Thesis (Ph. D.)--University of Hong Kong, 2006. / Title proper from title frame. Also available in printed format.

Head and neck cancer (HNC) makes up 6 ¢H of the cancer patients in the world every year. This disease usually occurs in males and the incidence is increasing year by year. According to statistical analysis, HNC has less than 50 ¢H five-year survival rate. Therefore, the research of HNC seems imminent so that may lead to the development of new approaches of diagnosis and therapy. Recent research had shown that expression of podoplanin caused cellular proliferation, and may be associated with tumor invasion, metastasis and malignant prognosis. Podoplanin, a mucin-type transmembrane sialoglycoprotein, is highly expressed in lymphatic endothelial cells but not expressed in vascular endothelial cells. The purpose of this study was to determine the clinical and pathological significance of podoplanin in oral squamous cell carcinoma (OSCC). Therefore, we collected clinical specimen and associated patient history of OSCC. Further, we used the human cell lines of HNSCC (Fadu, Hep2) to investigate the molecular regulation of podoplanin. Podoplanin expression was analyzed by RT-PCR and Western blot assay firstly. As shown, podoplanin was found to be overexpressed in tumors compared with normal adjacent tissues. Further, immunohistochemical analysis revealed the location of podoplanin expression in OSCC tissues. The results showed that podoplanin had higher expression in T4 stage tumor section than in normal adjacent tissues of OSCC samples, or in T1 stage. Here, podoplanin was highly expressed in the OSCC tumor cell and lymphatics of stage T4 OSCC tissue. Furthermore, we found that overexpression of podoplanin in OSCC patients was associated with decreased five-years survival rate. In the univariate analysis, several factors were statistically significantly associated with disease-specific survival rate, including Tumor stage, Nodal stage, and podoplanin expression. In the subsequent multivariate analysis, only Tumor stage and Nodal stage showed a trend toward worse disease-specific survival. To further investigate the regulatory mechanism of podoplanin and its position of expression within the cell, immunofluorescence and transfection were utilized to assay. The results showed that podoplanin was expressed in the nuclear membrane of the Fadu and Hep2 cell lines, and the PI3K/AKT signaling pathway was involved. We suggest that the role of podoplanin in OSCC should be further investigated for potential future treatment.

Cisplatin is an effective chemotheraputic agent for head and neck squamous cell carcinoma particularly in conjunction with radiation therapy. Unfortunately, its cytotoxic profile and associated systemic side effects limit its clinical efficacy. A localized delivery system was developed for cisplatin by processing calcium polyphosphate (CPP) in a multistep gelling protocol, with the goal of limiting its systemic toxicity and enhancing its overall clinical applicability. In addition, a novel method for processing the material was examined utilizing cold isostatic pressure (CIP) to allow for miniaturization of the system into an implantable device. The integration of cisplatin into the matrix was examined for efficient and dose dependent loading via dissolution of the final product and measurement of platinum concentrations by inductively coupled plasma optical emission spectrometry (ICP-OES). Drug release was measured in vitro by placing the CPP-cisplatin matrix into TRIS buffer solution while measuring the platinum concentration at given intervals from 0.5 hours to 14 days. The cytotoxicity of the cisplatin against L1210 cells was examined using an MTT assay following a 12-hour elution. The material demonstrated a predictable and dose dependent loading of cisplatin, although the release of the drug showed variability exemplified by a more pronounced burst release with aging of the stock CPP glass particulate. The CPP/cisplatin matrix exhibited cytotoxic effects after processing. This work suggests that further evaluation of this material as a matrix for cisplatin delivery should be undertaken in an attempt to normalize release, maximize the concentration within the system and further optimize the bead format in order to improve the potential for clinical usage.

Diss. (sammanfattning) Uppsala : Uppsala universitet, 2005. / Härtill 4 uppsatser.

Thesis (Ph. D.)--University of Hong Kong, 2008. / Includes bibliographical references (leaf 132-174) Also available in print.

Thesis (M. Phil.)--University of Hong Kong, 2008. / Also available online.

Thesis (M. Phil.)--University of Hong Kong, 2008.

Thesis (Ph. D.)--University of Hong Kong, 2008. / Includes bibliographical references (leaf 132-174) Also available online.

Thesis (doctoral)--Umeå University, Sweden, 1995. / Added t.p. with thesis statement inserted. Includes bibliographical references.

Thesis (Ph. D.)--Ohio State University, 2005. / Document formatted into pages; contains xviii, 169 p. Includes bibliographical references. Abstract available online via OhioLINK's ETD Center; full text release delayed at author's request until 2006 March 9.