Efficacy and safety of sunitinib in elderly patients with metastatic renal cell carcinoma.

BACKGROUND: We retrospectively analyzed sunitinib outcome as a function of age in metastatic renal cell carcinoma (mRCC) patients. METHODS: Data were pooled from 1059 patients in six trials. Kaplan-Meier estimates of progression-free survival (PFS) and overall survival (OS) were compared by log-rank test between patients aged <70 (n=857; 81%) and ≥70 (n=202; 19%) years. RESULTS: In first-line patients, median PFS was comparable in younger and older patients, 9.9 vs 11.0 months, respectively (HR, 0.89; 95% CI: 0.73-1.09; P=0.2629), as was median OS, 23.6 vs 25.6 months (HR, 0.93; 95% CI: 0.74-1.18; P=0.5442). Similarly, in cytokine-refractory patients, median PFS was 8.1 vs 8.4 months (HR, 0.79; 95% CI: 0.49-1.28; P=0.3350), while median OS was 20.2 vs 15.8 months (HR, 1.14; 95% CI: 0.73-1.79; P=0.5657). Some treatment-emergent adverse events were significantly less common in younger vs older patients, including fatigue (60% vs 69%), cough (20% vs 29%), peripheral edema (17% vs 27%), anemia (18% vs 25%), decreased appetite (13% vs 29%), and thrombocytopenia (16% vs 25%; all P<0.05). Hand-foot syndrome was more common in younger patients (32% vs 24%). CONCLUSIONS: Advanced age should not be a deterrent to sunitinib therapy and elderly patients may achieve additional clinical benefit.

A phase I study of sunitinib plus bevacizumab in advanced solid tumors.

PURPOSE: Bevacizumab is an antibody against vascular endothelial growth factor; sunitinib is an inhibitor of vascular endothelial growth factor and related receptors. The safety and maximum tolerated dose of sunitinib plus bevacizumab was assessed in this phase I trial. EXPERIMENTAL DESIGN: Patients with advanced solid tumors were treated on a 3+3 trial design. Patients received sunitinib daily (starting dose level, 25 mg) for 4 weeks on followed by 2 weeks off and bevacizumab (starting dose level, 5 mg/kg) on days 1, 15, and 29 of a 42-day cycle. Dose-limiting toxicities during the first 6-week cycle were used to determine the maximum tolerated dose. RESULTS: Thirty-eight patients were enrolled. Patients received a median of 3 cycles of treatment (range, 1-17(+)). There was one dose-limiting toxicity (grade 4 hypertension) at 37.5 mg sunitinib and 5 mg/kg bevacizumab. Grade 3 or greater toxicity was observed in 87% of patients including hypertension (47%), fatigue (24%), thrombocytopenia (18%), proteinuria (13%), and hand-foot syndrome (13%). Dose modifications and delays were common at higher dose levels. No clinical or laboratory evidence of microangiopathic hemolytic anemia was observed. Seven patients had a confirmed Response Evaluation Criteria in Solid Tumors-defined partial response (18%; 95% confidence interval, 8-34%). Nineteen of the 32 patients with a postbaseline scan (59%) had at least some reduction in overall tumor burden (median, 32%; range, 3-73%). CONCLUSIONS: The combination of sunitinib and bevacizumab in patients with advanced solid tumors is feasible, albeit with toxicity at higher dose levels and requiring dose modification with continued therapy. Antitumor activity was observed across multiple solid tumors.

Phase I trial of weekly docetaxel and daily temozolomide in patients with metastatic disease.

UNLABELLED: Docetaxel is second generation taxoid that has shown activity against a variety of cancers and has been approved for use in cancers of the breast, lung, head and neck, ovaries and prostate. Temozolomide is an alkylating agent which crosses the blood brain barrier and has demonstrated antitumor activity against a broad range of tumor types, including malignant glioma, melanoma, non small cell lung cancer and carcinoma of the ovary and colon. A Phase I trial was conducted to determine the toxicity of this combination in refractory solid tumor patients. METHODS: Twenty five patients with metastatic cancers were enrolled in a Phase I dose escalation trial. Docetaxel was administered weekly in 5 escalating doses of 25 to 35 mg/ m(2) as a one-hour bolus intravenous infusion for 3 consecutive weeks. Temozolamide was administered orally daily for 3 weeks (escalating doses of 75 to 100 mg/m(2)). Cycles were repeated at 4 week intervals. RESULTS: The maximum tolerated dose (MTD) was not determined in this study. The most commonly reported adverse events were mild to moderate nausea, vomiting and fatigue. Thrombocytopenia was the most commonly observed grade 3 and 4 hematological toxicity. Eight patients had dose interruptions for adverse events and only one patient had a dose reduction while receiving 30 mg/ m(2) of docetaxel and 90 mg/ m(2) of temozolomide due to grade 3 thrombocytopenia. Two patients achieved partial responses and 88% of the patients are deceased. The median survival is 8.4 months. CONCLUSIONS: The combination of docetaxel and temozolomide was well tolerated and these agents can be safely combined. For phase II trials, docetaxel 35 mg/ m(2) IV day 1, 8 and 15, and daily temozolomide at 100 mg/ m(2) day 1-21 are recommended.

Prognostic factors associated with long-term survival in previously untreated metastatic renal cell carcinoma.

PURPOSE: To identify prognostic factors (PF) for long-term survival in metastatic renal cell carcinoma (RCC) patients. METHODS: We retrospectively reviewed a metastatic RCC database at the Cleveland Clinic Foundation consisting of 358 previously untreated patients who were enrolled in institutional review board-approved clinical trials of immunotherapy and/or chemotherapy at our institution from 1987 to 2002. In order to identify patient characteristics associated with long-term survival, we compared 226 'short-term' survivors [defined as overall survival (OS) <2 years] with 31 'long-term' survivors (OS >or=5 years). RESULTS: Using logistic regression models, four adverse PF were identified as independent predictors of long-term survival: hemoglobin less than the lower limit of normal, greater than two metastatic sites, involved kidney (left), and Eastern Cooperative Oncology Group (ECOG) performance status (PS). Using the number of poor prognostic features present, three distinct risk groups could be identified. Patients with 0 or 1 adverse prognostic feature present had an observed likelihood of long-term survival of 32% (21/66) compared with 9% (8/91) for patients with two adverse features present and only 1% (1/93) for patients with more than two adverse features. CONCLUSIONS: Independent predictors of long-term survival in previously untreated metastatic RCC include baseline hemoglobin level, number of involved sites, involved kidney, and ECOG PS. Incorporation of these factors into a simple prognostic scoring system enables three distinct groups of patients to be identified.

Downregulation of topoisomerase IIbeta in myeloid leukemia cell lines leads to activation of apoptosis following all-trans retinoic acid-induced differentiation/growth arrest.

Among the topoisomerase (topo) II isozymes (alpha and beta), topo IIbeta has been suggested to regulate differentiation. In this study, we examined the role of topo IIbeta in all-trans retinoic acid (ATRA)-induced differentiation of myeloid leukemia cell lines. Inhibition of topo IIbeta activity or downregulation of protein expression enhanced ATRA-induced differentiation/growth arrest and apoptosis. ATRA-induced apoptosis in topo IIbeta-deficient cells involved activation of the caspase cascade and was rescued by ectopic expression of topo IIbeta. Gene expression profiling led to the identification of peroxiredoxin 2 (PRDX2) as a candidate gene that was downregulated in topo IIbeta-deficient cells. Reduced expression of PRDX2 validated at the mRNA and protein level, in topo IIbeta-deficient cells correlated with increased accumulation of reactive oxygen species (ROS) following ATRA-induced differentiation. Overexpression of PRDX2 in topo IIbeta-deficient cells led to reduced accumulation of ROS and partially reversed ATRA-induced apoptosis. These results support a role for topo IIbeta in survival of ATRA-differentiated myeloid leukemia cells. Reduced expression of topo IIbeta induces apoptosis in part by impairing the anti-oxidant capacity of the cell owing to downregulation of PRDX2. Thus, suppression of topo IIbeta and/or PRDX2 levels in myeloid leukemia cells provides a novel approach for improving ATRA-based differentiation therapy.

Phase I trial of phenoxodiol delivered by continuous intravenous infusion in patients with solid cancer.

BACKGROUND: Phenoxodiol is a multi-pathway initiator of apoptosis with broad anti-tumor activity and high specificity for tumor cells. Its biochemical effects are particularly suited to reversal of chemo-resistance, and the drug is being developed as a chemo-sensitizer of standard chemotherapeutics in solid cancers. This phase I, single-center trial was conducted to test a continuous intravenous dosing regimen of phenoxodiol in patients with late-stage, solid tumors to determine toxicity, pharmacokinetics, and preliminary efficacy. METHODS: Phenoxodiol given by intravenous infusion continuously for 7 days on 14-day cycles was dose-escalated on an inter-patient basis at dosages of 0.65,1.3, 3.3, 20.0, and 27.0 mg/kg/day (three to four patients per stratum). Treatment cycles continued until disease progression. Toxicity was based on standard criteria; efficacy was based on changes in tumor burden (WHO); pharmacokinetic analysis was conducted on plasma samples at specified time points during treatment cycles. RESULTS: Nineteen heavily-pre-treated patients with solid tumors received a median of three cycles of treatment (range 1-13); two patients received >or= 12 cycles. No dose-limiting toxicities were encountered, with emesis and fatigue (one patient) and rash (one patient) the only significant toxicities. Stabilized disease was the best efficacy outcome, with one patient showing stable disease at 24 weeks. Pharmacokinetics suggested a linear relationship between dosage and mean steady-state plasma concentrations of phenoxodiol. CONCLUSION: A 7-day continuous infusion of phenoxodiol given every 2 weeks is well tolerated up to a dose of 27.0 mg/kg/day.

Synergistic growth inhibition by Iressa and Rapamycin is modulated by VHL mutations in renal cell carcinoma.

Epidermal growth factor receptor (EGFR) and tumour growth factor alpha (TGFalpha) are frequently overexpressed in renal cell carcinoma (RCC) yet responses to single-agent EGFR inhibitors are uncommon. Although von Hippel-Lindau (VHL) mutations are predominant, RCC also develops in individuals with tuberous sclerosis (TSC). Tuberous sclerosis mutations activate mammalian target of rapamycin (mTOR) and biochemically resemble VHL alterations. We found that RCC cell lines expressed EGFR mRNA in the near-absence of other ErbB family members. Combined EGFR and mTOR inhibition synergistically impaired growth in a VHL-dependent manner. Iressa blocked ERK1/2 phosphorylation specifically in wt-VHL cells, whereas rapamycin inhibited phospho-RPS6 and 4E-BP1 irrespective of VHL. In contrast, phospho-AKT was resistant to these agents and MYC translation initiation (polysome binding) was similarly unaffected unless AKT was inhibited. Primary RCCs vs cell lines contained similar amounts of phospho-ERK1/2, much higher levels of ErbB-3, less phospho-AKT, and no evidence of phospho-RPS6, suggesting that mTOR activity was reduced. A subset of tumours and cell lines expressed elevated eIF4E in the absence of upstream activation. Despite similar amounts of EGFR mRNA, cell lines (vs tumours) overexpressed EGFR protein. In the paired cell lines, PRC3 and WT8, EGFR protein was elevated post-transcriptionally in the VHL mutant and EGF-stimulated phosphorylation was prolonged. We propose that combined EGFR and mTOR inhibitors may be useful in the subset of RCCs with wt-VHL. However, apparent differences between primary tumours and cell lines require further investigation.

Oral capecitabine vs intravenous 5-fluorouracil and leucovorin: integrated efficacy data and novel analyses from two large, randomised, phase III trials.

This study evaluates the efficacy of capecitabine using data from a large, well-characterised population of patients with metastatic colorectal cancer (mCRC) treated in two identically designed phase III studies. A total of 1207 patients with previously untreated mCRC were randomised to either oral capecitabine (1250 mg m(-2) twice daily, days 1-14 every 21 days; n=603) or intravenous (i.v.) bolus 5-fluorouracil/leucovorin (5-FU/LV; Mayo Clinic regimen; n=604). Capecitabine demonstrated a statistically significant superior response rate compared with 5-FU/LV (26 vs 17%; P<0.0002). Subgroup analysis demonstrated that capecitabine consistently resulted in superior response rates (P<0.05), even in patient subgroups with poor prognostic indicators. The median time to response and duration of response were similar and time to progression (TTP) was equivalent in the two arms (hazard ratio (HR) 0.997, 95% confidence interval (CI) 0.885-1.123, P=0.95; median 4.6 vs 4.7 months with capecitabine and 5-FU/LV, respectively). Multivariate Cox regression analysis identified younger age, liver metastases, multiple metastases and poor Karnofsky Performance Status as independent prognostic indicators for poor TTP. Overall survival was equivalent in the two arms (HR 0.95, 95% CI 0.84-1.06, P=0.48; median 12.9 vs 12.8 months, respectively). Capecitabine results in superior response rate, equivalent TTP and overall survival, an improved safety profile and improved convenience compared with i.v. 5-FU/LV as first-line treatment for MCRC. For patients in whom fluoropyrimidine monotherapy is indicated, capecitabine should be strongly considered. Following encouraging results from phase I and II trials, randomised trials are evaluating capecitabine in combination with irinotecan, oxaliplatin and radiotherapy. Capecitabine is a suitable replacement for i.v. 5-FU as the backbone of colorectal cancer therapy.

A phase I trial of weekly gemcitabine and subcutaneous interferon alpha in patients with refractory renal cell carcinoma.

INTRODUCTION: Recombinant human interferon-a2b (rHuIFN-alpha2b) and Interleukin-2 have limited effectiveness in the treatment of metastatic renal cell carcinoma (MRCC). Gemcitabine (Gemzar) is also reported to have activity against MRCC, and recent in vitro, in nude mice xenografts, and human data suggests increased activity of gemcitabine (Gemzar) when combined with IFN-alpha2b. PURPOSE: A phase I clinical trial utilizing gemcitabine (Gemzar and rHuIFN-alpha2b was conducted in patients with metastatic renal cell carcinoma. METHODS: Treatment consisted of: gemcitabine (Gemzar) 600 mg/m2 I.V. weekly and rHuIFN-alpha2b 1.0 MU/m2 (dose level A) or 3.0MU/m2 S.C. (dose level B) three times a week for 6 weeks with a 2 weeks rest period. RESULTS: Thirteen patients were entered into the trial and were evaluated. Dose limiting toxicity was predominantly hematologic, and was seen at dose level B. This included grade 3 anemia (1 patient), neutropenia (1 patient), and nausea (1 patient) and grade 4 neutropenia (1 patient). The maximal tolerated dose was gemcitabine (Gemzar) 600 mg/m2 I.V. weekly and rHuIFN-alpha2b 1.0 MU/m2 three times a week. CONCLUSION: This combination of gemcitabine (Gemzar) and rHuIFN-alpha2b has significant hematologic toxicity despite low doses of each agent. Further investigation of this combination using this schedule is not recommended.

Phase I trial of simultaneously administered GM-CSF and IL-6 in patients with renal-cell carcinoma: clinical and laboratory effects.

BACKGROUND: Metastatic renal-cell carcinoma is a neoplasm that is minimally responsive to cytotoxic chemotherapy. Tumor regression following therapy with cytokines such as interferon alpha and or interleukin-2 is seen in selected subsets of patients. Investigations with other immunomodulatory cytokines, such as GM-CSF and IL-6 are therefore of interest. PATIENTS AND METHODS: A phase I trial of concomitantly administered granulocyte macrophage-colony stimulating factor (3.0 mcg/kg/day s.c. d1-14) and escalating doses of interleukin-6 (1.0, 5.0 or 10.0 microg/kg/day d1-14) was conducted in patients with metastatic renal-cell carcinoma to explore the toxicity of the combination and its hematologic effects. RESULTS: The most common side effects seen were fever, fatigue and arthralgias. Dose limiting toxicity included thrombocytosis and hyperbilirubinemia in patients receiving 10 microg/kg/day of IL-6. The hematologic effects of IL-6 and GM-CSF included leukocytoses and thrombocytosis, with increases in peripheral blood progenitors (BFU-E, CFU-GM, and CFU-GEMM). Evidence of platelet activation demonstrated by increased platelet expression of CD62 was found. No clinical responses were observed. CONCLUSIONS: The combination of IL-6 and GM-CSF has pleotropic hematologic effects. Further studies with this combination for the treatment of renal-cell carcinoma are not recommended.

Cytokine therapy for metastatic renal cell carcinoma.

Cytokine therapy for patients with metastatic renal cancer is based on observations suggesting this neoplasm may be responsive to immunotherapy. Two cytokines, interferon-alpha (IFN-alpha) and interleukin 2 (IL-2) produce tumor regressions in 10% to 15% of patients with metastatic disease. Randomized trials demonstrate a modest survival advantage for patients treated with IFN-alpha. Combinations of IL-2 and IFN-alpha appear to be associated with improved response rates, but no demonstrable effect on survival. Additions of other cytokines (eg, GM-CSF) or chemotherapy to this combination has been investigated, but results do not suggest they enhance the outcome. Patient selection remains an important issue in this patient population. Individuals who are asymptomatic and have limited pulmonary or soft-tissue disease are most likely to benefit. The roles of immune dysregulation and the addition of novel cytostatic agents to these regimens are under investigation.

Phase I and II trials of subcutaneously administered rIL-2, interferon alfa-2a, and fluorouracil in patients with metastatic renal carcinoma.

PURPOSE: A phase I followed by a phase II trial utilizing rIL-2, IFN alpha, and 5-FU were conducted in patients with unresectable and/or metastatic renal cell carcinoma. METHODS: Treatment consisted of: rIL-2 at 5.0 x 10(6) IU/m2 SQ on days 1-5 for 4 weeks, rHUIFN alpha-2a at 5.0 x 10(6) U/m2 SQ on days 1, 3, and 5 for 4 weeks, and 5-FU by IV bolus on days 1-5 during week 1. In the phase I study, patients were treated at varying doses of 5-FU: I-none, II-250 mg/m2, III-300, and IV 375. A phase II trial was then conducted utilizing the same schedule and maximum tolerated dose (MTD) for 5-FU. RESULTS: Twenty patients were entered into the phase I trial. Dose-limiting toxicity included grade III nausea and vomiting, and one sudden cardiac death. The MTD for 5-FU was determined to be 300 mg/m2. In the phase II trial, a median of two cycles of therapy was administered to 25 evaluable patients. Toxicity was moderate and consisted primarily of fevers, chills, fatigue, nausea/vomiting, and anorexia. Grade IV thrombocytopenia, consistent with ITP, developed in one patient each on the phase I and phase II trial. Seven partial responses were seen among 25 patients treated in the phase II trial for a 28% (CI 12-49%) response rate. CONCLUSIONS: The addition of 5-FU to rIL-2 and rHuIFN alpha-2a appears to increase the toxicity of this therapy. Randomized trials will be required to determine if efficacy is enhanced.

Randomized multicenter phase II trial of subcutaneous recombinant human interleukin-12 versus interferon-alpha 2a for patients with advanced renal cell carcinoma.

Recombinant human interleukin-12 (rHuIL-12) is a pleiotropic cytokine with anticancer activity against renal cell carcinoma (RCC) in preclinical models and in a phase I trial. A randomized phase II study of rHuIL-12 compared with interferon-alpha (IFN-alpha) evaluated clinical response for patients with previously untreated, advanced RCC. Patients were randomly assigned 2:1 to receive either rHuIL-12 or IFN-alpha2a. rHuIL-12 was administered by subcutaneous (s.c.) injection on days 1, 8, and 15 of each 28-day cycle. The dose of IL-12 was escalated during cycle 1 to a maintenance dose of 1.25 microg/kg. IFN was administered at 9 million units by s.c. injection three times per week. Serum concentrations of IL-12, IFN-gamma, IL-10, and neopterin were obtained in 10 patients treated with rHuIL-12 after the first full dose of 1.25 microg/kg given on day 15 (dose 3) of cycle 1 and again after multiple doses on day 15 (dose 6) of cycle 2. Thirty patients were treated with rHuIL-12, and 16 patients were treated with IFN-alpha. Two (7%) of 30 patients treated with rHuIL-12 achieved a partial response, and the trial was closed to accrual based on the low response proportion. IL-12 was absorbed rapidly after s.c. drug administration, with the peak serum concentration appearing at approximately 12 h in both cycles. Serum IL-12 concentrations remained stable on multiple dosing. Levels of IFN-gamma, IL-10, and neopterin increased with rHuIL-12 and were maintained in cycle 2. rHuIL-12 is a novel cytokine with unique pharmacologic and pharmacodynamic features under study for the treatment of malignancy and other medical conditions. The low response proportion associated with rHuIL-12 single-agent therapy against metastatic RCC was disappointing, given the preclinical data. Further study of rHuIL-12 for other medical conditions is underway. For RCC, the study of new cytokines is of the highest priority.

Tumor-induced sensitivity to apoptosis in T cells from patients with renal cell carcinoma: role of nuclear factor-kappaB suppression.

Antitumor immunity fails to adequately develop in many cancer patients, including those with renal cell carcinoma (RCC). A number of different mechanisms have been proposed to explain the immune dysfunction observed in cancer patient T cells. Here we show that T cells from RCC patients display increased sensitivity to apoptosis. Tumor-infiltrating lymphocytes (TILs) display the most profound sensitivity, because 10-15% of those cells are apoptotic when assessed by terminal deoxynucleotidyltransferase-mediated nick end labeling in situ, and the number of apoptotic TILs further increases after 24 h of culture. Peripheral blood T cells from RCC patients are not directly apoptotic, although T lymphocytes derived from 40% of those individuals undergo activation-induced cell death (AICD) upon in vitro stimulation with phorbol myristate acetate and ionomycin. This is in contrast to T cells from normal individuals, which are resistant to AICD. TILs and peripheral blood T cells from RCC patients also exhibit impaired activation of the transcription factor, nuclear factor (NF)-kappaB. Additional findings presented here indicate that the heightened sensitivity of patient T cells to apoptosis may be tumor induced, because supernatants from RCC explants sensitize, and in some instances directly induce, normal T cells to apoptosis. These same supernatants also inhibit NF-kappaB activation. RCC-derived gangliosides may represent one soluble tumor product capable of sensitizing T cells to apoptosis. Pretreatment with neuraminidase, but not proteinase K, abrogated the suppressive effects of tumor supernatants on both NF-kappaB activation and apoptosis. Additionally, gangliosides isolated from tumor supernatants not only inhibited NF-kappaB activation but also sensitized T cells to AICD. These findings demonstrate that tumor-derived soluble products, including gangliosides, may contribute to the immune dysfunction of T cells by altering their sensitivity to apoptosis.

Cell cycle phase specificity in the potentiation of etoposide-induced DNA damage and apoptosis by KN-62, an inhibitor of calcium-calmodulin-dependent enzymes.

The cell cycle phase-dependent induction of DNA damage and apoptosis by etoposide (VP-16) and its modulation by 1-[N,O-bis(1, 5-isoquinolinesulfonyl)-N-methyl-l-tyrosyl]-4-piperazine (KN-62), an inhibitor of calcium-calmodulin-dependent enzymes, were examined in sensitive (HL-60/S) and VP-16-resistant (HL-60/DOX0.05) HL-60 cells. Cells from exponential-phase cultures were enriched by centrifugal elutriation into G(1), S, and G(2)+M fractions. Modulation of VP-16-induced apoptosis by KN-62 in HL-60/S cells was apparent only in the S phase at the IC(50) concentration. However, in the HL-60/DOX0.05 cells, significant (P < 0.001) potentiation of VP-16-induced apoptosis by a non-cytotoxic concentration of 2 microM KN-62 was apparent in cells in the G(1), S, and G(2)+M phases, as well as over the entire concentration range tested. VP-16-induced apoptosis and its potentiation by a non-cytotoxic concentration of 2 microM KN-62 were correlative with drug-stabilized DNA cleavable complex formation based on a band depletion assay. In agreement with the results on apoptosis in the resistant HL-60/DOX0.05 cells, the enhanced depletion of the alpha and beta isoforms of topoisomerase II by VP-16 + KN-62 was observed in G(1), S, and G(2)+M cells. Results suggest that the effects of KN-62 in reversing resistance are based on its role as a potent sensitizer of VP-16-induced DNA damage and apoptosis in a cell cycle phase-independent manner.

Roles of NF-kappaB and 26 S proteasome in apoptotic cell death induced by topoisomerase I and II poisons in human nonsmall cell lung carcinoma.

Activation of signaling pathways after DNA damage induced by topoisomerase (topo) poisons can lead to cell death by apoptosis. Treatment of human nonsmall cell lung carcinoma (NSCLC-3 or NSCLC-5) cells with the topo I poison SN-38 or the topo II poison etoposide (VP-16) leads to activation of NF-kappaB before induction of apoptosis. Inhibiting the degradation of IkappaBalpha by pretreatment with the proteasome inhibitor MG-132 significantly inhibited NF-kappaB activation and apoptosis but not DNA damage induced by SN-38 or VP-16. Transfection of NSCLC-3 or NSCLC-5 cells with dominant negative mutant IkappaBalpha (mIkappaBalpha) inhibited SN-38 or VP-16 induced transcription and DNA binding activity of NF-kappaB without altering drug-induced apoptosis. Regulation of apoptosis by mitochondrial release of cytochrome c and activation of pro-caspase 9 followed by cleavage of poly(ADP-ribose) polymerase by effector caspases 3 and 7 was similar in neo and mIkappaBalpha cells treated with SN-38 or VP-16. In contrast to pretreatment with MG-132, exposure to MG-132 after SN-38 or VP-16 treatment of neo or mIkappaBalpha cells decreased cell cycle arrest in the S/G2 + M fraction and enhanced apoptosis compared with drug alone. In summary, apoptosis induced by topoisomerase poisons in NSCLC cells is not mediated by NF-kappaB but can be manipulated by proteasome inhibitors.

A phase II pharmacodynamic study of pyrazoloacridine in patients with metastatic colorectal cancer.

PURPOSE: To perform a phase II trial of pyrazoloacridine (PZA), a novel DNA intercalator, in patients with metastatic colorectal carcinoma and no previous therapy. METHODS: PZA was administered at a dose of 750 mg/m2 intravenously over 3 h every 21 days. Pharmacokinetic studies to determine PZA plasma concentrations were performed. RESULTS: No responses were seen in 14 response-evaluable patients. Patients received a median of two cycles of PZA (range 1-6). Toxicity included neutropenia and neurologic side-effects, which were > or = grade III in 73% and 14%, respectively. High plasma concentrations of PZA (Cmax) correlated with low neutrophil counts (P = 0.04). CONCLUSIONS: PZA is inactive at this dose and schedule in colorectal cancer, and produces moderately severe toxicity.

Phase 1 trial of subcutaneous IL-6 in patients with refractory cancer: clinical and biologic effects.

The authors evaluated the clinical and biologic effects of human recombinant interleukin-6 (rhIL-6) in patients with refractory cancer. A phase 1 trial using escalating doses of rhIL-6 (1-50 microg x kg(-1) x d(-1), Monday through Friday for 4 weeks) was performed in 30 patients. Toxicity was moderate and the maximum tolerated dose was determined to be 25 microg x kg(-1)x d(-1) based on cardiac and neurocortical toxicity in one patient each and thrombocytosis (platelets > 800,000/microL) in three patients. One patient with non-small-cell lung cancer had a partial response after three cycles of therapy. The biologic effects of rhIL-6 included anemia and dose-related thrombocytosis. Various proinflammatory activities were induced and included dose-related cyclical increases in peripheral blood monocytes and the CD14+/CD45RB+ +/- CD16C+ mononuclear cell populations. These increases were accompanied by increased levels of C-reactive protein, serum neopterin, and type I soluble tumor necrosis factor receptor. In contrast, rhIL-6 did not affect lymphocyte numbers or function (cytotoxicity, cytokine levels, immunoglobulin levels), with the possible exception of IL-2Ralpha mRNA induction in peripheral blood lymphocytes. rhIL-6 has pleiotropic proinflammatory actions in vivo and moderate toxicity when administered as long-term therapy.

Cytokine combinations: therapeutic use in patients with advanced renal cell carcinoma.

Treatment of metastatic renal cell carcinoma (RCC) remains unsatisfactory. To enhance the antitumor effects of various cytokines, combinations of these agents have been investigated. Interleukin-2 (IL-2) and interferon-alfa (IFN-alpha) have been combined based on data from preclinical studies suggesting synergism. A review of available phase I and II trials in more than 1,400 patients indicates that response rates are approximately 20%. Complete regressions are seen in 3% to 5% of patients. To demonstrate that this combination increases overall response rates, randomized trials were required. The results of a phase III study demonstrate a significantly improved response rate (18.6%) and 1-year event-free survival (20.9%) for patients treated with continuous infusion recombinant (r) IL-2 and subcutaneous IFN-alpha compared with either cytokine alone. The toxicity of rlL-2 and IFN-alpha is related to cytokine dose and schedule, but appears less than that reported with high-dose rIL-2. Analysis of prognostic factors and surrogate marker changes have been conducted. Performance status and number of disease sites predict response. rIL-2 and IFNalpha were then combined with fluorouracil, with initial reports suggesting response rates greater than 40%. Recent reports indicate 1% to 39% of patients responding. In a group of 836 patients with metastatic RCC receiving this therapy, 25.3% responded. Randomized trials comparing chemoimmunotherapy to rIL-2 and/or IFN-alpha are now required. The biologic basis and rationale for utilization of cytokines are strong. Clinical results are consistent with improved response rates in patients receiving rIL-2 and IFN-alpha. Continued investigation of novel and new treatment approaches remains a priority.