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Pyriplatin, cis-diammine(pyridine)chloroplatinum(II), a platinum-based antitumor drug candidate, is a cationic compound with anticancer properties in mice and is a substrate for organic cation transporters that facilitate oxaliplatin uptake. Unlike cisplatin and oxaliplatin, which form DNA cross-links, pyriplatin binds DNA in a monofunctional manner. The antiproliferative effects of pyriplatin, alone and in combination with known anticancer drugs (paclitaxel, gemcitabine, SN38, cisplatin, and 5-fluorouracil), were evaluated in a panel of epithelial cancer cell lines, with direct comparison to cisplatin and oxaliplatin. The effects of pyriplatin on gene expression and platinum–DNA adduct formation were also investigated. Pyriplatin exhibited cytotoxic effects against human cell lines after 24 hours (IC50 = 171–443 μmol/L), with maximum cytotoxicity in HOP-62 non–small cell lung cancer cells after 72 hours (IC50 = 24 μmol/L). Pyriplatin caused a G2-M cell cycle block similar to that induced by cisplatin and oxaliplatin. Induction of apoptotsis and DNA damage response was supported by Annexin-V analysis and detection of phosphorylated Chk2 and H2AX. Treatment with pyriplatin increased CDKN1/p21 and decreased ERCC1 mRNA expression. On a platinum-per-nucleotide basis, pyriplatin–DNA adducts are less cytotoxic than those of cisplatin and oxaliplatin. The mRNA levels of genes implicated in drug transport and DNA damage repair, including GSTP1 and MSH2, correlate with pyriplatin cellular activity in the panel of cell lines. Synergy occurred for combinations of pyriplatin with paclitaxel. Because its spectrum of activity differs significantly from those of cisplatin or oxaliplatin, pyriplatin is a lead compound for developing novel drug candidates with cytotoxicity profiles unlike those of drugs currently in use. Mol Cancer Ther; 10(9); 1709–19. ©2011 AACR.

Differentially expressed genes in IMR5 cells after OTX015 and JQ1 treatment respectively

Mechanisms of reduced cell viability induced by OTX015 are cell line dependent. OTX015 reduces cell proliferation over time and induces cell cycle changes as well as apoptosis. (a) Representative photomicrographs of neuroblastoma cell lines treated with OTX015 for 72 h. Scale bar=200 µm. (b) The slope (1/h) of cell proliferation over time measured using xCELLigence of cell lines treated with OTX015. Significance was measured with the Student's t test. (c) Cell proliferation monitored using the xCELLigence system over time in neuroblastoma cell lines treated with 500 nM OTX015 (black) or DMSO control (grey). (d) Cell lines were treated 72 h with 500 nM OTX015 or DMSO, then fixed and stained with propidium iodide for flow cytometry. The distribution of OTX015-treated cells in different stages of the cell cycle is shown. (e) Fraction of apoptotic cells measured in the cell death ELISA assay after 72 h treatment with 250 nM or 500 nM OTX015 or DMSO control. Significant differences between treated cells versus controls were calculated by Student's t test. * p < 0.05, ** p < 0.01. (f) Cell proliferation measured in the BrdU ELISA after 72 h of treatment with 250 nM or 500 nM OTX015 or DMSO. Significant differences between treatment groups and the controls were calculated by Student's t test.

All H3K27Ac peaks called in non-promoter regions in IMR5

OTX015 has no significant effect on non-malignant human fibroblasts. (a) Representative pictures of human fibroblasts treated for 72 h with 500 nM OTX015 or DMSO control. Scale bar=100 µm. (b) Growth of fibroblasts treated with 500 nM OTX015 (black) or DMSO control (grey) monitored over 96 h using the xCELLigence system. The slope (1/h) of both curves was calculated, and did not show a significant difference (right) using the Student's t test.

Supplemental Figures S7. Supplemental Figures S7. Effects of JQ1 and OTX015 on BRD4 binding to MYD88 promoter region in DLBCL cell lines.

GSEA of gene sets describing general cellular processes after treatment with OTX015 and/or JQ1(GSEA, Broad institute)

BET inhibition preferentially disrupts expression of genes associated with super-enhancers. (a) ChIP-seq profiles for H3K27Ac binding at representative super-enhancer-associated gene loci, including MYCN, NCOR2, BCOR and GLI2, in MYCN-amplified IMR-5 cells. The x-axis shows genomic position and the y-axis the histone mark signal in units of reads per million per base pair (rpm/bp). The gene model is depicted below and scale bars above the binding profiles. (b) The Fisher exact test shows enrichment of super-enhancer associated genes among the downregulated genes (logFC < 0 and q < 0.05) by OTX015 or JQ1 treatment. (c) Cumulative distribution plots of the top 200 super-enhancer-associated genes and their fold-change measured using genes which are differentially regulated in IMR-5 cells by OTX015 treatment, JQ1 treatment or the overlap between these datasets (left to right). Plots show a shift towards negative logFC for super-enhancer associated genes (blue curves) compared to genes not associated with super-enhancers (black curves). (d) Box plots of log2-fold changes in the top 200 genes associated with super-enhancers (SE) and regular enhancers (non-SE) in genes differentially regulated (compared to DMSO-treated controls) in IMR-5 cells treated with OTX015, JQ1 or the overlap from both datasets (left to right). Statistical significance was determined using a two-sided Mann-Whitney test.

GSEA of cancer gene sets after treatment with OTX015 and/or JQ1(GSEA, Broad institute)

BET bromodomain inhibition leads to disruption of MYCN driven gene-expression programs even at high levels of MYCN. (a) Enrichment of the published gene expression signature for JQ1-treated human MYCN-amplified neuroblastoma cell lines (11) in differentially expressed genes in IMR-5 cells after treatment with OTX015, JQ1 or DMSO control. (b) Enrichment of the published gene expression signature for MYC target genes (16) in differentially expressed genes in IMR-5 cells after treatment with OTX015, JQ1 or DMSO control. (c) Enrichment of the published gene expression signature for JQ1-treated human MYCN-amplified neuroblastoma cell lines (11) in differentially expressed genes in mNB-A1 cells after treatment of with OTX015, JQ1 or DMSO control. (d) Enrichment of the published gene expression signature for MYC target genes (16) in differentially expressed genes in mNB-A1 cells after treatment with OTX015, JQ1 or DMSO control (* p < 0.05, ** p < 0.01, *** p < 0.001). (e) GSEA (version 2.0, Broad Institute) of differentially expressed genes in IMR5 cells after treatment with OTX015 or JQ1 using gene sets representing signatures of JQ1 as well as MYC target genes (11, 16).

Purpose: In cancer cells, the epigenome is often deregulated, and inhibition of the bromodomain and extra-terminal (BET) family of bromodomain-containing proteins is a novel epigenetic therapeutic approach. Preliminary results of an ongoing phase I trial have reported promising activity and tolerability with the new BET bromodomain inhibitor OTX015.Experimental Design: We assessed the preclinical activity of OTX015 as single agent and in combination in mature B-cell lymphoma models and performed in vitro and in vivo experiments to identify the mechanism of action and the genetic features associated with sensitivity to the compound.Results: OTX015 showed antiproliferative activity in a large panel of cell lines derived from mature B-cell lymphoid tumors with median IC50 of 240 nmol/L, without significant differences among the different histotypes. In vitro and in vivo experiments showed that OTX015 targeted NFKB/TLR/JAK/STAT signaling pathways, MYC- and E2F1-regulated genes, cell-cycle regulation, and chromatin structure. OTX015 presented in vitro synergism with several anticancer agents, especially with mTOR and BTK inhibitors. Gene expression signatures associated with different degrees of sensitivity to OTX015 were identified. Although OTX015 was mostly cytostatic, the compound induced apoptosis in a genetically defined subgroup of cells, derived from activated B-cell–like diffuse large B-cell lymphoma, bearing wtTP53, mutations in MYD88, and CD79B or CARD11.Conclusions: Together with the data coming from the ongoing phase I study, the in vitro and in vivo data presented here provide the basis for further clinical investigation of OTX015 as single agent and in combination therapies. Clin Cancer Res; 21(7); 1628–38. ©2015 AACR.

Supplemental Figures S1-2. Supplemental Figures S1: effects of OTX015 on cell cycle and cell growth in DLBCL cell lines. Supplemental Figures S2: effects of OTX015 on apoptosis in DLBCL cell lines.

Purpose: Targeting BET proteins was previously shown to have specific antitumoral efficacy against MYCN-amplified neuroblastoma. We here assess the therapeutic efficacy of the BET inhibitor, OTX015, in preclinical neuroblastoma models and extend the knowledge on the role of BRD4 in MYCN-driven neuroblastoma.Experimental Design: The efficacy of OTX015 was assessed in in vitro and in vivo models of human and murine MYCN-driven neuroblastoma. To study the effects of BET inhibition in the context of high MYCN levels, MYCN was ectopically expressed in human and murine cells. The effect of OTX015 on BRD4-regulated transcriptional pause release was analyzed using BRD4 and H3K27Ac chromatin immunoprecipitation coupled with DNA sequencing (ChIP-Seq) and gene expression analysis in neuroblastoma cells treated with OTX015 compared with vehicle control.Results: OTX015 showed therapeutic efficacy against preclinical MYCN-driven neuroblastoma models. Similar to previously described BET inhibitors, concurrent MYCN repression was observed in OTX015-treated samples. Ectopic MYCN expression, however, did not abrogate effects of OTX015, indicating that MYCN repression is not the only target of BET proteins in neuroblastoma. When MYCN was ectopically expressed, BET inhibition still disrupted MYCN target gene transcription without affecting MYCN expression. We found that BRD4 binds to super-enhancers and MYCN target genes, and that OTX015 specifically disrupts BRD4 binding and transcription of these genes.Conclusions: We show that OTX015 is effective against mouse and human MYCN-driven tumor models and that BRD4 not only targets MYCN, but specifically occupies MYCN target gene enhancers as well as other genes associated with super-enhancers. Clin Cancer Res; 22(10); 2470–81. ©2015 AACR.

List of all Super-enhancers identified in IMR5 cells

OTX015 effect on cell viability positively correlates with MYCN status. (a) IC50 of the IMR 5, Chp 134, Chp 212, SK N-BE(2), IMR-32, SK-N-BE, NB69, SK N AS and GI-M-EN neuroblastoma cell lines measured using MTT assays. (b) Maximum reduction of viability in IMR 5, Chp 134, Chp 212, SK N-BE(2), IMR-32, SK-N-BE, NB69, SK N AS and GI-M-EN cells treated for 72 h with 6 µM OTX015 and measured using MTT assays. (c) Relative MYCN mRNA (top) and protein (bottom) expression in all analyzed neuroblastoma cell lines. (d/e) The IC50 values of the cell lines shown in (a) were plotted against MYCN mRNA expression (d) or MYCN protein expression (e), which is shown in (c). Both graphs show weak anti-correlative tendencies in both cell lines (MYCN mRNA p=0.22, MYCN protein p=0.16).

Supplemental Table S4: List of gene-sets associated with the sensitivity to OTX015.

OTX015 reduces cell proliferation and induces apoptosis in MYCN amplified human xenografts. (a) Representative pictures of IMR5 xenograft tumor sections stained with hematoxylin/eosin, and immunohistochemical staining for apoptotic cells (cleaved caspase 3) and proliferating cells (Mib-1/Ki 67) are shown. Scale bar=250 µm. The relative fraction of positively stained cells for cleaved caspase 3 (b) and Mib-1 (c) were calculated from three representative images from each xenograft tumor and are shown as box plots. Statistical difference between groups was assessed by Student's t test. * p < 0.05, ** p < 0.01, *** p < 0.001.

Westermann et al. as well as Valentijn et al. MYCN target gene list and expression changes after OTX015 treatment as well as BRD4 binding

List of all genes from hg19 with changes in BRD4 binding using BRD4- ChIP-seq in IMR5 cells with changes after treatment with OTX015

Supplemental Figures S3-5. Supplemental Figures S3: the gene expression changes induced by OTX015 in DLBCL cell lines. Supplemental Figures S4: network of genes affected by OTX015. Supplemental Figures S5: similar biologic effects of OTX015 and JQ1.

Supplementary Figure Legends 1-2 from Epithelial-to-Mesenchymal Transition and Resistance to Ingenol 3-Angelate, a Novel Protein Kinase C Modulator, in Colon Cancer Cells

Supplementary Figure 1 from Epithelial-to-Mesenchymal Transition and Resistance to Ingenol 3-Angelate, a Novel Protein Kinase C Modulator, in Colon Cancer Cells

Supplementary Figure 2 from Epithelial-to-Mesenchymal Transition and Resistance to Ingenol 3-Angelate, a Novel Protein Kinase C Modulator, in Colon Cancer Cells

Acquired resistance to protein kinase C (PKC) modulators may explain the failure of clinical trials in patients with cancer. Herein, we established a human colon cancer cell line resistant to PEP005, a drug that inhibits PKCα and activates PKCδ. Colo205-R cells, selected by stepwise exposure to PEP005, were >300-fold more resistant to PEP005 than parental Colo205-S cells and were cross-resistant to phorbol 12-myristate 13-acetate, bryostatin, bistratene A, and staurosporine. No PKCα or PKCδ mutation was detected in Colo205-S and Colo205-R cells. Changes in Colo205-R cells were reminiscent of the epithelial-to-mesenchymal transition (EMT) phenotype. Accordingly, Colo205-R cells were more invasive than Colo205-S in Matrigel assays and in mouse xenografts. We also found an increased mRNA expression of several EMT genes, such as those encoding for transforming growth factor-β and vimentin, along with a decreased mRNA expression of genes involved in epithelial differentiation, such as CDH1 (E-cadherin), CLDN4 (claudin 4), S100A4, and MUC1, in Colo205-R compared with Colo205-S cells in vitro and in vivo. Interestingly, high expression of ET-1 was shown in Colo205-R cells and correlated with low sensitivity to PEP005 and staurosporine in a panel of 10 human cancer cell lines. Inhibition of the ET-1 receptor ETR-A with bosentan restored the antiproliferative effects of PEP005 in Colo205-R cells and decreased the invasive properties of this cell line. Exogenous exposure to ET-1 and silencing ET-1 expression using small interfering RNA modulated cell signaling in Colo205-S and Colo205-R. In summary, acquired resistance to PEP005 was associated with expression of EMT markers and activates the ET-1/ETR-A cell signaling. [Cancer Res 2009;69(10):4260–69]

The bromodomain and extra-C-terminal domain (BET) protein family is a class of epigenetic readers that recognize acetyl-lysine residues of histones, and their targeting with small molecules is a no...

International audience; Cancer stem cells (CSCs) contribute to disease progression and treatment failure in human cancers. The balance among self-renewal, differentiation, and senescence determines the expansion or progressive exhaustion of CSCs. Targeting these processes might lead to novel anticancer therapies. Here, we uncover a novel link between BRD4, mitochondrial dynamics, and self-renewal of prostate CSCs. Targeting BRD4 by genetic knockdown or chemical inhibitors blocked mitochondrial fission and caused CSC exhaustion and loss of tumorigenic capability. Depletion of CSCs occurred in multiple prostate cancer models, indicating a common vulnerability and dependency on mitochondrial dynamics. These effects depended on rewiring of the BRD4-driven transcription and repression of mitochondrial fission factor (Mff). Knockdown of Mff reproduced the effects of BRD4 inhibition, whereas ectopic Mff expression rescued prostate CSCs from exhaustion. This novel concept of targeting mitochondrial plasticity in CSCs through BRD4 inhibition provides a new paradigm for developing more effective treatment strategies for prostate cancer.

// Maria E. Riveiro 1 , Lucile Astorgues-Xerri 1 , Ramiro Vazquez 2 , Roberta Frapolli 2 , Ivo Kwee 3, 5 , Andrea Rinaldi 3 , Elodie Odore 6 , Keyvan Rezai 6 , Mohamed Bekradda 1 , Giorgio Inghirami 7, 9 , Maurizio D’Incalci 2 , Kay Noel 10 , Esteban Cvitkovic 1, 10 , Eric Raymond 11 , Francesco Bertoni 3, 12 1 Oncology Therapeutic Development, Clichy, France 2 IRCCS-Istituto di Ricerche Farmacologiche Mario Negri, Milan, Italy 3 Lymphoma and Genomics Research Program, IOR Institute of Oncology Research, Bellinzona, Switzerland 4 Dalle Molle Institute for Artificial Intelligence (IDSIA), Manno, Switzerland 5 SIB Swiss Institute of Bioinformatics, Lausanne, Switzerland 6 Radiopharmacology Department, Curie Institute - Rene Huguenin Hospital, Saint Cloud, France 7 Department of Pathology and Laboratory Medicine, Weill Cornell Medical College, New York, NY, USA 8 Department of Molecular Biotechnology and Health Science and Center for Experimental Research and Medical Studies (CeRMS), University of Turin, Turin, Italy 9 Department of Pathology, and NYU Cancer Center, New York University School of Medicine, New York, NY, USA 10 Oncoethix SA (now Oncoethix GmbH, a wholly owned subsidiary of Merck Sharp and Dohme Corp.), Lucerne, Switzerland 11 Medical Oncology Department, CHUV, Lausanne, Switzerland 12 Oncology Institute of Southern Switzerland (IOSI), Bellinzona, Switzerland Correspondence to: Maria E Riveiro, email: eugenia.riveiro@oncotd.com Keywords: OTX015 (MK-8628), bromodomain, NSCLC, SCLC, KRAS Received: January 21, 2016 Accepted: October 14, 2016 Published: November 07, 2016 ABSTRACT Inhibitors targeting epigenetic control points of oncogenes offer a potential mean of blocking tumor progression in small cell and non-small cell lung carcinomas (SCLC, NSCLC). OTX015 (MK-8628) is a BET inhibitor selectively blocking BRD2/3/4. OTX015 was evaluated in a panel of NSCLC or SCLC models harboring different oncogenic mutations. Cell proliferation inhibition and cell cycle arrest were seen in sensitive NSCLC cells. MYC and MYCN were downregulated at both the mRNA and protein levels. In addition, OTX015-treatment significantly downregulated various stemness cell markers, including NANOG, Musashi-1, CD113 and EpCAM in H3122-tumors in vivo . Conversely, in SCLC models, weak antitumor activity was observed with OTX015, both in vitro and in vivo . No predictive biomarkers of OTX015 activity were identified in a large panel of candidate genes known to be affected by BET inhibition. In NSCLC models, OTX015 was equally active in both EML4-ALK positive and negative cell lines, whereas in SCLC models the presence of functional RB1 protein, which controls cell progression at G1, may be related to the final biological outcome of OTX015. Gene expression profiling in NSCLC and SCLC cell lines showed that OTX015 affects important genes and pathways with a very high overlapping between both sensitive and resistant cell lines. These data support the rationale for the OTX015 Phase Ib (NCT02259114) in solid tumors, where NSCLC patients with rearranged ALK gene or KRAS-positive mutations are currently being treated.

// Michela Boi 1, 2, * , Maria Todaro 1, 2, * , Valentina Vurchio 1 , Shao Ning Yang 3 , John Moon 3 , Ivo Kwee 4, 5, 6 , Andrea Rinaldi 4 , Heng Pan 7, 8 , Ramona Crescenzo 1, 2 , Mangeng Cheng 9 , Leandro Cerchietti 3 , Olivier Elemento 7, 8 , Maria E. Riveiro 10 , Esteban Cvitkovic 10, 11 , Francesco Bertoni 4, 12 , Giorgio Inghirami 1, 2, 13 , The AIRC 5xMille Consortium ‘Genetics-Driven Targeted Management of Lymphoid Malignancies’ 1 Department of Molecular Biotechnology and Health Science and Center for Experimental Research and Medical Studies (CeRMS), University of Torino, Torino, Italy 2 Department of Pathology and Laboratory Medicine, Weill Cornell Medical College, New York, NY, USA 3 Joan and Sanford I. Weill Department of Medicine, Weill Cornell Medical College, New York, NY, USA 4 Lymphoma and Genomics Research Program, IOR Institute of Oncology Research, Bellinzona, Switzerland 5 Dalle Molle Institute for Artificial Intelligence (IDSIA), Manno, Switzerland 6 Swiss Institute of Bioinformatics (SIB), Lausanne, Switzerland 7 Institute for Computational Biomedicine, Department of Physiology and Biophysics, Weill Cornell Medical College, New York, NY, USA 8 Institute for Precision Medicine, Weill Cornell Medical College, New York, NY, USA 9 In Vitro Pharmacology, Merck Research Laboratory, Boston, MA, USA 10 Oncology Therapeutic Development, Clichy, France 11 Oncoethix SA (Now Oncoethix GmbH, A Wholly Owned Subsidiary of Merck Sharp & Dohme Corp.), Lucerne, Switzerland 12 IOSI Oncology Institute of Southern Switzerland, Bellinzona, Switzerland 13 Department of Pathology, and NYU Cancer Center, New York University School of Medicine, New York, NY, USA * These authors have contributed equally to this work Correspondence to: Giorgio Inghirami, email: ggi9001@med.cornell.edu Francesco Bertoni, email: frbertoni@mac.com Keywords: anaplastic large cell lymphoma, BRD inhibitor, OTX015/MK-8628, tyrosine kinase inhibitor, gene expression profiling Received: July 07, 2016 Accepted: September 19, 2016 Published: October 25, 2016 ABSTRACT Anaplastic large cell lymphomas (ALCL) represent a peripheral T-cell lymphoma subgroup, stratified based on the presence or absence of anaplastic lymphoma kinase (ALK) chimeras. Although ALK-positive ALCLs have a more favorable outcome than ALK-negative ALCL, refractory and/or relapsed forms are common and novel treatments are needed. Here we investigated the therapeutic potential of a novel bromodomain inhibitor, OTX015/MK-8628 in ALK-positive ALCLs. The effects of OTX015 on a panel of ALK+ ALCL cell lines was evaluated in terms of proliferation, cell cycle and downstream signaling, including gene expression profiling analyses. Synergy was tested with combination targeted therapies. Bromodomain inhibition with OTX015 led primarily to ALCL cell cycle arrest in a dose-dependent manner, along with downregulation of MYC and its downstream regulated genes. MYC overexpression did not compensate this OTX015-mediated phenotype. Transcriptomic analysis of OTX015-treated ALCL cells identified a gene signature common to various hematologic malignancies treated with bromodomain inhibitors, notably large cell lymphoma. OTX015-modulated genes included transcription factors ( E2F2 , NFKBIZ, FOS , JUNB, ID1, HOXA5 and HOXC6 ) , members of multiple signaling pathways ( ITK , PRKCH, and MKNK2 ), and histones (clusters 1-3). Combination of OTX015 with the Bruton’s tyrosine kinase (BTK) inhibitor ibrutinib led to cell cycle arrest then cell death, and combination with suboptimal doses of the ALK inhibitor CEP28122 caused cell cycle arrest. When OTX015 was associated with GANT61, a selective GLI1/2 inhibitor, C1156Y-resistant ALK ALCL growth was impaired. These findings support OTX015 clinical trials in refractory ALCL in combination with inhibitors of interleukin-2-inducible kinase or SHH/GLI1.

It has recently been reported that a large proportion of human malignant pleural mesothelioma (MPM) cell lines and patient tissue samples present high expression of the c-MYC oncogene. This gene drives several tumorigenic processes and is overexpressed in many cancers. Although c-MYC is a strategic target to restrain cancer processes, no drugs acting as c-MYC inhibitors are available. The novel thienotriazolodiazepine small-molecule bromodomain inhibitor OTX015/MK-8628 has shown potent antiproliferative activity accompanied by c-MYC downregulation in several tumor types. This study was designed to evaluate the growth inhibitory effect of OTX015 on patient-derived MPM473, MPM487 and MPM60 mesothelioma cell lines and its antitumor activity in three patient-derived xenograft models, MPM473, MPM487 and MPM484, comparing it with cisplatin, gemcitabine and pemetrexed, three agents which are currently used to treat MPM in the clinic. OTX015 caused a significant delay in cell growth both in vitro and in vivo. It was the most effective drug in MPM473 xenografts and showed a similar level of activity as the most efficient treatment in the other two MPM models (gemcitabine in MPM487 and cisplatin in MPM484). In vitro studies showed that OTX015 downregulated c-MYC protein levels in both MPM473 and MPM487 cell lines. Our findings represent the first evidence of promising therapeutic activity of OTX015 in mesothelioma.

// Eugenio Gaudio 1 , Chiara Tarantelli 1 , Maurilio Ponzoni 2 , Elodie Odore 3 , Keyvan Rezai 3 , Elena Bernasconi 1 , Luciano Cascione 1, 4 , Andrea Rinaldi 1 , Anastasios Stathis 4 , Eugenia Riveiro 5 , Esteban Cvitkovic 5 , Emanuele Zucca 4 , Francesco Bertoni 1, 4 1 Lymphoma and Genomics Research Program, Institute of Oncology Research (IOR), Bellinzona, Switzerland 2 San Raffaele Scientific Institute, Milan, Italy 3 Institut Curie, Hopital Rene Huguenin, Saint-Cloud, France 4 Oncology Institute of Southern Switzerland (IOSI), Bellinzona, Switzerland 5 Oncology Therapeutic Development, Clichy, France Correspondence to: Francesco Bertoni, email: frbertoni@mac.com Keywords: BET inhibitor, ibrutinib, rituximab, vorinostat, everolimus Received: April 28, 2016 Accepted: July 07, 2016 Published: August 1, 2016 ABSTRACT The bromodomain inhibitor OTX015 (MK-8628) has shown anti-lymphoma activity as a single agent in both the preclinical and clinical settings, as well as in vitro synergism with several anticancer agents. Here, we report in vivo data for OTX015 in combination with the histone deacetylase inhibitor vorinostat, the Bruton’s tyrosine kinase inhibitor ibrutinib, the anti-CD20 monoclonal antibody rituximab, and the mTOR inhibitor everolimus in a diffuse large B cell lymphoma model. The antitumor effect of OTX015-containing combinations in SU-DHL-2 xenografts in mice was much stronger than the activity of the corresponding single agents with almost complete tumor eradication for all four combinations. Pharmacokinetic analyses showed similar OTX015 levels in plasma and tumor samples of approximately 1.5 μM, which is equivalent to the concentration showing strong in vitro activity. For all four combinations, mean terminal levels of the bromodomain inhibitor differed from those in mice exposed to single agent OTX015, indicating a need for thorough pharmacokinetic investigations in phase I combination studies. In conclusion, our results provide a strong rationale to explore OTX015-containing combinations in the clinical lymphoma setting.

Bromodomain and extraterminal (BET) bromodomain (BRD) proteins are epigenetic readers that bind to acetylated lysine residues on chromatin, acting as co-activators or co-repressors of gene expression. BRD2 and BRD4, members of the BET family, are significantly increased in glioblastoma multiforme (GBM), the most common primary adult brain cancer. OTX015 (MK-8628), a novel BRD2/3/4 inhibitor, is under evaluation in dose-finding studies in solid tumors, including GBM. We investigated the pharmacologic characteristics of OTX015 as a single agent and combined with targeted therapy or conventional chemotherapies in glioblastoma cell lines. OTX015 displayed higher antiproliferative effects compared to its analog JQ1, with GI50 values of approximately 0.2 µM. In addition, C-MYC and CDKN1A mRNA levels increased transiently after 4 h-exposure to OTX015, while BRD2, SESN3, HEXIM-1, HIST2H2BE, and HIST1H2BK were rapidly upregulated and sustained after 24 h. Studies in three additional GBM cell lines supported the antiproliferative effects of OTX015. In U87MG cells, OTX015 showed synergistic to additive activity when administered concomitant to or before SN38, temozolomide or everolimus. Single agent oral OTX015 significantly increased survival in mice bearing orthotopic or heterotopic U87MG xenografts. OTX015 combined simultaneously with temozolomide improved mice survival over either single agent. The passage of OTX015 across the blood-brain barrier was demonstrated with OTX015 tumor levels 7 to 15-fold higher than in normal tissues, along with preferential binding of OTX015 to tumor tissue. The significant antitumor effects seen with OTX015 in GBM xenograft models highlight its therapeutic potential in GBM patients, alone or combined with conventional chemotherapies.

Purpose: Targeting BET proteins was previously shown to have specific antitumoral efficacy against MYCN-amplified neuroblastoma. We here assess the therapeutic efficacy of the BET inhibitor, OTX015, in preclinical neuroblastoma models and extend the knowledge on the role of BRD4 in MYCN-driven neuroblastoma. Experimental Design: The efficacy of OTX015 was assessed in in vitro and in vivo models of human and murine MYCN-driven neuroblastoma. To study the effects of BET inhibition in the context of high MYCN levels, MYCN was ectopically expressed in human and murine cells. The effect of OTX015 on BRD4-regulated transcriptional pause release was analyzed using BRD4 and H3K27Ac chromatin immunoprecipitation coupled with DNA sequencing (ChIP-Seq) and gene expression analysis in neuroblastoma cells treated with OTX015 compared with vehicle control. Results: OTX015 showed therapeutic efficacy against preclinical MYCN-driven neuroblastoma models. Similar to previously described BET inhibitors, concurrent MYCN repression was observed in OTX015-treated samples. Ectopic MYCN expression, however, did not abrogate effects of OTX015, indicating that MYCN repression is not the only target of BET proteins in neuroblastoma. When MYCN was ectopically expressed, BET inhibition still disrupted MYCN target gene transcription without affecting MYCN expression. We found that BRD4 binds to super-enhancers and MYCN target genes, and that OTX015 specifically disrupts BRD4 binding and transcription of these genes. Conclusions: We show that OTX015 is effective against mouse and human MYCN-driven tumor models and that BRD4 not only targets MYCN, but specifically occupies MYCN target gene enhancers as well as other genes associated with super-enhancers. Clin Cancer Res; 22(10); 2470–81. ©2015 AACR.

Background The outcome of patients affected by mantle cell lymphoma (MCL) has improved in recent years, but there is still a need for novel treatment strategies for these patients. Human cancers, including MCL, present recurrent alterations in genes that encode transcription machinery proteins and of proteins involved in regulating chromatin structure, providing the rationale to pharmacologically target epigenetic proteins. The Bromodomain and Extra Terminal domain (BET) family proteins act as transcriptional regulators of key signalling pathways including those sustaining cell viability. Birabresib (MK-8628/OTX015) has shown antitumour activity in different preclinical models and has been the first BET inhibitor to successfully undergo early clinical trials. Materials and methods The activity of birabresib as a single agent and in combination, as well as its mechanism of action was studied in MCL cell lines. Results Birabresib showed in vitro and in vivo activities, which appeared mediated via downregulation of MYC targets, cell cycle and NFKB pathway genes and were independent of direct downregulation of CCND1. Additionally, the combination of birabresib with other targeted agents (especially pomalidomide, or inhibitors of BTK, mTOR and ATR) was beneficial in MCL cell lines. Conclusion Our data provide the rationale to evaluate birabresib in patients affected by MCL.

OTX015 (MK-8628) is a novel inhibitor of the bromodomain and extraterminal (BET)-bromodomain (BRD) protein family, binding specifically to bromodomains BRD2/3/4 and impacting the epigenetic regulation of several oncogenes. We characterized the pharmacokinetics of this first-in-class BET-BRD inhibitor administered as a single agent, including population pharmacokinetic modelling. A dose-escalation, phase Ib study was performed with oral OTX015 in patients with haematologic malignancies, at doses starting from 10 mg once daily (QD) with continuous or discontinuous schedules. Five or eight blood samples were collected per patient for pharmacokinetic analysis. OTX015 plasma concentrations were determined using validated ultra-performance liquid chromatography–tandem mass spectrometry (UPLC–MS/MS) and analysed using a nonlinear mixed-effects modelling software program. A population pharmacokinetic model was fitted to the data, and patient demographics and clinical chemistry parameters were tested as predictive covariates on the model parameters. Blood samples were analysed from 81 patients treated with OTX015 at doses ranging from 10 to 160 mg QD or 40 mg twice daily (BID), and 633 time–plasma concentrations were available for analysis. A one-compartment open model with linear elimination adequately described OTX015 pharmacokinetics. The most significant covariate was lean body mass (LBM), which decreased the between-subject variability in apparent total body clearance (CL) and the volume of distribution (V). The estimated pharmacokinetic parameters were the absorption rate constant (k a) = 0.731 h−1, V = 71.4 L and CL = 8.47 L·h−1. The pharmacokinetics of oral OTX015 in patients with haematologic malignancies can be described with a one-compartment model. Population pharmacokinetic modelling of OTX015 plasma concentrations showed that LBM influences V and CL. These findings do not suggest the need for dose adjustment.

It has recently been reported that a large proportion of human malignant pleural mesothelioma (MPM) cell lines and patient tissue samples present high expression of the c-MYC oncogene. This gene drives several tumorigenic processes and is overexpressed in many cancers. Although c-MYC is a strategic target to restrain cancer processes, no drugs acting as c-MYC inhibitors are available. The novel thienotriazolodiazepine small-molecule bromodomain inhibitor OTX015/MK-8628 has shown potent antiproliferative activity accompanied by c-MYC downregulation in several tumor types. This study was designed to evaluate the growth inhibitory effect of OTX015 on patient-derived MPM473, MPM487 and MPM60 mesothelioma cell lines and its antitumor activity in three patient-derived xenograft models, MPM473, MPM487 and MPM484, comparing it with cisplatin, gemcitabine and pemetrexed, three agents which are currently used to treat MPM in the clinic. OTX015 caused a significant delay in cell growth both in vitro and in vivo. It was the most effective drug in MPM473 xenografts and showed a similar level of activity as the most efficient treatment in the other two MPM models (gemcitabine in MPM487 and cisplatin in MPM484). In vitro studies showed that OTX015 downregulated c-MYC protein levels in both MPM473 and MPM487 cell lines. Our findings represent the first evidence of promising therapeutic activity of OTX015 in mesothelioma.

OTX008 is a galectin-1-targeting compound, currently undergoing a phase I clinical trial. This study aimed at investigating OTX008 pharmacokinetics (PK) and antineoplastic activity.Pharmacokinetics and activity of OTX008 were analyzed in the human ovarian carcinoma A2780-1A9 and glioblastoma U87MG xenografted in nude mice. In vitro, OTX008 was tested on tumor and endothelial cells.After 5 mg/kg i.v., OTX008 achieved plasma Cmax of 14.39 μg/mL, distributed rapidly, and was eliminated with a half-life of 31.4 h. Tumor OTX008 Cmax (1.65 μg/g, 1.76 μM), achieved at 0.5 h, remained high at 24 h (0.516 μg/g, 0.55 μM) with AUC of 15.76 μg/g*h. OTX008 accumulated in the tumor after repeated administrations achieving a concentration of 2.3 μM, compatible with the concentrations active in vitro. OTX008 (5 mg/kg i.v., every other day for 3 weeks) inhibited the in vivo growth of A2780-1A9, whereas U87MG was not sensitive. In vitro, OTX008 affected endothelial cell proliferation, motility, invasiveness, and cord formation. Tumor cell proliferation was also inhibited, with differences in sensitivity among cell lines (IC50 from 1 to 190 μM). OTX008 potentiated the activity of the tyrosine kinase inhibitor sunitinib on A2780-1A9 in vivo and in vitro, where the combination showed synergistic (endothelial cells) and additive (A2780-1A9) antiproliferative activity, indicating that the combination targets both the tumor and vascular compartments.OTX008-alone or in combination with sunitinib-has a favorable PK and antineoplastic activity on selected tumor models through the effects on both endothelial and tumor cells.

Triple-negative breast cancer (TNBC) is an aggressive and heterogeneous subgroup of breast tumors clinically defined by the lack of estrogen, progesterone and HER2 receptors, limiting the use of the targeted therapies employed in other breast malignancies. Recent evidence indicates that c-MYC is a key driver of TNBC. The BET-bromodomain inhibitor OTX015 (MK-8628) has potent antiproliferative activity accompanied by c-MYC down-regulation in several tumor types, and has demonstrated synergism with the mTOR inhibitor everolimus in different models. The aim of this study was to evaluate the anti-tumor activity of OTX015 as single agent and in combination with everolimus in TNBC models. OTX015 was assayed in three human TNBC-derived cell lines, HCC1937, MDA-MB-231 and MDA-MB-468, all showing antiproliferative activity after 72 h (GI50 = 75-650 nM). This was accompanied by cell cycle arrest and decreased expression of cancer stem cells markers. However, c-MYC protein and mRNA levels were only down-regulated in MDA-MB-468 cells. Gene set enrichment analysis showed up-regulation of genes involved in epigenetic control of transcription, chromatin and the cell cycle, and down-regulation of stemness-related genes. In vitro, combination with everolimus was additive in HCC1937 and MDA-MB-231 cells, but antagonistic in MDA-MB-468 cells. In MDA-MB-231 murine xenografts, tumor mass was significantly (p < 0.05) reduced by OTX015 with respect to vehicle-treated animals (best T/C = 40.7%). Although everolimus alone was not active, the combination was more effective than OTX015 alone (best T/C = 20.7%). This work supports current clinical trials with OTX015 in TNBC (NCT02259114).

ProLindac (AP5346) is DACH (diaminocyclohexane) platinum polymer prodrug currently in phase II clinical development. It uses a 25 kDa polymer delivery vehicle based on hydroxypropylmethacrylamide (HPMA) to target the active form of the approved drug oxaliplatin to tumors. The pH-sensitive linker that binds platinum to the polymer releases platinum more rapidly in low pH environments, as found typically in many tumors. This review summarizes the development of ProLindac to date, including preclinical efficacy studies, the phase I monotherapy clinical study in patients with solid tumors, and the phase I/II monotherapy study in patients with recurrent ovarian cancer. Both preclinical and clinical study data indicate that ProLindac exhibits efficacy at least equal to, and likely superior to oxaliplatin, while demonstrating excellent tolerability. Additional clinical studies of ProLindac used in combination with other chemotherapeutic agents are planned.

Acquired resistance to protein kinase C (PKC) modulators may explain the failure of clinical trials in patients with cancer. Herein, we established a human colon cancer cell line resistant to PEP005, a drug that inhibits PKCα and activates PKCδ. Colo205-R cells, selected by stepwise exposure to PEP005, were >300-fold more resistant to PEP005 than parental Colo205-S cells and were cross-resistant to phorbol 12-myristate 13-acetate, bryostatin, bistratene A, and staurosporine. No PKCα or PKCδ mutation was detected in Colo205-S and Colo205-R cells. Changes in Colo205-R cells were reminiscent of the epithelial-to-mesenchymal transition (EMT) phenotype. Accordingly, Colo205-R cells were more invasive than Colo205-S in Matrigel assays and in mouse xenografts. We also found an increased mRNA expression of several EMT genes, such as those encoding for transforming growth factor-β and vimentin, along with a decreased mRNA expression of genes involved in epithelial differentiation, such as CDH1 (E-cadherin), CLDN4 (claudin 4), S100A4, and MUC1, in Colo205-R compared with Colo205-S cells in vitro and in vivo. Interestingly, high expression of ET-1 was shown in Colo205-R cells and correlated with low sensitivity to PEP005 and staurosporine in a panel of 10 human cancer cell lines. Inhibition of the ET-1 receptor ETR-A with bosentan restored the antiproliferative effects of PEP005 in Colo205-R cells and decreased the invasive properties of this cell line. Exogenous exposure to ET-1 and silencing ET-1 expression using small interfering RNA modulated cell signaling in Colo205-S and Colo205-R. In summary, acquired resistance to PEP005 was associated with expression of EMT markers and activates the ET-1/ETR-A cell signaling. [Cancer Res 2009;69(10):4260–69]

Purpose: In cancer cells, the epigenome is often deregulated, and inhibition of the bromodomain and extra-terminal (BET) family of bromodomain-containing proteins is a novel epigenetic therapeutic approach. Preliminary results of an ongoing phase I trial have reported promising activity and tolerability with the new BET bromodomain inhibitor OTX015. Experimental Design: We assessed the preclinical activity of OTX015 as single agent and in combination in mature B-cell lymphoma models and performed in vitro and in vivo experiments to identify the mechanism of action and the genetic features associated with sensitivity to the compound. Results: OTX015 showed antiproliferative activity in a large panel of cell lines derived from mature B-cell lymphoid tumors with median IC50 of 240 nmol/L, without significant differences among the different histotypes. In vitro and in vivo experiments showed that OTX015 targeted NFKB/TLR/JAK/STAT signaling pathways, MYC- and E2F1-regulated genes, cell-cycle regulation, and chromatin structure. OTX015 presented in vitro synergism with several anticancer agents, especially with mTOR and BTK inhibitors. Gene expression signatures associated with different degrees of sensitivity to OTX015 were identified. Although OTX015 was mostly cytostatic, the compound induced apoptosis in a genetically defined subgroup of cells, derived from activated B-cell–like diffuse large B-cell lymphoma, bearing wtTP53, mutations in MYD88, and CD79B or CARD11. Conclusions: Together with the data coming from the ongoing phase I study, the in vitro and in vivo data presented here provide the basis for further clinical investigation of OTX015 as single agent and in combination therapies. Clin Cancer Res; 21(7); 1628–38. ©2015 AACR.

Protein kinase C (PKC) family comprises more than 12 serine-/threonine-specific isoenzymes. PKC isoenzymes play a complex role in the transduction of signal from tyrosine kinase receptor modulating proliferation, cell cycle, apoptosis, invasion, differentiation, and senescence in both cancer cells and endothelial cells. Thereby, inhibition and/or activation of specific PKCs is thought to control tumor growth by interacting directly with cancer cells and indirectly by blocking tumor angiogenesis. Furthermore, PKCs are known to modulate multi-drug resistance, providing a rational for the combination of PKCs modulators with classical cytotoxic drugs. During the past few years, preclinical and clinical data with first-generation PKC inhibitors/activators provided insight that PKCs may indeed represent attractive targets for the discovery of small molecules with new anticancer properties. In this review, we will provide an overview on the current understanding of PKC participation in chemotherapeutic resistance, the possible implications in cancer treatment, and the potential of most recent PKC inhibitors in molecular cancer therapeutics.

Resume Objectifs — L’efficacite et le benefice d’une chimiotherapie de seconde ligne dans le traitement des adenocarcinomes pancreatiques n’ont jamais ete demontres bien que ce traitement soit regulierement prescrit. Malades et methodes — Une etude de phase II randomisee evaluant une chimiotherapie par oxaliplatine (OXA), 5-fluorouracile infusionnel (5-FU) ou la combinaison des deux (OXFU) en traitement de premiere ligne des adenocarcinomes pancreatiques avances a ete realisee. Dans cette etude, une chimiotherapie de seconde ligne par OXFU (OXA 130 mg/m 2 IV 2h plus 5-FU 1000 mg/m 2 /j en perfusion continue de J1 a J4 toutes les 3 semaines) etait proposee aux malades progressant sous traitement par OXA ou 5-FU seuls. Resultats — Dix-huit des 32 malades (12 hommes, âge median 57 ans) en progression tumorale apres monochimiotherapie en premiere ligne ont recu la combinaison OXFU en traitement de seconde ligne. Le statut de performance selon l’OMS etait superieur ou egal a deux dans 61 % des cas. Aucune reponse objective n’a ete observee et trois patients (17 %) ont eu une stabilisation de leur maladie. Le delai median jusqu’a progression depuis le debut de la chimiotherapie de seconde ligne etait de 0,9 mois. La survie mediane etait de 4,9 mois depuis le debut du traitement de premiere ligne et de 1,3 mois depuis le debut du traitement de seconde ligne. Conclusion — Les resultats de cette etude apportent des arguments en faveur d’un role modeste de la chimiotherapie de seconde ligne dans le traitement des adenocarcinomes pancreatiques avances.

A phase II study was conducted to evaluate the safety and efficacy of an oxaliplatin (OXA)/vinorelbine (VNB) combination in metastatic breast cancer (MBC) patients pre-treated with anthracyclines and taxanes. Patients received OXA at 130 mg/m 2 (2-h i.v.), day 1, and VNB days 1 and 8 at 24-26 mg/m 2 repeated every 3 weeks. Forty-two patients (median age 54; 64% with liver metastasis, 67% taxane resistant/refractory and 38% anthracycline resistant/refractory) were treated. A median of 4 cycles of treatment was given per patient, with 31% receiving 6 or more. Eleven partial responses and 16 patients with stable disease (five lasting more than 4 months) in 41 eligible patients were seen, for an overall response rate of 26.8% (95% confidence interval 14.2-42.9). Median follow-up was 15.9 months (7.2-30.6), median time to progression was 3.4 months and estimated overall survival was 12.7 months (20 events). Thirty-three patients experienced (National Cancer Institute Common Toxicity Criteria version 2) grade 3-4 neutropenia (one case of febrile neutropenia) and three patients had severe constipation requiring hospitalization. Nine patients developed grade 3 OXA-specific neurotoxicity. There were no treatment-related deaths. We conclude that OXA 130 mg/m 2 (day 1) and VNB 24 mg/m 2 (day 1 and 8) combination given every 3 weeks is effective with a good safety profile in MBC patients previously treated with anthracyclines and taxanes.

Purpose: This study assessed the cytotoxic effects of irofulven in combination with oxaliplatin and cisplatin in a panel of human cancer cell lines. Methods: Growth inhibition studies were performed using the human HT29 colon cancer cell line, irofulven-resistant derivative HT29/IF2, breast cancer cell line MCF7, and ovarian cancer line CAOV3. Irofulven–oxaliplatin combinations were compared with irofulven–cisplatin combinations in the same cell lines using similar experimental settings. Cells were exposed for 1 h to irofulven and then for 24 h to oxaliplatin or cisplatin and vice versa. Results: Single agent irofulven displayed cytotoxic effects against human colon HT29 cells, human breast cancer cell lines including MCF7, SKBR3, and ZR-75-1, and human ovarian cancer cell lines CAOV3, OVCAR3, and IGROV1, with OVCAR3 being the most sensitive cancer cell line (IC50: 2.4 μM). In all tested cell lines the oxaliplatin–irofulven combination led to clear evidence of synergistic activity. In HT29 and HT29/IF2, the sequence oxaliplatin followed by irofulven appears to be the most effective whereas in MCF7 cells, irofulven given prior to or simultaneously with oxaliplatin is more effective than the other schedule. The combination displays additive activity toward CAOV3 ovarian cells when irofulven was administered prior to or simultaneously with oxaliplatin and partially synergistic when oxaliplatin was followed by irofulven. In most of the cell lines, the sequence oxaliplatin followed by irofulven appears to be the most effective as compared to other schedules. A combination of irofulven with cisplatin has the same efficacy as with oxaliplatin for the same cell lines. Cell cycle studies show that irofulven increases the proportion of cells in the S phase. Cisplatin–irofulven and oxaliplatin–irofulven combinations block cells in G1/S and potently induce apoptosis. Conclusion: Irofulven displays synergistic antiproliferative and pro-apoptotic effects when combined with oxaliplatin over a broad range of concentrations in human colon and breast cancer cells. Acquired resistance to irofulven has limited impact on the effects of cisplatin–irofulven and oxaliplatin–irofulven combinations. Based on these data, irofulven–oxaliplatin and cisplatin–irofulven combinations will be further explored in clinical trials, favoring the use schedules of oxaliplatin given prior to irofulven in patients with cancer.

Purpose: Irofulven (6-hydroxymethylacylfulvene) is a novel agent, derived from illudin S, with potent apoptotic effects in preclinical models. In the Phase I trial evaluating intermittent weekly schedules, visual symptoms were dose limiting. The aim of this analysis was to better characterize the visual adverse events of irofulven and provide treatment guidelines. Experimental Design: Clinical data from 277 patients entered in single-agent Phase I to II clinical trials who received irofulven on days 1 and 15 every 4 weeks; days 1, 8, and 15 every 4 weeks; or days 1 and 8 every 3 weeks were included in this multiparameter analysis. Results: Overall, 74 patients (27%) experienced visual symptoms. The most frequently reported symptoms were flashing lights (12% of patients), blurred vision (9%), and photosensitivity (8%). Grade 3 toxicity was observed in 12 patients (4%). The incidence and severity of visual events were dose dependent, with no grade 3 visual events occurring at doses ≤0.50 mg/kg and grade 1 to 2 events in only 12% and 8% of patients, at doses of ≤0.50 mg/kg and ≤20 mg/m2, respectively. Grade 1 to 2 toxicity was reversible in most patients. Abnormal electroretinogram and abnormal visual fields were noted after irofulven treatment in 24 of 39 patients (62%) and 15 of 26 patients (58%), respectively. All but 1 patient who had electroretinogram assessment received doses >0.50 mg/kg. Clinical examination and visual field assessment were found to be better correlated with symptoms and appear to be more appropriate for surveillance of irofulven retinal symptoms than electroretinograms. Conclusions: On the basis of retained antitumor activity and reversibility of grade 1 and 2 visual symptoms at lower doses, it appears that an irofulven dose of ≤0.50 mg/kg or ≤20 mg/m2, not to exceed 50 mg in a single dose, given as a 30-minute infusion on days 1 and 8 every 3 weeks or days 1 and 15 every 4 weeks minimizes the frequency and severity of visual symptoms.

Background: A randomized phase II, open-label multicenter study evaluating oxaliplatin alone (OXA), infusional 5-fluorouracil alone (5-FU) and an oxaliplatin/infusional 5-FU combination (OXFU) in untreated, advanced pancreatic carcinoma (APC). Patients and methods: Chemotherapy-naive patients with advanced or metastatic, histologically/cytologically proven pancreatic carcinoma with measurable disease, received OXA [130 mg/m 2 , 2-h intravenous (i.v.) infusion] alone, OXA combined with 5-FU (1000 mg/m 2 /day, continuous i.v., days 1–4), or 5-FU alone, every 3 weeks. Results: Sixty-three patients (42 males/21 females) were treated: 17 patients/52 cycles OXA, 31 patients/ 175 cycles OXFU, 15 patients/41 cycles 5-FU, with a median of three, six and two cycles/patient, respectively. Patient characteristics were similar in all arms. Median age was 57 years (range 21–75), and 83% of patients had PS 0–1. Most patients (62%) had moderate to well-differentiated tumors, 90% had metastatic disease, 81% with liver metastases. All responses (three partial responses; WHO) occurred in the OXFU arm (10% response rate). Five of 32 patients evaluable for clinical benefit were responders (OXA, 14%; OXFU, 21%). Median time to progression and overall survival were higher in the combination arm (4.2 and 9.0 months, respectively) than either single-agent arm (OXA, 2.0 and 3.4 months; 5-FU, 1.5 and 2.4 months, respectively). Moderate hematotoxicity without morbidity was seen in all arms. Two OXFU patients had grade 3 oxaliplatin neurosensory toxicity. Conclusions: With a 10% response rate, median overall survival of 9 months and an encouraging safety profile, the OXFU combination is effective, appears superior to infusional 5-FU and warrants further studies in APC patients.

Background Phase I and pharmacokinetic study to determine the maximal tolerated dose and the recommended dose, as well as the optimal sequence of a carboplatin/oxaliplatin combination delivered every 3 weeks. Patients and methods Patients received either carboplatin [area under the curve (AUC)-based individually calculated dose (starting dose AUC 4 mg·min/ml), 1 h intravenous (i.v.) infusion] followed by oxaliplatin(110 mg/m2, 2 h i.v. infusion), every 3 weeks, or the reverse sequence. Results Sixteen patients were included and only one dose level was assessed. In group A, 10 patients received 23 cycles of carboplatin followed by oxaliplatin. In group B, 6 patients received 20 cycles with the reverse sequence. Delayed recovery from hematological toxicities was treatment-limiting, with mainly moderate thrombocytopenia and neutropenia as dose-limiting toxicities for group A (5 of 10 patients for each) and thrombocytopenia for group B (3 of 6 patients). No febrile neutropenia or grade 3/4 non-hematological toxicity occurred. Pharmacokinetic analysis showed similar mean total platinum AUCs for the two groups: 37.2 ± 13.7 and 33.6 ± 9.9 mg·h/l, respectively. One complete response and two partial responses (World Health Organization–International Union Against Cancer criteria, response rate 18.8%) were seen in ovarian, Fallopian and neuroendocrine carcinomas, respectively. Conclusions This platinum combination appears feasible and active at the dose of AUC 4 mg·min/ml for carboplatin (Chatelut formula) and oxaliplatin 110 mg/m2; however, it does not allow a significant increase in platinum dose-intensity delivery.

Nasopharyngeal cancer (NPC) is quite rare throughout Europe, accounting for an annual incidence rate below 1 per 100.000, whereas the highest risk area is South East Asia. A predominant occurrence in males is to be noted. NPC is an etiologically multifactorial disease, most probably involving viral, genetic and environmental factors. Carcinomas of the nasopharynx can be divided into two major histotypes: keratinizing squamous cell carcinomas (WHO-type 1) and non-keratinizing carcinomas (WHO-type 2). The histological type is a prognostic factor and it has a clear impact on the outcome of treatment. Standard therapeutic option for early stages of NPC is radiation, while an integration of radiation therapy and chemotherapy is indicated in more advanced stages.

Combination of chemotherapy and surgical resection of metastases is the most promising strategy to improve the fraction of long-term survivors and cured patients in metastatic colorectal cancer. We reproducibly observed evidence of exacerbation of the oxaliplatin-induced neurosensory toxicity following surgery. Total, protein-bound and intra-erythrocytic concentrations of oxaliplatin were measured, whenever possible, immediately prior to surgery and 4, 24 and 48 h following surgical resection. Among 12 patients, seven (58%) patients reported immediate post-operative aggravation of the pre-existing neurotoxicity. At the time of surgery, we detected high intra-erythrocytic platinum concentrations in all patients (median: 1365 µg/l, range: 820–2968 µg/l). While ultrafilterable oxaliplatin was not detectable prior to surgery, it could be detected immediately after surgery and during 48 h. These results suggest that patients heavily pretreated with oxaliplatin may experience aggravation of neurotoxicity after surgery, probably through a redistribution of the pool of intra-erythrocytic oxaliplatin biotransformation products into the plasma. This clinical observation might be the consequence of peroperative hemolysis.

The influence of oxaliplatin (OXA) on 5-fluorouracil (5-FU) plasma clearance was investigated. Patients and methods: A group of 29 patients with advanced colorectal cancer refractory to prior weekly 8-h 5-FU infusion plus bolus folinic acid (FA), received the same combination plus OXA at 130 mg/m2 every 3 weeks, OXA plus 5-FU plus FA on day 1, and 5-FU plus FA on days 8 and 15. Steady-state 5-FU concentrations in plasma were measured weekly and 5-FU clearance was calculated. Both before and after the addition of OXA, the 5-FU dose was individually adjusted according to the pharmacokinetic follow-up (target steady-state plasma concentrations 2.5–3 mg/l). Results and discussion: A total of 122 OXA-containing infusions and 338 5-FU plus FA infusions were given and the median number of infusions per patient was 4 (2–9) and 10 (5–28), respectively. 5-FU plasma clearance was significantly decreased on days 8 and 15 when compared with the value on day 1 and with the values before OXA introduction using a direct paired comparison (2.36 and 2.31 l/min, respectively, vs 3.12 and 3.05 l/min; P