Establishment and characterization of 4 new human pancreatic cancer cell lines: evidences of different tumor phenotypes.

OBJECTIVES: Pancreatic cancer still remains a challenge for its biological complexity and lack of effective therapeutic strategies. Establishing new pancreatic cancer cell lines is therefore of paramount importance to clarify its biology. METHODS: We established and characterized 4 new pancreatic cancer cell lines (PP78, PP109, PP117, and PP161) according to their genetic (K-Ras, TP53, CDKN2A, and MADH4; DNA fingerprinting; karyotype), cytostructural (cytokeratins 7, 8, 18, and 19 vimentin, and ezrin), and functional profiles (doubling time; migration assay). RESULTS: K-Ras, TP53, and CDKN2A gene alterations were detected in all 4 of them. Each cell line had a unique DNA profile revealed by DNA fingerprinting. A complex karyotype with numerous structural and numeric chromosomal abnormalities was present in each cell line. All 4 cell lines showed positivity for cytokeratins 7, 8, and 18. All but PP78 expressed cytokeratin 19, whereas vimentin was expressed only in PP117 and PP78 cells. A different ezrin cellular distribution was noticed in PP78 and PP117, being mostly located at membrane ruffles. This peculiar distribution was associated with the strongest migratory capability. CONCLUSIONS: Our results seem to confirm the pancreatic ductal adenocarcinoma heterogeneity; in fact, the same genetic abnormalities (K-Ras, TP53, and CDKN2A) may have different effects on tumor biology depending on cellular differentiation.

Development of combined DNA-based piezoelectric biosensors for the simultaneous detection and genotyping of high risk Human Papilloma Virus strains.

BACKGROUND: Human Papilloma Virus (HPV) is a DNA virus belonging to the Papovavirus family. Genital HPV types have been subdivided into medium-low risk, and high-risk (HPV 16 and 18), frequently associated with cervical cancer. Three DNA-based piezoelectric biosensors were here developed for a quick detection and genotyping of HPV. METHODS: We developed a method for the detection and genotyping of HPV in human cervical scraping samples based on coupling DNA piezoelectric sensors with Polymerase Chain Reaction (PCR). The novelty of this work was the design and immobilisation of a degenerate probe (chosen in a conserved region of the viral genome) for the simultaneous detection of 16 virus strains and of two specific probes (chosen in a less-conserved region of the viral genome) for genotyping. RESULTS: The three biosensors were optimised with synthetic oligonucleotides with good reproducibility (HPVdeg CV% (av) 9%, HPV16 CV%(av) 9%; HPV18 CV%(av) 11%) with a detection limit of 50 nM. Cervical scraping samples after PCR amplification (in 40-200 nM range), were tested without the need of label with high selectivity and reproducibility. The results were in agreement with a reference method used in routinary analysis. CONCLUSION: Piezoelectric biosensors have proven to be suitable for detection and genotyping of HPV.

P53 gene status in patients with advanced serous epithelial ovarian cancer in relation to response to paclitaxel- plus platinum-based chemotherapy and long-term clinical outcome.

BACKGROUND: The aim of this retrospective study was to assess whether p53 gene status has any predictive or prognostic relevance in patients with advanced, poorly-differentiated serous epithelial ovarian cancer treated with paclitaxel- plus platinum-based chemotherapy. MATERIALS AND METHODS: The study was conducted on 46 patients who underwent surgery followed by paclitaxel- plus carboplatin-based chemotherapy. The tumor tissue samples were analyzed for p53 gene mutations. The median follow-up of survivors was 50.3 months. RESULTS: Twenty-three patients (50%) showed p53 mutations at exons 5 to 9. Sixteen (34.8%) patients had a polymorphism at codon 72 in exon 4 (SNP codon 72): 10 were Pro/Pro homozygous and 6 Pro/Arg heterozygous. Four polymorphic patients had a second mutation at exons 5 to 9. An inverse correlation was evidenced between the SNP codon 72 and mutations at exons 5 to 9, with the latter more frequently found in wild-type (Arg/Arg) codon 72 (19/30 versus 4/16, 63.3% versus 25.0%; p=0.03) cases. A clear trend for a higher response rate and longer progression-free and overall survival was observed in wild-type p53 and Pro/Pro polymorphic patients as compared to patients with mutant p53. CONCLUSION: The addition of paclitaxel to carboplatin does not appear to overcome the negative predictive and prognostic significance of p53 gene mutations in serous ovarian cancer. Nevertheless, the comprehensive analysis of p53 genotype, including the SNP codon 72, warrants further investigation in order to envisage individual responsiveness to cancer therapy.