Opioid Receptor Antibodies Trifecta

This publication proposes a role for opioid receptors in treating cancers. It also references use of our μ, δ, and κ opioid receptor antibodies.

Kohei Yamamizu1, Sadayoshi Furuta, Shiori Katayama, Michiko Narita, Naoko Kuzumaki, Satoshi Imai, Hiroshi Nagase, Tsutomu Suzuki, Minoru Narita, and Jun K. Yamashita. The κ opioid system regulates endothelial cell differentiation and pathfinding in vascular development. Blood July 21, 2011 vol. 118 no. 3 775-785.

Highlights: The opioid system is, thus, a new regulator of vascular development that simultaneously modifies 2 distinct vascular properties, EC differentiation and vascular pathfinding. We confirmed that KOR, but not MOR, was highly expressed in various ECs such as HUVECs (data not shown), suggesting that KOR agonists could directly act on tumor ECs to suppress VEGF receptor expression, similar to the effects observed in embryonic ECs. If so, a combination therapy including an MOR agonist, morphine, and a KOR agonist (such as TRK820, a clinically approved drug in Japan for uremic pruritus) may prove useful for cancer therapy through the suppression of tumor angiogenesis by dual inhibition of VEGF ligands and receptors, extending the therapeutic benefits beyond pain relief.

Images: KOR was highly expressed in Flk1⁺ vascular progenitors. (A) RT-PCR showing mRNA expression of MOR, DOR, and KOR in ES cells, Flk1⁺ cells, cells after 1 or 3 days of Flk1⁺ cell culture (Flk-d1 or Flk-d3), CD31-positive cells (ECs) and CD31-negative cells (MCs) at Flk-d3. (B) Fluorescent staining for MOR, DOR, and KOR at Flk-d1. Nuclei are stained with DAPI (blue). Left, MOR; middle, DOR; right, KOR. Scale bars, 100 μm. (C) Double fluorescent staining for MOR, DOR, and KOR with CD31 (red) at Flk-d3. Nuclei are stained with DAPI (blue). Top, opioid (green) receptors (green); middle, CD31 (red); bottom, merged. Scale bars, 100 μm.

Is Neuropathy Really Gliopathy?

I found this excellent website from posting by Dr. Jan M. Keppel Hesselink, Professor molecular pharmacology, director Institute neuropathic pain: http://www.neuropathie.nu/. It represents a new way of understanding root causes and potential therapies for Neuropathic Pain. Here're highlights:

Gliopathic pain: is a brand new term for what we always thought to be neuropathic pain. It refers to pain related to neuropathic pain, however, the primary driver of this pain is most probably more linked to glia and asterocytes. The mechanism of gliopathic pain is the hyperactivation of glia cells, which results in neuropathic pain.

The role of Glia and Astrocytes:Glia and astrocytes play a central role in neuropathic pain, and gliopathic pain, or asteropathic pain will become new synonyms for neuropathic pain. In a recent hallmark paper the term 'Gliopathic pain' was coined.

This is a reason to put our magnifying glass on glia. Gliamodulating drugs will become a new class of neuropathic drugs, the so called gliopathic modulating drugs, and the first prototype, the endogenous fatty acid palmitoylethanolamide, has already been explored in positive proof of principle studies.

For more than a century doctors are aware of the special properties of glia in response to injury. In Germany in 1894 professor Franz Nissl decribed the reaction of glial cells in relation to the nerve fibers in the spinal cord and highlighted their morphological changes after injury. Microglia becomes mores bigger and more abundant after injury and these glial responses can be seen as a biological reponse to promote nerve repair after injury. However, this response can go berzerk and might be one of the most important mechanisms leading to neuropathic pain.

This is a short synopsis. There is a wealth of more information on the website. That said, I will be posting more on Gliopathic Pain.

Primary Neurons and Cell Based Assays

The feedback I receive from Neuroscientists is consistent. To paraphrase, "gives us healthy, consistent and potent primary cells. I understand the hard work it takes to generate meaningful and publishable results from cell based assays. Our Primary Neurons and Astrocytes are merely inputs for these assays. The real cost is the time invested in culturing and time lost if they don't work.

I have numerous postings on success: Primary Neurons Postings. I wanted to share more data and feedback.

Primary DRGs-Culturing these can be tricky. I make it a point to work with labs to make sure the protocol options best match the desired outcome for assays. This includes replacing cells to make sure we can accurately troubleshoot. This approach insures I can pin point the issues and make sure they are all resolved in round two. Here's a representative testimonial: "Thanks for following up, the DRGs worked great and we were able to get excellent data from them. Thanks so much for working with us." Adam Ross, Dr. Chengji Zhou Lab, UC Davis

Image: DRGs cultured on Calf Skin Collagen.

Primary Hippocampal Neurons-I would like to thank Vimal Swarup, University of Utah for this excellent image.

The cells have been fixed after 48 hrs, they were grown over poly-lysine coated coverslips in the media supplied by Neuromics. Cells were imaged in phase contrast mode with 40x objective.

Put our primary cells to the test!

MOR and NMDAR Interplay-Implications in Pain Control

Our Opioid Receptor Antibodies continue to be referenced in publications by Pain Researchers. Many of these studies provide a greater understanding of how opioids alleviate pain and what modulates this ability.

For example, the capacity of opioids to alleviate inflammatory pain is negatively regulated by the glutamate-binding N-methyl-D-aspartate receptor (NMDAR). This study drills down into the specifics of this regulation and references use of Neuromics' MOR1C Antibody: María Rodríguez-Muñoz, Pilar Sánchez-Blázquez, Ana Vicente-Sánchez, Esther Berrocoso and Javier Garzón. María Rodríguez-Muñoz, Pilar Sánchez-Blázquez, Ana Vicente-Sánchez, Esther Berrocoso and Javier Garzón. The Mu-Opioid Receptor and the NMDA Receptor Associate in PAG Neurons: Implications in Pain Control. Neuropsychopharmacology , (3 August 2011) | doi:10.1038/npp.2011.155.

Abstract: The capacity of opioids to alleviate inflammatory pain is negatively regulated by the glutamate-binding N-methyl-D-aspartate receptor (NMDAR). Increased activity of this receptor complicates the clinical use of opioids to treat persistent neuropathic pain. Immunohistochemical and ultrastructural studies have demonstrated the coexistence of both receptors within single neurons of the CNS, including those in the mesencephalic periaqueductal gray (PAG), a region that is implicated in the opioid control of nociception. We now report that mu-opioid receptors (MOR) and NMDAR NR1 subunits associate in the postsynaptic structures of PAG neurons. Morphine disrupts this complex by protein kinase-C (PKC)-mediated phosphorylation of the NR1 C1 segment and potentiates the NMDAR–CaMKII, pathway that is implicated in morphine tolerance. Inhibition of PKC, but not PKA or GRK2, restored the MOR–NR1 association and rescued the analgesic effect of morphine as well. The administration of N-methyl-D-aspartic acid separated the MOR–NR1 complex, increased MOR Ser phosphorylation, reduced the association of the MOR with G-proteins, and diminished the antinociceptive capacity of morphine. Inhibition of PKA, but not PKC, CaMKII, or GRK2, blocked these effects and preserved morphine antinociception. Thus, the opposing activities of the MOR and NMDAR in pain control affect their relation within neurons of structures such as the PAG. This finding could be exploited in developing bifunctional drugs that would act exclusively on those NMDARs associated with MORs.

I will continue to post these studies. They give hope for pain sufferers as many propose potential new druggable targets.

Plasma netrin-1 is a diagnostic biomarker of human cancers

I am pleased to report broadening application for our Stem Cell Markers as a diagnostic for cancers. This publication references use of our Netrin-1 antibody.

Ganesan Ramesh, Arthur Berg, and Calpurnia Jayakumar. Plasma netrin-1 is a diagnostic biomarker of human cancers. Biomarkers. Author manuscript; available in PMC 2011 July 26. Published in final edited form as: Biomarkers. 2011 March; 16(2): 172–180. Published online 2011 February 8. doi: 10.3109/1354750X.2010.541564.
Objectives: To determine whether plasma netrin-1 can be used as a diagnostic biomarker of human cancer.

Materials and Methods: A total of 300 cancer plasma samples from breast, renal, prostate, liver, meningioma, pituitary adenoma, glioblastoma, lung, pancreatic and colon cancer patients were compared against 138 control plasma samples. Netrin-1 levels were quantified by ELISA and immunohistochemistry.

Results: Plasma netrin-1 levels were significantly increased in breast, renal, prostate, liver, meningioma, pituitary adenoma, and glioblastoma cancers as compared to control samples.

Discussion and Conclusion: Our results suggest that plasma netrin-1 can be used as a diagnostic biomarker for many human cancers.

Image: Immunohistochemical localization of netrin-1 in renal cell carcinoma (RCC) tissues. A. Secondary antibody control showing no staining. B. Normal adjacent tissues do not show any staining for netrin-1. C. Stage I RCC shows staining for netrin-1. D. Stage II RCC shows staining for netrin-1. E-F.


Netrin-1 Immunohistochemistry: Stage I–III renal cell carcinoma and normal tissue section (Tissue Array) was obtained from Biomax to immunolocalize netrin-1, as described previously (29). Briefly, tissue sections were dewaxed and rehydrated with graded ethanol (100%, 90%, 70% and 30%) and then washed with PBS. Antigen retrieval was carried out using citrate buffer and steamer. The tissue section was permeabilized with 0.2% Triton X-100 in PBS, and washed and blocked with PBS containing 5% donkey serum and 1% BSA. Primary antibodies included a chicken anti-netrin-1 polyclonal antibody (Neuromics cat # CH23002). Primary antibodies were detected using secondary antibodies conjugated with biotin, which was followed by incubation with streptavidin-horseradish peroxidase (Pierce). Slides were mounted in permount and photographed using an Olympus microscope attached to a CCD camera.
Potent diagnostic tools for cancers save lives. This is especially true of markers that can diagnose them in early stages. I will post these important studies as the cross my radar scope.

SOX2 and Initiation of Breast Tumors

I consider it a feather in Neuromics' cap when our reagent(s) are referenced in a Nature Journal. More importantly it enables me to keep the pulse on novel and important discovery.

This pub references use of one of our SOX2 Antibody and comes from Dr. Angel García Martín and his Team at INBIOMED: O Leis, A Eguiara, E Lopez-Arribillaga, M J Alberdi, S Hernandez-Garcia, K Elorriaga, A Pandiella, R Rezola and A G Martin. Sox2 expression in breast tumours and activation in breast cancer stem cells. Oncogene , (8 August 2011) | doi:10.1038/onc.2011.338.

The important insight from this study is: "Over-expression of Sox2 increased mammosphere formation, effect dependent on continuous Sox2 expression; furthermore, Sox2 knockdown prevented mammosphere formation and delayed tumour formation in xenograft tumour initiation models. Induction of Sox2 expression was achieved through activation of the distal enhancer of Sox2 promoter upon sphere formation, the same element that controls Sox2 transcription in pluripotent stem cells. These findings suggest that reactivation of Sox2 represents an early step in breast tumour initiation, explaining tumour heterogeneity by placing the tumour-initiating event in any cell along the axis of mammary differentiation."

Could these findings ultimately lead to a better diagnostic for Breast Cancer? I'll keep you posted.

Lab Highlights: Breast cancer is the most frequent cancer in women making up to 20% of all tumours diagnosed in women, with 1 million new cases diagnosed every year worldwide (16,000 new cases only in Spain). Worlwide it causes over 350,000 deaths with an increasing tendency. Breast cancer stem cells show the phenotype CD44+/CD24low/-Lin- though only a fraction of this population has the capacity to initiate tumours. Therefore a complete and precise description of the breast cancer stem cells is lacking.

The focus of this laboratory is to identify, isolate and culture breast cancer stem cells from natural breast tumours and compare at the molecular level with normal mammary stem cells. This research involves the stablishment of both in vitro and in vivo functional assays and the molecular characterization (both genomic and proteomic) of breast cancer stem cells to define the mechanisms responsible for its transformed phenotype.

High Content and High Throughput Toxicity Screening

Kits designed for Drug Discovery and Development

Our customers have been impressed with the capablities of our in vivo and in vitro apoptosis and toxicity kits. Here's a recent pub referencing use of one of our FLICA™ in vitro Caspase Kits: Giovanna Grandinetti, Nilesh P. Ingle, and Theresa M. Reineke. Interaction of Poly(ethylenimine)–DNA Polyplexes with Mitochondria: Implications for a Mechanism of Cytotoxicity. Mol. Pharmaceutics, Article ASAP Publication Date (Web): June 23, 2011 Copyright © 2011 American Chemical Society...inhibitor of caspases (FLICA) specific for caspase-9 (Neuromics, Inc)...
Images: Jurkat cells were treated with 1 µM staurosporine for 3 hours to induce caspase 9 activity (top), or were treated with a control (bottom). Both populations were incubated with ICT’s green FAM-LEHD-FMK FLICA™ caspase 9 reagent. DIC images were taken of both samples. Almost all cells in the induced sample (top) fluoresce green therefore they have activated caspase 9. None of the control cells (bottom) fluoresce green, therefore they do not have activated caspase 9 Courtesy of Dr. Brian Lee, ICT

Neuromics is pleased to announce the addition of HemoGenix® Predictive in vitro Toxicity and Apoptosis Kits:

Solutions for predictive in vitro toxicity and apoptosis are now important than ever. These kits enable you to do high throughput and high content screening of stem cells, progenitors and primary cells.
Kit options include:

•LumiSTEM™-96 iPS and LumiSTEM™-iPS HT Assays to Study Induced Pluripotent Stem Cells (iPS) and Toxicity to iPS Cells and Cells Derived from iPS Cells.

•LUMENESC™-Tox HT (LUMENESC™-96 Tox and LUMENESC™-384 HT). A Toxicity Screening and Testing Platform for Cells of the Mesenchymal Stem/Stromal Cell System.

•HALO®-Tox HT Predictive Hemotoxicity Platform using HALO®-96 Tox and HALO®-384 HT. A Highly Predictive, In Vitro Stem and Progenitor Cell Hemotoxicity Screening and Testing Platform for all Stages of Drug Development and Xenobiotic.

I will continue to post regarding progress.