Solo regulates the localization and activity of PDZ-RhoGEF for actin cytoskeletal remodeling in response to substrate stiffness.

Recent findings indicate that Solo, a RhoGEF, is involved in cellular mechanical stress responses. However, the mechanism of actin cytoskeletal remodeling via Solo remains unclear. Therefore, this study aimed to identify Solo-interacting proteins using the BioID, a proximal-dependent labeling method, and elucidate the molecular mechanisms of function of Solo. We identified PDZ-RhoGEF (PRG) as a Solo-interacting protein. PRG colocalized with Solo in the basal area of cells, depending on Solo localization, and enhanced actin polymerization at the Solo accumulation sites. Additionally, Solo and PRG interaction was necessary for actin cytoskeletal remodeling. Furthermore, the purified Solo itself had little or negligible GEF activity, even its GEF-inactive mutant directly activated the GEF activity of PRG through interaction. Moreover, overexpression of the Solo and PRG binding domains, respectively, had a dominant-negative effect on actin polymerization and actin stress fiber formation in response to substrate stiffness. Therefore, Solo restricts the localization of PRG and regulates actin cytoskeletal remodeling in synergy with PRG in response to the surrounding mechanical environment.

Calcium influx promotes PLEKHG4B localization to cell-cell junctions and regulates the integrity of junctional actin filaments.

PLEKHG4B is a Cdc42-targeting guanine-nucleotide exchange factor implicated in forming epithelial cell-cell junctions. Here we explored the mechanism regulating PLEKHG4B localization. PLEKHG4B localized to the basal membrane in normal Ca2+ medium but accumulated at cell-cell junctions upon ionomycin treatment. Ionomycin-induced junctional localization of PLEKHG4B was suppressed upon disrupting its annexin-A2 (ANXA2)-binding ability. Thus, Ca2+ influx and ANXA2 binding are crucial for PLEKHG4B localization to cell-cell junctions. Treatments with low Ca2+ or BAPTA-AM (an intracellular Ca2+ chelator) suppressed PLEKHG4B localization to the basal membrane. Mutations of the phosphoinositide-binding motif in the pleckstrin homology (PH) domain of PLEKHG4B or masking of membrane phosphatidylinositol-4,5-biphosphate [PI(4,5)P2] suppressed PLEKHG4B localization to the basal membrane, indicating that basal membrane localization of PLEKHG4B requires suitable intracellular Ca2+ levels and PI(4,5)P2 binding of the PH domain. Activation of mechanosensitive ion channels (MSCs) promoted PLEKHG4B localization to cell-cell junctions, and their inhibition suppressed it. Moreover, similar to the PLEKHG4B knockdown phenotypes, inhibition of MSCs or treatment with BAPTA-AM disturbed the integrity of actin filaments at cell-cell junctions. Taken together, our results suggest that Ca2+ influx plays crucial roles in PLEKHG4B localization to cell-cell junctions and the integrity of junctional actin organization, with MSCs contributing to this process.

Primary lung cancer treatable with radical resection after complete remission with pembrolizumab therapy following gemcitabine and carboplatin chemotherapy for multiple metastases of bladder cancer.

Introduction: We report a patient with the complete remission of multiple metastases and primary bladder lesions of bladder cancer who developed primary lung cancer requiring radical resection. Case presentation: A 68-year-old man diagnosed with invasive bladder cancer, right hydroureteronephrosis, and multiple metastases were administered six courses of gemcitabine and carboplatin chemotherapy and thereafter has been receiving pembrolizumab therapy. Bladder cancer and multiple metastases decreased in size, whereas a ground-glass opacity lesion in the lung gradually increased in size. Fluorodeoxyglucose-positron emission tomography revealed the accumulation of fluorodeoxyglucose in the ground-glass opacity lesion only. The patient was diagnosed with primary lung cancer and underwent a thoracoscopic lobectomy. Histopathological findings showed ALK-negative, EGFR L858R mutation-positive invasive adenocarcinoma with a programmed death-ligand 1 tumor proportion score of less than 1%. Conclusion: This is the first case report of patients with the complete remission of multiple metastases of bladder cancer who developed primary lung cancer requiring radical resection.

Serum cytokine changes induced by direct hemoperfusion with polymyxin B-immobilized fiber in patients with acute respiratory failure.

BACKGROUND: Polymyxin B-immobilized Fiber therapy (PMX-DHP) may improve the prognosis of patients with rapidly progressive interstitial lung diseases (ILDs). However, the mechanisms by which PMX-DHP ameliorates oxygenation are unclear. The present study aimed to clarify the changes in serum cytokine concentrations during PMX-DHP with steroid pulse therapy. METHODS: Patients with acute respiratory failure (ARF) and rapidly progressive ILDs, acute exacerbation of idiopathic pulmonary fibrosis (IPF), or acute respiratory distress syndrome (ARDS), and treated with PMX-DHP were assessed, including patients with IPF. The serum concentrations of 38 cytokines were compared between the ARF and IPF groups before treatment. In the ARF group, cytokine levels were compared before, immediately after PMX-DHP, and the day after termination of steroid pulse therapy. RESULTS: Fourteen ARF and eight IPF patients were enrolled. A comparison of the cytokine levels before treatment initiation revealed that EGF, GRO, IL-10, MDC, IL-12p70, IL-15, sCD40L, IL-7, IP-10, MCP-1, and MIP-1ß were significantly different between the two groups. In the ARF group treated with PMX-DHP, the concentrations of MDC, IP-10, and TNF-α continuously decreased during treatment (P < 0.01). Further, the cytokine levels of GRO, IL-10, IL-1Ra, IL-5, IL-6, and MCP-1 decreased after the entire treatment period, with no change observed during the steroid-only period (P < 0.01, except GRO and MCP-1). Although PMX-DHP significantly reduced eotaxin and GM-CSF serum levels (P < 0.01 and P < 0.05), these levels did not change after treatment. CONCLUSIONS: PMX-DHP combined with steroid pulse therapy might reduce GRO, IL-10, IL-1Ra, IL-5, IL-6, and MCP-1 levels in ARF, contributing to better oxygenation in the disorder.

PLEKHG4B enables actin cytoskeletal remodeling during epithelial cell-cell junction formation.

Cell-cell junction formation requires actin cytoskeletal remodeling. Here, we show that PLEKHG4B, a Rho-guanine nucleotide exchange factor (Rho-GEF), plays a crucial role in epithelial cell-cell junction formation. Knockdown of PLEKHG4B decreased Cdc42 activity and tended to increase RhoA activity in A549 cells. A549 monolayer cells showed 'closed junctions' with closely packed actin bundles along the cell-cell contacts, but PLEKHG4B knockdown suppressed closed junction formation, and PLEKHG4B-knockdown cells exhibited 'open junctions' with split actin bundles located away from the cell-cell boundary. In Ca2+-switch assays, PLEKHG4B knockdown delayed the conversion of open junctions to closed junctions and ß-catenin accumulation at cell-cell junctions. Furthermore, PLEKHG4B knockdown abrogated the reduction in myosin activity normally seen in the later stage of junction formation. The aberrant myosin activation and impairments in closed junction formation in PLEKHG4B-knockdown cells were reverted by ROCK inhibition or LARG/PDZ-RhoGEF knockdown. These results suggest that PLEKHG4B enables actin remodeling during epithelial cell-cell junction maturation, probably by reducing myosin activity in the later stage of junction formation, through suppressing LARG/PDZ-RhoGEF and RhoA-ROCK pathway activities. We also showed that annexin A2 participates in PLEKHG4B localization to cell-cell junctions.This article has an associated First Person interview with the first author of the paper.

Ultra-high-purity iron is a novel and very compatible biomaterial.

Metals and alloys are used widely in bone prosthetic materials, stents and dental tissue reconstructions. The most common materials are stainless steels and cobalt-chromium-nickel and titanium alloys. These alloys can be easily deformed but are hard to break. However, their affinity for cells and tissues is very low. In addition, they can sometimes provoke unexpected metal allergies. Iron is an abundant trace element essential for humans. However, excess amounts in particular of Fe2+ ions are toxic. We previously succeeded in obtaining 99.9996% ultra-high-purity iron (ABIKO iron). The chemical properties of ABIKO iron are completely different from that of conventional pure iron. For example, the reaction rate in hydrochloric acid is very slow and there is barely any corrosion. Here, we found that, in the absence of any type of coating, mammalian cells could easily attach to, and normally proliferate and differentiate on, ABIKO iron. On the other hand, cell densities and proliferation rate of the surfaces of plates made from Co-Cr-Mo or Ti-6Al-4V were significantly reduced. In addition, several stress and iron response genes, HSP70, SOD1, ATM and IRP2 did not change in the cells on ABIKO iron, while these genes were induced with exogenous application of FeSO4. Cells also secreted and fastened some organics on ABIKO iron. In vitro collagen binding assay showed that ABIKO iron binds higher amount of collagens. These findings highlight ABIKO iron as a novel biocompatible prosthetic material.

Comparison of cytokine profiles between anti-ARS antibody-positive interstitial lung diseases and those with anti-MDA-5 antibodies.

INTRODUCTION/OBJECTIVES: Interstitial lung disease (ILD) is a significant cause of mortality among patients with dermatomyositis (DM) or polymyositis (PM). There are two subtypes of PM and DM often complicated with ILD: those with anti-aminoacyl-tRNA synthetase (anti-ARS) antibodies and those with anti-MDA-5-associated amyopathic DM (ADM). Our aim is to clarify the inflammatory and immunological differences between the disorders. METHODS: We retrospectively collected consecutive patients with anti-ARS-ILD and those with anti-MDA-5 antibody-positive ADM-ILD. The serum concentration of 38 cytokines was measured using a cytokine panel. The relative risks for anti-MDA-5 antibody-positive ADM-ILD were examined with univariate and multivariate logistic regression models. Spearman's rank correlation coefficient was calculated between cytokine levels and clinical parameters in the disease. Levels of cytokines were compared between anti-ARS-ILD and anti-MDA-5-positive ADM-ILD patients (alive or dead) using Dunnett's test. RESULTS: Twenty-three patients with anti-ARS-ILD and the same number of patients with anti-MDA-5-positive ADM-ILD were enrolled. The anti-MDA-5 group had poor survival (p = 0.025). Univariate logistic regression models showed that eotaxin, IL-10, IP-10, and MCP-1 were associated with the diagnosis of anti-MDA-5-positive ADM-ILD. Multivariate logistic regression models revealed that IP-10 was the most significantly associated (p = 0.001). Relationship analyses showed that IL-10 had significant positive correlations with CK (r = 0.5267, p = 0.009) and ferritin (r = 0.4528, p = 0.045). A comparison of the cytokine levels found that IP-10 was elevated in both patients who were alive and patients who had died with ADM-ILD compared with the levels in those with ARS-ILD (p = 0.003 and p = 0.001, respectively). CONCLUSIONS: Anti-MDA-5-positive ADM-ILD had poorer survival than anti-ARS-ILD. IP-10 seems to be most deeply involved in the pathophysiology of anti-MDA-5-associated ADM-ILD.Key Points• To clarify differences in the inflammatory and immunological features of anti-MDA-5-positive ADM-ILD and anti-ARS-ILD, we performed an observational study to measure serum cytokine concentrations before treatment using a multiplex immunoassay system.• Multivariate logistic regression models revealed that IP-10 was associated with the most significant relative risk for ADM-ILD with anti-MDA-5 antibodies.• Levels of IP-10 were elevated considerably in anti-MDA-5-positive survivors and nonsurvivors compared with the levels in anti-ARS patients.• These results suggest that IP-10 is the most deeply involved in the pathophysiology of anti-MDA-5-positive ADM-ILD.

The Rho-guanine nucleotide exchange factor Solo decelerates collective cell migration by modulating the Rho-ROCK pathway and keratin networks.

Collective cell migration plays crucial roles in tissue remodeling, wound healing, and cancer cell invasion. However, its underlying mechanism remains unknown. Previously, we showed that the RhoA-targeting guanine nucleotide exchange factor Solo (ARHGEF40) is required for tensile force-induced RhoA activation and proper organization of keratin-8/keratin-18 (K8/K18) networks. Here, we demonstrate that Solo knockdown significantly increases the rate at which Madin-Darby canine kidney cells collectively migrate on collagen gels. However, it has no apparent effect on the migratory speed of solitary cultured cells. Therefore, Solo decelerates collective cell migration. Moreover, Solo localized to the anteroposterior regions of cell-cell contact sites in collectively migrating cells and was required for the local accumulation of K8/K18 filaments in the forward areas of the cells. Partial Rho-associated protein kinase (ROCK) inhibition or K18 or plakoglobin knockdown also increased collective cell migration velocity. These results suggest that Solo acts as a brake for collective cell migration by generating pullback force at cell-cell contact sites via the RhoA-ROCK pathway. It may also promote the formation of desmosomal cell-cell junctions related to K8/K18 filaments and plakoglobin.

Human-specific mutations in VMAT1 confer functional changes and multi-directional evolution in the regulation of monoamine circuits.

BACKGROUND: Neurochemicals like serotonin and dopamine play crucial roles in human cognitive and emotional functions. Vesicular monoamine transporter 1 (VMAT1) transports monoamine neurotransmitters, and its variant (136Thr) is associated with various psychopathological symptoms and reduced monoamine uptake relative to 136Ile. We previously showed that two human-specific amino acid substitutions (Glu130Gly and Asn136Thr/Ile) of VMAT1 were subject to positive natural selection. However, the potential functional alterations caused by these substitutions (Glu130Gly and Asn136Thr) remain unclear. To assess functional changes in VMAT1 from an evolutionary perspective, we reconstructed ancestral residues and examined the role of these substitutions in monoamine uptake in vitro using fluorescent false neurotransmitters (FFN), which are newly developed substances used to quantitatively assay VMATs. RESULTS: Immunoblotting confirmed that all the transfected YFP-VMAT1 variants are properly expressed in HEK293T cells at comparable levels, and no significant difference was seen in the density and the size of vesicles among them. Our fluorescent assays revealed a significant difference in FFN206 uptake among VMAT1 variants: 130Glu/136Asn, 130Glu/136Thr, and 130Gly/136Ile showed significantly higher levels of FFN206 uptake than 130Gly/136Asn and 130Gly/136Thr, indicating that both 130Glu and 136Ile led to increased neurotransmitter uptake, for which 136Thr and 136Asn were comparable by contrast. CONCLUSIONS: These findings suggest that monoamine uptake by VMAT1 initially declined (from 130Glu/136Asn to 130Gly/136Thr) in human evolution, possibly resulting in higher susceptibility to the external environment of our ancestors.

Keratin-binding ability of the N-terminal Solo domain of Solo is critical for its function in cellular mechanotransduction.

Solo (ARHGEF40) is a RhoA-targeting guanine nucleotide exchange factor that regulates tensional force-induced cytoskeletal reorganization. Solo binds to keratin 8/keratin 18 (K8/K18) filaments through multiple sites, but the roles of these interactions in the localization and mechanotransduction-regulating function of Solo remain unclear. Here, we constructed two Solo mutants (L14R/L17R and L49R/L52R) with leucine-to-arginine replacements in the N-terminal conserved region (which we termed the Solo domain) and analyzed their K18-binding activities. These mutations markedly decreased the K18-binding ability of the N-terminal fragment (residues 1-329) of Solo but had no apparent effect on the K18-binding ability of full-length (FL) Solo. When expressed in cultured cells, wild-type Solo-FL showed a unique punctate localization near the ventral surface of cells and caused the reinforcement of actin filaments. In contrast, despite retaining the K18-binding ability, the L14R/L17R and L49R/L52R mutants of Solo-FL were diffusely distributed in the cytoplasm and barely induced actin cytoskeletal reinforcement. Furthermore, wild-type Solo-FL promoted traction force generation against extracellular matrices and tensional force-induced stress fiber reinforcement, but its L14R/L17R and L49R/L52R mutants did not. These results suggest that the K18-binding ability of the N-terminal Solo domain is critical for the ventral localization of Solo and its function in regulating mechanotransduction.

Isolated adrenocorticotropic hormone deficiency and thyroiditis associated with nivolumab therapy in a patient with advanced lung adenocarcinoma: a case report and review of the literature.

INTRODUCTION: Immune checkpoint inhibitors are a promising class of anticancer drugs. The clinical benefits afforded by immune checkpoint inhibitors can be accompanied by immune-related adverse events that affect multiple organs, and endocrine immune-related adverse events include thyroiditis and hypophysitis. Hypophysitis is less frequent and has a less severe clinical presentation in patients treated with other immune checkpoint inhibitors, such as nivolumab, pembrolizumab, and atezolizumab, than in those treated with ipilimumab. However, studies have described isolated adrenocorticotropic hormone deficiency cases associated with nivolumab, pembrolizumab, and atezolizumab therapy, most of which occurred during the course of immune checkpoint inhibitor therapy. We report a rare case of patient with isolated adrenocorticotropic hormone deficiency that occurred after nivolumab therapy. CASE PRESENTATION: A 69-year-old Japanese woman with advanced lung adenocarcinoma developed painless thyroiditis with transient elevations of serum thyroid hormones during 3 months of cancer treatment with nivolumab and began thyroid hormone replacement therapy for subsequent primary hypothyroidism. Four months after nivolumab therapy was discontinued, she developed isolated adrenocorticotropic hormone deficiency; corticosteroid replacement therapy relieved her secondary adrenal insufficiency symptoms, such as anorexia and fatigue. Human leukocyte antigen typing revealed the presence of DRB1*04:05-DQB1*04:01-DQA1*03:03 and DRB1*09:01-DQB1*03:03-DQA1*03:02 haplotypes, which increase susceptibility to autoimmune polyendocrine syndrome associated with thyroid and pituitary disorders in the Japanese population. CONCLUSIONS: Our patient developed thyroiditis during cancer treatment with nivolumab and subsequently exhibited isolated adrenocorticotropic hormone deficiency 4 months after discontinuing the drug. Administration of nivolumab in combination with a genetic predisposition to polyglandular autoimmunity probably caused both the thyroiditis and hypophysitis, resulting in primary hypothyroidism and isolated adrenocorticotropic hormone deficiency, respectively, in our patient. The present case highlights the need for physicians to be aware that endocrine immune-related adverse events, including hypophysitis, can occur more than several months after discontinuing a drug.

Role of IL-15 in interstitial lung diseases in amyopathic dermatomyositis with anti-MDA-5 antibody.

BACKGROUND: Anti-MDA-5 antibody is closely associated with interstitial lung disease (ILD) in amyopathic dermatomyositis (ADM). Patients with ADM with anti-MDA-5 antibody sometimes develop fatal ILD in spite of intensive immunosuppressive therapy. However, an initial decrease after treatment in anti-MDA-5 antibody titers may not be predictive of subsequent better survival of the disease. METHODS: To clarify immunoregulatory features of deadly ILD in ADM with the anti-MDA-5 antibody, we retrospectively examined clinical records of consecutive patients with anti-MDA-5 antibody positive ADM-ILD with preserved serum since 2000. Serum cytokine/growth factor (GF) protein concentration was measured using a cytokine panel analysis. We compared concentrations of each cytokine/GF between survivors and non-survivors and further examined changes in cytokines/GF levels during treatment in some patients. RESULTS: Twenty-six patients were enrolled in the study. Nine out of 26 patients did not respond to intensive immunosuppressive therapy and died due to respiratory failure. We compared cytokine/GF concentrations and found that serum IL-15 before treatment was significantly elevated in non-survivors than in survivors (p < 0.05). 11 out of 17 responders and 6 of 9 dead patients had preserved serum taken more than one time. We then calculated rates of change per day (slopes) in each cytokine/GF concentration. Comparison of slopes of cytokine/GF protein over the treatment duration showed that the slopes in non-survivors were significantly increased in IL-10 and IL-15 (p < 0.01). CONCLUSIONS: IL-15, as well as IL-10, may play a key role in the progression of the patients with ADM-ILD with anti-MDA-5 antibody positive.

Legionella Pneumonia Complicated with Acquired Fanconi Syndrome.

Legionella pneumonia is occasionally accompanied by renal complications; however, the cause of this remains unknown. We herein report a 70-year-old Japanese man with Legionella pneumonia who presented with hyponatremia, hypophosphatemia, and hypouricemia. The levels of urinary ß2-microglobulin and N-acetyl-ß-D-glucosaminidase were remarkably high, indicating severe renal tubular damage. The presence of glycosuria and aminoaciduria as well as increased fractional excretion of uric acid and decreased tubular reabsorption of phosphate indicated that the patient's condition was complicated with Fanconi syndrome. After antimicrobial therapy, the electrolyte abnormalities and renal tubular damage were completely resolved.

Bevacizumab-induced Aortic Arterial Thrombosis.

A 65-year-old man was diagnosed with advanced non-small, non-squamous lung cancer. He was treated with chemotherapy containing bevacizumab as well as cisplatin and pemetrexed. After 2 courses of treatment, computed tomography revealed that his abdominal aortic artery was almost occluded by a thrombus; however, he had no ischemic symptoms. Heparin infusion and warfarin reduced the size of the arterial thrombus and the patient was subsequently treated with chemotherapy without bevacizumab. No thrombotic events occurred during the subsequent treatment. We later noticed a small organized abdominal arterial clot and calcification on a computed tomography scan taken before bevacizumab treatment. Atherosclerotic changes should be evaluated before the administration of bevacizumab.

Solo and Keratin Filaments Regulate Epithelial Tubule Morphology.

Epithelial tubules, consisting of the epithelial cell sheet with a central lumen, are the basic structure of many organs. Mechanical forces play an important role in epithelial tubulogenesis; however, little is known about the mechanisms controlling the mechanical forces during epithelial tubule morphogenesis. Solo (also known as ARHGEF40) is a RhoA-targeting guanine-nucleotide exchange factor that is involved in mechanical force-induced RhoA activation and stress fiber formation. Solo binds to keratin-8/keratin-18 (K8/K18) filaments, and this interaction plays a crucial role in mechanotransduction. In this study, we examined the roles of Solo and K8/K18 filaments in epithelial tubulogenesis using MDCK cells cultured in 3D collagen gels. Knockdown of either Solo or K18 resulted in rounder tubules with increased lumen size, indicating that Solo and K8/K18 filaments play critical roles in forming the elongated morphology of epithelial tubules. Moreover, knockdown of Solo or K18 decreased the level of diphosphorylated myosin light chain (a marker of contractile force) at the luminal and outer surfaces of tubules, suggesting that Solo and K8/K18 filaments are involved in the generation of the myosin II-mediated contractile force during epithelial tubule morphogenesis. In addition, K18 filaments were normally oriented along the long axis of the tubule, but knockdown of Solo perturbed their orientation. These results suggest that Solo plays crucial roles in forming the elongated morphology of epithelial tubules and in regulating myosin II activity and K18 filament organization during epithelial tubule formation.Key words: epithelial tubulogenesis, Solo, keratin, Rho-GEF, myosin.

Solo, a RhoA-targeting guanine nucleotide exchange factor, is critical for hemidesmosome formation and acinar development in epithelial cells.

Cell-substrate adhesions are essential for various physiological processes, including embryonic development and maintenance of organ functions. Hemidesmosomes (HDs) are multiprotein complexes that attach epithelial cells to the basement membrane. Formation and remodeling of HDs are dependent on the surrounding mechanical environment; however, the upstream signaling mechanisms are not well understood. We recently reported that Solo (also known as ARHGEF40), a guanine nucleotide exchange factor targeting RhoA, binds to keratin8/18 (K8/K18) intermediate filaments, and that their interaction is important for force-induced actin and keratin cytoskeletal reorganization. In this study, we show that Solo co-precipitates with an HD protein, ß4-integrin. Co-precipitation assays revealed that the central region (amino acids 330-1057) of Solo binds to the C-terminal region (1451-1752) of ß4-integrin. Knockdown of Solo significantly suppressed HD formation in MCF10A mammary epithelial cells. Similarly, knockdown of K18 or treatment with Y-27632, a specific inhibitor of Rho-associated kinase (ROCK), suppressed HD formation. As Solo knockdown or Y-27632 treatment is known to disorganize K8/K18 filaments, these results suggest that Solo is involved in HD formation by regulating K8/K18 filament organization via the RhoA-ROCK signaling pathway. We also showed that knockdown of Solo impairs acinar formation in MCF10A cells cultured in 3D Matrigel. In addition, Solo accumulated at the site of traction force generation in 2D-cultured MCF10A cells. Taken together, these results suggest that Solo plays a crucial role in HD formation and acinar development in epithelial cells by regulating mechanical force-induced RhoA activation and keratin filament organization.

Isolated Adrenocorticotropin Deficiency due to Nivolumab-induced Hypophysitis in a Patient with Advanced Lung Adenocarcinoma: A Case Report and Literature Review.

A 63-year-old Japanese woman with advanced lung adenocarcinoma developed isolated adrenocorticotropin deficiency caused by immune checkpoint inhibitor (ICI)-related hypophysitis following 8 months of nivolumab therapy. Prompt corticosteroid replacement therapy effectively relieved her secondary adrenal insufficiency symptoms and allowed her to pursue nivolumab therapy, which had been effective for the control of lung adenocarcinoma. Human leukocyte antigen (HLA) typing revealed the presence of the DRB1*04:05-DQA1*03:03-DQB1*04:01 haplotype, which is associated with susceptibility to autoimmune polyglandular syndrome with pituitary disorder in the Japanese population. This case suggests that genetic factors, such as HLA, contribute to the development of endocrinopathies induced by ICIs.

Acute hypopituitarism associated with periorbital swelling and cardiac dysfunction in a patient with pituitary tumor apoplexy: a case report.

BACKGROUND: Pituitary tumor apoplexy is a rare clinical syndrome caused by acute hemorrhage or infarction in a preexisting pituitary adenoma. It typically manifests as an acute episode of headache, visual disturbance, mental status changes, cranial nerve palsy, and endocrine pituitary dysfunction. However, not all patients present with classical symptoms, so it is pertinent to appreciate the clinical spectrum of pituitary tumor apoplexy presentation. We report an unusual case of a patient with pituitary tumor apoplexy who presented with periorbital edema associated with hypopituitarism. CASE PRESENTATION: An 83-year-old Japanese man developed acute anterior hypopituitarism; he showed anorexia, fatigue, lethargy, severe bilateral periorbital edema, and mild cardiac dysfunction in the absence of headache, visual disturbance, altered mental status, and cranial nerve palsy. Magnetic resonance imaging showed a 2.5-cm pituitary tumor containing a mixed pattern of solid and liquid components indicating pituitary tumor apoplexy due to hemorrhage in a preexisting pituitary adenoma. Replacement therapy with oral hydrocortisone and levothyroxine relieved his symptoms of central adrenal insufficiency, central hypothyroidism, periorbital edema, and cardiac dysfunction. CONCLUSIONS: Common causes of periorbital edema include infections, inflammation, trauma, allergy, kidney or cardiac dysfunction, and endocrine disorders such as primary hypothyroidism. In the present case, the patient's acute central hypothyroidism was probably involved in the development of both periorbital edema and cardiac dysfunction. The present case highlights the need for physicians to consider periorbital edema as an unusual predominant manifestation of pituitary tumor apoplexy.

Generalized Status Epilepticus in a Patient with Acute-onset Type 1 Diabetes Mellitus Associated with Severe Kidney Dysfunction: A Case Report and Literature Review.

A 65-year-old Japanese man with advanced chronic kidney disease (CKD) developed acute-onset type 1 diabetes mellitus (T1D) that was associated with severe acute kidney injury and was manifested by generalized tonic-clonic status epilepticus. His seizures resolved without recurrence after correcting the diabetic ketoacidosis. Although hyperglycemia is an important cause of acute symptomatic seizure (ASS), patients with ketotic hyperglycemia develop ASS less frequently. In this T1D case with CKD, severe hyperglycemia in conjunction with other metabolic insults, such as uremia, hyponatremia, and hypocalcemia, probably provoked his seizure despite the severe ketonemia.