Phase II trial of bortezomib alone or in combination with irinotecan in patients with adenocarcinoma of the gastroesophageal junction or stomach.

PURPOSE: To determine the effectiveness of bortezomib plus irinotecan and bortezomib alone in patients with advanced gastroesophageal junction (GEJ) and gastric adenocarcinoma. We also sought to explore the effect of these therapeutics on tumor and normal gene expression in vivo. METHODS: Forty-one patients with advanced GEJ (89 %) or gastric (11 %) adenocarcinoma received bortezomib (1.3 mg/m(2) days 1, 4, 8, 11) plus irinotecan (125 mg/m(2) days 1, 8) every 21 days as first line therapy (N = 29), or bortezomib alone as second line therapy (N = 12). The trial was designed to detect a 40 % response rate for the combination, and 20 % response rate for bortezomib alone. Affymetrix HU133A gene chip arrays were used for gene expression studies. RESULTS: Objective response occurred in 3 of 29 patients (10 %, 95 % confidence intervals [CI] 2 %, 27 %) treated with bortezomib plus irinotecan, and in 1 of 12 patients (8 %, 95 % CI 0 %, 39 %) with bortezomib alone. Due to the limited number of responders, there were no significant correlations with response found in the gene expression profiles of 12 patients whose tumors were sampled before and 24 h after therapy with bortezomib alone (N = 2) or the combination (N = 10). CONCLUSIONS: We conclude that bortezomib is not effective for the treatment of advanced adenocarcinoma of the GEJ or stomach, whether used alone or in combination with irinotecan, in an unselected patient population.

Phase II trial of the ribonucleotide reductase inhibitor 3-aminopyridine-2-carboxaldehydethiosemicarbazone plus gemcitabine in patients with advanced biliary tract cancer.

BACKGROUND: 3-Aminopyridine-2-carboxaldehydethiosemicarbazone (3-AP) is a novel small molecule ribonucleotide reductase (RR) inhibitor which is more potent than hydroxyurea, the prototype of RR inhibitors. 3-AP enhances the cellular uptake and DNA incorporation of gemcitabine in tumor cell lines. We evaluated the combination of 3-AP plus gemcitabine in advanced biliary tract adenocarcinoma. METHODS: Thirty-three patients with advanced adenocarcinoma of the gall bladder or biliary tract received gemcitabine (1,000 mg/m(2) on days 1, 8, and 15 every 28 days) 1 h after completing a 4-h infusion of 3-AP given at a dose of 105 mg/m(2) in patients with normal liver function (stratum A) or 80 mg/m(2) if abnormal liver function (stratum B). The trial was designed to determine whether the response rate was at least 30% in stratum A and 20% in stratum B. RESULTS: Objective response occurred in 3 of 23 patients (13%, 95% confidence intervals [CI] 3, 34%) with normal liver function, and in 0 of 10 patients with abnormal liver function. The most common grade 3-4 adverse events in all patients included neutropenia (42%), infection (33%), thrombocytopenia (27%), anemia (18%), and fatigue (15%). Fine needle aspiration of tumor samples obtained before and 24 h after 3-AP therapy showed increased R2 mRNA expression by in situ RT-PCR, suggesting RR inhibition. CONCLUSIONS: Despite evidence for RR inhibition in vivo, the 3-AP plus gemcitabine combination is not likely to be associated with a response rate exceeding 30% in patients with adenocarcinoma of the biliary tract.

Anti-prostate-specific membrane antigen-based radioimmunotherapy for prostate cancer.

Despite recent advances, advanced prostate cancer is suboptimally responsive to current chemotherapeutic agents. Radiolabeled monoclonal antibody therapy that targets prostate-specific membrane antigen (PSMA) shows promise and is an area of active investigation. J591 is a deimmunized IgG monoclonal antibody developed to target the extracellular domain of PSMA. Preclinical and early phase clinical studies using radiolabeled J591 have demonstrated efficacy in targeting tumor cells and decreasing levels of prostate-specific antigen. Radiolabeled J591 is well-tolerated, nonimmunogenic, and can be administered in multiple doses. The dose-limiting toxicity is reversible myelosuppression with little nonhematologic toxicity. Future studies will include approaches to optimize patient selection and incorporate novel strategies to improve the success of anti-PSMA radioimmunotherapy.