Gene Therapy with p14/tBID Induces Selective and Synergistic Apoptosis in Mutant Ras and Mutant p53 Cancer Cells In Vitro and In Vivo.

Any gene therapy for cancer will be predicated upon its selectivity against cancer cells and non-toxicity to normal cells. Therefore, safeguards are needed to prevent its activation in normal cells. We designed a minimal p14 promoter with upstream Ap1 and E2F enhancer elements and a downstream MDR1 inhibitory element, TATA box, and a transcription initiation site (hereafter p14min).

C-Terminal p53 Palindromic Tetrapeptide Restores Full Apoptotic Function to Mutant p53 Cancer Cells In Vitro and In Vivo.

We previously demonstrated that a synthetic monomer peptide derived from the C-terminus of p53 (aa 361−382) induced preferential apoptosis in mutant p53 malignant cells, but not normal cells. The major problem with the peptide was its short half-life (half-life < 10 min.) due to a random coil topology found in 3D proton NMR spectroscopy studies.

Redirecting apoptosis to aponecrosis induces selective cytotoxicity to pancreatic cancer cells through increased ROS, decline in ATP levels, and VDAC.

Pancreatic cancer cell lines with mutated ras underwent an alternative form of cell death (aponecrosis) when treated concomitantly with clinically achievable concentrations of arsenic trioxide, ascorbic acid, and disulfiram (Antabuse; AAA). AAA's major effects are mediated through generation of intracellular reactive oxygen species (ROS) and more than 50% decline in intracellular ATP. N-acetyl cysteine and a superoxide dismutase mimetic prevented aponecrosis and restored intracellular ATP levels.

Capecitabine and temozolomide (CAPTEM) for metastatic, well-differentiated neuroendocrine cancers: The Pancreas Center at Columbia University experience.

Purpose: We evaluated the efficacy and safety of capecitabine and temozolomide (CAPTEM) in patients with metastatic neuroendocrine tumors (NETs) to the liver. This regimen was based on our studies with carcinoid cell lines that showed synergistic cytotoxicity with sequence-specific dosing of 5-fluorouracil preceding temozolomide (TMZ).

Methods: A retrospective review was conducted of 18 patients with NETs metastatic to the liver who had failed 60 mg/month of Sandostatin LAR™ (100%), chemotherapy (61%), and hepatic chemoembolization (50%).

The use of fluorescent probes in the study of reactive oxygen species in pancreatic cancer cells.

The use of fluorescent probes can be an easy and quick method to analyze whether or not reactive oxygen species (ROS) are involved in a particular cellular process or the result of a particular drug treatment. ROS activate a variety of cell signaling and death pathways including apoptosis and necrosis (Raha and Robinson. Am J Med Gen 106:62-70, 2001).

Activation of targeted necrosis by a p53 peptide: a novel death pathway that circumvents apoptotic resistance.

Cancer cells escape apoptosis by intrinsic or acquired mechanisms of drug resistance. An alternative strategy to circumvent resistance to apoptosis could be through redirection into other death pathways, such as necrosis. However, necrosis is a nonspecific, nontargeted process resulting in cell lysis and inflammation of both cancer and normal cells and is therefore not a viable alternative.

Selective induction of apoptosis through the FADD/caspase-8 pathway by a p53 c-terminal peptide in human pre-malignant and malignant cells.

A p53 C-terminal peptide (aa 361-382, p53p), fused at its C-terminus to the minimal carrier peptide of antennapedia (17 aa, Ant; p53p-Ant), induced rapid apoptosis in human cancer cells, via activation of the Fas pathway. We examined p53p-Ant mechanism of action, toxicity in various human normal, non-malignant, pre-malignant and malignant cancer cells and investigated its biophysical characteristics. p53p-Ant selectively induced cell death in only pre-malignant or malignant cells in a p53-dependent manner and was not toxic to normal and non-malignant cells.