Dacomitinib versus erlotinib in patients with advanced-stage, previously treated non-small-cell lung cancer (ARCHER 1009): a randomised, double-blind, phase 3 trial.

BACKGROUND: Dacomitinib is an irreversible pan-EGFR family tyrosine kinase inhibitor. Findings from a phase 2 study in non-small cell lung cancer showed favourable efficacy for dacomitinib compared with erlotinib. We aimed to compare dacomitinib with erlotinib in a phase 3 study. METHODS: In a randomised, multicentre, double-blind phase 3 trial in 134 centres in 23 countries, we enrolled patients who had locally advanced or metastatic non-small-cell lung cancer, progression after one or two previous regimens of chemotherapy, Eastern Cooperative Oncology Group (ECOG) performance status of 0-2, and presence of measurable disease. We randomly assigned patients in a 1:1 ratio to dacomitinib (45 mg/day) or erlotinib (150 mg/day) with matching placebo. Treatment allocation was masked to the investigator, patient, and study funder. Randomisation was stratified by histology (adenocarcinoma vs non-adenocarcinoma), ethnic origin (Asian vs non-Asian and Indian sub-continent), performance status (0-1 vs 2), and smoking status (never-smoker vs ever-smoker). The coprimary endpoints were progression-free survival per independent review for all randomly assigned patients, and for all randomly assigned patients with KRAS wild-type tumours. The study has completed accrual and is registered with ClinicalTrials.gov, number NCT01360554. FINDINGS: Between June 22, 2011, and March 12, 2013, we enrolled 878 patients and randomly assigned 439 to dacomitinib (256 KRAS wild type) and 439 (263 KRAS wild type) to erlotinib. Median progression-free survival was 2·6 months (95% CI 1·9-2·8) in both the dacomitinib group and the erlotinib group (stratified hazard ratio [HR] 0·941, 95% CI 0·802-1·104, one-sided log-rank p=0·229). For patients with wild-type KRAS, median progression-free survival was 2·6 months for dacomitinib (95% CI 1·9-2·9) and erlotinib (95% CI 1·9-3·0; stratified HR 1·022, 95% CI 0·834-1·253, one-sided p=0·587). In patients who received at least one dose of study drug, the most frequent grade 3-4 adverse events were diarrhoea (47 [11%] patients in the dacomitinib group vs ten [2%] patients in the erlotinib group), rash (29 [7%] vs 12 [3%]), and stomatitis (15 [3%] vs two [<1%]). Serious adverse events were reported in 52 (12%) patients receiving dacomitinib and 40 (9%) patients receiving erlotinib. INTERPRETATION: Irreversible EGFR inhibition with dacomitinib was not superior to erlotinib in an unselected patient population with advanced non-small-cell lung cancer or in patients with KRAS wild-type tumours. Further study of irreversible EGFR inhibitors should be restricted to patients with activating EGFR mutations. FUNDING: Pfizer.

Efficacy and safety of ofatumumab and bendamustine followed by ofatumumab maintenance in patients with relapsed indolent non-Hodgkin lymphoma after prior rituximab.

In indolent non-Hodgkin's lymphoma (iNHL), patients treated with rituximab, alone or in combination with various chemotherapeutic agents eventually relapse. This study evaluated the combination of ofatumumab and bendamustine, followed by maintenance ofatumumab in patients with relapsed iNHL with prior sensitivity to rituximab. Among the 49 patients enrolled, 24.5% achieved a complete response (CR) and 42.9% achieved a partial response (PR), with an overall response rate of 67.3% at the end of the induction therapy. Additionally, six patients with PR during induction phase achieved CR during the maintenance phase. Treatment-related adverse event was observed in 95.9% patients. The most common hematologic and biochemical abnormalities were decrease in lymphocytes (85.7%) and increase in glucose (91.8%), respectively. Overall, 42.9% progressed and 14.3% died during the study. Thus, ofatumumab in combination with bendamustine, followed by ofatumumab maintenance, was effective in the treatment of patients with iNHL with a manageable safety profile (NCT01294579).

Ublituximab plus ibrutinib versus ibrutinib alone for patients with relapsed or refractory high-risk chronic lymphocytic leukaemia (GENUINE): a phase 3, multicentre, open-label, randomised trial.

BACKGROUND: Patients with chronic lymphocytic leukaemia and high-risk features have poorer outcomes on ibrutinib than those without high-risk features. The aim of this study was to assess the benefit of adding ublituximab, an anti-CD20 monoclonal antibody, to ibrutinib therapy in this population. METHODS: We did a randomised, phase 3, multicentre study (GENUINE) of patients aged 18 years or older with relapsed or refractory chronic lymphocytic leukaemia with at least one of 17p deletion, 11q deletion, or TP53 mutation, at 119 clinics in the USA and Israel. Eligible patients had received at least one previous chronic lymphocytic leukaemia therapy and had an Eastern Cooperative Oncology Group performance status of 2 or lower. We randomised patients (1:1) using permuted block randomisation with a block size of four and stratified by previous lines of therapy (one vs two or more) to receive ibrutinib alone or ibrutinib in combination with ublituximab. Treatment allocation was not masked to patients or investigators. Ibrutinib was given orally daily at 420 mg for all cycles. Ublituximab was given intravenously in 28-day cycles, with increasing doses during cycle 1 (≤150 mg on day 1, 750 mg on day 2, and 900 mg on days 8 and 15) and continuing at 900 mg on day 1 of cycles 2-6. After cycle 6, ublituximab was given at 900 mg every three cycles. The study was initially designed with co-primary endpoints of progression-free survival and overall response rate but due to protracted patient accrual, the protocol was amended to have a single primary endpoint of independent review committee-assessed overall response rate (defined as the proportion of patients who had a partial response, complete response, or complete response with incomplete marrow recovery according to the 2008 International Workshop on CLL criteria) in the intention-to-treat population. Safety was evaluated in the population of patients who received at least one dose of study treatment. This trial is registered with ClinicalTrials.gov, NCT02301156, and the final analysis is presented. FINDINGS: 224 patients were assessed for eligibility, of whom 126 patients were enrolled and randomly assigned to receive ublituximab plus ibrutinib (n=64) or ibrutinib alone (n=62) between Feb 6, 2015, and Dec 19, 2016. After a median follow-up of 41·6 months (IQR 36·7-47·3), the overall response rate was 53 (83%) of 64 patients in the ublituximab plus ibrutinib group and 40 (65%) of 62 patients in the ibrutinib group (p=0·020). 117 patients, including 59 in the ublituximab plus ibrutinib group and 58 in the ibrutinib group, received at least one dose of treatment and were included in safety analyses. Most adverse events were grade 1 or 2. The most common grade 3 and 4 adverse events were neutropenia (11 [19%] patients in the ublituximab plus ibrutinib group and seven [12%] in the ibrutinib group), anaemia (five [8%] and five [9%]), and diarrhoea (six [10%] and three [5%]). The most common serious adverse events were pneumonia (six [10%] in the ublituximab plus ibrutinib group and four [7%] in the ibrutinib group), atrial fibrillation (four [7%] and one [2%]), sepsis (four [7%] and one [2%]), and febrile neutropenia (three [5%] and one [2%]). Two patients in the ublituximab plus ibrutinib group died due to adverse events (one cardiac arrest and one failure to thrive), neither of which were treatment-related. Five patients in the ibrutinib group died due to adverse events, including one cardiac arrest, one cerebral infarction, one intracranial haemorrhage, one Pneumocystis jirovecii pneumonia infection, and one unexplained death; the death due to cardiac arrest was considered to be treatment-related. INTERPRETATION: The addition of ublituximab to ibrutinib resulted in a statistically higher overall response rate without affecting the safety profile of ibrutinib monotherapy in patients with relapsed or refractory high-risk chronic lymphocytic leukaemia. These findings provide support for the addition of ublituximab to Bruton tyrosine kinase inhibitors for the treatment of these patients. FUNDING: TG Therapeutics.

Safety and Patient-Reported Outcomes of Atezolizumab Plus Chemotherapy With or Without Bevacizumab Versus Bevacizumab Plus Chemotherapy in Non-Small-Cell Lung Cancer.

PURPOSE: Atezolizumab, bevacizumab, carboplatin, and paclitaxel (ABCP) demonstrated survival benefit versus bevacizumab, carboplatin, and paclitaxel (BCP) in chemotherapy-naïve nonsquamous non-small-cell lung cancer (NSCLC). We present safety and patient-reported outcomes (PROs) to provide additional information on the relative impact of adding atezolizumab to chemotherapy with and without bevacizumab in nonsquamous NSCLC. METHODS: Patients were randomly assigned to receive atezolizumab, carboplatin, and paclitaxel (ACP), ABCP, or BCP. Coprimary end points were overall survival and investigator-assessed progression-free survival. The incidence, nature, and severity of adverse events (AEs) were assessed. PROs, a secondary end point, were evaluated using the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ)-Core 30 and EORTC QLQ-Lung Cancer 13. RESULTS: Overall, 400 (ACP), 393 (ABCP), and 394 (BCP) patients were safety evaluable (ie, intention-to-treat population that received one or more doses of any study treatment). More patients had grade 3/4 treatment-related AEs during the induction versus maintenance phase (ACP, 40.5% v 8.2%; ABCP, 48.6% v 21.2%; BCP, 44.7% v 11.1%). During induction, the incidence of serious AEs (SAEs) was 28.3%, 28.5%, and 26.4% in the ACP, ABCP, and BCP arms, respectively. During maintenance, SAE incidences were 20.0%, 26.3%, and 13.0%, respectively. Completion rates of the PRO questionnaires were > 88% at baseline and remained ≥ 70% throughout most study visits. Across arms, patients on average reported no clinically meaningful worsening of global health status or physical functioning scores through cycle 13. Patients across arms rated common symptoms with chemotherapy and immunotherapy similarly. CONCLUSION: ABCP seems tolerable and manageable versus ACP and BCP in first-line nonsquamous NSCLC. Treatment tolerability differed between induction and maintenance phases across treatment arms. PROs reflect a minimal treatment burden (eg, health-related quality of life, symptoms) with each regimen.

Efficacy and Safety of Ribociclib With Letrozole in US Patients Enrolled in the MONALEESA-2 Study.

BACKGROUND: In the Mammary Oncology Assessment of LEE011's (Ribociclib's) Efficacy and Safety (MONALEESA-2) study, combination treatment with the selective inhibitor of cyclin-dependent kinases 4/6 ribociclib with letrozole significantly improved progression-free survival (PFS) versus letrozole alone in postmenopausal women with hormone receptor-positive HR+/HER2- advanced breast cancer (ABC). Herein we present results from the subset of US patients enrolled in MONALEESA-2. PATIENTS AND METHODS: Postmenopausal women with HR+/HER2- ABC without previous treatment for advanced disease were randomized (1:1) to ribociclib 600 mg/d (3 weeks on/1 week off) with letrozole 2.5 mg/d (continuous) or placebo with letrozole. The primary end point was locally assessed PFS. RESULTS: Overall, 213 US patients were enrolled in MONALEESA-2 (ribociclib, n = 100; placebo, n = 113). Baseline characteristics were similar between treatment groups and consistent with the global population. With a median follow-up of 27 months, 38 (38%) and 29 (26%) patients in the ribociclib and placebo groups, respectively, had continued to receive treatment. Median PFS was 27.6 months with ribociclib and 15.0 months with placebo (hazard ratio, 0.53). The most common all-cause adverse events were neutropenia (ribociclib, 72.0% [n = 72]; placebo, 4.6% [n = 5]), nausea (ribociclib, 69.0% [n = 69]; placebo, 44.0% [n = 48]), and fatigue (ribociclib, 60.0% [n = 60]; placebo, 50.5% [n = 55]). Two patients (ribociclib, 2.0%; placebo, 0%) experienced febrile neutropenia. CONCLUSION: In the US subset of MONALEESA-2, ribociclib with letrozole showed superior efficacy versus letrozole alone. These findings are consistent with the global population and support first-line use of ribociclib with letrozole in patients with HR+/HER2- ABC.

Docetaxel Combined With Bavituximab in Previously Treated, Advanced Nonsquamous Non-Small-Cell Lung Cancer.

BACKGROUND: Bavituximab is a phosphatidylserine-targeting antibody with a selective tumor, vascular-directed immune response. In this phase II trial the efficacy and safety of bavituximab combined with docetaxel for previously treated, advanced nonsquamous non-small-cell lung cancer were evaluated. PATIENTS AND METHODS: Patients were randomized 1:1:1 to receive docetaxel 75 mg/m(2) every 21 days for up to 6 cycles combined with weekly, blinded infusions of placebo, bavituximab 1 mg/kg, or bavituximab 3 mg/kg until disease progression or unacceptable toxicity. The primary end point was overall response rate (ORR), with a predefined end point of 26% in the bavituximab arms. After study unblinding, vial-coding discrepancies were discovered in the placebo and bavituximab 1 mg/kg groups. In exploratory analyses, data from these groups were pooled to form the control group and compared with the 3 mg/kg group. RESULTS: Efficacy end points in the bavituximab 3 mg/kg group (n = 41) and in the placebo/bavituximab 1 mg/kg group (n = 80), respectively, were as follows: ORR, 17.1% (95% confidence interval [CI], 5.6%-28.6%) and ORR, 11.3% (95% CI, 4.3%-18.2%); median progression-free survival 4.5 and 3.3 months (hazard ratio [HR], 0.74 [95% CI, 0.45-1.21]; P = .24); median overall survival 11.7 and 7.3 months (HR, 0.66 [95% CI, 0.40-1.10]; P = .11). Toxicities were manageable and similar between arms. CONCLUSION: The combination of bavituximab and docetaxel is well tolerated. Although no firm efficacy conclusions can be drawn and the trial did not meet the predefined primary end point, exploratory analyses suggest trends favoring the combination of bavituximab 3 mg/kg with docetaxel. This regimen is being evaluated in the ongoing, global, phase III SUNRISE trial.

Correlative Analysis of Genetic Alterations and Everolimus Benefit in Hormone Receptor-Positive, Human Epidermal Growth Factor Receptor 2-Negative Advanced Breast Cancer: Results From BOLERO-2.

PURPOSE: To explore the genetic landscape of tumors from patients enrolled on the BOLERO-2 trial to identify potential correlations between genetic alterations and efficacy of everolimus treatment. The BOLERO-2 trial has previously demonstrated that the addition of everolimus to exemestane prolonged progression-free survival by more than twofold in patients with hormone receptor-positive, human epidermal growth factor receptor 2-negative, advanced breast cancer previously treated with nonsteroidal aromatase inhibitors. PATIENTS AND METHODS: Next-generation sequencing was used to analyze genetic status of cancer-related genes in 302 archival tumor specimens from patients representative of the BOLERO-2 study population. Correlations between the most common somatic alterations and degree of chromosomal instability, and treatment effect of everolimus were investigated. RESULTS: Progression-free survival benefit with everolimus was maintained regardless of alteration status of PIK3CA, FGFR1, and CCND1 or the pathways of which they are components. However, quantitative differences in everolimus benefit were observed between patient subgroups defined by the exon-specific mutations in PIK3CA (exon 20 v 9) or by different degrees of chromosomal instability in the tumor tissues. CONCLUSION: The data from this exploratory analysis suggest that the efficacy of everolimus was largely independent of the most commonly altered genes or pathways in hormone receptor-positive, human epidermal growth factor receptor 2-negative breast cancer. The potential impact of chromosomal instabilities and low-frequency genetic alterations on everolimus efficacy warrants further investigation.

Purification and characterization of a cyclooxygenase-2 and angiogenesis suppressing factor produced by human fibroblasts.

Cyclooxygenase-2 (COX-2) is an inducible enzyme that plays an important role in several pathophysiological processes, including inflammation, angiogenesis, and tumorigenesis. We have recently observed that COX-2 induction is restrained in proliferating fibroblasts. The mechanism by which this occurs is unclear. Here, we report the detection and isolation from the conditioned medium of proliferating fibroblasts a factor that suppressed COX-2 expression. This factor, which was named cytoguardin, suppressed COX-2 protein levels induced by phorbol 12-myristate 13-acetate, interleukin-1beta, tumor necrosis factor alpha, and lipopolysaccharide (LPS) in fibroblasts and LPS-induced COX-2 protein levels and promoter activities in human endothelial cells and murine RAW 264.7 cells in a comparable concentration-dependent manner. It inhibited COX-2 expression induced by angiogenic factors and endothelial tube formation induced by angiogenic factors and colon cancer cell medium. These findings provide evidence for the control of COX-2 transcription by an endogenous cellular factor.

A fully human antimelanoma cellular adhesion molecule/MUC18 antibody inhibits spontaneous pulmonary metastasis of osteosarcoma cells in vivo.

PURPOSE: The melanoma cellular adhesion molecule, also known as MUC18, is highly expressed on several tumors, including bone sarcomas. The level of MUC18 expression has been found to correlate directly with tumor progression and metastatic potential. These observations have established MUC18 as a candidate mediator of tumor growth and metastasis, and suggest that blockade of MUC18 might be a potential target for immunotherapy against several MUC18-expressing tumors, including human bone sarcomas. EXPERIMENTAL DESIGN: To investigate whether blockade of MUC18 might be a potential target for immunotherapy against osteosarcoma, we have recently developed a fully human anti-MUC18 antibody, ABX-MA1. We studied the effect of ABX-MA1 on growth, adhesion, invasion, and metastasis of human osteosaroma cells both in vitro and in vivo. RESULTS: MUC18 was widely expressed on both osteosarcoma and Ewing's sarcoma cells. ABX-MA1 had no effect on the proliferation of osteosarcoma cells in vitro, nor did it significantly inhibit the growth of KRIB human osteosarcoma cells when they were orthotopically implanted into the tibias of nude mice. However, after 6 weeks, significantly fewer ABX-MA1-treated mice developed spontaneous pulmonary metastases than did IgG-treated control mice. Additionally, ABX-MA1 decreased the invasion of osteosarcoma cells through Matrigel-coated filters and disrupted homotypic adhesion between osteosarcoma cells and their heterotypic interaction with human vascular endothelial cells. CONCLUSIONS: Our findings demonstrate that MUC18 plays a central role in the metastasis of osteosarcoma and suggest that targeted inhibition of this antigen by ABX-MA1 may be a novel immunotherapeutic approach in the management of this tumor.

Randomized phase II study of carboplatin and paclitaxel with either linifanib or placebo for advanced nonsquamous non-small-cell lung cancer.

PURPOSE: Linifanib, a potent, selective inhibitor of vascular endothelial growth factor (VEGF) and platelet-derived growth factor (PDGF) receptors, has single-agent activity in non-small-cell lung cancer (NSCLC). We evaluated linifanib with carboplatin and paclitaxel as first-line therapy of advanced nonsquamous NSCLC. PATIENTS AND METHODS: Patients with stage IIIB/IV nonsquamous NSCLC were randomly assigned to 3-week cycles of carboplatin (area under the curve 6) and paclitaxel (200 mg/m(2)) with daily placebo (arm A), linifanib 7.5 mg (arm B), or linifanib 12.5 mg (arm C). The primary end point was progression-free survival (PFS); secondary efficacy end points included overall survival (OS) and objective response rate. RESULTS: One hundred thirty-eight patients were randomly assigned (median age, 61 years; 57% men; 84% smokers). Median PFS times were 5.4 months (95% CI, 4.2 to 5.7 months) in arm A (n = 47), 8.3 months (95% CI, 4.2 to 10.8 months) in arm B (n = 44), and 7.3 months (95% CI, 4.6 to 10.8 months) in arm C (n = 47). Hazard ratios (HRs) for PFS were 0.51 for arm B versus A (P = .022) and 0.64 for arm C versus A (P = .118). Median OS times were 11.3, 11.4, and 13.0 months in arms A, B, and C, respectively. HRs for OS were 1.08 for arm B versus A (P = .779) and 0.88 for arm C versus A (P = .650). Both linifanib doses were associated with increased toxicity, including a higher incidence of adverse events known to be associated with VEGF/PDGF inhibition. Baseline plasma carcinoembryonic antigen/cytokeratin 19 fragments biomarker signature was associated with PFS improvement and a trend toward OS improvement with linifanib 12.5 mg. CONCLUSION: Addition of linifanib to chemotherapy significantly improved PFS (arm B), with a modest trend for survival benefit (arm C) and increased toxicity reflective of known VEGF/PDGF inhibitory effects.

Imatinib mesylate inhibits platelet-derived growth factor receptor phosphorylation of melanoma cells but does not affect tumorigenicity in vivo.

Platelet-derived growth factor (PDGF) and its cognate receptor are widely expressed on melanomas. Coexpression of the growth factor and receptor suggests their role in autocrine or paracrine growth mechanisms. Imatinib mesylate was previously reported to have specific activity in inhibiting select tyrosine kinase receptors, including PDGF and c-Kit. Melanoma cells express abundant levels of the PDGF receptor (PDGFR). Nevertheless, c-Kit expression is progressively lost as the cells take on a more highly metastatic phenotype. To investigate the potential of imatinib mesylate as a therapy for melanoma, we studied its effect on the growth of melanoma cells using an in vivo mouse model. Melanoma cells with high malignant potential (PDGFR-positive, c-Kit-negative) or low malignant potential (PDGFR-positive, c-Kit-positive) were injected subcutaneously into athymic nude mice. Mice were treated with imatinib mesylate (100 mg/kg three times weekly) or with phosphate-buffered saline for 4 to 6 wk. PDGFR-alpha and -beta were expressed on all melanoma cell lines tested. The level of PDGFR expression correlated with the metastatic potential of the melanoma cells: higher levels of PDGFR-alpha were expressed on cells with higher metastatic potential, and higher levels of PDGFR-beta were expressed on cells with lower metastatic potential. There was no significant difference in tumor size between treated and control mice. Immunohistochemical studies demonstrated inhibition of PDGFR phosphorylation on the tumors from mice treated with imatinib mesylate but not from control mice, suggesting that the receptors were functional and that the concentration of drug used was appropriate. Our data demonstrated that imatinib mesylate blocked both PDGFR-alpha and PDGFR-beta in vivo. It did not, however, affect the growth of melanoma cells expressing PDGFR, regardless of whether the cells expressed c-Kit.

Everolimus in hormone receptor-positive advanced breast cancer: targeting receptor-based mechanisms of resistance.

Although patients with hormone receptor (HR)-positive breast cancer are successfully treated with endocrine therapy, many tumors go on to develop resistance to these agents. Studies have determined that mechanisms of resistance to endocrine therapy are quite complex and can involve a multitude of signal transduction pathways, either through direct association with the estrogen receptor or through cross-talk with other pathways. Preclinical studies have suggested the therapeutic importance of the mammalian target of rapamycin (mTOR) pathway and that inhibiting this pathway may restore sensitivity to endocrine therapy. The oral mTOR inhibitor everolimus has been extensively studied for breast cancer. Clinical studies suggest that everolimus in combination with endocrine therapy improves progression-free survival and is well tolerated. A combined approach, targeting both mTOR signal transduction and the HR pathways, promises to take clinical research in a new direction for the treatment of HR-positive advanced breast cancer.

Effect of visceral metastases on the efficacy and safety of everolimus in postmenopausal women with advanced breast cancer: subgroup analysis from the BOLERO-2 study.

BACKGROUND: Everolimus (EVE; an inhibitor of mammalian target of rapamycin [mTOR]) enhances treatment options for postmenopausal women with hormone-receptor-positive (HR(+)), human epidermal growth factor receptor-2-negative (HER2(-)) advanced breast cancer (ABC) who progress on a non-steroidal aromatase inhibitor (NSAI). This is especially true for patients with visceral disease, which is associated with poor prognosis. The BOLERO-2 (Breast cancer trial of OraLEveROlimus-2) trial showed that combination treatment with EVE and exemestane (EXE) versus placebo (PBO)+EXE prolonged progression-free survival (PFS) by both investigator (7.8 versus 3.2 months, respectively) and independent (11.0 versus 4.1 months, respectively) central assessment in postmenopausal women with HR(+), HER2(-) ABC recurring/progressing during/after NSAI therapy. The BOLERO-2 trial included a substantial proportion of patients with visceral metastases (56%). METHODS: Prespecified exploratory subgroup analysis conducted to evaluate the efficacy and safety of EVE+EXE versus PBO+EXE in a prospectively defined subgroup of patients with visceral metastases. FINDINGS: At a median follow-up of 18 months, EVE+EXE significantly prolonged median PFS compared with PBO+EXE both in patients with visceral metastases (N=406; 6.8 versus 2.8 months) and in those without visceral metastases (N=318; 9.9 versus 4.2 months). Improvements in PFS with EVE+EXE versus PBO+EXE were also observed in patients with visceral metastases regardless of Eastern Cooperative Oncology Group performance status (ECOG PS). Patients with visceral metastases and ECOG PS 0 had a median PFS of 6.8 months with EVE+EXE versus 2.8 months with PBO+EXE. Among patients with visceral metastases and ECOG PS ≥1, EVE+EXE treatment more than tripled median PFS compared with PBO+EXE (6.8 versus 1.5 months). INTERPRETATION: Adding EVE to EXE markedly extended PFS by ≥4 months among patients with HR(+) HER2(-) ABC regardless of the presence of visceral metastases.

Inhibition of p90 ribosomal S6 kinase-mediated CCAAT/enhancer-binding protein beta activation and cyclooxygenase-2 expression by salicylate.

We have previously shown that salicylate at a pharmacological concentration suppresses CCAAT/enhancer-binding protein beta (C/EBPbeta) binding, thereby reducing cyclooxygenase-2 (COX-2) and inducible nitric-oxide synthase expression (Saunders, M. A., Sansores-Garcia, L., Gilroy, D. W., and Wu, K. K. (2001) J. Biol. Chem. 276, 18897-18904; Cieslik, K., Zhu, Y., and Wu, K. K. (2002) J. Biol. Chem. 277, 49304-49310). We postulated that salicylate targets a kinase that phosphorylates and activates C/EBPbeta. Here we report the identification of p90 ribosomal S6 kinase (RSK) as a target of salicylate. Salicylate inhibited RSK in vivo and blocked the activity of RSK2 purified from cells stimulated by phorbol 12-myristate 13-acetate (PMA). Mutation of the RSK-phosphorylation site (T266A) of C/EBPbeta abrogated PMA-stimulated C/EBPbeta binding activity. RSK activation was required for PMA-induced COX-2 transcriptional activation. Salicylate also inhibited Ras and extracellular signal-regulated kinase (ERK) activation induced by PMA. We conclude that salicylate inhibits C/EBPbeta-mediated COX-2 transcriptional activation by blocking RSK activity and Ras signaling pathway.