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Objective: Inhibition of apoptosis may favor the onset and progression of cancer. Survivin is an inhibitor of apoptosis that has been considered as a potential marker for diagnostic and/or prognostic of bladder cancer. The survivin protein regulates both cell division and cell death and is overexpressed in the vast majority of human cancers. In this study, the expression pattern and potential prognostic value of survivin was assessed in Formalin-Fixed Paraffin-Embedded (FFPE) samples of bladder tumor. Materials and Methods:FFPE samples, from patients with a well-known five-year survival record, were assessed by semi-quantitative RT-PCR technique. 51 samples from 30 patients were analyzed on the basis of Survivin expression. Tissue distribution and subcellular localization of survivin protein in tumor tissues was also examined by immunohistochemistry (IHC). Results: The expression of survivin was detected in 66.6% of the samples, with an increase of expression in higher grades of tumor. Furthermore, survivin was overexpressed in 2nd and 3rd recurrences of the same patients. Also, with the increased malignancy and accordingly increased expression of surviving, the overall 5-year survival rate of patients was significantly declined (P=0.036). IHC results also localized a nuclear localization for Survivin protein in tumor tissues. Conclusion: In conclusion, we were able to detect the expression of survivin in FFPE samples of bladder tissues, at the level of mRNA and protein and find a correlation between the level of Survivin expression and the degree of malignancy of the tumors. Our findings introduce Survivin as a suitable prognostic marker for predicting the bladder tumors.

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Objective: Because of the necessity of more effective treatments for the nervous system injuries and considering the role of survivin in cellular proliferation and apoptotic cell death, we have monitored survivin gene expression changes during the course of regeneration in injured sciatic nerves and also L4-L6 segments of spinal cord. Materials and Methods: We used adult male NMRI mice as a model. After anesthetizing the animals, the right sciatic nerve was transected and at the indicated times (3, 6, 12, 24, 48, 96 and 144 hours) the animals were sacrificed and both distal and proximal segments of the transected sciatic nerve, intact left sciatic nerve and L4-L6 segments of spinal cord were dissected. The total RNA was extracted from each sample and semi-quantitative RT-PCR with specific primers for survivin and also 2-microglobulin genes, as an internal control, was performed. To determine cellular distribution of survivin protein, 6 days (144 hours) after the axotomy, survivin protein expression was evaluated using immunohistochemistry technique. Results: Our results demonstrated the expression of both survivin140 and survivin40 in distal and proximal segments of sciatic nerve with different intensity, where the expression of survivin140 was higher than survivin40. In spinal cord segments, only survivin140 expression was detected. In Immunohistochemistry analysis of spinal cord segments, both the nuclear and cytoplasmic distribution of survivin protein was observed. In contrast, survivin protein has not been detected in either distal or proximal segments of sciatic nerve. Conclusion: Our data suggest that survivin is differentially expressed and spliced during the course of regeneration in damaged nerve and spinal cord. It seems that manipulation of expression and/or splicing of survivin could potentially affect the process of regeneration in nerve and/or spinal cord injuries.

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Inhibitor of apoptosis (IAP) are a family of proteins that block cell death through caspase activity. Survivin is smallest IAPs family member that overexpresses in different cancer types but not in normal tissue except embryonic tissue. Survivin may be used as a new marker to stratify cancer patients for more optimal treatment modalities. The aim of the current study was to investigate survivin DNA cloning into pET-28a and its expression in E.coli.
The sequence of survivin gene was amplified by PCR using specific primers and pcDNA-survivin temple. PCR product and pET-28a plasmid were digested by HindIII/NheI restriction enzymes and survivin was ligated into the digested vector. Then, the ligation product was transformed into the E.coli DH5a competent cells and screened by antibiotic selection marker (kanamycin). Positive colonies were selected by colony PCR and screened by double digestion of isolated plasmid. One positive colony was sequenced and confirmed. The recombinant plasmid was transformed into the expression strain of E.coli (BL21) by chemical method. The expression of survivin was induced in the different conditions and expression level investigated by SDS-PAGE.
The size of PCR product in agarose gel showed the correctness of amplification. The digested pET-28a plasmid also indicated the correctness of enzymatic reaction. The sequence of the cloned fragment revealed a 100% similarity to the human survivin. In expressing, adding IPTG increased the expression of survivin protein in all conditions, especially 37 ᵒC from 2 h after induction. At all conditions, most of survivin accumulated in the bacteria as inclusion body.
 

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Objective: The greatest challenge in cancer gene therapy is to achieve the high specificity and efficiency in targeting of cancer cells. Because the goal of cancer gene therapy is to eradicate cancer cells, many therapeutic genes could be detrimental if unintentionally expressed in normal cells. Using promoter of the genes which are expressed specifically in cancer cells or have much more expression in cancer cells than normal cells, is very noticeable tool in cancer gene therapy (CGT). In this study we were searching for cancer specific promoter which could highly express therapeutic gene. Materials and methods: In order to apply a cancer specific promoter for creating a CGT construct, a promoter which have 34% similarity to Survivin core promoter was amplified from human genome by using Nested-PCR. Survivin is a member of anti-apoptotic gene and its over-expression was observed in up to 70% of breast cancers. This gene fragment contains two transcriptional binding sites which were similar to Survivin promoter according to the evaluation of Promoter Scan, EPD, Transfac, Compel and TRRD program. These binding sites were recognized by STAT1 and E2F transcription factors. This promoter was cloned into pCDNA3.1/Hygro+ plasmid in along with hypoxia and estrogen modules and pro-apoptotic gene tBid. Results: Semi-quantitative RT-PCR results of transfected cancer cells showed that this gene fragment (Survivin like promoter) have relatively same potential as CMV promoter to direct tBid gene expression. Conclusion: Utilization of chimeric promoter containing Survivin like promoter could be a promising tool in killing cancer cells naturally by inducing apoptosis. This construct is highly effective in transcriptional targeting of tBid in comparison to control construct.