KCNT2-Related Disorders: Phenotypes, Functional, and Pharmacological Properties.

OBJECTIVE: Pathogenic variants in KCNT2 are rare causes of developmental epileptic encephalopathy (DEE). We herein describe the phenotypic and genetic features of patients with KCNT2-related DEE, and the in vitro functional and pharmacological properties of KCNT2 channels carrying 14 novel or previously untested variants. METHODS: Twenty-five patients harboring KCNT2 variants were investigated: 12 were identified through an international collaborative network, 13 were retrieved from the literature. Clinical data were collected and included in a standardized phenotyping sheet. Novel variants were detected using exome sequencing and classified using ACMG criteria. Functional and pharmacological studies were performed by whole-cell electrophysiology in HEK-293 and SH-SY5Y cells. RESULTS: The phenotypic spectrum encompassed: (a) intellectual disability/developmental delay (21/22 individuals with available information), ranging from mild to severe/profound; (b) epilepsy (15/25); (c) neurological impairment, with altered muscle tone (14/22); (d) dysmorphisms (13/20). Nineteen pathogenic KCNT2 variants were found (9 new, 10 reported previously): 16 missense, 1 in-frame deletion of a single amino acid, 1 nonsense, and 1 frameshift. Among tested variants, 8 showed gain-of-function (GoF), and 6 loss-of-function (LoF) features when expressed heterologously in vitro. Quinidine and fluoxetine blocked all GoF variants, whereas loxapine and riluzole activated some LoF variants while blocking others. INTERPRETATION: We expanded the phenotypic and genotypic spectrum of KCNT2-related disorders, highlighting novel genotype-phenotype associations. Pathogenic KCNT2 variants cause GoF or LoF in vitro phenotypes, and each shows a unique pharmacological profile, suggesting the need for in vitro functional and pharmacological investigation to enable targeted therapies based on the molecular phenotype. ANN NEUROL 2023;94:332-349.

Calcium cytotoxicity sensitizes prostate cancer cells to standard-of-care treatments for locally advanced tumors.

Therapy resistance is a major roadblock in oncology. Exacerbation of molecular dysfunctions typical of cancer cells have proven effective in twisting oncogenic mechanisms to lethal conditions, thus offering new therapeutic avenues for cancer treatment. Here, we demonstrate that selective agonists of Transient Receptor Potential cation channel subfamily M member 8 (TRPM8), a cation channel characteristic of the prostate epithelium frequently overexpressed in advanced stage III/IV prostate cancers (PCa), sensitize therapy refractory models of PCa to radio, chemo or hormonal treatment. Overall, our study demonstrates that pharmacological-induced Ca2+ cytotoxicity is an actionable strategy to sensitize cancer cells to standard therapies.

Sustainability of Long-term Care: Puzzling Tasks Ahead for Policy-Makers.

BACKGROUND: The sustainability of long-term care (LTC) is a prominent policy priority in many Western countries. LTC is one of the most pressing fiscal issues for the growing population of elderly people in the European Union (EU) Member States. Country recommendations regarding LTC are prominent under the EU's European Semester. METHODS: This paper examines challenges related to the financial- and organizational sustainability of LTC systems in the EU. We combined a targeted literature review and a descriptive selected country analysis of: (1) public- and private funding; (2) informal care and externalities; and (3) the possible role of technology in increasing productivity. Countries were selected via purposive sampling to establish a cohort of country cases covering the spectrum of differences in LTC systems: public spending, private funding, informal care use, informal care support, and cash benefits. RESULTS: The aging of the population, the increasing gap between availability of informal care and demand for LTC, substantial market failures of private funding for LTC, and fiscal imbalances in some countries, have led to structural reforms and enduring pressures for LTC policy-makers across the EU. Our exploration of national policies illustrates different solutions that attempt to promote fairness while stimulating efficient delivery of services. Important steps must be taken to address the sustainability of LTC. First, countries should look deeper into the possibilities of complementing public- and private funding, as well as at addressing market failures of private funding. Second, informal care externalities with spill-over into neighboring policy areas, the labor force, and formal LTC workers, should be properly addressed. Thirdly, innovations in LTC services should be stimulated to increase productivity through technology and process innovations, and to reduce costs. CONCLUSION: The analysis shows why it is difficult for EU Member State governments to meet all their goals for sustainable LTC, given the demographic- and fiscal circumstances, and the complexities of LTC systems. It also shows the usefulness to learn from policy design and implementation of LTC policy in other countries, within and outside the EU. Researchers can contribute by studying conditions, under which the strategies explored might deliver solutions for policy-makers.

Effects of natural and synthetic isothiocyanate-based H2S-releasers against chemotherapy-induced neuropathic pain: Role of Kv7 potassium channels.

Hydrogen sulfide (H2S) is a crucial signaling molecule involved in several physiological and pathological processes. Nonetheless, the role of this gasotransmitter in the pathogenesis and treatment of neuropathic pain is controversial. The aim of the present study was to investigate the pain relieving profile of a series of slow releasing H2S donors (the natural allyl-isothiocyanate and the synthetics phenyl- and carboxyphenyl-isothiocyanate) in animal models of neuropathic pain induced by paclitaxel or oxaliplatin, anticancer drugs characterized by a dose-limiting neurotoxicity. The potential contribution of Kv7 potassium channels modulation was also studied. Mice were treated with paclitaxel (2.0 mg kg-1) i.p. on days 1, 3, 5 and 7; oxaliplatin (2.4 mg kg-1) was administered i.p. on days 1-2, 5-9, 12-14. Behavioral tests were performed on day 15. In both models, single subcutaneous administrations of H2S donors (1.33, 4.43, 13.31 µmol kg-1) reduced the hypersensitivity to cold non-noxious stimuli (allodynia-related measurement). The prototypical H2S donor NaHS was also effective. Activity was maintained after i.c.v. administrations. On the contrary, the S-lacking molecule allyl-isocyanate did not increase pain threshold; the H2S-binding molecule hemoglobin abolished the pain-relieving effects of isothiocyanates and NaHS. The anti-neuropathic properties of H2S donors were reverted by the Kv7 potassium channel blocker XE991. Currents carried by Kv7.2 homomers and Kv7.2/Kv7.3 heteromers expressed in CHO cells were potentiated by H2S donors. Sistemically- or centrally-administered isothiocyanates reduced chemotherapy-induced neuropathic pain by releasing H2S. Activation of Kv7 channels largely mediate the anti-neuropathic effect.

Characterization of two de novoKCNT1 mutations in children with malignant migrating partial seizures in infancy.

The KCNT1 gene encodes for subunits contributing to the Na(+)-activated K(+) current (KNa), expressed in many cell types. Mutations in KCNT1 have been found in patients affected with a wide spectrum of early-onset epilepsies, including Malignant Migrating Partial Seizures in Infancy (MMPSI), a severe early-onset epileptic encephalopathy characterized by pharmacoresistant focal seizures migrating from one brain region or hemisphere to another and neurodevelopment arrest or regression, resulting in profound disability. In the present study we report identification by whole exome sequencing (WES) of two de novo, heterozygous KCNT1 mutations (G288S and, not previously reported, M516V) in two unrelated MMPSI probands. Functional studies in a heterologous expression system revealed that channels formed by mutant KCNT1 subunits carried larger currents when compared to wild-type KCNT1 channels, both as homo- and heteromers with these last. Both mutations induced a marked leftward shift in homomeric channel activation gating. Interestingly, the KCNT1 blockers quinidine (3-1000µM) and bepridil (0.03-10µM) inhibited both wild-type and mutant KCNT1 currents in a concentration-dependent manner, with mutant channels showing higher sensitivity to blockade. This latter result suggests two genotype-tailored pharmacological strategies to specifically counteract the dysfunction of KCNT1 activating mutations in MMPSI patients.

Effects of regulated competition on key outcomes of care: cataract surgeries in the Netherlands.

Similar to several other countries, the Netherlands implemented market-oriented health care reforms in recent years. Previous studies raised questions on the effects of these reforms on key outcomes such as quality, costs, and prices. The empirical evidence is up to now mixed. This study looked at the variation in prices, volume, and quality of cataract surgeries since the introduction of price competition in 2006. We found no price convergence over time and constant price differences between hospitals. Quality indicators generally showed positive results in cataract care, though the quality and scope of the indicators was suboptimal at this stage. Furthermore, we found limited between-hospital variation in quality and there was no clear-cut relation between prices and quality. Volume of cataract care strongly increased in the period studied. These findings indicate that health insurers may not have been able to drive prices down, make trade-offs between price and quality, and selectively contract health care without usable quality information. Positive results coming out from the 2006 reform should not be taken for granted. Looking forward, future research on similar topics and with newer data should clarify the extent to which these findings can be generalized.