Archive for the ‘Tumor’ Category
Tuesday, May 22nd, 2012
BrdU (5-bromo-2-deoxyuridine) is a thymidine analogue which is incorporated into the cells of DNA synthetic phase. Replicating cells undergo DNA synthesis in a highly regulated, S-phase of the cell cycle. The regulation of cell proliferation is central to tissue morphogenesis during the development of multicellular organisms. Furthermore, loss of control of cell proliferation underlies the pathology of diseases like cancer. As such there is great need to be able to investigate cell proliferation and quantitate the proportion of cells in each phase of the cell cycle (1). Since a cell’s decision to proliferate is made in the G1 phase immediately before initiating DNA synthesis and progressing through the rest of the cell cycle, detection of DNA synthesis at this stage allows for an unambiguous determination of the status of growth regulation in cell cultures. Anti-BrdU antibodies have been successfully employed to determine the cell proliferation in cultured tumor cells with high accuracy (2). Accurate determination of the S-phase fraction in proliferative cells has also been determined using anti-BrdU antibodies in various tissues by immunohistochemistry. (3). Analysis of cell kinetics using BrdU antibodies is advantageous in comparison to the conventional autoradiographic methods due to the regulatory issues with the radioactive materials. BrdU antibodies are a powerful tool to study cell proliferation more rapidly through cell based assays and are highly sensitive. Novus Biologicals offers highly sensitive anti-BrdU antibodies for your research needs with reactivity against different species.
- PMID: 2083223
- PMID: 1280304
- PMID: 21551319
Tags: BrdU, BrdU antibodies, cell cycle, DNA Synthesis, G1 phase, S-phase, Thymidine analog
Posted in Antibodies, Antibody catalog, Antibody database, Antibody suppliers, Cancer, DNA Repair, Tumor | No Comments »
Monday, May 14th, 2012
Epigenetic alterations have come to prominence in biomedical research. In particular, hypermethylation of CpG islands located in the promoter regions of tumor-suppressor genes is now firmly established as an important mechanism for gene inactivation in cancer. Polycomb group (PcG) proteins are epigenetic chromatin modifiers involved in gene silencing, cancer development and the maintenance of adult and embryonic stem cells. One of the most remarkable achievements in the field has also been the identification of the methyl-CpG-binding domain family of proteins, which provide mechanistic links between specific patterns of DNA methylation and histone modifications. Interest in non-allelic histone variants has been renewed, in part because of recent work on H3 (and other) histone variants. However, only in mammals do three non-centromeric H3 variants (H3.1, H3.2, and H3.3) exist (1). Epigenetic changes underlie not only normal, but also pathological development. Bmi1 is recognized as a member of the PcG family of proteins (2). The PcG proteins function within distinct multisubunit complexes and epigenetically regulate gene expression by altering chromatin states at specific promoters. In concordance with its role in stem cells, Bmi-1 has been proposed to maintain cancer stem cell populations (3).
Pluripotent embryonic stem cells (ESCs) have the potential to produce every type of cell in the human body. Pluripotency is a unique epigenetic state, in that ESCs can self-renew, while retaining the potential for multilineage differentiation. OCT4 is highly expressed in pluripotent cells and becomes silenced upon differentiation. Interestingly, the precise expression level of OCT4 determines the fate of embryonic stem cells (4). Nevertheless, further investigations are required to fully elucidate the underlying molecular mechanisms responsible for the maintenance and initiation of pluripotency. Novus Biologicals offers an extensive collection of reagents to investigate epigenetic alterations, including Histone H3.2 K23me2 antibody (NB21-1162), Bmi1 antibody (NBP1-96140) and OCT4 antibody (NB100-2379) and our entire EpiPlus™ line.
- PMID: 16212490
- PMID: 1922340
- PMID: 12714970, PMID: 14574365
- PMID: 19480567
Tags: Bmi1, Bmi1 antibody, Chromatin Modifiers, DNA Methylation, Embryonic Stem Cell Marker, Embryonic Stem Cells, histone modification, Histone Modifications, Histones study, OCT4, Oct4 antibody, pluripotent, Pluripotent Embryonic Stem Cells
Posted in Antibodies, Antibody catalog, Antibody database, Antibody suppliers, Cancer, Epigenetics, Stem Cells, Tumor | No Comments »
Tuesday, May 8th, 2012
The transcription factor beta protein 1 (BP1) is a member of the homeobox gene family and the distal-less subfamily. Expression of BP1 is highly tissue-specific and developmentally restricted. Among different human tissues, BP1 is found to be highly expressed in placenta, kidney and at lower levels in fetal liver (1). Such restricted pattern of expression is compatible with a specific gene function in development and/or differentiation. Transient transfection studies demonstrate that BP1 protein appears to act as a repressor of the human adult beta globin gene, through two silencers upstream of the beta globin gene (2,3). BP1 binding site sequence upstream of beta globin gene in Asian populations has been investigated for the polymorphism in the BP1 binding site upstream of beta globin gene, so as to provide the basis for exploration of relation between polymorphisms in the BP1 binding site and beta globin expression (4,5). Beta globin gene cluster polymorphisms are known to be strongly associated with severity of beta-thalassemia in the Asian populations (6). Recent studies also indicate that BP1 genes are dysregulated in various cancers and some new studies point to an important role for BP1, an isoform of DLX4 homeobox gene, in breast carcinogenesis and progression (7). Current research directed towards the elucidation of the role of BP1 in breast tumorogenesis holds a great promise in establishing BP1 as a novel target for drug therapy. Novus Biologicals offers an extensive selection of BP1 study tools, for Western blots, ELISA, IHC and RNAi including highly specific antibodies with reactivity against different species.
- PMID: 11909945
- PMID: 10087993
- PMID: 15308321
- PMID: 22040981
- PMID: 15551156
- PMID: 17894837
- PMID: 20877436
Tags: beta-thalassemia, BP1, BP1 antibody, Breast Cancer, Breast Cancer Antibodies, DLX4, DLX4 antibody
Posted in Antibodies, Antibody catalog, Antibody database, Antibody suppliers, Cancer, Transcription Regulation, Tumor | No Comments »
Monday, May 7th, 2012
Reactive oxygen species, ROS, are beneficially involved in many signaling pathways that control development and maintain cellular homeostasis. In physiological conditions, a tightly regulated redox balance protects cells from injurious ROS activity, altered balance leads to various pathological conditions including cancer. MAP17 is a small 17-kDa non-glycosylated membrane protein that is overexpressed in many tumors of different origins, including carcinomas. Antibody studies have revealed that tumor cells overexpressing MAP17 show an increased tumoral phenotype associated with an increase in ROS. Increased MAP17 expression also results in enhanced proliferative capabilities both in presence or absence of contact inhibition, decreased apoptotic sensitivity and increased migration in cells. Malignant cell behavior induced by MAP17 is associated with an increased ROS production, and the treatment of MAP17-expressing cells with antioxidants results in a reduction of the tumorigenic properties. MAP17-dependent ROS increase and tumor malignancy are interdependent on its PDZ-binding domain, since disruption of its sequence by point mutations abolishes its ability to enhance ROS production and tumorigenesis (1). PDZ may represent the link between the cell membrane-where it interacts with MAP17-and other cytoplasmic proteins involved in biologic functions such as cell proliferation, differentiation, and ion transport (2). Interestingly, in non-tumor cells MAP17 increases ROS, resulting in senescence or apoptosis. Therefore, in tumor cells, MAP17 could be a marker for increased oxidative stress and could define new therapeutic approaches (3,4). We at Novus Biologicals offer a large number of MAP17 antibodies and support reagents to investigate the potential role in oxidative stress mediated tumorigenesis.
- PMID: 17548903
- PMID: 9461128
- PMID: 8701988
- PMID: 22465409
Tags: Antioxidants, MAP17, MAP17 antibody, Oxidative Stress, PDZ domain, Reactive Oxygen Species, ROS
Posted in Antibodies, Antibody catalog, Antibody database, Antibody suppliers, Apoptosis, Cancer, Tumor | No Comments »
Tuesday, May 1st, 2012
Epithelial-to-mesenchymal transition (EMT) is a critical event in the induction of cell motility and increased survival both under physiological situations like wound healing or development, as well as in malignant cells undergoing invasion and metastasis. Vimentin is an intermediate filament protein which is characteristically upregulated in cells undergoing EMT. Recent studies support the notion that vimentin functions as a positive regulator of EMT and upregulation of vimentin appears to be a prerequisite for EMT induction (1). Vimentin has been shown to be an important regulator of cell motility. In cell culture conditions, vimentin is upregulated at the wound edge in mammary epithelial cells and breast cancer cells (2,3). Additionally it has been shown that fibroblasts lacking vimentin migrate poorly, and display reduced mechanical stability, motility and directional migration towards different chemo-attractive stimuli (4). Furthermore, wounds in vimentin-deficient adult animals showed delayed migration of fibroblasts into the wound site and subsequently retarded contraction that correlated with a delayed appearance of myofibroblasts at the wound site (5). Vimentin has been recognized as a marker for EMT, although EMT is associated with several tumorigenic events, vimentin’s role in the underlying events mediating these processes remains unknown. By virtue of its overexpression in cancer and its association with tumor growth and metastasis, vimentin serves as an attractive potential target for cancer therapy; however, more research would be crucial to evaluate its specific role in cancer (6). Novus Biologicals offers a wide range of Vimentin related products such as poly and monoclonal antibodies, recombinant proteins, ELISA kits, protein lysates and RNAi products.
- PMID: 21686283
- PMID: 21057535
- PMID: 18281472
- PMID: 9625752
- PMID: 10852824
- PMID: 21637948
Tags: Breast Cancer, Breast Cancer Antibodies, Vimentin, Vimentin antibody, Wound healing
Posted in Antibodies, Antibody catalog, Antibody database, Antibody suppliers, Cancer, Tumor | No Comments »
Thursday, April 5th, 2012
Monocyte Chemotactic Protein-1 (MCP-1), also known as Chemokine C-C motif Ligand 2 (CCL2), is a small cytokine involved in immune response, inflammation and tissue repair. Specifically, MCP1 is responsible for recruiting monocytes, memory T cells, and dendritic cells to sites of tissue injury or infection. MCP-1 is produced by a wide range of cell types as a reaction to diverse inflammatory stimuli, and has been implicated in many diseases characterized by monocytic infiltrates, such as psoriasis, rheumatoid arthritis and atherosclerosis.
However, a recent study by Dr. Tsuyada, et al. at the City of Hope’s Beckman Research Institute has identified MCP1 as a key factor in breast cancer disease progression. In the paper (1), researchers investigated the effects of stromal fibroblasts on breast cancer stem cells to find that the CCL2 is significantly upregulated in cancer associated fibroblast cells. The authors found that increased MCP1 protein induced Notch1 expression and lead to the cancer stem cell signaling circuit of breast cancer cells. Furthermore, inhibiting CCL2 expression successfully prevented both Notch1 expression and tumor growth progression. These findings indicate that MCP1 antibodies may soon become useful therapeutic tools to block cancer stem cell-mediated disease progression.
Novus Biologicals offers an extensive selection of MCP1 reagents, including highly specific antibodies, recombinant proteins, ELISA packs, lysates and more!
1. PMID: 22472119
Tags: Atherosclerosis, Breast Cancer Antibodies, CCL2, CCL2 antibody, MCP1, MCP1 antibody, NOTCH1, NOTCH1 antibody, Psoriasis
Posted in Antibodies, Antibody catalog, Antibody database, Antibody suppliers, Cancer, Immunology, Inflammation, Stem Cells, Tumor | No Comments »
Thursday, February 16th, 2012
The matrix metalloproteinases are zinc-dependent protease enzymes which interact with a range of ECM (extracellular matrix) proteins, and are activated by proteolytic cleavage. We at Novus Biologicals offer a wide range of top quality MMP reagents, including MMP3, MMP7, MMP9, MMP13 and MMP2 specific antibodies.
All the above proteins are known to play important roles in embryonic development, wound healing, angiogenesis, carcinogenesis, tumour invasion and apoptosis. Overexpression of MMP2 and MMP9 is associated with tumour migration, metastasis and aggressive, invasive cancers such as chondrosarcomas, malignant astrocytomas, melanomas and breast cancer. It is thought this occurs through degradation of the ECM proteins, primarily Collagen IV and Laminin 5, allowing migration of metastatic cells through the basement membrane, with enhanced tumour growth.
The heat shock protein HSP90 is uploaded at times of cellular stress, with increasing evidence to show that it acts as a molecular chaperone. A recent study by D. Stellas et al. [PMID: 20602761] suggested HSP90 could be a target for antibody therapy. The team used various monoclonal antibodies (mAbs) to probe the interaction of HSP90 isoforms with MMP2 and MMP9. They also examined the role of a new HSP90 mAb, called 4C5, in inhibiting metastasis and metastatic cell invasion, using a mouse model of human breast cancer.
The breast cancer cells secreted HSP90, which then interacted with MMP2 and MMP9 to activate them. MMP9/MMP2 antibody assays showed that while 4C5 antibodies did not restrict the release of inactive MMP2/MMP9 from cancer cells, their activation was blocked through disruption of the extracellular HSP90/MMP binding mechanism by mAb 4C5. This in turn prevented the metastatic deposit of tumour cells into the lung tissue. The conclusion was that 4C5 antibodies could have potential therapeutic use in cancer.
Tags: Collagen IV, Collagen IV antibody, HSP90, HSP90 antibody, Laminin 5, Laminin 5 antibody, MMP antibody, MMP13, MMP13 antibody, MMP2, MMP2 antibody, MMP3, MMP3 antibody, MMP7, MMP7 antibody, MMP9, MMP9 antibody
Posted in Angiogenesis, Antibodies, Antibody catalog, Antibody database, Antibody suppliers, Apoptosis, Cancer, Heat Shock Proteins, Tumor | No Comments »
Wednesday, February 8th, 2012
ATP-binding cassette superfamily F2 (ABCF2) is a member of the ATP-binding cassette (ABC) transporter superfamily, and more specifically, a member of the GCN20 subfamily. Most members of this family are membrane proteins that transport various substrates across the cell membrane [1, 2]. ABC genes have a pair of nucleotide binding folds (NBF) and trans-membrane (TM) domains; ABCF2 differs by having a pair of NBF’s but no TM domains. It is this distinction that leads most researchers to believe that ABCF2 does not have any membrane transport function, but instead may be involved in translational control, antibiotic resistance, and RNase L inhibition [1, 3].
Areas of study that utilize the ABCF2 protein include breast cancer, cervical cancer, clear cell ovarian adenocarcinoma, and endometrial cancer. Studies have found that ABCF2 may play a role in tumor suppression at metastatic sites, the endocrine pathway for breast cancer, and as a useful biomarker for cervical cancer [2, 3, 4]. Some breast cancers, being endocrine dependent cancers, utilize hormones for carcinogenesis. ABCF2 expression has been seen to increase in these types of breast cancer tissues. This suggests that ABCF2 may act as a surrogate marker for endocrine dependent proteins. There is also evidence that there is a relationship between ABCF2 expression and sensitivity to endocrine therapy [2].
The overexpression of ABCF2 was also found in conjunction with ectopic endometriosis [2]. However, ABCF2 expression is not related to prognosis or clinical factors such as age, stage, histologic type, histologic grade, and estrogen receptor status in endometrial cancer [3].
In cervical cancer, ABCF2 expression is found to be higher in stages III and IV. Currently, squamous cell antigen (SCC) is used as a marker for cervical cancer; however, there are conflicting reports on the accuracy of pretreatment SCC measurements as it pertains to prognostic significance [3]. In cervical non-squamous cell carcinoma, ABCF2 expression is prevalent. This ABCF2 expression correlated with overall survival in clinical trials. ABCF2 may therefore be a more useful biomarker for cervical non-squamous cell carcinoma [3].
- Dean, M., Rzhetsky, A., and Allikmets, R. 2001. The Human ATP-Binding Cassette [ABC] Transporter Superfamily. Genome Research. 11: 1156-1166.
- Hiroshi, T., Ito, Y.M., Ohashi, Y., Wong, K., Hashinguchi, Y., Welch, W., Berkowitz, R.S., Birrer, M.J., and Mok, S.C. 2005. Identification of overexpression and amplification of ABCF2 in clear cell ovarian adenocarcinomas by cDNA microarray analyses. Clin Cancer Res. 11: 6880.
- Nishimura, S., Tsuda, H., Miyagi, Y., Hirasawa, A., Suzuki, A., Kataoka, F., Nomura, H., Chiyoda, T., Banno, K., Fujii, T., Susumu, N., and Aoki, D. 2008. Can ABCF2 protein expression predict the prognosis of uterine cancer? British Journal of Cancer. 99: 1651-1655.
- Ogawa, Y., Tsuda, H., Hai, E., Tsuji, N., Yamahgata, S., Tokunaga, S., Nakazawa, K., Tamamori, Y., Ogawa, M., Shimizu, S., Inoue, T., and Nishiguchi, Y. 2006. Clinical role of ABCF2 expression in breast cancer. Anticancer Research. 26: 1809-1814.
Tags: ABCF2, ABCF2 Antibody, Breast Cancer, Cervical Cancer, Estrogen Receptor antibody, Membrane Transport, Ovarian Cancer, Translational Control
Posted in Antibodies, Antibody catalog, Antibody database, Antibody suppliers, Cancer, Tumor | No Comments »
Friday, January 27th, 2012
In the United States, breast cancer is one of the most common cancers and the second leading cause of cancer related deaths in women. According to the American Cancer Society’s most recent estimates for breast cancer in the United States, there are about 200,000 new cases of invasive breast cancer, 60,000 new cases of carcinoma in situ (CIS), and approximately 40,000 deaths from breast cancer this year.
A predisposition to breast and ovarian cancer has been linked to mutations in the BRCA1 and BRCA2 genes. In cells where the BRCA1 and BRCA2 genes are defective, there are indications of gross chromosomal rearrangements and breakage. Antibody studies have shown that the RAD51L1 protein specifically targets and fixes double stranded DNA breaks, which are the main cause of the genomic instability in these cells, via the RAD51-mediated DNA repair system (PMID: 15065660).
RAD51L1 also known as DNA repair protein RAD51 homolog 2, RAD51 homolog B, RAD51-like protein 1, RAD51L1, RAD51B, REC2, and R51H2, is a member of the RAD51 protein family and is involved in the early stages of the homologous recombination repair pathway. Homologous recombination occurs before the cell enters mitosis; during and shortly after DNA replication when sister chromatids are present. The 5’ end of the damaged DNA molecule is cut away and the open 3’ end, where RAD51L1 binds and forms a helical nucleoprotein filament, then invades a similar or identical portion of an another intact DNA molecule (PMID: 19329439). BRCA1 and BRCA2 work in conjunction with the RAD51 paralogues (RAD51C, RAD51D, XRCC2, and XRCC3), and some recombination proteins (RAD52, RAD54, RPA, and EVL) to create the RAD51L1 helical nucleoprotein filament (PMID: 19329439, PMID: 15065660). Studies have found that cells with defective BRCA genes fail to create RAD51L1 filaments, and therefore have a lowered cellular repair capacity that can lead to complications such as unregulated cell division and the formation of cancerous tumors (PMID: 15065660, PMID: 20610542).
Please see our website for antibodies, proteins and other reagents related to RAD51L1, homologous recombination, BRCA1, and BRCA2, or contact our technical support department (technical@novusbio.com) for additional details.
Tags: BRCA1, BRCA1 antibody, BRCA2, BRCA2 antibody, Breast Cancer, DNA Repair, Ovarian Cancer, RAD51L1, RAD51L1 antibody
Posted in Antibodies, Antibody catalog, Antibody database, Antibody suppliers, Cancer, Tumor | No Comments »
Thursday, January 26th, 2012
S100A6 antibodies detect a small calcium binding protein with 2 EF-hand structures and belongs to the S100 family. Calcium binding induces a conformational change of the protein which in turn permits its interaction with several target proteins. It is predominantly expressed in fibroblasts and epithelial cells and has been implicated in several cellular processes such as cell cycle progression, cytoskeleton rearrangement and exocytosis. It is a predominantly cytoplasmic protein however in the presence of calcium ions it might also associate with cell membranes. Its vast array of biological processes may be due to the fact that it has the ability to bind a number of proteins and modulate their function by inducing conformation changes and/or interfering with post-translational modifications.
The upregulation of S100A6 has been reported in a number of tumors and linked to metastasis. Recent studies have demonstrated a strong link between high nuclear expression of S100A6 and poor survival in pancreatic cancer patients. It was concluded that up-regulation of S100A6 is an early event in pancreatic cancer development and that elevated levels of nuclear S100A6 influence the clinical outcome.
S100A6 has also been linked to apoptosis. It has been shown to enhance the cell death rate of cells under apoptotic conditions when upregulated. This is believed to be due to the interaction between S100A6 and Caspase 3 during which S100A6 is thought to modulate the transcriptional regulation of caspase 3 by increasing its promoter activity.
P53 appears to be another protein which S100A6 interacts with. The presence of S100A6 results in higher p53 transcriptional activity which resulted in a higher cell susceptibility to apoptosis induced by hydrogen peroxide. The binding of S100A6 to p53 did not however affect the ability of p53 to bind to DNA.
As S100A6 is further studies, more protein binding partners are bound to be discovered. This may shed more light on the diverse roles that S100A6 plays in a vast array of cellular processes. Novus offers top quality S100A6 antibodies as well as many other related reagents. Please contact our technical support department (technical@novusbio.com) for any additional details.
Tags: Calcium Binding Protein antibody, Caspase 3, caspase 3 antibody, p53, p53 antibody, Pancreatic Cancer, S100A6, S100A6 antibody
Posted in Antibodies, Antibody catalog, Antibody database, Antibody suppliers, Apoptosis, Cancer, Transcription Regulation, Tumor | No Comments »
