Skin Ultrastructure and the Changes of HIF-2α, H-FABP Expression in the Myocardium of Electric Shock Death Rats / 法医学杂志

Objective To observe the skin ultrastructure change of electric shock death rats and to test the expression changes of hypoxia-inducible factor-2α （HIF-2α） and heart type-fatty acid-binding protein （H-FABP） of myocardial cells, in order to provide basis for forensic identification of electric shock death. Methods The electric shock model of rats was established. The 72 rats were randomly divided into control group, electric shock death group and postmortem electric shock group. Each group was divided into three subgroups, immediate （0 min）, 30 min and 60 min after death. The skin changes of rats were observed by HE staining, the changes of skin ultrastructure were observed by scanning electron microscopy, and the expression of HIF-2α and H-FABP in rats myocardium was tested by immunohistochemical staining. Results The skin in the electric shock death group and postmortem electric shock group had no significant difference through the naked eye or by HE staining. Under the scanning electron microscope, a large number of cellular debris, cells with unclear boundaries, withered cracks, circular or elliptical holes scattered on the cell surface and irregular edges were observed. A large number of spherical foreign body particles were observed. Compared with the control group, the expression of HIF-2α in all electric shock death subgroups increased, reaching the peak immediately after death. In the postmortem electric shock group, HIF-2α expression only increased immediately after death, but was lower than that of electric shock death group （P<0.05）. Compared with the control group, the expression of H-FABP in all subgroups of electric shock death group and postmortem electric shock group significantly decreased. The expression of H-FABP in all subgroups of electric shock death group was lower than that of the postmortem electric shock group （P<0.05）. Conclusion Electric shock can increase HIF-2α expression and decrease H-FABP expression in the myocardium, which may be of forensic significance for the determination of electric shock death and identification of antemortem and postmortem electric shock.

Effects of hypoxia on expression of hypoxia inducible factors 1α and 2α in human lung cancer cell line A-549 / 实用医学杂志

Objective To investigate the changes of hypoxia-inducible factor (HIF-1α, HIF-2α) expression level in lung cancer A-549 cells under normoxic conditions, different hypoxia durations, and different oxygen concentrations. Methods A549 cells were divided into normoxic group, time control group, and oxygen concentration control group. Western blot was used to detect the expression of HIF-1α and HIF-2α in A-549 cells.Results The expression of HIF-1α and HIF-2α protein were lower under normoxia and significantly increased under hypoxic conditions. The difference was statistically significant. The lower the oxygen concentration, the more HIF-1α and HIF-2α protein expression levels were. The differences between high and high were statistically significant. The expression of HIF-1α protein increased at 2 h after hypoxia, peaked at 8 h, appeared plateau at 8 to 16 h, and decreased at 32 h, with a statistically significant difference. HIF-2α proteins gradually increased with prolonged hypoxia. Conclusions Under hypoxic conditions, the expression of HIF-1α and HIF-2α are increased, and the expression of HIF-2α has a time-dependent pattern, which may have more important biological significance.

Follistatin-like protein 1 plays a tumor suppressor role in clear-cell renal cell carcinoma / 癌症

BACKGROUND@#We previously showed that the expression of follistatin-like protein 1 (FSTL1) was significantly down-regulated in metastatic clear-cell renal cell carcinoma (ccRCC). In this study, we aimed to characterize the role of FSTL1 in the development of ccRCC.@*METHODS@#The effects of FSTL1 on cell activity and cell cycle were investigated in ccRCC cell lines with altered FSTL1 expression. Gene expression microarray assays were performed to identify the major signaling pathways affected by FSTL1 knockdown. The expression of FSTL1 in ccRCC and its effect on postoperative prognosis were estimated in a cohort with 89 patients.@*RESULTS@#FSTL1 knockdown promoted anchorage-independent growth, migration, invasion, and cell cycle of ccRCC cell lines, whereas FSTL1 overexpression attenuated cell migration. FSTL1 knockdown up-regulated nuclear factor-κB (NF-κB) and hypoxia-inducible factor (HIF) signaling pathways, increased epithelial-to-mesenchymal transition, up-regulated interleukin-6 expression, and promoted tumor necrosis factor-α-induced degradation of NF-κB inhibitor (IκBα) in ccRCC cell lines. FSTL1 immunostaining was selectively positive in epithelial cytoplasm in the loop of Henle, and positive rate of FSTL1 was significantly lower in ccRCC tissues than in adjacent renal tissues (P < 0.001). The multivariate Cox regression analysis showed that the intratumoral FSTL1 expression conferred a favorable independent prognosis with a hazard ratio of 0.325 (95% confidence interval 0.118-0.894). HIF-2α expression was negatively correlated with FSTL1 expression in ccRCC specimens (r = - 0.229, P = 0.044). Intratumoral expression of HIF-2α, rather than HIF-1α, significantly predicted an unfavorable prognosis in ccRCC (log-rank, P = 0.038).@*CONCLUSIONS@#FSTL1 plays a tumor suppression role possibly via repressing the NF-κB and HIF-2α signaling pathways. To increase FSTL1 expression might be a candidate therapeutic strategy for metastatic ccRCC.

Advances in differential roles of HIF-1αand HIF-2αin the pathogenesis of hypoxic pulmonary hypertension / 中国药理学通报

Hypoxia-induced factors(HIFs)are the main regula-tors for the response of hypoxic environment.They are involved in hypoxia-related lung tissue cell damage and abnormal cell pro-liferation,among which,HIF-1αand HIF-2αplay the most im-prominant roles.This paper reviews the current researches of HIF-1αand HIF-2α,focusing on their structural and functional similarities and diversities,as well as their roles in the patho-genesis of hypoxic pulmonary hypertension.

Relationships of Raptor and Rictor expression with angiogenesis in colorectal cancer and their clinical significance / 临床与实验病理学杂志

Purpose To detect the expression of Raptor,Rictor,angiogenesis-related factors HIF-lα,HIF-2α and VEGF and to investigate their relationship and significance in eolorectal cancer (CRC).Methods Immunohistochemistry,Western blot and RT-PCR were employed to detect the expression of Raptor,Rictor,HIF-lα,HIF-2α and VEGF in 120 cases of CRC and 60 cases of normal colorectal mucosa.CD34 labeled microvascular density (MVD) was also observed.The correlations between Raptor,Rictor,HIF-1α,HIF-2c,VEGF expression and the patients' clinicopathological features were analyzed.Results The positive rates of Raptor,Rictor,HIF-1c,HIF-2α and VEGF in CRC were significantly higher than those in normal colorectal mucosa (P ＜ 0.05).Raptor and Rictor expression was correlated with the degree of tumor diffcrentiation and lymph node metastasis,respectively.The expression of HIF-1α,HIF2α and VEGF was higher in patients with lymph node metastasis than those in patients without lymph node metastasis (P ＜0.05).The MVD was higher in patients with Raptor or Rictor positive than that in patients with Raptor or Rictor negative (P ＜0.05).The expression of Raptor was positively correlated with HIF-1α and VEGF (P ＜ 0.01),the expression of Rictor was positively correlated with HIF-2o and VEGF (P ＜ 0.01),but the expression of Raptor was negatively correlated with Rictor (P＜0.01).Conclusion The expression of mTOR core molecules Raptor and Rictor is related to the initiation and development of colorectal cancer and angiogenesis,and they promote angiogenesis in colorectal cancer by different ways.

Expression of HIF-1α and HIF-2α in small cell lung cancer stem cells and tissues and their significance / 临床与实验病理学杂志

Purpose To observe the expression of HIF-1αand HIF-2α in tumor stem cells and tumor tissues of small cell lung cancer (SCLC) and to explore their clinical significance.Methods The defined serum-free culture was used to enrich the third passage tumor spheres cells from H446 as the tumor stem cells.Real-time PCR was performed to determine the mR-NA expression level of HIF-1α and HIF-2α in H446 tumor stem cells.Immunofluorescence staining was performed to determine the protein expression level of HIF-1α and HIF-2α in H446 tumor stem cells.Immunohistochemistry SP method was used to detect the expression of HIF-1α and HIF-2αt in SCLC tissues.Results The mRNA expression level of HIF-2α was up-regulated in tumor stem cells.However,the mRNA expression level of HIF-1 α was down-regulated in tumor stem cells (P ＜ 0.05).The expression of HIF-2α protein was positive in tumor stem cells.In contrast,HIF-1α protein was negative in tumor stem cells.In SCLC tissues,the positive rate of HIF-1α was 46.7％ (28/60),and the positive rate of HIF-2α was 25％ (15/60).Correlation analysis showed that HIF-2α was positively correlated with SCLC stem cell marker uPAR,and they co-localized around necrotic regions.The expression of HIF-2α was closely related to tumor diameter and distant metastasis.In contrast,the expression of HIF-1α had no relationship with age,sexy,tumor size,lymph metastasis,pleural invasion and distant metastasis (P ＞ 0.05).Conclusion HIF-2α is up-regulated in SCLC stem cells and positively correlated with SCLC stem cell marker uPAR,which are associated with the tumor diameter and distant metastasis of SCLC patients,suggesting that the expression of HIF-2α may be related to SCLC stem-like characteristics.

The Relationship between HIF-2α and VEGF with Radiographic Severity in the Primary Osteoarthritic Knee

PURPOSE: The aim of this study was to determine the relationship of hypoxia-inducible factor-2 (HIF-2α) and vascular endothelial growth factor (VEGF) with radiographic severity in primary osteoarthritis (OA) of the knee. Expression of these two factors in cartilage samples from OA knee joints was examined at mRNA and protein levels. MATERIALS AND METHODS: Knee joints were examined using plain radiographs, and OA severity was assessed using the Kellgren and Lawrence (KL) grading system. Specimens were collected from 29 patients (31 knees) who underwent total knee replacement because of severe medial OA of the knee (KL grades 3 and 4), 16 patients who underwent knee arthroscopy (KL grade 2), and 5 patients with traumatic knees (KL grade 0). HIF-2α and VEGF expression was quantified by real-time polymerase chain reaction and western blotting. RESULTS: Cartilage degeneration correlated with the radiographic severity grade. OA severity, determined using the Mankin scale, correlated positively with the KL grade (r=0.8790, p<0.01), and HIF-2α and VEGF levels with the radiographic severity of knee OA (r=0.7001, p<0.05; r=0.6647, p<0.05). CONCLUSION: In OA cartilage, HIF-2α and VEGF mRNA and protein levels were significantly and positively correlated. The expression of both factors correlated positively with the KL grade. HIF-2α and VEGF, therefore, may serve as biochemical markers as well as potential therapeutic targets in knee OA.

Expression and significance of HIF-1α and HIF-2α in pancreatic cancer / 华中科技大学学报（医学）（英德文版）

The expression levels of hypoxia-inducible factor 1alpha (HIF-1α) and HIF-2α in pancreatic cancer (PC) and their association with clinicopathologic characteristics were investigated in order to elucidate their roles in the development of PC. HIF-1α and HIF-2α mRNA levels in 20 patients with PC were detected by quantitative real-time polymerase chain reaction. The expression of HIF-1α and HIF-2α protein in samples from other 90 patients with PC was measured by immunohistochemistry. Correlations between the expression of HIF-1α or HIF-2α and clinicopathologica features and prognosis were analyzed. The expression of both HIF-1α and HIF-2α mRNA was up-regulated in most cancer tissues (P<0.05). HIF-1α staining was weakly positive in most cancer tissues and strongly positive in adjacent pancreas tissues (P<0.05). Clinicopathologic analysis revealed that relatively strong HIF-1α expression in cancer tissues was related to greater invasion (P<0.05), higher tumor pathologic stage (P<0.05), higher American Joint Committee on Cancer (AJCC) stage (P<0.05) and shorter overall survival time (P<0.05). Conversely, HIF-2α staining was strongly positive in most cancer tissues and weakly positive in adjacent pancreas tissues. Clinicopathologic analysis revealed that relatively strong HIF-2α expression in cancer tissues was related to less invasion (P<0.05), lower tumor pathologic stage (P<0.05), lower AJCC stage (P<0.05) and longer overall survival time (P<0.05). Moreover, the HIF-1α(high)/HIF-2α(low) group showed a shorter survival time than the HIF-1α(low)/HIF-2α(high) group. In conclusion, although HIF-1α and HIF-2α mRNA expression patterns are the same, their protein expression patterns are significantly different and they play different roles in PC. Combined analysis of HIF-1α and HIF-2α expression might be useful to predict the prognosis of patients with PC.

Expression and significance of HIF-1α, HIF-2αand MT in human papillary thy-roid carcinoma / 中国免疫学杂志

Objective:To investigate the expression of HIF-1α, HIF-2αand MT in human papillary thyroid carcinoma ( PTC) and the association of their expression with clinicopathological indicators .Methods:Immunohistochemistry was used to analyze the ex-pression of HIF-1α, HIF-2αand MT in 70 PTC samples .The correlations of HIF-1α, HIF-2αand MT expression with one another , and with several clinicopathological indicators were statistically analyzed .Results:In 70 PTC samples, the positive expression rates of HIF-1α, HIF-2αand MT were 52.86%(37/70), 50.00%(35/70) and 44.29%(31/70), respectively.HIF-1α, HIF-2αand MT expression had significant correlations with cervical lymph node metastasis (P=0.034, P=0.022, and P=0.032, respectively). Meanwhile, HIF-1αexpression had a positive correlation with HIF-2α(rs =0.258, P=0.031) and MT (rs =0.266, P=0.026). HIF-2αand MT expression were positively correlated (rs=0.259, P=0.030).Concomitant expression of any two or all of the three molecules had stronger correlation with lymph node metastasis than did each alone ( P=0.004 for HIF-1α/HIF-2α, P=0.024 for HIF-1α/MT, P=0.029 for HIF-2α/MT, P=0.017 for HIF-1α/HIF-2α/MT).Conclusion:HIF-1α, HIF-2αand MT expression in PTC samples have a closely correlation , which are related to cervical lymph node metastasis .Therefore, the expression of HIF-1α, HIF-2αand MT might be used as biomarkers for cervical lymph node metastasis of PTC .