Sarcopenia in liver cirrhosis: perspectives from epigenetics and microbiota.

Sarcopenia is characterized by the loss of muscle mass and function. It is well known that sarcopenia is often associated with aging, while in recent years, sarcopenia comorbid with chronic diseases such as cirrhosis has attracted widespread attention, whose underlying molecular mechanisms remain unclear. Since cirrhosis and sarcopenia are assumed to be closely interrelated in terms of pathogenesis, this review innovatively discussed the role of epigenetic modifications and microecological dysregulation in sarcopenia in the context of liver cirrhosis. Here we illustrated the relationship between sarcopenia and cirrhosis in the aspect of epigenetics, dysbiosis, and the crosstalk between gene modifications and intestinal microecology. Furthermore, the alterations in cirrhosis patients with sarcopenia, such as inflammatory response and oxidative stress, are found to present synergistic effects in the pathways of epigenetics and dysbiosis leading to sarcopenia. This review proposes that microbiome-based therapies are promising to break the vicious cycle between epigenetic modification and dysbiosis, providing strong support for the use of intestinal microecological interventions to prevent sarcopenia in cirrhotic patients.

BARX2 expression is downregulated by CpG island hypermethylation and is associated with suppressed cell proliferation and invasion of gastric cancer cells.

BarH­like homeobox 2 (BARX2), a homeobox gene, is associated with several types of cancers. The present study aimed to determine whether DNA methylation downregulates BARX2 expression and whether BARX2 is associated with suppression of gastric carcinogenesis. BARX2 protein expression in normal and cancerous gastric tissues and various gastric cancer (GC) cell lines was detected using immunohistochemical and western blot assays. BARX2 mRNA levels were detected using both reverse transcription­polymerase chain reaction (RT­PCR) and quantitative PCR (qPCR). Promoter hypermethylation in GC cells was detected using methylation­specific PCR or bisulfite DNA sequencing PCR. Effects of BARX2 expression on GC cell proliferation, clonal formation, and migration were evaluated after lentivirus­BARX2 transfection. The effect of stable BARX2 transfection on tumor formation was assessed in a nude xenograft mouse model. BARX2 was strongly expressed in the normal gastric mucosa, but weakly or not expressed in GC tissues and most GC cell lines. BARX2 expression was negatively correlated with DNMT (a marker for DNA methylation) expression in the gastric tissues. The BARX2 promoter fragment was hypermethylated in the GC cell lines. Overexpression of BARX2 significantly inhibited GC cell proliferation, clonal formation, and migration. Stable BARX2 transfection inhibited tumor formation in xenograft mice, which was correlated with decreased expression of E­cadherin, proliferation markers, and matrix metalloproteinases. In conclusion, BARX2 expression is aberrantly reduced in GC, which is associated with increased DNA methylation of its promoter. BARX2 inhibits GC cell proliferation, migration, and tumor formation, suggesting that BARX2 acts as a tumor suppressor in gastric carcinogenesis.

Potential involvement of heat shock proteins in pancreatic-duodenal homeobox-1-mediated effects on the genesis of gastric cancer: A 2D gel-based proteomic study.

AIM: To identify functional proteins involved in pancreatic-duodenal homeobox-1 (PDX1)-mediated effects on gastric carcinogenesis. METHODS: A PDX1-overexpressed model was established by transfecting gastric cancer cell line SGC7901 with pcDNA3.1(+)-PDX1 vector (SGC-PDX1). Transfection with empty pcDNA3.1 vector (SGC-pcDNA) served as control. Comparative protein profiles of the two groups were analyzed by two-dimensional electrophoresis based-proteomics (2DE gel-based proteomics). The differential proteins identified by 2DE were further validated by qRT-PCR and immunoblotting. Finally, co-immunoprecipitation was used to determine any direct interactions between PDX1 and the differential proteins. RESULTS: 2DE gel proteomics identified seven differential proteins in SGC-PDX1 when compared with those in SGC-pcDNA. These included four heat shock proteins (HSPs; HSP70p1B, HSP70p8, HSP60, HSP27) and three other proteins (ER60, laminin receptor 1, similar to epsilon isoform of 14-3-3 protein). Immunoblotting validated the expression of the HSPs (HSP70, HSP60, HSP27). Furthermore, their expressions were lowered to 80%, 20% and 24%, respectively, in SGC-PDX1, while PDX1 exhibited a 9-fold increase, compared to SGC-pcDNA. However, qRT-PCR analysis revealed that mRNA levels of the HSPs were increased in SGC-PDX1, suggesting that the expression of the HSPs was post-translationally regulated by the PDX1 protein. Finally, co-immunoprecipitation failed to identify any direct interaction between PDX1 and HSP70 proteins. CONCLUSION: This study demonstrates the potential involvement of HSPs in PDX1-mediated effects on the genesis of gastric cancer.

[Preparation of As2O3 nanoparticles and its drug release characteristics in vitro].

OBJECTIVE: To prepare arsenic trioxide (As2O3)-loaded biodegradable polylactic-co-glycolic acid (PLGA) nanoparticles (NPS) and evaluate the glomeration ability, appearance, structure, surface and release characteristics of the NPs. METHODS: With PLGA as the carrier material, As2O3 NPs (As2O3-NPS) were prepared with the method of matrix and ultrasound emulsification. According to the criteria of the diameter of the NPs, drug loading (DL) and embedding ratio (ER), the process of NP preparation was optimized by scanning electron microscopy (SEM), ultraviolet spectroscopy (UV), and XPS. RESULTS: The As2O3-NPS prepared were uniformly spherical with an average diameter of 210-/+23 nm, DL of 29.6% and ER of 82.1%. The drug release assay in vitro showed a sustained drug-release capacity of the preparation. CONCLUSION: As2O3-NPS may serve as a carrier of As2O3 to change the pharmacokinetics of As2O3 in vivo, allow slow drug release, and prolong the drug circulation time after intravenous injection, thereby producing better antitumor effects.

[Clinical features of panereatic disease-associated portal hypertension].

OBJECTIVE: To investigate the clinical features and management of pancreatic disease-associated portal hypertension. METHODS: A retrospective analysis was carried out in patients with portal hypertension and concurrent pancreatic diseases. The medical records of these patients were reviewed including the data of demographics, etiologies, venous involvement, clinical presentations, laboratory tests, imaging studies, therapeutic modalities and outcomes. RESULTS: Fifty-two patients with portal hypertension resulting from pancreatic diseases were found in our hospital, accounting for 4% of all the patients with portal hypertension in 11 years. The underlying pancreatic diseases were chronic pancreatitis (21 cases, 35.6%), pancreatic carcinoma (20 cases, 33.9%), acute pancreatitis (8 cases, 13.6%), pancreatic pseudocyst (3 cases, 5.1%). Of the 40 patients whose venous involvement was identified, splenic vein obstruction occurred in 27 cases (67.5%) and portal vein obstruction in 16 cases (40.0%). Mild or moderate splenomegaly was present in 48 cases (81.4%), with leukocytopenia as the most common manifestation of the 31 cases (52.5%) with concomitant hypersplenism. Forty-five patients (76.3%) developed gastroesophageal varices (including 35 with isolated gastricvarices), and among them 22 experienced bleeding (42.3%). Conservative treatment was effective in controlling acute bleeding, but could not prevent re-bleeding. Splenectomy was performed in 18 patients mainly due to gastrointestinal hemorrhage. No postoperative bleeding occurred during the follow-up ranging from 8 months to 9 years. CONCLUSION: Pancreatic diseases may compromise portal vein and its tributaries, leading to generalized or regional portal hypertension. Pharmacological therapy can effectively control acute variceal bleeding, while surgical treatment is the appropriate procedure of choice in case of hemorrhagic recurrence.