effect of sortilin silencing on ovarian carcinoma cells

Our preliminary data on the protein expression of SORT1 in ovarian carcinoma tissues showed that sortilin was overexpressed in ovarian carcinoma patients and cell lines, while non-malignant ovaries expressed comparably lower amount of this protein. In spite of diverse ligands and also different putative functions of sortilin [NTR3], the function of overexpressed sortilin in ovarian carcinoma cells is an intriguing subject of inquiry. The aim of this study was, therefore, to investigate the functional role of sortilin in survival of ovarian carcinoma cell line. Expression of sortilin was knocked down using RNAi technology in the ovarian carcinoma cell line, Caov-4. Silencing of SORT1 expression was assessed using real-time qPCR and Western blot analyses. Apoptosis induction was evaluated using flow cytometry by considering annexin-V FITC binding. [3H]-thymidine incorporation assay was also used to evaluate cell proliferation capacity. Real-time qPCR and Western blot analyses showed that expression of sortilin was reduced by nearly 70-80% in the siRNA transfected cells. Knocking down of sortilin expression resulted in increased apoptosis [27.5 +/- 0.48%] in siRNA-treated ovarian carcinoma cell line. Sortilin silencing led to significant inhibition of proliferation [40.1%] in siRNA-transfected Caov-4 cells as compared to mock control-transfected counterpart [p<0.05]. As it was suspected from overexpression of sortilin in ovarian tumor cells, a cell survival role for sortilin can be deduced from these results. In conclusion, the potency of apoptosis induction via silencing of sortilin expression in tumor cells may introduce sortilin as a potential candidate for developing a novel targeted therapy in patients with ovarian carcinoma

Construction and stable expression of a truncated human receptor tyrosine kinase ror1 [Ror1-ECD]

Expression of receptor tyrosine kinase Ror1 in a wide variety of cancers has emerged as a new era focusing on targeting this receptor in cancer therapy. Our preliminary results indicate the presence of a truncated transcript of Ror1 in tumor cells. The truncated Ror1 encompasses extracellular and transmembrane domains, lacking catalytic kinase domain [Ror1-ECD]. As enzyme activity is highly dependent on the catalytic domain, we were wondering how this transcript and its encoded protein could play a possible role in tumorigenesis. To understand the function of this truncated transcript and whether or not the encoded protein translocates to the cell surface, we construct-ed a mammalian expression vector containing exon 1 to exon 8 of human Ror1 gene as a model system. The encoded protein by this construct covers the entire extracellular and transmembrane domains of Ror1. The Chinese Hamster Ovary Cell line [CHO] was used for transfection. Our results showed that this construct could express Ror1-ECD at protein level and also the protein could effectively translocate to the surface of transfected cells. Such model may suggest that a proportion of Ror1 molecules ex-pressed by tumor cells are not full-length Ror1. This notion may be considered when applying flow cytometry using antibodies against Ror1 for screening of tumor cells in order to avoid any miscalculation in the number of Ror1 molecules expressed by tumor cells. Furthermore, such expression may bring about assumptions on functional roles of Ror1-ECD in tumorigenesis, which requires extensive functional studies

Peptide-based Polyclonal Antibody Production against P110 Protein of Mycoplasma genitalium

Mycoplasma genitalium [M.genitalium] is a sexually transmitted pathogen. Detection of this microorganism in clinical specimens by culture is rather difficult and time consuming. The aim of this study was to produce polyclonal antibody against a synthetic peptide from P110 protein of M.genitalium in order to develop a diagnostic tool for detection of this microorganism in clinical specimens. A synthetic peptide from P110 protein was conjugated to Keyhole Limpet Hemocyanin]KLH[and used for immunization of a white New Zealand rabbit. The produced antibody was purified by affinity chromatography and its specific interaction with immunizing peptide was determined by ELISA. Immunoreactivity of the antibody was also tested by Western blotting in bacterial cell lysate prepared from M.genitalium G-37. To confirm its application as a diagnostic tool, indirect immunofluorescent staining method was performed on M.genitalium-infected PBMC using anti-P110 as the primary antibody. The results showed that produced antibody has excellent reactivity with immunizing peptide and also detected a single band of 110 kDa corresponding to P110 protein. M.genitalium-infected PBMC showed a bright fluorescent signal in IF staining. This antibody might be used as a tool in diagnostic applications

Expression of ROR1 in patients with renal cancer-a potential diagnostic marker

The ectopic expression of receptor tyrosine kinase Rorl has been reported in patients with hematological malignancies such as chronic lymphocytic leukemia and acute lymphoblastic leukemia. Here we report, for the first time, expression of ROR1 gene in both tumor tissues and peripheral blood mononuclear cells [PBMC] from patients with renal cancer [RC]. In the current study, the expression of ROR1 gene was semi-quantitatively measured in PBMC and tumor tissues from 16 RC patients as well as PBMC from 22 healthy individuals relative to the expression of the housekeeping gene phosphoglucomutase 1 by RT-PCR. Our results showed that ROR1 was expressed at gene level in 81.3% of renal tumor tissues [13 out of 16] whereas it was expressed in 94% of PBMC from RC patients [15 out of 16]. A weak expression of RORl was observed in PBMC of 4 out of 22 healthy individual. A significant expression of ROR1 was observed in PBMC from RC patients when compared to that in PBMC from normal healthy individuals [P<0.001]. The expression of ROR1 in PBMC may reflect a shedding of tumor cells into blood stream. We conclude that detection of a high level of ROR1 expression in blood cells might assist in early detection of renal malignancies, providing taking into consideration the clinical symptoms of the disease

Production of monoclonal antibody against human nestin

We have employed a peptid-based antibody generation protocol for producing antibody against human nestin. Using a 12-mer synthetic peptide from repetitive region of human nestin protein devoid of any N-or O-glycosylation sequences, we generated a mouse monoclonal antibody capable of recognizing human, mouse, bovine, and rat nestin. A wide variety of nestin proteins ranging from 140-250 kDa was detected by this antibody. This antibody is highly specific and functional in applications such as ELISA, flow cytometry, immunocytochemistry, and Western blot assays

Conjucation of R-Phycoerythrin to a polyclonal antibody and F [ab'] 2 fragment of a polyclonal antibody by two different methods

R-phycoerythrin [R-PE], a fluorescent protein from phycobiliprotein family, is isolated from red algae. Conjugation of antibodies to R-PE facilitates multiple fluorescent staining methods. In the present study polyclonal antibodies and polyclonal F[ab']2 fragment antibodies were conjugated to R-PE by two different methods. The efficiency of the methods was evaluated using Immunocytochemistry [ICC] and Sodium Dodecyl Sulfate Polyacrylamide Gel Electrophoresis [SDS-PAGE]. In the first conjugation method, PE was attached to SMCC linker followed by conjugation of antibody to PE-SMCC. In the second method, SH groups were added onto R-PE molecule, while the antibody was attached to SPDP linker. Then, the antibody-SPDP molecule was conjugated to R-PE. Our results showed that the two conjugation methods did not have any abrogative effects on the antibody binding activity

effect of human gonadotropin treatment on recipient mouse germ cell proliferation following spermatogonial stem cell transplantation of neonatal donor mice

Spermatogonia are the male germ line stem cells whose life long expansion is needed for permanent production of spermatozoa. The present study was designed to examine the effect of hCG treatment on germ cell proliferation following stem cell transplantation in mice. Spermatogonial stem cells were isolated from neonatal mice testes and characterized by alkaline phosphatase, immunoreactivity and morphological analysis. hCG was injected into normal and cell transplanted mice. We then evaluated the testosterone levels and cell number in normal mice. After that, cyclin B1 gene expression was investigated in transplanted mice. Different doses of busulfan were injected to investigate the effects of chemotherapy on morphological criteria and preparation of recipient mice for transplantation. In this report we show proliferative potential of spermatogonial stem cells after cytotoxic treatment, transplantation efficiency by semi-quantitative RT-PCR, and hCG effect on stem cell regeneration in normal mice and following cell transplantation. The results indicate the spermatogonial stem cells can proliferate after transplantation, and the efficiency of their transplantation depends on hormonal treatment. Therefore, hormonal treatment after stem cell transplantation will be a powerful avenue for increasing the efficiency of transplantation and fertility restoration

Producing recombinant mTEX101; a murine testis specific protein

Production of antibodies against specific proteins of testis germ cells is of great significance for the investigation of processes involved in spermatogenesis, study of infertility problems and determination of the probable role of these proteins as cancer-testis antigens. Murine Testis Specific Recombinant Protein 101 [mTEX101] is a 38kDa, GPI-anchored protein which is expressed in testis germ cells of adult mice but it seems to be absent in other tissues. The structure and function of mTEX101 is not completely understood yet, but it is speculated that it may transduce biochemical signals into the cytoplasm since mTEX101 does not have an intracellular domain but the precise mechanisms are still ambiguous. RNA was extracted from three adult mice testis. The RNA was used in RT-PCR, employing a pair of specific primers for mTEX101 ORF region. TA-cloning technique was performed by the insertion of mTEX101 into a pGEM-T Easy Vector, followed by its subcloning into a His-tagged expression vector, pET-28a [+]. The recombinant mTEX101 was then produced by transfection of the expression vector into BL 21 [DE3] E. coli strain. A recombinant protein, weighing 27kDa, was produced upon IPTG-induction of the bacterial host. The presence of mTEX101 protein was detected through Western blot analysis by anti-mTEX101 peptide antibodies. We produced mTEX101 recombinant protein that could be used for the production of mono and polyclonal antibodies

Construction of a high efficiency PCR products cloning T vector using pGEM-5zf[+]

A highly efficient cloning vector was constructed for cloning PCR products by inserting an 80 bp DMA fragment into pCEM-5zf [+] vector. The Xcm I digestion of this vector gave rise to a 3 overhanging deoxythymidine offering the possibility of cloning PCR products with 3' adenosine overhang created by Taq DMA polymerase. Furthermore, two EcoR I sites were added to the construct for identification of recombinant plasmids using a single restriction enzyme. Taken together, the more efficient cloning performance and the lower cost of this vector as compared to the commercial T vector, suggests that it may be one of the best T vectors for cloning of PCR products

Ectopic expression of sortilin 1 [NTR-3] in patients with ovarian carcinoma

Gene expression profiling of ovarian carcinoma tissues has shown an increase of four-fold expression of SORTl gene. Sortilin 1 [NTR-3] is a 95-100 kDa protein normally expressed in heart, brain, placenta, skeletal muscle, spinal cord, thyroid, and testis. However, its expression has never been reported in normal ovary. Here, we report expression of sortilin 1 in ovarian carcinoma tissues both at gene and protein levels. Sortilin 1 was expressed in all ovarian carcinoma patients [n=15] as well as ovarian carcinoma cell lines [n=5] regardless of their phenotypic characteristics. Non-malignant ovaries [n=6] did not express sortilin 1. The molecular basis for this ectopic expression is not yet clear. Our results showed a major cell surface expression of sortilin 1 rather than ER-Golgi compartment where it is mainly expressed. This finding may introduce sortilin 1 as a novel tumor marker for diagnosis of ovarian carcinoma and may signify its therapeutic value in targeted therapy