Effects of Combined siRNA-TR and-TERT on Telomerase Activity and Growth of Bladder Transitional Cell Cancer BIU-87 Cells

The effects of combined RNA interference(RNAi) of human telomerase RNA(hTR) and human telomerase reverse transcriptase(hTERT) genes on telomerase activity in a bladder cancer cell line(BIU-87 cells) were investigated by using gene chip technology in vitro with an attempt to evaluate the role of RNAi in the gene therapy of bladder transitional cell cancer(BTCC).Three TR-specific double-stranded small interfering RNAs(siRNAs) and three TERT-specific double-stranded siRNAs were designed to target different regions of TR and TERT mRNA.The phTR-siRNA,phTERT-siRNA,and the combination of both plasmids phTR+phTERT-siRNA were transfected into BIU-87 cells.The expression of hTR and hTERT mRNA was detected by quantitative fluorescent reverse transcription-polymerase chain reaction,and a telomeric repeat amplification protocol was applied to detect telomerase activity.Growth inhibition of BIU-87 cells was measured by MTT assay.Gene chip analysis was performed to evaluate the effects of the combined RNAi of hTR+hTERT genes on telomerase activity and growth of BIU-87 cells in vitro.The results showed that the expression of hTERT and hTR mRNA was inhibited by pRNAT-hTERT-Ⅲ,pRNAT-hTR-Ⅲ,and pRNAT-hTR-Ⅲ+hTERT-Ⅲ in BIU-87 cells.The inhibition efficiency of pRNAT-hTERT-Ⅲ,pRNAT-hTR-Ⅲ,pRNAT-hTERT-Ⅲ+pRNAT-hTR-Ⅲ was 67% for TERT mRNA,41% for TR mRNA,57% for TR mRNA and 70% for TERT mRNA in BIU-87 cells respectively.The growth of BIU-87 cells was inhibited and telomerase activity was considerably decreased,especially in the cells treated with combined RNAi-hTR and-hTERT.Gene chip analysis revealed that 21 genes were down-regulated(ATM,BAX,BCL2,BCL2L1,BIRC5,CD44,CTNNB1,E2F1,JUN,MCAM,MTA1,MYC,NFKB1,NFKBIA,NME4,PNN,PNN,SERPINE1,THBS1,TNFRSF1A,and UCC1).The results indicated that hTR-siRNA and hTERT-siRNA,especially their combination,siRNA hTR+hTERT,specifically and effectively suppressed the expression of both hTR and hTERT mRNA and telomerase activity.Molecular biological mechanism by which combined siRNA-TR and-TERT inhibited telomerase activity and growth of BIU-87 cells in vitro may involve the down-regulation of the 21 genes.

CLINICAL SIGNIFICANCES OF THE EXPRESSION OF METALLO- THIONEIN IN FIVE TYPES EPITHELIUM CELL CANCER

Objective： To study the expressions of （CSC）, bladder transitional cell cancer metallothionein and the significances in cervical squamous cell cancer （BTC）, esophageal squamous cell cancer （ESC）, gastral tubular adenocarcinoma （GC） and large intestinal tubular adenocarcinoma （LIC）. Methods： lmmunohistochemical method was used to examine the expression rates of MT in five types of cancer tissue. Results： The expression rates of MT were 75.00% （24/32） in ESC, 52.27% （46/88） in GTC, 59.46% （44/74） in LIC, 64.86% （48/74） in BTC and 58.57% （41/70） in CSC respectively. The positive rates of MT expression were higher in low differentiation and deep muscular group than those in medium or high differentiation and superficial muscular invasion group （P〈0.05）. Conclusion： The expression of MT is related to differentiation degree and invasion degree.

Clinical signification on the expressions of metallothionein in three types cancer of woman

Objective： To study the expressions and significations of metallothionein （MT） in cervical squamous cell cancer （CSC）, bladder transitional cell cancer （BTC） and breast cancer （BC） of woman. Methods： Immunohistochemical method was used to examine the expresses rate of MT in three types of woman cancer tissue. Results： The expressions rates of MT were 54.35% （29146） in BTC, 67.05% （59188） in BC and 57.14% （40/70） in CSC. The positive rate of MT expression was higher in low differentiation group than well differentiation group in BTC and CSC （P 〈 0.05）. Positive of MT in lobular cancer was significance higher than medullary and duct cancers （P 〈 0.05）. Conclusion： The expression of MT is related to differentiation degree, and it is a guidance for clinical choice of chemotherapy project.

Cellular plasticity and metastasis in breast cancer: a pre- and post-malignant problem

As a field we have made tremendous strides in treating breast cancer,with a decline in the past 30 years of overall breast cancer mortality.However,this progress is met with little affect once the disease spreads beyond the primary site.With a 5-year survival rate of 22%,10-year of 13%,for those patients with metastatic breast cancer(mBC),our ability to effectively treat wide spread disease is minimal.A major contributing factor to this ineffectiveness is the complex make-up,or heterogeneity,of the primary site.Within a primary tumor,secreted factors,malignant and pre-malignant epithelial cells,immune cells,stromal fibroblasts and many others all reside alongside each other creating a dynamic environment contributing to metastasis.Furthermore,heterogeneity contributes to our lack of understanding regarding the cells'remarkable ability to undergo epithelial/non-cancer stem cell(CSC)to mesenchymal/CSC(E-M/CSC)plasticity.The enhanced invasion&motility,tumor-initiating potential,and acquired therapeutic resistance which accompanies E-M/CSC plasticity implicates a significant role in metastasis.While most work trying to understand E-M/CSC plasticity has been done on malignant cells,recent evidence is emerging concerning the ability for pre-malignant cells to undergo E-M/CSC plasticity and contribute to the metastatic process.Here we will discuss the importance of E-M/CSC plasticity within malignant and pre-malignant populations of the tumor.Moreover,we will discuss how one may potentially target these populations,ultimately disrupting the metastatic cascade and increasing patient survival for those with mBC.