Study of the effect of PU-H71 on increasing radiosensitivity of cervical cancer cells / 中华放射肿瘤学杂志

Objective:To investigate the effect of heat shock protein 90 (Hsp90) inhibitor PU-H71 combined with X-ray on radioresistant human cervical cancer cells.Methods:The expression levels of Hsp90 gene between cervical cancer tissues and adjacent tissues were analyzed by bioinformatics. Radioresistant cervical cancer cell lines HeLa RR and SiHa RR were obtained by fractional irradiations (2 Gy per fraction, 30 fractions). The cell lines were divided into the control group (treated with dimethyl sulfoxide), irradiation alone group, PU-H71 group (treated with 0.5 μmol/L PU-H71), and PU-H71+irradiation group (irradiation at 24 h after treatment with 0.5 μmol/L PU-H71). Cell survival was detected by clonal formation assay. Immunofluorescence assay was used to detect γH2AX foci at 1, 6, and 24 h after cell treatment. The expression level of Rad51 protein at 1, 2, 6, 12, and 24 h after cell treatment was detected using Western blot. The expression level of phosphorylated DNA-dependent protein kinase catalytic subunit (p-DNA-PKcs) was measured at 2 h after cell treatment. Cell apoptosis at 48 h after cell treatment was assessed by flow cytometry. Results:PU-H71 enhanced the sensitivity of radioresistant cervical cancer cells to X-ray. Compared with the irradiation alone group, the radiation sensitization ratios (SER) of HeLa RR and SiHa RR cells at 10% survival were 1.36 and 1.27, and the apoptosis rates were increased by approximately 72.1% and 63.1% in the PU-H71+irradiation group, respectively. PU-H71 delayed the duration of γH2AX foci induced by X-ray, inhibited the phosphorylation of DNA-dependent protein kinase catalytic subunit (DNA-PKcs), thus preventing non-homologous end joining (NHEJ) repair and delaying homologous recombination repair.Conclusion:PU-H71 increases the radiosensitivity of radioresistant cervical cancer cells by inhibiting the repair pathway of DNA double-strand break, which is expected to be a radiosensitizer to enhance the efficacy of radiotherapy for cervical cancer.

Synergistic effect of Hsp90 inhibitor ginkgolic acids C15 ꞉1 combined with paclitaxel on nasopharyngeal carcinoma / 中南大学学报(医学版)

OBJECTIVES@#Nasopharyngeal cracinoma is a kind of head and neck malignant tumor with high incidence and high mortality. Due to the characteristics of local recurrence, distant metastasis, and drug resistance, the survival rate of patients after treatment is not high. Paclitaxel (PTX) is used as a chemotherapy drug in treating nasopharyngeal carcinoma, but nasopharyngeal carcinoma cells are easy to develop resistance to PTX. Inhibition of heat shock protein 90 (Hsp90) can overcome common signal redundancy and resistance in many cancers. This study aims to investigate the anti-tumor effect of ginkgolic acids C15꞉1 (C15:1) combined with PTX on nasopharyngeal carcinoma CNE-2Z cells and the mechanisms.@*METHODS@#This experiment was divided into a control group (without drug), a C15:1 group (10, 30, 50, 70 μmol/L), a PTX group (5, 10, 20, 40 nmol/L), and a combination group. CNE-2Z cells were treated with the corresponding drugs in each group. The proliferation of CNE-2Z cells was evaluated by methyl thiazolyl tetrazolium (MTT). Wound-healing assay and transwell chamber assay were used to determine the migration of CNE-2Z cells. Transwell chamber was applied to the impact of CNE-2Z cell invasion. Annexin V-FITC/PI staining was used to observe the effect on apoptosis of CNE-2Z cells. The changes of proteins involved in cell invasion, migration, and apoptosis after the combination of C15꞉1 and PTX treatment were analyzed by Western blotting.@*RESULTS@#Compared with the control group, the C15꞉1 group and the PTX group could inhibit the proliferation of CNE-2Z cells (all P<0.05). The cell survival rates of the C15꞉1 50 μmol/L combined with 5, 10, 20, or 40 nmol/L PTX group were lower than those of the single PTX group (all P<0.05), the combination index (CI) value was less than 1, suggesting that the combined treatment group had a synergistic effect. Compared with the 50 μmol/L C15꞉1 group and the 10 nmol/L PTX group, the combination group significantly inhibited the invasion and migration of CNE-2Z cells (all P<0.05). The results of Western blotting demonstrated that the combination group could significantly down-regulate Hsp90 client protein matrix metalloproteinase (MMP)-2 and MMP-9. The results of double staining showed that compared with the 50 μmol/L C15꞉1 group and the 10 nmol/L PTX group, the apoptosis ratio of CNE-2Z cells in the combination group was higher (both P<0.05). The results of Western blotting suggested that the combination group could decrease the Hsp90 client proteins [Akt and B-cell lymphoma-2 (Bcl-2)] and increase the Bcl-2-associated X protein (Bax).@*CONCLUSIONS@#The combination of C15꞉1 and PTX has a synergistic effect which can inhibit cell proliferation, invasion, and migration, and induce cell apoptosis. This effect may be related to the inhibition of Hsp90 activity by C15꞉1.

Research progress of heat shock protein 90 in breast cancer / 中华内分泌外科杂志

Breast cancer has become the most common malignant tumor in the world. Heat shock protein 90 (HSP90) is a kind of molecular chaperone which can promote protein folding and maintain protein stability. HSP90 includes HSP90α, HSP90β, GRP94 and TRAP1 subtypes. Previous studies have found that the level of HSP90 is significantly increased in malignant tumors such as breast cancer, and is closely related to the occurrence and development of tumors. Meanwhile, the research on inhibitors targeting HSP90 has also attracted much attention. In this paper, we reviewed the expression of four HSP90 subtypes in breast cancer and their relationship with the clinicopathologic feature and prognosis of patients, discussed the research progress of specific inhibitors of HSP90 subtypes in breast cancer, and analyzed the application prospect of HSP90 as biomarkers for breast cancer prognosis monitoring and therapeutic targets.

The Relationship between PPP2R5C and Molt-4 Cell Viability, HSP90-GR Signal in Childhood Acute T Lymphocytic Leukemia / 中国实验血液学杂志

OBJECTIVE@#To investigate the effect of PPP2R5C to the activity of Molt-4 cells in childhood acute T lymphocytic leukemia and its mechanism.@*METHODS@#The small interfering RNA (siRNA) technology targeting PPP2R5C gene was used to down-regulate the expression of PPP2R5C in Molt-4 cells. At the same time, a blank control group, a negative control group and a 17-DMAG group were set up. The cells in the negative control group were transfected with siRNA-NC, the cells in 17-DMAG group were treated with the HSP90 inhibitor 17-DMAG at a final concentration of 6.4 μmol/L for 48 h. Real-time fluorescent quantitative PCR (RT-qPCR) and Western blot were used to detect transfection efficiency; CCK-8 method was used to detect the proliferation activity of the cells in each group, EdU was used to detect the proliferation level of the cells in each group, flow cytometry was used to detect the cell cycle distribution ratio of the cells in each group, Annexin V-FITC/PI staining was used to detect the apoptosis of the cell, RT-qPCR and Western blot were used to detect the expression changes of heat shock protein 90 (HSP90) and glucocorticoid receptor (GR) of the cells in each group.@*RESULTS@#After Molt-4 cells were transfected with siRNA-PPP2R5C, the expression of PPP2R5C mRNA and protein in the cells were down-regulated significantly compared with those in the blank control group and the si-NC group (P<0.05); compared with cells in the blank control group and the si-NC group, the proliferation activity of the cells in the siRNA-PPP2R5C group and the 17-DMAG group significantly decreased (P<0.05), and the rate of EdU positive cells was significantly reduced (P<0.05); the proportion of the cells in G1 phase decreased while the proportion of the cells in G2 phase increased (P<0.05), the apoptosis rate of the cells also increased significantly (P<0.05); in addition, the expression of PPP2R5C mRNA and protein of the cells in siRNA-PPP2R5C group was significantly down-regulated compared with those in the blank control group and si-NC group (P<0.05). The expressions of PPP2R5C mRNA and protein in the 17-DMAG group were also significantly down-regulated compared with those in the blank control group and si-NC group (P<0.05).@*CONCLUSION@#Down-regulation of PPP2R5C gene expression can inhibit Molt-4 cell activity in childhood acute T lymphocytic leukemia, block the cells in G2 phase, and promote cell apoptosis, the mechanism may be related to the inhibition of HSP90-GR signaling pathway.

HSP90α exacerbates house dust mite-induced asthmatic airway inflammation by upregulating endoplasmic reticulum stress in bronchial epithelial cells / 南方医科大学学报

OBJECTIVE@#To explore the role of heat shock protein 90α (HSP90α) and endoplasmic reticulum (ER) stress pathway in allergic airway inflammation induced by house dust mite (HDM) in bronchial epithelial cells.@*METHODS@#A HDM- induced asthmatic cell model was established in human bronchial epithelial (HBE) cells by exposure to a concentration gradient (200, 400 and 800 U/mL) of HDM for 24 h. To test the effect of siHSP90α and HSP90 inhibitor 17-AAG on HDM-induced asthmatic inflammation, HBE cells were transfected with siHSP90α (50 nmol, 12 h) or pretreated with 17-AAG (900 nmol, 6 h) prior to HDM exposure (800 U/mL) for 24 h, and the changes in the expression of HSP90α and ER stress markers were assessed. We also tested the effect of nasal drip of 17-AAG, HDM, or their combination on airway inflammation and ER stress in C57BL/6 mice.@*RESULTS@#In HBE cells, HDM exposure significantly up-regulated the expression of HSP90α protein (P=0.011) and ER stress markers XBP-1 (P=0.044), ATF-6α (P=0.030) and GRP-78 (P=0.027). Knocking down HSP90α and treatment with 17-AAG both significantly inhibited HDM-induced upregulation of XBP-1 (P=0.008). In C57BL/6 mice, treatment with 17-AAG obviously improved HDM-induced airway inflammation and significantly reduced the number of inflammatory cells in the airway (P=0.014) and lowered the levels of IL-4 (P=0.030) and IL-5 (P=0.035) in alveolar lavage fluid. Immunohistochemical staining showed that the expressions of XBP-1 and GRP-78 in airway epithelial cells decreased significantly after the treatment of 17-AAG.@*CONCLUSIONS@#HSP90α promotes HDM-induced airway allergic inflammation possibly by upregulating ER stress pathway in bronchial epithelial cells.

Clinical significance of heat shock protein 90 expression in patients with lung adenocarcinoma / 中国医师杂志

Objective:To investigate the expression of heat shock protein 90 (HSP90) and the relationship between the expression of HSP90 and the clinicopathological features or prognosis in patients with lung adenocarcinoma (ADC).Methods:The paraffin specimens of 193 patients with lung adenocarcinoma and 53 non cancerous lung tissues (bullae and bronchiectasis) resected in Xiangya Second Hospital of Central South University were analyzed retrospectively. The expression of HSP90 in the tissue chip was detected by immunohistochemical streptavidin-perosidase (SP) method by high-throughput tissue chip, and the relationship between its expression level and the clinicopathological characteristics of patients was analyzed; Kaplan Meier survival curve was used to analyze the difference between different expression levels of HSP90 and the overall survival time of patients with lung adenocarcinoma.Results:The positive expression of HSP90 in lung adenocarcinoma was significantly higher than that in non cancerous lung tissue ( P<0.001), the expression level of HSP90 in clinical stage Ⅲ patients was higher than that in clinical stage Ⅰ-Ⅱ patients ( P=0.008), and the expression level of HSP90 in patients with lymph node metastasis was higher than that in patients without lymph node metastasis ( P=0.024); The 10-year survival rate of lung adenocarcinoma patients with high expression of HSP90 was significantly lower than that of patients with low expression of HSP90 ( P=0.001). The 10-year survival rate of lung ADC patients with stage Ⅲ and lymph node metastasis was significantly lower than that of patients with stage Ⅰ-Ⅱ and no lymph node metastasis ( P<0.05). Multiple Cox proportional hazard regression analysis further identified that lung ADC patients with overexpression of HSP90 had a poor prognosis ( P=0.010). Conclusions:HSP90 might play an important part in the development and progression of lung ADC and might act as a novel prognostic marker for patients with lung ADC.

The molecular mechanism of the effect of benzoαpyrene on autophagy of molecular chaperones under simulated hypoxia / 药学学报

In this study, the effect of benzo[α]pyrene (BaP) on chaperone-mediated autophagy (CMA) in a simulated hypoxia environment was observed and the relationship to heat shock protein 90 (HSP90) was clarified. With HSP90 inhibitor geldanamycin (GA) and HSP90α silenced, the mRNA and protein expression of hypoxia-inducible factor-1α (HIF-1α), HSP90, heat shock cognate protein 70 (HSC70), and lysosomal associated protein 2A (LAMP-2A) of A549 cells on hypoxic environment by BaP were tested. Alkaline comet experiment, immunofluorescence γ-H2AX focus experiment, quantitative real-time PCR (qPCR), and Western blot analyses were used to clarify the relationship between the DNA damage of different concentrations of BaP in A549 cells and the mRNA and protein expression of CMA-related factors. The results show that hypoxia can promote the expression of mRNA and protein of CMA-related factors in A549 cells. This study found that BaP has an inhibitory effect on CMA under the hypoxic environment. The inhibition or silencing of HSP90 will enhance the inhibitory effect of BaP on CMA. In a normoxic environment, BaP causes DNA damage and promotes CMA.

The "target + activity" method for rapid discovery of active compounds targeting Hsp90 in pancreatic cancer cells from Physalis angulata L / 药学学报

The purpose of this study was to select the active compounds targeting Hsp90 protein in pancreatic cancer cells through a new dual "target + activity" rapid discovery technique. We combined an in vitro anti-cancer activity screening method with a dual-luciferase reporter gene and multi-chromatography separation technology, for rapid discovery of potential Hsp90 inhibitors from the Chinese herbal medicine Physalis angulata L. The anti-proliferation activity of those compounds was assessed in pancreatic cancer cell line BxPC-3 by MTT assays. The molecular mechanisms of Hsp90 inhibition were explored by Western blot and shRNA knockdown assays. As a result, two withanolides, withanolide E (WE) and 4β-hydroxywithanolide E (HWE), were identified from Physalis angulata L. The half maximal inhibitory concentration (IC50) of WE and HWE were 0.71±0.03 and 1.23±0.10 μmol·L-1 for the growth of BxPC-3 cells in 48 h. Luciferase reporter assay demonstrated that WE and HWE significantly induced heat shock element (HSE) activity in a dose- and time-dependent manner. The molecular mechanism study showed that after exposing to 5 μmol·L-1 WE or HWE for 48 h, the aggregation of Hsp90 dimer was upregulated to 6.5±1.3 and 11.8±2.0 fold, while the expression of Hsp90 client protein Akt was downregulated to 21.7%±2.8% and 9.8%±1.4% of the control group. Moreover, the Hsp90 inhibitory activity of WE or HWE was canceled by shRNA mediated Hsp90 knockdown. Overall, based on the dual "target + active" rapid discovery technique, two new Hsp90 inhibitors WE and HWE were found from Physalis angulata L. The Hsp90 inhibitory mechanism of WE and HWE may be mediated by induction of Hsp90 aggregate dimer and inhibition of Hsp90 client protein Akt expression.

Clinical value of heat shock protein-90α on diagnosis, prediction of treatment response, and monitoring of relapse in breast cancer / 中国肿瘤临床

To explore the prognostic value of heat shock protein-90α (HSP-90α) plasma levels on breast cancer and non-breast malignant tumors, monitoring the response of chemotherapy, and the predictive value of cancer recurrence and metastasis. Methods: A total of 615 female patients were enrolled between June 2016 and September 2016 in Cancer Hospital, Chinese Academy of Medical Sciences, who were divided into the examination (n=389) and control (n=216) groups. The former group consisted of static (n=289) and dynamic (n=110) groups, which were analyzed by stages, histological and molecular type, and so on. The latter group in-cluded healthy people (n=103), and those with breast benign tumors (n=51) and non-breast malignant tumors (n=62). In all the plasma samples, HSP-90α was detected using a double-antibody enzyme-linked immunosorbent assay. The receiving-operating characteristic curve was used to analyze the effectiveness of plasma HSP-90α in the diagnosis of breast cancer. Wilcoxon＇s rank test and the Kruskal-Wallis test were used to analyze the association between clinical characteristics and levels of plasma HSP-90α. Results: The levels of plasma HSP-90α were significantly higher in patients with breast cancer than in healthy controls (P<0.001). When the cut-off value was set as 59.7 ng/mL for the diagnosis of breast cancer and 43.22 ng/mL for disease recurrence, the areas under the curve were 0.834 and 0.877, sensitivities were 90.3% and 95.7%, and specificities were 78.6% and 74.5%, respectively. The levels of plasma HSP-90α sig-nificantly decreased after achieving a response to neoadjuvant chemotherapy or surgery (P<0.05). Conclusions: Plasma HSP-90α has good clinical value in the diagnosis and monitoring of response and recurrence in breast cancer.

Expression of EGFR, HSP90A and Cathepsin D in nasopharyngeal carcinoma and their relationship with tumor invasion and metastasis / 重庆医学

Objective To investigate the expressions of epidermal growth factor receptor (EGFR),heat shock protein 90A (HSP90A) and cathepsin D in nasopharyngeal carcinoma and their relationship with tumor invasion and metastasis.Methods From January 2014 to December 2015,58 patients with nasopharyngeal carcinoma (group A) in the First Affiliated Hospital of University of South China were selected,and the positive expression rates of EGFR,HSP90A and cathepsin D in biopsy specimens of nasopharyngeal carcinoma were detected by immunohistochemistry method.The positive expression rates of EGFR,HSP90A and cathepsin D in biopsy chronic rhinitis tissues of 30 patients with chronic rhinitis (group B) were also detected.T staging,N staging and lymphatic vessel density (LVD) of patients in group A were analyzed.In group A,the T staging,N staging and LVD of between patients with positive expression of EGFR,HSP90A and eathepsin D and those with negative expression of these indicators were compared,and the correlations of the expression of EGFR,HSP90A and cathepsin D to T staging,N staging and LVD were analyzed.Results The positive expression rates of EGFR,HSP90A and cathepsin D in group A were 86.21％,82.76％ and 87.93％ respectively,which were higher than 30.00％,26.67％ and 33.33％ in group B (P＜0.05).In group A,the percentages of patients on T3-T4 and N2-N3 stages and LVD of patients with positive expression of EGFR,HSP90A and cathepsin D protein respectively were higher than those of patients with negative expression of corresponding protein (P ＜ 0.05).Spearman correlation analysis showed that the positive expression rates of EGFR,HSP90A and cathepsin D in nasopharyngeal carcinoma were positively correlated with the T staging,N staging and LVD (EGFR:r=0.844,0.795,0.785;HSP90A:r=0.862,0.825,0.822;eathepsin D:r=0.842,0.815,0.863,P＜0.05).Conclusion EGFR,HSP90A and cathepsin D expression in nasopharyngeal carcinoma are closely related to invasion and metastasis of tumor,which may be used as reference indexes for the evaluation of tumor invasion and metastasis in nasopharyngeal carcinoma.

Progress in Molecular Chaperone Regulation of Heat Shock Protein 90 and Cancer / 分析化学

Heat shock protein 90 (HSP90) is a member of genetically conserved heat shock protein family. As an important molecular chaperone in eukaryotic cells, HSP90 plays a key regulatory role in maintaining cellular protein homeostasis. HSP90 clients encompass a wide range of proteins, thus HSP90 is involved in diverse biological process. With the deeper study, it is found that HSP90 takes an important part in the development and metastasis of cancer,and has become a promising target for the study of anticancer biology. We review the progress of HSP90 as molecular chaperone and its relationship with cancer.

Antiviral and Anti-Inflammatory Activities of Pochonin D, a Heat Shock Protein 90 Inhibitor, against Rhinovirus Infection

Human rhinoviruses (HRV) are one of the major causes of common cold in humans and are also associated with acute asthma and bronchial illness. Heat-shock protein 90 (Hsp90), a molecular chaperone, is an important host factor for the replication of single-strand RNA viruses. In the current study, we examined the effect of the Hsp90 inhibitor pochonin D, in vitro and in vivo, using a murine model of human rhinovirus type 1B (HRV1B) infection. Our data suggested that Hsp90 inhibition significantly reduced the inflammatory cytokine production and lung damage caused by HRV1B infection. The viral titer was significantly lowered in HRV1B-infected lungs and in Hela cells upon treatment with pochonin D. Infiltration of innate immune cells including granulocytes and monocytes was also reduced in the bronchoalveolar lavage (BAL) by pochonin D treatment after HRV1B infection. Histological analysis of the lung and respiratory tract showed that pochonin D protected the mice from HRV1B infection. Collectively, our results suggest that the Hsp90 inhibitor, pochonin D, could be an attractive antiviral therapeutic for treating HRV infection.

Plasma HSP90 Alpha Testing Clinical Application Value in the Diagnosis of Lung Cancer Researc / 现代检验医学杂志

Objective To study the plasma heat shock protein 90 alpha (HSP90 α) in the diagnosis of lung cancer.Methods Chose 166 cases of patients with lung cancer,lung cancer group,the same physical examination of 20 cases of normal (control group),application of plasma concentration of HSP90 α enzyme-linked immunoassay detection,chemiluminescence detection of CEA,NSE,SCC and CYFRA21-1,of the two groups of data by t test statistical analysis,compared two groups of plasma HSP90 α level.With plasma HSP90 alpha was greater than 86 ng/ml for the critical value,calculation of HSP90 α testing sensitivity.Patients with lung cancer by histopathologic classification,compare different tumor classification in patients with plasma HSP90 α level.Used Pearman's correlation method to analyse the relationship of HSP90 α,CEA and NSE in patients with lung cancer,between SCC and CYFRA21-1 and used ROC curve to evaluate HSP90 α efficiency to the diagnosis of lung cancer.Results ① In lung cancer group and control group in the indicators HSP90 α,CEA,NSE,SCC and respectively CYFRA21-1 190.33±105.86 vs 41.02±19.73 ng/ml,8.68±5.02 vs 4.02±1.36 ng/ml,36.32±13.16 vs 8.32 ±3.96 ng/ml,6.21±1.62 vs 1.23±0.64 ng/ml,10.63±4.33 vs 3.02±1.66 ng/ml.Compared with control group (t=10.48,8.66,12.36,9.52,15.36,P＜0.01),the difference was statistically significant.② For biological reference range (HSP90 α:0～86 ng/ml,CEA 1.0～5 ng/ml,NSE:1.0～17.5 ng/ml,SCC:0.2～1.6 ng/ml,CYFRA21-1:1.0～2.6 ng/ ml) as the standard in lung cancer group,HSP90 α increased 73.49 ％,CEA increased 19.27 ％,NSE increased 19.27 ％,CYFRA21-1 (21.68％) and SCC increased 29.51％.③ Patients with lung cancer by histopathologic classification,different concentration of tumor classification HSP90 α was no difference (P＞0.05).④Spearman rank correlation analysis showed that HSP90 α levels were positively correlated with CYFRA21-1 (r,=0.44,P＜0.01).The difference was statistically significant (F=14.98,P =0.00).HSP90 α and CEA,NSE,SCC had no relevance.⑤ HSP90 α and CEA,NSE,SCC,CYFRA21-1 the area under the ROC curve (AUC) in the diagnosis of lung cancer were:0.961,0.562,0.731,0.465 and 0.632 best cutoff value were 89.3 ng/ml,6.32 ng/ml,18.63 ng/ml,1.93 ng/ml and 2.36 ng/ml.Sensitivity of 73.49％,52.3％,73.49％,59.6％ and 62.1％,specific degrees respectively.Accuracy of 98.6％,46.3％,66.3％,98.6％ and 46.3％,respectively,88.4％,80.3％,86.9％,87.2％ and 89.2％ of the five joint,the sensitivity of diagnosis of lung cancer and specific degrees respectively 100％ and 75％.Conclusion Using ROC curve analysis showed that HSP90 α plays an auxiliary role in diagnosis of lung cancer,CEA,NSE,CYFRA21-1 and SCC can significantly increase the detection rate of lung cancer.

Establishment of quantitative fluorescence immunochromatographic assay detection method for heat shock protein 90α(HSP90α) / 中国免疫学杂志

Objective:To establish quantitative a fluorescence immunochromatographic assay detection method for the heat shock protein 90α(HSP90α)in human serum.Methods: Indirect the technology of fluorescence microshers immunochromatographic assay was used to research fluorescent microsphere activation,ensure optimal testing time,determine linearity range,precision,recovery experiments,testing clinical samples and that sort of thing in the fluorescence immunochromatographicassay experiment.Results: In all the reaction conditions,it was determined that the optimal teaction time was 5 minutes,and in the best line range (0.39-100 ng/ml) precision quality control materials of high recovery (30 ng/ml) Intra-assay CV was 8.14%;quality control materials of low recovery (10 ng/ml) Intra-assay CV was 9.26%.With high,medium and low recovery of serum recovery was 100.56%,99.76%,94.1%,separately.Foreign kit(ELISA) for detection of 40 cancer patients clinical serum,the result showed that the correlation was 0.968 5.Conclusion: Establishing the method initially quantitative fluorescence immunochromatographic assay for the heat shock protein 90α(HSP90α)in human serum have high performance and linear,clinic accordance rate also can satisfy the demand of clinic quantitative detection,and will improve hopeful to applied to clinic after apprroved.

HTRF-based method for determination of HSP90-HOP inhibition activity and its application / 药学学报

HSP90 is widely expressed in cells with the main function in assisting the maturation of other proteins that are called clients. Many clients play critical roles in the occurrence and development of cancer. Inhibition of HSP90 can lead to degradation of the oncogenic proteins, and result in potent anti-cancer effects. HSP90-HOP interaction is critical for the chaperone function of HSP90, thereby disruption of the HSP90-HOP interaction is a novel strategy in the inhibition of HSP90. Based on the technology of homogeneous time-resolved fluorescence (HTRF), we developed a new assay for the identification of new inhibitors of HSP90-HOP interaction. This method was evaluated in the study of the HSP90-HOP inhibition activity of the pentapeptide MEEVD from HSP90 C-terminal and its derivatives. This study can provide a basis for the screening and discovery of novel HSP90-HOP disruptors.

Co-chaperones: regulated action in conformational functions of HSP90 and their actions in cancer / 药学学报

Heat shock protein 90(HSP90), as an essential molecular chaperone, regulates the folding, assembly and maturation of a wide range of oncogenic client proteins. The process of adenosine triphosphate(ATP)binding and adenosine diphosphate(ADP)/ATP exchange act as a conformational switch to regulate the chaperone function of HSP90. Furthermore, this process is controlled by a range of accessory proteins(as referred to co-chaperones), such as Hop, CDC37, p23, AHA1, PP5, etc. This article describes the structure and function of several co-chaperones, and their roles in tumor progress.

Proposal of Dual Inhibitor Targeting ATPase Domains of Topoisomerase II and Heat Shock Protein 90

There is a conserved ATPase domain in topoisomerase II (topo II) and heat shock protein 90 (Hsp90) which belong to the GHKL (gyrase, Hsp90, histidine kinase, and MutL) family. The inhibitors that target each of topo II and Hsp90 are intensively studied as anti-cancer drugs since they play very important roles in cell proliferation and survival. Therefore the development of dual targeting anti-cancer drugs for topo II and Hsp90 is suggested to be a promising area. The topo II and Hsp90 inhibitors, known to bind to their ATP binding site, were searched. All the inhibitors investigated were docked to both topo II and Hsp90. Four candidate compounds as possible dual inhibitors were selected by analyzing the molecular docking study. The pharmacophore model of dual inhibitors for topo II and Hsp90 were generated and the design of novel dual inhibitor was proposed.

Small Molecule Inhibitors to Disrupt Protein-protein Interactions of Heat Shock Protein 90 Chaperone Machinery

Heat shock protein 90 (Hsp90) is an adenosine triphosphate dependent molecular chaperone in eukaryotic cells that regulates the activation and maintenance of numerous regulatory and signaling proteins including epidermal growth factor receptor, human epidermal growth factor receptor 2, mesenchymal-epithelial transition factor, cyclin-dependent kinase-4, protein kinase B, hypoxia-inducible factor 1alpha, and matrix metalloproteinase-2. Since many of Hsp90 clients are oncogenic proteins, Hsp90 has become an attractive therapeutic target for treatment of cancer. To discover small molecule inhibitors targeting Hsp90 chaperone machinery, several strategies have been employed, which results in three classes of inhibitors such as N-terminal inhibitors, C-terminal inhibitors, and inhibitors disrupting protein-protein interactions of Hsp90 chaperone machinery. Developing small molecule inhibitors that modulate protein-protein interactions of Hsp90 is a challenging task, although it offers many alternative opportunities for therapeutic intervention. The lack of well-defined binding pocket and starting points for drug design challenges medicinal chemists to discover small molecule inhibitors disrupting protein-protein interactions of Hsp90. The present review will focus on the current studies on small molecule inhibitors disrupting protein-protein interactions of Hsp90 chaperone machinery, provide biological background on the structure, function and mechanism of Hsp90's protein-protein interactions, and discuss the challenges and promise of its small molecule modulations.

Potential Prognostic Value of Histone Deacetylase 6 and Acetylated Heat-Shock Protein 90 in Early-Stage Breast Cancer / 한국유방암학회지

PURPOSE: Histone deacetylase 6 (HDAC6) is an enzyme that deacetylates heat-shock protein 90 (HSP90). Many studies have investigated the role of HDAC6 and HSP90 in tumorigenesis and in the prognosis of cancer patients. This study aimed to evaluate the prognostic value of HDAC6 and acetylated HSP90 (acetyl-HSP90) in a cohort of breast cancer patients. METHODS: Immunohistochemical analysis of 314 surgical specimens obtained from patients with invasive breast cancer was carried out to assess standard pathologic factors and the expression of HDAC6 and acetyl-HSP90. Statistical analyses were performed to determine the association between HDAC6, acetyl-HSP90, and conventional clinicopathological factors, and the prognostic values of these factors were evaluated. RESULTS: HDAC6 expression did not show any correlation with other clinicopathological factors, but acetyl-HSP90 was significantly correlated with histologic grade (p=0.001) and the Ki-67 index (p=0.015). HDAC6 and acetyl-HSP90 expression were significantly associated with each other (p=0.047). Although HDAC6 was not prognostic for disease-free survival (DFS), some patients with high expression of HDAC6 experienced recurrence 5 years after diagnosis, while there was no recurrent disease after 5 years in those with low expression. Acetyl-HSP90 was significantly associated with the DFS of all patients (p=0.016) and with high HDAC6 expression (p=0.017), but not with low expression. CONCLUSION: Expression of HDAC6 and acetyl-HSP90 are correlated. HDAC6 is proposed to be a possible predictive marker of late recurrence, and acetyl-HSP90 has prognostic value in predicting the DFS of breast cancer patients.

Histone deacetylase inhibitor LBH589 induces apoptosis of multiple myeloma cell line U266 in vitro and its mechanism / 白血病·淋巴瘤

Objective To study the effect of new generation histone deacetylase inhibitor LBH589 single-drug or combined with the mouse serum which contains the radix echinopsis on multiple myeloma (MM) cell line U266 and their mechanism.Methods The acetylation level of α-tublin which was a substrate of HDAC6 was detected by Western blot.The chemical force between Heat shock protein 90 (HSP90) and its client proteins was detected by immune precipitation (IP).Results The different concentrations of LBH589 single drug (0,20,50 nmol/L),and 50 nmol/L combined with the mouse serum which contained the radix echinopsis (1 g/ml) were able to inhibit the proliferation of U266 cell.With the increase of drug concentration and the extension of time,the acetylation levels of α-tublin and HSP90 increased gradually (at 24 or 48 hours) in a dose dependent (P ＜ 0.05).The inhibition of LBH589 combined with the mouse serum was stronger than that of LBH589 single drug (P ＜ 0.05).Conclusion LBH589 could inhibit the growth of MM cells and their cell cycles,and induce the apoptosis of MM cell line U266.