Lower osteopontin plasma levels are associated with superior outcomes in advanced non-small-cell lung cancer patients receiving platinum-based chemotherapy: SWOG Study S0003.

PURPOSE: S0003 was a phase III trial of carboplatin/paclitaxel with or without the hypoxic cytotoxin tirapazamine in patients with advanced or metastatic non-small-cell lung cancer (NSCLC). We investigated the relationship between clinical outcomes and plasma levels of the hypoxia-associated protein osteopontin (OPN) in patients on this protocol. PATIENTS AND METHODS: Baseline plasma was obtained from 172 patients. In 56 patients, sequential plasma was obtained after one or two cycles. Concentrations of OPN, as well as plasminogen activator inhibitor-1 (PAI-1) and vascular endothelial growth factor (VEGF), were measured using enzyme-linked immunosorbent assay. Tumor expression of OPN was assessed by immunohistochemistry in 61 matched archival specimens. RESULTS: Patients with lower OPN levels (below the median) had a significantly superior overall survival compared with patients with higher levels, regardless of treatment arm (hazard ratio [HR] = 0.60, P = .002). A similar correlation was observed for progression-free survival (HR = 0.69, P = .02). When examined as a continuous variable, OPN maintained its significant association with both progression-free (HR = 1.05, P = .01) and overall survival (HR = 1.09, P < .0001). Patients with lower plasma OPN levels were significantly more likely to have tumor response (P = .03). No differences were observed between treatment arms. Tumor OPN levels did not correlate with patient outcomes or with plasma levels. No associations were observed between patient outcomes and VEGF or PAI-1 levels; however, plasma concentrations of these markers were significantly interrelated (P < .0001) and significantly decreased after treatment (P = .0002 and P = .03, respectively). CONCLUSION: Pretreatment plasma levels of OPN are significantly associated with patient response, progression-free survival, and overall survival in chemotherapy-treated patients with advanced NSCLC.

Bortezomib (PS-341) in relapsed or refractory extensive stage small cell lung cancer: a Southwest Oncology Group phase II trial (S0327).

BACKGROUND: In preclinical models, the proteasome inhibitor bortezomib (PS-341) inhibits the growth of small cell lung cancer (SCLC) by inhibiting the antiapoptotic Bcl-2 signaling pathway. We conducted a phase II trial of PS-341 in previously treated patients with platinum-sensitive and -refractory extensive stage SCLC to determine response rate, toxicity, and survival. METHODS: Patients with histologically confirmed SCLC, measurable disease, Zubrod performance status 0-1, and previous treatment with platinum-based therapy were enrolled. They were stratified by platinum-sensitivity status: sensitive (relapse >90 days after platinum) or refractory (progression during or < or =90 days after platinum). PS-341 was administered at 1.3 mg/m intravenously on days 1, 4, 8, and 11 every 21 days. RESULTS: Of 56 eligible patients, 28 were platinum sensitive and 28 refractory. Twenty-nine patients (52%) had received two or more previous chemotherapy regimens. One platinum-refractory patient had a confirmed partial response. A majority of assessable patients (91%) progressed. Median progression-free survival and overall survival were 1 month and 3 months, respectively. Ten patients (18%) discontinued treatment due to adverse events or side effects. CONCLUSION: Although PS-341 induced a response in a patient with platinum-refractory disease, it has limited single-agent activity in this heavily pretreated cohort. As shown in preclinical models, testing of PS-341 in combination with an apoptotic trigger such as chemotherapy, is a rational clinical approach. A trial of topotecan plus PS-341 has been initiated to test this concept.