Compositions and methods for prostate cancer analysis

Patent metadata

Field	Value
Publication number	US-9632091-B2
Application number	US-201514919388-A
Country	US
Kind code	B2
Filing date	Oct 21, 2015
Priority date	Nov 29, 2011
Publication date	Apr 25, 2017
Grant date	Apr 25, 2017

Abstract

The invention provides methods for diagnosing prostate cancer. The invention also provides novel anti-STEAP-1 antibodies and uses thereof.

First claim

What is claimed is:

1. A method for diagnosing prostate cancer in a test subject, comprising:
a) obtaining a blood sample comprising cancer cells of epithelial origin from the test subject;
b) contacting the cancer cells of epithelial origin with an anti-STEAP1 antibody that specifically binds to the STEAP1 prostate-specific marker with a K D of ≦1000 nM;
c) detecting whether STEAP1 is present on the cancer cells of epithelial origin by contacting the blood sample with an antibody that specifically binds to the STEAP1 prostate-specific marker antibody and detecting binding between STEAP1 and the antibody that specifically binds to the STEAP1 prostate-specific marker; and
d) diagnosing the patient with prostate cancer when the presence of STEAP1 on the cancer cells of epithelial origin is detected;
wherein the anti-STEAP-1 antibody is 15A5, produced by a hybridoma cell having a microorganism deposit number of PTA-12259, and
wherein the detecting is by a method based on immunofluorescent microscopy, flow cytometry, fiber-optic scanning cytometry, or laser scanning cytometry.

2. The method of claim 1 , further comprising determining the amount of the cancer cells that express the prostate-specific marker, wherein such amount is predictive of the stage of prostate cancer in the test subject.

3. The method of claim 1 , further comprising determining the expression level of the prostate-specific marker on the cancer cells.

4. The method of claim 1 , further comprising grading the cancer cells based on their expression level of the prostate-specific marker, and determining the percentage of the cancer cells in each grade.

5. The method of claim 1 , wherein the cancer cells are identified from the blood sample with a capturing composition comprising a ligand that specifically binds to cancer cells of epithelial origin.

6. The method of claim 5 , wherein the ligand is an antibody that specifically binds to an epithelial antigen preferentially expressed on cancer cells.

7. The method of claim 5 , wherein the identified cancer cells are enriched in a cell fraction separated from the blood sample.

8. The method of claim 7 , wherein the cell fraction is separated under a magnetic field.

9. The method of claim 8 , wherein the ligand in the capturing composition is coupled to a magnetic particle.

10. The method of claim 1 , wherein the anti-STEAP-1 antibody is conjugated with a first detectable label.

11. The method of claim 1 , wherein the cancer cells are identified with one or more reagents that allow detection of cancer cells of epithelial origin.

12. The method of claim 11 , wherein the reagents comprise a ligand that specifically binds to a cytokeratin, and wherein the ligand is optionally conjugated with a second detectable label.

13. The method of claim 12 , wherein the reagents further comprise a dye that differentiates cells from non-cell components.

14. The method of claim 13 , wherein the dye is 4′,6-diamidino-2-phenylindole (DAPI).

15. The method of claim 14 , wherein the reagents further comprise a ligand that specifically binds to a leukocyte marker, and wherein the ligand is optionally conjugated with a third detectable label.

16. The method of claim 15 , wherein the ligand to a leukocyte marker is a CD45 antibody.

17. A method of monitoring response to a prostate cancer therapy in a test subject, comprising:
a) contacting a first group of cancer cells of epithelial origin with an anti-STEAP1 antibody that specifically binds to a prostate-specific marker with a K D of ≦1000 nM, wherein the first group of cancer cells are from a first blood sample taken from the test subject;
b) determining the amount of the cancer cells in the first group that express the STEAP1 prostate-specific marker and/or the expression level of the STEAP1 prostate-specific marker in the cancer cells;
c) contacting a second group of cancer cells of epithelial origin with the anti-STEAP1 antibody that specifically binds to a prostate-specific marker with a K D of ≦1000 nM, wherein the second group of cancer cells are from a second blood sample taken from the test subject after a test period of prostate cancer therapy;
d) determining the amount of the cancer cells in the second group that express the STEAP1 prostate-specific marker and/or the expression level of the STEAP1 prostate-specific marker in the cancer cells; and
e) comparing the amount of the cancer cells that express the STEAP1 prostate-specific marker and/or the STEAP1 prostate-specific marker expression level as determined in b) with that in d),
wherein the anti-STEAP-1 antibody is 15A5, produced by a hybridoma cell having a microorganism deposit number of PTA-12259,
wherein the determining is by a method based on immunofluorescent microscopy, flow cytometry, fiber-optic scanning cytometry, or laser scanning cytometry, and
wherein a decrease in the amount of the cancer cells expressing the STEAP1 prostate-specific marker and/or a decrease in the STEAP1 prostate-specific marker expression level in the cancer cells indicates a response to the prostate cancer therapy in the test subject.

Assignees

• Genentech Inc

Inventors

• Atwal Siminder
• Hongo Jo-Anne
• Lackner Mark
• Punnoose Elizabeth
• Rubinfeld Bonnee
• Vij Rajesh

Classifications

• C12N5/0693

  Tumour cells; Cancer cells · CPC title

• G01N33/582

  with fluorescent label · CPC title

• A61P35/00

  Antineoplastic agents · CPC title

• G01N33/4915

  using flow cells (flow cytometry G01N15/14) · CPC title

• C07K16/3069

  Reproductive system, e.g. ovaria, uterus, testes, prostate · CPC title