METHODS OF DRUG THERAPY SELECTION FOR BREAST CANCER PATIENTS BASED ON HER2 AND HER3 PATHWAY SUBTYPING
Provided herein is a method for determining whether a human subject with breast cancer will respond to a therapy comprising a tyrosine kinase inhibitor or a biologic. The method includes determining the expression level and/or activation level of various signal transduction molecules such as truncated HER2 protein, full-length HER2 protein, HER3 protein, PI3K protein, and others. The determination of likely response to a tyrosine kinase inhibitor therapy or a biologic therapy involves comparing the expression level and/or activation level of the signal transduction molecule(s) to a reference expression/activation level for the specific signal transduction molecule(s).
1 . A method for determining whether a human subject with breast cancer will respond to therapy with a tyrosine kinase inhibitor or a biologic, the method comprising:
(a) lysing a breast cancer cell obtained from a sample from the human subject to produce a cellular extract;
(b) determining an expression level of truncated HER2 protein, an expression level of full-length HER2 protein, an activation level of full-length HER2 protein, an activation level of HER3 protein, and/or an activation level of PI3K protein in the cellular extract;
(c) comparing the expression level of truncated HER2 protein, the expression level of full-length HER2 protein, the activation level of full-length HER2 protein, the activation level of HER3 protein, and/or the activation level of PI3K protein in the cellular extract to a reference expression level of truncated HER2 protein, a reference expression level of full-length HER2 protein, a reference activation level of full-length HER2 protein, a reference activation level of HER3 protein, and/or a reference activation level of PI3K protein, and
(d) determining whether a human subject with breast cancer will respond to therapy with a tyrosine kinase inhibitor or a biologic based upon a difference between the expression level of truncated HER2 protein, the expression level of full-length HER2 protein, the activation level of full-length HER2 protein, the activation level of HER3 protein, and/or the activation level of PI3K protein in the cellular extract compared to the reference expression level of truncated HER2 protein, the reference expression level of full-length HER2 protein, the reference activation level of full-length HER2 protein, the reference activation level of HER3 protein, and/or the reference activation level of PI3K protein.
2 . The method of claim 1 , wherein the breast cancer is HER2-positive, locally advanced breast cancer.
3 . The method of claim 1 , wherein the tyrosine kinase inhibitor is a pan-HER inhibitor or a dual HER1/HER2 inhibitor.
4 . The method of claim 3 , wherein the pan-HER inhibitor is selected from the group consisting of neratinib, afatinib, dacomitinib, poziotinib, and combinations thereof.
5 . The method of claim 3 , wherein the dual HER1/HER2 inhibitor is selected from the group consisting of lapatinib, AZD8931, BIBW 2992, and combinations thereof.
6 . The method of claim 1 , wherein the biologic is selected from the group consisting of a monoclonal antibody, an affibody, a probody, a diabody, a dual antibody, fragments thereof, and combinations thereof.
7 . The method of claim 6 , wherein the monoclonal antibody is an anti-HER2 antibody or an antibody that inhibits HER dimerization.
8 . The method of claim 7 , wherein the anti-HER2 antibody is trastuzumab.
9 . The method of claim 7 , wherein the antibody that inhibits HER dimerization is pertuzumab.
10 . The method of claim 1 , wherein the therapy is used as neoadjuvant therapy.
11 . The method of claim 10 , wherein the neoadjuvant therapy further comprises paclitaxel, doxorubicin, cyclophosphamide, or combinations thereof.
12 . The method of claim 1 , wherein the human subject will likely respond to therapy with a tyrosine kinase inhibitor when the expression level of truncated HER2 protein in the cellular extract is higher than the reference expression level of truncated HER2 protein.
13 . The method of claim 12 , wherein the reference expression level of truncated HER2 protein is a median expression level of truncated HER2 protein in human subjects who did not respond to the tyrosine kinase inhibitor, in human subjects who did not respond to the biologic, and/or in human subjects who responded to the biologic.
14 . The method of claim 13 , wherein the human subject will likely respond to therapy with the tyrosine kinase inhibitor when the expression level of truncated HER2 protein in the cellular extract is about 3-fold to about 5-fold higher than the median expression level of truncated HER2 protein.
15 . The method of claim 12 , wherein the expression level of truncated HER2 protein in the cellular extract is a ratio of the expression level of truncated HER2 protein in the cellular extract to an expression level of a control protein.
16 . The method of claim 15 , wherein the control protein is cytokeratin (CK).
17 . The method of claim 16 , wherein the human subject will likely respond to therapy with the tyrosine kinase inhibitor when the expression level of truncated HER2 protein in the cellular extract is higher than a reference expression level of truncated HER2 protein corresponding to a ratio of about 0.44 relative to the expression level of CK.
18 . The method of claim 1 , wherein the human subject will likely respond to therapy with either a tyrosine kinase inhibitor or a biologic when the expression level of full-length HER2 protein in the cellular extract is higher than the reference expression level of full-length HER2 protein.
19 . The method of claim 18 , wherein the reference expression level of full-length HER2 protein is a median expression level of full-length HER2 protein in human subjects who did not respond to the tyrosine kinase inhibitor.
20 . The method of claim 19 , wherein the human subject will likely respond to therapy with the tyrosine kinase inhibitor when the expression level of full-length HER2 protein in the cellular extract is about 2.5-fold higher than the median expression level of full-length HER2 protein.
21 . The method of claim 18 , wherein the reference expression level of full-length HER2 protein is a median expression level of full-length HER2 protein in human subjects who did not respond to the biologic.
22 . The method of claim 21 , wherein the human subject will likely respond to therapy with the biologic when the expression level of full-length HER2 protein in the cellular extract is about 2.5-fold higher than the median expression level of full-length HER2 protein.
23 . The method of claim 18 , wherein the expression level of full-length HER2 protein in the cellular extract is a ratio of the expression level of full-length HER2 protein in the cellular extract to an expression level of a control protein.
24 . The method of claim 23 , wherein the control protein is cytokeratin (CK).
25 . The method of claim 24 , wherein the human subject will likely respond to therapy with the tyrosine kinase inhibitor when the expression level of full-length HER2 protein in the cellular extract is higher than a reference expression level of full-length HER2 protein corresponding to a ratio of about 38.7 relative to the expression level of CK.
26 . The method of claim 24 , wherein the human subject will likely respond to therapy with the biologic when the expression level of full-length HER2 protein in the cellular extract is between a reference expression level of full-length HER2 protein corresponding to a ratio of from about 5.6 to about 38.7 relative to the expression level of CK.
27 . The method of claim 24 , wherein the human subject will likely not respond to therapy with either the tyrosine kinase inhibitor or the biologic when the expression level of full-length HER2 protein in the cellular extract is lower than a reference expression level of full-length HER2 protein corresponding to a ratio of about 5.6 relative to the expression level of CK.
28 . The method of claim 1 , wherein the human subject will likely respond to therapy with a tyrosine kinase inhibitor when the activation level of full-length HER2 protein in the cellular extract is higher than the reference activation level of full-length HER2 protein.
29 . The method of claim 28 , wherein the reference activation level of full-length HER2 protein is a median activation level of full-length HER2 protein in human subjects who did not respond to the tyrosine kinase inhibitor, in human subjects who did not respond to the biologic, and/or in human subjects who responded to the biologic.
30 . The method of claim 29 , wherein the human subject will likely respond to therapy with the tyrosine kinase inhibitor when the activation level of full-length HER2 protein in the cellular extract is about 3-fold to about 7-fold higher than the median activation level of full-length HER2 protein.
31 . The method of claim 28 , wherein the activation level of full-length HER2 protein in the cellular extract is a ratio of the activation level of full-length HER2 protein in the cellular extract to an expression level of a control protein.
32 . The method of claim 31 , wherein the control protein is cytokeratin (CK).
33 . The method of claim 32 , wherein the human subject will likely respond to therapy with the tyrosine kinase inhibitor when the activation level of full-length HER2 protein in the cellular extract is higher than a reference activation level of full-length HER2 protein corresponding to a ratio of about 3.1 relative to the expression level of CK.
34 . The method of claim 33 , wherein the human subject will likely not respond to therapy with either the tyrosine kinase inhibitor or the biologic when the activation level of full-length HER2 protein in the cellular extract is lower than a reference activation level of full-length HER2 protein corresponding to a ratio of about 0.3 relative to the expression level of CK.
35 - 54 . (canceled)
55 . The method of claim 1 , wherein the expression level of truncated HER2 protein, the expression level of full-length HER2 protein, and the activation level of full-length HER2 protein is determined.
56 . The method of claim 1 , wherein the expression level of full-length HER2 protein and the activation level of HER3 protein is determined.
57 . The method of claim 1 , wherein the method further comprises determining an expression level and/or an activation level of one or more additional signal transduction molecules in the cellular extract.
58 . The method of claim 57 , wherein the one or more additional signal transduction molecules is selected from the group consisting of AKT, PRAS40, ERK1 (MAPK3), ERK2 (MAPK1), RSK, and combinations thereof.
59 . The method of claim 1 , wherein the sample is a breast tumor tissue, whole blood, serum, or plasma sample.
60 . The method of claim 59 , wherein the breast tumor tissue sample is a needle biopsy sample.
61 . The method of claim 1 , wherein the expression level of truncated HER2 protein, the expression level of full-length HER2 protein, the activation level of full-length HER2 protein, the activation level of HER3 protein, and/or the activation level of PI3K protein is determined with Collaborative Enzyme Enhanced Reactive ImmunoAssay (CEER).
62 . The method of claim 1 , wherein the method further comprises administering the tyrosine kinase inhibitor or the biologic to the human subject.