Can-Fite BioPharma (Israel)

Established treatments for advanced hepatocellular carcinoma (HCC) with Child-Pugh cirrhosis B (CPB, moderate hepatic dysfunction) are lacking. A recently published randomized phase 2 study in CPB HCC investigating the safety and efficacy of namodenoson (25 mg BID), an A3 adenosine-receptor agonist vs. placebo, suggested a favorable safety profile and a positive efficacy signal in patients with HCC with a CPB score of 7 (CPB7). The present study reports a 61-year-old woman with CPB7 HCC who received namodenoson for over 6 years through this study and its open-label extension. Computed tomography scans demonstrated partial and complete responses after 7 weeks and 4 years of treatment, respectively. Low albumin levels (31 g/l) and elevated baseline levels of alanine transaminase and aspartate aminotransferase (68 U/l and 44 U/l, respectively) were reported. After 4 weeks of treatment, these levels normalized and were stable for over 6 years. No treatment-emergent adverse events were noted. At the time of reporting, the response is ongoing as manifested by imaging studies and liver function evaluation.

Abstract Background: The Wnt/β-catenin pathway controls the growth of pancreatic carcinoma by regulating processes such as cell cycle progression, apoptosis, and the tumor immune microenvironment. Treating pancreatic cancer with Wnt pathway inhibitors was found to be toxic in clinical studies. Namodenoson, an A3 adenosine receptor (A3AR) agonist, is under clinical development as a treatment of advanced liver cancer, where namodenoson was shown to have an excellent safety profile in phase II studies and is a phase III study is ongoing. The mechanism of action of namodenoson involves de-regulation of the Wnt and NF-κB signaling pathways, followed by an increase in pro-apoptotic proteins and Fas-ligand, resulting in tumor growth inhibition. The objectives of the currents study were to examine the anti-growth effect of namodenoson on pancreatic carcinoma cells both in vitro and in vivo and to investigate the molecular mechanisms involved. Methods: BxPC-3 human pancreatic carcinoma cells were cultured in the presence and absence of 0.01, 0.1, and 1 nM namodenoson, or in the presence of a combination of namodenoson (0.1 nM) and gemcitabine (0.2 µM). Cell growth was monitored via 3[H]-thymidine proliferation, MTT, and PrestoBlue assays. Western blot analyses were conducted to identify the regulatory cell growth proteins impacted by the treatment. A xenograft model with human BxPC-3 cells in nude mice was established to investigate the in-vivo effect of namodenoson. Results: A significant dose-dependent growth inhibition of BxPC-3 cells was observed with namodenoson in the3[H]-thymidine proliferation assay (1 nM: 67.4% ± 1.7%, p < 0.001; 0.1 nM: 53.7% ± 6.3%, p< 0.05; 0.01 nM: 27.9 % ± 2.3%, p< 0.005). The combination of namodenoson and gemcitabine showed an additive inhibitory effect in the MTT assay (namodenoson: 48.6% ± 1.4%; gemcitabine: 44.4% ± 0.7%; namodenoson plus gemcitabine: 65.4% ± 1.4%; p<0.001 for all). Western blot analyses demonstrated that namodenoson treatment was associated with de-regulation of the Wnt pathway regulatory proteins including p-Akt, NF- κB, GSK-3β, β-catenin and up-regulation of the BAD and BAX apoptotic proteins. In the xenograft model, daily oral treatment with 10 µg/kg of namodenoson led to a significant progressive inhibition of tumor growth. Conclusions: Nanomolar concentrations of namodenoson inhibited the growth of pancreatic carcinoma in cell culture and in a xenograft model. This effect involved A3AR activation and de-regulation of the Wnt/β-catenin pathway. Our results support a potential clinical utility for namodenoson in pancreatic cancer, a disease where an unmet clinical need exists, and novel therapeutic opportunities are required. Citation Format: Pnina Fishman, Avital Bareket-Samish, Inbal Izhak. Namodenoson inhibits the growth of pancreatic carcinoma via de-regulation of the Wnt/β-catenin signaling pathway [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Pancreatic Cancer; 2023 Sep 27-30; Boston, Massachusetts. Philadelphia (PA): AACR; Cancer Res 2024;84(2 Suppl):Abstract nr A074.

e15134 Background: Namodenoson, an A3 adenosine receptor (A3AR) agonist, is currently in a phase 3 trial for the treatment of advanced liver cancer. The mechanism of action of namodenoson involves de-regulation of the Wnt and NF-κB signaling pathways, followed by an increase in pro-apoptotic proteins and Fas-ligand, resulting in tumor growth inhibition. As the Wnt signaling pathway is also highly implicated in pancreatic carcinogenesis, we examined the anti-growth effect of namodenoson on pancreatic carcinoma cell lines and investigated the molecular mechanism involved. Methods: BxPC-3 human pancreatic carcinoma cells were cultured in the presence and absence of 0.01, 0.1, and 1 nM namodenoson. A combined treatment of namodenoson (0.1 nM) and gemcitabine (0.2 µM) was also studied. 3[H]-thymidine proliferation and MTT assays were used to monitor cell growth, and Western blot analyses were performed to identify the involved regulatory cell growth proteins. Results: Results of the 3[H]-thymidine proliferation assays demonstrated significant dose-dependent inhibition of the growth of BxPC-3 cells with namodenoson (1 nM: 67.4% ± 1.7%, p < 0.001; 0.1 nM: 53.7% ± 6.3%, p < 0.05; 0.01 nM: 27.9 % ± 2.3%, p < 0.005). The MTT results revealed that a combined treatment with namodenoson plus gemcitabine had an additive inhibitory effect (namodenoson: 48.6% ± 1.4%; gemcitabine: 44.4% ± 0.7%; namodenoson plus gemcitabine: 65.4% ± 1.4%; p < 0.001 for all). Western blot analyses showed that namodenoson treatment was associated with downregulation of the Wnt pathway regulatory proteins including p-Akt, NF- κB, GSK-3β, and β-catenin. Conclusions: Our findings showed that nanomolar concentrations of namodenoson inhibit the growth of pancreatic carcinoma via A3AR activation and de-regulation of the Wnt/β-catenin pathway, both as a monotherapy and in combination with gemcitabine. Thus, these results support a potential role for namodenoson in treating pancreatic cancer, thereby opening a novel therapeutic opportunity for this disease.

Adenosine plays a major role in erection by binding to its receptors and activating pathways resulting in increased arterial blood flow and intracavernosal pressure (ICP). CF602, an allosteric modulator of the A3 adenosine receptor (A3AR), increases the binding affinity of the endogenous adenosine to the receptor. We examined the effect of CF602 on resolving erectile dysfunction (ED) in a diabetic ED rat model (streptozotocin-induced diabetic rats that were screened for ED using the apomorphine test). ED was assessed by measuring ICP and main arterial pressure (MAP) during electrostimulation of the cavernosal nerve. A single dose of CF602 or placebo was applied either topically (100 μl from a 100 nM or 500 nM solution) or orally (100, 200 or 500 μg/kg) prior to erectile function assessment. A significant dose-dependent improvement in the ICP:MAP ratio without a change in MAP was recorded with the topical and oral CF602 treatments. A significant increase in smooth muscle:collagen ratio, vascular endothelial growth factor and endothelial nitric oxide synthase was also observed in both administration modes. In conclusion, topical and oral treatment with CF602 significantly improved erectile function, supporting its further evaluation as a treatment for ED.

The A3 adenosine receptor (A3AR) is overexpressed in pathological human cells. Piclidenoson and namodenoson are A3AR agonists with high affinity and selectivity to A3AR. Both induce apoptosis of cancer and inflammatory cells via a molecular mechanism entailing deregulation of the Wnt and the NF-κB signaling pathways. Our company conducted phase I studies showing the safety of these 2 molecules. In the phase II studies in psoriasis patients, piclidenoson was safe and demonstrated efficacy manifested in significant improvements in skin lesions. Namodenoson is currently being developed to treat liver cancer, where prolonged overall survival was observed in patients with advanced liver disease and a Child–Pugh B score of 7. A pivotal phase III study in this patient population has been approved by the FDA and the EMA and is currently underway. Namodenoson is also being developed to treat non-alcoholic steatohepatitis (NASH). A Phase IIa study has been successfully concluded and showed that namodenoson has anti-inflammatory, anti-fibrosis, and anti-steatosis effects. A phase IIb study in NASH is currently enrolling patients. In conclusion, A3AR agonists are promising drug candidates in advanced stages of clinical development and demonstrate safety and efficacy in their targeted indications.

LINKED CONTENTThis article is linked to Safadi et al papers. To view these articles, visit https://doi.org/10.1111/apt.16664 and https://doi.org/10.1111/apt.16748

Abstract Background: The A3 Gi protein adenosine receptor (A3AR) is highly expressed in tumor compared to normal cells. A3AR agonists were shown to inhibit the growth of various tumor cell types via down-regulation of the Wnt and NF-κB signaling pathways. CF102 is a highly selective agonist of the A3AR, shown to have an anti-tumor effect in liver cancer in in vivo models. CF102 induced apoptosis via up-regulation of caspase-3 and the mitochondrial proteins Bax and Bad, demonstrating cell death in the tumor cells. In this study we explored the molecular mechanism involved with the effect of CF102 on human hepatocellular carcinoma cells. Methods: CF102 was added to a medium culture of Hep3b for 48 hours. CF102 effect was observed using Lactate dehydrogenase (LDH), MTT and H3 Thymidine proliferation assays. Cell mRNA and protein were extracted and were analyzed for different signaling pathways. Results: CF102 inhibits the proliferation of Hep3b cells and showed an apoptotic activity in MTT assay. A cytotoxicity effect of CF102 was observed when high levels of LDH were measured in the culture medium of CF102 treated cells compared to the control. Moreover, cyclin D1 expression levels were down-regulated and caspase-3 levels were up-regulated upon CF102 treatment. Both mRNA and protein expression levels of A3AR were down-regulated by CF102 with a subsequent decrease in all members of the JAK-STAT signaling pathway including pSTAT-1, p-JAK-2 and p-AKT along with up-regulation of SOCS-1 and SOCS-3. Conclusions: CF102 showed an anti-cancer activity via down-regulation of the A3AR and the JAK-STAT signaling pathway. CF102 induces cytotoxicity effect resulting in apoptosis of Hep3b cells, indicating that this drug may be considered as an anti-cancer drug for the treatment of human hepatocellular carcinoma. Note: This abstract was not presented at the meeting. Citation Format: Shira Cohen, Faina Barer, Salomon M. Stemmer, Pnina Fishman. CF102 induces apoptosis of hepatocellular carcinoma. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 679. doi:10.1158/1538-7445.AM2015-679

We tested a panel of naturally occurring nucleosides for their affinity towards adenosine receptors. Both N6-(2-isopentenyl)adenosine (IPA) and racemic zeatin riboside were shown to be selective human adenosine A3 receptor (hA3R) ligands with affinities in the high nanomolar range (Ki values of 159 and 649 nM, respectively). These values were comparable to the observed Ki value of adenosine on hA3R, which was 847 nM in the same radioligand binding assay. IPA also bound with micromolar affinity to the rat A3R. In a functional assay in Chinese hamster ovary cells transfected with hA3R, IPA and zeatin riboside inhibited forskolin-induced cAMP formation at micromolar potencies. The effect of IPA could be blocked by the A3R antagonist VUF5574. Both IPA and reference A3R agonist 2-chloro-N6-(3-iodobenzyl)adenosine-5′-N-methylcarboxamide (Cl-IB-MECA) have known antitumor effects. We demonstrated strong and highly similar antiproliferative effects of IPA and Cl-IB-MECA on human and rat tumor cell lines LNCaP and N1S1. Importantly, the antiproliferative effect of low concentrations of IPA on LNCaP cells could be fully blocked by the selective A3R antagonist MRS1523. At higher concentrations, IPA appeared to inhibit cell growth by an A3R-independent mechanism, as was previously reported for other A3R agonists. We used HPLC to investigate the presence of endogenous IPA in rat muscle tissue, but we could not detect the compound. In conclusion, the antiproliferative effects of the naturally occurring nucleoside IPA are at least in part mediated by the A3R.Electronic supplementary materialThe online version of this article (doi:10.1007/s11302-011-9244-9) contains supplementary material, which is available to authorized users.

SummaryDuring the drilling process and transport of crude oil, water mixes with the petroleum. At oil terminals, the water settles to the bottom of storage tanks. This drainage water is contaminated with emulsified oil and water‐soluble hydrocarbons and must be treated before it can be released into the environment. In this study, we tested the efficiency of a continuous flow, two‐stage bioreactor for treating drainage water from an Israeli oil terminal. The bioreactor removed all of the ammonia, 93% of the sulfide and converted 90% of the total organic carbon (TOC) into carbon dioxide. SYBR Gold staining indicated that reactor 1 contained 1.7 × 108 bacteria and 3.7 × 108 phages per millilitre, and reactor 2 contained 1.3 × 108 bacteria and 1.7 × 109 phages per millilitre. The unexpectedly high mineralization of TOC and high concentration of phage in reactor 2 support the concept of a phage‐driven microbial loop in the bioremediation of the drainage water. In general, application of this concept in bioremediation of contaminated water has the potential to increase the efficiency of processes.