purpose: The Hedgehog-signalling pathway (Hh) is frequently active in head and neck squamous cell carcinoma (HNSCC). Overexpressed Hh associates with poor prognosis. The Hh inhibitor vismodegib targets smoothened (SMO) and, based on molecular data, may prevent resistance to EGFR targeting. Methods: To elucidate potential roles of vismodegib in HNSCC therapy, its sole effects and those combined with cisplatin, docetaxel, and cetuximab on HNSCC cell lines were assessed by MTT metabolisation and BrdU incorporation. Colony formation (CF) of primary HNSCC cells was studied utilizing the FLAVINO-protocol. Combinatory effects were analysed regarding antagonism, additivity or synergism. Associations between the ex vivo detected mode of action of vismodegib with other treatments related to patient characteristics were assessed and progression-free survival (PFS) in patient groups compared using Kaplan-Meier curves. Results: Vismodegib suppressed BrdU incorporation significantly stronger than MTT turnover; CF was significantly inhibited at ≥20 µM vismodegib while concentrations <20 µM acted hormetic. Combining 20 µM vismodegib plus docetaxel (T), cisplatin (P), and cetuximab (E), additively enhanced antitumoral activity in HNSCC samples from patients with superior PFS highlighting a potential role for ex-vivo testing of this combination for use as a prognostic classifier. Conclusion: We provide ex-vivo evidence for vismodegib’s potential in HNSCC therapies especially if combined with cetuximab, cisplatin and docetaxel.:Abkürzungsverzeichnis 1 Einleitung 1.1 Kopf-Hals-Tumore 1.1.1 Therapie von Kopf-Hals-TumoreN 1.1.2 Limitationen der etablierten Therapien 1.2 Eingesetzte Chemotherapeutika 1.2.1 Cisplatin 1.2.2 Docetaxel 1.2.3 Cetuximab 1.3 Hedgehog-Signaltransduktionsweg 1.3.1 Hedgehog-Signalweg und Karzinogenese 1.3.2 Vermittlung von Tumortherapieresistenz durch den Hedgehog-Signalweg 1.3.3 Zielgerichtete Tumortherapie durch Blockade des Hedgehog-Signalweges 1.4 Vismodegib 1.5 Ex-Vivo-Chemoresponse-Testung mittels FLAVINO-Assay 1.6 Zusammenfassung der Rationale der Untersuchung 1.7 Aufgabenstellung der Promotionsarbeit 2 Publikation 2.1 Reduzierte Proliferation und Koloniebildung von Plattenepithelkarzinomen der Kopf Hals Region unter dualer Inhibition des EGFR- und Hedgehog-Signalweges 3 Zusammenfassung der Arbeit 4 Literaturverzeichnis 5 Anlagen 5.1 Darstellung des Eigenanteils 5.2 Erklärung über die eigenständige Abfassung der Arbeit 5.3 Lebenslauf 5.4 Publikationen 5.5 Danksagung
5

Standardized Diagnostics Including PET-CT Imaging, Bilateral Tonsillectomy and Neck Dissection Followed by Risk-Adapted Post-Operative Treatment Favoring Radio-Chemotherapy Improve Survival of Neck Squamous Cell Carcinoma of Unknown Primary Patients

Wichmann, Gunnar, Willner, Maria, Kuhnt, Thomas, Kluge, Regine, Gradistanac, Tanja, Wald, Theresa, Fest, Sandra, Lordick, Florian, Dietz, Andreas, Wiegand, Susanne, Zebralla, Veit 28 March 2023 (has links)
Background: About five to 10% of cancers in the head and neck region are neck squamous cell carcinoma of unknown primary (NSCCUP). Their diagnosis and treatment are challenging given the risk of missing occult tumors and potential relapse. Recently, we described human papillomavirus (HPV)-related NSCCUP-patients (NSCCUP-P) as a subgroup with superior survival. However, standardized diagnostic workup, novel diagnostic procedures, decision-making in the multidisciplinary tumor board (MDTB) and multimodal therapy including surgery and post-operative radio-chemotherapy (PORCT) may also improve survival. Methods: For assessing the impact of standardized diagnostic processes simultaneously established with the MDTB on outcome, we split our sample of 115 NSCCUP-P into two cohorts treated with curative intent from 1988 to 2006 (cohort 1; n = 53) and 2007 to 2018 (cohort 2; n = 62). We compared diagnostic processes and utilized treatment modalities applying Chi-square tests, and outcome by Kaplan–Meier plots and Cox regression. Results: In cohort 2, the standardized processes (regular use of [18F]-FDG-PET-CT imaging followed by examination under anesthesia, EUA, bilateral tonsillectomy and neck dissection, ND, at least of the affected site) improved detection of primaries (P = 0.026) mostly located in the oropharynx (P = 0.001). From 66.0 to 87.1% increased ND frequency (P = 0.007) increased the detection of extracapsular extension of neck nodes (ECE+) forcing risk factor-adapted treatment by increased utilization of cisplatin-based PORCT that improved 5-years progression-free and overall survival from 60.4 and 45.3 to 67.7% (P = 0.411) and 66.1% (P = 0.025). Conclusions: Standardized diagnostic workup followed by ND and risk-factor adapted therapy improves survival of NSCCUP-P.

Page generated in 0.0997 seconds