We are engaged in the setup of new innovative cancer preclinical models with high predictive values in order to test new therapies or new combinations of current therapies. Recently our work has focused on a highly lethal cancer pathology, Glioblastoma Multiforme (GBM).
Treating people with schizophrenia still represents a major challenge for neuropsychiatric drug development companies. While available atypical antipsychotics are mainly effective on positive symptoms of schizophrenia, their effects on cognitive and social-cognitive deficits remain insufficient and poorly characterized. For instance, a modest improvement of cognitive functions has been described following clozapine treatment. Nevertheless, it remains unclear whether this outcome is due to a direct effect on the neural circuits underlying cognition or to an indirect effect mediated by an overall reduction in positive symptoms. To address this question, we sought to measure mismatch negativity (MMN) responses in telemetered rats. MMN constitutes an electroencephalography-based biomarker of sensory, pre-attentional and predictive coding processes, functions whose disruptions highly influence certain aspects of patients’ cognitive symptoms. MMN was measured under N-methyl-D-aspartate receptor (NMDAr) pharmacological inhibition by MK-801 (dizocilpine), a model based on the glutamatergic hypothesis of schizophrenia, and we tested whether clozapine could improve MMN under this condition or not. We found that MK-801 dose-dependently reduced the MMN peak amplitude in rats, aligning with the MMN response deficit seen in schizophrenia patients. Strikingly, clozapine was able to mitigate this electrophysiological deficit, an unprecedented observation that has the potential to inspire new treatment strategies aimed towards unaddressed schizophrenia symptoms.
Genetic characterization of cell lines is essential for understanding and predicting sensitivity to anti-tumoral targeted therapies. A panel of genetically characterized cell lines from rare tumors (mucosal melanomas, histiocytic sarcomas, osteosarcomas, gliomas…) has been developed to test novel and repositioned anti-tumor therapies, focusing on mucosal melanoma (MM) models.
Ketamir-2 is a newly developed molecular entity designed to overcome key limitations of ketamine by improving oral bioavailability and minimizing side effects such as dissociation and hyperlocomotion. Developed by Mira Pharmaceuticals with preclinical support from Pharmaseed and Biotrial, this compound is a low-affinity, highly selective NMDA receptor antagonist that binds specifically to the PCP site, without interacting with other receptor systems.
Unlike ketamine, which influences multiple targets (e.g., opioid, serotonin, dopamine systems), Ketamir-2 shows minimal off-target activity, suggesting a cleaner pharmacological profile. Behavioral testing in mice (Open Field Test, Elevated Plus Maze, and Forced Swim Test) revealed promising anxiolytic and antidepressant-like effects—without the stimulant effects typically observed with ketamine.
This comprehensive review summarizes the evolution and advancements in the nonclinical assessment of drug-induced QT interval prolongation and associated cardiac risks. It discusses the impact of regulatory guidelines such as ICH S7B and E14 on shaping safety testing strategies and highlights innovative in vitro, in vivo, and computational models that have improved the prediction of proarrhythmic potential. Emphasizing the integration of nonclinical and clinical data, the review also addresses the adoption of new methodologies and ethical principles that are driving safer and more efficient drug development.
The ICH E14/S7B Q&As highlighted the need for best practices concerning the design, execution, analysis, interpretation, and reporting of the in vivo non-rodent QT assay as a component of the integrated risk assessment to potentially support a TQT waiver or substitute. We conducted a dog telemetry study to assess the effects on QTc of six reference compounds (five positive and one negative) previously evaluated by Darpo et al. (2015) in humans. The sensitivity of the assay to detect QTc increases was determined, and exposure–response analysis was performed, as done in clinical practice. By-timepoint analysis showed QTc prolongation induced by moxifloxacin, dofetilide, dolasetron, ondansetron, and quinine within human relevant plasma exposures ranges. Moreover, a hysteresis was observed for quinine. As expected, levocetirizine showed no statistically significant effect on QTc across a range of exposure, well exceeding the therapeutic Cmax. Power analyses confirmed the study ability to detect statistically significant QTc changes of less than 10 milliseconds with 80% probability, even with a sample size as low as n = 4 animals. Finally, concentration-QTc modeling enabled to predict the minimal plasma concentration needed to detect a 10 milliseconds QTc prolongation, including for quinine. The comparison with clinical available data supported the relevance of dogs under these experimental conditions as a robust translational predictor of drug-induced QTc prolongation in humans as a key pillar of the integrated risk assessment.
In cancer research, murine models play a crucial role as highly valuable preclinical tools. Here, we present a protocol to generate a murine model of glioblastoma through the direct intracranial injection of tumor cells. We describe steps for cell culture, intracranial implantation, and standard-of-care treatments. We then detail procedures for monitoring tumor growth using bioluminescent imaging.
Lung cancer is one of the most common and deadliest cancers. Preclinical models are essential to study new therapies and combinations taking tumor genetics into account. We have established cell lines expressing the luciferase gene from lines with varied genetic backgrounds, commonly encountered in patients with pulmonary adenocarcinoma. We have characterized these lines by testing their response to multiple drugs. Thus, we have developed orthotopic preclinical mouse models of NSCLC with very high engraftment efficiency. These models allow the easy monitoring of tumor growth, particularly in response to treatment, and of tumor cells dissemination in the body. We show that concomitant treatment with osimertinib (3rd generation tyrosine kinase inhibitor targeting mutated EGFR) and bevacizumab (anti-angiogenic targeting VEGF) can have a beneficial therapeutic effect on EGFRmutated tumors. We also show that the addition of afatinib to osimertinib-treated tumors in escape leads to tumor growth inhibition. No such effect is observed with selumetinib or simvastatin. These preclinical mouse models therefore make it possible to test innovative therapeutic combinations and are also a tool of choice for studying resistance mechanisms.
ABSTRACT:The available antipsychotics for schizophrenia (SZ) only reduce positive symptoms and do not significantly modify SZ neurobiology. This has raised the question of the robustness and translational value of methods employed during drug development. Electroencephalography (EEG)- based measures like evoked and spontaneous gamma oscillations are considered robust translational biomarkers as they can be recorded in both patients and animal models to probe a key mechanism underlying all SZ symptoms: the excitation/inhibition imbalance mediated by N-methyl-D-aspartate receptor (NMDAr) hypofunction. Understanding the effects of commercialized atypical antipsychotics on such measures could therefore contribute to developing better therapies for SZ. Yet, the effects of such drugs on these EEG readouts are unknown. Here, we studied the effect of the atypical antipsychotic aripiprazole on the gamma-band auditory steady-state response (ASSR), spontaneous gamma oscillations and behavioral features in a SZ rat model induced by the NMDAr antagonist MK-801. Interestingly, we found that aripiprazole could not normalize MK-801-induced abnormalities in ASSR, spontaneous gamma oscillations or social interaction while it still improved MK-801-induced hyperactivity. Suggesting that aripiprazole is unable to normalize electrophysiological features underlying SZ symptoms, our results might explain aripiprazole’s inefficacy towards the social interaction deficit in our model but also its limited efficacy against social symptoms in patients.
ABSTRACT: Fistulizing anoperineal lesions are severe complications of Crohn’s disease (CD) that affect quality of life with a long-term risk of anal sphincter destruction, incontinence, permanent stoma, and anal cancer. Despite several surgical procedures, they relapse in about two-thirds of patients, mandating innovative treatments. Ultrasmall particles of iron oxide (USPIO) have been described to achieve in vivo rapid healing of deep wounds in the skin and liver of rats thanks to their nanobridging capability that could be adapted to fistula treatment. Our main purpose was to highlight preclinical data with USPIO for the treatment of perianal fistulizing CD. Twenty male Sprague Dawley rats with severe 2,4,6 trinitrobenzenesulfonic acid solution (TNBS)-induced proctitis were operated to generate two perianal fistulas per rat. At day 35, two inflammatory fistulas were obtained per rat and perineal magnetic resonance imaging (MRI) was performed. After a baseline MRI, a fistula tract was randomly drawn and topically treated either with saline or with USPIO for 1 min (n = 17 for each). The rats underwent a perineal MRI on postoperative days (POD) 1, 4, and 7 and were sacrificed for pathological examination. The primary outcome was the filling or closure of the fistula tract, including the external or internal openings. USPIO treatment allowed the closure and/or filling of all the treated fistulas from its application until POD 7 in comparison with the control fistulas (23%). The treatment with USPIO was safe, permanently closed the fistula along its entire length, including internal and external orifices, and paved new avenues for the treatment of perianal fistulizing Crohn’s disease.
ABSTRACT : Osimertinib is a third generation tyrosine kinase inhibitor (TKI) that targets the epidermal growth factor receptor (EGFR) in lung cancer. However, although this molecule is not subject to some of the resistance mechanisms observed in response to first generation TKIs, ultimately, patients relapse because of unknown resistance mechanisms. New relevant non-small cell lung cancer (NSCLC) mice models are therefore required to allow the analysis of these resistance mechanisms and to evaluate the efficacy of new therapeutic strategies.
Briefly, PC-9 cells, previously modified for luciferase expression, were injected into the tail vein of mice. Tumor implantation and longitudinal growth, almost exclusively localized in the lung, were evaluated by bioluminescence. Once established, the tumor was treated with osimertinib until tumor escape and development of bone metastases.
Micro-metastases were detected by bioluminescence and collected for further analysis.
We describe an orthotopic model of NSCLC protocol that led to lung primary tumor nesting and, after osimertinib treatment, by metastases dissemination, and that allow the isolation of these small osimertinib-resistant micro-metastases. This model provides new biological tools to study tumor progression from the establishment of a lung tumor to the generation of drug-resistant micro-metastases, mimicking the natural course of the disease in human NSCLC patients.
Orthotopic lung tumor model, Metastasis, Bioluminescence, EGFR TK inhibitor, Tumor escape, Osimertinib
ABSTRACT: Circulating tumor cells (CTC) have been studied in various solid tumors but clinical utility of CTC in small cell lung cancer (SCLC) remains unclear. The aim of the CTC-CPC study was to develop an EpCAM-independent CTC isolation method allowing isolation of a broader range of living CTC from SCLC and decipher their genomic and
