PTEN and NDUFB8 aberrations in cervical cancer tissue.

Cervical cancer is one of the world's major health issues. Despite many studies in this field, the carcinogenetic events of malignant conversion in cervical tumours have not been significantly characterised. The first aim of this project was to investigate the mutation status of the tumour suppressor gene- Phosphatase and Tension Homolog (PTEN)--in cervical cancer tissue. The second aim of this study was the analysis in the same cervical cancer tissue for aberrations in the mitochondrial electron transport chain subunit gene NDUFB8, which is localised to the same chromosomal contig as PTEN. The third aim was the evaluation of the potential therapeutic anti-cancer drug 2,4-Thiazolidinediones (TZDs) and its affect in regulating the PTEN protein in a cervical cancer cell line (HeLa). To approach the aims, paraffin-embedded cancerous cervical tissue and non-cancerous cervical tissue were obtained. DNA recovered from those tissues was then used to investigate the putative genomic changes regarding the NDUFB8 gene utilising SYBR Green I Real-Time PCR. The PTEN gene was studied via Dual-Labelled probe Real-Time PCR. To investigate the protein expression change of the PTEN protein, HeLa cells were firstly treated with different concentrations of 2,4-Thiazolidinediones and the level of PTEN protein expression was then observed utilising standard protein assays. Results indicated that there were putative copy-number changes between the cancerous cervical tissue and non-cancerous cervical tissue, with regard to the PTEN locus. This implies a potential gain of the PTEN gene in cancerous cervical tissue. With regards to normal cervical tissue versus cancerous cervical tissue no significant melting temperature differences were observed with the SYBR Green I Real-Time PCR in respect to the NDUFB8 gene. A putative up-regulation of PTEN protein was observed in TZD treated HeLa cells.

Analysis of SDHD and MMP12 in an affected solar keratosis and control cohort.

The incidence of Squamous Cell Carcinoma (SCG) is growing in certain populations to the extent that it is now the most common skin lesion in young men and women in high ultraviolet exposure regions such as Queensland. In terms of incidence up to 40% of the Australian population over 40 years of age is thought to possess the precancerous Solar Keratosis (SK) lesion and with a small, but significant, chance of progression into SCC, understanding the genetic events that play a role in this process is essential. The major aims of this study were to analyse whole blood derived samples for DNA aberrations in genes associated with tumour development and cellular maintenance, with the ultimate aim of identifying genes associated with non-melanoma skin cancer development. More specifically the first aim of this project was to analyse the SDHD and MMP12 genes via Dual-Labelled Probe Real-Time PCR for copy number aberrations in an affected Solar Keratosis and control cohort. It was found that 12 samples had identifiable copy-number aberrations in either the SDHD or MMP12 gene (this means that a genetic section of either of these two genes is aberrantly amplified or deleted), with five of the samples exhibiting aberrations in both genes. The significance of this study is the contribution to the knowledge of the genetic pathways that are malformed in the progression and development of the pre-cancerous skin lesion Solar Keratosis.

Germline polymorphisms are potential metastasis risk and prognosis markers in breast cancer.

A number of theories have been proposed to account for the origins of metastasis, although none as yet have adequately explained all of its characteristics. With approximately 90% of cancer-related deaths due to the effects of disseminated tumors, improved understanding of this process is critical for reducing cancer-associated morbidity and mortality. Extensive research to investigate the molecular basis of this process has been conducted, and our lab has focused on the role of germline polymorphism in this complex process. Simple breeding experiments using a highly metastatic mouse model showed that germline polymorphisms significantly contribute to metastasis susceptibility. Genetic mapping studies revealed that a number of genomic regions are linked to metastasis susceptibility, including a metastasis modifier on mouse chromosome 19. Subsequent analysis identified Sipa1 as the most likely candidate for the observed linkage on Chr 19. Evaluation of SNPs in SIPA1 in a pilot association study in a human breast cancer cohort supported this possibility and demonstrated that SIPA1 polymorphisms are associated with various markers of poor prognosis including differential sentinel lymph node status. Taken together, these data suggest that germline polymorphism is an important modulating component in metastatic progression that needs to be investigated if we are to fully understand the metastatic process.