Hypoxia occurs in chronic and acute vascular diseases and tumor formation. The ability of tumor cells to maintain a balance between an adaptation to hypoxia and cell death is regulated by a family of transcription factors called hypoxia-inducible factor 1 (HIF-1). Tumor hypoxia mediated by HIF-1 would facilitate the likelihood of resistance to chemotherapy and radiotherapy, proliferation, metastasis and the invasive potential; all of which culminate in a decrease in patient survival. And HIF-1 alpha subunit decides the activity of HIF-1, which is regulated by oxygen. So understanding the role of HIF in signal pathway, drug resistance mechanism and its feature is crucial for developing novel anticancer therapies. In recent years, more attentions have focused on HIF-1 alpha inhibitors. It is expected that development of more potent and selective HIF inhibitors will provide an effective treatment of cancer and other HIF-related diseases. So we will focus on the biological characteristics and mechanism of HIF-1 to review currently studied HIF-1 inhibitors.
Cell Death ; Humans ; Hypoxia-Inducible Factor 1 ; antagonists & inhibitors ; metabolism ; Hypoxia-Inducible Factor 1, alpha Subunit ; antagonists & inhibitors ; metabolism ; Neoplasms ; drug therapy ; Oxygen ; metabolism ; Signal Transduction

Hypoxia occurs in chronic and acute vascular diseases and tumor formation. The ability of tumor cells to maintain a balance between an adaptation to hypoxia and cell death is regulated by a family of transcription factors called hypoxia-inducible factor 1 (HIF-1). Tumor hypoxia mediated by HIF-1 would facilitate the likelihood of resistance to chemotherapy and radiotherapy, proliferation, metastasis and the invasive potential; all of which culminate in a decrease in patient survival. And HIF-1 alpha subunit decides the activity of HIF-1, which is regulated by oxygen. So understanding the role of HIF in signal pathway, drug resistance mechanism and its feature is crucial for developing novel anticancer therapies. In recent years, more attentions have focused on HIF-1 alpha inhibitors. It is expected that development of more potent and selective HIF inhibitors will provide an effective treatment of cancer and other HIF-related diseases. So we will focus on the biological characteristics and mechanism of HIF-1 to review currently studied HIF-1 inhibitors.

Hypoxia is a general characteristic of most solid malignancies and intimately related to cancer progression. Homeostatic response to hypoxia is primarily mediated by hypoxia inducible factor-1alpha (HIF-1alpha) that elicits transcriptional activity through recruitment P300 coactivator. Targeting the interaction of HIF- alpha and P300 would thus constitute a novel approach for cancer treatment by suppressing tumor angiogenesis and metastasis. Here, a screening assay was developed for inhibitors targeting the interaction between HIF-1alpha and P300. The nucleotide sequence of human HIF-1alpha and P300 were cloned into pBIND and pACT vectors, named pBIND-HIF1alpha and pACT-P300. The interaction of HIF-1alpha and P300 was identified in HEK293 cell using mammalian two-hybrid system. And compound chetomin decreased their interaction in this mammalian two-hybrid system. We further verified HIF-1 inhibition effect of chetomin in U251-HRE cells. Therefore, we established a screening assay combined HIF-1alpha and P300 mammalian two-hybrid system and U251-HRE reporter assay for HIF-1 selective inhibitors.

Objective To quantitatively analyze radiation-induced trismus in patients with nasopha-ryngeal carcinoma (NPC) treated by intensity modulated radiation therapy (IMRT), and evaluate tem-poromandibular joint (TMJ) damage. Methods Between February 2001 and October 2004, 211 NPC pa-tients were treated by IMRT, with a total dose of 68 Gy, 2.27 Gy per fraction within 31 -86 days (median, 43 days). The distances between two dens incisivus medialis (DDIM) were measured before and 6 months after IMRT and then annually thereafter. Results The overall survival at 1-, 3-, and 5-year were 97.1%, 90.7% and 79. 1%, respectively. The mean irradiation doses to TMJ were 6.18 -51.36 Gy. Grade 1 TMJ damage was observed in 5.2% patients, and grade 2 occurred in one patients who had received the second course radiotherapy because of local relapse . No grade 3 or 4 TMJ toxicity was observed . Conclusions IMRT can spare the TMJ from high dose irradiation and markedly reduce severe TMJ damage.

Objective To evaluated the value of myocardial perfusion before delayed percutaneous coronary intervention (PCI) for predicting the recovery of systolic function of patients with acute myocardial infarction (AMI).Methods A total of 64 patients with AMI receiving delayed PCI treatment in the First People's Hospital of Foshan from January 2014 to June 2015 were selected.One day prior to delayed PCI,all of the patients underwent two dimensional strain to measure the longitudinal peak systolic strain (LPSS) of each left ventricular segment and the global longitudinal strain (GLS) of the left ventricle.The myocardial perfusion score (MPS) and the perfusion score index (PSI) were measured by myocardial contrast echocardiography (MCE).Left ventricular myocardial perfusions were classified as good,reduced,or absent.The two dimensional strain measurements were again conducted at 6 months after the delayed PCI to assess LPSS and GLS.The change of GLS and LPSS between one day prior to delayed PCI and six months after delayed PCI was assessed by paired t-test.The differences of LPSS among good,reduced,or absent myocardial perfusion groups were analyzed by one-way ANOVA.LSD-t test was used to compare in pairs of groups that had different values.The correlations between PSI and GLS,MPS and LPSS were assessed by Spearman's rank-correlation test.Results The GLS of all patients were higher at six months after delayed PCI than at one day prior to delayed PCI [(-15.39±7.80)％ vs (-12.44±8.38)％,t=14.398,P ＜ 0.001].The LPSS of myocardial perfusion in good,reduced and absent groups at one day prior to delayed PCI were (-2.64±5.60)％,(-6.19±6.87)％ and (-12.07±5.86)％,respectively.The LPSS of myocardial perfusion in good,reduced and absent groups at six months after delayed PCI were (-2.97 ± 4.93)％,(-11.38± 7.26)％ and (-15.82 ± 5.97)％,respectively.The myocardial LPSS of left ventricular segment with good or reduced perfusion was significantly higher at six months after delayed PCI (t=13.013,10.821,both P ＜ 0.001),but the LPSS of left ventricular segment with absent perfusion was similar to that of pre-PCI.Whether at one day prior to delayed PCI or six months after delayed PCI,there were significant differences in LPSS parameters among the three groups (at one day prior to delayed PCI,myocardial perfusion absent vs reduced or good,t=4.201 and 11.771,both P ＜ 0.001;myocardial perfusion reduced vs good,t=12.561,P ＜ 0.001;at six months after delayed PCI,myocardial perfusion absent vs reduced or good,t=9.714 and 15.646,both P ＜ 0.001;myocardial perfusion reduced vs good,t=9.254,P ＜ 0.001).The LPSS both at one day prior to delayed PCI and six months after delayed PCI in myocardial perfusion good group ＞ those of myocardial perfusion reduced group ＞ those of myocardial perfusion absent group.PSI was positively correlated with GLS at both one day prior to delayed PCI and six months after delayed PCI (r=0.69,0.72,both P ＜ 0.001).MPS was positively correlated with LPSS at both one day prior to delayed PCI and six months after delayed PCI (r=0.49 and 0.45,both P ＜ 0.001).Conclusion Myocardial perfusion before delayed PCI,monitored by MCE,is correlated well with myocardial systolic function,and may be used to predict the recovery of myocardial systolic function after delayed PCI.

Objective To study the effect of endothelial progenitor cells (EPCs) transplantation on CCl4 induced hepatic cirrhosis in rats. Methods Eight male SD rats were used as normal control. Thirty rats were induced liver cirrhosis by feeding with 25% CCl4/olive oil for 12 weeks, and then were subdivided into cirrhosis group (n = 10), EPCs transplanted group (n = 10) and saline control group (n = 10). EPCs were transplanted into the portal vein for 4 weeks in EPCs transplanted group. Rats in EPCs nontransplanted group were sacrificed at the beginning of the 12th week. Rats in EPCs transplanted group and saline control group were killed at the beginning of 16th week. Serum biochemical parameters were examined. The degree of liver cirrhosis was evaluated by Masson staining and by detecting the expression of α-SMA, Collagen Ⅲ and Ki67. Results The volumes of liver in cirrhosis group were twice as much as that in normal rats. 12 weeks after CCl4 administration, compared with saline control group, in EPCs transplanted group, hepatic activity index (HAI) ( F = 75. 062, P < 0. 01 ), the levels of ALT( F = 29. 942, P<0.05), AST(F=16.618,P<0.05) and TBIL(F=9.911 ,P<0.05) in serum decreased, the level of Alb ( F = 4. 944, P < 0. 05 ) and Ki67 ( F = 45. 966, P < 0. 01 ) was increased, the expression of α-SM A ( F = 7.86,P<0.05) and collagen Ⅲ (F = 135.787,P <0.01) decreased (P <0.05). Compared with untransplanted group, in EPCs transplanted group, the levels of ALT, AST and TBIL in serum were lower; In saline control group, the levels of ALT, AST and TBIL in serum were higher, the level of Alb and Ki67was lower, the expression of α-SMA and collagen Ⅲ were higher( P < 0. 05 ). Compared with normal rats, in saline control group, the levels of INR were higher (P < 0. 05 ). Conclusion EPCs transplantation improves hepatocye regeneration and ameliorates established hepatic cirrhosis.

Objective To investigate the effect of HBV on the expression of fibrosis-related factors in hepatic stellate cells(HSC)and its relation with liver fibrosis.Methods HSCs were co-cultured with HepG2 or HepG2.2.15 in vitro and HSCs cultured alone served as the control.The mRNA expression of matrix metalloproteinase(MMP)-2 and tissue inhibitor of metalloproteinase(TIMP)-1 was detected by realtime PCR.The protein expression of MMP-2 and TIMp-1 was detected by Western-blot.Results Compared with the control and the HSCs co-cultured with HepG2,the expression of MMP-2 and TIMP-1 mRNA in HSCs co-cultured with HepG2.2.15 was increased remarkably and the most significant difference was found at 72 h(F=11.91,23.13;P=0.008,0.001);the expression of MMP-2 and TIMP-1 protein in HSCs co-cuhured with HepG2.2.15 was also increased remarkably and the most significant difference was found at 72 h(F=20.70,6.54;P=0.002,0.003)too.Conclusion The expression of fibrosis-related factors in HSCs increased significantly after co-cultured with HepG2.2.15,which suggests that HBV could promote liver fibrosis.

Hypoxia is a general characteristic of most solid malignancies and intimately related to cancer progression. Homeostatic response to hypoxia is primarily mediated by hypoxia inducible factor-1alpha (HIF-1alpha) that elicits transcriptional activity through recruitment P300 coactivator. Targeting the interaction of HIF- alpha and P300 would thus constitute a novel approach for cancer treatment by suppressing tumor angiogenesis and metastasis. Here, a screening assay was developed for inhibitors targeting the interaction between HIF-1alpha and P300. The nucleotide sequence of human HIF-1alpha and P300 were cloned into pBIND and pACT vectors, named pBIND-HIF1alpha and pACT-P300. The interaction of HIF-1alpha and P300 was identified in HEK293 cell using mammalian two-hybrid system. And compound chetomin decreased their interaction in this mammalian two-hybrid system. We further verified HIF-1 inhibition effect of chetomin in U251-HRE cells. Therefore, we established a screening assay combined HIF-1alpha and P300 mammalian two-hybrid system and U251-HRE reporter assay for HIF-1 selective inhibitors.
Cell Hypoxia ; Disulfides ; pharmacology ; Drug Screening Assays, Antitumor ; E1A-Associated p300 Protein ; antagonists & inhibitors ; HEK293 Cells ; Humans ; Hypoxia-Inducible Factor 1, alpha Subunit ; antagonists & inhibitors ; Indole Alkaloids ; pharmacology ; Two-Hybrid System Techniques

Hypoxia-inducible factor-1 (HIF-1) is a key transcription factor on hypoxia responses in mammalian tissues. HIF-1 plays as a positive factor in solid tumor and leads to hypoxia-driven responses that enhance its downstream gene expression for tumor growth and survival. LXY6099 was obtained by the structural modification and optimization of manassantin A (MA) as a high potent HIF-1 inhibitor. Antitumor activity of LXY6099 was observed in this study. LXY6099 with an IC50 value of 2.46 x 10(-10) mol x L(-1) showed more sensitive inhibition activity to HIF-1 than that of MA detected by reporter gene assay (> 100 folds). It showed strong inhibition on the growth of human solid tumor cell lines. Furthermore, LXY6099 exhibited significant antitumor activity against established human tumor xenografts in nu/nu mice with treatment of MX-1 breast cancer. Thus, LXY6099 as a novel HIF-1 inhibitor could be further developed into anti-cancer agents.
Animals ; Antineoplastic Agents ; pharmacology ; Breast Neoplasms ; metabolism ; Cell Line, Tumor ; Gene Expression Regulation, Neoplastic ; Heterografts ; Humans ; Hypoxia-Inducible Factor 1 ; metabolism ; Lignans ; pharmacology ; Mice, Nude

Hypoxia-inducible factor-1 (HIF-1) is a key transcription factor on hypoxia responses in mammalian tissues. HIF-1 plays as a positive factor in solid tumor and leads to hypoxia-driven responses that enhance its downstream gene expression for tumor growth and survival. LXY6099 was obtained by the structural modification and optimization of manassantin A (MA) as a high potent HIF-1 inhibitor. Antitumor activity of LXY6099 was observed in this study. LXY6099 with an IC50 value of 2.46 x 10(-10) mol x L(-1) showed more sensitive inhibition activity to HIF-1 than that of MA detected by reporter gene assay (> 100 folds). It showed strong inhibition on the growth of human solid tumor cell lines. Furthermore, LXY6099 exhibited significant antitumor activity against established human tumor xenografts in nu/nu mice with treatment of MX-1 breast cancer. Thus, LXY6099 as a novel HIF-1 inhibitor could be further developed into anti-cancer agents.