Lowering the threshold of alanine aminotransferase for enhanced identification of significant hepatic injury in chronic hepatitis B patients.

BACKGROUND: The clinical and histological features of chronic hepatitis B (CHB) patients who fall into the "grey zone (GZ)" and do not fit into conventional natural phases are unclear. AIM: To explore the impact of varying the threshold of alanine aminotransferase (ALT) levels in identifying significant liver injury among GZ patients. METHODS: This retrospective analysis involved a cohort of 1617 adult patients diagnosed with CHB who underwent liver biopsy. The clinical phases of CHB patients were determined based on the European Association for the Study of the Liver 2017 Clinical Practice Guidelines. GZ CHB patients were classified into four groups: GZ-A (HBeAg positive, normal ALT levels, and HBV DNA ≤ 107 IU/mL), GZ-B (HBeAg positive, elevated ALT levels, and HBV DNA < 104 or > 107 IU/mL), GZ-C (HBeAg negative, normal ALT levels, and HBV DNA ≥ 2000 IU/mL), and GZ-D (HBeAg negative, elevated ALT levels, and HBV DNA ≤ 2000 IU/mL). Significant hepatic injury (SHI) was defined as the presence of notable liver inflammation (≥ G2) and/or significant fibrosis (≥ S2). RESULTS: The results showed that 50.22% of patients were classified as GZ, and 63.7% of GZ patients developed SHI. The study also found that lowering the ALT treatment thresholds to the American Association for the Study of Liver Diseases 2018 treatment criteria (35 U/L for men and 25 U/L for women) can more accurately identify patients with significant liver damage in the GZ phases. In total, the proportion of patients with ALT ≤ 40 U/L who required antiviral therapy was 64.86% [(221 + 294)/794]. When we lowered the ALT treatment threshold to the new criteria (30 U/L for men and 19 U/L for women), the same outcome was revealed, and the proportion of patients with ALT ≤ 40 U/L who required antiviral therapy was 75.44% [(401 + 198)/794]. Additionally, the proportion of SHI was 49.1% in patients under 30 years old and increased to 55.3% in patients over 30 years old (P = 0.136). CONCLUSION: These findings suggest the importance of redefining the natural phases of CHB and using new ALT treatment thresholds for better diagnosis and management of CHB patients in the GZ phases.

Targeting mitochondria-associated membranes as a potential therapy against endothelial injury induced by hypoxia.

Mitochondrial dysfunction plays a principal role in hypoxia-induced endothelial injury, which is involved in hypoxic pulmonary hypertension and ischemic cardiovascular diseases. Recent studies have identified mitochondria-associated membranes (MAMs) that modulate mitochondrial function under a variety of pathophysiological conditions such as high-fat diet-mediated insulin resistance, hypoxia reoxygenation-induced myocardial death, and hypoxia-evoked vascular smooth muscle cell proliferation. However, the role of MAMs in hypoxia-induced endothelial injury remains unclear. To explore this further, human umbilical vein endothelial cells and human pulmonary artery endothelial cells were exposed to hypoxia (1% O2 ) for 24 hours. An increase in MAM formation was uncovered by immunoblotting and immunofluorescence. Then, we performed small interfering RNA transfection targeted to MAM constitutive proteins and explored the biological effects. Knockdown of MAM constitutive proteins attenuated hypoxia-induced elevation of mitochondrial Ca2+ and repressed mitochondrial impairment, leading to an increase in mitochondrial membrane potential and ATP production and a decline in reactive oxygen species. Then, we found that MAM disruption mitigated cell apoptosis and promoted cell survival. Next, other protective effects, such as those pertaining to the repression of inflammatory response and the promotion of NO synthesis, were investigated. With the disruption of MAMs under hypoxia, inflammatory molecule expression was repressed, and the eNOS-NO pathway was enhanced. This study demonstrates that the disruption of MAMs might be of therapeutic value for treating endothelial injury under hypoxia, suggesting a novel strategy for preventing hypoxic pulmonary hypertension and ischemic injuries.

Nogo-B Receptor Directs Mitochondria-Associated Membranes to Regulate Vascular Smooth Muscle Cell Proliferation.

Mitochondria-associated membranes (MAM) are a well-recognized contact link between the mitochondria and endoplasmic reticulum that affects mitochondrial biology and vascular smooth muscle cells (VSMCs) proliferation via the regulation of mitochondrial Ca2+(Ca2+m) influx. Nogo-B receptor (NgBR) plays a vital role in proliferation, epithelial-mesenchymal transition, and chemoresistance of some tumors. Recent studies have revealed that downregulation of NgBR, which stimulates the proliferation of VSMCs, but the underlying mechanism remains unclear. Here, we investigated the role of NgBR in MAM and VSMC proliferation. We analyzed the expression of NgBR in pulmonary arteries using a rat model of hypoxic pulmonary hypertension (HPH), in which rats were subjected to normoxic recovery after hypoxia. VSMCs exposed to hypoxia and renormoxia were used to assess the alterations in NgBR expression in vitro. The effect of NgBR downregulation and overexpression on VSMC proliferation was explored. The results revealed that NgBR expression was negatively related with VSMCs proliferation. Then, MAM formation and the phosphorylation of inositol 1,4,5-trisphosphate receptor type 3 (IP3R3) was detected. We found that knockdown of NgBR resulted in MAM disruption and augmented the phosphorylation of IP3R3 through pAkt, accompanied by mitochondrial dysfunction including decreased Ca2+m, respiration and mitochondrial superoxide, increased mitochondrial membrane potential and HIF-1α nuclear localization, which were determined by confocal microscopy and Seahorse XF-96 analyzer. By contrast, NgBR overexpression attenuated IP3R3 phosphorylation and HIF-1α nuclear localization under hypoxia. These results reveal that dysregulation of NgBR promotes VSMC proliferation via MAM disruption and increased IP3R3 phosphorylation, which contribute to the decrease of Ca2+m and mitochondrial impairment.

Elevation of autophagy rescues spermatogenesis by inhibiting apoptosis of mouse spermatocytes.

Autophagy and apoptosis are interlocked in an extensive crosstalk. Our previous study demonstrated that hypotonic hypoxia-induced marked apoptosis of a spermatocyte-derived cell line (GC-2). However, whether hypoxia-induced apoptosis is mediated by inhibition of autophagy under hypoxic conditions remains unclear. In this study, GC-2 cells were cultured in 1% O2 and harvested at different time points. Autophagy was determined by acridine orange staining, cyto-ID staining, mCherry-GFP-LC3B adenovirus transfection and Western blotting for various autophagy markers. Apoptosis was detected by TUNEL staining, flow cytometry, JC-1 staining and Western blotting of apoptosis-related proteins. We found that hypoxia-induced apoptosis of GC-2 cells through mitochondrial and death receptor pathways and inhibited autophagic flux in GC-2 cells in a time-dependent manner. However, while marked autolysosome formation was observed in GC-2 cells before 24-h culture in hypoxic conditions, apparent apoptosis was observed only after 24-h culture in hypoxic conditions. Caspase-8 siRNA treatment induced cell survival, accompanied by induction of the mature autophagosome, acidic vesicular organelle formation and autophagic flux. Furthermore, Beclin-1 overexpression markedly attenuated the impairment of spermatogenesis in mice by inhibiting apoptosis of spermatocytes. The results of this study demonstrate that hypoxia inhibits autophagy, which further enhances hypoxia-induced apoptosis of mouse spermatocytes by promoting caspase-8 activation in a time-dependent manner, suggesting that combined application of apoptosis inhibition and autophagy activation might be a therapeutic strategy for treating hypoxia-induced male infertility.

Let­7d inhibits colorectal cancer cell proliferation through the CST1/p65 pathway.

Cystatin SN (cystatin 1, CST1) is a member of the cystatin superfamily which inhibits the proteolytic activity of cysteine proteases. CST1 is a tumor biomarker that provides useful information for the diagnosis of esophageal, gastric and colorectal carcinomas. MicroRNAs (miRNAs or miRs) play an important role in tumor cell proliferation. However, the exact role of let­7d and CST1 in colon cancer remains unknown. The aim of this study was to assess whether let­7d inhibits colorectal carcinogenesis through the CST1/p65 pathway, and determine whether it may be used as a potential target for clinical therapy. Microarray analysis of mRNAs extracted from colon cancer and normal tissues was performed. The results of gene expression microanalysis revealed that CST1 expression was upregulated in colon cancer compared with normal tissues. In addition, the upregulation of CST1 expression and the downregulation of let­7d expression in patients with colon cancer and in several colorectal cancer cell lines were confirmed by reverse transcription-quantitative PCR (RT­qPCR), immunohistochemistry and western blot analysis. In addition, siRNA targeting CST1 (CST1­siRNA) and let­7d-mimics were used in the HCT116 cells, and the results revealed that CST1 and let­7d played a role in colorectal cancer cell proliferation. Let­7d inhibited colorectal carcinogenesis through the CST1/p65 pathway. Thus, the findings of the present study indicate that CST1 may be a potential target for the future clinical therapy of colorectal cancer.

CLDN3 inhibits cancer aggressiveness via Wnt-EMT signaling and is a potential prognostic biomarker for hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) is one of the most common fatal malignancies but the molecular genetic basis of this disease remains unclear. By using genome-wide methylation profiling analysis, we identified CLDN3 as an epigenetically regulated gene in cancer. Here, we investigated its function and clinical relevance in human HCC. CLDN3 downregulation occurred in 87/114 (76.3%) of primary HCCs, where it was correlated significantly with shorter survival of HCC patients (P=0.021). Moreover, multivariate cyclooxygenase regression analysis showed that CLDN3 was an independent prognostic factor for overall survival (P=0.014). Absent expression of CLDN3 was also detected in 67% of HCC cell lines, which was significantly associated with its promoter hypermethylation. Ectopic expression of CLDN3 in HCC cells could inhibit cell motility, cell invasiveness, and tumor formation in nude mice. Mechanistic investigations suggested through downregulation of GSK3B, CTNNB1, SNAI2, and CDH2, CLDN3 could significantly suppress metastasis by inactivating the Wnt/ß-catenin-epithelial mesenchymal transition (EMT) axis in HCC cells. Collectively, our findings demonstrated that CLDN3 is an epigenetically silenced metastasis suppressor gene in HCC. A better understanding of the molecular mechanism of CLDN3 in inhibiting liver cancer cell metastasis may lead to a more effective management of HCC patients with the inactivation of CLDN3.

Primary duodenal NK/T-cell lymphoma with massive bleeding: A case report.

Primary natural killer/T-cell (NK/T-cell) lymphoma of the gastrointestinal tract is a very rare disease with a poor prognosis, and the duodenum is quite extraordinary as a primary lesion site. Here, we describe a unique case of a primary duodenal NK/T-cell lymphoma in a 26-year-old man who presented with abdominal pain and weight loss. Abdominal computed tomography scan demonstrated a hypodense tumor in the duodenum. Because of massive upper gastrointestinal tract bleeding during hospitalization, the patient was examined by emergency upper gastrointestinal endoscopy. Under endoscopy, an irregular ulcer with mucosal edema, destruction, necrosis, a hyperplastic nodule and active bleeding was observed on the duodenal posterior wall. Following endoscopic hemostasis, a biopsy was obtained for pathological evaluation. The lesion was subsequently confirmed to be a duodenal NK/T-cell lymphoma. The presenting symptoms of primary duodenal NK-/T-cell lymphoma in this patient were abdominal pain and gastrointestinal bleeding, and endoscopy was important for diagnosis. Despite aggressive treatments, the prognosis was very poor.

Hypocrellin D, a cytotoxic fungal pigment from fruiting bodies of the ascomycete Shiraia bambusicola.

A fungal pigment, hypocrellin D (1), together with three known perylenequinone derivatives hypocrellin A (2), B (3) and C (4), was isolated from the fruiting bodies of Shiraia bambusicola. Its structure was elucidated on the basis of spectral data including 2D NMR experiments. Hypocrellin D (1) significantly inhibited the growth of tumor cell lines Bel-7721, A-549 and Anip-973 with IC50 values of 1.8, 8.8, 38.4 microg/ml, respectively.