Histone Deacetylase Inhibitor ITF2357 Research Articles

Correction to: Histone deacetylase inhibitor ITF2357 (givinostat) reverts transformed phenotype and counteracts stemness in in vitro and in vivo models of human glioblastoma.

In the original publication, the 6th author's first name and the last name was inverted and incorrectly published. The correct author name is Letizia Ferella.

Histone deacetylase inhibitor ITF2357 (givinostat) reverts transformed phenotype and counteracts stemness in in vitro and in vivo models of human glioblastoma.

Aberrant expression and activity of histone deacetylases (HDACs) sustain glioblastoma (GBM) onset and progression, and, therefore, HDAC inhibitors (HDACi) represent a promising class of anti-tumor agents. Here, we analyzed the effects of ITF2357 (givinostat), a pan-HDACi, in GBM models for its anti-neoplastic potential. A set of GBM- and patient-derived GBM stem-cell lines was used and the ITF2357 effects on GBM oncophenotype were investigated in in vitro and in vivo xenograft models. ITF2357 inhibited HDAC activity and affected GBM cellular fate in a dose-dependent manner by inducing G1/S growth arrest (1-2.5µM) or caspase-mediated cell death (≥ 2.5µM). Chronic treatment with low doses (≤ 1µM) induced autophagy-mediated cell death, neuronal-like phenotype, and the expression of differentiation markers, such as glial fibrillar actin protein (GFAP) and neuron-specific class III beta-tubulin (Tuj-1); this reduces neurosphere formation from patient-derived GBM stem cells. Autophagy inhibition counteracted the ITF2357-induced expression of differentiation markers in p53-expressing GBM cells. Finally, in in vivo experiments, ITF2357 efficiently passed the blood-brain barrier, so rapidly reaching high concentration in the brain tissues, and significantly affected U87MG and U251MG growth in orthotopic xenotransplanted mice. The present findings provide evidence of the key role played by HDACs in sustaining transformed and stem phenotype of GBM and strongly suggest that ITF2357 may have a clinical potential for the HDACi-based therapeutic strategies against GBM.

Control of cytokine mRNA degradation by the histone deacetylase inhibitor ITF2357 in rheumatoid arthritis fibroblast-like synoviocytes: beyond transcriptional regulation

BackgroundHistone deacetylase inhibitors (HDACi) suppress cytokine production in immune and stromal cells of patients with rheumatoid arthritis (RA). Here, we investigated the effects of the HDACi givinostat (ITF2357) on the transcriptional and post-transcriptional regulation of inflammatory markers in RA fibroblast-like synoviocytes (FLS).MethodsThe effects of ITF2357 on the expression and messenger RNA (mRNA) stability of IL-1β-inducible genes in FLS were analyzed using array-based qPCR and Luminex. The expression of primary and mature cytokine transcripts, the mRNA levels of tristetraprolin (TTP, or ZFP36) and other AU-rich element binding proteins (ARE-BP) and the cytokine profile of fibroblasts derived from ZFP36+/+ and ZFP36−/− mice was measured by qPCR. ARE-BP silencing was performed by small interfering RNA (siRNA)-mediated knockdown, and TTP post-translational modifications were analyzed by immunoblotting.ResultsITF2357 reduced the expression of 85% of the analyzed IL-1β-inducible transcripts, including cytokines (IL6, IL8), chemokines (CXCL2, CXCL5, CXCL6, CXCL10), matrix-degrading enzymes (MMP1, ADAMTS1) and other inflammatory mediators. Analyses of mRNA stability demonstrated that ITF2357 accelerates IL6, IL8, PTGS2 and CXCL2 mRNA degradation, a phenomenon associated with the enhanced transcription of TTP, but not other ARE-BP, and the altered post-translational status of TTP protein. TTP knockdown potentiated cytokine production in RA FLS and murine fibroblasts, which in the latter case was insensitive to inhibition by ITF2357 treatment.ConclusionsOur study identifies that regulation of cytokine mRNA stability is a predominant mechanism underlying ITF2357 anti-inflammatory properties, occurring via regulation of TTP. These results highlight the therapeutic potential of ITF2357 in the treatment of RA.

Abstract 3699: Histone deacetylase inhibitor ITF2357 induces apoptosis and increases doxorubicin cytotoxicity in preclinical models of human sarcoma

Abstract Sarcomas are rare malignancies with generally poor prognosis, for which current therapies have shown limited efficacy. In order to improve the prognosis of patients, there is an urgent medical need to identify new molecular targets that can be exploited for the development of innovative treatment approaches. Inhibition of histone deacetylases (HDACs) has emerged as a potential strategy to reverse aberrant epigenetic changes associated with cancer, and HDAC inhibitors (HDACi) have been reported as potent and specific anticancer molecules in preclinical and clinical studies. Here we investigated the molecular and functional effects of a new generation HDACi, ITF2357, in preclinical models of soft tissue and bone sarcomas. A wide panel of sarcomas cells, both established and patient derived cell lines, were used. For in vitro experiments Western Blot, RT-PCR, flow cytometry and conservative isobologram analysis have been performed. In vivo efficacy of ITF2357/doxorubucin combination was evaluated in nude mice bearing sarcoma xenografts. Using in vitro and in vivo sarcoma models, we demonstrate that ITF2357 decreases cell viability, activates apoptosis and increases the growth inhibitory efficacy of doxorubicin. The molecular mechanisms of action of ITF2357-mediated cell death implied the activation of mitochondrial apoptosis, as attested by the increase of pro-apoptotic BH3-only proteins, and both caspase and bcl-2 dependent cell death. We also found that ITF2357 transcriptionally upregulated the pro-apoptotic BH3-only genes Bax, Puma, Noxa and BIM in cells harbouring mutant or wild type p53, thus indicating a p53 independent mechanism. Both bcl-2 overexpression and caspases inhibition strongly reduced apoptosis, corroborating the evidence that activation of mitochondrial pathway occurs upstream and before caspases activation. We also found that ITF2357 induces a canonical autophagic process, and that inhibition of autophagy increased apoptosis induced by ITF2357, indicating that in our models autophagy shows a prosurvival effect. We also reported that ITF2357 induced FOXO1/3a up-regulation, FOXO proteins nuclear accumulation, and transcriptional activation of FOXO-target genes, such as BH3-only proteins Puma, Noxa and Bim. Knockdown experiments demonstrated that reduction of both FOXO1 and 3a did not inhibit the induction of Bim expression in response to ITF2357, and consequently did not protect sarcoma cells against ITF2357-induced apoptosis, independently from p53 status. Notably, ITF2357 synergized with doxorubicin to induce in vitro cell death and to reduce in vivo tumor growth. Therefore ITF2357 may represent an important therapeutic agent against human sarcoma regardless p53 status, and the pharmacological combination of ITF2357 with doxorubicin has the potential to enhance sensitization in different preclinical models of sarcoma. Citation Format: Maria Grazia Tupone, Marta Di Martile, Marianna Desideri, Simonetta Buglioni, Barbara Antoniani, Carlotta Mastroiorio, Rita Falcioni, Virginia Ferraresi, Nicola Baldini, Roberto Biagini, Michele Milella, Daniela Trisciuoglio, Donatella Del Bufalo. Histone deacetylase inhibitor ITF2357 induces apoptosis and increases doxorubicin cytotoxicity in preclinical models of human sarcoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 3699.

Histone deacetylase activity governs diastolic dysfunction through a nongenomic mechanism.

There are no approved drugs for the treatment of heart failure with preserved ejection fraction (HFpEF), which is characterized by left ventricular (LV) diastolic dysfunction. We demonstrate that ITF2357 (givinostat), a clinical-stage inhibitor of histone deacetylase (HDAC) catalytic activity, is efficacious in two distinct murine models of diastolic dysfunction with preserved EF. ITF2357 blocked LV diastolic dysfunction due to hypertension in Dahl salt-sensitive (DSS) rats and suppressed aging-induced diastolic dysfunction in normotensive mice. HDAC inhibitor-mediated efficacy was not due to lowering blood pressure or inhibiting cellular and molecular events commonly associated with diastolic dysfunction, including cardiac fibrosis, cardiac hypertrophy, or changes in cardiac titin and myosin isoform expression. Instead, ex vivo studies revealed impairment of cardiac myofibril relaxation as a previously unrecognized, myocyte-autonomous mechanism for diastolic dysfunction, which can be ameliorated by HDAC inhibition. Translating these findings to humans, cardiac myofibrils from patients with diastolic dysfunction and preserved EF also exhibited compromised relaxation. These data suggest that agents such as HDAC inhibitors, which potentiate cardiac myofibril relaxation, hold promise for the treatment of HFpEF in humans.

Histone deacetylase inhibitor ITF2357 leads to apoptosis and enhances doxorubicin cytotoxicity in preclinical models of human sarcoma

Sarcomas are rare tumors with generally poor prognosis, for which current therapies have shown limited efficacy. Histone deacetylase inhibitors (HDACi) are emerging anti-tumor agents; however, little is known about their effect in sarcomas. By using established and patient-derived sarcoma cells with different subtypes, we showed that the pan-HDACi, ITF2357, potently inhibited in vitro survival in a p53-independent manner. ITF2357-mediated cell death implied the activation of mitochondrial apoptosis, as attested by induction of pro-apoptotic BH3-only proteins and a caspases-dependent mechanism. ITF2357 also induced autophagy, which protected sarcoma cells from apoptotic cell death. ITF2357 activated forkhead box (FOXO) 1 and 3a transcription factors and their downstream target genes, however, silencing of both FOXO1 and 3a did not protect sarcoma cells against ITF2357-induced apoptosis and upregulated FOXO4 and 6. Notably, ITF2357 synergized with Doxorubicin to induce cell death of established and patient-derived sarcoma cells. Furthermore, combination treatment strongly impaired xenograft tumor growth in vivo, when compared to single treatments, suggesting that combination of ITF2357 with Doxorubicin has the potential to enhance sensitization in different preclinical models of sarcoma. Overall, our study highlights the therapeutic potential of ITF2357, alone or in rational combination therapies, for bone and soft tissue sarcomas management.

Implication of the intestinal microbiome as a potential surrogate marker of immune responsiveness to experimental therapies in autoimmune diabetes.

Type 1 diabetes (T1D) is an autoimmune proinflammatory disease with no effective intervention. A major obstacle in developing new immunotherapies for T1D is the lack of means for monitoring immune responsiveness to experimental therapies. The LEW1.WR1 rat develops autoimmunity following infection with the parvovirus Kilham rat virus (KRV) via mechanisms linked with activation of proinflammatory pathways and alterations in the gut bacterial composition. We used this animal to test the hypothesis that intervention with agents that block innate immunity and diabetes is associated with a shift in the gut microbiota. We observed that infection with KRV results in the induction of proinflammatory gene activation in both the spleen and pancreatic lymph nodes. Furthermore, administering animals the histone deacetylase inhibitor ITF-2357 and IL-1 receptor antagonist (Anakinra) induced differential STAT-1 and the p40 unit of IL-12/IL-23 gene expression. Sequencing of bacterial 16S rRNA genes demonstrated that both ITF-2357 and Anakinra alter microbial diversity. ITF-2357 and Anakinra modulated the abundance of 23 and 8 bacterial taxa in KRV-infected animals, respectively, of which 5 overlapped between the two agents. Lastly, principal component analysis implied that ITF-2357 and Anakinra induce distinct gut microbiomes compared with those from untreated animals or rats provided KRV only. Together, the data suggest that ITF-2357 and Anakinra differentially influence the innate immune system and the intestinal microbiota and highlight the potential use of the gut microbiome as a surrogate means of assessing anti-inflammatory immune effects in type 1 diabetes.

Histone deacetylase inhibitor suppresses virus-induced proinflammatory responses and type 1 diabetes

Microbial infections are hypothesized to play a key role in the mechanism leading to type 1 diabetes (T1D). We used the LEW1.WR1 rat model of Kilham rat virus (KRV)-induced islet destruction to better understand how virus infection triggers T1D. Inoculation of the LEW1.WR1 rat with KRV results in systemic inflammation followed by insulitis and islet destruction 2-4 weeks post-infection. In this study, we evaluated the effect of treatment with the anti-inflammatory histone deacetylase inhibitor (HDACi) ITF-2357 on KRV-induced immunity and disease progression. Administering LEW1.WR1 rats with KRV plus ITF-2357 on 14 consecutive days beginning on the day of infection protected animals from islet infiltration and T1D. ITF-2357 reversed KRV-induced T and B cell accumulation in the spleen or pancreatic lymph nodes on day 5 following infection. Moreover, ITF-2357 reduced the expression level of KRV-induced p40 subunit of IL-12/IL-23 in spleen cells in vitro and in the peripheral blood in vivo. ITF-2357 suppressed the KRV-induced expression of transcripts for IRF-7 in the rat INS-1 beta cell line. ITF-2357 increased the virus-induced IL-6 gene expression in the spleen, but did not alter the ability of LEW1.WR1 rats to develop normal KRV-specific humoral and cellular immune responses and clear the virus from the pancreatic lymph nodes, spleen, and serum. Finally, ITF-2357 reversed virus-induced modulation of bacterial communities in the intestine early following infection. The data suggest that targeting innate immune pathways with inhibitors of HDAC might represent an efficient therapeutic strategy for preventing T1D. Microbial infections have been implicated in triggering type 1 diabetes in humans and animal models. The LEW1.WR1 rat develops inflammation and T1D following infection with Kilham rat virus. The histone deacetylase inhibitor ITF-2357 suppresses virus-induced inflammation and prevents diabetes. ITF-2357 prevents T1D without altering virus-specific adaptive immunity or virus clearance. ITF-2357 therapy may be an efficient approach to prevent T1D in genetically susceptible individuals.

The HDAC inhibitor Givinostat modulates the hematopoietic transcription factors NFE2 and C-MYB in JAK2V617F myeloproliferative neoplasm cells

We investigated the mechanism of action of the histone deacetylase inhibitor Givinostat (GVS) in Janus kinase 2 (JAK2)(V617F) myeloproliferative neoplasm (MPN) cells. GVS inhibited colony formation and proliferation and induced apoptosis at doses two- to threefold lower in a panel of JAK2(V617F) MPN compared to JAK2 wild-type myeloid leukemia cell lines. By global gene expression analysis, we observed that at 6 hours, GVS modulated 293 common genes in the JAK2(V617F) cell lines HEL and UKE1, of which 19 are implicated in cell cycle regulation and 33 in hematopoiesis. In particular, the hematopoietic transcription factors NFE2 and C-MYB were downmodulated by the drug specifically in JAK2(V617F) cells at both the RNA and protein level. GVS also inhibited JAK2-signal transducer and activator of transcription 5-extracellular signal-regulated kinase 1/2 phosphorylation, but modulation of NFE2 and C-MYB was JAK2-independent, as shown using the JAK2 inhibitor TG101209. GVS had a direct effect on the NFE2 promoters, as demonstrated by specific enrichment of associated histone H3 acetylated at lysine 9. Modulation by GVS of NFE2 was also observed in freshly isolated CD34(+) cells from MPN patients, and was accompanied by inhibition of their proliferation and differentiation toward the erythroid lineage. We conclude that GVS acts on MPN cells through dual JAK2-signal transducer and activator of transcription 5-extracellular signal-regulated kinase 1/2 inhibition and downmodulation of NFE2 and C-MYB transcription.

Pharmacokinetics, Safety and Inducible Cytokine Responses during a Phase 1 Trial of the Oral Histone Deacetylase Inhibitor ITF2357 (Givinostat)

ITF2357 (givinostat) is a histone deacetylase inhibitor with antiinflammatory properties at low nanomolar concentrations. We report here a phase I safety and pharmacokinetics trial in healthy males administered 50, 100, 200, 400 or 600 mg orally. After 50 mg, mean maximal plasma concentrations reached 104 nmol/L 2 h after dosing, with a half-life of 6.9 h. After 100 mg, maximal concentration reached 199 nmol/L at 2.1 h with a half-life of 6.0 h. Repeat doses for 7 consecutive days of 50, 100 or 200 mg resulted in nearly the same kinetics. There were no serious adverse effects (AEs) and no organ toxicities. However, there was a dose-dependent but transient fall in platelets. After 7 daily doses of 50 or 100 mg, the mean decrease in platelets of 17 and 25% was not statistically significant and returned to baseline within 14 d. Blood removed from the subjects after oral dosing was cultured ex vivo with endotoxin, and the release of tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-6, IL-1Ra, interferon (IFN)-γ and IL-10 was determined. Maximal reduction in IL-1β, TNFα, IL-6 and IFNγ was observed 4 h after dosing but returned to baseline at 12 h. There was no significant reduction in IL-1Ra or IL-10. With daily dosing, the fall in cytokine production in blood cultures observed on day 7 was nearly the same as that of the first day. We conclude that dosing of 50 or 100 mg ITF2357 is safe in healthy humans and transiently but repeatedly reduces the production of proinflammatory cytokines without affecting production of antiinflammatory cytokines.

Effects of the Histone Deacetylase Inhibitor ITF2357 in Autoinflammatory Syndromes

We explored the effects of the oral histone deacetylase (HDAC) inhibitor ITF2357 in patients with autoinflammatory syndrome. In this prospective open-label pilot study, eight patients were enrolled; one patient with tumor necrosis factor receptor-associated periodic syndrome (TRAPS), three patients with hyper-IgD and periodic fever syndrome (HIDS) and four patients with Schnitzler syndrome were closely followed during 90 d of ITF2357 treatment. Three patients with Schnitzler syndrome and one TRAPS patient experienced a partial remission. In four patients, there was no effect. In HIDS patients, there was a tendency toward a higher attack frequency and increasing attack severity. In two patients (one TRAPS and one HIDS), we observed a decrease of acute-phase response without signs of clinical improvement. One patient with Schnitzler syndrome showed a partial response despite an ongoing acute-phase response. In conclusion, ITF2357 monotherapy was able to induce partial response only in patients with Schnitzler syndrome and no response in patients with HIDS.

The Oral Histone Deacetylase Inhibitor ITF2357 Reduces Cytokines and Protects Islet β Cells In Vivo and In Vitro

In type 1 diabetes, inflammatory and immunocompetent cells enter the islet and produce proinflammatory cytokines such as interleukin-1β (IL-1β), IL-12, tumor necrosis factor-α (TNFα) and interferon-γ (IFNγ); each contribute to β-cell destruction, mediated in part by nitric oxide. Inhibitors of histone deacetylases (HDAC) are used commonly in humans but also possess antiinflammatory and cytokine-suppressing properties. Here we show that oral administration of the HDAC inhibitor ITF2357 to mice normalized streptozotocin (STZ)-induced hyperglycemia at the clinically relevant doses of 1.25-2.5 mg/kg. Serum nitrite levels returned to nondiabetic values, islet function improved and glucose clearance increased from 14% (STZ) to 50% (STZ + ITF2357). In vitro, at 25 and 250 nmol/L, ITF2357 increased islet cell viability, enhanced insulin secretion, inhibited MIP-1α and MIP-2 release, reduced nitric oxide production and decreased apoptosis rates from 14.3% (vehicle) to 2.6% (ITF2357). Inducible nitric oxide synthase (iNOS) levels decreased in association with reduced islet-derived nitrite levels. In peritoneal macrophages and splenocytes, ITF2357 inhibited the production of nitrite, as well as that of TNFα and IFNγ at an IC(50) of 25-50 nmol/L. In the insulin-producing INS cells challenged with the combination of IL-1β plus IFNγ, apoptosis was reduced by 50% (P < 0.01). Thus at clinically relevant doses, the orally active HDAC inhibitor ITF2357 favors β-cell survival during inflammatory conditions.

The Histone Deacetylase Inhibitor ITF2357 Decreases Surface CXCR4 and CCR5 Expression on CD4+ T-Cells and Monocytes and is Superior to Valproic Acid for Latent HIV-1 Expression in Vitro

Chromatin-associated repression is one mechanism that maintains HIV-1 latency. Inhibition of histone deacetylases (HDAC) reverses this repression resulting in viral expression from quiescently infected cells. Clinical studies with the HDAC inhibitor valproic acid (VPA) failed to substantially decrease the latent pool within resting CD4(+) cells. Here we compared the efficacy of ITF2357, an orally active and safe HDAC inhibitor, with VPA for HIV-1 expression from latently infected cells in vitro. We also evaluated the effect of ITF2357 on the surface expression of CXCR4 and CCR5. Latently infected cell lines were incubated with either ITF2357 or VPA and p24 levels were measured. Peripheral blood mononuclear cells of uninfected donors were treated with ITF2357 and HIV-1 coreceptors expression was assessed by flow cytometry. At clinically relevant concentrations, ITF2357 increased p24 by 15-fold in ACH2 cells and by 9-fold in U1 cells, whereas VPA increased expression less than 2-fold. Analogues of ITF2357 primarily targeting HDAC-1 increased p24 up to 30-fold. In CD4(+) T cells treated with ITF2357, CXCR4 expression decreased by 54% (P < 0.001). ITF2357 is superior to VPA in inducing HIV-1 from latently infected cells. Safely used in humans, ITF2357 is an attractive candidate for HIV-1 clinical purging.

The histone deacetylase inhibitor ITF2357 decreases surface CXCR4 and CCR5 expression in CD4+ T-cells and monocytes and induces latent HIV-1 expression in vitro

The histone deacetylase inhibitor ITF2357 decreases surface CXCR4 and CCR5 expression in CD4+ T-cells and monocytes and induces latent HIV-1 expression in vitro

Decreased whole blood cytokine production during a phase I trial of the histone deacetylase inhibitor ITF2357

Decreased whole blood cytokine production during a phase I trial of the histone deacetylase inhibitor ITF2357

The oral histone deacetylase inhibitor ITF2357 reduces cytokine production, cytokine activities and protects islet β-cells in vivo and in vitro

The oral histone deacetylase inhibitor ITF2357 reduces cytokine production, cytokine activities and protects islet β-cells in vivo and in vitro

Histone deacetylase inhibitor ITF2357 is neuroprotective, improves functional recovery, and induces glial apoptosis following experimental traumatic brain injury

Despite efforts aimed at developing novel therapeutics for traumatic brain injury (TBI), no specific pharmacological agent is currently clinically available. Here, we show that the pan-histone deacetylase (HDAC) inhibitor ITF2357, a compound shown to be safe and effective in humans, improves functional recovery and attenuates tissue damage when administered as late as 24 h postinjury. Using a well-characterized, clinically relevant mouse model of closed head injury (CHI), we demonstrate that a single dose of ITF2357 administered 24 h postinjury improves neurobehavioral recovery from d 6 up to 14 d postinjury (improved neurological score vs. vehicle; P< or =0.05), and that this functional benefit is accompanied by decreased neuronal degeneration, reduced lesion volume (22% reduction vs. vehicle; P< or =0.01), and is preceded by increased acetylated histone H3 levels and attenuation of injury-induced decreases in cytoprotective heat-shock protein 70 kDa and phosphorylated Akt. Moreover, reduced glial accumulation and activation were observed 3 d postinjury, and total p53 levels at the area of injury and caspase-3 immunoreactivity within microglia/macrophages at the trauma area were elevated, suggesting enhanced clearance of these cells via apoptosis following treatment. Hence, our findings underscore the relevance of HDAC inhibitors for ameliorating trauma-induced functional deficits and warrant consideration of applying ITF2357 for this indication.

Pleiotropic anti-myeloma activity of ITF2357: inhibition of interleukin-6 receptor signaling and repression of miR-19a and miR-19b

The histone deacetylase inhibitor ITF2357 has potent cytotoxic activity in multiple myeloma in vitro and has entered clinical trials for this disease. In order to gain an overall view of the activity of ITF2357 and identify specific pathways that may be modulated by the drug, we performed gene expression profiling of the KMS18 multiple myeloma cell line treated with the drug. The modulation of several genes and their biological consequence were verified in a panel of multiple myeloma cell lines and cells freshly isolated from patients by using polymerase chain reaction analysis and western blotting. Out of 38,500 human genes, we identified 140 and 574 up-regulated genes and 102 and 556 down-modulated genes at 2 and 6 h, respectively, with a significant presence of genes related to transcription regulation at 2 h and to cell cycling and apoptosis at 6 h. Several of the identified genes are particularly relevant to the biology of multiple myeloma and it was confirmed that ITF2357 also modulated their encoded proteins in different multiple myeloma cell lines. In particular, ITF2357 down-modulated the interleukin-6 receptor alpha (CD126) transcript and protein in both cell lines and freshly isolated patients' cells, whereas it did not significantly modify interleukin-6 receptor beta (CD130) expression. The decrease in CD126 expression was accompanied by decreased signaling by interleukin-6 receptor, as measured by STAT3 phosphorylation in the presence and absence of inter-leukin-6. Finally, the drug significantly down-modulated the MIRHG1 transcript and its associated microRNA, miR-19a and miR-19b, known to have oncogenic activity in multiple myeloma. ITF2357 inhibits several signaling pathways involved in myeloma cell growth and survival.

A phase II multiple dose clinical trial of histone deacetylase inhibitor ITF2357 in patients with relapsed or progressive multiple myeloma

ITF2357, an orally effective member of the family of histone deacetylase inhibitors, is a potent inducer of apoptosis and death of multiple myeloma (MM) cells. We performed a phase-II, multiple-dose clinical trial in 19 patients with relapsed or progressive MM to determine the maximum tolerated dose (MTD) of ITF2357 administered twice daily for four consecutive days every week for 4 weeks (i.e., first cycle). The first six patients received 150 mg ITF2357 twice daily. Since two of them experienced a dose-limiting toxicity (DLT) during the first cycle, the subsequent patients received 100 mg ITF2357 twice daily. This was the MTD, as only one DLT occurred. Up to 12 weeks (i.e., three cycles) of treatment were scheduled. Oral dexamethasone was allowed to a maximum weekly amount of 20 mg. Median duration of treatment was 6 weeks, ranging from two (two patients) to 12 weeks (five patients). Four patients suffered from serious adverse events. Three patients experienced grade 3-4 gastro-intestinal toxicity and three had transient electrocardiographic abnormalities. Thrombocytopenia occurred in all but one patient (grade 3-4 in ten patients). At last follow-up, five patients were in stable disease, five had disease progression, and nine had died all of progressive MM. In conclusion, when given at a dose of 100 mg twice daily alone or combined with dexamethasone, ITF2357 proved tolerable but showed a modest clinical benefit in advanced MM.

Phase II Trial of Combination of the Histone Deacetylase Inhibitor ITF2357 and Meclorethamine Demonstrates Clinical Activity and Safety in Heavily Pretreated Patients with Relapsed/Refractory Hodgkin Lymphoma (HL)

Introduction: HL patients with refractory disease or relapsing after autologous stem cell transplantation (SCT) have very poor prognosis with currently available salvage chemotherapy. ITF2357 (Italfarmaco S.p.A., Milano, Italy) is an orally bioavailable hydroxamate inhibitor of class I and II histone deacetylases (HDACs) with preclinical and clinical activity as single agent in hematopoietic cancers. Our preclinical data demonstrating a synergistic activity of ITF2357 with the alkylating agent Meclorethamine in HL cell lines, established the rationale for this currently ongoing phase II study aimed to determine activity and safety of the sequential ITF2357 and Meclorethamine treatment.Methods: Patients with relapsed/refractory HL who have failed second- or subsequent-line salvage chemo-radiotherapy were enrolled. Eligibility criteria included prior treatment with autologous and/or allogeneic SCT, prior treatment with single agent Meclorethamine, at least one target lesion ≥2 cm, ECOG performance status of 0–1, and platelet ≥75,000/μL. ITF2357 (50 mg QID, per os, days 1–3) followed by Meclorethamine (6 mg/sqm, intravenously, day 4) was dosed in 3-week cycles until disease progression or appearance of clinical significant toxicity, but for a maximum of 12 cycles. Tumor responses were determined after cycles 2, 6, 9 and 12 by computed tomography (CT) and positron emission tomography (PET) scan. Serum levels of thymus- and activation-regulated chemokine (TARC) were assessed by ELISA prior to each cycle of therapy.Results: To date, 19 patients have been enrolled (16 males and 3 females; median age, 33 years; range, 21–61 years), including 8 patients enrolled in a preliminary compassionate use trial, and 11 patients of a planned 23 enrolled in this ongoing phase II trial. Prior to study entry, patients received a median of 5 (range 2–7) lines of treatment with autologous SCT performed in 15 (79%) and an additional allogeneic SCT in 5 (26%) patients. At study entry, 6 patients had relapsed and 13 refractory HL. Seventeen of 19 patients received a median of 3 cycles (range, 1–10) of ITF2357/Meclorethamine and are evaluable for response by CT and PET scans. Best response to therapy included 2 (12%) complete remissions (CR) and 3 (18%) partial remissions (PR), for an overall response rate (ORR) of 30%. In addition, 5 (29%) patients had stable disease (SD) with 4 (23%) patients achieving SD for ≥4 months, while 7 (41%) patients progressed. After the first cycle of therapy, serum TARC levels were decreased by 70±16% (mean±SEM, P ≤0.05) in 5 patients who achieved major clinical responses (PR+CR), and by 16±14% (P = ns) in patients who achieved SD. Overall, therapy was well tolerated without significant adverse events, and no patient required dose reductions for management of toxicities. The most common drug-related non-hematological toxicities were grade 1–2 nausea (12/17) and fatigue (14/17). Four patients experienced infections [pneumonia (n = 1), oral herpes simplex (n = 2), oral candidiasis (n = 1)]. No prolongation of QT/QTc interval has been detected over 70 therapy cycles. Hematological toxicities included grade 1–2 anemia (13/17), neutropenia (7/17), and thrombocytopenia (12/17). Grade 3–4 neutropenia and thrombocytopenia were observed in 7 and 8 patients, respectively. RBC and platelet transfusions were required by 4 and 5 patients, respectively.Conclusions: Preliminary results from this ongoing trial suggest that ITF2357, in combination with Meclorethamine, demonstrates significant anti-tumor activity in heavily pretreated relapsed/refractory HL and is well tolerated. Preliminary data also suggest that early decrease in serum TARC levels may predict response to therapy.