We conclude that HNSCC in young individuals should prompt clinicians to obtain a family history and consider that the patient may have a germline p16 defect that could predispose them to other cancers, including melanoma and pancreatic cancer.
We also present evidence indicating that, when performed serially in individuals harboring a p16 germ-line mutation bestowing a high risk for pancreatic cancer, MLDA may be an effective tool for the longitudinal assessment of risk and early detection of pancreatic cancer.
Here, we inducibly re-expressed p16 in vivo in an orthotopic model of pancreatic cancer and examined the impact on these clinically relevant aspects of pancreatic cancer tumour biology.
Evaluation of clinical relevance of examining K-ras, p16 and p53 mutations along with allelic losses at 9p and 18q in EUS-guided fine needle aspiration samples of patients with chronic pancreatitis and pancreatic cancer.
Using LD-PCR, mutations in p53 and/or p16 were found in the pancreatic juice of 12 of 20 individuals with pancreatic cancer compared to only 1 of 8 patients with chronic pancreatitis, 0 of 8 individuals without evidence of pancreatic disease (p<0.02).
GenoMEL, comprising major familial melanoma research groups from North America, Europe, Asia, and Australia has created the largest familial melanoma sample yet available to characterize mutations in the high-risk melanoma susceptibility genes CDKN2A/alternate reading frames (ARF), which encodes p16 and p14ARF, and CDK4 and to evaluate their relationship with pancreatic cancer (PC), neural system tumors (NST), and uveal melanoma (UM).
A group I intron ribozyme was designed to trans-splice the 2 base-deleted p16 transcripts with the wild-type sequence in a pancreatic cancer cell line, which originally produced no p16.
Additionally, we analysed the aberrant methylation frequency of cell cycle inhibitor p16(INK4a) and K-ras gene mutations in the pancreatic samples. p16 inactivation was detected in 43% of adenocarcinomas, in 17% of neuroendocrine tumors, in 18% of pancreatitis and in 63% of pancreas cancer cell lines.
The incidence of p16 mutations was 2 (9%) in 22 cases of pancreatic carcinoma with strongly positive staining, 4 (17%) in 24 with weakly positive staining, and 3 (21%) in 14 with negative staining.
The effect was specific to pRB depletion because two other human pancreatic cancer cell lines that retained high pRB expression after p16 transfection were resistant to chemotherapy-induced apoptosis.
Because aberrant methylation of ppENK or p16 was more often detected in similar grade PanINs from patients with pancreatic carcinoma than in those with other pancreatic diseases, it may be a useful indicator of the potential malignancy of epithelial cells of the pancreas.
CDKN2A is a tumor suppressor gene that encodes p16 (which inhibits activity of the cyclin D1-CDK4 complex) with germline mutations detected in 10%-25% of melanoma-prone families, some of whom are also prone to pancreatic cancer.
These data indicate that AdexCACSp16 has the potential to induce p16 gene expression and control pancreas cancer cell proliferation and that the adenovirus p16 expression vector AdexCACSp16 might be a possible method of gene therapy to improve the surgical therapeutic results for pancreas cancer.