Methods for Detecting Receptor Complexes Comprising PDGFR
Abstract of the Disclosure The invention is directed to a new class of biomarker in patient samples comprising dimers of ErbB cell surface membrane receptors. In one aspect, the invention includes a method of determining the status of a disease or healthful condition by correlating such condition to amounts of one or more dimers of ErbB cell surface membrane receptors measured directly in a patient sample, in particular a fixed tissue sample. In another aspect, the invention includes a method of determining a status of a cancer in a specimen from an individual by correlating measurements of amounts of one or more dimers of ErbB cell surface membrane receptors in cells of the specimen to such status, including presence or absence of a pre-cancerous state, presence or absence of a cancerous state, prognosis of a cancer, or responsiveness to treatment. Preferably, methods of the invention are implemented by using sets of binding compounds having releasable molecular tags that are specific for multiple components of one or more types of receptor dimers. After binding, molecular tags are released and separated from the assay mixture for analysis.
1. 62. A method for detecting in a biological sample the presence or amount of a receptor complex comprising a Platelet Derived Growth Factor receptor (PDGFR) and a second protein, comprising:
(a) contacting with the sample a binding compound having a molecular tag attached thereto by a cleavable linkage and a cleaving probe having a cleavage inducing-moiety with an effective proximity, wherein the binding compound specifically binds either the PDGFR or the second protein and the cleaving probe specifically binds an opposite member of the receptor complex from that bound by the cleaving probe;
(b) cleaving the cleavable linker of the binding compound within the effective proximity of the cleavage-inducing moiety of the cleaving probe, thereby releasing the molecular tag; and
(c) identifying the released molecular tag to determine the presence or amount of the receptor complex comprising the PDGFR and the second protein in the sample.
2. 63. The method of claim 62 , wherein the second protein is a cell surface receptor.
3. 64. The method of claim 63 , wherein the second protein is Her1.
4. 65. The method of claim 63 , wherein the second protein is Her2.
5. 66. The method of claim 63 , wherein the second protein is Her3.
6. 67. The method of claim 62 , wherein the binding compound comprises an anti- PDGFR antibody.
7. 68. The method of claim 62 , wherein the binding compound comprises an anti-Her1 antibody.
8. 69. The method of claim 62 , wherein the binding compound comprises an anti-Her2 antibody.
9. 70. The method of claim 62 , wherein the binding compound comprises an anti-Her3 antibody.
10. 71. The method of claim 62 , wherein the cleaving probe comprises an anti- PDGFR antibody.
11. 72. The method of claim 62 , wherein the cleaving probe comprises an anti-Her1 antibody.
12. 73. The method of claim 62 , wherein the cleaving probe comprises an anti-Her2 antibody.
13. 74. The method of claim 62 , wherein the cleaving probe comprises an anti-Her3 antibody.
14. 75. The method of claim 62 , wherein the biological sample comprises cancer cells.
15. 76. The method of claim 75 , wherein the cancer cells are obtained from a patient.
16. 77. The method of claim 76 , wherein the biological sample is obtained by a biopsy of the cancer.
17. 78. The method of claim 76 , wherein the biological sample is obtained by purifying circulating cancer cells from the patient's blood.
18. 79. The method of claim 75 , wherein the cancer is a lung cancer.
19. 80. The method of claim 75 , wherein the cancer is a breast cancer.
20. 81. The method of claim 62 , wherein the step of detecting is preceded by electorphoretically separating the molecular tag.
21. 82. The method of claim 62 , wherein the cleavage-inducing moiety is a photosensitizer.