Protein active in humoral hypercalcemia of malignancy-PTHRP

Chemistry: natural resins or derivatives; peptides or proteins; – Proteins – i.e. – more than 100 amino acid residues – Hormones – e.g. – prolactin – thymosin – growth factors – etc.

Patent

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

530395, 530412, 530416, 530417, C07K 1514, C07K 328, C07K 322, C07K 318

Patent

active

051169525

DESCRIPTION:

BRIEF SUMMARY
The present invention relates to proteins active in humoral hypercalcemia of malignancy hereinafter referred to as PTHrP (parathyroid hormone related hormone), ACSF (adenylate cyclase stimulating factor), or BRF (bone releasing factor).
The invention further relates to peptide fragments of ACSF and to the purification and partial sequence determination of PTHrP. The invention also relates to antibodies directed against PTHrP or fragments thereof and kits containing said antibodies useful in the identification of PTHrP. [NOTE: Literature references cited herein ar given in full at the end of the specification.]
Humoral hypercalcemia of malignancy (HHM) is a very common complication of certain cancers, especially squamous cell carcinoma of the lung, in which it contributes substantially to morbidity and mortality (1,2). Cancer-derived humoral factors can elevate blood calcium levels by promoting bone resorption and restricting calcium excretion by the kidney (1-3). Although it was thought for many years that "ectopic" production of parathyroid hormone (PTH) by these cancers was the cause of the HHM syndrome (4,5), it has become apparent that factors other than PTH are responsible (1-3,6-8), including transforming growth factors (TGF's), which are potent promoters of bone resorption (2,3,9-11). There is also evidence for the production by certain cancers of some factor immunologically distinct from PTH, but which resembles PTH in stimulating adenylate cyclase activity in PTH target cells (kidney and bone), by acting either directly on the PTH receptor or on a closely related membrane component. Such a possibility was suspected on the basis of clinical evidence (7), and the activity has been noted in extracts of tumors from patents with HHM (12,13), in conditioned medium from a renal cortical carcinoma cell (14), in tumour extracts and culture conditioned media from animal models of HHM (15,16).
We have found that the BEN cell line, originally established from a hypercalcemic patient with a squamous cell carcinoma of the bronchus (17), produces appreciable amounts of this PTH-like activity, hereinbefore described as PTHrP, that stimulates adenylate cyclase in osteoblast-like cells.
We have now succeeded in purifying and characterizing PTHrP.
According to one aspect of the present invention, there is provided substantially pure PTHrP as hereinafter defined.
According to a further aspect of the present invention, there is provided fragments or sub-units of PTHrP, having PTHrP activity.
The isolation and purification of PTHrP will enable investigations to be carried out to characterize its role in the humoral hypercalcemia of malignancy.
PTHrP or peptide fragments thereof may be used to produce both monoclonal and polyclonal antibody reagents, by methods known per se in the art. For example, antibody reagents may be prepared by immunizing appropriate host animals with PTHrP or peptide fragments thereof either alone or in the presence of adjuvants and/or carrier proteins. Examples of appropriate hosts include mice, rats, rabbits, sheep, horses, goats and cows. Where monoclonal antibody reagents are produced, the techniques generally employed are according to the procedure set out by Kohler et al. (18) and Kennet et al (19).
Antibody reagents directed against PTHrP can be utilized in assays to detect PTHrP activity, for example in whole blood, blood plasma, or other biological fluids. Particularly, such reagents will be of considerable utility in the investigation of, and as an aid to diagnosis in, patients with cancer, chronic renal failure, and other bone diseases in which PTH itself is thought to play a role.
Antibodies prepared against PTHrP and peptide fragments thereof, are also useful as immunohistochemical diagnostic reagents, for the immunolocalization of cells capable of producing 30 PTHrP in various tissues.
For diagnostic purposes, antibody reagents may comprise antibodies directed against PTHrP which have been suitably labelled, with a detectable marker, for example; rhodamine, fluorescein, colloidal g

REFERENCES:
patent: 4968669 (1990-11-01), Rosenblatt et al.
M. Ellison et al., Immunoreactive Calcitonin Production by Human Lung Carcinoma Cells in Culture. Br. J. Cancer 32, 373-379, 1975.
N. H. Hunt et al., Calcitonin-responsive Adenylate Cyclase in a Calcitonin-producing Human Cancer Cell Line. Br. J. Cancer (1977) 35, 777-782, 1977.
T. J. Martin et al., Hormone Receptors and Cyclic Nucleotide Metabolism in Cancer Cells. Clinical Endocrinology 5, Suppl., 373s-386s, 1976.
D. M. Findlay et al., Properties of a Calcitonin Receptor and Adenylate Cyclase in BEN Cells, A Human Cancer Cell Line. Cancer Research 40, 1311-1317, 1980.
V. P. Michelangeli et al., Mechanisms of Calcitonin Induction of Prolonged Activation of Adenylate Cyclase in Human Can. Cells. Journ. of Cyclic Nucleotide & Protein Phosphorylation Res.9:129-142 1983.
J. M. Moseley et al., Photoaffinity Labeling of the Calcitonin Receptor. Pharmac. Ther. vol. 34, pp. 51-58, 1987.
J. D. Zajac et al., Biosynthesis of Calcitonin by Human Lung Cancer Cells. Endocrinology 116:749-755, 1985.
D. M. Findlay et al., Protein Kinase-C-Induced Down-Regulation of Calcitonin Receptors and Calcitonin-Activated Adenylate Cyclase in T47D and BEN Cells. Endocrinology 125:2656-2662, 1989.
D. T. Brown et al., Monoclonal Antibodies Against Two Human Lung Carcinoma Cell Lines. Br. J. Cancer 46:794-800, 1982.
L. Pizurki et al., Factor Derived fr. Human Lung Carcinoma Assoc. w/Hypercalcemia Mimics the Effects of Parathyroid Hormone on Phosphate Transp. in Cult. Renal Epith. Jour. of Bone & Min. Res. 3, 1988.
S. Murray et al., The Coregulation of Secretion and Cytoplasmic Ribonucleic Acid of Chromagranin-A Calcitonin by Phorbol Ester in Cells that Produce both Substances. Endocrinology 122:495-502, 1988.
L. J. Deftos et al., The Parathyroid Hormone-Related Protein Associated with Malignancy is Secreted by Neuroendocrine Tumors. Molecular Endocrinology 3:503-508, 1989.
Rabbani et al., Mar. 1986. Endocrinology 118(3): 1200-1210.
Stewart et al., Jun. 1986. J. Bone Miner Res. 1(3):267-276 (abstract).
D'Souza et al., 1984, Endocrinology 115(5):1746-1752, (abstract).
Sofer et al., 1983. Bio Techniques Nov./Dec., pp. 198-203.
Stewart et al., 1983, Proc. Natl. Acad. Sci. USA 80:1454-1458.
Burtis, W. J. et al., 1986. Endocrinology 118(5):1982-1988, (abstract).
Silve et al., 1985. J. Clin. Endocrinol Metal 60(6):1144-1147, (abstract).
Seshadri et al., 1985. Clin Sci 68(3):321-328, (abstract).
Rodan et al., 1983. J Clin Invest 72(4):1511-1515, (abstract).

LandOfFree

Say what you really think

Search LandOfFree.com for the USA inventors and patents. Rate them and share your experience with other people.

Rating

Protein active in humoral hypercalcemia of malignancy-PTHRP does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Protein active in humoral hypercalcemia of malignancy-PTHRP, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Protein active in humoral hypercalcemia of malignancy-PTHRP will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-421048

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.