Warren Chow

High-dose chemotherapy and stem-cell rescue in the treatment of high-risk breast cancer: prognostic indicators of progression-free and overall survival.

PURPOSE To examine the predictive value of tumor- and treatment-specific prognostic indicators of relapse-free survival (RFS) and overall survival (OS) in patients with high-risk breast cancer (HRBC) treated with high-dose chemotherapy (HDCT) and stem-cell rescue. PATIENTS AND METHODS Between June 1989 and September 1994, 114 patients with HRBC (stage II with > or = 10 axillary lymph nodes involved, stage IIIA, and stage IIIB inflammatory carcinoma) received adjuvant chemotherapy followed by HDCT with etoposide, cyclophosphamide, and either doxorubicin (CAVP) or cisplatin (CCVP). Variables analyzed included stage, tumor size, number of axillary nodes involved, grade and receptor status, and types of adjuvant chemotherapy and radiation therapy and HDCT. RESULTS With a median follow-up time of 46 months (range, 23 to 93), Kaplan-Meier estimates of 3.5-year OS for stage II, IIIA, and IIIB HRBC are 82% (95% confidence interval [CI], 67% to 97%), 79% (95% CI, 67% to 91%), and 72% (95% CI, 53% to 91%); RFS estimates are 71% (95% CI, 56% to 85%), 57% (95% CI, 43% to 72%), and 50% (95% CI, 29% to 71%) irrespective of the HDCT regimen. In univariate analysis, the risk of relapse was lower for patients with progesterone receptor (PR)-positive tumors (risk ratio [RR], 0.43; 95% CI, 0.22 to 0.81; P = .01) and higher for patients with inflammatory carcinoma (RR, 2.20; 95% CI, 1.02 to 4.76; P = .05). OS was better for patients with PR (RR, 0.16; 95% CI, 0.05 to 0.55; P = .003) and estrogen receptor (ER)-positive tumors (RR, 0.42; 95% CI, 0.17 to 1.02; P = .05); OS was worse for patients with high-grade primary tumors (RR, 4.08; 95% CI, 1.21-13.7; P = .02). In multivariate analysis, PR positivity was associated with improved RFS (P = .01) and OS (P = .001). CONCLUSION HDCT in selected patients with HRBC is safe and warrants further evaluation. Patients with receptor-negative, high-grade, or inflammatory tumors require improvement in their therapeutic options. Better assessment of the role of HDCT awaits completion of ongoing randomized trials.

Prognostic Indicators and Survival in Patients With Stage IIIB Inflammatory Breast Carcinoma After Dose-Intense Chemotherapy

PURPOSE To improve treatment outcome for patients presenting with inflammatory breast cancer (IBC), we have sequentially developed and tested single and tandem dose-intense chemotherapy regimens (DICT). Tumor- and treatment-related factors were analyzed to generate a prognostic model. PATIENTS AND METHODS Between May 1989 and April 2002, 120 patients received conventional-dose chemotherapy, surgery, and sequentially developed single- or tandem-cycle DICT. Disease- and treatment-specific features were subjected to univariate and multivariate analysis to correlate with outcome. RESULTS At a median follow-up of 61 months (range, 21 to 161 months), estimated 5-year relapse-free survival (RFS) and overall survival (OS) were 44% (95% CI, 34% to 53%) and 64% (95% CI, 55% to 73%), respectively. In an age-adjusted multivariate analysis, RFS was better in patients with estrogen receptor (ER)/progesterone receptor (PR)-positive tumors (P =.002), for patients with fewer than four involved axillary nodes before DICT (P =.01), and in patients treated with radiation therapy (P =.001) and tandem DICT (P =.049). OS was improved in patients with ER/PR-positive tumors (P =.002), in those with fewer than four involved axillary nodes before DICT (P =.03), and in patients treated with radiation therapy (P =.002). CONCLUSION This retrospective analysis suggests that either single or tandem DICT can be administered safely and may benefit selected patients with stage IIIB IBC. Those with receptor-negative IBC and with four or more involved axillary nodes before DICT need improved neoadjuvant and postadjuvant intensification therapy. A prospective randomized trial of single versus tandem DICT would be required to confirm the potential benefit of tandem DICT in the setting of IBC.

Mitomycin C and menadione for the treatment of lung cancer: a phase II trial

SummaryA phase II trial of menadione [2.5 gm/m2 as a continuous intravenous (iv) infusion over 48 hours] followed by mitomycin C (10–20 mg/m2 iv bolus) administered every 4 to 6 weeks was performed in 23 patients with advanced lung cancer. Menadione, a vitamin K analog which lowers intracellular pools of reduced glutathione (GSH), was combined with mitomycin C in an attempt to overcome thiol-mediated resistance to alkylating agent chemotherapy. The median age of patients entered on this trial was 62 years; performance status ranged from 60–90%. Two of the 23 patients (9%; 95% confidence interval, 1% to 28%) had objective responses lasting 3.5 months and 13 months respectively, while 4 additional patients developed short unconfirmed responses (lacking follow-up response data to estimate response duration). Median survival for all patients was 5.5 months. Treatment with mitomycin C and menadione was well tolerated except for hematologic toxicity and cardiac events of unclear relationship to the study drugs. Thirty-one percent of treatment courses were complicated by grade 3 or 4 hematologic toxicity including one episode of hemolytic anemia. One patient developed interstitial pneumonitis. Two patients developed a decrease in left ventricular ejection fraction: one patient remained asymptomatic, but the other patient developed congestive heart failure. Although only 9% of patients had confirmed objective responses, 28% (5 of 18) of the patients with non-small cell lung cancer demonstrated biological activity (tumor regressions fulfilling the criteria for objective response on a single occasion but 3 patients lacking a follow-up measurement to document response duration) to this combination of mitomycin C and menadione. We conclude that further studies of chemomodulation in non-small cell lung cancer are appropriate.

Nelfinavir induces liposarcoma apoptosis through inhibition of regulated intramembrane proteolysis of SREBP-1 and ATF6.

Purpose: We previously reported that nelfinavir (NFV) induces G1 cell-cycle block and apoptosis selectively in liposarcoma cell lines due to increased SREBP-1 (sterol regulatory element binding protein-1) expression in the absence of increased transcription. We postulate that NFV interferes with regulated intramembrane proteolysis of SREBP-1 and ATF6 (activating transcription factor 6). Experimental Design: Time-lapse, confocal microscopic studies show that NFV inhibits the nuclear translocation of full-length SREBP-1–EGFP and ATF6–EGFP fusion proteins. siRNA-mediated knockdown of site-1 protease (S1P) and/or site-2 protease (S2P) leads to inhibition of SREBP-1 intracellular trafficking to the nucleus and reduces liposarcoma cell proliferation. Treatment of LiSa-2 liposarcoma cells with 3,4-dichloroisocoumarin, a serine protease inhibitor of S1P, did not affect SREBP-1 processing. In contrast, 1,10-phenanthroline, an S2P-specific inhibitor, reproduces the molecular and biological phenotypes observed in NFV-treated cells, which implicates S2P as a target of NFV. In vivo evaluation of NFV in a murine liposarcoma xenograft model leads to inhibition of tumor growth without significant toxicity. Results: NFV-induced upregulation of SREBP-1 and ATF6 results from inhibition of S2P, which together with S1P mediates regulated intramembrane proteolysis from their precursor to their transcriptionally active forms. The resulting endoplasmic reticulum (ER) stress and concurrent inhibition of the unfolded protein response induce caspase-mediated apoptosis. Conclusions: These results provide new insight into the mechanism of NFV-mediated induction of ER stress and cell death in liposarcomas and are the first to report targeting S2P for cancer therapy. Clin Cancer Res; 17(7); 1796–806. ©2011 AACR.

Mitomycin C and menadione for the treatment of advanced gastrointestinal cancers: a phase II trial

A phase II trial of menadione (2.5 g/m2 as a continuous intravenous infusion over 48 h) followed by mitomycin C (10–20 mg/m2 i.v. bolus) administered every 4–6 weeks was performed in 43 patients with advanced gastrointestinal cancer. Menadione, a vitamin K analog that lowers intracellular pools of reduced glutathione, was combined with mitomycin C in an attempt to overcome thiol-mediated resistance to alkylating-agent chemotherapy. The median age of patients entered on this trial was 58 years; performance status ranged from 60%–100%. None of the 43 evaluable patients obtained an objective response to this combination regimen. Median survival was 6.6 months. Treatment with menadione and mitomycin C was reasonably well tolerated except for hematological toxicity. A total of 27% of treatment courses were complicated by grade 3 or 4 hematological toxicity including one episode of hemolytic anemia and one episode of hemolytic uremic syndrome. One patient developed irreversible interstitial pneumonitis, and 1 patient had an asymptomatic decrease in the left0ventricular ejection fraction. Despite preclinical evidence indicating that menadione pretreatment enhances the cytotoxicity of mitomycin C, our study documents the resistance of advanced gastrointestinal cancers, particularly colorectal cancer, to mitomycin C modulated by menadione.

Phase I trial of intraperitoneal gemcitabine in the treatment of advanced malignancies primarily confined to the peritoneal cavity

Purpose: To determine the maximally tolerated dose, toxicity, and pharmacokinetics of i.p. gemcitabine. Experimental Design: Patients had peritoneal carcinomatosis. Gemcitabine (40, 80, 120, or 160 mg/m2) was administered into the peritoneal cavity in 2 L of warmed saline on days 1, 4, 8, and 12 of a 28-day cycle. Results: Thirty patients received 63 (median, 2; range, 0-6) courses. Tumors included ovary (14), uterus (2), colon (6), pancreas (3), and others (5). Dose-limiting toxicity included nausea, vomiting, diarrhea, dyspnea, fatal respiratory failure, and grade 3 elevation of alanine aminotransferase in three patients. Hematologic toxicity and pain were ≤grade 2. Three patients had decreased or resolved ascites. Of 19 patients evaluable for response, 10 had stable disease (median, 3.5 courses) and 9 had progressive disease. The median peak peritoneal concentration was 1,116-fold (range, 456-1,886) higher than the peak plasma level. Plasma and peritoneal levels were undetectable within 8 to 12 h. At 120 mg/m2, the median peritoneal area under the concentration versus time curve (AUC) was 82,612 ng/mL × h (range, 53,296-199,830) and the plasma AUC was 231 ng/mL × h (range, 47.6-259.5). The mean peritoneal advantage (AUCperitoneal/AUCplasma) was 847 (range, 356-1,385). Conclusions: I.p. administration of gemcitabine is tolerated within the tested dosage range. Technical problems with the Porta-Cath device and i.p. therapy per se may have been exacerbated by the enrollment of many patients with a variety of advanced i.p. diseases. Given the significant increase in local dose intensity and the documented activity of this drug, this agent may be an excellent candidate for i.p. therapy in optimally debulked ovarian cancer, either alone or in combination.

High-dose paclitaxel in combination with doxorubicin, cyclophosphamide and peripheral blood progenitor cell rescue in patients with high-risk primary and responding metastatic breast carcinoma: toxicity profile, relationship to paclitaxel pharmacokinetics and short-term outcome.

We assessed the feasibility and pharmacokinetics of high-dose infusional paclitaxel in combination with doxorubicin, cyclophosphamide, and peripheral blood progenitor cell rescue. Between October 1995 and June 1998, 63 patients with high-risk primary [stage II with ≥ 10 axillary nodes involved, stage IIIA or stage IIIB inflammatory carcinoma (n = 53)] or with stage IV responsive breast cancer (n = 10) received paclitaxel 150–775 mg/m2infused over 24 hours, doxorubicin 165 mg/m2as a continuous infusion over 96 hours, and cyclophosphamide 100 mg kg–1. There were no treatment-related deaths. Dose-limiting toxicity was reversible, predominantly sensory neuropathy following administration of paclitaxel at the 775 mg/m2dose level. Paclitaxel pharmacokinetics were non-linear at higher dose levels; higher paclitaxel dose level, AUC, and peak concentrations were associated with increased incidence of paraesthesias. No correlation between stomatitis, haematopoietic toxicities, and paclitaxel dose or pharmacokinetics was found. Kaplan–Meier estimates of 30-month event-free and overall survival for patients with primary breast carcinoma are 65% (95% CI; 51–83%) and 77% (95% CI; 64–93%). Paclitaxel up to 725 mg/m2infused over 24 hours in combination with with doxorubicin 165 mg/m2and cyclophosphamide 100 mg kg–1is tolerable. A randomized study testing this regimen against high-dose carboplatin, thiotepa and cyclophosphamide (STAMP V) is currently ongoing.

Nelfinavir inhibits regulated intramembrane proteolysis of sterol regulatory element binding protein‐1 and activating transcription factor 6 in castration‐resistant prostate cancer

Nelfinavir induces apoptosis in liposarcoma by inhibiting site‐2 protease (S2P) activity, which leads to suppression of regulated intramembrane proteolysis. We postulate similar effects in castration‐resistant prostate cancer because it exhibits a lipogenic phenotype. Nelfinavir inhibited androgen receptor activation in androgen‐sensitive prostate cancer and the nuclear translocation of the fusion proteins sterol regulatory element binding protein‐1 (SREBP‐1)–enhanced green fluorescence protein (EGFP) and activating transcription factor 6 (ATF6)–EGFP in castration‐resistant prostate cancer cells, viewed under confocal microscopy. Nelfinavir and site‐1 protease (S1P) and S2P small interfering RNAs (siRNAs) reduced the proliferation of castration‐resistant prostate cancer and induced apoptosis, which was opposed by autophagy. Inhibition of autophagy with hydroxychloroquine was additive to the apoptotic effect of nelfinavir. Western blotting of S1P and S2P siRNA knockdown and/or nelfinavir‐treated cells confirmed the accumulation of precursor SREBP‐1 and ATF6. 3,4‐Dichloroisocoumarin, an S1P inhibitor, did not affect SREBP‐1 processing. In contrast, 1,10‐phenanthroline, an S2P inhibitor, reproduced the nelfinavir‐treated molecular and biological phenotype. Nelfinavir‐mediated inhibition of regulated intramembrane proteolysis led to the accumulation of unprocessed SREBP‐1 and ATF6. This resulted in sequential endoplasmic reticulum stress, inhibition of the unfolded protein response, reduced fatty acid synthase expression and apoptosis, which was countered by autophagy. Inhibition of autophagy was at least additive to this pro‐apoptotic effect. These findings provide new insights into nelfinavir‐induced endoplasmic reticulum stress and cancer cell death, and lead us to propose investigating its clinical activity in castration‐resistant prostate cancer. This report validates S2P as a therapeutic target in castration‐resistant prostate cancer.

Predictors of long-term outcome following high-dose chemotherapy in high-risk primary breast cancer

We report on a predictive model of long-term outcome in 114 high-risk breast cancer patients treated with high-dose chemotherapy between 1989 and 1994. Paraffin-blocks from 90 of the 114 primaries were assessed for the presence of five risk factors: grade, mitotic index, protein expression of p53, HER2/neu, and oestrogen/progesterone receptor status; we could analyse the effect of risk factors in 84 of these 90 tumours. Seven-year relapse-free and overall survival was 58% (95% confidence interval 44–74%) and 82% (95% confidence interval 71–94%) vs 33% (95% confidence interval 21–52%) and 41% (95% confidence interval 28–60%) for patients whose primary tumours displayed ⩾3 risk factors vs patients with ⩽2 risk factors. For the entire group of 168 high-risk breast cancer patients, inflammatory stage IIIB disease and involved post-mastectomy margins were associated with decreased relapse-free survival and overall survival; patients treated with non-doxorubicin containing standard adjuvant therapy experienced worse overall survival (RR, 2.08; 95% confidence interval 1.04 to 4.16; P=0.04), while adjuvant tamoxifen improved overall survival (RR, 0.65; 95% confidence interval 0.41–1.01; P=0.054). Future trial designs and patient selection for studies specific for high-risk breast cancer patients should include appropriate prognostic models. Validation of such models could come from recently completed randomised, prospective trials.

SARC009: Phase 2 study of dasatinib in patients with previously treated, high-grade, advanced sarcoma

Dasatinib exhibited activity in preclinical models of sarcoma. The Sarcoma Alliance for Research through Collaboration (SARC) conducted a multicenter, phase 2 trial of dasatinib in patients with advanced sarcoma.