Downregulation of ASPP2 in pancreatic cancer cells contributes to increased resistance to gemcitabine through autophagy activation.

BACKGROUND: Apoptosis-stimulating of p53 protein 2 (ASPP2) is one of the ASPP family members and it has been reported to be associated with human cancer. However, the role of it in pancreatic cancer is still not clear. METHODS: We analyzed the expression level of ASPP2 in cancer tissue samples with RT-qPCR, Western Blotting assay and immunohistochemistry staining. We studied the biological function of ASPP2 and its mechanism with gene overexpression and gene silencing technologies. We determined the sensitivity of pancreatic cells with differential ASPP2 level to gemcitabine and whether autophagy inhibition affected the gemcitabine resistance, both in vitro and in vivo. RESULTS: Expression of ASPP2 was downregulated in cancerous tissues in comparison with para-cancerous tissues. ASPP2 expression was linked to clinical outcomes in patients and down-regulation of ASPP2 increased cell proliferation, autophagic flux, the activity of AMP Kinase of pancreatic cancer cells and vice versa. Knockdown of ASPP2 results in increased resistance to gemcitabine, which was attributed to the enhanced autophagy. CONCLUSIONS: ASSP2 expression is lower in cancerous tissues and decreased ASPP2 lead to higher cancer cells proliferation and autophagic flux, which contribute to the gemcitabine resistance.

Sox2 function as a negative regulator to control HAMP expression.

BACKGROUND: Hepcidin, encoding by HAMP gene, is the pivotal regulator of iron metabolism, controlling the systemic absorption and transportation of irons from intracellular stores. Abnormal levels of HAMP expression alter plasma iron parameters and lead to iron metabolism disorders. Therefore, it is an important goal to understand the mechanisms controlling HAMP gene expression. RESULTS: Overexpression of Sox2 decrease basal expression of HAMP or induced by IL-6 or BMP-2, whereas, knockdown of Sox2 can increase HAMP expression, furthermore, two potential Sox2-binding sites were identified within the human HAMP promoter. Indeed, luciferase experiments demonstrated that deletion of any Sox2-binding site impaired the negative regulation of Sox2 on HAMP promoter transcriptional activity in basal conditions. ChIP experiments showed that Sox2 could directly bind to these sites. Finally, we verified the role of Sox2 to negatively regulate HAMP expression in human primary hepatocytes. CONCLUSION: We found that Sox2 as a novel factor to bind with HAMP promoter to negatively regulate HAMP expression, which may be further implicated as a therapeutic option for the amelioration of HAMP-overexpression-related diseases, including iron deficiency anemia.

Schisandrin B Improves the Hypothermic Preservation of Celsior Solution in Human Umbilical Cord Mesenchymal Stem Cells.

BACKGROUND: Human umbilical cord mesenchymal stem cells (hUCMSCs) have emerged as promising therapy for immune and inflammatory diseases. However, how to maintain the activity and unique properties during cold storage and transportation is one of the key factors affecting the therapeutic efficiency of hUCMSCs. Schisandrin B (SchB) has many functions in cell protection as a natural medicine. In this study, we investigated the protective effects of SchB on the hypothermic preservation of hUCMSCs. METHODS: hUCMSCs were isolated from Wharton's jelly. Subsequently, hUCMSCs were exposed to cold storage (4 °C) and 24-h re-warming. After that, cells viability, surface markers, immunomodulatory effects, reactive oxygen species (ROS), mitochondrial integrity, apoptosis-related and antioxidant proteins expression level were evaluated. RESULTS: SchB significantly alleviated the cells injury and maintained unique properties such as differentiation potential, level of surface markers and immunomodulatory effects of hUCMSCs. The protective effects of SchB on hUCMSCs after hypothermic storage seemed associated with its inhibition of apoptosis and the anti-oxidative stress effect mediated by nuclear factor erythroid 2-related factor 2 signaling. CONCLUSION: These results demonstrate SchB could be used as an agent for hypothermic preservation of hUCMSCs.

Nomogram predicts CR-POPF in open central pancreatectomy patients with benign or low-grade malignant pancreatic neoplasms.

Introduction: Central pancreatectomy (CP) is a standard surgical procedure for benign and low-grade malignant pancreatic neoplasms in the body and neck of the pancreas. Higher incidence of clinically relevant postoperative pancreatic fistula (CR-POPF) after CP than after pancreaticoduodenectomy (PD) or distal pancreatectomy (DP) has been reported, but no nomogram for prediction of CR-POPF after open CP has been previously established. Methods: Patients undergoing open CP for benign or low-grade malignant pancreatic neoplasms in the department of Hepatobiliary and Pancreatic (HBP) surgery of Shanghai Changhai Hospital affiliated to Naval Medical University between January 01, 2009 and December 31,2020 were enrolled. Pre-, intra- and post-operative parameters were analyzed retrospectively. Results: A total of 194 patients, including 60 men and 134 women, were enrolled with median age of 52 years (21~85 years). 84 patients (43.3%) were overweight (BMI>23.0 Kg/m2) and 14 (7.2%) were obese (BMI>28.0 Kg/m2). Pathological diagnoses ranged from serous cystic neoplasm (32.5%), solid pseudopapillary neoplasm (22.2%), pancreatic neuroendocrine tumor (20.1%), intraductal papillary mucinous neoplasm (18.0%) to mucinous cystic neoplasm (5.2%). All patients had soft pancreatic texture. Main pancreatic duct diameters were ≤0.3cm for 158 patients (81.4%) and were ≥0.5cm in only 12 patients (6.2%). A stapler (57.7%) or hand-sewn closure (42.3%) were used to close the pancreatic remnant. The pancreatic anastomosis techniques used were duct to mucosa pancreaticojejunostomy (PJ)-interrupted suture (47.4%), duct to mucosa PJ-continuous suture (43.3%), duct to mucosa "HO" half-purse binding PJ (5.2%) and invaginating pancreaticogastrostomy (4.1%). Post-surgical incidences of CR-POPF of 45.9%, surgical site infection of 28.9%, postpancreatectomy hemorrhage of 7.7% and delayed gastric emptying of 2.1% were found. Obesity and pancreatic anastomosis technique were independent risk factors of CR-POPF, with a concordance index of 0.675 and an Area Under the Curve of 0.678. Discussion: This novel nomogram constructed according to obesity and pancreatic anastomosis technique showed moderate predictive performance of CR-POPF after open CP.

[Rare variation of abdominal aorta breaking in two].

OBJECTIVE: To discuss a rare variation of abdominal aorta breaking in two. METHODS: An in-patients, female, aged 76, admitted for asthenia of right extremities, underwent gadolinium-enhanced magnetic resonance angiography (MRA) of cerebral and abdominal vessels and abdominal MRI in whom the conventional angiography had failed to reveal this vascular abnormality. RESULTS: MRA showed a clearly separated abdominal aorta. The upper part of the abdominal aorta terminated under the two renal artery branches and the lower part terminated at the level of L(3 - 4). The compensated enlarged superior and inferior mesenteric artery connected these two isolated parts of abdominal aorta. CONCLUSION: This rare variation of abdominal aorta without any symptom is probably caused by some external force during the embryonic period.

Ulinastatin reduces the resistance of liver cancer cells to epirubicin by inhibiting autophagy.

During chemotherapy, drug resistance caused by autophagy remains a major challenge to successful treatment of cancer patients. The purpose of this study is to show that ulinastatin (UTI), a trypsin inhibitor, could reduce the resistance of liver cancer cells to chemotherapeutic agent epirubicin (EPI). We achieved this conclusion by analyzing the effect of EPI alone or UTI plus EPI on SMMC-7721 and MHCC-LM3 liver cancer cells. We also generated an EPI-resistant liver cancer cell line (MHCC-LM3er cells), and found that UTI could sensitize the LM3er cells to EPI. Autophagy usually functions to protect cancer cells during chemotherapy. Our study showed that UTI inhibited the autophagy induced by EPI in liver cancer cells, which promoted apoptosis, and therefore, reduced the resistance of the cancer cells to EPI. Further studies showed that the UTI-mediated inhibition on autophagy was achieved by inhibiting transcriptional factor nuclear factor-κB (NF-κB) signaling pathway. To verify our results in vivo, we injected MHCC-LM3 liver cancer cells or EPI-resistant LM3er cells into mice, and found that EPI could only effectively inhibit the growth of tumor in MHCC-LM3 cell-injected mice, but not in LM3er cell-injected mice. However, when UTI was also administered, the growth of tumor was inhibited in the MHCC-LM3er cell-injected mice as well. Our results suggest that UTI may be used in combination with anti-cancer drugs, such as EPI, to improve the outcome of cancer therapy.

[Effect of hyperbaric oxygen on the expression of nitric oxide synthase mRNA in cortex after acute traumatic cerebral injury].

OBJECTIVE: To investigate the effect of hyperbaric oxygen (HBO) treatment on the expression of nitric oxide synthase (NOS) mRNA in cortex after acute traumatic cerebral injury, and to study the mechanism of HBO on brain injury. METHODS: Acute traumatic brain injury model was established with rest received free fall injury method in SD rats. 0.25 MPa HBO treatment was used 1 h or 12 h after brain injury and the cortex was isolated 6 h or 24 h after brain injury respectively. The expression of mRNA coding for nNOS, eNOS or iNOS were assayed using reverse transcription polymerase chain reaction (RT-PCR). RESULTS: The expression of nNOS, eNOS and iNOS mRNA were significantly decreased in 0.25 MPa HBO treatment groups than those in acute cerebral injury groups (P < 0.01). The amount of nNOS, eNOS and iNOS mRNA was significantly lower in HBOT 24 h group than those in HBOT 6 h group (P < 0.05, P < 0.01). There was no significantly difference among nNOS, eNOS and iNOS mRNA in 0.25 MPa normoxic hyperbaric nitrogen groups and acute cerebral injury groups (P > 0.05). CONCLUSION: HBO may exert significant effects on the expression of nNOS mRNA/iNOS mRNA and protect cortical neuronal from traumatic cerebral injury.

Menin prevents liver steatosis through co-activation of peroxisome proliferator-activated receptor alpha.

Fatty liver is strongly associated with metabolic syndrome. Here, we show that the impaired hepatic expression of menin, the product of the MEN1 (multiple endocrine neoplasia type 1) tumor suppressor gene, represents a common feature of several fatty liver mouse models. The liver specific ablation of MEN1 gene expression in healthy mice induced hepatic steatosis under high-fat dietary conditions. Moreover, overexpression of menin in livers of steatotic db/db mice reduced liver triglyceride accumulation. At the molecular level, we found that menin acts synergistically with the nuclear receptor PPARα to control gene expression of fatty acid oxidation. Collectively, these data suggest a crucial role for menin as an integrator of the complex transcriptional network controlling hepatic steatosis.

Sox2 function as a negative regulator to control HAMP expression

BACKGROUND: Hepcidin, encoding by HAMP gene, is the pivotal regulator of iron metabolism, controlling the systemic absorption and transportation of irons from intracellular stores. Abnormal levels of HAMP expression alter plasma iron parameters and lead to iron metabolism disorders. Therefore,itis animportant goal to understand the mechanisms controlling HAMP gene expression. RESULTS: Overexpression of Sox2 decrease basal expression of HAMP or induced by IL-6 or BMP-2, whereas, knockdown of Sox2 can increase HAMP expression, furthermore, two potential Sox2-binding sites were identified within the human HAMP promoter. Indeed, luciferase experiments demonstrated that deletion of any Sox2-binding site impaired the negative regulation of Sox2 on HAMP promoter transcriptional activity in basal conditions. ChIP experiments showed that Sox2 could directly bind to these sites. Finally, we verified the role of Sox2 to negatively regulate HAMP expression in human primary hepatocytes. CONCLUSION: We found that Sox2 as a novel factor to bind with HAMP promoter to negatively regulate HAMP expression, which may be further implicated as a therapeutic option for the amelioration of HAMP-overexpression-related diseases, including iron deficiency anemia.