Increased expression of angiogenin in gastric carcinoma in correlation with tumor angiogenesis and proliferation

Abstract

AIM:To investigate the implication of angiogenin (ANG) in the neovascularizaton and growth of human gastric carcinoma (HGC).METHODS: ANG mRNA expression in HGC specimens obtained by surgical resection from patients with HGC were examined by RT-PCR. ANG, Ki-67, VEGF protein expression and microvessel density (MVD) in HGC specimens were detected by immunohistochemistry. RESULTS:RT-PCR showed significantly higher ANG mRNA expression (0.482 ± 0.094) in HGC tissues than in the surrounding nontumorous tissues (0.276 ± 0.019, P = 0.03). MVD within tumorous tissues increased significantly with ANG mRNA expression (r = 0.380, P = 0.001) and ANG protein expression (P < 0.01). The ANG expression levels of cancer tissues were positively correlated with VEGF (P < 0.01) and the proliferation index of cancer cells (P < 0.01). www.wjgnet.com well-moderately differentiated adenocarcinoma, and 41 patients had poorly-undifferentiated adenocarcinoma. Fourteen patients were node-negative; 46 had first station lymph node metastasis, and 8 had second or distant lymph node metastasis. Twelve tumors were TNM Ⅰ, 25 tumors were TNM Ⅱ, 20 tumors were TNM Ⅲ, and 11 tumors were TNM Ⅳ. Methods RNA extraction:Specimens were taken within 30 min after resection, and were stored at -80℃. RNA was extracted from HGC tissue and corresponding nontumorous gastric tissue using Trizol extraction reagent kit (Gibco BRL, USA), according to the instructions of the manual. Concentration and purity of RNA were determined by spectrophotometric method. Integrity of RNA was determined by electrophoresis.RT-PCR and analysis of the products: ANG primers were synthesized by the Bioasia Biotechnology Company using the method as described previously [10] . Each tube contained 5 × buffer 5 μL, 10 mmol/L dNTP 0.5 μL, DTT 1.25 μL, primers (sense, antisense) 4 μL, RNA template 1 μg, mix-enzyme 0.5 μL, DEPC solution, with a total volume of 25 μL (Titan One Tube RT-PCR system, Roche, Ger many). RT-PCR reaction condition is as follows: at 58℃ for reverse transcription for 30 min, 94℃ incubation for 2 min to terminate reverse transcription, followed by 30 cycles at 94℃ for 30 s, at 52℃ for 30 s, and at 72℃ for 60 s; With a final extension at 72℃ for 7 min. RT-PCRs were run in a Bio-rad thermocycler. The results were analysed in a Bio-rad GelDoc-1000 system, relative to the levels of β actin as the control. Immunohistochemistry: ANG multiclonal antibody 1:25 was purchased from American Santa Cruz Co. VEGF-C multiclonal antibody (ready to use) was provided by American Zymed Co. Monoclonal antibody of CD34 (QBEnd/10, ready to use) and monoclonal antibody of Ki-67 (MIB-1, 1:50) were supplied by American NeoMarkers Co. All operations were done according to the instructions of the manufacturers. Positive specimens were used as positive controls and PBS in substitution of the first antibody was used as a negative control at the same time. ANG protein expression [8] : Cytoplasm of gastric carcinoma cells was stained brown. According to the staining intensity of the tum...

Mechanism of Hepatoprotective Effect ofBoesenbergia rotundain Thioacetamide-Induced Liver Damage in Rats

“…In vivo , necrotic death is often associated with extensive damage in the tissue resulting in necro-inflammatory response [42]. Although toxicity induced by TAA was reported to cause upregulation of Bax protein and downregulation of the antiapoptotic protein Bcl-2 and its translocation into the mitochondria, causing apoptosis [43] but other studies suggested that the ROS produced from thioacetamide biotransformation causes centrolobular necrosis [44]. Some Plant extracts such as Curcuma longa extract [4] and some antioxidants such as α -lipoic acid [45], curcumin, and curcuminoids [46] were proved to induce apoptosis.…”

Microvascular density and endothelial area correlate with Ki-67 proliferative index in surgically-treated pancreatic ductal adenocarcinoma patients

“…MVD and EA have been experimentally proposed to be biomarkers associated with biological aggressiveness and clinical outcome in animal and human malignancies. In regards to pancreatic cancer, it has been established that angiogenesis has a role in its development and progression (4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17). In addition, Ki-67 expression is an important parameter for biological aggressiveness and prognosis in tumour tissue; Ki-67 antigens are initially expressed in S-phase and increase throughout S-and G 2 -phase until they reach their peak expression during mitosis.…”

Exploiting Human CD34+ Stem Cell–conditioned Medium for Tissue Repair

“…We found that liver cells treated with TAA displayed severe structural damages, whereas TAA-treated cells that received the conditioned medium maintained normal structural integrity, as well as cell viability ( Figure 4a , b ). As it is known that TAA activates the caspase-3 signaling pathway, 25 we tested for caspase-3 activity under these conditions. We observed a reduced level of caspase-3 activity in liver cells treated with the conditioned medium ( Figure 4c ).…”