Neuroendocrine differentiation of prostate epithelial cells is usually associated with an increased aggressivity and invasiveness of prostate tumors and a poor prognosis. However, the molecular mechanisms involved in this process remain poorly understood. We have investigated the possible expression of voltage-gated calcium channels in human prostate cancer epithelial LNCaP cells and their modulation during neuroendocrine differentiation. A small proportion of undifferentiated LNCaP cells displayed a voltage-dependent calcium current. This proportion and the calcium current density were significantly increased during neuroendocrine differentiation induced by long-term treatments with cyclic AMP permeant analogs or with a steroid-reduced culture medium. Biophysical and pharmacological properties of this calcium current suggest that it is carried by low-voltage activated T-type calcium channels. Reverse transcriptase-PCR experiments demonstrated that only a single type of LVA calcium channel mRNA, an α_1H calcium channel mRNA, is expressed in LNCaP cells. Quantitative real-time reverse transcriptase-PCR revealed that α_1H mRNA was overexpressed during neuroendocrine differentiation. Finally, we show that this calcium channel promotes basal calcium entry at resting membrane potential and may facilitate neurite lengthening. This voltage-dependent calcium channel could be involved in the stimulation of mitogenic factor secretion and could therefore be a target for future therapeutic strategies.

Background— Cardiac hypertrophy underlies arrhythmias and sudden death, for which mineralocorticoid receptor (MR) activity has recently been implicated. We sought to establish the sequence of ionic events that link the initiating insult and MR to hypertrophy development. Methods and Results— Using whole-cell, patch-clamp and quantitative reverse transcription–polymerase chain reaction techniques on right ventricular myocytes of a myocardial infarction (MI) rat model, we examined the cellular response over time. One week after MI, no sign of cellular hypertrophy was found, but action potential duration (APD) was lengthened. Both an increase in Ca ²⁺ current ( I _Ca ) and a decrease in K ⁺ transient outward current ( I _to ) underlay this effect. Consistently, the relative expression of mRNA coding for the Ca ²⁺ channel α1C subunit (Ca _v 1.2) increased, and that of the K ⁺ channel K _v 4.2 subunit decreased. Three weeks after MI, AP prolongation endured, whereas cellular hypertrophy developed. I _Ca density, Ca _v 1.2, and K _v 4.2 mRNA levels regained control levels, but I _to density remained reduced. Long-term treatment with RU28318, an MR antagonist, prevented this electrical remodeling. In a different etiologic model of abdominal aortic constriction, we confirmed that APD prolongation and modifications of ionic currents precede cellular hypertrophy. Conclusions— Electrical remodeling, which is triggered at least in part by MR activation, is an initial, early cellular response to hypertrophic insults.

Sex and gender dimorphisms are found in a large variety of diseases, including sepsis and septic shock which are more prevalent in men than in women. Animal models show that the host response to pathogens differs in females and males. This difference is partially explained by sex polarization of the intracellular pathways responding to pathogen–cell receptor interactions. Sex hormones seem to be responsible for this polarization, although other factors, such as chromosomal effects, have yet to be investigated. In brief, females are less susceptible to sepsis and seem to recover more effectively than males. Clinical observations produce more nuanced findings, but men consistently have a higher incidence of sepsis, and some reports also claim higher mortality rates. However, variables other than hormonal differences complicate the interaction between sex and sepsis, including comorbidities as well as social and cultural differences between men and women. Conflicting data have also been reported regarding sepsis-attributable mortality rates among pregnant women, compared with non-pregnant females. We believe that unraveling sex differences in the host response to sepsis and its treatment could be the first step in personalized, phenotype-based management of patients with sepsis and septic shock.

Background Myocarditis is a rare but life-threatening adverse event of cancer treatments with immune checkpoint inhibitors (ICIs). Recent guidelines recommend the use of high doses of corticosteroids as a first-line treatment, followed by intensified immunosuppressive therapy (IIST) in the case of unfavorable evolution. However, this strategy is empirical, and no studies have specifically addressed this issue. Therefore, we aimed to investigate and compare the clinical course, management and outcome of ICI-induced myocarditis patients requiring or not requiring IIST. Methods This case–control study included all patients consecutively admitted to The Mediterranean University Center of Cardio-Oncology (Aix-Marseille University, France) for the diagnosis of ICI-induced myocarditis according to Bonaca’s criteria and treated with or without IIST. In addition, we searched PubMed and included patients from previously published case reports treated with IIST in the analysis. The clinical, biological, imaging, treatment, all-cause death and cardiovascular death data of patients who required IIST were compared with those of patients who did not. Results A total of 60 patients (69±12 years) were included (36 were treated with IIST and 24 were not). Patients requiring IIST were more likely to have received a combination of ICIs (39% vs 8%, p=0.01), and developed the first symptoms/signs of myocarditis earlier after the onset of ICI therapy (median, 18 days vs 60 days, p=0.002). They had a significantly higher prevalence of sustained ventricular arrhythmia, complete atrioventricular block, cardiogenic shock and troponin elevation. Moreover, they were more likely to have other immune-related adverse events simultaneously (p<0.0001), especially myositis (p=0.0002) and myasthenia gravis (p=0.009). Patients who required IIST were more likely to die from any cause (50% vs 21%, p=0.02). Among them, patients who received infliximab were more likely to die from cardiovascular causes (OR, 12.0; 95% CI 2.1 to 67.1; p=0.005). Conclusion The need for IIST was more common in patients who developed myocarditis very early after the start of ICI therapy, as well as when hemodynamic/electrical instability or neuromuscular adverse events occurred. Treatment with infliximab might be associated with an increased risk of cardiovascular death.