Juan Carlos Tercero

Fast track — ArticlesEfficacy of trabectedin (ecteinascidin-743) in advanced pretreated myxoid liposarcomas: a retrospective study

BACKGROUND Previous studies have suggested that trabectedin (ecteinascidin-743) could have antitumour activity in soft-tissue sarcoma. We aimed to study the usefulness of trabectedin in the treatment of patients with myxoid liposarcomas, a subtype of liposarcoma that is associated with specific chromosomal translocations t(12;16)(q13;p11) or t(12;22)(q13;q12) that result in the formation of DDIT3-FUS or DDIT3-EWSR1 fusion proteins. METHODS 51 patients with advanced pretreated myxoid liposarcoma who started treatment with trabectedin between April 4, 2001, and Sept 18, 2006 at five institutions in a compassionate-use programme were analysed retrospectively. Centralised radiological and pathological reviews were done for most patients. Trabectedin was given either as a 24-h continuous infusion or as a 3-h infusion, every 21 days, at 1.1-1.5 mg(2). 558 courses of trabectedin were given in total, with a median of ten courses for each patient (range 1-23). The primary endpoints were response rate and progression-free survival, and the secondary endpoint was overall survival. FINDINGS According to Response Evaluation Criteria in Solid Tumors (RECIST), after a median follow-up of 14.0 months (IQR 8.7-20.0), two patients had complete responses (CR) and 24 patients had partial responses (PR); the overall response was 51% (95% CI 36-65). Five patients had early progressive disease. In 17 of the 23 patients who achieved PR or CR as defined by RECIST and who had centralised radiological review, tissue-density changes, consisting of a decrease in tumour density on CT scan or a decrease in contrast enhancement on MRI (or both), preceded tumour shrinkage. Median progression-free survival was 14.0 months (13.1-21.0), and progression-free survival at 6 months was 88% (79-95). INTERPRETATION Trabectedin was associated with antitumour activity in this series of patients with myxoid liposarcoma. The noted patterns of tumour response were such that tissue density changes occurred before tumour shrinkage in several patients. In some patients, tissue-density changes only were seen. Long-lasting tumour control was noted in responsive patients. The compassionate-use programme is still ongoing. This analysis has resulted in the initiation of two prospective studies to assess the role of trabectedin in the treatment of patients with myxoid liposarcoma in preoperative and metastatic settings. Furthermore, the selective mechanism of action for trabectedin in this translocation-related sarcoma is being studied.

Antitumor and anti-inflammatory effects of trabectedin on human myxoid liposarcoma cells.

Inflammatory mediators present in the tumor milieu may promote cancer progression and are considered promising targets of novel biological therapies. We previously reported that the marine antitumor agent trabectedin, approved in Europe in 2007 for soft tissue sarcomas and in 2009 for ovarian cancer, was able to downmodulate the production of selected cytokines/chemokines in immune cells. Patients with myxoid liposarcoma (MLS), a subtype characterized by the expression of the oncogenic transcript FUS-CHOP, are highly responsive to trabectedin. The drug had marked antiproliferative effects on MLS cell lines at low nanomolar concentrations. We tested the hypothesis that trabectedin could also affect the inflammatory mediators produced by cancer cells. Here, we show that MLS express several cytokines, chemokines, and growth factors (CCL2, CCL3, CCL5, CXCL8, CXCL12, MIF, VEGF, SPARC) and the inflammatory and matrix-binder protein pentraxin 3 (PTX3), which build up a prominent inflammatory environment. In vitro treatment with noncytotoxic concentrations of trabectedin selectively inhibited the production of CCL2, CXCL8, IL-6, VEGF, and PTX3 by MLS primary tumor cultures and/or cell lines. A xenograft mouse model of human MLS showed marked reduction of CCL2, CXCL8, CD68+ infiltrating macrophages, CD31+ tumor vessels, and partial decrease of PTX3 after trabectedin treatment. Similar findings were observed in a patient tumor sample excised after several cycles of therapy, indicating that the results observed in vitro might have in vivo relevance. In conclusion, trabectedin has dual effects in liposarcoma: in addition to direct growth inhibition, it affects the tumor microenvironment by reducing the production of key inflammatory mediators.

Phase II clinical trial of neoadjuvant trabectedin in patients with advanced localized myxoid liposarcoma

BACKGROUND To evaluate neoadjuvant trabectedin (1.5 mg/m2 24-h i.v. infusion every 3 weeks; three to six cycles) in patients with locally advanced myoxid liposarcoma (ML) previously untreated with chemotherapy or radiation. PATIENTS AND METHODS Primary efficacy end point was pathological complete response (pCR) or tumoral regression rate. Objective response according to RECIST (v.1.0) was a secondary end point. RESULTS Three of 23 assessable patients had pCR [13%; 95% confidence interval (CI), 3% to 34%]. Furthermore, very good and moderate histological responses were observed in another 2 and 10 patients, respectively. Histological decrement in the cellular and vascular tumor component and maturation of tumor cells to lipoblasts were observed in both myoxid and myoxid/round cell variants. Seven patients had partial response according to RECIST (objective response rate of 24%; 95% CI, 10% to 44%). No disease progression was reported. Neoadjuvant trabectedin was usually well tolerated, with a safety profile similar to that described in patients with soft tissue sarcoma or other tumor types. CONCLUSION Trabectedin 1.5 mg/m2 given as a 24-h i.v. infusion every 3 weeks is a therapeutic option in the neoadjuvant setting of ML.BACKGROUND To evaluate neoadjuvant trabectedin (1.5 mg/m(2) 24-h i.v. infusion every 3 weeks; three to six cycles) in patients with locally advanced myoxid liposarcoma (ML) previously untreated with chemotherapy or radiation. PATIENTS AND METHODS Primary efficacy end point was pathological complete response (pCR) or tumoral regression rate. Objective response according to RECIST (v.1.0) was a secondary end point. RESULTS Three of 23 assessable patients had pCR [13%; 95% confidence interval (CI), 3% to 34%]. Furthermore, very good and moderate histological responses were observed in another 2 and 10 patients, respectively. Histological decrement in the cellular and vascular tumor component and maturation of tumor cells to lipoblasts were observed in both myoxid and myoxid/round cell variants. Seven patients had partial response according to RECIST (objective response rate of 24%; 95% CI, 10% to 44%). No disease progression was reported. Neoadjuvant trabectedin was usually well tolerated, with a safety profile similar to that described in patients with soft tissue sarcoma or other tumor types. CONCLUSION Trabectedin 1.5 mg/m(2) given as a 24-h i.v. infusion every 3 weeks is a therapeutic option in the neoadjuvant setting of ML.

Predictive impact of DNA repair functionality on clinical outcome of advanced sarcoma patients treated with trabectedin: a retrospective multicentric study.

AIM Trabectedin sensitivity is increased in cells with functional nucleotide excision DNA repair, whereas efficient homologous recombination repair leads to resistance. On this basis, a retrospective study of mRNA expression of BRCA1 (breast cancer susceptibility 1 gene), XPG (Xeroderma pigmentosum group G gene) and ERCC1 (excision-repair cross complementing group 1 gene) in tumour samples from sarcoma patients treated with trabectedin was conducted, to correlate DNA repair profiles with patient outcome. MATERIALS AND METHODS Quantification of expression in paraffin embedded tumour samples from 245 patients with advanced sarcomas was performed by qRT-PCR (quantitative real-time polymerase chain reaction). Median values were used as cut-off to define low/high mRNA expression. RESULTS Low BRCA1 mRNA expression in tumour samples correlated with statistically significant better response to trabectedin. In contrast to other DNA interacting agents, high expression of XPG was significantly correlated with increased response to the drug and high ERCC1 or XPD (Xeroderma pigmentosum group D gene) expression did not have a detrimental impact. A composite signature including low BRCA1 and high ERCC1 and/or XPG identifies a highly sensitive population of sarcomas with significantly improved treatment outcome. DISCUSSION This retrospective study indicates that the DNA repair profile predicts improved outcomes in advanced sarcoma patients when treated with trabectedin. This clinical utility of this signature should be evaluated in prospective enriching studies in sarcoma and other malignancies for patients sensitive to trabectedin.

Transcriptional signature of Ecteinascidin 743 (Yondelis, Trabectedin) in human sarcoma cells explanted from chemo-naïve patients

Ecteinascidin 743 (ET-743; Yondelis, Trabectedin) is a marine anticancer agent that induces long-lasting objective remissions and tumor control in a subset of patients with pretreated/resistant soft-tissue sarcoma. Drug-induced tumor control is achievable in 22% of such patients, but there is no clear indication of the molecular features correlated with clinical sensitivity/resistance to ET-743. Nine low-passage, soft-tissue sarcoma cell lines, explanted from chemo-naïve patients with different patterns of sensitivity, have been profiled with a cDNA microarray containing 6,700 cancer-related genes. The molecular signature of these cell lines was analyzed at baseline and at four different times after ET-743 exposure. The association of levels of TP53 mutation and TP73 expression with ET-743 sensitivity and cell cycle kinetics after treatment was also analyzed. Gene expression profile analysis revealed up-regulation of 86 genes and down-regulation of 244 genes in response to ET-743. The ET-743 gene expression signature identified a group of genes related with cell cycle control, stress, and DNA-damage response (JUNB, ATF3, CS-1, SAT, GADD45B, and ID2) that were up-regulated in all the cell lines studied. The transcriptional signature 72 hours after ET-743 administration, associated with ET-743 sensitivity, showed a more efficient induction of genes involved in DNA-damage response and apoptosis, such as RAD17, BRCA1, PAR4, CDKN1A, and P53DINP1, in the sensitive cell line group. The transcriptional signature described here may lead to the identification of ET-743 downstream mediators and transcription regulators and the proposal of strategies by which ET-743–sensitive tumors may be identified.

ERCC5/XPG, ERCC1, and BRCA1 gene status and clinical benefit of trabectedin in patients with soft tissue sarcoma

The objective of this study was to determine whether specific single nucleotide polymorphisms (SNPs) from nucleotide excision repair (NER) and homologous recombination (HR) DNA repair pathways are associated with sensitivity to trabectedin in patients with soft tissue sarcoma (STS).

Relevance of the Fanconi anemia pathway in the response of human cells to trabectedin.

Trabectedin (Yondelis; ET-743) is a potent anticancer drug that binds to DNA by forming a covalent bond with a guanine in one strand and one or more hydrogen bonds with the opposite strand. Using a fluorescence-based melting assay, we show that one single trabectedin-DNA adduct increases the thermal stability of the double helix by >20°C. As deduced from the analysis of phosphorylated H2AX and Rad51 foci, we observed that clinically relevant doses of trabectedin induce the formation of DNA double-strand breaks in human cells and activate homologous recombination repair in a manner similar to that evoked by the DNA interstrand cross-linking agent mitomycin C (MMC). Because one important characteristic of this drug is its marked cytotoxicity on cells lacking a functional Fanconi anemia (FA) pathway, we compared the response of different subtypes of FA cells to MMC and trabectedin. Our data clearly show that human cells with mutations in FANCA, FANCC, FANCF, FANCG, or FANCD1 genes are highly sensitive to both MMC and trabectedin. However, in marked contrast to MMC, trabectedin does not induce any significant accumulation of FA cells in G2-M. The critical relevance of FA proteins in the response of human cells to trabectedin reported herein, together with observations showing the role of the FA pathway in cancer suppression, strongly suggest that screening for mutations in FA genes may facilitate the identification of tumors displaying enhanced sensitivity to this novel anticancer drug. [Mol Cancer Ther 2008;7(5):1309–18]

Levels of p27(kip1) determine Aplidin sensitivity.

Aplidin (plitidepsin) is a novel anticancer drug isolated from the marine tunicate Aplidium albicans. Aplidin shows potent antitumor activity in preclinical models against a wide variety of human tumors. Aplidin is currently in phase II clinical trials in a variety of solid tumors and hematologic malignancies. Moreover, clinical studies of Aplidin in combination with other agents are ongoing because it generally lacks cross-resistance with other known cytotoxic drugs. The mode of action of Aplidin in tumor cells is only partially understood. Aplidin induces an early oxidative stress response, which results in a rapid and sustained activation of the epidermal growth factor receptor, the nonreceptor protein tyrosine kinase Src, and the serine threonine kinases c-Jun NH2-terminal kinase and p38 mitogen-activated protein kinase. Here, we show that sensitivity to Aplidin correlates inversely with the levels of expression of the cyclin-dependent kinase inhibitor p27kip1 (p27) in a panel of low passaged human sarcoma cell lines. Aplidin induces p27 through an oxidation-dependent mechanism and the reduction of p27 levels by specific short hairpin RNA increases Aplidin sensitivity. We confirmed these results in p27 null mouse embryonic fibroblasts corroborating the specificity of the p27 role in Aplidin response because p21waf1 null mouse embryonic fibroblasts do not show this increased sensitivity. We propose a mechanism of action of Aplidin involving p27 and support the analysis of p27 in the response to Aplidin in currently ongoing clinical trials to establish the levels of this protein as response predictor. [Mol Cancer Ther 2007;6(4):1310–6]

Extreme sensitivity to Yondelis® (Trabectedin, ET‐743) in low passaged sarcoma cell lines correlates with mutated p53

Yondelis® (Trabectedin, ET‐743) is a marine anticancer agent currently in Phase II/III development in patients with advanced pretreated soft tissue sarcoma. In the present study, we generated a panel of low passaged tumor cell lines from samples explanted from chemonaive sarcoma patients with different tumor types. We assessed in vitro sensitivity/resistance to Trabectedin and doxorubicin in a panel of sarcoma cell lines and examined the correlation between molecular alterations in DNA repair genes and sensitivity to Trabectedin. We treated cell lines with Trabectedin and doxorubicin in both 96‐h and clonogenic assays. In both assays, well‐defined groups of resistant and sensitive cell lines were observed. Resistance to Trabectedin did not correlate with resistance to doxorubicin, indicating that the two drugs may have different mechanisms of resistance. p53 mutations and deletions correlated with extreme sensitivity (IC50 < 1 nM) to Trabectedin (P < 0.01). In a pair of isogenic cell lines differing only in the presence or absence of wild‐type p53, the absence of p53 rendered cells threefold more sensitive to Trabectedin. J. Cell. Biochem. 100: 339–348, 2007.

Novel Models of Myxoid Liposarcoma Xenografts Mimicking the Biological and Pharmacologic Features of Human Tumors

Purpose: Myxoid liposarcoma is a common subtype of liposarcoma. It is associated in more than 90% of cases with the chromosomal translocation t(12;16)(q13;p11) leading to the fusion FUS-CHOP gene that is responsible for the oncogenic transformation of preadipocytes. Recently the marine natural product trabectedin has shown highly selective activity for myxoid liposarcoma, even in the most aggressive round-cell subtype. Experimental Design: Fragments of 17 sarcomas were transplanted s.c. in female athymic NCr-nu/nu mice. Xenografts were established and characterized by morphology, fluorescence in situ hybridization analysis for the translocation and reverse transcriptase-PCR analysis for fusion transcripts. Trabectedin was injected i.v. Results: Seven of 17 tumors grew as continuous xenografts, five of them being myxoid liposarcoma of the round-cell subtype. The chromosomal rearrangement and fusion transcripts in different passages were the same as in the human tumors from which they were derived. The responsiveness to trabectedin in type II myxoid liposarcoma xenografts was as high as in patients. The pathologic response was associated with the presence of the FUS-CHOP fusion gene, indicating that the drug does not totally eradicate the disease. Type III myxoid liposarcoma xenografts seemed much less sensitive to trabectedin, confirming previous clinical observations. Conclusions: This study reports for the first time the characterization of human myxoid liposarcoma xenografts that adequately mimic the biological and pharmacologic features of the human tumor. These models offer a useful tool for investigating the mechanism of selectivity of trabectedin, testing new combinations with this drug and evaluating novel therapies for myxoid liposarcoma. Clin Cancer Res; 16(20); 4958–67. ©2010 AACR.