Comorbid functional dyspepsia reflects IL-33-mediated airway neuronal dysfunction in asthma.

BACKGROUND: Neuronal dysfunction is implicated in the pathophysiology of asthma and functional dyspepsia (FD). However, the relationship between these diseases remains unclear. OBJECTIVE: This study aimed to clarify the clinical implications of comorbid FD in asthma and to explore the unified pathway between asthma and FD by focusing on airway neuronal dysfunction. METHODS: Clinical indices and biomarkers, including capsaicin cough sensitivity (C-CS), were compared between patients with asthma with and without FD. C-CS was determined based on the capsaicin concentration that induced at least two (C2) or five coughs (C5). Additionally, the associations of airway inflammation with airway innervation and gastrointestinal motility were evaluated in mouse models of type 2 airway inflammation. RESULTS: Patients with asthma with FD had worse asthma control and cough severity and lower C2 and C5 thresholds than those without FD. The severity of FD symptoms was negatively correlated with C2 and C5 thresholds. FD and poor asthma control were predictors of heightened C-CS (defined as C5 of ≤ 2.44 µM) in asthma. A mouse model of papain-induced airway inflammation developed airway hyperinnervation and gastrointestinal dysmotility, and both pathologies were ameliorated by an anti-interleukin (IL)-33 antibody. Moreover, papain-induced gastrointestinal dysmotility was mitigated by silencing the airway sensory neurons using QX-314, a sodium channel blocker. Furthermore, sputum IL-33 levels were significantly elevated in patients with asthma with FD or heightened C-CS compared with those in their counterparts. CONCLUSION: FD is significantly associated with airway neuronal dysfunction in asthma. IL-33-mediated airway neuronal dysfunction may contribute to the interaction between asthma and FD.

Clinical Impact of Proton Pump Inhibitor and Potassium-Competitive Acid Blocker for Predicting the Curability of Endoscopic Resection in Ulcerative Early Gastric Cancer.

INTRODUCTION: Endoscopic diagnosis is essential for predicting the curability of early gastric cancer (EGC; R0 resection) before treatment, but the relationship between ulcerative lesions and clinical outcomes remains unclear. We aimed to investigate the effect of proton pump inhibitor (PPI) or potassium-competitive acid blocker (P-CAB) on the morphological changes of ulcerative EGCs and its relevance to the clinical outcomes. METHODS: Altogether, 143 patients with differentiated ulcerative EGC that were resected by endoscopic submucosal dissection were retrospectively identified and divided into the following two cohorts depending on their PPI/P-CAB administration status: PPI/P-CAB (n = 76) and non-PPI/P-CAB (n = 67) cohorts. Furthermore, in each cohort, the patients were further divided into the improved and unimproved subgroups based on the ulcerative changes. RESULTS: In the PPI/P-CAB cohort, the deep submucosal invasion and lymphovascular invasion rates were significantly higher in the unimproved subgroup than in the improved subgroup, resulting in a significantly lower R0 resection rate. Contrarily, no significant differences were found between the two subgroups in the non-PPI/P-CAB cohort. The significance of PPI/P-CAB administration was observed only in the ulcerative EGCs with open-type atrophy (R0 resection rate; improved vs. unimproved, 90.9% vs. 48.0%, p = 0.001). When the finding of improved ulcer with PPI/P-CAB administration was used as the indication of endoscopic resection in ulcerative EGCs with open-type atrophy, high sensitivity (78.9%) and accuracy (76.3%) rates for the curability were observed, which were higher than those of conventional endoscopic diagnosis alone (p = 0.021). CONCLUSION: PPI or P-CAB administration might contribute to the potential selection of ulcerative EGCs, enabling endoscopic curative resection.

Reovirus combined with a STING agonist enhances anti-tumor immunity in a mouse model of colorectal cancer.

Reovirus, a naturally occurring oncolytic virus, initiates the lysis of tumor cells while simultaneously releasing tumor antigens or proapoptotic cytokines in the tumor microenvironment to augment anticancer immunity. However, reovirus has developed a strategy to evade antiviral immunity via its inhibitory effect on interferon production, which negatively affects the induction of antitumor immune responses. The mammalian adaptor protein Stimulator of Interferon Genes (STING) was identified as a key regulator that orchestrates immune responses by sensing cytosolic DNA derived from pathogens or tumors, resulting in the production of type I interferon. Recent studies reported the role of STING in innate immune responses to RNA viruses leading to the restriction of RNA virus replication. In the current study, we found that reovirus had a reciprocal reaction with a STING agonist regarding type I interferon responses in vitro; however, we found that the combination of reovirus and STING agonist enhanced anti-tumor immunity by enhancing cytotoxic T cell trafficking into tumors, leading to significant tumor regression and survival benefit in a syngeneic colorectal cancer model. Our data indicate the combination of reovirus and a STING agonist to enhance inflammation in the tumor microenvironment might be a strategy to improve oncolytic reovirus immunotherapy.

The impact of tube replacement timing during LCIG therapy on PEG-J associated adverse events: a retrospective multicenter observational study.

BACKGROUND: Levodopa-carbidopa intestinal gel (LCIG) treatment, a unique drug delivery system for patients with advanced Parkinson's disease (PD), is covered by health insurance in Japan since September 2016. Various LCIG procedure/device-associated adverse events (AEs) have been reported; however, reports on their treatment have been limited. This is the first multicenter study to clarify the frequency and timing of device-related AEs. METHODS: Between September 2016 and December 2018, 104 patients introduced to the LCIG treatment for advanced PD in 11 hospitals were included. The patients' characteristics, AEs incidence, AEs time, and tube exchange time were investigated. RESULTS: The median follow-up period was 21.5 months. Minor AE cases were 29.4%, whereas major AE cases were 43.1%. Majority of major AEs (n = 55, 94.8%) were managed with endoscopic treatment, such as tube exchange. Few severe AEs required surgical treatment (n =3, 5.2%). The mean (range) exposure to percutaneous endoscopic gastrojejunostomy (PEG-J) was 14.7 (0-33) months. One year after the LCIG treatment introduction, 55 patients (54.0%) retained the original PEG-J tube. The mean PEG-J tube exchange time was 10.8 ± 7.0 months in all patients, 11.6 ± 4.7 and 10.5 ± 7.7 months in patients with scheduled exchange and who underwent exchange due to AEs, respectively. CONCLUSIONS: Some device-related AEs occurred during the LCIG treatment; however, only few were serious, most of which could be treated with simple procedures or tube replacement with endoscopy. Therefore, the LCIG treatment is feasible and safe and is a unique treatment option for PD, requiring endoscopists' understanding and cooperation.

Integrated genetic and epigenetic analysis of cancer-related genes in non-ampullary duodenal adenomas and intramucosal adenocarcinomas.

The molecular and clinical characteristics of non-ampullary duodenal adenomas and intramucosal adenocarcinomas are not fully understood because they are rare. To clarify these characteristics, we performed genetic and epigenetic analysis of cancer-related genes in these lesions. One hundred and seven non-ampullary duodenal adenomas and intramucosal adenocarcinomas, including 100 small intestinal-type tumors (90 adenomas and 10 intramucosal adenocarcinomas) and 7 gastric-type tumors (2 pyloric gland adenomas and 5 intramucosal adenocarcinomas), were investigated. Using bisulfite pyrosequencing, we assessed the methylation status of CpG island methylator phenotype (CIMP) markers and MLH1. Then using next-generation sequencing, we performed targeted exome sequence analysis within 75 cancer-related genes in 102 lesions. There were significant differences in the clinicopathological and molecular variables between small intestinal- and gastric-type tumors, which suggests the presence of at least two separate carcinogenic pathways in non-ampullary duodenal adenocarcinomas. The prevalence of CIMP-positive lesions was higher in intramucosal adenocarcinomas than in adenomas. Thus, concurrent hypermethylation of multiple CpG islands is likely associated with development of non-ampullary duodenal intramucosal adenocarcinomas. Mutation analysis showed that APC was the most frequently mutated gene in these lesions (56/102; 55%), followed by KRAS (13/102; 13%), LRP1B (10/102; 10%), GNAS (8/102; 8%), ERBB3 (7/102; 7%), and RNF43 (6/102; 6%). Additionally, the high prevalence of diffuse or focal nuclear ß-catenin accumulation (87/102; 85%) as well as mutations of WNT pathway components (60/102; 59%) indicates the importance of WNT signaling to the initiation of duodenal adenomas. The higher than previously reported frequency of APC gene mutations in small bowel adenocarcinomas as well as the difference in the APC mutation distributions between small intestinal-type adenomas and intramucosal adenocarcinomas may indicate that the adenoma-carcinoma sequence has only limited involvement in duodenal carcinogenesis. © 2020 The Authors. The Journal of Pathology published by John Wiley & Sons, Ltd. on behalf of The Pathological Society of Great Britain and Ireland.

Relationship between Immunophenotype and Clinicopathological Findings for Superficial Nonampullary Duodenal Epithelial Tumor.

INTRODUCTION: The natural history and prognosis of superficial nonampullary duodenal epithelial tumors (SNADETs) remain uncertain. We elucidated the relationship between immunophenotype and clinicopathological features. MATERIALS AND METHODS: A total of 98 SNADETs were divided into 3 groups according to immunohistochemical findings: gastric phenotype (G type), gastrointestinal phenotype (GI type), and intestinal phenotype (I type). Cellular dysplasia was divided into low-grade dysplasia and high-grade dysplasia/adenocarcinoma (≥HGD). White opaque substance (WOS) deposition was categorized into diffuse WOS, partial WOS, and no WOS, based on endoscopic findings. RESULTS: Of the 98 SNADETs, 4 lesions (4.1%) were G type, 32 lesions (32.7%) were GI type, and 62 lesions (63.2%) were I type. All G-type SNADETs were located in the oral side of the papilla including the bulb, and the rate of bulbar lesions was significantly higher in the G type than in the GI and I types (p = 0.004). The most frequent type of WOS was no WOS (4/4, 100%) for G type, partial WOS (19/32, 59.4%) for GI type, and diffuse WOS (34/62, 54.8%) for I type (p < 0.001), and loss of intestinal character was significantly correlated with WOS deficiency. GI/I-type SNADETs with partial or no WOS and G-type SNADETs were associated with ≥HGD. Additionally, the frequency of ≥HGD lesion was significantly higher in the CD10-negative group than in the CD10-positive group (57.1 vs. 19.8%, p = 0.043). CONCLUSION: Pathological intestinal character was correlated with the presence of WOS, and CD10 loss was associated with malignant potential of SNADETs.

Effect of anti-reflux treatment on gastroesophageal reflux-associated chronic cough: Implications of neurogenic and neutrophilic inflammation.

Objective: Gastroesophageal reflux disease (GERD) is an important cause of chronic cough. Substance P (SP) has been implicated in the pathophysiology of cough. Proton pump inhibitors (PPIs) and prokinetic agents are the current treatment for GER-associated cough. The aim was to evaluate the effects of anti-reflux treatment and its associations with cellular and neurogenic inflammation.Methods: Thirty-seven patients with GER-associated cough suspected based on characteristic symptoms such as heartburn and worsening of cough by phonation and rising were recruited. A PPI, rabeprazole 20 mg daily, and a prokinetic agent, itopride 50 mg t.i.d., were administered for 4 weeks in a prospective, observational manner. Before and after treatment, subjective cough measures [visual analog scale (VAS) and the Japanese version of the Leicester Cough Questionnaire (J-LCQ)], the modified frequency scale for the symptoms of GERD [FSSG, consisting of 2 domains: acid-reflux (AR) and functional dyspepsia symptoms], sputum and plasma SP levels, and sputum cell differentials were examined. Patients with good response to treatment [Δ (decrease of) VAS >15 mm; n = 21) were compared with poor responders (ΔVAS ≤15 mm).Results: Anti-reflux treatment significantly improved the cough VAS, J-LCQ, and AR symptoms, and ΔVAS and ΔAR were significantly correlated. Decreases of plasma and sputum SP levels and sputum neutrophil counts were significantly greater in responders than in poor responders. Both baseline values and post-treatment changes of plasma SP and sputum neutrophils were significantly correlated for all patients.Conclusions: Successful treatment of GER-associated cough may be associated with the attenuation of neurogenic and neutrophilic inflammation.

Questionnaire-Based Survey on Epidemiology of Functional Gastrointestinal Disorders and Current Status of Gastrointestinal Motility Testing in Asian Countries.

BACKGROUND/AIMS: Functional gastrointestinal disorders (FGIDs) are diagnosed and classified using the latest Rome IV criteria, released in 2016. Epidemiology of FGID diagnosed by the Rome IV criteria and current clinical application of gastrointestinal motility testing in Asian countries are not well known. The aims of this survey are to elucidate the present situation of epidemiology and diagnostic tests of FGID in clinical practice in some East and Southeast Asian countries. METHODS: The questionnaire focusing on current situation of FGID diagnosis and gastrointestinal motility testing was distributed to members of the International Gastroenterology Consensus Symposium study group and collected to be analyzed. RESULTS: The prevalence rates of subtypes of both functional dyspepsia (FD) and irritable bowel syndrome (IBS) are relatively similar in all Asian countries. In these countries, most patients underwent both upper endoscopy and Helicobacter pylori test to diagnose FD. Colonoscopy was also frequently performed to diagnose IBS and chronic constipation. The frequency of gastrointestinal motility testing to examine gastric emptying and colonic transit time varied among Asian countries. CONCLUSIONS: This survey revealed epidemiology of FGIDs and current status of gastrointestinal motility testing in some East and Southeast Asian countries.

Cullin-3/KCTD10 complex is essential for K27-polyubiquitination of EIF3D in human hepatocellular carcinoma HepG2 cells.

Eukaryotic translation initiation factor 3 subunit D (EIF3D) binds to the 5'-cap of specific mRNAs, initiating their translation into polypeptides. From a pathological standpoint, EIF3D has been observed to be essential for cell growth in various cancer types, and cancer patients with high EIF3D mRNA levels exhibit poor prognosis, indicating involvement of EIF3D in oncogenesis. In this study, we found, by mass spectrometry, that Cullin-3 (CUL3)/KCTD10 ubiquitin (Ub) ligase forms a complex with EIF3D. We also demonstrated that EIF3D is K27-polyubiquitinated at the lysine 153 and 275 residues in a KCTD10-dependent manner in human hepatocellular carcinoma HepG2 cells. Similar to other cancers, high expression of EIF3D significantly correlated with poor prognosis in hepatocellular carcinoma patients, and depletion of EIF3D drastically suppressed HepG2 cell proliferation. These results indicate that EIF3D is a novel substrate of CUL3/KCTD10 Ub ligase and suggest involvement of K27-polyubiquitinated EIF3D in the development of hepatocellular carcinoma.

Excellent antitumor effects for gastrointestinal cancers using photodynamic therapy with a novel glucose conjugated chlorin e6.

BACKGROUND: Photodynamic therapy (PDT) exploits the reaction between photosensitizer and irradiated light to generate potentially therapeutic reactive oxygen species such as singlet oxygen in cancer cells. We have reported several sugar-conjugated chlorins that express stronger antitumor effects in PDT than talaporfin sodium (TS), a second-generation photosensitizer clinically used in Japan. In this study, we developed a novel glucose-conjugated chlorin e6 (G-chlorin e6) and evaluated its antitumor effects. METHODS: G-chlorin e6 was synthesized with a core photosensitizer chlorin e6 conjugated to glucose. We measured the half maximal inhibitory concentration (IC50) to compare the PDT effects of G-chlorin e6 and TS, and flow cytometry was performed to examine the accumulation of G-chlorin e6 in cancer cells. We also compared the accumulation of G-chlorin e6 between normal immortalized esophageal epithelial cells and esophageal cancer cells. Antitumor effects of G-chlorin e6 PDT were finally analyzed in allograft tumor mouse models. RESULTS: PDT in vitro using G-chlorin e6 elicited 9, 000-34,000 times stronger antitumor effects than TS, and there was 70-190 times more G-chlorin e6 accumulated than TS by flow cytometry. G-chlorin e6 accumulated more selectively in esophageal cancer cells than in esophageal immortalized epithelial cells, and in an allograft model, PDT with G-chlorin e6 showed very strong antitumor effects and a 40% complete response (CR) rate. CONCLUSIONS: G-chlorin e6 showed excellent tumor selectivity, and PDT using G-chlorin e6 revealed the strongest anti-tumor effects among all sugar-conjugated chlorins that we have studied. G-chlorin e6 is considered to be the best photosensitizer for next-generation PDT.

Neddylated Cullin 3 is required for vascular endothelial-cadherin-mediated endothelial barrier function.

Vascular endothelial (VE)-cadherin, a major endothelial adhesion molecule, regulates vascular permeability, and increased vascular permeability has been observed in several cancers. The aim of this study was to elucidate the role of the NEDD8-Cullin E3 ligase, in maintaining barrier permeability. To this end, we investigated the effects of the inhibition of Cullin E3 ligases, by using inhibitors and knockdown techniques in HUVECs. Furthermore, we analyzed the mRNA and protein levels of the ligases by quantitative RT-PCR and Western blotting, respectively. The results revealed that NEDD8-conjugated Cullin 3 is required for VE-cadherin-mediated endothelial barrier functions. Treatment of HUVECs with MLN4924, a chemical inhibitor of the NEDD8-activating enzyme, led to high vascular permeability due to impaired cell-cell contact. Similar results were obtained when HUVECs were treated with siRNA directed against Cullin 3, one of the target substrates of NEDD8. Immunocytochemical staining showed that both treatments equally depleted VE-cadherin protein localized at the cell-cell borders. However, quantitative RT-PCR showed that there was no significant difference in the VE-cadherin mRNA levels between the treatment and control groups. In addition, cycloheximide chase assay revealed that the half-life of VE-cadherin protein was dramatically reduced by Cullin 3 depletion. Together, these findings suggest that neddylated Cullin 3 plays a crucial role in endothelial cell barrier function by regulating VE-cadherin.

A multicenter randomized trial comparing rabeprazole and itopride in patients with functional dyspepsia in Japan: the NAGOYA study.

The aims of this study were to compare the therapeutic effects of a proton pump inhibitor (PPI), rabeprazole (RPZ), and a prokinetic agent, itopride (ITO), and to investigate the role of PPI in the treatment strategy for Japanese functional dyspepsia (FD) patients. We randomly assigned 134 patients diagnosed by Rome III criteria to 4 weeks treatment with RPZ 10 mg/day (n = 69) or ITO 150 mg/day (n = 65). Dyspeptic symptoms were evaluated using FD scores at baseline and after 1, 2 and 4 weeks of treatment. We also divided subjects into predominantly epigastric pain syndrome (EPS) or postprandial distress syndrome (PDS), and evaluated the efficacy of RPZ and ITO respectively. RPZ showed a significant decrease in the Rate of Change (RC) in FD score within 1 week, which was maintained until after 4 weeks, with RPZ a significant effect compared with ITO at all evaluation points. In addition, RPZ showed a significant decrease in FD score in subjects with both EPS and PDS, whereas a significant decrease in the RC with ITO was only shown in those with predominant PDS. Acid-suppressive therapy with RPZ is useful for PDS as well EPS in Japanese FD patients (UMIN Clinical Trials Registry number: UMIN 000013962).

Questionnaire-Based Survey on Diagnostic and Therapeutic Endoscopies and H. pylori Eradication for Elderly Patients in East Asian Countries.

BACKGROUND: Gastrointestinal endoscopy and Helicobacter pylori(H. pylori) eradication therapy are commonly performed even among the elderly population. The aim of this study was to understand the way endoscopists viewed the application of endoscopy and H. pylori eradication in the elderly of East Asian countries. METHODS: Self-administered questionnaires containing 13 questions on endoscopy and H. pylori eradication in the elderly were distributed to major institutions in Japan, South Korea, China, Indonesia, and the Philippines. RESULTS: Two hundred and fifteen endoscopists (111 in Japan, 39 in China, 24 in Korea, 21 in Indonesia, and 20 in the Philippines) participated in this study. In the institutions where these endoscopists were associated, around 50% of patients undergoing endoscopy were above the age of 60 years. The participating endoscopists indicated that the necessity of screening esophagogastroduodenoscopy and colonoscopy was lower in populations aged over 81 than the other age groups. They hesitated to perform therapeutic endoscopy, such as endoscopic submucosal dissection or endoscopic retrograde cholangiopancreatography, more often in patients over 85. They also hesitated to perform H. pylori eradication in patients aged over 81, especially in Japan. CONCLUSION: Endoscopists had significantly different attitudes regarding the indications for screening or therapeutic endoscopy and H. pylori eradication therapy in younger and elderly populations in East Asian countries.

Persistent reflux symptoms cause anxiety, depression, and mental health and sleep disorders in gastroesophageal reflux disease patients.

Some patients with gastroesophageal reflux disease experience persistent reflux symptoms despite proton pump inhibitor therapy. These symptoms reduce their health-related quality of life. Our aims were to evaluate the relationship between proton pump inhibitor efficacy and health-related quality of life and to evaluate predictive factors affecting treatment response in Japanese patients. Using the gastroesophageal reflux disease questionnaire, 145 gastroesophageal reflux disease patients undergoing proton pump inhibitor therapy were evaluated and classified as responders or partial-responders. Their health-related quality of life was then evaluated using the 8-item Short Form Health Survey, the Pittsburgh Sleep Quality Index, and the Hospital Anxiety and Depression Scale questionnaires. Sixty-nine patients (47.6%) were partial responders. These patients had significantly lower scores than responders in 5/8 subscales and in the mental health component summary of the 8-item Short Form Health Survey. Partial responders had significantly higher Pittsburgh Sleep Quality Index and Hospital Anxiety and Depression Scale scores, including anxiety and depression scores, than those of responders. Non-erosive reflux disease and double proton pump inhibitor doses were predictive factors of partial responders. Persistent reflux symptoms, despite proton pump inhibitor therapy, caused mental health disorders, sleep disorders, and psychological distress in Japanese gastroesophageal reflux disease patients.

[Renal thrombotic microangiopathy and antiphospholipid syndrome nephropathy in a patient with lupus nephritis].

The patient was a 48-year-old Japanese woman diagnosed as having systemic lupus erythematosus at the age of 21 years when she presented with fever and an erythematous skin rash on her face and extremities. Prednisolone was initiated at that time. Thirteen days before admission to our hospital, she was referred to us by her family physician. Upon admission, blood tests showed pancytopenia, hypocomplementemia, and renal dysfunction, as well as the presence of lupus anticoagulant. Urinalysis showed abundant proteinuria and heavy microscopic hematuria. After performing a renal biopsy, we initiated immunosuppressive therapy and an anticoagulant. On the 22nd hospital day, microangiopathic hemolytic anemia appeared with the progression of thrombocytopenia and renal failure, and the patient subsequently underwent ten sessions of plasma exchange. After the commencement of the plasma exchange, her general condition improved. Her renal dysfunction, however, continued to progress, and hemodialysis was started on the 36th hospital day. The light microscopy showed severe endo- and extra-capillary proliferative glomerulonephritis with abundant crescents, and massive thrombi in the capillary lumen of the glomeruli. The arterioles contained occlusive hyaline materials. An immunofluorescence study showed granular staining of immunoglobulins and complements along the glomerular capillary wall. An electron microscopy examination revealed the presence of electron-dense deposits in the subepithelial and intramembranous areas of the glomeruli, but subendothelial deposits were absent. For cases with lupus nephritis (LN), immunosuppressive therapy based on corticosteroid remains the mainstay of treatment. However, immunosuppression alone may be insufficient when antiphospholipid antibody syndrome and thrombotic microangiopathy (TMA) are also present, and other treatment modalities including antiplatelet therapy, anticoagulation, and plasma exchange are likely to be necessary, as illustrated by the present case. Although the mechanism responsible for LN remains uncertain, we report a case of LN suggesting that TMA is associated with renal dysfunction.

Induction of ferroptosis by photodynamic therapy and enhancement of antitumor effect with ferroptosis inducers.

BACKGROUND: Photodynamic therapy (PDT) is an effective tumor treatment that involves the administration of a photosensitizer to generate cytotoxic 1O2 [reactive oxygen species (ROS)] from molecular oxygen that is produced from energy absorption following tumor irradiation at specific wavelengths. Ferroptosis is induced by the disruption of the glutathione peroxidase 4 (GPX4) antioxidant system, leading to lipid peroxidation. We hypothesized that talaporfin sodium-photodynamic therapy (TS-PDT)-generated ROS would lead to ferroptosis via accumulation of lipid peroxidation. METHODS: Cell viability assay in TS-PDT-treated cells in combination with a ferroptosis inhibitor (ferrostatin-1: Fer-1) or ferroptosis inducers (imidazole ketone erastin: IKE, Ras-selective lethal 3: RSL3) was performed. Accumulation of lipid peroxidation, GPX4 antioxidant system and cystine/glutamate antiporter (system xc-) activity in TS-PDT-treated cells was investigated. In xenograft mice, the antitumor effect of TS-PDT in combination with ferroptosis inducers (IKE or sorafenib) was examined. RESULTS: TS-PDT-induced cell death was partly suppressed by Fer-1 and accompanied by lipid peroxidation. TS-PDT combined with IKE or RSL3 enhanced the induction of cell death. TS-PDT inhibited cystine uptake activity via system xc-. In vivo, the combination of TS-PDT and ferroptosis inducers (IKE or sorafenib) reduced tumor volume. CONCLUSION: This study found that the mechanism underlying TS-PDT-induced ferroptosis constitutes direct lipid peroxidation by the generated ROS, and the inhibition of system xc-, and that the combination of a ferroptosis inducer with TS-PDT enhances the antitumor effect of TS-PDT. Our findings suggest that ferroptosis-inducing therapies combined with PDT may benefit cancer patients.

Metal-conjugated Maltotriose Chlorins as Novel Photosensitizers for Photodynamic Therapy.

BACKGROUND/AIM: Photodynamic therapy (PDT) is a relatively non-invasive anti-cancer therapy that employs a photosensitizer with a specific wavelength of light, causing a photochemical reaction that releases free radicals, thereby inducing tumor cell necrosis via oxidative stress. The oxygen molecule reaches the singlet excited state through efficient energy transfer from an excited triplet state of the photosensitizer. Heavy atoms are frequently introduced in photosensitizers for efficiently generating reactive oxygen species (ROS) in PDT, known as the heavy atom effect. However, metal-complexed photosensitizers often show low water-solubility. To overcome this limitation and produce ROS effectively, we focused on the better solubility of photosensitizers with heavy metals bound within the chlorin skeleton and conjugated with glucose in this study. MATERIALS AND METHODS: We established maltotriose (Mal3)-conjugation with heavy metallochlorins [M (Mal3-chlorin), M=Pt or Pd)] and evaluated its anti-tumor effect. RESULTS: M (Mal3-chlorin) showed effective ROS production and singlet oxygen induction. Consequently, these cytotoxic factors caused effective anti-tumor effects and induced morphological changes, followed by cell death in vitro. In a xenograft tumor mouse model, PDT with M (Mal3-chlorin) showed tumor growth suppression. CONCLUSION: M (Mal3-Chlorin) might be an excellent glucose-conjugated chlorin because of its strong anti-tumor PDT effect.

Osteopontin secreted from obese adipocytes enhances angiogenesis and promotes progression of pancreatic ductal adenocarcinoma in obesity.

PURPOSE: Obesity is a risk factor and poor prognostic factor for pancreatic ductal adenocarcinoma (PDAC), but the underlying mechanisms remain unclear. METHODS: PDAC cells and obese visceral adipocytes (O-Ad) derived from mice and humans were used to analyze interactions between the two cell types, and human microvascular endothelial cells were used for angiogenesis assay. A xenograft mouse model with subcutaneously injected PDAC cells was used for animal studies. The relationship between visceral fat and prognosis was analyzed using resected tissues from PDAC patients with and without obesity. RESULTS: Conditioned media (CM) from O-Ad significantly increased PDAC cell growth and migration and angiogenic capacity in both human and mice cells, and blocking osteopontin (OPN) in O-Ad canceled O-Ad-induced effects in both mouse and human cells. In addition, O-Ad directly increased the migratory and tube-forming capacities of endothelial cells, while blocking OPN canceled these effects. O-Ad increased AKT phosphorylation and VEGFA expression in both PDAC and endothelial cells, and OPN inhibition in O-Ad canceled those O-Ad-induced effects. In the xenograft model, PDAC tumor volume was significantly increased in obese mice compared with lean mice, whereas blocking OPN significantly inhibited obesity-accelerated tumor growth. OPN expression in adipose tissues adjacent to human PDAC tumor was significantly higher in obese patients than in non-obese patients. In PDAC patients with obesity, high OPN expression in adipose tissues was significantly associated with poor prognosis. CONCLUSION: Obese adipocytes trigger aggressive transformation in PDAC cells to induce PDAC progression and accelerate angiogenesis via OPN secretion.

Renal thrombotic microangiopathy in a patient with septic disseminated intravascular coagulation.

BACKGROUND: The mechanism for the development of thrombotic microangiopathy (TMA) during sepsis has only been partially elucidated. TMA is recognized as a disease caused by various factors, and may be involved in the emergence of organ damage in severe sepsis. Here we report a case of TMA that followed disseminated intravascular coagulation (DIC) due to severe infection in a patient with a reduced ADAMTS-13 activity level. CASE PRESENTATION: An 86-year-old Japanese woman was admitted to our hospital because of low back pain and fever. A careful evaluation led to a diagnosis of acute obstructive pyelonephritis due to a ureteral stone. Proteus mirabilis was isolated from both blood and urine cultures. The patient developed systemic inflammatory response syndrome and DIC, and was treated with antibiotics and daily continuous hemodiafiltration. Although infection and the coagulation abnormalities due to DIC were successfully controlled, renal failure persisted and her consciousness level deteriorated progressively in association with severe thrombocytopenia and microangiopathic hemolytic anemia. We therefore suspected the presence of TMA and started plasma exchange, which resulted in an impressive improvement in consciousness as well as the laboratory abnormalities. The ADAMTS-13 activity was 44% and the patient tested negative for the ADAMTS-13 inhibitor prior to the initiation of plasma exchange. A renal biopsy was performed to determine the etiology of acute renal injury, which revealed findings that were interpreted to be compatible with the sequelae of TMA. The follow-up studies performed after the successful treatment of TMA showed that her plasma ADAMTS-13 activity level remained persistently low. It is surmised that septic DIC occurring in the presence of preexisting reduced ADAMTS-13 activity have led to the development of secondary TMA in the present case. CONCLUSION: The present case suggests that TMA can be superimposed on sepsis-induced DIC, and plasma exchange is expected to be beneficial in such situations. Clinicians should consider the possibility of secondary TMA that follows sepsis-induced DIC in certain indicative clinical settings.

Anti-tumor immunity enhancement by photodynamic therapy with talaporfin sodium and anti-programmed death 1 antibody.

Photodynamic therapy (PDT) is a relatively non-invasive anti-cancer therapy that employs a photosensitizer with a specific wavelength of light irradiation. PDT induces direct cell killing and enhancement effects on tumor immunity, but its underlying mechanism remains unknown. Here, we perform a basic analysis of the anti-tumor effect of talaporfin sodium (TS)-PDT as well as its synergism with the immune checkpoint inhibitor anti-programmed death 1 (anti-PD-1) antibody. We estimate the cell death mechanism induced by TS-PDT and the induction of damage-associated molecular patterns (DAMPs) by TS-PDT in vitro. We establish a syngeneic mouse model of bilateral flank tumors and verify the enhancement of the abscopal effect on the non-irradiated side. TS-PDT induced apoptosis, necrosis, and autophagy-associated cell death in vitro. TS-PDT induced the release and/or expression of DAMPs in vitro. Tumor growth was inhibited in the TS-PDT and anti-PD-1 antibody combination group compared with other single-treatment or non-treatment groups in vivo. In summary, TS-PDT induces the release and/or expression of DAMPs, indicating that it activates innate immunity. PD-1 blockage enhances the anti-tumor immunity induced by TS-PDT. Thus, our results demonstrate that the combination of TS-PDT and anti-PD-1 antibody can potentially be used for anti-tumor therapy.