Vegetation restoration can effectively enhance soil quality and soil organic carbon (SOC) sequestration. In this study, the distribution characteristics of soil nutrients and SOC along soil profile (0-100 cm), and their responses to restoration years (16, 28, 38 years) were studied in plantations in the southern mountainous area of Ningxia, compared with cropland and natural grassland. The results showed that: 1) the contents of SOC, soil total nitrogen (TN), total phosphorus (TP), particulate organic carbon (POC), mineral-associated organic carbon (MAOC) and the proportion of particulate organic carbon to total organic carbon (POC/SOC) all decreased with increasing soil depth.
View Article and Find Full Text PDFBackground: There have been few studies on the role of autophagy in pancreatic neuroendocrine tumours (PNETs). SQSTM1/p62 (also called Sequestosome 1) is a potential autophagy regulator, and its biological roles and clinical significance in PNETs remain poorly understood.
Purpose: The purpose of this study was to evaluate the clinical significance of SQSTM1/p62 in human PNET specimens and to evaluate its potential value as a therapeutic target by studying its biological function in PNET cell lines.
Background: Gastric cancer (GC) is a common malignant tumor with high incidence and mortality rates globally, especially in East Asian countries. () infection is a significant and independent risk factor for GC. However, its underlying mechanism of action is not fully understood.
View Article and Find Full Text PDFObjective: The clinical significance of the YY1 gene mutation and expression in pancreatic neuroendocrine tumors (PNETs) remains unknown. Therefore, this study aimed to comprehensively analyze the somatic mutation of YY1 in the different subtypes of PNETs.
Methods: A total of 143 PNETs were assessed by Sanger sequencing to identify the somatic mutation of YY1 gene in various subtypes of PNETs.
Background: Insulinoma is a subtype of pancreatic neuroendocrine tumors. Many patients with insulinoma are obese due to frequent food intake. Ghrelin is associated with obesity and blood levels of insulin.
View Article and Find Full Text PDFAberrant blood vessel formation and hemorrhage may contribute to tumor progression and are potential targets in the treatment of several types of cancer. Pancreatic neuroendocrine tumors (PNETs) are highly vascularized, particularly when they are well-differentiated. However, the process of vascularization and endothelial cell detachment in PNETs is poorly understood.
View Article and Find Full Text PDFBackground: Representative data on the gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs) in Asian patients is rare, especially in China. This study aims to create a GEP-NENs profile of Chinese patients.
Methods: This was a hospital-based, nation-wide, and multi-center 10-year (2001-2010) retrospective study which collected GEP-NEN patients' information in tertiary referral hospitals.
Prognostic biomarkers for the pancreatic neuroendocrine tumors are needed. Proteomic study on insulinoma has been rarely reported. We identified the differential expression of proteins between insulinoma and their paired tissues by proteomic analysis, and evaluated the prognostic significance of specific proteins in pancreatic neuroendocrine tumors including insulinoma.
View Article and Find Full Text PDFPolypyrimidine tract-binding protein 1 (PTBP1) involving in almost all steps of mRNA regulation including alternative splicing metabolism during tumorigenesis due to its RNA-binding activity. Initially, we found that high expressed PTBP1 and poor prognosis was interrelated in colorectal cancer (CRC) patients with stages II and III CRC, which widely different in prognosis and treatment, by immunohistochemistry. PTBP1 was also upregulated in colon cancer cell lines.
View Article and Find Full Text PDFObjective: The aim of the study was to address the origin and natural history of malignant insulinoma.
Methods: Retrospective review of medical records of patients diagnosed with insulinoma at Cedars-Sinai Medical Center between 2000 and 2015 was conducted. Hormonal expression in tumor specimens was examined by immunostaining.
The presentation, pathology, and prognosis of pancreatic neuroendocrine tumors (PNETs) in Asian patients have not been studied in large cohorts. We hypothesized that the clinicopathological features of PNETs of Chinese patients might be different from those of US patients. The objectives of this study were to address whether PNETs in Chinese patients exhibit unique clinicopathological features and natural history, and can be graded and staged using the WHO/ENETS criteria.
View Article and Find Full Text PDFThe cells of origin of pancreatic gastrinomas remain an enigma, since no gastrin-expressing cells are found in the normal adult pancreas. It was proposed that the cellular origin of pancreatic gastrinomas may come from either the pancreatic cells themselves or gastrin-expressing cells which have migrated from the duodenum. In the current study, we further characterized previously described transient pancreatic gastrin-expressing cells using cell lineage tracing in a pan-pancreatic progenitor and a pancreatic endocrine progenitor model.
View Article and Find Full Text PDFO(6)-methylguanine-DNA methyltransferase (MGMT) is a widespread DNA repair enzyme defending against mutation caused by guanine O(6)-alkylating agents. Until now, we know only little about the expression of MGMT in gastroenteropancreatic neuroendocrine neoplasm (GEP-NEN). To study the expression of MGMT and its clinical significance in GEP-NEN, 174 specimens of GEP-NEN were examined, of which 152 specimens came from The First Affiliated Hospital, Sun Yat-sen University during October 1995 to November 2013, 22 specimens came from Peking Union Medical College Hospital during September 2004 to April 2010.
View Article and Find Full Text PDFBackground: Pancreatic neuroendocrine tumors (PNETs) are a group of rare tumors. Chromogranin A (CgA) was considered as the most practical and useful serum tumor marker in PNET patients. But peripheral blood levels of CgA are not routinely tested in Chinese patients with PNETs.
View Article and Find Full Text PDFJ Clin Endocrinol Metab
May 2014
Purpose: We aimed to test whether α-internexin could be a molecular biomarker of tumor aggressiveness and prognosis in pancreatic neuroendocrine tumors (PNETs).
Patients And Methods: Using immunohistochemical staining and Western blot, we detected the expression of α-internexin in 350 tumors from 343 patients, of whom 257 were followed up. Methylation of α-internexin promoter was examined by bisulfite sequencing to identify the crucial region that determines gene expression.
Previous studies have shown that S100P contributes to the development of a number of tumors. However, its prognostic significance in colorectal cancer (CRC) has not been demonstrated. This study aimed to confirm the expression of S100P in colorectal cancer as well as the epigenetic mechanism underlying its gene expression, and to demonstrate whether S100P could be used to predict prognosis as a biomarker.
View Article and Find Full Text PDFJ Clin Endocrinol Metab
September 2009
Context: The molecular pathogenesis of sporadic insulinomas is unknown. There is a lack of biomarker to distinguish benign and malignant form of insulinoma.
Objective: Our objective was to confirm the occurrence of microsatellite instability (MSI) in insulinomas, to identify alterations of mismatch repair (MMR) genes in the tumors, and to evaluate the possibility to distinguish benign and malignant insulinoma or to predict the clinical outcome of patients with these alterations.
Objective: To determine the normal value of serum elastase 1 in Chinese adults and evaluate its diagnostic value for pancreatic cancer.
Methods: Serum elastase 1 and CA19-9 were measured in 132 samples, including 39 patients with pancreatic cancer, 48 with other gastrointestinal malignancy, 24 with gastrointestinal benign disease and 21 healthy adults as normal control. Multiple statistical methods including receiver operating characteristics curve and discriminant analysis were employed.
The pathogenesis of sporadic insulinomas is not clear, and there are no reliable genetic determinants that are useful to distinguish malignant and benign forms of this tumor. It was reported that 1q LOH might contribute to pathogenesis in gastrinomas and was correlated with tumor progression. However, little data are available on 1q LOH in sporadic insulinomas.
View Article and Find Full Text PDFObjective: To detecte whether loss of heterozygosity (LOH) at the MEN-1 locus as well as 22q occurs in sporadic insulinoma and if LOH can be used as a genetic marker to differentiate malignant and benign insulinomas.
Methods: MEN-1 gene and 22q allelotyping were performed by PCR with microsatallite markers in DNA from microdissected normal and tumor tissues from archived or frozen insulinomas (8 malignant and 32 benign, from 38 patients). The significance was calculated using t test and Cochran-Mantel-Haenszel Statistics, P < 0.
Objectives: To investigate the differences in morphology, immunohistochemistry, DNA ploidy status, LOH and MSI of 11q13 and 1p between benign and malignant pheochromocytomas, and to find the marker or markers useful in distinction between benign and malignant pheochromocytoma or for predicting the malignant potential of this tumor.
Methods: Twenty-two cases of clinically documented benign and malignant pheochromocytomas from the files of Peking Union Medical College Hospital were analyzed. Aside from histological study, Ki-67, p53, CgA, S-100, PCNA and survivin immunohistochemistry studies were performed.
Background: Recent studies have shown that tumor growth, rather than hormone overproduction, is the leading cause of death among patients with gastrinomas and other malignant gastrointestinal endocrine tumors. No patient/laboratory characteristics accurately predict which tumors will exhibit aggressive growth. Furthermore, little is known regarding the molecular pathogenesis of these tumors.
View Article and Find Full Text PDFPurpose: Recently, an increased incidence of some nonendocrine tumors are reported in patients with multiple endocrine neoplasia type 1 (MEN 1). There are rare reports of meningiomas and other central nervous system tumors in these patients, but it is unknown if they are more frequent or if allelic loss of the MEN1 gene is important in their pathogenesis. The aim of this study was to address these two latter questions.
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