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Aims: Homeopathic complex Tepeex® is a compound of Actaea racemosa 4cH, Natrum muriaticum 2cH, Pulsatilla nigricans 3cH, Chamomilla 3cH and Sepia succus5cH. This study evaluated the effect of Tepeex® in pre-clinical models of depression and anxiety. Methods: the following tests were performed: elevated plus maze test (EPM); forced swimming test (FST); open field test (OFT) and Rotarod test (RRT). Results: In EPM, animals treated with Tepeex® on days 20 and 30 stayed longer in the open arms of the maze than the control group (p < 0.05, Dunnett test). In FST, treatment with Tepeex® did not increase swimming time compared to the control group in any phase of treatment. In OFT, crossing increased significantly with treatment with amfepramone, and also with 30-day treatment with Tepeex® (p < 0.05, Dunnette test). In RRT, treatment with amfepramone significantly reduced latency time. 30-day treatment with Tepeex® did not affect motor coordination when compared to the control group. Conclusion: results suggest that homeopathic complex Tepeex® has anxiolytic properties without affecting motor coordination.

Poly(ADP-ribose) polymerase (PARP) inhibitors (PARPi) are now a first-line maintenance treatment in ovarian cancer and have been approved in other cancer types, including breast, pancreatic and prostate. Despite their efficacy, and as is the case for other targeted therapies, resistance to PARPi has been reported clinically and is generating a growing patient population of unmet clinical need. Here, we discuss the mechanisms of resistance that have been described in pre-clinical models and focus on those that have been already identified in the clinic, highlighting the key challenges to fully characterise the clinical landscape of PARPi resistance and proposing ways of preventing and overcoming it.

Abstract Three-dimensional cell technologies as pre-clinical models are emerging tools for mimicking the structural and functional complexity of the nervous system. The accurate exploration of phenotypes in engineered 3D neuronal cultures, however, demands morphological, molecular and especially functional measurements. Particularly crucial is measurement of electrical activity of individual neurons with millisecond resolution. Current techniques rely on customized electrophysiological recording set-ups, characterized by limited throughput and poor integration with other readout modalities. Here we describe a novel approach, using multiwell glass microfluidic microelectrode arrays, allowing non-invasive electrical recording from engineered 3D neural tissues. We demonstrate parallelized studies with reference compounds, calcium imaging and optogenetic stimulation. Additionally, we show how microplate compatibility allows automated handling and high-content analysis of human induced pluripotent stem cell–derived neurons. This microphysiological platform opens up new avenues for high-throughput studies on the functional, morphological and molecular details of neurological diseases and their potential treatment by therapeutic compounds.

Background: The homeopathic complex Homeo-Pax® has been used as an antidepressant and anxiolytic homeopathic medicine available in Brazil. It is a complex mixture prepared with Aconitum nap. 6cH, Aurum met. 6cH, Phosphorus 6cH, Argentum nitricum 6cH, Arsenicum alb. 6cH, and Valeriana officinalis 3cH. Aims: This study had evaluated the behavior in rats after treatment with Homeo-Pax® in pre-clinical models of depression and anxiety. Mathods: Elevated Plus Maze Test (EPM), Forced Swimming Test (FST), Open Field Test (OFT) and the Rota Rod Test (RRT) behavior assays were used to confirm its activity. In the EPM, the animals treated with Homeo-pax® on the 1st day and until the 20th day of treatment remained longer in the open arms of the maze than on 30th day. This result was statistically significant compared with the control group (p < 0.05). In the FST, the treatment with Homeo-pax® (0.5 ml, p.o) increased the swimming time, compared to the control group. This effect was dependent on treatment time, resulting in a similar effect to that presented by amfepramone (10 mg/kg, p.o). In the OFT, crossing by the animals was significantly increased by the treatment with amfepramone (10mg/kg, p.o), and also with the 30-day treatment with Homeo-pax®. In the RRT, the 30-day treatment with Homeo-pax® (0.5 ml, p.o) did not affect the animals’ motor coordination, compared with the control group, which presented the same behavior. Conclusion: Based on the results obtained, it can be suggested that the homeopathic complex Homeo-pax® has anxiolytic and antidepressant properties without affecting motor coordination capacity.

Despite the success of immune checkpoint inhibitors that target cytotoxic lymphocyte antigen-4 (CTLA-4) and programmed-cell-death-1 (PD-1) in the treatment of metastatic melanoma, there is still great need to develop robust options for patients who are refractory to first line immunotherapy. As such there has been a resurgence in interest of adoptive cell transfer (ACT) particularly derived from tumor infiltrating lymphocytes. Moreover, the addition of cyclin dependent kinase 4/6 inhibitors (CDK4/6i) have been shown to greatly extend duration of response in combination with BRAF-MEK inhibitors (BRAF-MEKi) in pre-clinical models of melanoma. We therefore investigated whether combinations of BRAF-MEK-CDK4/6i and ACT were efficacious in murine models of melanoma. Triplet targeted therapy of BRAF-MEK-CDK4/6i with OT-1 ACT led to sustained and robust anti-tumor responses in BRAFi sensitive YOVAL1.1. We also show that BRAF-MEKi but not CDK4/6i enhanced MHC Class I expression in melanoma cell lines in vitro. Paradoxically CDK4/6i in low concentrations of IFN-γ reduced expression of MHC Class I and PD-L1 in YOVAL1.1. Overall, this work provides additional pre-clinical evidence to pursue combination of BRAF-MEK-CDK4/6i and to combine this combination with ACT in the clinic.

Alzheimer’s disease effects a large percentage of elderly dementia patients and is diagnosed on the basis of amyloid plaques and neurofibrillary tangles (NFTs) present in the brain. Urinary incontinence (UI) is often found in the elderly populations and multiple studies have shown that it is more common in Alzheimer’s disease patients than those with normal cognitive function. However, the link between increased UI and Alzheimer’s disease is still unclear. Amyloid plaques and NFTs present in micturition centers of the brain could cause a loss of signal to the bladder, resulting in the inability to properly void. Additionally, as Alzheimer’s disease progresses, patients become less likely to recognize the need or understand the appropriate time and place to void. There are several treatments for UI targeting the muscarinic and β3 adrenergic receptors, which are present in the bladder and the brain. While these treatments may aid in UI, they often have effects on the brain with cognitive impairment side-effects. Acetylcholine esterase inhibitors are often used in treatment of Alzheimer’s disease and directly oppose effects of anti-muscarinics used for UI, making UI management in Alzheimer’s disease patients difficult. There are currently over 200 pre-clinical models of Alzheimer’s disease, however, little research has been done on voiding disfunction in these models. There is preliminary data suggesting these models have similar voiding behavior to Alzheimer’s disease patients but much more research is needed to understand the link between UI and Alzheimer’s disease and discover better treatment options for managing both simultaneously.

Despite encouraging progress over the past decade, malaria remains a major global health challenge. Its severe form accounts for the majority of malaria-related deaths, and early diagnosis is key for a positive outcome. However, this is hindered by the non-specific symptoms caused by malaria, which often overlap with those of other viral, bacterial and parasitic infections. In addition, current tools are unable to detect the nature and degree of vital organ dysfunction associated with severe malaria, as complications develop silently until the effective treatment window is closed. It is therefore crucial to identify cheap and reliable early biomarkers of this wide-spectrum disease. microRNAs (miRNAs), a class of small non-coding RNAs, are rapidly released into the blood circulation upon physiological changes, including infection and organ damage. The present review details our current knowledge of miRNAs as biomarkers of specific organ dysfunction in patients with malaria, and both promising candidates identified by pre-clinical models and important knowledge gaps are highlighted for future evaluation in humans. miRNAs associated with infected vectors are also described, with a view to expandind this rapidly growing field of research to malaria transmission and surveillance.

Non-small cell lung cancer (NSCLC) is the most common type of lung cancer and accounts for 85% of lung cancer cases. Aberrant activation of the Signal Transducer and Activator of Transcription 3 (STAT3) is frequently observed in NSCLC and is associated with a poor prognosis. Pre-clinical studies have revealed an unequivocal role for tumor cell-intrinsic and extrinsic STAT3 signaling in NSCLC by promoting angiogenesis, cell survival, cancer cell stemness, drug resistance, and evasion of anti-tumor immunity. Several STAT3-targeting strategies have also been investigated in pre-clinical models, and include preventing upstream receptor/ligand interactions, promoting the degradation of STAT3 mRNA, and interfering with STAT3 DNA binding. In this review, we discuss the molecular and immunological mechanisms by which persistent STAT3 activation promotes NSCLC development, and the utility of STAT3 as a prognostic and predictive biomarker in NSCLC. We also provide a comprehensive update of STAT3-targeting therapies that are currently undergoing clinical evaluation, and discuss the challenges associated with these treatment modalities in human patients.

Abstract 5-fluorouracil (5-FU) is the backbone for chemotherapy in colorectal cancer (CRC), however response rates in patients are limited to 50%. Unexpectedly, the molecular mechanisms by which 5-FU ultimately induces toxicity remain debated, limiting the development of strategies to improve its efficacy. How fundamental aspects of cancer, such as driver mutations and phenotypic intra-tumor heterogeneity, relate to the 5-FU response are ill-defined. This is largely due to a shortage of mechanistic studies in pre-clinical models able to recapitulate the key-features of CRC. Here, we analyzed the 5-FU response in human organoids genetically engineered to reproduce the different stages of CRC progression. We find that 5-FU induces pyrimidine imbalance, which leads to DNA damage and cell death. Actively proliferating cancer (stem) cells are, accordingly, efficiently targeted by 5-FU. Importantly, p53 behaves as a discriminating factor for 5-FU sensitivity, whereas p53-deficiency leads to DNA damage-induced cell death, active p53 protects from these effects through inducing cell cycle arrest. Moreover, we find that targeting the Warburg effect, by rewiring glucose metabolism, enhances 5-FU toxicity by altering the nucleotide pool and without increasing toxicity in non-transformed cells. Thus, rewiring glucose metabolism in combination with replication stress-inducing chemotherapies emerges as a promising strategy for CRC treatment.

Despite intensive high-dose multimodal therapy, high-risk neuroblastoma (NB) confers a less than 50% survival rate. This study investigates the role of replication stress in sensitivity to inhibition of Ataxia telangiectasia and Rad3-related (ATR) in pre-clinical models of high-risk NB. Amplification of the oncogene MYCN always imparts high-risk disease and occurs in 25% of all NB. Here, we show that MYCN-induced replication stress directly increases sensitivity to the ATR inhibitors VE-821 and AZD6738. PARP inhibition with Olaparib also results in replication stress and ATR activation, and sensitises NB cells to ATR inhibition independently of MYCN status, with synergistic levels of cell death seen in MYCN expressing ATR- and PARP-inhibited cells. Mechanistically, we demonstrate that ATR inhibition increases the number of persistent stalled and collapsed replication forks, exacerbating replication stress. It also abrogates S and G2 cell cycle checkpoints leading to death during mitosis in cells treated with an ATR inhibitor combined with PARP inhibition. In summary, increased replication stress through high MYCN expression, PARP inhibition or chemotherapeutic agents results in sensitivity to ATR inhibition. Our findings provide a mechanistic rationale for the inclusion of ATR and PARP inhibitors as a potential treatment strategy for high-risk NB.