Hou-Quan Tao

SPARC Is Associated with Gastric Cancer Progression and Poor Survival of Patients

Purpose: The present study investigated the clinical significance of secreted protein, acidic and rich in cysteine (SPARC), in the development and progression of gastric cancer. Experimental Design: Immunohistochemistry was used to analyze SPARC, integrin β1, and matrix metalloproteinase (MMP)-2 expression in 436 clinicopathologically characterized gastric cancer cases. Results: SPARC, integrin β1, and MMP-2 protein levels were upregulated in gastric cancer lesions compared with adjacent noncancerous tissues. SPARC protein was detected in 334 of 436 human gastric cancer cases and was highly expressed in 239 tumors. We also found a positive correlation between expression of SPARC and MMP2, and SPARC and integrin β1. In stages I, II, and III, the 5-year survival rate of patients with a high expression of SPARC was significantly lower than those in patients with low expression. In stage IV, SPARC expression did not correlate with the 5-year survival rate. Further multivariate analysis suggested that the depth of invasion; lymph node and distant metastasis; tumor-node-metastasis stage; and upregulation of SPARC, MMP-2, and integrin β1, were independent prognostic indicators for the disease. Conclusions: Our study provided a basis for the development of a novel biomarker for diagnosis and prognosis of gastric cancer. Expression of SPARC in gastric cancer is significantly associated with lymph node and distant metastasis, high MMP2 expression, high intergrin β1 expression, and poor prognosis. SPARC, intergrin β1, and MMP-2 protein could be useful markers to predict tumor progression. Clin Cancer Res; 16(1); 260–8

Recurrent TERT promoter mutations identified in a large-scale study of multiple tumour types are associated with increased TERT expression and telomerase activation

BACKGROUND Several somatic mutation hotspots were recently identified in the telomerase reverse transcriptase (TERT) promoter region in human cancers. Large scale studies of these mutations in multiple tumour types are limited, in particular in Asian populations. This study aimed to: analyse TERT promoter mutations in multiple tumour types in a large Chinese patient cohort, investigate novel tumour types and assess the functional significance of the mutations. METHODS TERT promoter mutation status was assessed by Sanger sequencing for 13 different tumour types and 799 tumour tissues from Chinese cancer patients. Thymic epithelial tumours, gastrointestinal leiomyoma, and gastric schwannoma were included, for which the TERT promoter has not been previously sequenced. Functional studies included TERT expression by reverse-transcriptase quantitative polymerase chain reaction (RT-qPCR), telomerase activity by the telomeric repeat amplification protocol (TRAP) assay and promoter activity by the luciferase reporter assay. RESULTS TERT promoter mutations were highly frequent in glioblastoma (83.9%), urothelial carcinoma (64.5%), oligodendroglioma (70.0%), medulloblastoma (33.3%) and hepatocellular carcinoma (31.4%). C228T and C250T were the most common mutations. In urothelial carcinoma, several novel rare mutations were identified. TERT promoter mutations were absent in gastrointestinal stromal tumour (GIST), thymic epithelial tumours, gastrointestinal leiomyoma, gastric schwannoma, cholangiocarcinoma, gastric and pancreatic cancer. TERT promoter mutations highly correlated with upregulated TERT mRNA expression and telomerase activity in adult gliomas. These mutations differentially enhanced the transcriptional activity of the TERT core promoter. CONCLUSIONS TERT promoter mutations are frequent in multiple tumour types and have similar distributions in Chinese cancer patients. The functional significance of these mutations reflect the importance to telomere maintenance and hence tumourigenesis, making them potential therapeutic targets.

Up-regulated miR-199a-5p in gastric cancer functions as an oncogene and targets klotho

BackgroundRecent studies have shown that miR-199a-5p plays opposite roles in cancer initiation and progression of different cancer types, acting as oncogene for some cancer types but as tumor suppressor gene for others. However, the role and molecular mechanism of miR-199a-5p in gastric cancer are largely unknown.MethodsIn this study, miR-199a-5p expression level in gastric cancer was first analyzed by qPCRand then validated in 103 gastric cancer patients by in situ hybridization (ISH). Gastric cancer cell lines were transfected with miR-199a-5p inhibitor and mimic, and underwent in vitro transwell assays. Target genes (klotho) were identified using Luciferase reporter assay. Immunohistochemical staining was also used to investigate on how miR-199a-5p regulates the tumour-suppressive effects of klotho in gastric cancer.ResultsIn our present study, we found that miR-199a-5p level was significantly increased in gastric cancer tissues compared to paired normal tissues. We observed that miR-199a-5p could promote migration and invasion of gastric cancer cells. In situ hybridization of miR-199a-5p also confirmed that higher miR-199a-5p expression level was associated with increased likelihood of lymph node metastasis and later TNM stage. Luciferase reporter assay and immunohistochemistry revealed that klotho might be the downstream target of miR-199a-5p.ConclusionsOur present study suggests that miR-199a-5p acts as an oncogene in gastric cancer and functions by targeting klotho.

High-Level Expression of S100A4 Correlates with Lymph Node Metastasis and Poor Prognosis in Patients with Gastric Cancer

BackgroundThe present study investigated the clinical significance of S100 calcium binding protein A4 in the development, progression, and metastasis of gastric cancer.MethodsTumor tissue, adjacent normal tissue, and lymph node and peritoneal metastases were obtained from patients with gastric cancer, and their gene expression profiles were analyzed by Affymetrix GeneChip® HG-U133A2.0 array. The expression of S100A4 was detected by real-time quantitative reverse-transcription polymerase chain reaction (RT-PCR) in gastric tumor tissue and lymph node and peritoneum metastasis. Immunohistochemistry was employed to analyze S100A4 expression in 436 clinicopathologically characterized gastric cancer cases and in corresponding distant metastases from 61 patients.ResultsA total of 434 genes and 169 expressed sequence tags were upregulated by at least twofold in the tumor tissue. The expression of S100A4 in lymph node and peritoneal metastases was significantly higher than that in gastric tumor tissue. The expression of S100A4 messenger RNA (mRNA) or protein differed significantly among gastric tumor tissue, matched normal gastric mucosa, and lymph node and peritoneal metastases. Further multivariate analysis suggested that depth of invasion, lymph node and distant metastases, tumor–node–metastasis (TNM) stage, and upregulation of S100A4 were independent prognostic indicators for the disease.ConclusionGene expression profiles are a useful way to perform simultaneously large-scale analysis of the expression level of thousands of genes. Expression of S100A4 in gastric cancer is associated significantly with lymph node and distant metastases, and poor prognosis. S100A4 may be a useful marker to predict development, progression, and metastasis of gastric cancer.

ADAM 10 is associated with gastric cancer progression and prognosis of patients

The metalloproteinase domain‐containing protein 10 (ADAM 10) has been implicated in the development and progression of gastric cancer.

Clinicopathologic significance of miR-10b expression in gastric carcinoma

We have investigated microRNA (miRNA) expression profiles of gastric cancer and the clinicopathologic significance of miR-10b expression in gastric carcinoma. miRCURY LNA Arrays (v.16.0; Exiqon, Vedbaek, Denmark) were used to screen miRNAs in 17 gastric cancers. Reverse transcriptase polymerase chain reaction was performed to determine the expression of miR-10b in 56 gastric tumors. Expression of miR-10b in 436 paraffin-embedded cancer tissues was also investigated. In gastric cancer, 49 miRNAs were overexpressed by 2.0-fold or greater, and 39 miRNAs were down-regulated by 1.5-fold or greater, whereas miR-10b was up-regulated by 2.98-fold. miR-10b was highly expressed in gastric cancer and correlated with size of tumor, Lauren classification, depth of invasion, lymph node and distant metastasis, TNM stage, and prognosis. In stages I, II, and III, the 5-year survival rate of patients with high levels of miR-10b expression was significantly lower than that in patients with low levels of expression. In stage IV, the expression level of miR-10b did not correlate with the 5-year survival rate. miR-10b may play an important role in progression and prognosis of gastric cancer.

Inducible nitric oxide synthase expression correlates with angiogenesis, lymphangiogenesis, and poor prognosis in gastric cancer patients ☆

Increased nitric oxide synthase expression plays a key role in tumor progression. To examine inducible nitric oxide synthase expression and its correlation with clinical variables, such as tumor progression, angiogenesis, lymphangiogenesis, and prognosis in gastric cancer, we studied inducible nitric oxide synthase expression in gastric cancer samples from 211 patients with 5-year follow-up. CD105 and D2-40 were adopted as biomarkers for tumor angiogenesis and lymphangiogenesis, respectively. Inducible nitric oxide synthase staining was mainly found in the cytoplasm of gastric cancer tumor cells. Positive inducible nitric oxide synthase immunoreactivity was seen in 54.03% of gastric cancer specimens, which was correlated with lymph node metastasis, vascular invasion, distant metastasis, and TNM stage. Compared with inducible nitric oxide synthase negative patients, inducible nitric oxide synthase-positive patients had significantly shorter survival times and higher microvessel density and lymphatic vessel density. Intratumor and peritumor blood microvessel density and lymphatic vessel density correlated with inducible nitric oxide synthase expression (Spearman ρ test, P < .05). We conclude that inducible nitric oxide synthase expression correlates with lymph node metastasis, vascular invasion, distant metastasis, TNM stage, and poor survival rate in gastric cancer. We propose that synthesized inducible nitric oxide synthase increases angiogenesis, and lymphangiogenesis thus promotes tumor progression. Inducible nitric oxide synthase expression may be a good biomarker for poor prognosis in gastric cancer.

Overexpression of matrix metalloproteinase 11 in human gastric carcinoma and its clinicopathologic significance.

Matrix metalloproteinase 11 (stromelysin-3) has recently been reported to play a key role in human tumor progression and poor clinical outcome. The aim of this study was to investigate the significance of matrix metalloproteinase 11 expression in gastric cancer. Using real-time quantitative reverse-transcription polymerase chain reaction analysis and immunohistochemistry, we studied matrix metalloproteinase 11 expression levels in non-malignant gastric tissues and in gastric cancer tissues. The association between matrix metalloproteinase 11 expression levels and tumor stage and grade, as well as metastatic potential, was analyzed. Our results show that matrix metalloproteinase 11 expression was significantly higher in gastric cancer specimens compared with nonmalignant tissues at both transcriptional and protein levels, indicating its positive role in the development of gastric cancer. In addition, increased matrix metalloproteinase 11 expression levels were associated with advanced-stage and high-grade tumors, suggesting its involvement in the progression of gastric cancer. More importantly, increased matrix metalloproteinase 11 expression in gastric cancer specimens was correlated with increased expression of IGF-1, a molecule known to stimulate the proliferation, enhanced survival, and migration of cancer cells. Our results demonstrate that matrix metalloproteinase 11 is a novel factor in the development and progression of gastric cancer and suggest that matrix metalloproteinase 11 is a marker for advanced gastric cancer.

Expression of Matrix Metalloproteinase‐9 mRNA and Vascular Endothelial Growth Factor Protein in Gastric Carcinoma and Its Relationship to Its Pathological Features and Prognosis

To investigate matrix metalloproteinase‐9 (MMP‐9) mRNA and vascular endothelial growth factor (VEGF) protein expression in gastric carcinoma and its correlation with microvascular density, growth‐pattern, invasion, metastasis, and prognosis. In situ hybridization of MMP‐9 mRNA and immunohistochemistry of VEGF and CD34 proteins were performed on surgical specimens of gastric cancers from 118 patients compared with 20 nonmalignant gastric mucosae. Their relationships to pathological parameters and survival times were determined by statistical analysis. The positive rate of MMP‐9 in noncancerous gastric mucosae was significantly lower than that of gastric cancer tissue (60.17%, P < 0.01). In patients with cancers of the infiltrating type, at stage T3‐T4, with vessel invasion, lymphatic metastasis, hepatic, or peritoneal metastasis, the positive expression rates of MMP‐9 mRNA, VEGF protein, and CD34 were significantly higher than those for patients with tumors of the expanding type (P < 0.01), at stage T1–T2 (P < 0.01), with nonvessel invasion (P < 0.05), without lymphatic metastasis (P < 0.05), and without hepatic (P < 0.001) or peritoneal metastasis (P < 0.001), respectively. Expression of MMP‐9 mRNA was positively related to that of VEGF protein (P < 0.001) and microvascular density (P < 0.001). Patients with higher MMP‐9 mRNA and VEGF expression demonstrated vivid tumor angiogenesis and poor 5‐year survival rate. MMP‐9 and VEGF expression is associated with enhanced tumor angiogenesis and may play crucial roles in the invasion and metastasis of gastric carcinoma. Therefore, MMP‐9 and VEGF may represent prognostic biomarkers and promising targets for therapeutic intervention. Anat Rec, 2010.

Expressions of Neutrophil Gelatinase‐Associated Lipocalin in Gastric Cancer: A Potential Biomarker for Prognosis and an Ancillary Diagnostic Test

The aim of this study was to explore the clinical significance of neutrophil gelatinase‐associated lipocalin (NGAL) in the development and prognosis of gastric cancer. NGAL tumor levels were determined in 333 GC patients by immunohistochemistry. NGAL in blood samples from 63 healthy donors and 60 gastric cancer patients were also determined by enzyme‐linked immunosorbent assay. Rate of NGAL expression was correlated with the size of tumor (69.3% in >4 cm tumors vs. 46.1% in ≤4 cm tumors), Laurens classification (84.3% in diffuse type vs. 28.2% in intestinal type), lymph node metastasis (75.6% vs. 16.4% with no metastasis), vascular invasion (74.9% vs. 26.8% with no invasion), distant metastasis (94.3% vs. 50.3% with no distant metastasis), and TNM stage (81.8% in TNM III+IV vs. 20.5% in TNM I+II). NGAL expression can be used as an independent prognostic factor in gastric cancer as indicated by multivariate analysis. Positivity for serum NGAL was higher than that for carbohydrate antigen determinant, CA19‐9 (38.1% vs. 12.5%) in TNM I, and higher than that for carcinoembryonic antigen, CEA (58.3% vs. 8.3%) and CA19‐9 (58.3% vs. 8.3%) in TNM II. In conclusion, serum NGAL has great potential to be used as an ancillary test for diagnosis of gastric cancer. Increased expression of NGAL in tumors suggests gastric cancer is likely to be at an advanced stage with invasion and metastasis, and also poor prognosis. Anat Rec, 2010.