A highly predictive 3D-QSAR model for binding to the voltage-gated sodium channel: design of potent new ligands

Ruthenium(II)-Catalyzed Regioselective [3 + 2] Spiroannulation of 2H-Imidazoles with 2-Alkynoates

The C═N double bond of 2H-imidazole has been employed as a C-electrophile for the ruthenium(II)-catalyzed [3 + 2] spiroannulation reaction of 4-phenyl-2H-imidazoles and 2-alkynoates to synthesize spiroimidazole-4,1'-indenes. This strategy features high regioselectivity, broad functional group tolerance, and use of ruthenium as a catalyst, providing a new method to synthesize spirocycles with potential applications in pharmaceuticals.

The Functional Role of Voltage-Gated Sodium Channel Nav1.5 in Metastatic Breast Cancer

Voltage-gated sodium channels (VGSCs), which are abnormally expressed in various types of cancers such as breast cancer, prostate cancer, lung cancer, and cervical cancer, are involved in the metastatic process of invasion and migration. Nav1.5 is a pore-forming α subunit of VGSC encoded by SCN5A. Various studies have demonstrated that Nav1.5, often as its neonatal splice form, is highly expressed in metastatic breast cancer cells. Abnormal activation and expression of Nav1.5 trigger a variety of cellular mechanisms, including changing H+ efflux, promoting epithelial-to-mesenchymal transition (EMT) and the expression of cysteine cathepsin, to potentiate the metastasis and invasiveness of breast cancer cells in vitro and in vivo. Here, we systematically review the latest available data on the pro-metastatic effect of Nav1.5 and its underlying mechanisms in breast cancer. We summarize the factors affecting Nav1.5 expression in breast cancer cells, and discuss the potential of Nav1.5 blockers serving as candidates for breast cancer treatment.

Quantitative structure-activity relationship models for compounds with anticonvulsant activity

Introduction: Third-generation antiepileptic drugs have seemingly failed to improve the global figures of seizure control and can still be regarded as symptomatic treatments. Quantitative structure-activity relationships (QSAR) can be used to guide hit-to-lead and lead optimization projects and applied to the large-scale virtual screening of chemical libraries. Areas covered: In this review, the authors cover reports on QSAR models related to antiepileptic drugs and drug targets in epilepsy, analyzing whether they refer to classic or non-classic QSAR and if they apply QSAR as a descriptive or predictive approach, among other considerations. The article finally focuses on a more detailed discussion of those predictive studies which include some sort of experimental validation, i.e. papers in which the reported models have been used to identify novel active compounds which have been tested in vitro and/or in vivo. Expert opinion: There are significant opportunities to apply the QSAR methodology to assist the discovery of more efficacious antiepileptic drugs. Considering the intrinsic complexity of the disorder, such applications should focus on state-of-the-art approximations (e.g. systemic, multi-target and multi-scale QSAR as well as ensemble and deep learning) and modeling the effects on novel drug targets and modern screening tools.

Discovery and evaluation of nNav1.5 sodium channel blockers with potent cell invasion inhibitory activity in breast cancer cells

Voltage-gated sodium channels (VGSC) are a well-established drug target for anti-epileptic, anti-arrhythmic and pain medications due to their presence and the important roles that they play in excitable cells. Recently, their presence has been recognized in non-excitable cells such as cancer cells and their overexpression has been shown to be associated with metastatic behavior in a variety of human cancers. The neonatal isoform of the VGSC subtype, Na_v1.5 (nNa_v1.5) is overexpressed in the highly aggressive human breast cancer cell line, MDA-MB-231. The activity of nNa_v1.5 is known to promote the breast cancer cell invasion in vitro and metastasis in vivo, and its expression in primary mammary tumors has been associated with metastasis and patient death. Metastasis development is responsible for the high mortality of breast cancer and currently there is no treatment available to specifically prevent or inhibit breast cancer metastasis. In the present study, a 3D-QSAR model is used to assist the development of low micromolar small molecule VGSC blockers. Using this model, we have designed, synthesized and evaluated five small molecule compounds as blockers of nNa_v1.5-dependent inward currents in whole-cell patch-clamp experiments in MDA-MB-231 cells. The most active compound identified from these studies blocked sodium currents by 34.9 ± 6.6% at 1 μM. This compound also inhibited the invasion of MDA-MB-231 cells by 30.3 ± 4.5% at 1 μM concentration without affecting the cell viability. The potent small molecule compounds presented here have the potential to be developed as drugs for breast cancer metastasis treatment.