An Ontario Health (Cancer Care Ontario) Clinical Practice Guideline: Surveillance Strategies in Patients with Stage I, II, III or Resectable IV Melanoma Who Were Treated with Curative Intent

AIMS

To make recommendations on managing the surveillance of patients with stage I, II, III or resectable IV melanoma who are clinically free of disease following treatment with curative intent.

MATERIALS AND METHODS

This guideline was developed by Ontario Health's (Cancer Care Ontario's) Program in Evidence-Based Care and the Melanoma Disease Site Group (including seven medical oncologists, four surgical oncologists, three dermatologists, one radiation oncologist and one patient representative). The MEDLINE, EMBASE, Cochrane Library, PROSPERO databases and the main relevant guideline websites were searched. Internal and external reviews were conducted, with final approval by the Program in Evidence-Based Care and the Melanoma Disease Site Group. The Grading of Recommendations, Assessment, Development and Evaluation approach was followed, and the Modified Delphi method was used.

RESULTS

Based on the current evidence (eight eligible original study papers and four relevant guidelines) and the clinical opinions of the authors of this guideline, the initial recommendations were made. To reach 75% agreement for each recommendation, the Melanoma Disease Site Group (16 members) voted twice and one recommendation was voted on three times. After a comprehensive internal and external review process (including national and international reviewers), 12 recommendations, three weak recommendations and six qualified statements were ultimately made.

CONCLUSIONS

After a systematic review, a comprehensive internal and external review process and a consensus process, the current guideline has been created. The guideline authors believe that this guideline will help clinicians, patients and policymakers make well-informed healthcare decisions that will guide them in clinical melanoma surveillance and ultimately assist in improving patient outcomes.

Inhibition of protein arginine deiminase 4 prevents inflammation-mediated heart failure in arthritis

Rheumatoid arthritis is a prototypic inflammatory condition with affected patients being at greater risk of incident heart failure (HF). Targeting innate immune cell function in the pathogenesis of HF bears the potential to guide the development of future therapies. A collagen-induced arthritis (CIA) model in DBA/1 J mice was used to generate arthritis. Mice with CIA developed concentric hypertrophic myocardial remodeling, left ventricular (LV) diastolic dysfunction, and HF with elevated plasma B-type natriuretic peptide levels but preserved LV ejection fraction. Key features of HF in CIA were increased infiltration of activated neutrophils, deposition of neutrophil extracellular traps in the myocardium, and increased tissue levels of the proinflammatory cytokine IL-1β. Specific inhibition of protein arginine deiminase 4 (PAD4) by an orally available inhibitor (JBI-589), administered after the onset of clinical arthritis, prevented HF with reduced neutrophil infiltration. We identify PAD4-mediated neutrophil activation and recruitment as the key thromboinflammatory pathway driving HF development in arthritis. Targeting PAD4 may be a viable therapeutic approach for the prevention of HF secondary to chronic inflammation.

Mini review: Breast cancer care in individuals with differences of sexual development

Disorders or differences of sexual development encompasses an important group of conditions that affects up to 1 in 5,000 live births. Many individuals living in the female gender includes Turner syndrome, congenital adrenal hyperplasia and conditions with 46XY karyotype such as gonadal dysgenesis (Swyer syndrome). Individuals are commenced on high dose oestrogen to initiate and maintain development of secondary sexual characteristics such as breasts which is paramount in them identifying in the female gender. We highlight the first case of a patient with Swyer syndrome who was treated with long term oestrogen therapy and later developed breast cancer. In individuals with gonadal dysgenesis, testicular malignancy is a recognised risk and is screened for. Prolonged exposure to exogenous and endogenous hormones can increase the risk of breast cancer however how much this risk increases in those taking high dose hormones is not documented in the literature. We aim to highlight the importance of breast cancer treatment and surgical reconstruction in this group and whether they should be considered for early breast cancer screening. CONCLUSION: It is imperative that triple assessment is undertaken in every patient with a breast lump, regardless of gender identification. Clinicians must not delay investigations in this patient group due to a misunderstanding of their condition. Those on long term hormone supplementation should be entered into the breast screening program at an earlier age with Magnetic Resonance Imaging surveillance. Careful consideration of post treatment endocrine therapy is required and under the care of the multi-disciplinary team.

Alleviation of arthritis through prevention of neutrophil extracellular traps by an orally available inhibitor of protein arginine deiminase 4

Protein arginine deiminases (PAD) 4 is an enzyme that catalyzes citrullination of protein and its role in autoimmune diseases has been established through clinical genetics and gene knock out studies in mice. Further, studies with PAD4 - deficient mice have shown that PAD4 deficiency does not lead to increased infection or immune suppression, which makes PAD4 an attractive therapeutic target for auto-immune and inflammatory diseases. PAD4 has critical enzymatic role of promoting chromatin decondensation and neutrophil extracellular traps (NETs) formation that is associated with a number of immune-mediated pathological conditions. Here, we present a non-covalent PAD4 inhibitor JBI-589 with high PAD4 isoform selectivity and delineated its binding mode at 2.88 Å resolution by X-ray crystallography. We confirmed its effectiveness in inhibiting NET formation in vitro. Additionally, by using two mouse arthritis models for human rheumatoid arthritis (RA), the well-known disease associated with PAD4 clinically, we established its efficacy in vivo. These results suggest that JBI-589 would be beneficial for both PAD4 and NET-associated pathological conditions.

Abstract B029: LSD1-HDAC6 dual inhibitor JBI-802 is an epigenetic modulating agent with a novel mechanism of action that target MYC amplification in multiple neuroendocrine tumor types

MYC is considered a master regulator of human cancers by modulating the transcription of numerous cancer-related genes. MYC amplification is reported in about 15% of all human cancers and is generally associated with poor prognosis and resistance to treatments. Focal amplification of MYC together with mutation in RB1 and p53 is an important event in the metastatic process of neuroendocrine tumor development. While limited options are available for direct targeting, transcriptional modulation via epigenetic modulating agent could be an attractive and viable option to target neuroendocrine cancers. JBI-802 inhibits the transcriptional regulator coREST via its component LSD1/HDAC6 therefore blocking neuroendocrine transdifferentiation and inducing cell death resulting in activity against neuroendocrine tumors. At the same time, this molecule has shown a good safety profile in toxicological studies. We have now identified a novel aspect of JBI-802 mechanism of action, the ability to induce downregulation of MYC RNA and degradation of MYC protein both in vitro and in animal models of two neuroendocrine tumors, small cell lung cancer and neuroendocrine prostate cancer JBI-802 showed significant anti-proliferative activity (0.2 to 1 µM) against several cancer cell lines as shown by Alamar blue or CTG assays. Sensitive ones included small cell lung cancer (SCLC), gastric cancer, breast cancer cell lines with RB1 mutation. Interestingly, dual inhibitor JBI-802 was also active in cell lines with MYC over-expression, while LSD1 selective inhibitors have been reported to be inactive in these cell lines. JBI-802 also inhibited MYC at RNA as well as protein level in hematological and solid tumors as assessed by RT-qPCR at RNA level and by Western blotting at protein level, while single agent LSD1 and HDAC6 inhibitors did not show significant modulation. JBI-802 also showed strong tumor growth inhibition of these tumors in mouse xenograft models. MYC levels showed a dose dependent inhibition in these tumors when tested at the end of the study. Only dual inhibition of both LSD1/HDAC6 with JBI-802 as opposed to single target inhibition is able to effectively downregulate MYC level and achieve efficacy in MYC amplified models in vivo and in vitro. This novel mechanism increases the potential population of neuroendocrine patients that could be sensitive to this compound, going beyond the proof of principle already established preclinically and clinically by single target LSD1 inhibitors. Therefore, by targeting 2 major pathways in neuroendocrine tumor development, JBI-802 novel mechanism of action is uniquely suited for the treatment of high unmet neuroendocrine tumors like small cell lung cancer, neuroendocrine prostate cancer and advanced, MYC amplified tumors. Based on this rationale, JBI-802 is being tested in phase 1/2 clinical trial focus on this type of tumors.

Citation Format: Dhanalakshmi Sivanandhan, Sridharan Rajagopal, Chandru Gajendran, Naveen Sadhu, Mohd Zainuddin, Ramachandraiah Gosu, Luca Rastelli. LSD1-HDAC6 dual inhibitor JBI-802 is an epigenetic modulating agent with a novel mechanism of action that target MYC amplification in multiple neuroendocrine tumor types. [abstract]. In: Proceedings of the AACR Special Conference: Cancer Epigenomics; 2022 Oct 6-8; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2022;82(23 Suppl_2):Abstract nr B029.

Novel tricyclic small molecule inhibitors of Nicotinamide N-methyltransferase for the treatment of metabolic disorders

Nicotinamide N-methyltransferase (NNMT) is a metabolic regulator that catalyzes the methylation of nicotinamide (Nam) using the co-factor S-adenosyl-L-methionine to form 1-methyl-nicotinamide (MNA). Overexpression of NNMT and the presence of the active metabolite MNA is associated with a number of diseases including metabolic disorders. We conducted a high-throughput screening campaign that led to the identification of a tricyclic core as a potential NNMT small molecule inhibitor series. Elaborate medicinal chemistry efforts were undertaken and hundreds of analogs were synthesized to understand the structure activity relationship and structure property relationship of this tricyclic series. A lead molecule, JBSNF-000028, was identified that inhibits human and mouse NNMT activity, reduces MNA levels in mouse plasma, liver and adipose tissue, and drives insulin sensitization, glucose modulation and body weight reduction in a diet-induced obese mouse model of diabetes. The co-crystal structure showed that JBSNF-000028 binds below a hairpin structural motif at the nicotinamide pocket and stacks between Tyr-204 (from Hairpin) and Leu-164 (from central domain). JBSNF-000028 was inactive against a broad panel of targets related to metabolism and safety. Interestingly, the improvement in glucose tolerance upon treatment with JBSNF-000028 was also observed in NNMT knockout mice with diet-induced obesity, pointing towards the glucose-normalizing effect that may go beyond NNMT inhibition. JBSNF-000028 can be a potential therapeutic option for metabolic disorders and developmental studies are warranted.

A novel selective inhibitor JBI-589 targets PAD4-mediated neutrophil migration to suppress tumor progression

Neutrophils are closely involved in the regulation of tumor progression and formation of pre-metastatic niches. However, the mechanisms of their involvement and therapeutic regulation of these processes remain elusive. Here, we report a critical role of neutrophil peptidylarginine deiminase 4 (PAD4) in neutrophil migration in cancer. In several transplantable and genetically engineered mouse models, tumor growth was accompanied by significantly elevated enzymatic activity of neutrophil PAD4. Targeted deletion of PAD4 in neutrophils markedly decreased the intratumoral abundance of neutrophils and led to delayed growth of primary tumors and dramatically reduced lung metastases. PAD4 mediated neutrophil accumulation by regulating the expression of the major chemokine receptor CXCR2. PAD4 expression and activity as well as CXCR2 expression were significantly upregulated in neutrophils from patients with lung and colon cancers compared to healthy donors, and PAD4 and CXCR2 expression were positively correlated in neutrophils from cancer patients. In tumor-bearing mice, pharmacological inhibition of PAD4 with the novel PAD4 isoform-selective small molecule inhibitor JBI-589 resulted in reduced CXCR2 expression and blocked neutrophil chemotaxis. In mouse tumor models, targeted deletion of PAD4 in neutrophils or pharmacological inhibition of PAD4 with JBI-589 reduced both primary tumor growth and lung metastases and substantially enhanced the effect of immune checkpoint inhibitors. Taken together, these results suggest a therapeutic potential of targeting PAD4 in cancer.

Abstract 2646: Novel, isoform selective PAD4 inhibitors for the treatment of cancer

Background: Peptidyl Arginine Deiminase 4 (PAD4/PADI4) is an enzyme that converts protein arginine or mono-methylarginine to citrulline. The PAD4-mediated hyper citrullination reaction in neutrophils causes the release of nuclear chromatin to form a chromatin network termed Neutrophil Extracellular Traps (NETs). NETs have been shown to be associated with several pathological processes including, fibrosis, ischemic stroke, preeclampsia, thrombosis, cancers, and other autoimmune diseases. In the context of cancer, tumors secrete chemokines such as CXCL1 and GCSF to recruit and prime neutrophils to form NETs, which in turn, facilitate cancer metastasis by forming Circulating Tumor Cell (CTC) clusters and potentially increasing tumor cell extravasation. Therefore, cancer cell endogenous PAD4 seems to play a significant role in metastasis, and inhibition of PAD4 could be a novel strategy to inhibit cancer progression and metastasis. Here, we describe a series of novel small molecule PAD4 inhibitors that are selective and orally bioavailable for the treatment of cancer.

Methods: Potency and selectivity were evaluated in ammonia release assay using recombinant PAD enzymes. Cellular potency was evaluated by assessing the modulation of citrullination in a human neutrophil-based assay. ADME surrogates and PK studies were conducted using appropriate preclinical models. In vivo efficacy studies were conducted in syngeneic mice tumor models.

Results: Multiple leads with strong in vitro potency on PAD4 (< 0.200 µM) were identified. One of the leads (JTxPAD4i) showed an IC50 of 0.102 µM against recombinant human PAD4 in the biochemical assay and a similar potency on mouse PAD4. It was selective against PAD1, PAD2, and PAD3 enzymes (IC50 > 10 µM). In the human neutrophil-based assay, JTxPAD4i inhibited H3-Histone citrullination with an IC50 of 0.125 µM. It showed an oral bioavailability of greater than 50% across species, including mouse, rat, and dog. Oral dosing with JTxPAD4i at 50 mg/kg, BID, in 4T1 mice syngeneic breast cancer model resulted in ~50% tumor growth inhibition (TGI) as compared to ~35% TGI with anti-PD1 antibody and was well tolerated. TGI was associated with strong inhibition of histone citrullination and myeloperoxidase (MPO) that are markers for NET formation. There was also a strong and significant inhibition in inflammatory cytokines, including IL-6, IL-17, and IL-1β in the tumor. Similar TGI was observed in additional breast and lung cancer syngeneic models with more than one PAD4 inhibitor from our lead series. Further studies with our lead molecules are underway to elucidate the mechanism of action of these PAD4 inhibitors.

Conclusion: These studies clearly emphasize the potential of PAD4 inhibition in the treatment of cancer and our lead PAD4 inhibitors are being profiled in advanced toxicology studies to be developed as a clinical candidate.

Citation Format: Dhanalakshmi Sivanandhan, Sridharan Rajagopal, Chandru G, Mohd Zainuddin, Naveen Sadhu, Ramachandraiah Gosu, Luca Rastelli, Amir Siddiqui, Sharad Singh, Rudresh G, Sadanand Mullurwar, Saravanan Kandan, Santosh Vishwakarma, Gurulingappa Hallur, Ravi Trivedi, Jeyaraj D A. Novel, isoform selective PAD4 inhibitors for the treatment of cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 2646.

Novel, small molecule inhibitors of PD-1/PD-L1 pathway

2597

Background: Programmed Cell Death 1 (PD-1) protein plays a key role in inhibiting immune responses and enhancing self-tolerance via modulation of T-cell activity, inducing T-cell apoptosis and inhibiting apoptosis of regulatory T cells. PD-L1 also plays an important role in various malignancies where it can attenuate the host immune response to tumor cells thereby favouring tumor progression and metastasis. High expression of PD-L1 in glioblastoma tumor tissues is associated with poor survival of patients, and PD-L1 may act as a prognostic predictor and an effective therapeutic target for glioblastoma. A number of monoclonal antibodies targeting PD-1/PD-L1 have approved for various malignancies. Still, efficacy of these antibodies in glioblastoma and brain metastasis continues to be moderate potentially owing to lack of or poor brain penetrance of these agents. Therefore, there is still a need for potent, selective small molecule PD-1/PD-L1 inhibitors with enhanced brain penetration in the treatment of such cancers. Methods: Rational design approaches were used to design novel small molecule PD-1/PD-L1 pathway inhibitors; potency of these inhibitors was assessed in an in-vitro TR-FRET assay. Checkpoints signalling reporter assays as well cell based PD-L1 dimerization assays were used to assess the mechanistic and functional effects. In vivo efficacy was assessed in orthotopic GBM as well as in syngeneic and humanized subcutaneous tumor models in mice. Results: Our lead PD-L1 inhibitor JBI-2174 showed strong in vitro IC50 of ̃1 nM in TR-FRET assay that measures interaction between hPD-1 and hPD-L1 and a picomolar IC50 against monkey PD-L1. In selectivity assays for immunooncology targets, JBI-2174 was highly selective for PD-L1. JBI-2174 also inhibited PD-L1/PD-1 mediated signalling essential for T-cell modulation. JBI-2174 induced dimerization of PD-L1 as observed by size exclusion chromatography, which was confirmed by co-crystal structure and recapitulated in cell based dimerization assay. Elucidation of the co-crystal structure, clearly demonstrated that JBI-2174 clearly interacts with multiple amino acids on PD-L1 that are critical for PD-1 binding. JBI-2174 showed excellent oral bioavailability across pre-clinical species and sustained brain exposure. In the in vivo efficacy studies, JBI-2174 showed comparable efficacy to the anti-PD-L1 antibody or Atezolizumab in syngeneic (4T1, CT-26) and in partially humanized models (MC-38/hPD-L1). Further, oral administration of JBI-2174 resulted in statistically significant increase in survival (Day 27 in control vs day 38 in treated, p < 0.05) in a mouse glioma orthotopic model. Conclusions: The oral bioavailability and brain exposure of this molecule will make it attractive for cancers with unmet medical needs such as GBM and brain metastasis. IND enabling studies are being initiated for this compound.

An Efficient Watermarking Based Matrix Manipulation and Optimization Based Cryptographic Method for Privacy Preservation in Biomedical Data

The biomedical processing of images is an important aspect of the modern medicine field and has an immense influence on the modern world. Automatic device assisted systems are immensely useful in order to diagnose biomedical images easily, accurately and effectively. Remote health care systems allow medical professionals and patients to work from different locations. In addition, expert advice on a patient can be received within a prescribed period of time from a specialist in a foreign country or in a remote area. Digital biomedical images must be transmitted over the network in remote healthcare systems. But the delivery of the biomedical goods entails many security challenges. Patient privacy must be protected by ensuring that images are secure from unwanted access. Furthermore, it must be effectively maintained so that nothing will affect the content of biomedical images. In certain instances, data manipulation can yield dramatic effects. A biomedical image safety method was suggested in this work. The suggested method will initially be used to construct a binary pixel encoding matrix and then to adjust matrix with the use of decimation mutation DNA watermarking principle. Afterwards to defend the sub keys couple privacy which was considered over the logical uplift utilization of tent maps and purpose. As acknowledged by chaotic (C-function) development, the security was investigated similar to transmission in addition to uncertainty. Depending on the preliminary circumstances, various numbers of random were generated intended for every map as of chaotic maps. An algorithm of Multi scale grasshopper optimization resource with correlation coefficient fitness function and PSNR was projected for choosing the optimal public key and secret key of system over random numbers. For choosing the validation process of optimization is to formulate novel model more relative stable to the conventional approach. In conclusion, the considered suggested findings were contrasted with current approaches protection that was appear to be successful extremely.

Abstract 1128: Selective, novel, small molecule PRMT5 inhibitors for treatment of cancer

Introduction: Arginine methylation deregulation in cancer has been well studied and PRMT5 which modulates dimethylation of arginine has emerged as an attractive therapeutic strategy in various cancer types, including lung cancer, lymphoma, glioblastoma, pancreatic cancers, etc. PRMT5 is over-expressed in multiple cancers leading to repression of tumor suppressor genes and genetic studies have identified it is a validated target in lymphoma. Recently, dysregulation of the splicing machinery in cancers has been identified to be one of the therapeutic vulnerabilities for PRMT5 inhibition, especially in glioblastoma. Therefore, inhibitors selectively targeting PRMT5 could be of high clinical value, especially in cancers with defects in spliceosome machinery.

Methods: Rational design and structure based drug design were used to identify novel PRMT5 inhibitors. To assess in vitro potency, flash plate based activity assay was used. Cell based activity of these inhibitors was assessed by measuring the symmetrical dimethylation of known cellular protein SmD3 by ELISA and Western blotting. Long term cell proliferation assays were used to assess the functional effect of PRMT5 inhibition. Tumor growth inhibition was measured in orthotopic glioblastoma model in mice.

Results: One of the lead PRMT5 inhibitors had an in vitro potency of 3 nM in the biochemical assay which translated well in the cell based SDMA ELISA where the EC50 was &lt;10 nM. Anti-proliferative activity of this molecule in lymphoma, leukaemia, SCLC, pancreatic, lung and glioblastoma cell lines ranged from ~16 nM to 1035 nM. This molecule showed acceptable in vitro ADME properties in terms of aqueous solubility and metabolic stability and excellent oral bioavailability in rodent pharmacokinetics. In Z-138 mantle cell lymphoma xenograft model, oral administration of the lead compound at 50 mg/kg resulted in strong and complete (~95 %) tumour growth inhibition and with a concomitant complete inhibition of SDMA. The lead compound was well tolerated with no reduction in body weight at the tested doses. Interestingly, this molecule showed excellent brain exposure sufficient to achieve target engagement for 10h and significant tumour growth inhibition of orthotopic brain tumors by oral dosing. Repeat dose non-GLP study in rodents clearly demonstrated the safety of this molecule.

Conclusion: Given the therapeutic importance of PRMT5 in glioblastoma and other lymphomas, this molecule will be extremely valuable in treating these cancers both as a standalone therapy and in combination with other standard of care agents.

Citation Format: Dhanalakshmi Sivanandhan, Sridharan Rajagopal, Naveen Sadhu M, Chandru Gajendran, Saravanan Vadivelu, Natarajan Tamizharasan, Indu N. Swamy, Santhosh Viswakarma, Amir Siddiqui, Saif wahid, Mohammed Zainuddin, Rudresh G, Prashanthi Daram, Ramchandraiah Gosu, Dinesh Tiagaraj, Shivani Garapaty, Sreekala Nair, Namratha Kapoor. Selective, novel, small molecule PRMT5 inhibitors for treatment of cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 1128.

Novel Inhibitors of Nicotinamide-N-Methyltransferase for the Treatment of Metabolic Disorders

Nicotinamide-N-methyltransferase (NNMT) is a cytosolic enzyme catalyzing the transfer of a methyl group from S-adenosyl-methionine (SAM) to nicotinamide (Nam). It is expressed in many tissues including the liver, adipose tissue, and skeletal muscle. Its expression in several cancer cell lines has been widely discussed in the literature, and recent work established a link between NNMT expression and metabolic diseases. Here we describe our approach to identify potent small molecule inhibitors of NNMT featuring different binding modes as elucidated by X-ray crystallographic studies.

Novel dual LSD1/HDAC6 inhibitors for the treatment of multiple myeloma

Lysine specific demethylase 1 (LSD1) and HDAC6 are epigenetic proteins associated with several diseases, including cancer and combined inhibition of these proteins could be highly beneficial in treating some cancers such as AML, MM and solid tumors. Multiple myeloma (MM) is a challenging cancer with fast relapse rate where novel treatment options are the need of the hour. We have designed and developed novel, LSD1 and HDAC6 selective dual inhibitors to target MM. Our dual inhibitor compound 1 shows superior potency in multiple MM cell lines. In MM.1S xenograft model compound 1 shows superior efficacy compared to single agent LSD1 and HDAC6 inhibitors by oral administration and is well tolerated. Further evaluation of the molecule in other cancers is in progress.

Validated LC-MS/MS Method for Simultaneous Quantitation of SAFit-1 and SAFit-2 in Mice Plasma: Application to a Pharmacokinetic Study

SAFit-1 and SAFit-2 are selective FKBP51 (FK506-binding protein 51) ligands. In this paper, we present the development and validation data of an LC-MS/MS method for the simultaneous quantitation of SAFit-1 and SAFit-2 in mice plasma as per FDA regulatory guideline. SAFit-1 and SAFit-2 along with internal standard were extracted from mice plasma using liquid-liquid extraction method. Chromatographic resolution of SAFit-1, SAFit-2 and the internal standard (warfarin) was achieved on an X-Terra phenyl column using 0.2% formic acid:acetonitrile (20:80, v/v) as an eluent, which was delivered at a flow-rate of 0.9 mL/min. The MS/MS ion transitions monitored were m/z 748.4→420.4, 803.7→384.3 and 309.2 →163.2 for SAFit-1, SAFit-2 and the internal standard, respectively. The linearity range was 2.45–2446 ng/mL for both SAFit-1 and SAFit-2. The intra- and inter-day accuracy and intra- and inter-day precision were in the range of 0.90–1.07 and 2.38–10.8%, respectively for SAFit-1; 0.97–1.15 and 0.23–12.5%, respectively for SAFit-2. Both SAFit-1 and SAFit-2 were found to be stable in stability studies (up to three freeze-thaw cycles and for long-term at −80°C for 30 days) and processed (bench-top for 3 h and in in-injector for 16 h) samples. The application of the validated method was shown in a pharmacokinetic study in mice.

Systemic adjuvant therapy for adult patients at high risk for recurrent cutaneous or mucosal melanoma: an Ontario Health (Cancer Care Ontario) clinical practice guideline

Background

Previous versions of the guideline from the Program in Evidence-Based Care (pebc) at Ontario Health (Cancer Care Ontario) recommended that the use of high-dose interferon alfa 2b therapy be discussed and offered to patients with resected cutaneous melanoma with a high risk of recurrence. Subsequently, several clinical trials in patients with resected or metastatic melanoma found that immune checkpoint inhibitors and targeted therapies have a benefit greater than that with interferon. It was therefore considered timely for an update to the guideline about adjuvant systemic therapy in melanoma.

Methods

The present guideline was developed by the pebc and the Melanoma Disease Site Group (dsg). Based on a systematic review from a literature search conducted using medline, embase, and the Evidence Based Medicine Reviews databases for the period 1996 to 28 May 2019, the Working Group drafted recommendations. The systematic review and recommendations were then circulated to the Melanoma dsg and the pebc Report Approval Panel for internal review; the revised document underwent external review.

Recommendations

For patients with completely resected cutaneous or mucosal melanoma with a high risk of recurrence, the recommended adjuvant therapies are nivolumab, pembrolizumab, or dabrafenib-trametinib for patients with BRAF V600E or V600K mutations; nivolumab or pembrolizumab are recommend for patients with BRAF wild-type disease. Use of ipilimumab is not recommended. Molecular testing should be conducted to help guide treatment decisions. Interferon alfa, chemotherapy regimens, vaccines, levamisole, bevacizumab, bacillus Calmette-Guérin, and isolated limb perfusion are not recommended for adjuvant treatment of cutaneous melanoma except as part of a clinical trial.

Isolated diastolic hypertension and its risk factors in semi-rural population of South India

Background

Isolated diastolic hypertension (IDH) has been actively discussed for the last two decades because of its prevalence in a younger population and its association with cardiovascular disease. Furthermore, the association of IDH is significant in South Asian Countries such as India because relatively younger populations are known to have a higher risk of cardiovascular events.

Objective

The objective of this study is to find prevalence of IDH and its risk correlates in a semiurban population of South Indian state of Andhra Pradesh.

Methods

Data were collected using the modified World Health Organization - STEPwise approach to Surveillance (WHO STEPS) questionnaire for 16,636 individuals from a group of villages under Thavanampalle Mandal. Collated data were analyzed for prevalence and risk factors of IDH.

Results

Prevalence of IDH was found to be 4.0% with mean age of 46.0 (±SD 13.6) years and a relatively higher prevalence in men (5.3%) as compared with women (3.2%). The prevalence of IDH peaked in the fifth decade of life (40–49 years of age) and declined thereafter. Among various risk factors that were analyzed for their association with IDH, only age, body weight, and body mass index retained their significance in multivariate binary logistic regression analysis.

Conclusion

There is a significant prevalence of IDH below 50 years of age in the semiurban population of South India. As IDH in young and middle age is known to be associated with increased risk of cardiovascular events and end organ involvement, it highlights need for study and development of effective IDH management strategies to reduce associated morbidity and mortality.

Abstract 11: Novel dual inhibitors of LSD1-HDAC6/8 for treatment of cancer

Introduction: Lysine Specific Demethylase 1 (LSD1) is a flavin adenine dinucleotide (FAD)-dependent amine oxidase that has been reported to be over-expressed in many malignant tumors. Down-regulation of LSD1 has been shown to effectively treat cancers by inducing re-expression of aberrantly silenced genes. Studies have shown that LSD1 may contribute to acute myelogenous leukemia pathogenesis by inhibiting the normal pro-differentiative function of ATRA, paving the way for new combinatorial therapies for AML. Similarly, HDAC isoform selective inhibitors are beginning to be explored as less toxic alternatives to panHDAC inhibitors in select cancers. Further, combined inhibition of LSD1 and HDAC has been shown to be more efficacious in inhibiting multiple cancers. Here, we show that JBI-295, a dual inhibitor targeting both LSD1 and HDAC6/8 shows stronger efficacy without enhancing systemic toxicity, in a subset of AML and JAK-dependent myeloproliferative cancer.

Methods: Computational chemistry approaches were used to design LSD1 specific and LSD1-HDAC dual inhibitors. To assess in vitro LSD1 potency, TR-FRET assay was used. For assessing in vitro HDAC activity fluorescence based HDAC6 activity assay was performed. Western blotting was used to assess biomarkers of LSD1 and HDAC inhibition. Alamar blue cytotoxicity assay was used to assess cell proliferation.

Results: Several compounds from this series show strong in vitro potency against LSD1 with more than excellent selectivity against MAOs. JBI-295 one of the lead dual molecules, showed strong LSD1 potency (IC50 of 0.07 μM) and isoform selective HDAC6/8 activity (IC50 of 0.006 and 0.08 µM on HDAC6 and HDAC8, respectively), with about 100 fold selectivity against other HDAC isoforms. JBI-295 showed strong anti-proliferative activity on leukaemia and multiple myeloma cell lines. In cell based and in vivo target engagement studies there was a concomitant increase in CD11b, CD86 and GFI1b and tubulin acetylation levels. JBI-295 was more efficacious in inhibiting the growth of leukemia HEL92.1.7 xenograft by oral administration when compared to IP administration of ACY-1215, a HDAC6 selective inhibitor. Stronger tumor growth inhibition was also observed in melanoma A375 xenograft model as compared to inhibitors with single activity. In addition, JBI-295 showed single agent activity in a syngeneic murine colon cancer model CT26 and also resulted in stronger tumor growth inhibition when combined with anti-PDL1 antibody.

Conclusion: The data obtained demonstrate that dual LSD1-HDAC6/8 inhibitors could serve as novel, effective therapeutic agents for treatment of select subset of cancer. Advanced efficacy and toxicology studies with JBI-295 are in progress.

Citation Format: Dhanalakshmi Sivanandhan, Sridharan Rajagopal, Sreekala Nair, Chandru Gajendran, Dimpy Ghosh, P Nagaraj, Subramanyam J. Tantry, Purushottam Dewang, Mahanandeesha S. Hallur, Kannan Murugan, Srinatha K. C, Damodara Kuntrapaku, M Dilipkumar, R Sharma, S Meghashree, Durga Prasanna Kumar, Suraj P. Ingle, Mohd Zainuddin, A B. Vinod, Sriram Rajagopal. Novel dual inhibitors of LSD1-HDAC6/8 for treatment of cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 11.

P91 Post-operative pain in neurosurgery

Objectives

Are the analgesic guidelines for those neurosurgical operations associated with major and complex major pain consistently followed? Is there a correlation between adherence and post-operative pain?

Design

Patients undergoing spinal surgery and foramen magnum decompressions were visited on the first post-operative day (D1). They provided their pain score subjectively (0=nil; 10=worst ever experienced); objectively we recorded whether they could move in/out of bed without pain limitation.

Subjects

n=57 consecutive patients undergoing elective major and complex major pain neurosurgery between April and June 2018 at the NHNN, Queen Square.

Methods

A proforma was completed on D1. The patients consented to take part and answered three questions. We examined what (if any) analgesics they were admitted on, and what had been prescribed to cover the post-operative period. This was compared against the appropriate guideline for that category of operation.

Results

Guidelines were only followed in 16/57 (28.1%) cases; not followed in 41/57 (71.9%). On an unpaired T-test: 2-tailed P value=0.0195. Where guidelines were followed, the mean pain score reported was: 3.75 (SD 2.72) Where not followed, the mean pain score was 5.46 (SD 2.29). So with a 95% confidence interval −3.41 to −0.29, there is a significant difference between the pain in those prescribed according to the guidelines and those that were not.

Conclusions

The pain guidelines are not routinely followed. Most commonly this was due to no prescription for a non-steroidal anti-inflammatory agent. We suggest regular sessions of education of the guidelines. Cycle 2 closed the loop of the audit. We re-reviewed adherence and pain scores and found guidelines were followed in 34% of cases, which represented a 6% improvement. On a paired two-tailed P value=0.0794. The mean pain score where guidelines were followed=3.42 (SD1.62) against a mean=4.74 (SD 1.89) where guidelines were not followed.

Novel KV7 ion channel openers for the treatment of epilepsy and implications for detrusor tissue contraction

Neuronal voltage-gated potassium channels, K_V7s, are the molecular mediators of the M current and regulate membrane excitability in the central and peripheral neuronal systems. Herein, we report novel small molecule K_V7 openers that demonstrate anti-seizure activities in electroshock and pentylenetetrazol-induced seizure models without influencing Rotarod readouts in mice. The anti-seizure activity was determined to be proportional to the unbound concentration in the brain. K_V7 channels are also expressed in the bladder smooth muscle (detrusor) and activation of these channels may cause localized undesired effects. Therefore, the impact of individual K_V7 isoforms was investigated in human detrusor tissue using a panel of K_V7 openers with distinct activity profiles among K_V7 isoforms. KCNQ4 and KCNQ5 mRNA were highly expressed in detrusor tissue, yet a compound that has significantly reduced activity on homomeric K_V7.4 did not reduce detrusor contraction. This may suggest that the homomeric K_V7.4 channel plays a less significant role in bladder contraction and further investigation is needed.

Abstract 5860: Novel, first-in-class dual inhibitors of lysine specific demethylase 1 (LSD1) and histone deacetylatse 1 (HDAC) for treatment of cancer

Introduction: LSD1 is a flavin adenine dinucleotide (FAD)-dependent amine oxidase that removes methyl groups from mono- or dimethylated histone H3 lysine 4. Studies have shown that LSD1 contributes to acute myelogenous leukaemia pathogenesis and patients that are non responders to ATRA respond to LSD1-ATRA combination treatment in clinic. Recent studies have shown that there is cross-talk between two components of CoREST complex, LSD1 and HDAC1/2 and combined inhibition of these targets has been shown to be more efficacious in multiple cancers. Therefore, dual inhibitors targeting both LSD1 and HDAC could be useful in treating cancers. To test the hypothesis, we have developed a set of molecules that have dual activity on LSD1 and HDACs.

Methods: To assess in vitro LSD1potency, TR-FRET assay was used. For assessing HDAC activity fluorescence based HDAC activity assay was performed. Western blotting and RT-qPCR were used to assess biomarkers of LSD1 and HDAC1/2 inhibition. Alamar blue cytotoxicity assay was used to assess cell proliferation. Xenograft models were used to assess in vivo efficacy.

Results: Dual inhibitors show strong in vitro potency comparable to advanced clinical candidates, against LSD1. On HDAC1/2 these molecules showed comparable IC50 as marketed HDAC1/2 specific drugs. Interestingly, these dual inhibitors lead to stronger and complete inhibition of cell proliferation in broader types of cancer cell lines, including, acute myeloid leukemia, multiple myeloma, hepatocellular carinoma and small cell lung cancer when compared to LSD1 specific inhibitor GSK2879552. Target engagement studies confirm the concomitant increase in mRNA levels of GFI1b, CD11b, CD86 and H3K9 acetylation levels. In vitro activity also shows a clear translation in efficacy studies. JBI128, one of the lead molecules from this series was tested in multiple in vivo studies, including, non-small cell and small cell lung cancer, where it not only shows single agent activity, but can also be combined with other targeted agents or SoC safely. In addition, combination of JBI128 with immune checkpoint inhibitor anti-PDL1 antibody in the CT26 syngeneic model showed much stronger efficacy as compared to either of the single agents. This clearly suggests that these dual inhibitors in addition to being epigenetic modulators in the cancer cells also have a role in immune modulation thereby contributing to stronger efficacy. Further studies in terms of gene expression analysis are underway to understand the molecular mechanism behind the additional activity/efficacy of these dual inhibitors.

Conclusion: These LSD1-HDAC dual inhibitors have the potential to be developed as first-in-class therapies that could offer stronger clinical efficacy compared to LSD1 or HDAC inhibitor alone. Further mechanistic and combination studies with standard therapies are in progress.

Citation Format: Dhanalakshmi Sivanandhan, Sreekala Nair, Subramaniyam Tantry, Sridharan Rajagopal, Mahanandeesha Hallur, Kannan M, Srinatha KC, Damodara K, Dilipkumar M, Chandru G, Dimpy Ghosh, Pradeep N, Anuj Kumar Singh, Mohd Zainuddin, Rudresh G, Radha Sharma, Meghashree S, Durga P. Kumar, Purushottam Dewang, Sriram Rajagopal. Novel, first-in-class dual inhibitors of lysine specific demethylase 1 (LSD1) and histone deacetylatse 1 (HDAC) for treatment of cancer [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 5860.

Abstract 1382: Novel dual inhibitors of LSD1-HDAC6/8 for treatment of cancer

LSD1 is an FAD-dependent amine oxidase that removes methyl groups from mono- or dimethylated histone H3 lysine 4 (H3-K4) as a part of CoREST repressor complex. Recent studies have shown that there is crosstalk between two components of CoREST complex, LSD1 and HDAC, which provides an advantage to cancer cell proliferation and survival by regulating key signaling pathways. Accordingly, combined inhibition of LSD1 and HDAC has been shown to be more efficacious in inhibiting the growth of glioblastoma, AML and breast cancer. Therefore, dual inhibitors targeting both LSD1 and HDAC could be useful in treating several cancers effectively without enhancing systemic toxicity mediated by administration of multiple drugs. To test the hypothesis, we have developed a set of molecules that either have LSD1 activity alone or dual activity on LSD1 and HDAC. Computational chemistry approaches were used to design LSD1-HDAC dual inhibitors. In vitro LSD1 potency was assessed by TR-FRET assay and in vitro HDAC activity by fluorimetric HDAC activity assay. Western blotting and RT qPCR were used to assess biomarkers of LSD1 and HDAC inhibition. Alamar blue cytotoxicity assay was used to assess cell proliferation. Multiple compounds from this series show an in vitro potency of less than 0.05 μM against LSD1 with more than 100-fold selectivity against MAOs. The dual inhibitors showed stronger activity on HDAC6/8. JBI-097, one such dual molecule with LSD1/HDAC/6/8 selectivity, showed an IC50 of 0.007uM on LSD1 and an IC50 of 0.06 and 0.1uM on HDAC6 and HDAC8, respectively, with about 100-fold selectivity against other HDAC isoforms. JBI-097 showed strong antiproliferative activity on leukemia and multiple myeloma cell lines. In MM.1S cell line, JBI-097 showed stronger potency when compared to LSD1 inhibitor GSK2879552 and HDAC6 inhibitor ACY1215. In cell-based and in vivo target engagement studies there was a concomitant increase in CD11b, CD86 and GFI1b and tubulin acetylation levels. JBI-097 was more efficacious in inhibiting the growth of HEL92.1.7 xenograft by oral administration when compared to IP administration of an HDAC inhibitor. In MM.1S tumor model, JBI-097 showed stronger effect in inhibiting tumor growth when compared to LSD1 inhibitor and HDAC6 inhibitor used as single agents. Further, combination with topotecan resulted in complete tumor growth inhibition of MM.1S xenograft. The data obtained demonstrate that it is feasible to design dual LSD1-HDAC6/8 inhibitors that retain individual activity and potently inhibit cell proliferation, and such inhibitors could serve as powerful therapeutic agents for cancer. Further understanding of mechanisms to identify the right tool compound is in progress.

Citation Format: Sivanandhan Dhanalakshmi, Sridharan Rajagopal, Sreekala Nair, Chandru Gajendran, Dimpy Ghosh, Subramanyam Janardhan Tantry, Purushottam Dewang, Mahanandeesha Hallur, M Kannan, Srinatha KC, Damodara Kuntrapaku, M Dilipkumar, Radha Sharma, S Meghashree, D P. Kumar, Mohd Zainuddin, A B. Vinod, Sriram Rajagopal. Novel dual inhibitors of LSD1-HDAC6/8 for treatment of cancer [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 1382.

Diagnostic yield in the evaluation of dysphagia: experience at a single tertiary care center

Evaluation of dysphagia typically starts with esophagogastroduodenoscopy (EGD); further testing is pursued if this is negative. When no mucosal, structural, or motor esophageal disorders are identified with persisting symptoms, functional dysphagia is considered. We evaluated outcomes in patients undergoing EGD for dysphagia, and estimated prevalence of functional dysphagia. The endoscopy database at single tertiary care center was interrogated to identify EGDs performed for an indication of 'dysphagia' over a 12-month period (2008-09). Electronic medical records were reviewed over the next 8 years to assess if an etiology was identified. Data were analyzed to assess the diagnostic yield of endoscopy and subsequent tests in the evaluation of dysphagia. Of 5486 EGDs, 822 (15.0%) were performed for dysphagia in 694 patients (58.4 ± 0.6 year, range: 18-95 year, 55.8% female). Of these, 529 (76.2%) had EGD findings that explained dysphagia; another 22 (3.2%) had findings on histopathology. Of the remainder 143 patients (20.6%) with normal index EGD, 38 (26.6%) patients underwent barium esophagram with 15 (39.5%) having abnormal studies. 19 patients (13.3%) underwent esophageal high resolution manometry with 12 (63.2%) being abnormal, and 7 had a mechanism for dysphagia on alternate testing. A repeat EGD was abnormal in 6 patients, while 45 patients were lost to follow-up. 42 patients had complete resolution of symptoms despite normal endoscopy, of which 30 were treated empirically with a proton pump inhibitor (PPI). Only 16 patients had no findings on evaluation, and had continued dysphagia symptoms, representing true functional dysphagia in 2.3% of all dysphagia patients and 11.2% of patients with normal EGD. Endoscopy remains the test with the highest yield (over 75%) for a diagnosis in patients presenting with dysphagia; secondary tests are useful when endoscopy does not provide a diagnosis. Benign strictures and GERD-related etiologies are leading causes; PPI therapy is useful even when testing is negative. Functional dysphagia is extremely rare, accounting for <2.5% of all dysphagia.

Novel nicotinamide analog as inhibitor of nicotinamide N-methyltransferase

Nicotinamide N-methyltransferase (NNMT) has been linked to obesity and diabetes. We have identified a novel nicotinamide (NA) analog, compound 12 that inhibited NNMT enzymatic activity and reduced the formation of 1-methyl-nicotinamide (MNA), the primary metabolite of NA by ∼80% at 2 h when dosed in mice orally at 50 mg/kg.

Immuno-detection of cleaved SNAP-25 from differentiated mouse embryonic stem cells provides a sensitive assay for determination of botulinum A toxin and antitoxin potency

Botulinum toxin type A is a causative agent of human botulism. Due to high toxicity and ease of production it is classified by the Centres for Disease Control and Prevention as a category A bioterrorism agent. The same serotype, BoNT/A, is also the most widely used in pharmaceutical preparations for treatment of a diverse range of neuromuscular disorders. Traditionally, animals are used to confirm the presence and activity of toxin and to establish neutralizing capabilities of countermeasures in toxin neutralization tests. Cell based assays for BoNT/A have been reported as the most viable alternative to animal models, since they are capable of reflecting all key steps (binding, translocation, internalization and cleavage of intracellular substrate) involved in toxin activity. In this paper we report preliminary development of a simple immunochemical method for specifically detecting BoNT/A cleaved intracellular substrate, SNAP-25, in cell lysates of neurons derived from mouse embryonic stem cells. The assay offers sensitivity of better than 0.1LD50/ml (3fM) which is not matched by other functional assays, including the mouse bioassay, and provides serotype specificity for quantitative detection of BoNT/A and anti-BoNT/A antitoxin. Subject to formal validation, the method described here could potentially be used as a substitute for the mouse bioassay to measure potency and consistency of therapeutic products.

Validated LC-MS-MS Method for Determination of SF0034 in Mice Plasma: Application to a Pharmacokinetic Study in Mice

A rapid and sensitive assay method has been developed and validated using liquid chromatography coupled to tandem mass spectrometry with electrospray ionization in the positive-ion mode for the estimation of SF0034 in mice plasma. The assay procedure involves a simple protein precipitation of SF0034 and tolbutamide (internal standard, IS) from mice plasma. Chromatographic separation was performed on an Atlantis dC18 column using an isocratic mobile phase comprising 0.2% formic acid:acetonitrile (10:90, v/v) at a flow rate of 0.60 mL/min. The total run time was 2.5 min. For mass spectrometric detection, the multiple reaction monitoring was used and ion transitions monitored were m/z 322 → 248 for SF0034 and 271 → 155 for IS. Method validation was performed as per regulatory guidelines and the results met the acceptance criteria. A calibration curve was constructed in the range of 2.08-2,078 ng/mL. The intra- and inter-day precision was in the range of 1.06-14.4% and 7.16-11.7%, respectively. This novel method has been applied to a pharmacokinetic study in mice.

Crystal structures of monkey and mouse nicotinamide N-methyltransferase (NNMT) bound with end product, 1-methyl nicotinamide

Nicotinamide N-methyltransferase (NNMT) is a S-adenosyl-l-methionine (SAM)-dependent enzyme that catalyzes N-methylation of nicotinamide (NA) and other pyridines to form N-methyl pyridinium ions. Here we report the first ternary complex X-ray crystal structures of monkey NNMT and mouse NNMT in bound form with the primary endogenous product, 1-methyl nicotinamide (MNA) and demethylated cofactor, S-adenosyl-homocysteine (SAH) determined at 2.30 Å and 1.88 Å respectively. The structural fold of these enzymes is identical to human NNMT. It is known that the primary endogenous product catalyzed by NNMT, MNA is a specific inhibitor of NNMT. Our data clearly indicates that the MNA binds to the active site and it would be trapped in the active site due to the formation of the bridge between the pole (long helix, α3) and long C-terminal loop. This might explain the mechanism of MNA acting as a feedback inhibitor of NNMT.

Abstract 5578: Small molecule modulators to understand the role of IDO1 and TDO2 in cancer

Introduction: Tumor immune escape mechanisms have been established as suitable targets for cancer therapy. Among these, tryptophan catabolism plays a central role in creating an immunosuppressive environment, leading to tolerance to potentially immunogenic tumor antigens. Tryptophan catabolism is initiated by either indoleamine 2,3-dioxygenase (IDO1/2) or tryptophan 2,3-dioxygenase 2 (TDO2), resulting in biostatic tryptophan starvation and l-kynurenine production. Recent literature has shown that IDO1 and TDO2 are expressed in multiple tumors, including solid tumors and play key roles in tumor progression other than immune escape. It has also been shown that IDO1 and TDO2 play distinct roles in driving the downstream effectors suggesting that their roles are perhaps non-redundant. Therefore, we developed series of novel small molecule modulators against IDO1 and TDO2 to understand their role in disease biology for multiple indications including cancer, depression and autoimmune disorders.

Methods: Rational design approaches were used to design novel IDO1 and TDO2 specific modulators; Potency of these inhibitors was assessed in the in vitro assays using purified IDO1 and TDO2 enzymes and in IDO1 and TDO2 over-expressing HEK293T cells by measuring the formation of kynurenine.

Results: In the in vitro biochemical assay using purified human TDO2, one of the NCEs from inhibitor series showed an IC50 of 0.09 μM against TDO2. Against purified human IDO1, this compound was inactive up to 30 μM, thereby showing &gt;300-fold selectivity against IDO1. This TDO2 inhibitory activity translated well in TDO2-overexpressing HEK293 cells and, these NCEs inhibited kynurenine formation with an EC50 of ~2.5 μM. A second chemical series showed comparable dual inhibition of IDO1 and TDO2 activity. One of the molecules from this series showed IC50 of 0.2 and 0.08 μM in the biochemical assay and 1.7 and 0.8 μM in the cell based assay against IDO1 and TDO2, respectively. In addition, another series of NCEs showed strong activation of IDO1 and TDO2 activity. As compared to untreated control, formation of kynurenine was increased in a dose-dependent manner as observed by increase in fluorescence up to of 3-10 folds. One of the compounds from this series showed an EC50 of ~20- 30 μM in the biochemical assay as well as in 293T-based assay. Further mechanistic studies to understand the immune modulatory activity of these selective TDO2 modulators is underway. These tool compounds are being further optimized for potency and ADME properties to be developed as potential drug candidates.

Conclusion: To our knowledge such IDO1 and TDO2 specific small molecule activators have not been reported earlier. Therefore, these activators and inhibitors would serve as useful tool compounds in understanding the specific role(s) of IDO1 and TDO2 in disease biology and would also provide us the opportunity to target this pathway for various diseases, including cancer.

Citation Format: Shivani Rao Garapaty, Dhanalakshmi Sivanandhan, Guru Pavan Kumar Seerapu, Surendra Naidu, Shalini Chakelam, Pradeep Nagaraj, Reshma Das, Saravanan Vadivelu, Pravin Iyer, Chandrika Mulakala, Kannan Murugan, Somnath Mondal, Anjali Gautam, Saravanan Kandan, Manish Kumar Thakur, Sridharan Rajagopal, Sriram Rajagopal. Small molecule modulators to understand the role of IDO1 and TDO2 in cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 5578. doi:10.1158/1538-7445.AM2017-5578

Novel hydroxamates potentiated in vitro activity of fluconazole against Candida albicans

A set of 12 novel hydroxamate compounds (NHCs), structurally designed as inhibitors of histone deacetylase (HDAC) enzyme, were synthesized at our facility. These were adamantane derivatives with N-hydroxyacetamide as pharmacophore, and each of these compounds was tested for potentiating activity on fluconazole. The concentration of fluconazole which completely inhibited (concentration of complete inhibition [CCI]) the growth of Candida albicans ATCC 90028 and C. albicans ATCC 64550 was determined by micro-dilution method in the absence and presence of NHCs. The CCI of fluconazole without the NHC combination was 64 μg/ml and 1024 μg/ml against C. albicans ATCC 90028 and C. albicans ATCC 64550, respectively. The majority of the NHCs potentiated the fluconazole activity markedly as CCI of fluconazole against C. albicans ATCC 90028 reduced to 0.25 μg/ml. Similarly, CCI of fluconazole against C. albicans ATCC 64550 reduced to 4–8 μg/ml in combination with majority of NHCs while the best activity was displayed by the compound 1 with a reduction of CCI to 0.5 μg/ml. The study results revealed the potential usage of hydroxamate derivatives, structurally designed as HDAC inhibitors to enhance the activity of fluconazole against C. albicans.

Validation of an LC-MS/MS method for simultaneous detection of four HDAC inhibitors - belinostat, panobinostat, rocilinostat and vorinostat in mouse plasma and its application to a mouse pharmacokinetic study

A sensitive and rapid LC-MS/MS method was developed and validated for the simultaneous quantitation of four HDAC inhibitors, namely belinostat (BST), panobinostat (PST), rocilinostat (RST) and vorinostat (VST), in mouse plasma as per regulatory guidelines. The analytes and internal standard were extracted from 50 μL mouse plasma by protein precipitation, followed by chromatographic separation using an Atlantis C₁₈ column with an isocratic mobile phase comprising 0.1% formic acid-acetonitrile (25:75, v/v) at a flow rate of 0.5 mL/min within 2.5 min. Detection and quantitation were done by multiple reaction monitoring on a triple quadrupole mass spectrometer following the transitions: m/z 319 → 93, 350 → 158, 434 → 274 and 265 → 232 for BST, PST, RST and VST, respectively, in the positive ionization mode. The calibration curves were linear from 2.92 to 2921 ng/mL for BST and PST and from 1.01 to 1008 ng/mL for RST and VST with r²  ≥ 0.99 for all of the analytes. The intra- and inter-batch accuracy and precision (CV) across quality controls varied from 85.5 to 112% and from 2.30 to 12.5, respectively, for all of the analytes. Analytes were found to be stable under different stability conditions. The method was applied to an i.v. pharmacokinetic study in mice.

In vivo effective dibenzo[b,d]furan-1-yl-thiazoles as novel PDE-4 inhibitors

Herein we report the synthesis, PDE-4B and TNF-α inhibitory activities of a few dibenzo[b,d]furan-1-yl-thiazole derivatives. The hydroxycyclohexanol amide derivatives 14, 18, 24, 29, 31 and 33 exhibited promising in vitro PDE-4B and TNF-α inhibitory activities. Compound 24 showed good systemic availability in preclinical animal models and was also found to be non-toxic (exploratory mutagenicity test). Further it exhibited promising results in in vivo asthma/COPD and Uveitis models.

Clinical presentation, management, and outcomes in the Indian Heart Rhythm Society-Atrial Fibrillation (IHRS-AF) registry

Aim

A national atrial fibrillation (AF) registry was conducted under the aegis of the Indian Heart Rhythm Society (IHRS), to capture epidemiological data-type of AF, clinical presentation and comorbidities, current treatment practices, and 1-year follow-up outcomes.

Methods

A total of 1537 patients were enrolled from 24 sites in India in the IHRS-AF registry from July 2011 to August 2012. Their baseline characteristics and follow-up data were recorded in case report forms and subsequently analyzed.

Results

The average age of Indian AF patients was 54.7 years. There was a marginal female preponderance – 51.5% females and 48.5% males. At baseline, 20.4% had paroxysmal AF; 33% had persistent AF; 35.1% had permanent AF and 11% had first AF episode. At one-year follow-up, 45.6% patients had permanent AF.

Rheumatic valvular heart disease (RHD) was present in 47.6% of patients. Hypertension, heart failure, coronary artery disease, and diabetes were seen in 31.4%, 18.7%, 16.2%, and 16.1%, respectively.

Rate control was the strategy used in 75.2% patients, digoxin and beta-blockers being the most frequently prescribed rate-control drugs. Oral anticoagulation (OAC) drugs were used in 70% of patients. The annual mortality was 6.5%, hospitalization 8%, and incidence of stroke 1%.

Conclusions

In India, AF patients are younger and RHD is still the most frequent etiology. Almost two-third of the patients have persistent/permanent AF. At one-year follow-up, there is a significant mortality and morbidity in AF patients in India.

Systematic synthesis and analysis of change in morphology, electronic structure and photoluminescence properties of 2,2′-dipyridyl intercalated MoO3 hybrid nanostructures and investigation of their photocatalytic activity

An organic–inorganic hybrid was synthesized using 2,2′-dipyridyl and MoO₃ nanorods via simple hydrothermal method. Here, dipyridyl has acted as stretching molecule and bonded the MoO₃ nanorods together along the length to form hybrid micro crystals.

Sensitive method for the determination of rocilinostat in small volume mouse plasma by LC-MS/MS and its application to a pharmacokinetic study in mice

A highly sensitive, specific and rapid LC-ESI-MS/MS method has been developed and validated for the quantification of rocilinostat in small volume mouse plasma (20 μL) using vorinostat as an internal standard (IS) as per regulatory guidelines. Sample preparation was accomplished through a protein precipitation procedure with acetonitrile. Chromatography was achieved on Prodigy ODS-2 column using a binary gradient using mobile phase A (0.2% formic acid in water) and B (acetonitrile) at a flow rate of 0.38 mL/min. The total chromatographic run time was 4.1 min and the elution of rocilinostat and IS occurred at ~3.2 and 2.9 min, respectively. A linear response function was established in the concentration range of 0.28-1193 ng/mL in mouse plasma. The intra- and inter-day accuracy and precisions were in the ranges of 3.12-8.93 and 6.41-11.6%, respectively. This novel method has been applied to a pharmacokinetic study in mice. Copyright © 2016 John Wiley & Sons, Ltd.

Aptamer-based label-free detection of PDGF using ruthenium(II) complex as luminescent probe

We report a simple, cost-effective, and label-free detection method, consisting of a platelet-derived growth factor (PDGF) binding aptamer and hydrophobic Ru(II) complex as a sensor system for PDGF. The binding of PDGF with the aptamer results in the weakening of the aptamer-Ru(II) complex, monitored by luminescence signal. A substantial enhancement in the luminescence intensity of Ru(II) complex is observed in the presence of aptamer due to the hydrophobic interaction. Upon addition of PDGF, the luminescence intensity is decreased, due to the stronger interaction between the aptamer and PDGF resulting in the displacement of Ru(II) complex to the aqueous solution. Our assay can detect a target specifically in a complex medium such as the mixture of proteins, at a concentration of 0.8 pM.