Epstein-Barr Virus BRLF1 Induces PD-L1 Expression in Nasopharyngeal Carcinoma Cells.

Nasopharyngeal carcinoma (NPC) is a specific human malignancy with unique geographic distribution and genetic backgrounds. Although early treatment with radio-chemotherapy has been proven effective for NPC therapy, its therapeutic efficacy substantially diminishes in the late stages of this malignancy. In the tumor microenvironment of NPC, PD-L1 has been demonstrated as a critical factor in impairing T cell activation. As an etiological role for NPC development, it is found that Epstein-Barr virus (EBV) latent proteins upregulated PD-L1 expression. However, whether EBV lytic protein affects PD-L1 expression remains unclear. In this study, through monitoring the mRNA expression pattern of lytic genes and PD-L1 in EBV-positive NPC cell line NA, EBV immediately-early gene BRLF1(Rta) was found to have the potential for PD-L1 activation. Furthermore, we identified that Rta expression enhanced PD-L1 expression in mRNA and protein levels through quantitative real-time polymerase chain reaction and western blotting analysis. The luciferase reporter assay revealed that Rta expression enhanced PD-L1 promoter activity. We also demonstrated that Rta-induced PD-L1 expressions could impair interleukin 2 secretion of T cells, and this mechanism may be through ERK activation. These results displayed the importance of EBV Rta in PD-L1 expression in NPC and may give an alternative target for NPC therapy.

Screening and identification of emodin as an EBV DNase inhibitor to prevent its biological functions.

BACKGROUND: The Epstein-Barr virus (EBV) is a prevalent oncovirus associated with a variety of human illnesses. BGLF5, an EBV DNase with alkaline nuclease (AN) activity, plays important roles in the viral life cycle and progression of human malignancies and has been suggested as a possible diagnostic marker and target for cancer therapy. Methods used conventionally for the detection of AN activity, radioactivity-based nuclease activity assay and DNA digestion detection by gel electrophoresis, are not suitable for screening AN inhibitors; the former approach is unsafe, and the latter is complicated. In the present study, a fluorescence-based nuclease activity assay was used to screen several natural compounds and identify an EBV DNase inhibitor. RESULTS: Fluorescence-based nuclease activity assays, in which the DNA substrate is labelled with PicoGreen dye, are cheaper, safer, and easier to perform. Herein, the results of the fluorescence-based nuclease activity assay were consistent with the results of the two conventional methods. In addition, the PicoGreen-labelling method was applied for the biochemical characterisation of viral nucleases. Using this approach, we explored EBV DNase inhibitors. After several rounds of screening, emodin, an anthraquinone derivative, was found to possess significant anti-EBV DNase activity. We verified the efficacy of emodin using the conventional DNA-cleavage assay. Furthermore, using comet assay and micronucleus formation detection, we confirmed that emodin can inhibit DNase-induced DNA damage and genomic instability. Additionally, emodin treatment inhibited EBV production. CONCLUSIONS: Using a PicoGreen-mediated nuclease activity assay, we successfully demonstrated that emodin has the potential to inhibit EBV DNase nuclease activity. Emodin also inhibits EBV DNase-related biological functions, suggesting that it is a potential inhibitor of EBV DNase.

The Dietary Flavonol Kaempferol Inhibits Epstein-Barr Virus Reactivation in Nasopharyngeal Carcinoma Cells.

Kaempferol (KP, 3,4',5,7-tetrahydroxyflavone), a dietary flavonol, has anti-cancer, antioxidant, anti-inflammatory, antimicrobial, and antimutagenic functions. However, it is unknown whether kaempferol possesses anti-Epstein-Barr virus (EBV) activity. Previously, we demonstrated that inhibition of EBV reactivation represses nasopharyngeal carcinoma (NPC) tumourigenesis, suggesting the importance of identifying EBV inhibitors. In this study, Western blotting, immunofluorescence staining, and virion detection showed that kaempferol repressed EBV lytic gene protein expression and subsequent virion production. Specifically, kaempferol was found to inhibit the promoter activities of Zta and Rta (Zp and Rp) under various conditions. A survey of the mutated Zp constructs revealed that Sp1 binding regions are critical for kaempferol inhibition. Kaempferol treatment repressed Sp1 expression and decreased the activity of the Sp1 promoter, suggesting that Sp1 expression was inhibited. In conclusion, kaempferol efficiently inhibits EBV reactivation and provides a novel choice for anti-EBV therapy and cancer prevention.

A Balance between Transmembrane-Mediated ER/Golgi Retention and Forward Trafficking Signals in Glycophorin-Anion Exchanger-1 Interaction.

Anion exchanger-1 (AE1) is the main erythroid Cl-/HCO3- transporter that supports CO2 transport. Glycophorin A (GPA), a component of the AE1 complexes, facilitates AE1 expression and anion transport, but Glycophorin B (GPB) does not. Here, we dissected the structural components of GPA/GPB involved in glycophorin-AE1 trafficking by comparing them with three GPB variants-GPBhead (lacking the transmembrane domain [TMD]), GPBtail (mainly the TMD), and GP.Mur (glycophorin B-A-B hybrid). GPB-derived GP.Mur bears an O-glycopeptide that encompasses the R18 epitope, which is present in GPA but not GPB. By flow cytometry, AE1 expression in the control erythrocytes increased with the GPA-R18 expression; GYP.Mur+/+ erythrocytes bearing both GP.Mur and GPA expressed more R18 epitopes and more AE1 proteins. In contrast, heterologously expressed GPBtail and GPB were predominantly localized in the Golgi apparatus of HEK-293 cells, whereas GBhead was diffuse throughout the cytosol, suggesting that glycophorin transmembrane encoded an ER/Golgi retention signal. AE1 coexpression could reduce the ER/Golgi retention of GPB, but not of GPBtail or GPBhead. Thus, there are forward-trafficking and transmembrane-driven ER/Golgi retention signals encoded in the glycophorin sequences. How the balance between these opposite trafficking signals could affect glycophorin sorting into AE1 complexes and influence erythroid anion transport remains to be explored.

Composition, Morphology, and Interface Engineering of 3D Cauliflower-Like Porous Carbon-Wrapped Metal Chalcogenides as Advanced Electrocatalysts for Quantum Dot-Sensitized Solar Cells.

Designing a low-cost, highly efficient, and stable electrocatalyst that can synergistically speed up the reduction of polysulfide electrolytes while operative for long periods in the open air is critical for the practical application of quantum dot-sensitized solar cells (QDSSCs), but it remains a challenging task. Herein, a simple, straightforward, and two-step nanocomposite engineering approach that simultaneously combines metallic copper chalcogenides (MC) either Cu2- x S or Cu2- x Se with S, N dual-doped carbon (SNC) sources for devising high-quality counter electrode (CE) film are reported. First, the hierarchically assembled MC nanostructures are obtained using microwave-assisted synthesis. Second, these MCs are embedded within an ordered macro-meso-microporous carbon matrix to obtain Cu2- x S@C or Cu2- x SeS@C CE. These CEs are demonstrated to have composition dependents crystal structure, surface morphologies, photovoltaic performance, and electrochemical properties. In terms of power conversion efficiency (PCE), the Cu2- x SeS@C (9.89%) and Cu2- x S@C-CE (8.96%) constructed QDSSCs outperform both Cu2- x Se (8.96%) and Cu2- x S-constructed (7.79%) QDSSCs, respectively. The enhanced PCE could be attributed to the synergistic interaction of S and N dopants with MC interfaces that can not only enrich electric conductivity, and a higher surface-to-volume ratio but also offers a 3D network for superior charge transport at the interface.

Prophylactic hyperthermic intraperitoneal chemotherapy for patients with clinical T4 gastric cancer.

INTRODUCTION: Patients with clinical T4 gastric cancers have high recurrence rates and low 5-year overall survival (OS) despite radical gastrectomy with D2 lymphadenectomy and adjuvant chemotherapy. The invisible peritoneal metastasis may result in local recurrence due to the tumor invading the serosa and nearby organs. Prophylactic hyperthermic intraperitoneal chemotherapy (HIPEC) has been suggested as an adjuvant treatment strategy in these patients. We evaluated the efficacy of prophylactic HIPEC post-gastrectomy for patients with clinical T4 gastric cancer. MATERIALS AND METHODS: We retrospectively reviewed data from 132 patients with clinical T4 gastric cancer who underwent gastrectomy + D2 lymphadenectomy between 2014 and 2020. Thirty-five of these patients also underwent prophylactic HIPEC perioperatively. We used propensity score matching (PSM) to reduce selection bias. We evaluated the risk factors for recurrence and compared the OS and disease-free survival (DFS) between the gastrectomy and prophylactic HIPEC groups. RESULTS: A total of 132 eligible patients were included in the study. Seventy preoperative patient characteristics were homogeneous post-PSM. Prophylactic HIPEC seemed to reduce the risk of postoperative peritoneal recurrence but did not influence the risk of distant metastasis. The risk factors for recurrence included advanced N stage, ascites, and lymphovascular invasion. OS (adjusted hazard ratio, 0.37; 95% CI, 0.17 to 0.81; p = 0.035) and DFS (adjusted hazard ratio, 0.33; 95% CI, 0.15 to 0.72; p = 0.017) were better in the prophylactic HIPEC group than in the gastrectomy alone group. CONCLUSIONS: Prophylactic HIPEC plus radical gastrectomy can reduce peritoneal recurrence and improve OS and DFS in patients with clinical T4 gastric cancer.

Conversion Surgery for Patients with Advanced Gastric Cancer with Peritoneal Carcinomatosis.

BACKGROUND: Patients with advanced gastric cancer (AGC) with peritoneal carcinomatosis (PC) usually have poor outcomes and high mortality risk, even with cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC). This study analyzed the prognostic factors of AGC with PC and evaluated laparoscopic HIPEC (LHIPEC) plus neoadjuvant intraperitoneal and systemic chemotherapy (NIPS) as a conversion surgery for AGC patients with PC with a poor initial prognosis. Patient and Methods. We retrospectively evaluated 127 patients with AGC and PC from January 1, 2012, to March 1, 2020. After the exclusion of 32 ineligible patients, the conversion group comprised 34 patients who underwent LHIPEC + NIPS as a conversion surgery followed by CRS plus HIPEC. The CRS + HIPEC group included 15 patients who underwent CRS with HIPEC alone. Additionally, the C/T group comprised 23 patients who received systemic chemotherapy, and the palliative group comprised 23 patients who received only conservative therapy or palliative gastrectomy. RESULTS: The conversion group demonstrated a significantly better mean overall survival compared to the CRS + HIPEC, C/T, and palliative groups (p < 0.001). Patients in the conversion group who underwent LHIPEC + NIPS had significantly decreased peritoneal cancer index (PCI) scores (p < 0.001) and ascites (p=0.003). Malignant ascites amount also significantly decreased after treatment in the LHIPEC + NIPS group (p < 0.001). CONCLUSIONS: LHIPEC + NIPS can significantly improve the overall survival, the PCI score, and malignant ascites amount in peritoneal cytology-positive gastric cancer with PC, and an initially high PCI score. Therefore, it may be a feasible conversion strategy for AGC patients with PC.

Somatostatin Therapy in Patients with Massive Ascites After Liver Transplantation.

BACKGROUND Patients with massive ascites (MA) after liver transplantation (LT, defined here as daily ascitic drainage more than 1000 ml per day for more than 7 days after liver transplantation) are at increased risks of infection, hypoalbuminemia, graft loss, and even mortality. The aim of this retrospective cohort study was to investigate the effects of somatostatin on patients with MA after LT. MATERIAL AND METHODS Twenty-eight patients with liver cirrhosis or hepatocellular carcinoma who underwent LT complicated by MA postoperatively were included. Ten participants were receiving somatostatin therapy. The postoperative course and adverse drug effects were investigated. Daily postoperative ascitic drainage and urine output were also recorded and compared to those in the non-somatostatin group. RESULTS The somatostatin group had significantly less ascites drainage after LT compared to the non-somatostatin group (p=0.002). Urine output was significantly increased after somatostatin administration (p<0.001). No serious adverse effects influencing graft function or fatal complications occurred after somatostatin therapy. CONCLUSIONS Somatostatin treatment is beneficial for the management of MA after liver transplantation.

Ovarian metastases from gallbladder mimics primary ovarian neoplasm in young patient: a case report.

BACKGROUND: Gallbladder cancer is unusually seen but can result in highly mortality rate. It makes challenge to diagnose for clinicians due to present asymptomatic or non-specific clinical presentation including abdominal pain, anorexia. It usually also accompanies with cholelithiasis (incidence is 1-2%) and incidentally detected by radiologic examination such as ultrasound, computed tomography or intra-operative intervention accidentally. Gallbladder cancer results in highly fatal malignancy because it is difficult to early detect. The ovarian metastases from gallbladder mimics primary neoplasm isn't seen before and mentioned in English literatures before. CASE PRESENTATION: A 28-year-old woman suffered from intermittently lower abdominal tenderness and nausea after meals for 3 years. The abdominal ultrasound revealed a right ovarian mass with fluid accumulation and the contrast CT of abdomen revealed a gallbladder fundus mass and liver tumor lesion located at segment 4. We arranged surgical intervention with radical cholecystectomy and debulking operation with salpingo-oophorectomy. The pathologic report revealed adenocarcinoma of gallbladder with liver, peritoneum, and right ovarian invasion. After surgical intervention, she also received adjuvant chemotherapy with Gemcitabine, Cetuximab, Cisplatin and Cyberknife. CONCLUSION: The non-specific symptoms make the challenge to difference the primary malignant neoplasm. The rarely diagnosis must take in consider if the gastrointestinal tract tumours coexist with ovarian tumours.

Adaptable interaction between aquaporin-1 and band 3 reveals a potential role of water channel in blood CO2 transport.

Human CO2 respiration requires rapid conversion between CO2 and HCO3- Carbonic anhydrase II facilitates this reversible reaction inside red blood cells, and band 3 [anion exchanger 1 (AE1)] provides a passage for HCO3- flux across the cell membrane. These 2 proteins are core components of the CO2 transport metabolon. Intracellular H2O is necessary for CO2/HCO3- conversion. However, abundantly expressed aquaporin 1 (AQP1) in erythrocytes is thought not to be part of band 3 complexes or the CO2 transport metabolon. To solve this conundrum, we used Förster resonance energy transfer (FRET) measured by fluorescence lifetime imaging (FLIM-FRET) and identified interaction between aquaporin-1 and band 3 at a distance of 8 nm, within the range of dipole-dipole interaction. Notably, their interaction was adaptable to membrane tonicity changes. This suggests that the function of AQP1 in tonicity response could be coupled or correlated to its function in band 3-mediated CO2/HCO3- exchange. By demonstrating AQP1 as a mobile component of the CO2 transport metabolon, our results uncover a potential role of water channel in blood CO2 transport and respiration.-Hsu, K., Lee, T.-Y., Periasamy, A., Kao, F.-J., Li, L.-T., Lin, C.-Y., Lin, H.-J., Lin, M. Adaptable interaction between aquaporin-1 and band 3 reveals a potential role of water channel in blood CO2 transport.

The role of liver transplantation or resection for patients with early hepatocellular carcinoma.

Liver resection (LR) and liver transplantation (LT) are curative treatments for early hepatocellular carcinoma (HCC), although their performance remains debated. We compared the survival of patients with HCC conforming to the Milan criteria (MC) after LT and LR and analyzed factors affecting clinical outcomes. Between January 2006 and January 2013, 65 and 184 patients received LT and LR for HCCs fulfilling the MC, respectively. Overall survival (OS) and disease-free survival (DFS) rates were compared between the two groups. To investigate effects of liver function and living donor liver transplantation (LDLT) on survival, two subgroup analyses were performed and associations with OS and DFS were examined. We found that OS rates were higher after LT than after LR since 3 years postoperatively. DFS rates were significantly better after LT than after LR. Performance of LR, vascular invasion, and tumor multiplicity were associated with poor DFS, and factors affecting OS included the presence of vascular invasions, liver cirrhosis, and tumor multiplicity. In conclusion, despite of the effects of tumor characteristics on clinical outcomes, LT, including LDLT, should be considered the treatment of choice for patients with HCCs who met the MC. The role of LR is to identify poor prognostic factors through pathological examination.

Expedited CO2 respiration in people with Miltenberger erythrocyte phenotype GP.Mur.

In Southeast Asia, Miltenberger antigen subtype III (Mi.III; GP.Mur) is considered one of the most important red blood cell antigens in the field of transfusion medicine. Mi.III functions to promote erythrocyte band 3 expression and band 3-related HCO3(-) transport, with implications in blood CO2 metabolism. Could Mi.III affect physiologic CO2 respiration in its carriers? Here, we conducted a human trial to study the impacts of Mi.III expression in respiration. We recruited 188 healthy, adult subjects for blood typing, band 3 measurements, and respiratory tests before and after exercise. The 3-minute step exercise test forced the demand for CO2 dissipation to rise. We found that immediately following exercise, Mi.III + subjects exhaled CO2 at greater rates than Miltenberger-negative subjects. Respiration rates were also higher for Mi.III + subjects immediately after exercise. Blood gas tests further revealed distinct blood CO2 responses post-exercise between Mi.III and non-Mi.III. In contrast, from measurements of heart rates, blood O2 saturation and lactate, Mi.III phenotype was found to be independent of one's aerobic and anaerobic capacities. Thus, Mi.III expression supported physiologic CO2 respiration. Conceivably, Mi.III + people may have advantages in performing physically enduring activities.

Emergency endovascular aortic repair of a ruptured mycotic aorto-iliac aneurysm presenting with lumbar radiculopathy.

Ruptured abdominal aortic aneurysm is life-threatening without immediate management. The initial clinical presentation is non-specific and impending rupture is easily missed, especially without a CT scan. We present a case of a 56-year-old man with low-back pain and left lower-extremity numbness, which was diagnosed as a herniated intervertebral disc (HIVD) with left acute sciatica syndrome. He also complained of persistent fever and abdominal discomfort. Routine blood work-up revealed leukocytosis and decreasing haemoglobin levels. CT angiography (CTA) showed impending rupture of the left aorto-iliac aneurysm. We therefore performed endovascular aneurysm repair (EVAR). Blood culture revealed Salmonella enterica, for which he received antibiotics. No acute sciatica syndrome was present immediately after the EVAR. No EVAR-related complications were noted in the one-year CTA follow up.

A direct blood polymerase chain reaction approach for the determination of GP.Mur (Mi.III) and other Hil+ Miltenberger glycophorin variants.

BACKGROUND: GP.Mur (Mi.III) is a glycophorin B-A-B hybrid sialoglycoprotein expressing several potent immunogens, including Mi(a), Mur, and Hil. GP.Mur is considered one of the most important red blood cell (RBC) phenotypes in blood banking in Southeast Asia. However, there are no antibodies commercially available for the screening of GP.Mur RBCs. STUDY DESIGN AND METHODS: To develop a direct blood polymerase chain reaction (PCR) approach for the screening of GP.Mur cells, we first confirmed the genomic sequence differences among four GP.Mur and three Mi(a-) samples by sequencing their GYP.Mur and GYPB genes. With these data, we designed PCR primers that best discriminate GYPB and GYP.Mur. Our primer design also allows the detection of other Hil+ glycophorin variants. We also constructed two plasmids--pGBi2i3 and pMiIIIi2i3--which serve as the negative and positive control DNA, respectively, for the PCR procedure. Additionally, we designed a control PCR to be run side by side with the typing PCR. RESULTS: Because of the high specificity of our primers, we found it unnecessary to extract DNA from blood samples for PCR. We have tested this PCR method on 379 fresh and frozen blood samples. The results were further validated by serology and DNA sequencing and were shown to be completely accurate in our hand. We also found that the rapid genotyping method--high-resolution melting--can be a timesaving alternative for DNA sequencing. CONCLUSION: This direct blood PCR approach for determination of GP.Mur and related Hil+ phenotypes is reliable and economical and is expected to be useful for blood banking in Southeast Asia.

Background K(2P) channels KCNK3/9/15 limit the budding of cell membrane-derived vesicles.

The main function of background two-pore potassium (K(2P)) channels KCNK3/9/15 is to stabilize the cell membrane potential. We previously observed that membrane potential depolarization enhances the release of HIV-1 viruses. Because membrane polarization affects the biomembrane directly, here we examined the effects of KCNK3/9/15 on the budding of nonviral vesicles. We found that depolarization by knocking down endogenous KCNK3/9/15 promoted secretion of cell-derived vesicles. We further used Vpu (an antagonist of KCNK3) as a model for the in vivo study of depolarization-stimulated secretion. Vpu is a HIV-1-encoded, ion channel-like protein (viroporin) capable of enhancing virus release and depolarizing the cell membrane potential. We found that Vpu could also promote nonviral vesicle release, perhaps through a similar mechanism that Vpu utilizes to promote viral particle release. Notably, T cells expressing Vpu alone became pathologically low in intracellular K(+) and insensitive to extracellular K(+) or membrane potential stimulation. In contrast, heterologous expression of KCNK3 in T cells stabilized the cell potentials by maintaining intracellular K(+). We thus concluded that KCNK3/9/15 expression limits membrane depolarization and depolarization-induced secretion at least in part by maintaining intracellular K(+).