Translation of nonclinical to clinical safety findings for 27 biotherapeutics

Human adverse drug reactions (ADRs), and in vivo nonclinical adverse and nonadverse findings, were identified in 27 biotherapeutic programs and placed into organ categories to determine translation. The sensitivity of detecting human ADRs was 30.8% with a positive predictive value (PPV) of 53.3% for nonclinical adverse findings; sensitivity increased to 67.3% and PPV fell to 35.0% when including nonadverse findings. Nonclinical findings were associated with a greater likelihood of a human ADR in that organ category, especially for adverse findings [positive likelihood ratio (LR+) >10 (lower 95% confidence interval [CI] of >5)]. The specificity and negative predictive value (NPV) were very high (>85%). A lack of nonclinical findings in an organ category was associated with a lower likelihood of a human ADR in that organ category. About 40-50% of human ADRs and nonclinical adverse findings, and about 30% of nonclinical nonadverse findings, were attributed to pharmacology. Slightly more than half of the human ADRs with a translating nonclinical finding had findings in animals that could be considered very similar. Overall, 38% of nonclinical findings translated to a human ADR at the organ category level. When nonclinical findings did not translate to humans, the cause was usually higher exposures or longer dosing in animals. All programs with human ADRs attributed to immunogenicity also had nonclinical adverse or nonadverse findings related to immunogenicity. Overall, nonclinical adverse and nonadverse findings were useful in predicting human ADRs, especially at an organ category level, and the majority of human ADRs were predicted by nonclinical toxicity studies.

Multiple Sessions vs. Single Session Image-Based Intracavitary Brachytherapy for Locally Advanced Cervical Cancer: A Randomized Control Trial

PURPOSE/OBJECTIVE(S)

The objectives of this study are: 1) To compare the acute toxicity caused in the treatment of locally advanced cervical cancer (LACC) treated with weekly multiple applications vs. a single application for image-guided intracavitary High Dose Rate (HDR) brachytherapy (BT) after External Beam Radiation Therapy (EBRT) 2) To compare the loco-regional control of cancer at six months in the two arms MATERIALS/METHODS: In a prospective study, 40 patients with biopsy-proven LACC with FIGO-2018 stage IIB-IIIC1 disease, underwent EBRT to the pelvis at a dose of 50.4 Gy/ 28 fractions over 5.5 weeks with weekly concurrent cisplatin. After completion of EBRT, they were randomized into two arms with 20 patients each. In the Control arm (Arm-A), BT sessions were given with weekly 3 applications whereas, in the experimental arm (Arm-B), all the sessions were given with a single application at 6-12 hours intervals with aim of the high-risk clinical target volume receiving >80 Gy EQD2 and 2 cm3 of the bladder and rectum/sigmoid receiving <85 Gy and <75 Gy, respectively. The OAR contouring was done on CT RESULTS: All 40 patients were treated as per protocol. The mean duration of treatment including EBRT and BT was 73.15 days [95% CI 68.63-77.66] in Arm A and 55.85 days [95% CI 52.11-59.58] in Arm B which was significant. After 6 months, 37 patients came for follow-up, all 19 patients in Arm A had Grade 1 or Grade 2 rectal toxicity. In Arm B as well all 18 patients had Grade 1 or Grade 2 rectal toxicity. Bladder toxicity was Grade 1 or Grade 2 in 18 patients and Grade 3 severity in 1 patient among Arm A. Among 18 patients of Arm B, bladder toxicity of Grade 1 or Grade 2 was seen in 16 patients, and 2 patients had grade 3 toxicity. 2 patients in Arm A and 3 in Arm B complained of Grade 1 urinary incontinence. Moreover, Abdominal pain at 6 months was of Grade 1 in around 6 patients in Arm A but 14 patients had abdominal pain in Arm B which was of Grade 1 in 8, 4 had grade 2 and 2 patients had grade 3 severity abdominal pain. In the monthly analysis of acute toxicity, none of the patients showed Grade 3 or 4 toxicity at the 1st, 2nd, or 3rd month of completion of treatment. When comparing local control in both arms at 6 months, 2 patients had treatment failure in the Experimental Arm compared to only 1 patient in the Control Arm CONCLUSION: Single Application Multiple Fraction Intracavitary Brachytherapy post concurrent CTRT is a safe option for the treatment of locally advanced cervical cancer. When compared to the weekly application arm, single-application ICRT showed a comparable acute toxicity profile and comparable local control rates as well. Some patients in Single Application Arm showed abdominal pain which needs to be investigated with further trials. The overall treatment time in the single application arm is significantly lower than the standard weekly application arm.

Fingerprinting heterocellular β-adrenoceptor functional expression in the brain using agonist activity profiles

Noradrenergic projections from the brainstem locus coeruleus drive arousal, attentiveness, mood, and memory, but specific adrenoceptor (AR) function across the varied brain cell types has not been extensively characterized, especially with agonists. This study reports a pharmacological analysis of brain AR function, offering insights for innovative therapeutic interventions that might serve to compensate for locus coeruleus decline, known to develop in the earliest phases of neurodegenerative diseases. First, β-AR agonist activities were measured in recombinant cell systems and compared with those of isoprenaline to generate Δlog(Emax/EC50) values, system-independent metrics of agonist activity, that, in turn, provide receptor subtype fingerprints. These fingerprints were then used to assess receptor subtype expression across human brain cell systems and compared with Δlog(Emax/EC50) values arising from β-arrestin activation or measurements of cAMP response desensitization to assess the possibility of ligand bias among β-AR agonists. Agonist activity profiles were confirmed to be system-independent and, in particular, revealed β2-AR functional expression across several human brain cell types. Broad β2-AR function observed is consistent with noradrenergic tone arising from the locus coeruleus exerting heterocellular neuroexcitatory and homeostatic influence. Notably, Δlog(Emax/EC50) measurements suggest that tested β-AR agonists do not show ligand bias as it pertains to homologous receptor desensitization in the system examined. Δlog(Emax/EC50) agonist fingerprinting is a powerful means of assessing receptor subtype expression regardless of receptor expression levels or assay readout, and the method may be applicable to future use for novel ligands and tissues expressing any receptor with available reference agonists.

Amino Acid Tracer PET MRI in Glioma Management: What a Neuroradiologist Needs to Know

PET with amino acid tracers provides additional insight beyond MR imaging into the biology of gliomas that can be used for initial diagnosis, delineation of tumor margins, planning of surgical and radiation therapy, assessment of residual tumor, and evaluation of posttreatment response. Hybrid PET MR imaging allows the simultaneous acquisition of various PET and MR imaging parameters in a single investigation with reduced scanning time and improved anatomic localization. This review aimed to provide neuroradiologists with a concise overview of the various amino acid tracers and a practical understanding of the clinical applications of amino acid PET MR imaging in glioma management. Future perspectives in newer advances, novel radiotracers, radiomics, and cost-effectiveness are also outlined.

Juvenile toxicity study of PF-07256472/recifercept, a recombinant human soluble fibroblast growth factor receptor 3, in 2-3-month-old cynomolgus monkeys

Achondroplasia is an autosomal disorder caused by point mutation in the gene encoding fibroblast growth factor receptor 3 (FGFR3) and resulting in gain of function. Recifercept is a potential disease modifying treatment for achondroplasia and functions as a decoy protein that competes for ligands of the mutated FGFR3. Recifercept is intended to restore normal bone growth by preventing the mutated FGFR3 from negative inhibitory signaling in pediatric patients with achondroplasia. Here we evaluated the potential effects of twice weekly administration of recifercept to juvenile cynomolgus monkeys (approximately 3-months of age at the initiation of dosing) for 6-months. No adverse effects were noted in this study, identifying the high dose as the no-observed-adverse-effect-level and supporting the use of recifercept in pediatric patients from birth. Considering that juvenile toxicity studies in nonhuman primates are not frequently conducted, and when they are conducted they typically utilize animals ≥9 months of age, this study demonstrates the feasibility of executing a juvenile toxicity study in very young monkeys prior to weaning.

Nonclinical Safety Signals in PharmaPendium Improve the Predictability of Human Drug-Induced Liver Injury

Drug-induced liver injury (DILI) is a leading cause of candidate attrition during drug development in the pharmaceutical industry. This study evaluated liver toxicity signals for 249 approved drugs (114 of "most-DILI concern" and 135 of "no-DILI concern") using PharmaPendium and assessed the association between nonclinical and clinical injuries using contingency table analysis. All animal liver findings were combined into eight toxicity categories based on nature and severity. Together, these analyses revealed that cholestasis [odds ratio (OR): 5.02; 95% confidence interval (CI) 1.04-24.03] or liver aminotransferase increases (OR: 1.86; 95% CI 1.09-3.09) in rats and steatosis (OR-1.9; 95% CI 1.03-3.49) or liver aminotransferase increases (OR-2.57; 95% CI 1.4-4.7) in dogs were significant predictors of human liver injury. The predictive value further improved when the liver injury categories were combined into less severe (steatosis, cholestasis, liver aminotransferase increase, hyperbilirubinemia, or jaundice) and more-severe (liver necrosis, acute liver failure, or hepatotoxicity) injuries. In particular, less-severe liver injuries in the following pairs of species predicted human hepatotoxicity {[dog and mouse] (OR: 2.70; 95% CI 1.25-5.84), [dog and rat] (OR-2.61; 95% CI 1.48-4.59), [monkey and mouse] (OR-4.22; 95% CI 1.33-13.32), and [monkey and rat] (OR-2.45; 95% CI 1.15-5.21)} were predictive of human hepatotoxicity. Meanwhile, severe liver injuries in both [dog and rat] (OR-1.9; 95% CI 1.04-3.49) were significant predictors of human liver toxicity. Therefore, we concluded that the occurrence of DILI in humans is highly likely if liver injuries are observed in one rodent and one nonrodent species and that liver aminotransferase increases in dogs and rats can predict DILI in humans. Together, these findings indicate that the liver safety signals observed in animal toxicity studies indicate potential DILI risk in humans and could therefore be used to prioritize small molecules with less potential to cause DILI in humans.

Differential 18F-NaF uptake in various compartments in knee osteoarthritis: an observational study using PET/MRI

AIM

To investigate if the pattern of fluorine-18-labelled sodium fluoride (¹⁸F-NaF) uptake on integrated positron-emission tomography (PET)/magnetic resonance imaging (MRI) of bone marrow lesions (BML) and osteophytes differs between different knee compartments.

MATERIALS AND METHODS

Sixteen patients with no prior history of knee injury with or without pain were recruited for the study. The images of both knees were acquired on simultaneous PET/MRI. The acquisition was done after 45 minutes of intravenous injection of ¹⁸F-NaF 185-370 MBq (5-10 mCi) for 40 minutes. Each knee was divided into eight compartments patella, trochlea, medial central femur, lateral central femur, medial posterior femur, lateral posterior femur, medial tibia, lateral tibia, and cruciate ligament insertion specifically for BML. BML and osteophytes were scored using MRI Osteoarthritis Knee Score (MOAKS) criteria and their corresponding maximum standardised uptake values (SUVmax) recorded.

RESULTS

BML and osteophytes both showed statistically significant differences among knee compartments, i.e., p-value <0.000 and < 0.043 respectively. SUVmax for BML and osteophytes was greatest in the medial tibia.

CONCLUSION

¹⁸F-NaF PET/MRI showed that BML and osteophytes had differential uptake values due to bone remodelling amongst the various knee compartments and this may help to design disease-modifying osteoarthritis drugs in the future.

Burden of cytokines storm on prognosis of SARS-CoV-2 infection through immune response: dynamic analysis and optimal control with immunomodulatory therapy

Immune responses have a crucial role to play against SARS-CoV-2 virus as the adaptive and innate immune systems of the human body help restoring the body to a healthy stage by annihilating this deadly viral infection. Cytokines also play a significant role in modulating a balance between innate and adaptive immune responses but excess of it can have a detrimental affect on critically ill patients. Therefore, this paper is a novel attempt to formulate a within-host mathematical model showing the impact of cytokines storm on healthy cells. The dynamics of the system is analysed which involves basic reproduction number, steady state solutions and global dynamics for disease-free point and endemic equilibrium using geometric approach. Further, an optimal control problem is discussed considering immunomodulatory therapy (targeting cytokines signaling) as control using linear feedback control method to increase the level of healthy cells, which provides vitality for our system. Through numerical simulations, analytic solutions are validated followed by the curve-fit for the cytokines using real data and an optimization algorithm for optimal fit. Finally, sensitivity analysis for the basic reproduction number and the rate of change of healthy cells using Latin Hypercube Sampling method (LHS) is performed. Our finding suggests that immunomodulatory therapy (tocilizumab) can act as a key component to control cytokines storm for critically ill patients to restore the body to a healthy state.

Hepatotoxicity reports in the FDA adverse event reporting system database: A comparison of drugs that cause injury via mitochondrial or other mechanisms

Drug-induced liver injury (DILI) is a leading reason for preclinical safety attrition and post-market drug withdrawals. Drug-induced mitochondrial toxicity has been shown to play an essential role in various forms of DILI, especially in idiosyncratic liver injury. This study examined liver injury reports submitted to the Food and Drug Administration (FDA) Adverse Event Reporting System (FAERS) for drugs associated with hepatotoxicity via mitochondrial mechanisms compared with non-mitochondrial mechanisms of toxicity. The frequency of hepatotoxicity was determined at a group level and individual drug level. A reporting odds ratio (ROR) was calculated as the measure of effect. Between the two DILI groups, reports for DILI involving mitochondrial mechanisms of toxicity had a 1.43 (95% CI 1.42-1.45; P < 0.0001) times higher odds compared to drugs associated with non-mitochondrial mechanisms of toxicity. Antineoplastic, antiviral, analgesic, antibiotic, and antimycobacterial drugs were the top five drug classes with the highest ROR values. Although the top 20 drugs with the highest ROR values included drugs with both mitochondrial and non-mitochondrial injury mechanisms, the top four drugs (ROR values > 18: benzbromarone, troglitazone, isoniazid, rifampin) were associated with mitochondrial mechanisms of toxicity. The major demographic influence for DILI risk was also examined. There was a higher mean patient age among reports for drugs that were associated with mitochondrial mechanisms of toxicity [56.1 ± 18.33 (SD)] compared to non-mitochondrial mechanisms [48 ± 19.53 (SD)] (P < 0.0001), suggesting that age may play a role in susceptibility to DILI via mitochondrial mechanisms of toxicity. Univariate logistic regression analysis showed that reports of liver injury were 2.2 (odds ratio: 2.2, 95% CI 2.12-2.26) times more likely to be associated with older patient age, as compared with reports involving patients less than 65 years of age. Compared to males, female patients were 37% less likely (odds ratio: 0.63, 95% CI 0.61-0.64) to be subjects of liver injury reports for drugs associated with mitochondrial toxicity mechanisms. Given the higher proportion of severe liver injury reports among drugs associated with mitochondrial mechanisms of toxicity, it is essential to understand if a drug causes mitochondrial toxicity during preclinical drug development when drug design alternatives, more clinically relevant animal models, and better clinical biomarkers may provide a better translation of drug-induced mitochondrial toxicity risk assessment from animals to humans. Our findings from this study align with mitochondrial mechanisms of toxicity being an important cause of DILI, and this should be further investigated in real-world studies with robust designs.

Most Influential Physicochemical and In Vitro Assay Descriptors for Hepatotoxicity and Nephrotoxicity Prediction

Drug-induced organ injury is a major reason for drug candidate attrition in preclinical and clinical drug development. The liver, kidneys, and heart have been recognized as the most common organ systems affected in safety-related attrition or the subject of black box warnings and postmarket drug withdrawals. In silico physicochemical property calculations and in vitro assays have been utilized separately in the early stages of the drug discovery and development process to predict drug safety. In this study, we combined physicochemical properties and in vitro cytotoxicity assays including mitochondrial dysfunction to build organ-specific univariate and multivariable logistic regression models to achieve odds ratios for the prediction of clinical hepatotoxicity, nephrotoxicity, and cardiotoxicity using 215 marketed drugs. The multivariable hepatotoxic predictive model showed an odds ratio of 6.2 (95% confidence interval (CI) 1.7-22.8) or 7.5 (95% CI 3.2-17.8) for mitochondrial inhibition or drug plasma C_max >1 μM for drugs associated with liver injury, respectively. The multivariable nephrotoxicity predictive model showed an odds ratio of 5.8 (95% CI 2.0-16.9), 6.4 (95% CI 1.1-39.3), or 15.9 (95% CI 2.8-89.0) for drug plasma C_max >1 μM, mitochondrial inhibition, or hydrogen-bond-acceptor atoms >7 for drugs associated with kidney injury, respectively. Conversely, drugs with a total polar surface area ≥75 Å were 79% (odds ratio 0.21, 95% CI 0.061-0.74) less likely to be associated with kidney injury. Drugs belonging to the extended clearance classification system (ECCS) class 4, where renal secretion is the primary clearance mechanism (low permeability drugs that are bases/neutrals), were 4 (95% CI 1.8-9.5) times more likely to to be associated with kidney injury with this data set. Alternatively, ECCS class 2 drugs, where hepatic metabolism is the primary clearance (high permeability drugs that are bases/neutrals) were 77% less likely (odds ratio 0.23 95% CI 0.095-0.54) to to be associated with kidney injury. A cardiotoxicity model was poorly defined using any of these drug physicochemical attributes. Combining in silico physicochemical properties descriptors along with in vitro toxicity assays can be used to build predictive toxicity models to select small molecule therapeutics with less potential to cause liver and kidney organ toxicity.

Abstract 4441: Discovery of potent and selective inhibitors of USP7 with anti-tumor activity in vitro and in vivo

USP7 is a deubiquitinase that regulates the levels of multiple downstream targets with roles in cancer progression and immune response. Inhibitors of USP7 may thus decrease oncogene function, increase tumor suppressor function, enhance immune function and sensitize tumor cells to DNA damaging agents. We have discovered a novel chemical series that potently and selectively inhibits USP7 in biochemical and cellular assays. Our inhibitors reduce the viability of multiple p53-wild type cell lines, including several blood cancer and MYCN-amplified neuroblastoma cell lines, as well as a subset of p53-mutant tumor cell lines in vitro. Further, oral administration of our USP7 inhibitors inhibits MM.1S (multiple myeloma; p53-wild type) and H526 (small cell lung cancer; p53-mutant) tumor growth in vivo. Our work confirms that USP7 is a pharmacologically tractable target and future studies will aim to further understand the mechanism of action of USP7 inhibitors in p53-mutant cancers.

Citation Format: Yamini M. Ohol, Michael Sun, Paul Leger, Dennis Hu, Berenger Biannic, Payal Rana, Cynthia Cho, Scott Jacobson, Steve Wong, Jerick Sanchez, Xinping Han, Kyle Young, Akinori Okano, Jack Maung, Gene Cutler, Nick Shah, Lavanya Adusumilli, Deepika Kaveri, Oezcan Talay, Deepa Pookot, Betty Abraham, Delia Bradford, Nathan Kozon, Christophe Colas, Andrea Kim, Jacob Schwarz, David Wustrow, Dirk Brockstedt, Paul Kassner. Discovery of potent and selective inhibitors of USP7 with anti-tumor activity in vitro and in vivo [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 4441.

Abstract 2915: Discovery and optimization of potent and selective inhibitors of USP7 to enhance anti-tumor immunity and target tumor growth

USP7 is a deubiquitinase (DUB) that has attracted much attention recently due to its multiple roles in promoting cancer progression. By removal of ubiquitin from protein substrates, USP7 stabilizes oncogenes such as MDM2 and Myc, destabilizes and inactivates the key tumor suppressors p53 and PTEN, and imparts resistance to DNA-damaging chemotherapy by enhancing DNA repair responses. USP7 plays an important role in suppression of immune responses in the tumor microenvironment by stabilizing the transcription factor FOXP3 and thereby enhancing the suppressive function of regulatory T cells. Thus, inhibition of USP7 is an appealing therapeutic strategy because it has the potential to impact important oncology targets such as transcription factors that have been widely viewed as undruggable. We employed structure-based and other medicinal chemistry techniques to enable the design of potent and selective USP7 inhibitors. Using a high-throughput assay of DUB activity employing rhodamine-labeled ubiquitin, we optimized several series of reversible USP7 inhibitors to sub-100 pM potency and selectivity of &gt;10,000-fold over all other DUBs. Cellular activity was demonstrated using a luciferase reporter gene assay of p53 activation, revealing compounds with EC50 values ranging down to 20 nM. To assess the role of USP7 inhibition in enhancement of immune responses, we determined relief of suppression of effector T cells in vitro. Effector T cells (CD8+) were co-cultured with regulatory T cells (CD4+ FOXP3+) and antigen-presenting cells for 4 days, after which CD8+ cell proliferation was determined by flow cytometry. Treatment with USP7 inhibitors during co-culture resulted in relief of regulatory T cell suppression of CD8+ cell proliferation. In vivo enhancement of immune responses was assessed in rodent models of inflammation and tumor growth. Direct effects on tumor cell growth and viability were explored by profiling cytotoxicity of USP7 inhibitors as single agents and in combination with chemotherapeutic agents in a broad range of cancer cell lines. In preparation for future clinical development, compounds were modified to obtain desirable in vitro and in vivo ADME and toxicity profiles. Following extensive pre-clinical optimization, we have in hand orally bioavailable compounds with high permeability, low clearance, and minimal off-target activity.

Citation Format: Betty Abraham, Lavanya Adusumilli, Berenger Biannic, Delia Bradford, Martin Brovarney, David Chian, Gene Cutler, Xinping Han, Dennis Hu, Scott Jacobson, Sherra Johnson, Paul Kassner, Deepika Kaveri, John Ketcham, Andrea Kim, Paul Leger, Lisa Marshall, Sachie Marubayashi, Jack Maung, Jenny McKinnell, Cesar Meleza, Yamini Ohol, Akinori Okano, Leanne Peiser, Deepa Pookot, Payal Rana, Jacob Schwarz, Nick Shah, Grant Shibuya, Michael Sun, Silpa Suthram, Oezcan Talay, Angela Wadsworth, David Wustrow, Kyle Young, Andrew Napper. Discovery and optimization of potent and selective inhibitors of USP7 to enhance anti-tumor immunity and target tumor growth [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 2915.

Prediction of metabolism-induced hepatotoxicity on three-dimensional hepatic cell culture and enzyme microarrays

Human liver contains various oxidative and conjugative enzymes that can convert nontoxic parent compounds to toxic metabolites or, conversely, toxic parent compounds to nontoxic metabolites. Unlike primary hepatocytes, which contain myriad drug-metabolizing enzymes (DMEs), but are difficult to culture and maintain physiological levels of DMEs, immortalized hepatic cell lines used in predictive toxicity assays are easy to culture, but lack the ability to metabolize compounds. To address this limitation and predict metabolism-induced hepatotoxicity in high-throughput, we developed an advanced miniaturized three-dimensional (3D) cell culture array (DataChip 2.0) and an advanced metabolizing enzyme microarray (MetaChip 2.0). The DataChip is a functionalized micropillar chip that supports the Hep3B human hepatoma cell line in a 3D microarray format. The MetaChip is a microwell chip containing immobilized DMEs found in the human liver. As a proof of concept for generating compound metabolites in situ on the chip and rapidly assessing their toxicity, 22 model compounds were dispensed into the MetaChip and sandwiched with the DataChip. The IC₅₀ values obtained from the chip platform were correlated with rat LD₅₀ values, human C _max values, and drug-induced liver injury categories to predict adverse drug reactions in vivo. As a result, the platform had 100% sensitivity, 86% specificity, and 93% overall predictivity at optimum cutoffs of IC₅₀ and C _max values. Therefore, the DataChip/MetaChip platform could be used as a high-throughput, early stage, microscale alternative to conventional in vitro multi-well plate platforms and provide a rapid and inexpensive assessment of metabolism-induced toxicity at early phases of drug development.

Utilization of iPSC-derived human neurons for high-throughput drug-induced peripheral neuropathy screening

As the number of cancer survivors continues to grow, awareness of long-term toxicities and impact on quality of life after chemotherapy treatment in cancer survivors has intensified. Chemotherapy-induced peripheral neuropathy (CIPN) is one of the most common side effects of modern chemotherapy. Animal models are used to study peripheral neuropathy and predict human risk; however, such models are labor-intensive and limited translatability between species has become a major challenge. Moreover, the mechanisms underlying CIPN have not been precisely determined and few human neuronal models to study CIPN exist. Here, we have developed a high-throughput drug-induced neurotoxicity screening model using human iPSC-derived peripheral-like neurons to study the effect of chemotherapy agents on neuronal health and morphology using high content imaging measurements (neurite length and neuronal cell viability). We utilized this model to test various classes of chemotherapeutic agents with known clinical liability to cause peripheral neuropathy such as platinum agents, taxanes, vinca alkaloids, proteasome inhibitors, and anti-angiogenic compounds. The model was sensitive to compounds that cause interference in microtubule dynamics, especially the taxane, epothilone, and vinca alkaloids. Conversely, the model was not sensitive to platinum and anti-angiogenic chemotherapeutics; compounds that are not reported to act directly on neuronal processes. In summary, we believe this model has utility for high-throughput screening and prediction of human risk for CIPN for novel chemotherapeutics.

Abstract P4-19-02: Young women with early stage breast cancer and their supportive care needs: Results from a regional survey

Background

Approximately 18% of all newly diagnosed breast cancer cases in Canada occur in women less than 50 years of age. Young women with breast cancer (YWBC) may experience unique physical and psycho-social issues yet there is a lack of data outlining their specific needs and concerns across the trajectory of care. This study described the unmet supportive care needs of YWBC at a regional cancer centre in southern Ontario, Canada.

Objectives

1. To describe unmet supportive care needs of young women (&lt;45 years) with early stage breast cancer in a representative region by using the Supportive Cancer Needs Survey (SCNS-SF34).

2. To describe the level of satisfaction with information to support cancer treatment decision making and causes of distress among YWBC (&lt;45 years) in a representative region.

Study Design

This study used a prospective survey design that was administered to consenting YWBC. The Supportive Care Needs Survey (SCNS-SF34) was used to measure respondents' need for cancer support and care. This instrument captures needs through 34-items that cover five domains: psychological needs, health system and informational needs, physical and daily living needs, patient care support needs and sexuality needs. In addition, an original 26-item survey questionnaire was administered. Survey items were developed from the recurring themes of an earlier project that informed 4 levels of inquiry: demographics, decision making/ informational support, disease and treatment characteristics, and causes of distress.

Results

Fifty-one patients were approached by a member of their circle of care. Of these patients, 35 completed the survey resulting in a 69% response rate. The majority of respondents were between the ages of 33 and 40 (48.6%), were diagnosed within 6 to 12 months of study entry (60.0%); had a university degree (51.4%); were married (82.9%) and (65.7%) have young children.

The three most common Moderate to High Unmet Supportive Care needs (rated 4 or 5 on a 5-point Likert scale) were: “Worries of those close to you” (34.3%), “Fears about the cancer spreading” (34.3%), “Anxiety” (28.6%) all of which reside in the psychological domain. Overall respondents agreed or strongly agreed to statements regarding their level of satisfaction with information to support cancer treatment decision making provided by their oncology team. Respondents did score lower in satisfaction with the information their oncology team provided regarding fertility. In terms of psychosocial support, 40% percent of respondents reported they had met with a social worker and 17% reported attending a breast cancer support group.

Conclusion

The results highlight that the supportive care needs of many YWBC are unmet, particularly those related to psychological burden and fertility concerns. Early identification and appropriate referral to fertility specialists and/or supportive care social workers could improve current practice. Further research is needed to explore how barriers to fertility and supportive care needs of young adults with cancer may best be overcome.

Citation Format: Ratcliffe J, Hodgson N, Rana P, Forbes M, Levine M, Sussman J. Young women with early stage breast cancer and their supportive care needs: Results from a regional survey [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P4-19-02.

Hippocampal Neurometabolite Changes in Hypothyroidism: An In Vivo (1) H Magnetic Resonance Spectroscopy Study Before and After Thyroxine Treatment

The hippocampus is a thyroid hormone receptor-rich region of the brain. A change in thyroid hormone levels may be responsible for an alteration in hippocampal-associated function, such as learning, memory and attention. Neuroimaging studies have shown functional and structural changes in the hippocampus as a result of hypothyroidism. However, the underlying process responsible for this dysfunction remains unclear. Therefore, the present study aimed to investigate the metabolic changes in the brain of adult hypothyroid patients during pre- and post-thyroxine treatment using in vivo proton magnetic resonance spectroscopy ((1) H MRS). (1) H MRS was performed in both healthy control subjects (n = 15) and hypothyroid patients (n = 15) (before and after thyroxine treatment). The relative ratios of the neurometabolites were calculated using the linear combination model (LCModel). Our results revealed a significant decrease of glutamate (Glu) (P = 0.045) and myo-inositol (mI) (P = 0.002) levels in the hippocampus of hypothyroid patients compared to controls. No significant changes in metabolite ratios were observed in the hypothyroid patients after thyroxine treatment. The findings of the present study reveal decreased Glu/tCr and mI/tCr ratios in the hippocampus of hypothyroid patients and these metabolite alterations persisted even after the patients became clinically euthyroid subsequent to thyroxine treatment.

Development of a cell viability assay to assess drug metabolite structure-toxicity relationships

Many adverse drug reactions are caused by the cytochrome P450 (CYP)-dependent activation of drugs into reactive metabolites. In order to reduce attrition due to metabolism-induced toxicity and to improve the safety of drug candidates, we developed a simple cell viability assay by combining a bioactivation system (human CYP3A4, CYP2D6 and CYP2C9) with Hep3B cells. We screened a series of drugs to explore structural motifs that may be responsible for CYP450-dependent activation caused by reactive metabolite formation, which highlighted specific liabilities regarding certain phenols and anilines.

Demyelinating evidences in CMS rat model of depression: a DTI study at 7 T

Depression is among the most debilitating diseases worldwide. Long-term exposure to stressors plays a major role in development of human depression. Chronic mild stress (CMS) seems to be a valid animal model for depression. Diffusion tensor imaging (DTI) is capable of inferring microstructural abnormalities of the white matter and has shown to serve as non-invasive marker of specific pathology. We developed a CMS rat model of depression and validated with behavioral experiments. We measured the diffusion indices (mean diffusivity (MD), fractional anisotropy (FA), axial (λ∥) and radial (λ⊥) diffusivity) to investigate the changes in CMS rat brain during depression onset. Diffusion indices have shown to be useful to discriminate myelin damage from axon loss. DTI was performed in both control and CMS rats (n=10, in each group) and maps of FA, MD, λ∥ and λ⊥ diffusivity values were generated using in-house built software. The diffusion indices were calculated by region of interest (ROI) analysis in different brain regions like the frontal cortex, hippocampus, hypothalamus, cingulum, thalamus, caudate putamen, corpus callosum, cerebral peduncle and sensory motor cortex. The results showed signs of demyelination, reflected by increased MD, decreased FA and increased λ⊥. The results also suggest a possible role of edema or inflammation concerning the brain morphology in CMS rats. The overall finding using DTI suggests there might be a major role of loss of myelin sheath, which leads to disrupted connectivity between the limbic area and the prefrontal cortex during the onset of depression. Our findings indicate that interpretation of these indices may provide crucial information about the type and severity of mood disorders.

Characterization of human-induced pluripotent stem cell-derived cardiomyocytes: bioenergetics and utilization in safety screening

Cardiotoxicity remains the number one reason for drug withdrawal from the market, and Food and Drug Administration issued black box warnings, thus demonstrating the need for more predictive preclinical safety screening, especially early in the drug discovery process when much chemical substrate is available. Whereas human-ether-a-go-go related gene screening has become routine to mitigate proarrhythmic risk, the development of in vitro assays predicting additional on- and off-target biochemical toxicities will benefit from cellular models exhibiting true cardiomyocyte characteristics such as native tissue-like mitochondrial activity. Human stem cell-derived tissue cells may provide such a model. This hypothesis was tested using a combination of flux analysis, gene and protein expression, and toxicity-profiling techniques to characterize mitochondrial function in induced pluripotent stem cell (iPSC) derived human cardiomyocytes in the presence of differing carbon sources over extended periods in cell culture. Functional analyses demonstrate that iPSC-derived cardiomyocytes are (1) capable of utilizing anaerobic or aerobic respiration depending upon the available carbon substrate and (2) bioenergetically closest to adult heart tissue cells when cultured in galactose or galactose supplemented with fatty acids. We utilized this model to test a variety of kinase inhibitors with known clinical cardiac liabilities for their potential toxicity toward these cells. We found that the kinase inhibitors showed a dose-dependent toxicity to iPSC cardiomyocytes grown in galactose and that oxygen consumption rates were significantly more affected than adenosine triphosphate production. Sorafenib was found to have the most effect, followed by sunitinib, dasatinib, imatinib, lapatinib, and nioltinib.

Palmitate increases the susceptibility of cells to drug-induced toxicity: an in vitro method to identify drugs with potential contraindications in patients with metabolic disease

Fatty acids are an important source of energy. Excessive energy intake results in elevated levels of free fatty acids that are thought to be the pathogenic factors causing metabolic disorders such as dyslipidemia, obesity, insulin resistance, diabetes, and fatty liver. Underlying metabolic disorders have been suggested to be a predisposing factor for drug-induced liver injury. The steadily expanding population with metabolic disease may pose a higher risk for drug-induced toxicity. In order to understand the interaction of free fatty acids and drug-induced toxicity at the cellular level, we explored whether the saturated free fatty acid palmitate could modulate drug-induced cytotoxicity in HepG2 cells. A number of drugs known to induce hepatotoxicity in humans were selected to test this hypothesis. Drugs without reported hepatotoxicity were also tested to evaluate the specificity of the palmitate-induced effects. We demonstrate that palmitate, at sublethal concentrations, was able to potentiate the cytotoxicity and/or apoptosis induced by some but not all drugs tested. The palmitate and drug coincubation potentiated toxicity, which when combined with the plasma maximum concentration (C(max)), allowed us to identify idiosyncratic toxic drugs that were not flagged in previously deployed cytotoxicity assays. Our data suggest that treatment of cells with palmitate improves the sensitivity to detect compounds with risk of inducing idiosyncratic liver toxicity. Furthermore, this assay may be used to identify compounds that have higher safety risks in a population with metabolic syndrome.

Profiling of toxicity and identification of distinct apoptosis profiles using a 384-well high-throughput flow cytometry screening platform

Methods and techniques used to detect apoptosis have benefited from advances in technologies such as flow cytometry. With a large arsenal of lasers, fluorescent labels, and readily accessible biological targets, it is possible to detect multiple targets with unique combinations of fluorescent spectral signatures from a single sample. Traditional flow cytometry has been limited as a screening tool as the sample throughput has been low, whereas the data analysis and generation of screening relevant results have been complex. The HTFC Screening System running ForeCyt software is an instrument platform designed to perform high-throughput, multiplexed screening with seamless transformation of flow cytometry data into screening hits. We report the results of a screen that simultaneously quantified caspase 3/7 activation, annexin V binding, cell viability, and mitochondrial integrity. Assay performance over 5 days demonstrated robustness, reliability, and performance of the assay. This system is high throughput in that a 384-well plate can be read and fully analyzed within 30 min and is sensitive with an assay window of at least 10-fold for all parameters and a Z' factor of ≥0.75 for all endpoints and time points. From a screen of 231 compounds, 11 representative toxicity profiles highlighting differential activation of apoptotic pathways were identified.

Phosphorous magnetic resonance spectroscopy-based skeletal muscle bioenergetic studies in subclinical hypothyroidism

BACKGROUND

Subclinical hypothyroidism (sHT) is considered to be a milder form of thyroid dysfunction. Few earlier studies have reported neuromuscular symptoms as well as impaired muscle metabolism in sHT patients.

AIM/OBJECTIVE

In this study we report our findings on muscle bioenergetics in sHT patients using phosphorous magnetic resonance spectroscopy (31P MRS) and look upon the possibility to use 31P MRS technique as a clinical marker for monitoring muscle function in subclinical thyroid dysfunction.

SUBJECTS AND METHODS

Seventeen normal subjects, 15 patients with sHT, and 9 patients with hypothyroidism performed plantar flexion exercise while lying supine in 1.5 T magnetic resonance scanner using custom built exercise device. MR Spectroscopy measurements of inorganic phosphate (Pi), phosphocreatine (PCr), and ATP of the calf muscle were taken during rest, at the end of exercise and in the recovery phase. PCr recovery rate constant (kPCr) and oxidative capacity were calculated by monoexponential fit of PCr vs time (t) at the beginning of recovery.

RESULTS

We observed that changes in some of the phosphometabolites (increased phosphodiester levels and Pi concentration) in sHT patients which were similar to those detected in patients with hypothyroidism. However, our results do not demonstrate impaired muscle oxidative metabolism in sHT patients based upon PCr dynamics as observed in hypothyroid patients.

CONCLUSIONS

31P MRS-based PCr recovery rate could be used as a marker for monitoring muscle oxidative metabolism in sub clinical thyroid dysfunction.

Study of semiconducting nanomaterials under pressure

The pressure induced structural and mechanical properties of nanocrystalline ZnO, ZnS, ZnSe, GaN, CoO, CdSe, CeO(2), SnO(2), SiC, c-BC(2)N, and β-Ga(2)O(3) with different grain sizes have been analyzed under high pressures. The molecular dynamics simulation model has been used to compute isothermal equation of state, volume collapse and bulk modulus of these materials in nano and bulk phases at ambient and high pressures and compared with the experimental data. It is evident from these calculations that the change in particle size affects directly the phase transition pressure and bulk modulus. The values of phase transition pressure and bulk modulus increase with decrease in grain size of the material. The equilibrium cell volume and volume collapse in parent phase is directly proportional to the grain size of the materials. Present results are in good agreement with experimental data. The model is able to explain these thermodynamic properties at varying temperatures and pressures successfully.

Incidentally detected squamous cell carcinoma in non-functioning kidney presenting as multi-cystic mass

Squamous cell carcinoma (SCC) of urinary tract is a rarely encountered tumor. The incidence of this tumor is 1.4 per cent of all renal malignancies (1). We present a case of 52 years male with squamous cell carcinoma of renal pelvis, presenting as chronic pyelonephritis transforming the kidney into non-functioning multicystic cavitatory mass without any renal calculi. The case highlights the rarity of tumor in absence of calculi or any other predisposing factor. Moreover, histology of resected specimen detected features of SCC giving importance to careful and exhaustive assessment of specimen and of histologic sections, when there is no suspicion of malignancy clinically.

Mitochondrial membrane potential measurement of H9c2 cells grown in high-glucose and galactose-containing media does not provide additional predictivity towards mitochondrial assessment

Drug-induced mitochondrial toxicity is a contributing factor to many organ toxicities. The fact that some, but not all members of a particular drug class can induce mitochondrial dysfunction has necessitated the need for predictive screens within the drug development process. One of these screens is a cell viability assay done in two types of media, one containing high-glucose, the other, galactose. Since galactose-grown cells are more susceptible to mitochondrial toxicants than high-glucose-grown cells, this assay distinguishes compounds that cause toxicity primarily through mitochondrial targets from those that cause multifactorial toxicity. However, the assay does not show if compounds that cause multifactorial toxicity cause impairment on mitochondria. To address this problem, we investigated if multiplexing the assay with mitochondrial membrane potential measurements using the fluorescent dye, JC-1, could provide further information. We tested 28 drugs in the multiplexed assay and found that, although mitochondrial toxicants could be detected, no additional information was revealed about compounds that caused multifactorial toxicity. Hence, measurements with JC-1 did not provide additional information beyond what was detected using the cell viability assay. We conclude that even though the multiplexed assay is useful for HTS applications, it provides no additional value over the high-glucose-galactose cell viability assay.

Analysis of pharmacogenetic biomarkers in rectal patients trated with chemoradiotherapy

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Background: 5FU-based chemoradiotherapy before total mesorectal excision (TME) is currently the gold standard treatment for stage II and III rectal cancer patients. Pathological complete response (pCR) is related with a longer survival. We have used known predictive pharmacogenetics biomarkers to identify in our series responders and non responders to preoperative RQ. Methods: 77 stage II/III rectal patients were genotyped using direct sequencing (TS VNTR) and SNAPshot (DPYD, EGFR) techniques. DNA was obtained from peripheral blood samples. We have studied Thymidylate synthetase (TS VNTR; high expression haplotypes: TSER 2R/3R, 3C/3G, 3G/3G and low expression: TSER 2R/2R, 2R/3C, 3C/3C; TS 1494del6: associated to a better efficay of 5Fu), dihydropyrimidine dehydrogenase (DPYD; DPYD*2 associated to worse toxicity), EGFR (CA repeats in intron 1: 16/16 associated to worse efficacy) polymorphisms. Median age of our study cohort was 65 years old (37–85). There were 24 female and 53 male patients. All of them were Caucasian. 21 patients (27.3%) had stage II and 56 (72.7%) stage III. They were staged by TC, colonoscopy and endorectal ultrasonography. The patients received 5fu 325 mg/m2/day continuous infusion along the hyperfractionated accelerated radiotherapy schedule (50,4 Gy). All were submitted to TME. Outcomes after surgery are measured by tumour regression grade (from TRG1= complete pathological response, to TRG5=no regression). Data were studied by univariate and multivariate analysis. Results: The sample was in Hardy-Weinberg equilibrium for all polymorphisms, irrespectively of the response status. 50 patients (64.9%) and 27 (35.1%) had low and high expression genotype for TS respectively. pCR (TRG1) was obtained in 24 patients (31,6%) and microscopic foci (TRG2) in 14 (18,2%), TRG 3–4 in 38 (49,3%), and 1 patient had no response (TRG5). We haven’t found a statistically significant relationship between TRG1 and TS status, or any other biomarker studied. There's no relationship also with initial clinical stage. Conclusions: Biomarkers EGFR (intron 1 CA repeats), TS (TS 1494del6, TS VNTR) and DPYD in blood samples, are not good enough to predict response to RQ in rectal cancer.

No significant financial relationships to disclose.

Antioxidant potential of thyme extract: alleviation of N-nitrosodiethylamine-induced oxidative stress

Protective role of thyme extract against N-nitrosodiethylamine (NDEA)-induced oxidative stress has been evaluated in albino rats. For this, one group of rats were fed diet supplemented with thyme extract (0.5%) and served as the test group, whereas animals of the other group fed on normal diet served as the control group. The rats were fed on respective diets for a period of 2 weeks after which stress was induced to half the animals of each group by i.p. administration of NDEA at 200 mg/kg body weight. Animals were killed 48 h post stress-induction period. Feed intake and body weight decreased significantly in both test and control groups, the effect being less in test group. Increase in osmotic fragility and in-vitro lipid peroxidation (LPO) on stress induction was of lower degree in the test group. NDEA toxicity was mainly reflected in liver as evidenced by increased activities of plasma aspartate aminotransferase, alanine aminotransferase, and alkaline phosphatase. The effect was of lower degree in test group as compared with that in the control group. Increase in urea levels observed following NDEA administration was also of lower degree in test groups. Blood glutathione (GSH) levels increased more so in test group compared with control group on stress induction. The activities of superoxide dismutase (SOD), peroxidase (Px), and catalase (CAT) activities decreased significantly on stress induction in erythrocytes. LPO increased in all the tissues through varying degree, and the increase was appreciably of lower degree in test group. The activity of SOD increased significantly in both test and control group on stress induction, whereas activities of Px and CAT decreased following NDEA treatment, and the effects were of lower degree in test group. Thus, supplementation of diet with thyme extract can improve antioxygenic potential and hence help to prevent oxidative stress.

Electrochemical removal of chromium from wastewater by using carbon aerogel electrodes

A study has been carried out to determine the feasibility of electrochemical removal of chromium ions from industrial wastewater using carbon aerogel electrodes. In this work the effect of key variables including pH (2-7), concentration 2-8 (mg/l), and charge 0.3-1.3 (A h) was determined. The metal ion removal was significantly increased at reduced pH and high charge conditions. The metal concentration in the wastewater can be reduced by 98.5% under high charge (0.8A h) and acidic conditions (pH 2). The effect of the independent parameters--pH, effluent concentration and charge on the percentage removal was depicted by a quadratic equation obtained using Box-Behnken model. The regression analysis gave a R2 value of 0.9469 shows a close fit between the experimental results and the model predictions. The model was further used to optimise the parameters to maximise the percentage Cr-removal to more than 98%.