Salvador Martín-Algarra

Dabrafenib in BRAF-mutated metastatic melanoma: A multicentre, open-label, phase 3 randomised controlled trial

BACKGROUND Dabrafenib, an inhibitor of mutated BRAF, has clinical activity with a manageable safety profile in studies of phase 1 and 2 in patients with BRAF(V600)-mutated metastatic melanoma. We studied the efficacy of dabrafenib in patients with BRAF(V600E)-mutated metastatic melanoma. METHODS We enrolled patients in this open-label phase 3 trial between Dec 23, 2010, and Sept 1, 2011. This report is based on a data cutoff date of Dec 19, 2011. Patients aged 18 years or older with previously untreated, stage IV or unresectable stage III BRAF(V600E) mutation-positive melanoma were randomly assigned (3:1) to receive dabrafenib (150 mg twice daily, orally) or dacarbazine (1000 mg/m(2) intravenously every 3 weeks). Patients were stratified according to American Joint Committee on Cancer stage (unresectable III+IVM1a+IVM1b vs IVM1c). The primary endpoint was investigator-assessed progression-free survival and was analysed by intention to treat; safety was assessed per protocol. This study is registered with ClinicalTrials.gov, number NCT01227889. FINDINGS Of the 733 patients screened, 250 were randomly assigned to receive either dabrafenib (187 patients) or dacarbazine (63 patients). Median progression-free survival was 5·1 months for dabrafenib and 2·7 months for dacarbazine, with a hazard ratio (HR) of 0·30 (95% CI 0·18-0·51; p<0·0001). At data cutoff, 107 (57%) patients in the dabrafenib group and 14 (22%) in the dacarbazine group remained on randomised treatment. Treatment-related adverse events (grade 2 or higher) occurred in 100 (53%) of the 187 patients who received dabrafenib and in 26 (44%) of the 59 patients who received dacarbazine. The most common adverse events with dabrafenib were skin-related toxic effects, fever, fatigue, arthralgia, and headache. The most common adverse events with dacarbazine were nausea, vomiting, neutropenia, fatigue, and asthenia. Grade 3-4 adverse events were uncommon in both groups. INTERPRETATION Dabrafenib significantly improved progression-free survival compared with dacarbazine. FUNDING GlaxoSmithKline.

Front-Line Paclitaxel/Cisplatin-Based Chemotherapy in Brain Metastases from Non-Small-Cell Lung Cancer

Objective: Paclitaxel-cisplatin is considered to be a standard therapy for metastatic non-small-cell lung cancer (NSCLC). The aim of this study was to evaluate the activity and toxicity of this combination with vinorelbine or gemcitabine as front-line therapy in brain metastases from NSCLC. Methods: Twenty-six chemotherapy-naive patients with an ECOG performance status of 0–2 were treated with paclitaxel (135 mg/m2) on day 1, cisplatin (120 mg/m2) on day 1, and either vinorelbine (30 mg/m2) on days 1 and 15 or gemcitabine (800 mg/m2) on days 1 and 8. Whole-brain irradiation was offered early in case of progression and later as consolidation treatment. Results: All patients were evaluated for toxicity and 25 for response. An intracranial response rate was observed in 38% of the patients (95% CI: 22–59%). WHO grade 3–4 neutropenia and thrombocytopenia occurred in 31 and 4% of the patients, respectively. There was one treatment-related death. Non-hematological toxicities were mild. After a median follow-up of 46 months, the median overall survival for all patients was 21.4 weeks and the median time to progression was 12.8 weeks. Conclusions: Paclitaxel and cisplatin combined with vinorelbine or gemcitabine as front-line therapy in brain metastases seem to achieve responses similar to those for extracranial disease, suggesting a meaningful role in this setting.

Quantitative Cell-Free Circulating BRAFV600E Mutation Analysis by Use of Droplet Digital PCR in the Follow-up of Patients with Melanoma Being Treated with BRAF Inhibitors

BACKGROUND Around 50% of cutaneous melanomas harbor the BRAF(V600E) mutation and can be treated with BRAF inhibitors. DNA carrying this mutation can be released into circulation as cell-free BRAF(V600E) (cfBRAF(V600E)). Droplet digital PCR (ddPCR) is an analytically sensitive technique for quantifying small concentrations of DNA. We studied the plasma concentrations of cfBRAF(V600E) by ddPCR in patients with melanoma during therapy with BRAF inhibitors. METHODS Plasma concentrations of cfBRAF(V600E) were measured in 8 controls and 20 patients with advanced melanoma having the BRAF(V600E) mutation during treatment with BRAF inhibitors at baseline, first month, best response, and progression. RESULTS The BRAF(V600E) mutation was detected by ddPCR even at a fractional abundance of 0.005% in the wild-type gene. Agreement between tumor tissue BRAF(V600E) and plasma cfBRAF(V600E) was 84.3%. Baseline cfBRAF(V600E) correlated with tumor burden (r = 0.742, P < 0.001). cfBRAF(V600E) concentrations decreased significantly at the first month of therapy (basal median, 216 copies/mL; Q1-Q3, 27-647 copies/mL; first response median, 0 copies/mL; Q1-Q3, 0-49 copies/mL; P < 0.01) and at the moment of best response (median, 0 copies/mL; Q1-Q3, 0-33 copies/mL; P < 0.01). At progression, there was a significant increase in the concentration of cfBRAF(V600E) compared with best response (median, 115 copies/mL; Q1-Q3, 3-707 copies/mL; P = 0.013). Lower concentrations of basal cfBRAF(V600E) were significantly associated with longer overall survival and progression-free survival (27.7 months and 9 months, respectively) than higher basal concentrations (8.6 months and 3 months, P < 0.001 and P = 0.024, respectively). CONCLUSIONS cfBRAF(V600E) quantification in plasma by ddPCR is useful as a follow-up to treatment response in patients with advanced melanoma.

Imatinib Inhibits Proliferation of Ewing Tumor Cells Mediated by the Stem Cell Factor/KIT Receptor Pathway, and Sensitizes Cells to Vincristine and Doxorubicin-Induced Apoptosis

Purpose and Experimental Design: The stem cell factor/KIT receptor loop may represent a novel target for molecular-based therapies of Ewing tumor. We analyzed the in vitro impact of KIT blockade by imatinib in Ewing tumor cell lines. Results: KIT expression was detected in 4 of 4 Ewing tumor cell lines and in 49 of 110 patient samples (44.5%) by immunohistochemistry and/or Western blot analysis. KIT expression was stronger in Ewing tumors showing EWS-FLI1 nontype 1 fusions. Despite absence of c-kit mutations, constitutive and ligand-inducible phosphorylation of KIT was found in all tumor cell lines, indicating an active receptor. Treatment with KIT tyrosine kinase inhibitor imatinib (0.5–20 μm) induced down-regulation of KIT phosphorylation and dose response inhibition of cell proliferation (IC50, 12–15 μm). However, imatinib administered alone at doses close to IC50 for growth inhibition (10 μm) did not induce a significant increase in apoptosis. We then analyzed if blockade of KIT loop through imatinib (10 μm) was able to increase the antitumor in vitro effect of doxorubicin (DXR) and vincristine (VCR), drugs usually used in Ewing tumor treatment. Addition of imatinib decreased in 15–20 and 15–36% of the proliferative rate of Ewing tumor cells exposed to DXR and VCR, respectively, and increased in 15 and 30% of the apoptotic rate of Ewing tumor cells exposed to the same drugs. Conclusions: Inhibition of Ewing tumor cell proliferation by imatinib is mediated through blockade of KIT receptor signaling. Inhibition of KIT increases sensitivity of these cells to DXR and VCR. This study supports a potential role for imatinib in the treatment of Ewing tumor.

Serum Interleukin-8 Reflects Tumor Burden and Treatment Response across Malignancies of Multiple Tissue Origins

Purpose: Interleukin-8 (IL8) is a chemokine produced by malignant cells of multiple cancer types. It exerts various functions in shaping protumoral vascularization and inflammation/immunity. We evaluated sequential levels of serum IL8 in preclinical tumor models and in patients to assess its ability to estimate tumor burden. Experimental Design: IL8 levels were monitored by sandwich ELISAs in cultured tumor cells supernatants, tumor-xenografted mice serum, and in samples from 126 patients with cancer. We correlated IL8 serum levels with baseline tumor burden and with treatment-induced changes in tumor burden, as well as with prognosis. Results: IL8 concentrations correlated with the number of IL8-producing tumor cells in culture. In xenografted neoplasms, IL8 serum levels rapidly dropped after surgical excision, indicating an accurate correlation with tumor burden. In patients with melanoma (n = 16), renal cell carcinoma (RCC; n = 23), non–small cell lung cancer (NSCLC; n = 21), or hepatocellular carcinoma (HCC; n = 30), serum IL8 concentrations correlated with tumor burden and stage, survival (melanoma, n = 16; RCC, n = 23; HCC, n = 33), and objective responses to therapy, including those to BRAF inhibitors (melanoma, n = 16) and immunomodulatory monoclonal antibodies (melanoma, n = 8). IL8 concentrations in urine (n = 18) were mainly elevated in tumors with direct contact with the urinary tract. Conclusions: IL8 levels correlate with tumor burden in preclinical models and in patients with cancer. IL8 is a potentially useful biomarker to monitor changes in tumor burden following anticancer therapy, and has prognostic significance. Clin Cancer Res; 20(22); 5697–707. ©2014 AACR.

Assessment of Epidermal Growth Factor Receptor and K-Ras Mutation Status in Cytological Stained Smears of Non-Small Cell Lung Cancer Patients: Correlation with Clinical Outcomes

OBJECTIVE Epidermal growth factor receptor (EGFR) and K-ras mutations guide treatment selection in non-small cell lung cancer (NSCLC) patients. Although mutation status is routinely assessed in biopsies, cytological specimens are frequently the only samples available. We determined EGFR and K-ras mutations in cytological samples. METHODS DNA was extracted from 150 consecutive samples, including 120 Papanicolau smears (80%), 10 cell blocks (7%), nine fresh samples (6%), six ThinPrep® tests (4%), and five body cavity fluids (3.3%). Papanicolau smears were analyzed when they had >50% malignant cells. Polymerase chain reaction and direct sequencing of exons 18-21 of EGFR and exon 2 of K-ras were performed. EGFR mutations were simultaneously determined in biopsies and cytological samples from 20 patients. Activity of EGFR tyrosine kinase inhibitors (TKIs) was assessed. RESULTS The cytological diagnosis was adenocarcinoma in 110 samples (73%) and nonadenocarcinoma in 40 (27%) samples. EGFR mutations were identified in 26 samples (17%) and K-ras mutations were identified in 18 (12%) samples. EGFR and K-ras mutations were mutually exclusive. In EGFR-mutated cases, DNA was obtained from stained smears in 24 cases (92%), pleural fluid in one case (4%), and cell block in one case (4%). The response rate to EGFR TKIs in patients harboring mutations was 75%. The mutation status was identical in patients who had both biopsies and cytological samples analyzed. CONCLUSION Assessment of EGFR and K-ras mutations in cytological samples is feasible and comparable with biopsy results, making individualized treatment selection possible for NSCLC patients from whom tumor biopsies are not available.

Study of Circulating MicroRNA-125b Levels in Serum Exosomes in Advanced Melanoma

CONTEXT Malignant melanoma is an aggressive tumor that produces exosomes, which contain microRNAs (miRNAs) that could be of utility in following tumoral cell dysregulation. MicroR-125b is a miRNA whose down-regulation seems to be implicated in melanoma progression. OBJECTIVE To analyze miR-125b levels in serum, and in exosomes obtained from serum, from patients with advanced melanoma. DESIGN Serum samples were obtained from 21 patients with advanced melanoma, from 16 disease-free patients with melanoma, and from 19 healthy volunteers. Exosomes were isolated from serum by precipitation, and miR-16 and miR-125b levels were quantified by real-time polymerase chain reaction. RESULTS MicroR-16, but not miR-125b, was detected in all samples, and miR-16 levels were significantly higher in serum than they were in exosomes. MicroR-16 expression levels did not differ significantly between the 2 groups (patients with melanoma and healthy donors). There was a significant relationship between miR-125b and miR-16 levels in exosomes. Additionally, miR-125b levels in exosomes were significantly lower in patients with melanoma compared with disease-free patients with melanoma and healthy controls. CONCLUSIONS Exosomes can provide a suitable material to measure circulating miRNA in melanoma, and miR-16 can be used as an endogenous normalizer. Lower levels of miR-125b in exosomes obtained from serum are associated with advanced melanoma disease, probably reflecting the tumoral cell dysregulation.

Preliminary Results of the Combination of Bevacizumab and Weekly Paclitaxel in Advanced Melanoma

Background: Pretreated advanced melanoma is a poor prognosis scenario with few, if any, active therapeutic options. The antibody against vascular endothelial growth factor, bevacizumab, has demonstrated increased activity in combination with chemotherapy in many tumors. We intended to evaluate the activity of the combination of weekly paclitaxel and bevacizumab in previously treated metastatic melanoma. Patients and Methods: Patients with previously treated metastatic melanoma received paclitaxel 70 mg/m2 weekly and bevacizumab 10 mg/kg biweekly for 5 consecutive weeks every 6 weeks. Results: Twelve patients were treated. Two patients (16.6%) achieved a partial response and 7 patients (58.3%) stable disease. Responses were seen in soft tissue, lung and brain metastases. Median disease-free and overall survival times were 3.7 and 7.8 months, respectively. Treatment was well tolerated. Main toxicities were grade 3 asymptomatic lymphopenia in 6 patients, grade 3 leucopenia in 2 patients, and grade 3 thrombocytopenia in 1 patient. Conclusions: Our preliminary results suggest that the combination of bevacizumab and weekly paclitaxel is active and safe in patients with metastatic melanoma, warranting further investigation.

Phase II study of weekly Kahalalide F in patients with advanced malignant melanoma

This phase II clinical trial evaluated the antitumour response of Kahalalide F (KF) 650 microg/m(2) given as a 1-h weekly infusion in advanced malignant melanoma patients, both untreated and those who relapsed or progressed after one line of systemic therapy. Of 24 enrolled patients (median age, 55 years; range, 28-89), 14 patients had been previously treated with chemotherapy or biological therapy. No RECIST responses occurred; five chemotherapy-naïve patients with cutaneous melanoma had disease stabilisation for > or = 3 months; median progression-free survival was 1.7 months (95% CI, 1.2-1.9 months); and median overall survival was 10.8 months (95% CI, 5.0-upper limit not reached). The most common laboratory toxicities were non-cumulative increase of transaminases (ALT/AST) and gamma-glutamyltransferase (GGT). No patients experienced leukopenia and thrombocytopenia during the study. KF was a well-tolerated and safe chemotherapy regimen. Despite a favourable safety profile, this trial was closed after the first stage because of the lack of objective response in patients with malignant melanoma.

Pilot Clinical Trial of Type 1 Dendritic Cells Loaded with Autologous Tumor Lysates Combined with GM-CSF, Pegylated IFN, and Cyclophosphamide for Metastatic Cancer Patients

Twenty-four patients with metastatic cancer received two cycles of four daily immunizations with monocyte-derived dendritic cells (DC). DC were incubated with preheated autologous tumor lysate and subsequently with IFN-α, TNF-α, and polyinosinic:polycytidylic acid to attain type 1 maturation. One DC dose was delivered intranodally, under ultrasound control, and the rest intradermally in the opposite thigh. Cyclophosphamide (day −7), GM-CSF (days 1–4), and pegIFN alpha-2a (days 1 and 8) completed each treatment cycle. Pretreatment with cyclophosphamide decreased regulatory T cells to levels observed in healthy subjects both in terms of percentage and in absolute counts in peripheral blood. Treatment induced sustained elevations of IL-12 in serum that correlated with the output of IL-12p70 from cultured DC from each individual. NK activity in peripheral blood was increased and also correlated with the serum concentration of IL-12p70 in each patient. Circulating endothelial cells decreased in 17 of 18 patients, and circulating tumor cells markedly dropped in 6 of 19 cases. IFN-γ–ELISPOT responses to DC plus tumor lysate were observed in 4 of 11 evaluated cases. Tracing DC migration with [111In] scintigraphy showed that intranodal injections reached deeper lymphatic chains in 61% of patients, whereas with intradermal injections a small fraction of injected DC was almost constantly shown to reach draining inguinal lymph nodes. Five patients experienced disease stabilization, but no objective responses were documented. This combinatorial immunotherapy strategy is safe and feasible, and its immunobiological effects suggest potential activity in patients with minimal residual disease. A randomized trial exploring this hypothesis is currently ongoing.