PubMed Health⌕ Search

Biomedical subjects

James Abbruzzese

Publications and source records attributed to James Abbruzzese.

12 recordsLinked to original sources

Potentiation of the effect of erlotinib by genistein in pancreatic cancer: the role of Akt and nuclear factor-kappaB.

The epidermal growth factor receptor (EGFR) is a target of new therapies in most nonhematologic cancers. EGFR blockade alone may not be sufficient for the control of growth and invasion of human pancreas cancer because of the independent activation of Akt and nuclear factor-kappaB (NF-kappaB). The expression of EGFR, Akt, and NF-kappaB was determined in six human pancreatic cancer cell lines. Selected cells for specific expression were treated with erlotinib, genistein, gemcitabine, or the combination. Growth inhibition was evaluated using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, and apoptosis was assayed by ELISA. EGFR, phosphorylated EGFR, phosphorylated Akt, and survivin expressions were determined by immunoblotting. Electrophoretic mobility shift assay was used to evaluate the DNA binding activity of NF-kappaB. Genistein significantly increased (P < 0.05) erlotinib-induced growth inhibition and apoptosis in BxPC-3, CAPAN-2, and AsPC-1 cells. In the BxPC-3 cell line, significant down-regulation of EGFR, phosphorylated Akt, NF-kappaB activation, and survivin was observed in the cells treated with the combination compared with the erlotinib-treated cells. In the HPAC and MIAPaCa cell line, no potentiation of the effects of erlotinib by genistein on cell growth or inhibition of the EGFR/Akt/NF-kappaB was observed. Genistein potentiated growth inhibition and apoptosis of the gemcitabine and erlotinib combination in COLO-357 cell line. Genistein potentiates the growth inhibition and apoptosis induced by erlotinib and gemcitabine in certain pancreatic cancer cells. Akt and NF-kappaB inhibition represents one of the mechanisms for the potentiation of erlotinib- and gemcitabine-induced cell death by genistein.

Apoptosis↗

Molecular evidence for increased antitumor activity of gemcitabine by genistein in vitro and in vivo using an orthotopic model of pancreatic cancer.

Soy isoflavone genistein exhibits growth inhibitory activity against human pancreatic cancer cell lines. We previously reported the potential of genistein to augment chemotherapeutic response of pancreatic cancer cells in vitro. In the present study, we investigated whether genistein pretreatment could be used as a novel strategy for gemcitabine-induced killing in vitro and enhanced antitumor activity in vivo using an orthotopic tumor model. We conducted our studies using paired isogenic human pancreatic cancer cell line with differences in metastatic behavior (COLO 357 and L3.6pl). In vitro studies were done to measure growth inhibition and degree of apoptotic cell death induced by either genistein alone, gemcitabine alone, or genistein followed by gemcitabine. Our results show that pretreatment of cells with genistein for 24 hours followed by gemcitabine resulted in 60% to 80% growth inhibition compared with 25% to 30% when gemcitabine was used alone. The overall growth inhibition was directly correlated with apoptotic cell death irrespective of the metastatic potential of cells. Several genes that are known to inhibit apoptosis and contribute to chemoresistance such as nuclear factor-kappaB (NF-kappaB) and Akt were assessed to investigate the basis for the observed chemosensitizing effects of genistein. Genistein potentiated the gemcitabine-induced killing by down-regulation of NF-kappaB and Akt. In contrast, Akt and NF-kappaB were found to be up-regulated when pancreatic cancer cells were exposed to gemcitabine alone, suggesting the potential mechanism of acquired chemoresistance. In addition to in vitro results, we show here for the first time, that genistein in combination with gemcitabine is much more effective as an antitumor agent compared with either agent alone in our orthotopic tumor model. But most importantly, our data also showed that a specific target, such as NF-kappaB, was inactivated in genistein-treated animal tumors and that gemcitabine-induced activation of NF-kappaB was completely inhibited in animal tumors treated with genistein and gemcitabine. These results provide strong molecular in vivo evidence in support of our hypothesis that inactivation of NF-kappaB signaling pathway by genistein could also abrogate gemcitabine-induced activation of NF-kappaB resulting in the chemosensitization of pancreatic tumors to gemcitabine, which is likely to be an important and novel strategy for the treatment of pancreatic cancer.

Animals↗

Nuclear factor-kappaB and IkappaB kinase are constitutively active in human pancreatic cells, and their down-regulation by curcumin (diferuloylmethane) is associated with the suppression of proliferation and the induction of apoptosis.

BACKGROUND: Pancreatic carcinoma is a lethal malignancy, with the best available therapeutic option-gemcitabine-yielding response rates of < 10%. Because nuclear factor-kappaB (NF-kappaB) has been determined to play a role in cell survival/proliferation in human pancreatic carcinoma, this transcription factor is a potential therapeutic target. METHODS: The authors investigated the ability of curcumin (diferuloylmethane), an agent that is pharmacologically safe in humans, to modulate NF-kappaB activity. RESULTS: NF-kappaB and IkappaB kinase (IKK) were constitutively active in all human pancreatic carcinoma cell lines examined, and curcumin consistently suppressed NF-kappaB binding (as assessed using an electrophoretic mobility gel-shift assay) and IKK activity. Curcumin decreased the expression of NF-kappaB-regulated gene products, including cyclooxygenase-2 (as assessed using immunoblot analysis), prostaglandin E2, and interleukin-8 (as assessed using an enzyme-linked immunoassay), all of which have been implicated in the growth and invasiveness of pancreatic carcinoma. These changes were associated with concentration- and time-dependent antiproliferative activity (as assessed using a 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide [MTT] assay) and proapoptotic effects (as assessed via annexin V/propidium iodide staining [fluorescence-activated cell sorting, as well as with the induction of polyadenosine-5'-diphosphate-ribose polymerase cleavage). CONCLUSIONS: Curcumin down-regulated NF-kappaB and growth control molecules induced by NF-kappaB in human pancreatic cells. These effects were accompanied by marked growth inhibition and apoptosis. Through these findings, the authors provided a biologic rationale for the treatment of patients with pancreatic carcinoma using this nontoxic phytochemical.

Antineoplastic Agents↗

Diagnostic protein discovery using proteolytic peptide targeting and identification.

Plasma protein profiling with mass spectrometry is currently being evaluated as a diagnostic tool for cancer and other diseases. These experiments consist of three steps: plasma protein fractionation, analysis with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS), and comparisons of the MALDI profiles to develop diagnostic fingerprints using bioinformatic techniques. While preliminary results appear promising in small sample groups, the method is limited by the sensitivity of MALDI-MS for intact proteins, the limited mass range of MALDI-MS, and difficulties associated with isolating individual proteins for identification to validate the diagnostic fingerprint. Here we present an alternative and improved method directed toward diagnostic protein discovery, which incorporates proteolytic peptide profiling, bioinformatic targeting of ion signals, and MALDI tandem mass spectrometry (MS/MS) peptide sequencing, rather than fingerprinting. Pancreatic cancer patients, pancreatitis patients, and controls are used as the model system. Profiling peptides after enzymatic digestion improves sensitivity and extends the accessible protein molecular weight range when compared to intact protein profiling. The first step is to extract and fractionate the proteins from plasma. Each fraction is digested with trypsin and subsequently analyzed by MALDI-MS. Rather than using bioinformatic analysis as a pattern-matching technique, peptides are targeted based on the disease to control peak intensity ratios measured in the averages of all mass spectra in each group and t-tests of the intensity of each individual peak. The targeted peptide ion signals are subsequently identified using MALDI-MS/MS in quadrupole-TOF and tandem-TOF instruments. This study found not only the proteins targeted and identified by a previous protein profiling experiment, but also detected additional proteins. These initial results are consistent with the known biology of pancreatic cancer or pancreatitis, but are not specific to those diseases.

Adult↗

Chemotherapy and radiation of anal canal cancer: the first approach.

Since the late 1970's, increasing evidence from single-arm phase II studies has indicated that combined modality therapy yields a complete response rate of approximately 80-90% in most patients with squamous cell cancers of the anal canal. Surgery, most commonly an abdominoperineal resection, is reserved for salvage therapy. Although patients with large primary tumors (>5 cm) have a lower complete response rate of 50-75%, the majority of patients may be spared a colostomy and have an excellent overall survival. This chapter reviews the recent literature of patients treated for squamous cell, basaloid, and cloacogenic carcinoma (collectively defined as squamous cell cancer) of the anal canal.

Antineoplastic Agents↗

Randomized phase II comparison of dose-intense gemcitabine: thirty-minute infusion and fixed dose rate infusion in patients with pancreatic adenocarcinoma.

PURPOSE: To conduct a randomized phase II trial of dose-intense gemcitabine using a standard 30-minute infusion or the fixed dose rate (FDR) infusion (10 mg/m2/min) in patients with pancreatic adenocarcinoma. PATIENTS AND METHODS: In this prospective trial, patients with locally advanced and metastatic pancreatic adenocarcinoma were treated with 2,200 mg/m2 gemcitabine over 30 minutes (standard arm) or 1,500 mg/m2 gemcitabine over 150 minutes (FDR arm) on days 1, 8, and 15 of every 4-week cycle. The primary end point of this trial was time to treatment failure. Secondary end points included time to progression, median survival, safety, and pharmacokinetic studies of gemcitabine. RESULTS: Ninety-two patients were enrolled onto this study; 91% of the patients had metastatic disease. Time to treatment failure was comparable in both treatment groups; however, the median survival for all patients was 5.0 months in the standard arm and 8.0 months in the FDR arm (P =.013). For patients with metastases, the median survival was 4.9 months in the standard arm and 7.3 months in FDR arm (P =.094). The 1- and 2-year survival rates for all patients were 9% (standard arm) versus 28.8% (FDR; P =.014) and 2.2% (standard arm) versus 18.3% (FDR; P =.007), respectively. Patients in the FDR infusion arm experienced consistently more hematologic toxicity. Pharmacokinetic analyses demonstrated a two-fold increase in intracellular gemcitabine triphosphate concentration in the FDR arm (P =.046). CONCLUSION: Pharmacokinetic and clinical data in this trial supports the continued evaluation of the FDR infusion strategy with gemcitabine.

Adenocarcinoma↗

Phase II study of MGI-114 administered intravenously for 5 days every 28 days to patients with metastatic colorectal cancer.

We examined the use of MGI-114 (6-hydroxymethyacylfulvene) for the treatment of patients with advanced colorectal carcinoma. Twenty-six patients were enrolled, with a median age of 60 years (range 41-75); 64% were male and all patients had a performance status of 0 or 1. We administered a dose of 11 mg/m2/d x 5 days every 4 weeks. With a median of two cycles (range 0-6) administered, no complete responses or partial responses were observed. Four patients had no change in disease (16%); 15 patients (57%) had progressive disease; seven patients were inevaluable (27%). Toxicity was evaluated in 25 of 26 patients. The main toxicities were hematologic, including granulocytopenia and thrombocytopenia. Neuropsychiatric adverse events included hallucination (7.7%), depression/anxiety (15.4%), and/or insomnia (19.2%). Given the lack of antitumor activity, further study of MGI-114 in colorectal cancer does not appear warranted.

Adult↗

Hepatic arterial infusion of a replication-selective oncolytic adenovirus (dl1520): phase II viral, immunologic, and clinical endpoints.

Replication-selective oncolytic adenoviruses are being developed for the treatment of cancer, but the safety and feasibility of repeated adenovirus delivery to tumors via the bloodstream was unknown, particularly in light of a patient death after hepatic artery infusion of a replication-defective adenovirus vector. We performed a Phase II trial of an oncolytic replication-selective adenovirus (dl1520, also known as Onyx-015) administered by hepatic artery infusion in patients with gastrointestinal carcinoma metastatic to the liver (n = 27). dl1520 was infused into the hepatic artery (2 x 10(12) particles) on days 1 and 8 as a single agent, and thereafter starting on day 22 in combination with i.v. 5-fluorouracil and leucovorin every 28 days. Repeated viral infusions were feasible, and no deaths occurred on study; reversible grade 3/4 hyperbilirubinemia occurred in 2 patients. Systemic inflammatory cytokine responses varied greatly between patients and even between cycles within a given patient. Proinflammatory cytokines [e.g., tumor necrosis factor, IFN-gamma, and interleukin (IL) 6] typically rose within 3 h and were followed at 18 h by a rise in IL-10. However, in the single patient who suffered a severe but reversible systemic inflammatory response, a unique cytokine profile was detected: marked acute increases of IL-6 (20-fold higher than average for all of the patients) and inhibition of IL-10 production. Delayed secondary peaks of viremia were reproducibly detected 3-6 days after treatment, even in the presence of high level neutralizing antibody titers and antiviral cytokines. Mathematical modeling was used to calculate the number of virus particles produced and shed into the blood with each replication cycle. The combination of virotherapy and chemotherapy had antitumoral activity in some chemotherapy-resistant colorectal tumors. The intra-arterial infusion of oncolytic adenoviruses warrants additional study.

Adenoviruses, Human↗

Mouse Models of Metastatic Pancreatic Adenocarcinoma.

Pancreatic adenocarcinoma is a deadly disease. Its etiology is unknown, and metastatic disease kills themajority of patients who have it. Effective prevention is clearly the ultimate goal for eradicating this diseaseprovided that the effects of environmental and genetic elements on pancreatic cancer development arefully understood. Currently, it appears that the control of pancreatic cancer metastasis is of immediateurgency. Fulfillment of this difficult task relies on knowledge of the cellular and molecular biology of metastasis.The use of relevant animal models will help define each aspect of this complicated process.

Journal Article↗

A Novel, Clinically Relevant Animal Model of Metastatic Pancreatic Adenocarcinoma Biology and Therapy.

In this study, we report a metastatic model of Panc02 murine pancreatic adenocarcinoma. Parental Panc02cells were orthotopically implanted into the pancreas of syngeneic C57BL/6 mice. Tumor cells were isolatedfrom liver micrometastases 90 d after tumor implantation and established as a culture (Panc02-H1).The Panc02-H1 cells were then implanted into the pancreas of mice. Liver metastases were then collectedand established as Panc02-H2 cells. This process was repeated until the Panc02-H7 cell line was established.These cells were extremely aggressive after implantation as manifested by progressive growth in the pancreas,peritoneal dissemination, and distant metastasis to multiple organs, including the liver and lungs.Moreover, Panc02-H7 cells expressed the inducible nitric oxide synthase gene at a very low level in cultureand produced highly vascularized tumors having a large number of infiltrating macrophages. Collectively,this model system should be a valuable tool for investigating the molecular mechanisms governing pancreaticcancer growth and metastasis and exploring potential treatment modalities for this disease.

Journal Article↗

Direct tandem mass spectrometry reveals limitations in protein profiling experiments for plasma biomarker discovery.

The low molecular weight plasma proteome and its biological relevance are not well defined; therefore, experiments were conducted to directly sequence and identify peptides observed in plasma and serum protein profiles. Protein fractionation, matrix-assisted laser desorption ionization mass spectrometry (MALDI-MS) profiling, and liquid-chromatography coupled to MALDI tandem mass spectrometry (MS/MS) sequencing were used to analyze the low molecular weight proteome of heparinized plasma. Four fractionation techniques using functionally derivatized 96-well plates were used to extract peptides from plasma. Tandem TOF was successful for identifying peptides up to m/z 5500 with no prior knowledge of the sequence and was also used to verify the sequence assignments for larger ion signals. The peptides (n>250) sequenced in these profiles came from a surprisingly small number of proteins (n approximately 20), which were all common to plasma, including fibrinogen, complement components, antiproteases, and carrier proteins. The cleavage patterns were consistent with those of known plasma proteases, including initial cleavages by thrombin, plasmin and complement proteins, followed by aminopeptidase and carboxypeptidase activity. On the basis of these data, we discuss limitations in biomarker discovery in the low molecular weight plasma or serum proteome using crude fractionation coupled to MALDI-MS profiling.

Biomarkers↗