Expression of MDR1, HIF-1α and MRP1 in sacral chordoma and chordoma cell line CM-319

Background

Chordoma was a typically slow-growing tumor. The therapeutic approach to chordoma had traditionally relied mainly on surgical therapy. And the main reason for therapeutic failure was resistance to chemotherapy and radiotherapy. However the refractory mechanism was not clear. The aim of this study was to investigate the expression of three genes (MDR1, HIF-1α and MRP1) associated with resistance to chemotherapy and radiotherapy in chordoma and chordoma cell line CM-319.

Materials and methods

Using immunohistochemical techniques, the expression of MDR1, HIF-1α and MRP1 was investigated in 50 chordoma specimen. Using RT-PCR and Western blot, the expression of MDR1, HIF-1α and MRP1 was investigated in chordoma and chordoma cell line CM-319.

Results

Expression of MDR1, HIF-1α and MRP1 was observed in 10%, 80% and 74% of all cases, respectively. Expression of MRP1 was correlated with HIF-1α. On the other hand, expression of MDR1 was not correlated with the expression of HIF-1α or MRP1. The expression of HIF-1α and MRP1 was observed, but MDR1 was not observed in chordoma and CM-319.

Conclusion

Expression of HIF-1α and MRP1 was observed in most chordoma specimen and CM-319 cell line; expression of HIF-1α correlated with MRP1. HIF-1α and MRP1 may play a role in the multidrug resistance of chordoma to chemotherapy.     

Quantification of thrombospondin-1 secretion and expression of αvβ3 and α3β1 integrins and syndecan-1 as cell-surface receptors for thrombospondin-1 in malignant glioma cells

Malignant glioma cells secrete thrombospondin-1 (TSP-1) which participates in the motility of glioma cells, and binds to cell surface v3 and 31 integrins, and syndecan-1. This study evaluated the amount of TSP-1 secretion from malignant glioma cells, and the expression of v3 and 31 integrins, and syndecan-1. The amounts of TSP-1 in the supernatants from 10 malignant glioma cell lines and eight non-glioma malignant tumor cell lines were measured by enzyme-linked immunosorbent assay. Expression of v3 and 31 integrins, and syndecan-1 were examined by flow cytometry. The amounts of TSP-1 secreted by malignant glioma cells were 43 to 2431 ng/1 × 10⁶ cells/24 h (mean ± SD=626 ± 792). Seven of 10 glioma cell lines secreted more than 100 ng of TSP-1 and three of these cell lines secreted more than 1 g. Seven of eight non-glioma cell lines secreted less than 100 0ng of TSP-1. All glioma cell lines expressed 31 integrin and syndecan-1, and seven of 10 glioma cell lines expressed v3 integrin. Treatment of the glioma cell lines with TGF-2 did not change the expression of v3 integrin. These results suggest that malignant glioma cells secrete high levels of TSP-1, which may be important in the migration of glioma cells via interactions with v3 and 31 integrins, and syndecan-1.     

Syntaxins 3 and 4 mediate vesicular trafficking of α5β1 and α3β1 integrins and cancer cell migration

Integrins, a family of heterodimeric receptors for cell adhesion to the extracellular matrix (ECM), play key roles in cell migration, cancer progression and metastasis. As transmembrane proteins, integrins are transported in vesicles and delivered to the cell surface by vesicular trafficking. The final step for integrin delivery, i.e., fusion of integrin-containing vesicles with the plasma membrane, is poorly understood at the molecular level. The SNARE (soluble N-ethylmaleimide-sensitive factor attachment protein receptor) proteins syntaxins 1, 2, 3 and 4 are present at the plasma membrane to drive vesicle fusion. In this study, we examined the roles of syntaxins?1, 2, 3 and 4 in vesicular trafficking of α5β1 and α3β1 integrins. We showed that syntaxins?2, 3 and 4 were expressed in HeLa cervical adenocarcinoma cells and PANC-1 pancreatic adenocarcinoma cells. In migrating HeLa and PANC-1 cells, syntaxins?2, 3 and 4 co-localized with the lipid raft constituent GM1 ganglioside at the leading edge. siRNA knockdown (KD) of syntaxins?3 and 4, but not of syntaxin?2, in HeLa cells reduced cell surface expression of α5β1 and α3β1 integrins and accumulated the integrins in cytoplasmic vesicles, indicating that syntaxins?3 and 4 mediate vesicular trafficking of α5β1 and α3β1 integrins to the cell surface. In addition, KD of syntaxins?3 and 4 inhibited cell adhesion to fibronectin, suppressed chemotactic cell migration and triggered apoptosis. Collectively, these data suggest that syntaxins?3- and 4-dependent integrin trafficking is important in cancer cell migration and survival, and may be a valuable target for cancer therapy.     

Expression and Clinical Significance of HMGB1 and RAGE in Cervical Carcinoma

OBJECTIVE To study the expression level and clinical significance of HMGB1 and RAGE in cervical squamous epithelial carcinoma. METHODS Real time quantitative polymerase chain reaction(qRT-PCR) was employed to examine the expression of HMGB1(high mobility group box protein1),and RAGE(receptor for advanced glycation endproducts)in 60 cervical squamous epithelial carcinomas(CSEC),their paraneoplastic tissues(PS)and 30 normal cervix tissues(NCS). RESULTS The expression of HMGB1 in the CSEC samples and PS was similar(P>0.05),but higher compared to NCS(P<0.05).Overexpression of HMGB1 in the CESC tissues was significantly correlated with the tumor (P<0.05),and the presence of metastasis(P<0.01),but not correlated with the tumor diameter or tumor grade.RAGE expression was not significantly different among these tissue types,and showed no significant correlation with the the tumor stage,diameter or grade.But there was a significant positive correlation between RAGE expression and CSEC metastasis. CONCLUSION The results suggest that HMGB1 may be related to the proliferation,progression and metastasis of CSEC.The relationship of HMGB1/RAGE may be of importance for CSEC metastasis.HMGB1 presents a new potential gene target for prevention and treatment of CSEC. Study of HMGB1/RAGE expression will offer an experimental foundation for understanding the pathogenesis of CSES.     

Relationship between the Expression of VEGF, FIk-1 and Fit-1 Proteins and Clinicopcrthology in Hepatocellular Carcinoma

Objective To study the relationship between the expression of VEGF, Flk-1 and Flt-1 proteins and clinical pathology in hepatocellular carcinoma. Methods The expression of VEGF, Flk-1 and Flt-1 proteins in hepatocellular carcinomas from 60 patients was determined by immunohistochemistry (ABC method) and VEGF expression in relation to the clinicopathology evaluated. Results The positive rates of VEGF, Flk-1 and Flt-1 protein expression were 81.3%, 88.3%, 80.0% in tumor tissues, respectively, rates which were significantly higher than those in normal liver tissue (P<0.05). The expression of VEGF protein was correlated with the histologic grade and metastases of the tumors. Conclusion The results showed that, in hepatocellular carcinoma, a higher expression of VEGF protein was associated with a higher degree of malignancy and a greater tendency for metastases. VEGF, Flk-1 and Flt-1 play an important role in tumourgenesis. The project was funded by the Tianjin Natural Science Grant (No. 01361561).     

Genetic polymorphisms of metabolic enzymes—CYP1A1, CYP2D6, GSTM1, and GSTT1, and gastric carcinoma susceptibility

Genetic polymorphisms in metabolic enzymes are associated with numerous cancers. In this study, the relationships between genetic polymorphisms of phase I metabolic enzymes including cytochrome P450 1A1 (CYP1A1), CYP2D6 and phase II metabolic enzymes such as glutathione S-transferase M1 (GSTM1) and GSTT1 and gastric carcinoma susceptibility were investigated. Genomic DNA was isolated from the peripheral blood of 129 healthy controls and 123 gastric carcinoma patients from Han ethnic group of Hunan Province located in Central South China. The genetic polymorphisms of the above mentioned enzymes were analyzed using PCR-RFLP techniques. There was no significant difference among the frequencies of CYP1A1 and/or CYP2D6 gene’s wild type, heterozygous or homozygous mutations between the gastric carcinoma group and control group. But the differences among the frequencies of GSTM1 and GSTT1 null genotype between the gastric carcinoma and control group were significant (both P < 0.05). Also there were significant differences in the frequencies of GSTM1 null in high/high–middle differentiated, middle differentiated, middle–low differentiated and low differentiated gastric tumor separately. GSTM1 null showed an increased risk in middle–low differentiated and low differentiated gastric carcinoma type, but GSTT1 null was not a risk factor for the four pathological types of gastric carcinoma mentioned above. We report here that the genotypes of CYP1A1 and CYP2D6 are not associated with gastric carcinoma risk; GSTM1 null, but not GSTT1 null inheritably increases risk of some pathological types of gastric carcinoma in Han ethnic population of Hunan Province.     

Expression of TGF-β1 and the mechanism of invasiveness and metastasis induced by TGF-β1 in breast cancer

Objective To investigate the expression of MMP-2,TIMP-2,TGF-β1 and TGF-βRI and the relationship among them in breast cancer.Methods The protein expression of MMP-2,TIMP-2,TGF-β1 and TGF-β1R1 was detected on tissue chips by S-P immunohistochemical staining in 160 cases of breast carcinoma.Results The positive rates of TGF-β1,TGF-β1 mRNA,MMP-2,MMP-9,TIMP-1 and TIMP-2 expression were 73.7%,56.2%,96.9%,95.0%,87.5% and 89.4%,respectively.Axillary lymph node metastasis and TNM staging(P ＜0.01 and P ＜0.01,respectively)were positively correlated to the expression of TGF-β1.Relase-free survival of TGF-β1 positive group was lower than that of TGF-β1 negative group(P = 0.023).The expression of M MP-2 or M M P-9 was positively correlated to that of TGF-β1 (r=0.170,P＜0.05;r =0.221,P＜0.01)and was negatively correlated to that of TGF-β1 mRNA(r =-0.126,P ＞0.05;r = 0.019,P ＞ 0.05).Conclusion The expression of TGF-β1 may be closely correlated with the invasion and metastasis of breast cancer.TGF-β1-induced invasiveness and metastasis of breast cancer cells are mediated by MMP-2 and MMP-9.     

Expression of FRAT1 and β-catenin in human brain glioma and their significances

Objective: To investigate the expression of FRAT1 and β-catenin in human brain glioma, analyze the correlation between the expression and clinical pathological grades and the correlation of the two genes. Methods: FRAT1 and β-catenin were detected by immunohistochemistry in 84 human brain glioma tissues and 6 human normal brain tissues. Results: 66.7% (56/84) and 77.4% (65/84) of human brain glioma tissues expressed FRAT1 and β-catenin protein, whereas no FRAT1 and β-catenin protein expression was detected in human normal brain tissues. The expression levels of FRAT1 and β-catenin increased markedly with the ascending of pathologic grade of tumor specimens (r = 0.55, P < 0.01, r = 0.70, P < 0.01), there was a positive correlation between FRAT1 and β-catenin (r = 0.77, P < 0.01). Conclusion: FRAT1 and β-catenin over-expression maybe closely related with occurrence and development of human brain gliomas. The results provide important supplements for the research of Wnt/β-catenin pathway. Meanwhile, FRAT1 may act as a valuable biomarker for molecular diagnosis of glioma and a potential target for gene therapy of glioma.     

RARα1 control of mammary gland ductal morphogenesis and wnt1-tumorigenesis

Introduction  

Retinoic acid signaling pathways are disabled in human breast cancer suggesting a controlling role in normal mammary growth that might be lost in tumorigenesis. We tested a single receptor isotype, RARα1 (retinoic acid receptor isotype alpha, isoform 1), for its role in mouse mammary gland morphogenesis and mouse mammary tumor virus (MMTV)-wingless-related MMTV integration site 1 (wnt1)-induced oncogenesis.     

Safety and Efficacy of PD-1/PD-L1 Inhibitors in Treatment-Naive and Chemotherapy-Refractory Patients With Non–Small-Cell Lung Cancer: A Systematic Review and Meta-Analysis

Introduction

Programmed death 1 (PD-1)/programmed death ligand 1 (PD-L1) inhibitors show significant clinical activity in non–small-cell lung carcinoma (NSCLC). However, there is a relative lack of data on comparative efficacy of these drugs in the first-line setting versus chemotherapy-treated patients. We compared the efficacy and toxicity of these drugs in these 2 distinct groups of patients.