Development of a novel fluorogenic assay method for screening inhibitors of bovine leukemia virus protease and identification of mitorubrinic acid as an anti-BLV compound.

Bovine leukemia virus (BLV) causes enzootic bovine leukosis, a fatal cattle disease that leads to significant economic losses in the livestock industry. Currently, no effective BLV countermeasures exist, except testing and culling. In this study, we developed a high-throughput fluorogenic assay to evaluate the inhibitory activity of various compounds on BLV protease, an essential enzyme for viral replication. The developed assay method was used to screen a chemical library, and mitorubrinic acid was identified as a BLV protease inhibitor that exhibited stronger inhibitory activity than amprenavir. Additionally, the anti-BLV activity of both compounds was evaluated using a cell-based assay, and mitorubrinic acid was found to exhibit inhibitory activity without cytotoxicity. This study presents the first report of a natural inhibitor of BLV protease-mitorubrinic acid-a potential candidate for the development of anti-BLV drugs. The developed method can be used for high-throughput screening of large-scale chemical libraries.

Design and synthesis of versatile GSTP1-specific fluorogenic substrates for the highly sensitive detection of GSTP1 activity in living cells.

Pi-class glutathione S-transferase (GSTP1) is a detoxification enzyme that is highly expressed in various types of cancer cells and is a promising target for cancer imaging and therapy. Ps-TAc, an acetylated derivative of the GSTP1-specific fluorogenic substrate Ps-TG, is attracting attention as an effective GSTP1 fluorescent probe, and has been successfully used to visualize intracellular GSTP1 activity. Ps-TAc is a prodrug type fluorescent probe in which the phenolic hydroxyl group of Ps-TG is acetylated and thus is susceptible to nonspecific hydrolysis, potentially compromising its ability to detect GSTP1 activity. Here, we describe the development of a highly selective fluorogenic GSTP1 substrate that is membrane permeable and does not involve esterification and show its application to live-cell imaging and FACS analysis. We designed and synthesized several compounds with benzylsulfone substituents instead of the mesyl group of Ps-TG and tested their fluorescence activation by GSTP1 catalysis in vitro and in cellulo. Of the test compounds, Ps-TG3 was the most suitable for the visualization of intracellular GSTP1 activity because the signal from living cells increased significantly when MK-571, an inhibitor of multidrug resistance proteins (MRPs), was simultaneously loaded. The results obtained by co-loading Ps-TG3 and MK571 into GSTP1-nonexpressing cells suggest that Ps-TG3 can be a substrate for MRPs. The usefulness of Ps-TG3 was demonstrated by fluorescence imaging of several cancer cell cultures and FACS analysis of lymphoma cells. The results presented here suggest that Ps-TG3, in combination with MK571, is useful for visualizing and detecting intracellular GSTP1 activity in cancer cells that highly express GSTP1.

Pi-Class Glutathione S-transferase (GSTP1)-Selective Fluorescent Probes for Multicolour Imaging with Various Cancer-Associated Enzymes.

Pi-class glutathione S-transferase (GSTP1) is highly expressed in a wide variety of human cancer tissues compared to the corresponding normal counterpart. Therefore, GSTP1 is a potential target enzyme for overcoming resistance to chemotherapeutic agents or visualizing specific lesions such as cancer. Here, we present orange and red fluorescence-emitting probes selective for GSTP1. Carbofluorescein and TokyoMagenta fluorophores were modified with a previously described GSTP1-selective chromogenic compound to generate orange and red fluorescence probes, respectively. Of these probes, Ps-CF, the orange fluorescence-emitting probe, was confirmed to be highly specific for detecting GSTP1 exogenously or endogenously expressed in various cancer cells. Additionally, it was demonstrated that Ps-CF is applicable for the simultaneous detection of GSTP1 and another cancer-associated enzyme by using a green fluorescence emitting γ-glutamyl transpeptidase (GGT) probe. In conclusion, the fluorescent probes developed in this study enable the simultaneous detection of multiple tumour markers such as GSTP1 with other cancer-associated enzymes by concurrently using spectrally distinguished fluorescent probes, potentially broadening the scope of cancer detection.

Orbital Intravascular Natural Killer/T-cell Lymphoma: An Unusual Cause of Ocular Symptoms.

Orbital intravascular lymphoma is rare and typically of B-cell lineage. In this study, we report a patient who developed orbital lesions of intravascular natural killer/T-cell lymphoma (IVNKL), an extremely rare lymphoma. An 88-year-old man presented with rapidly progressive right vision loss and double vision. A neurological examination revealed that he had decreased visual acuity and severe oculomotor impairment in the right eye. Magnetic resonance imaging showed right-dominant, nonmass lesions in both orbits. No lesions were found in the lymph nodes, skin, or brain. The patient received immunosuppressive and antifungal therapy, but his clinical condition rapidly deteriorated, and he died of multiple organ failure. Autopsy revealed natural killer/T-cell lymphoma proliferation within the lumina of small blood vessels in multiple organs, including the ocular adnexa of the right orbit. These findings show that he was ultimately diagnosed with IVNKL. IVNKL could initially cause ocular symptoms due to the involvement of the ocular adnexa. Ocular involvements have not been described previously. Even if patients initially present with only ocular symptoms, IVNKL should be considered.

Hepatitis C virus relapse after successful treatment with direct-acting antivirals, followed by sarcomatous changes in hepatocellular carcinoma: a case report.

BACKGROUND: Combination therapy of interferon and ribavirin has traditionally been used to eradicate hepatitis C virus. The sustained virologic response achieved with interferon-related therapy is persistent, and late relapses after achieving sustained virologic response at 24 weeks using this therapy are reportedly rare (< 1%). In 2014, interferon-free therapy with direct-acting antivirals was developed, and the rate of sustained virologic response was improved. However, the persistence thereof remains uncertain, and the appropriate follow-up period for hepatitis C virus-positive patients is under discussion. CASE PRESENTATION: A 74-year-old Japanese man who had hepatitis C virus-related hepatocellular carcinoma and was successfully treated with radiofrequency ablation four times underwent direct-acting antiviral therapy with daclatasvir and asunaprevir; sustained virologic response at 24 weeks was confirmed. However, although he had no high risk factors for reinfection, hepatitis C virus ribonucleic acid was detected again 6 months after achieving sustained virologic response at 24 weeks. Moreover, he developed active hepatitis with an increased viral load. Five months after development of hepatitis, recurrent hepatocellular carcinoma emerged in segment II, where we had performed radiofrequency ablation 17 months previously. The recurrent hepatocellular carcinoma enlarged quite rapidly and induced multiple peritoneal disseminations and lung metastases. He died 3 months after the abrupt recurrence. A sarcomatous change in the hepatocellular carcinoma was identified during the autopsy. CONCLUSIONS: Although sustained virologic response at 24 weeks has generally been regarded to denote complete eradication of hepatitis C virus, we present a patient in whom hepatitis C virus recurred 6 months after achieving sustained virologic response at 24 weeks with direct-acting antiviral therapy. In addition, a sarcomatous change in hepatocellular carcinoma emerged 5 months after active hepatitis developed due to late hepatitis C virus relapse in this case. The sarcomatous change in hepatocellular carcinoma is generally thought to be related to anticancer therapies, such as radiofrequency ablation. However, in this case, late viral relapse and active hepatitis in addition to the previous radiofrequency ablation could have been the trigger. There may be a need for follow-up of hepatitis C virus ribonucleic acid beyond sustained virologic response at 24 weeks with direct-acting antiviral therapy, owing to the possibility of late viral relapse and tumorigenesis.

4-Bromo-1,8-naphthalimide derivatives as fluorogenic substrates for live cell imaging of glutathione S-transferase (GST) activity.

Fluorogenic substrates are used to visualize the activity of cancer-associated enzymes and to interpret biological events. Certain types of glutathione S-transferase (GST), such as Pi class GST (referred to as GSTP1), are more highly expressed in a wide variety of human cancer tissues compared to their corresponding normal tissues. Pi class GST is thus a cancer cell molecular marker and potential target for overcoming resistance to chemotherapy. Here, we report that 4-bromo-1,8-naphthalimide (BrNaph) is a practical fluorogenic GST substrate. We have found that HE-BrNaph, an N-hydroxyethyl derivative, shows remarkable fluorescence enhancement upon GST-catalyzed SNAr replacement of the bromo group with a glutathionyl group. This substitution was highly selective and occurred only in the presence of GSH/GSTs; no non-enzymatic reaction was observed. We demonstrated that HE-BrNaph allows visualization of GST activity in living cells and enables to distinguish cancer cells from normal cells. Further, various N-substitutions in BrNaph retain susceptibility to enzymatic activity and isozyme selectivity, suggesting the applicability of BrNaph derivatives. Thus, BrNaph and its derivatives are GST substrates useful for fluorescence imaging and the intracellular detection of GSTP1 activity in living cells.

A highly selective fluorogenic substrate for imaging glutathione S-transferase P1: development and cellular applicability in epigenetic studies.

Pi-class glutathione S-transferase (GSTP1) is a molecular marker enzyme whose expression level is altered in various malignant tumour tissues. Herein, we report the first highly selective fluorogenic GSTP1 substrate, Ps-TG, and its membrane-permeable derivative Ps-TAc, for specific visualization of intracellular GSTP1 activity in cancer cells or epigenetically regulated GSTP1 expression.

A case of adenomyoepithelioma with myoepithelial carcinoma of the breast.

Adenomyoepithelioma with myoepithelial carcinoma of the breast is rare and diagnosed with histology and immunohistochemistry. We present a case of malignant transformation over 10 years, with ultrasonographic findings, highlighting the importance of an early excisional biopsy. Conservative surgery and radiation therapy were performed. There was no recurrence for 2 years.

The hepatic capsular arteries: imaging features and clinical significance.

BACKGROUND: Although the anatomical features of the hepatic capsular arteries have been previously reported, the radiological and clinical importance of these arteries has not been well documented. IMAGING FINDINGS: We injected barium sulfate into the intra- and extra-hepatic arteries in cadavers to investigate the hepatic capsular arteries. The web-like hepatic capsular arteries derived from the capsular branch of the peripheral hepatic arteries are called isolated arteries. There were anastomoses between the intra- and extra-hepatic arteries (inferior phrenic artery, superior falciform ligament artery, and cystic artery) through the hepatic capsular arteries. CLINICAL SIGNIFICANCE: We reviewed the radiology database and assessed clinical cases. When the hepatic artery is occluded, the collateral vessels, such as the inferior phrenic artery and the superior falciform ligament artery, develop via the hepatic capsular arteries at the right triangular ligament and falciform ligament, respectively. Bleeding from capsular arteries causes extensions of the subcapsular hematoma. CONCLUSION: The hepatic capsular arteries spread along the hepatic surface and constitute the vascular network throughout the liver. These arteries play an important role in collateral circulation in various clinical situations, as well as subcapsular hematoma.

Nivolumab-induced myocardial necrosis in a patient with lung cancer: A case report.

A 74-year-old man with lung adenocarcinoma recurrence was admitted to our hospital because of dyspnea 7 days after receiving initial immunotherapy with nivolumab. Electrocardiography revealed ST-segment elevation in V1-6 and echocardiography showed a markedly reduced left ventricular ejection fraction of 9% and akinesis of the anteroseptal wall and apex. He died from acute heart failure 3 days after admission. Microscopically, multiple small foci of myocardial necrosis with few inflammatory cells were scattered in both ventricles. Obstruction of the coronary artery was not identified. We believed that the cause of death was acute heart failure possibly due to nivolumab-induced myocardial necrosis.

Rapidly progressive miliary brain metastasis of lung cancer after EGFR tyrosine kinase inhibitor discontinuation: An autopsy report.

Miliary brain metastasis is a rare type of brain metastasis, in which carcinoma cells disseminate to numerous foci confined to Virchow-Robin/subpial spaces. Symptoms usually progress within several months, and magnetic resonance imaging (MRI) shows multiple small contrast-enhancing lesions. We report an autopsy case of a patient who rapidly deteriorated within a week due to miliary brain metastasis after epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) discontinuation, without contrast-enhancing lesions on MRI. A 74-year-old woman was diagnosed with stage IV lung adenocarcinoma with EGFR L868R mutation 2 years before presentation. Gefitinib, an EGFR-TKI was started. After 7 months, multiple new punctate contrast-enhancing lesions in the cerebral cortex appeared. After switching to another EGFR-TKI, erlotinib, these lesions disappeared. One year later, erlotinib was discontinued because of disease progression in the lung and docetaxel was initiated. Sixteen days later, cognitive decline appeared which rapidly progressed to bedridden state in 4 days. MRI showed multiple cortical small fluid-attenuated inversion recovery high intensity lesions which lacked contrast enhancement. The patient exhibited a state of akinetic mutism within a few days, and died 52 days after the appearance of neurological symptoms. The rapid progression indicated disease flare after EGFR-TKI discontinuation. Autopsy revealed numerous foci of metastasis in the cerebral cortex, basal ganglia, thalamus, and cerebellum, in which cancer cells were mostly confined to the Virchow-Robin/subpial spaces. These pathological findings were compatible with previous reports of miliary brain metastasis. Recent reports suggest that early disseminated cancer cells can survive for a long time and even remain after chemotherapy in supportive niches, and Virchow-Robin spaces are the niches in the brain. Our case suggests that these cancer cells may rapidly proliferate as a withdrawal burst after discontinuation of molecular targeted drugs, and show pathological findings of miliary brain metastasis.

Granulomatosis with Polyangiitis Localized in the Greater Omentum.

Granulomatosis with polyangiitis (GPA) is known as anti-neutrophil cytoplasmic antibody- (ANCA-) associated small vessel vasculitis and typically manifests as pulmonary-renal syndrome, but the disease is not limited to pulmonary or renal systems. The inflammation can involve whole body organs. In addition, the ANCA titer does not always become positive. Here, we describe the case of a 91-year-old man who presented with umbilical pain and fever of unknown origin. Only the increased computed tomography value of the greater omentum suggested intra-abdominal inflammation; however, serological examinations, including the ANCA level, could not reveal the focus or cause of symptoms. Finally, the histopathological examination of specimens surgically excised from the greater omentum demonstrated GPA limited to the greater omentum. This report reminds physicians to consider GPA in the differential diagnosis of acute abdominal pain or fever of unknown origin.

Pancreaticoduodenectomy for an Ampullary Region Carcinoma Occurred in Annular Pancreas Coexistent with Replaced Common Hepatic Artery.

INTRODUCTION: Annular pancreas is a rare congenital abnormality characterized by a ring of pancreatic tissue surrounding the descending portion of the duodenum. Annular pancreas coexisting with replaced common hepatic artery which is also a rare anatomical variation has not been reported previously. CASE PRESENTATION: A 53-year-old man visited our hospital complaining of epigastric pain. Based on radiological examinations, he was diagnosed as having pancreatitis, annular pancreas, and hepatomesenteric trunk. One month later, obstructive jaundice developed. Endoscopic examination revealed ampullary region carcinoma. We performed pancreaticoduodenectomy using the "artery-first" approach. DISCUSSION: Both annular pancreas and common hepatic artery anomaly are rare. High-quality preoperative imaging and awareness of such rare conditions are necessary for operative safety. Although the embryological relationship between these anomalies is uncertain, the present case may suggest some relevance between the two. CONCLUSION: The "artery-first" approach may be a useful method for pancreaticoduodenectomy in patients who have an anatomical abnormality.

Pulmonary Tumor Thrombotic Microangiopathy due to Advanced Gastric Cancer with Virchow's Node Metastasis.

Pulmonary tumor thrombotic microangiopathy (PTTM) is a fatal cancer-related complication characterized by severe progressive pulmonary hypertension. Antemortem diagnosis is difficult owing to the rapid progression of the condition, especially when the patient has no known malignancies and initially presents with pulmonary hypertension. Here we report a case of PTTM due to occult gastric cancer with metastasis in the left supraclavicular lymph node, also known as Virchow's node. Enlarged Virchow's node is an important indicator of advanced gastric cancer. In patients with progressive pulmonary hypertension of unknown origin, enlarged Virchow's node can be an important indicator for the diagnosis of PTTM.

Fluorescein diacetate (FDA) and its analogue as substrates for Pi-class glutathione S-transferase (GSTP1) and their biological application.

Pi class glutathione S-transferase (GSTP1) is highly expressed in various cancerous cells and pre-neoplastic legions, where it is involved in apoptotic resistance or metabolism of several anti-tumour chemotherapeutics. Therefore, GSTP1 is a marker of malignant and pre-malignant cells and is a promising target for visualization and drug development. Here we demonstrate that fluorescein diacetate (FDA), a fluorescent probe used for vital staining, is a fluorescently activated by esterolytic activity of human GSTP1 (hGSTP1) selectively among various cytosolic GSTs. Fluorescence activation of FDA susceptible to GST inhibitors was observed in MCF7 cells exogenously overexpressing hGSTP1, but not in cells overexpressing hGSTA1 or hGSTM1. Inhibitor-sensitive fluorescence activation was also observed in several cancer cell lines endogenously expressing GSTP1, suggesting that GSTP1 is involved in FDA esterolysis in these cells. Among the FDA derivatives examined, FOMe-Ac, the acetyl ester of fluorescein O-methyl ether, was found to be a potential reporter for GSH-dependent GSTP1 activity as well as for carboxylesterase activity. Since GSTP1 is highly expressed in various types of cancer cells compared to their normal counterparts, improving the fluorogenic substrates to be more selective to the esterolysis activity of GSTP1 rather than carboxylesterases should lead to development of tools for detecting GSTP1-overexpressing cancer cells and investigating the biological functions of GSTP1.

A case of herpes simplex virus pneumonia detected by sputum cytodiagnosis.

A sputum test is noninvasive and simple. It contributed to correct diagnosis of a patient with severe acute respiratory failure. We again point out the usefulness of sputum cytodiagnosis for differentiating severe pneumonia.

The protective role of YAP1 on ER stress-induced cell death in vascular smooth muscle cells.

Apoptosis of vascular smooth muscle cells (VSMCs) has been implicated in the progression of atherosclerosis, especially in vascular remodelling and plaque rupture. Although it is known that Yes-associated protein 1 (YAP1) is a critical molecule that regulates cell proliferation, differentiation and apoptosis, the role of YAP1 in VSMCs apoptosis remains unknown. In this study, we investigated whether YAP1 modulates VSMC apoptosis induced by endoplasmic reticulum (ER) stress. In cultured VSMC, tunicamycin caused cell death accompanied by an increase in caspase-3 processing and C/EBP homologous protein (CHOP) expression. YAP1 protein expression was downregulated by tunicamycin and the phosphorylation of YAP1 at the Ser127 site was significantly increased by tunicamycin. Tunicamycin further decreased cell viability followed by an increase in caspase-3 processing in the absence of YAP1 when compared with treatment only with tunicamycin or siYAP1. On the other hand, overexpression of a constitutively active YAP1 (YAP1-5SA), which lacks five serine phosphorylation sites, significantly prevented the caspase-3 processing and restored the decrease in cell viability induced by tunicamycin. Overexpression of YAP1-5SA significantly inhibited tunicamycin-induced caspase-8 processing without affecting phosphorylation of p-38 and Akt. Furthermore, the overexpression of YAP1-5SA significantly restored the decrease in ANKRD1 expression induced by tunicamycin. The inhibition of tunicamycin-induced caspase-3 cleavage by YAP1-5SA was markedly attenuated in ANKRD1-knockdown cells. These results demonstrate that ER stress can alter intracellular YAP1 protein expression in VSMCs and that YAP1 is protective against VSMC apoptosis induced by ER stress through inhibiting caspase8/3 activation mediated in part by upregulation of ANKRD1.

[A Surgical Case of Intrapulmonary Bronchogenic Cyst Treated by Left Lower Lobectomy for Hemopneumothorax and Repeated Hemoptysis].

A 79-year-old female visited a hospital because of high fever and computed tomography(CT)showed a cystic lesion with fluid accumulation in her left lung. She had hemoptysis and left chest pain 3 days after antibiotic therapy was started. Chest CT demonstrated the cystic lesion rupturing and causing hemopneumothorax. Then she was referred to our department and thoracic drainage was performed. However, a week after the drainage, she had hemoptysis and chest pain again, and the left lower lobectomy was performed. Histopathological findings showed the cystic lesion was intrapulmonary bronchogenic cyst. We describe a rare case of the hemopneumothorax due to the hemorrhage in the bronchogenic cyst.

Dialysis Amyloid Deposition in the Aortic Valve and Its Association with Aortic Stenosis.

BACKGROUND: The relationship between dialysis amyloid (DA) deposition in the aortic valve (AV) and aortic stenosis (AS) is unknown. METHODS: This was a cross-sectional study. AV specimens of dialysis patients (median vintage: 8.8 years) consecutively collected from cardiac surgeries (n = 56) or autopsies (n = 13) were examined by a board-certified pathologist blinded to clinical data. DAs were considered to be present if deposits were stained both by Congo red with apple-green birefringence under polarized light and by anti-ß2-microblobulin antibody. Degree of deposition was graded as follows: Amyloid (-), no deposit; Amyloid (1+), occasional small deposits; Amyloid (2+), multiple small to large deposits or a single large deposit. Calcification was defined as a calcified deposit with a diameter >1 mm in the specimen. Severe AS (sAS) was defined as a mean gradient >50 mm Hg by echocardiogram. We examined the proportion of DAs and the association between DAs and the sAS. RESULTS: DAs were present in 71% (n = 49) of specimens and primarily co-localized with calcification. Non-dialysis related amyloid was found in one specimen. After excluding this specimen, sAS was associated with 'Amyloid (1+) and Calcification >1 mm' and 'Amyloid (2+) and Calcification >1 mm' (vs. 'Amyloid (-) and Calcification ≤1 mm', odds ratios (ORs): 13.5 and 34.2, respectively). Furthermore, after adjustment for covariates, sAS was found to be associated with 'Amyloid (2+) and Calcification >1 mm' (OR: 24.3). CONCLUSIONS: DA deposition in the AV was prevalent among dialysis patients. DA deposition with accompanying calcification might contribute to the severity of AS.

Complete Surgical Resection of a Leiomyosarcoma Arising from the Inferior Vena Cava.

A 76-year-old Japanese man was referred to our hospital with chief complaint of right hypochondoralgia. Abdominal ultrasound showed a retroperitoneal tumor in the suprarenal region of the right kidney. Computed tomography revealed an enhanced lobular tumor with irregular, circumscribed, and indistinct border. Ultrasound-guided biopsy was performed. The tumor consisted of spindle-shaped cells with a giant nucleus and multinuclear cells. The diagnosis was leiomyosarcoma by immunohistochemical staining. The patient underwent surgery accessed by a right eighth intercostal thoracoabdominal incision. The tumor was completely resected, accompanied by removal of the posterosuperior segment of the right hepatic lobe, right adrenal gland, and a portion of the inferior vena cava (IVC). The histopathologic diagnosis was leiomyosarcoma arising from the IVC. We present a rare case of a successfully managed leiomyosarcoma of the IVC. This case suggests the importance of curative surgical resection of the tumor due to low efficacy of adjuvant chemotherapy for leiomyosarcoma.