Uptake of biodegradable poly(γ-glutamic acid) nanoparticles and antigen presentation by dendritic cells in vivo

AbstractPoly(γ-glutamic acid) (γ-PGA) nanoparticles (NPs) carrying antigens have been shown to induce potent antigen-specific immune responses. However, in vivo delivery of γ-PGA NPs to dendritic cells (DCs), a key regulator of immune responses, still remains unclear. In this study, γ-PGA NPs were examined for their uptake by DCs and subsequent migration from the skin to the regional lymph nodes (LNs) in mice. After subcutaneous injection of fluorescein 5-isothiocyanate (FITC)-labeled NPs or FITC-ovalbumin (OVA)-carrying NPs (FITC-OVA-NPs), DCs migrated from the skin to the LNs and maturated, resulting in the upregulation of the costimulatory molecules CD80 and CD86 and the chemokine receptor CCR7. However, the migrated DCs were not detected in the spleen. FITC-OVA-NPs were found to be taken up by skin-derived CD103+ DCs, and the processed antigen peptides were cross-presented by the major histocompatibility complex (MHC) class I molecule of DCs. Furthermore, significant activation of antigen-specific CD8+ T cells was observed in mice immunized with OVA-carrying NPs (OVA-NPs) but not with OVA alone or OVA with an aluminum adjuvant. The antigen-specific CD8+ T cells were induced within 7 days after immunization with OVA-NPs. Thus, γ-PGA NPs carrying various antigens may have great potential as an antigen-delivery system and vaccine adjuvant in vivo

CSC with and without steroids

We investigated the rates of the use of steroids in Japanese central serous chorioretinopathy (CSC) cases and differences in the characteristics of CSC with and without steroids. A total of 538 eyes of 477 patients diagnosed with CSC, with 3 months or more of follow-up between April 2013 and June 2017 at 8 institutions. Patients with CSC with more than 3 months of follow-up were identified by OCT and fluorescein angiography at 8 institutions. Data collected included patient demographics, history of corticosteroid medication and smoking, spherical errors, findings of angiography, subfoveal choroidal thickness, and changes through the follow-up period. Differences in these findings were analyzed in cases with and without corticosteroid treatment. Among the 477 patients (344 men,133 women), 74 (15.5%) (39 men, 35 women) underwent current or prior steroid treatment. Cases with steroids were higher age (p = 0.0403) and showed no male prevalence, more bilateral involvement (p < 0.0001), and the affected eyes had multiple pigment epithelial detachment (p <0.0001), more fluorescein leakage sites (p < 0.0001), greater choroidal thickness (p = 0.0287) and a higher recurrence rate (p = 0.0412). Steroids can cause severer CSC through an effect on choroidal vessels and an impairment of retinal pigment epithelium

光異性化反応によるスリンダクの生態毒性の増強

　近年、世界各地の河川や湖沼等の水環境中から医薬品を検出した事例が数多く報告されている。それに伴い、医薬品の生態系への影響や環境中での挙動が注目されているが、多くの医薬品において、知見に乏しいのが現状である。本研究では、解熱鎮痛剤であるスリンダクについて、水生生物に対する影響が紫外線照射により変化するかについて、ISO11348-1に準拠した生態毒性試験により検討した。すなわち、スリンダク、紫外線（主波長302 nm）を照射したスリンダクおよびスリンダク光分解物の水溶液を海洋発光細菌V. fischeriに暴露し、発光の減少量から毒性の大小を評価した。その結果、紫外線を照射することでスリンダクの毒性は有意に増強し、それには生成した光分解物であるスリンダクのtrans体が大きく寄与することが明らかとなった。今回の結果より、医薬品の環境リスクアセスメントを行う上で、親化合物だけでなくその環境下での分解物についても評価が必要であることが示唆された

Case report: Rare heterozygous variant in the NR5A1 gene causing 46,XY complete gonadal dysgenesis with a non-communicating rudimentary uterus

The nuclear receptor subfamily 5 group A member 1 (NR5A1) gene encodes NR5A1, also known as steroidogenic factor 1, a crucial transcriptional factor regulating adrenal and gonadal development and function. Although pathogenic variants in NR5A1 are known to cause a spectrum of disorders of sex development (DSD), individuals with 46,XY DSD with fully female internal and external genitalia are relatively rare. Herein, we present the case of a patient with 46,XY complete gonadal dysgenesis (CGD) who had a non-communicating rudimentary uterus due to a c.132_134del (p.Asn44del) heterozygous in-frame-deletion in NR5A1 that was diagnosed while treating a pelvic mass in which gynecological malignancy could not be disregarded. Unlike two previous cases with the p.Asn44del variant, this case presented with CGD, a severe DSD phenotype, and we found that the oligogenic inheritance of DSD-causative genes such as SRY, DHX37, SLC26A8, and CFTR may have affected the severity of the clinical phenotype

CDK4/6 signaling attenuates the effect of epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors in EGFR-mutant non-small cell lung cancer

Background: Epidermal growth factor receptor (EGFR) mutations, such as exon 19 deletion and exon 21 L858R, are driver oncogenes of non-small cell lung cancer (NSCLC), with EGFR tyrosine kinase inhibitors (TKIs) being effective against EGFR-mutant NSCLC. However, the efficacy of EGFR-TKIs is transient and eventually leads to acquired resistance. Herein, we focused on the significance of cell cycle factors as a mechanism to attenuate the effect of EGFR-TKIs in EGFR-mutant NSCLC before the emergence of acquired resistance. Methods: Using several EGFR-mutant cell lines, we investigated the significance of cell cycle factors to attenuate the effect of EGFR-TKIs in EGFR-mutant NSCLC. Results: In several EGFR-mutant cell lines, certain cancer cells continued to proliferate without EGFR signaling, and the cell cycle regulator retinoblastoma protein (RB) was not completely dephosphorylated. Further inhibition of phosphorylated RB with cyclin-dependent kinase (CDK) 4/6 inhibitors, combined with the EGFR-TKI osimertinib, enhanced G0/G1 cell cycle accumulation and growth inhibition of the EGFR-mutant NSCLC in both in vitro and in vivo models. Furthermore, residual RB phosphorylation without EGFR signaling was maintained by extracellular signal-regulated kinase (ERK) signaling, and the ERK inhibition pathway showed further RB dephosphorylation. Conclusions: Our study demonstrated that the CDK4/6-RB signal axis, maintained by the MAPK pathway, attenuates the efficacy of EGFR-TKIs in EGFR-mutant NSCLC, and targeting CDK4/6 enhances this efficacy. Thus, combining CDK4/6 inhibitors and EGFR-TKI could be a novel treatment strategy for TKI-naïve EGFR-mutant NSCLC

Efficacy of gilteritinib in comparison with alectinib for the treatment of ALK-rearranged non-small cell lung cancer

Gilteritinib is a multitarget tyrosine kinase inhibitor (TKI), approved for the treatment of FLT3-mutant acute myeloid leukemia, with a broad range of activity against several tyrosine kinases including anaplastic lymphoma kinase (ALK). This study investigated the efficacy of gilteritinib against ALK-rearranged non-small cell lung cancers (NSCLC). To this end, we assessed the effects of gilteritinib on cell proliferation, apoptosis, and acquired resistance responses in several ALK-rearranged NSCLC cell lines and mouse xenograft tumor models and compared its efficacy to alectinib, a standard ALK inhibitor. Gilteritinib was significantly more potent than alectinib, as it inhibited cell proliferation at a lower dose, with complete attenuation of growth observed in several ALK-rearranged NSCLC cell lines and no development of drug tolerance. Immunoblotting showed that gilteritinib strongly suppressed phosphorylated ALK and its downstream effectors, as well as mesenchymal-epithelial transition factor (MET) signaling. By comparison, MET signaling was enhanced in alectinib-treated cells. Furthermore, gilteritinib was found to more effectively abolish growth of ALK-rearranged NSCLC xenograft tumors, many of which completely receded. Interleukin-15 (IL-15) mRNA levels were elevated in gilteritinib-treated cells, together with a concomitant increase in the infiltration of tumors by natural killer (NK) cells, as assessed by immunohistochemistry. This suggests that IL-15 production along with NK cell infiltration may constitute components of the gilteritinib-mediated antitumor responses in ALK-rearranged NSCLCs. In conclusion, gilteritinib demonstrated significantly improved antitumor efficacy compared with alectinib against ALK-rearranged NSCLC cells, which can warrant its candidacy for use in anticancer regimens, after further examination in clinical trial settings