Sources/Clones
EGFR
Accurate (21-1, F4), American Qualex, Biodesign (EGFR 1, 2E9, L-4451, F5, E5), Biogenesis (C11, EGFR1), Biogenex (E30), Caltag Laboratories (2E9), Chemicon (polyclonal), Cymbus Bioscience (EGFR1), Dako (EGFR1), Fitzgerald (polyclonal), Immunotech (F4), Novocastra (polyclonal), Oncogene (R.1,225, 455), Pharmingen (c11), Sigma (29.1, F4) and Zymed (Z025).
TGF-a
Biodesign, Biogenesis (2D7/44, 2D7/45,, 8A5/7, Rt, TB21), Chemicon (polyclonal) and Oncogene (134A-2B3, 213. 4-4, 189-2130.1).
Fixation/Preparation
Applicable to formalin-fixed, paraffin-embedded tissue, although an antigen retrieval technique should be used prior to immunostaining, e.g. citrate buffer and microwave oven unmasking. May also be applied to cryostat sections or cell smears.
Background
Transforming growth factors (TGF) were discovered due to their ability to transform fibroblasts to a malignant phenotype (DeLarco and Todaro, 1978). Two distinct polypeptides were subsequently isolated: TGF-a and TGF-b. TGF-a is a polypeptide of 50 amino acids and is acid and heat stable (Prigent and Lemoine, 1992). TGF-a belongs to the epidermal growth factor family, members of which share a common amino acid sequence and biological activities. They also bind to a common receptor, epidermal growth factor receptor (EGFR), on target cells (Carpenter, 1984).
EGFR is a 170 kD protein comprising a cell surface ligand-binding transmembrane domain and a highly conserved cytoplasmic tyrosine kinase domain. When TGF-a binds to EGFR, tyrosine kinase of the receptor is activated. This is followed by phosphorylation and an increase in cytosolic calcium ions within target cells. The resultant effect is an increased DNA synthesis with proliferation and differentiation of the cell (Chen et al, 1989).
TGF-a is a potent growth stimulator and is distributed in both fetal and adult tissues, playing a role in the physiological regulation of normal growth and differentiation (Yasui et al, 1992).
Applications
There is sufficient evidence showing that TGF-a is an important growth factor for transformation of various cell types to a malignant phenotype (Pusztai et al, 1993).The coexpression of both the ligand (TGF-a) and its receptor (EGFR) has been documented in a variety of carcinomas both gastrointestinal and non-gastrointestinal. This bond is thought to confer autonomy to tumor cells by autocrine or paracrine mechanisms (Sporn & Roberts, 1985). Whilst coexistent expression of a growth factor and its receptor would be expected to confer increased growth advantage to tumor cells, the ability of certain tumors to express both growth factor and/or the respective receptor may be lost during the carcinogenic transformation.
The EGFR antibody reacts with the majority of squamous cell carcinomas arising from both squamous epithelium and metaplastic squamous epithelium (Ozanne & Richards, 1986). Studies on breast cancer have shown that the expression of the EGF receptor may also be of prognostic value (Nicholson et al, 1991). 1991).
Comments
Growth factors and their receptors participate in the process of tumorigenesis by promoting the growth of tumor cells. During this process, tumor cells acquire an increasingly aggressive phenotype with loss of the physiological control for growth and differentiation. At the present time the availability of antibodies to growth factors/receptors can only contribute to our understanding of the complex mechanisms involved in tumorigenesis.
References
•Carpenter G 1994 Properties of the receptor for epidermal growth factor. Cell 37: 357-358.
•Chen WS, Lazar CS, Lund KA et al 1989 Functional independence of the epidermal growth factor receptor from a domain required for ligand-induced internalization and calcium regulation. Cell 59: 33-43.
•DeLarco JE, Todaro GH 1978 Growth factors from murine sarcoma virus transformed cells. Proceedings of the National Academy of Sciences USA 75: 4001-4005.
•Nicholson S, Richard J, Sainsburg C et al 1991. Epidermal growth factor receptor (EGFr); results of a 6 year follow-up study in operable breast cancer with emphasis on the node negative subgroup. British Journal of Cancer 63: 146-150.
•Ozanne B, Richards CS 1986 Over-expression of the EGF receptor is a hallmark of squamous cell carcinomas. Journal of Pathology 149: 9-14.
•Prigent SA, Lemoine NR 1992 Type 1 (EGF-R related) family of growth factor receptors and their ligands. Progress in Growth Factor Research 4: 1-24.
•Pusztai L, Lewis CE, Lorenzen J, McGee OD 1993 Growth factors: regulation of normal and neoplastic growth. Journal of Pathology 169: 191-201.
•Sporn MB, Roberts AB 1985 Autocrine growth factors and cancer. Nature 313: 745-747.
•Yasui W, Ji Z-O, Kuniyasu H et al 1992 Expression of transforming growth factor alpha in human tissues. Immunohistochemical study and Northern blot analysis. Virchows Archives A Pathology and Anatomy 421: 513-519.
Bibliografía
Manual of diagnostic antibodies for immunohistology / Anthony S.-Y. Leong, Kumarasen Cooper, F. Joel W.-M. Leong.
EGFR
Accurate (21-1, F4), American Qualex, Biodesign (EGFR 1, 2E9, L-4451, F5, E5), Biogenesis (C11, EGFR1), Biogenex (E30), Caltag Laboratories (2E9), Chemicon (polyclonal), Cymbus Bioscience (EGFR1), Dako (EGFR1), Fitzgerald (polyclonal), Immunotech (F4), Novocastra (polyclonal), Oncogene (R.1,225, 455), Pharmingen (c11), Sigma (29.1, F4) and Zymed (Z025).
TGF-a
Biodesign, Biogenesis (2D7/44, 2D7/45,, 8A5/7, Rt, TB21), Chemicon (polyclonal) and Oncogene (134A-2B3, 213. 4-4, 189-2130.1).
Fixation/Preparation
Applicable to formalin-fixed, paraffin-embedded tissue, although an antigen retrieval technique should be used prior to immunostaining, e.g. citrate buffer and microwave oven unmasking. May also be applied to cryostat sections or cell smears.
Background
Transforming growth factors (TGF) were discovered due to their ability to transform fibroblasts to a malignant phenotype (DeLarco and Todaro, 1978). Two distinct polypeptides were subsequently isolated: TGF-a and TGF-b. TGF-a is a polypeptide of 50 amino acids and is acid and heat stable (Prigent and Lemoine, 1992). TGF-a belongs to the epidermal growth factor family, members of which share a common amino acid sequence and biological activities. They also bind to a common receptor, epidermal growth factor receptor (EGFR), on target cells (Carpenter, 1984).
EGFR is a 170 kD protein comprising a cell surface ligand-binding transmembrane domain and a highly conserved cytoplasmic tyrosine kinase domain. When TGF-a binds to EGFR, tyrosine kinase of the receptor is activated. This is followed by phosphorylation and an increase in cytosolic calcium ions within target cells. The resultant effect is an increased DNA synthesis with proliferation and differentiation of the cell (Chen et al, 1989).
TGF-a is a potent growth stimulator and is distributed in both fetal and adult tissues, playing a role in the physiological regulation of normal growth and differentiation (Yasui et al, 1992).
Applications
There is sufficient evidence showing that TGF-a is an important growth factor for transformation of various cell types to a malignant phenotype (Pusztai et al, 1993).The coexpression of both the ligand (TGF-a) and its receptor (EGFR) has been documented in a variety of carcinomas both gastrointestinal and non-gastrointestinal. This bond is thought to confer autonomy to tumor cells by autocrine or paracrine mechanisms (Sporn & Roberts, 1985). Whilst coexistent expression of a growth factor and its receptor would be expected to confer increased growth advantage to tumor cells, the ability of certain tumors to express both growth factor and/or the respective receptor may be lost during the carcinogenic transformation.
The EGFR antibody reacts with the majority of squamous cell carcinomas arising from both squamous epithelium and metaplastic squamous epithelium (Ozanne & Richards, 1986). Studies on breast cancer have shown that the expression of the EGF receptor may also be of prognostic value (Nicholson et al, 1991). 1991).
Comments
Growth factors and their receptors participate in the process of tumorigenesis by promoting the growth of tumor cells. During this process, tumor cells acquire an increasingly aggressive phenotype with loss of the physiological control for growth and differentiation. At the present time the availability of antibodies to growth factors/receptors can only contribute to our understanding of the complex mechanisms involved in tumorigenesis.
References
•Carpenter G 1994 Properties of the receptor for epidermal growth factor. Cell 37: 357-358.
•Chen WS, Lazar CS, Lund KA et al 1989 Functional independence of the epidermal growth factor receptor from a domain required for ligand-induced internalization and calcium regulation. Cell 59: 33-43.
•DeLarco JE, Todaro GH 1978 Growth factors from murine sarcoma virus transformed cells. Proceedings of the National Academy of Sciences USA 75: 4001-4005.
•Nicholson S, Richard J, Sainsburg C et al 1991. Epidermal growth factor receptor (EGFr); results of a 6 year follow-up study in operable breast cancer with emphasis on the node negative subgroup. British Journal of Cancer 63: 146-150.
•Ozanne B, Richards CS 1986 Over-expression of the EGF receptor is a hallmark of squamous cell carcinomas. Journal of Pathology 149: 9-14.
•Prigent SA, Lemoine NR 1992 Type 1 (EGF-R related) family of growth factor receptors and their ligands. Progress in Growth Factor Research 4: 1-24.
•Pusztai L, Lewis CE, Lorenzen J, McGee OD 1993 Growth factors: regulation of normal and neoplastic growth. Journal of Pathology 169: 191-201.
•Sporn MB, Roberts AB 1985 Autocrine growth factors and cancer. Nature 313: 745-747.
•Yasui W, Ji Z-O, Kuniyasu H et al 1992 Expression of transforming growth factor alpha in human tissues. Immunohistochemical study and Northern blot analysis. Virchows Archives A Pathology and Anatomy 421: 513-519.
Bibliografía
Manual of diagnostic antibodies for immunohistology / Anthony S.-Y. Leong, Kumarasen Cooper, F. Joel W.-M. Leong.
