Means and method for determining tumor cell percentage in a sample

1. A method for determining the percentage of tumor cells in a cell sample of an individual, the method comprising

a. preparing RNA from a cell sample from said individual, said cell sample comprising tumor cells or suspected to comprise tumor cells;

b. determining RNA levels for a set of genes in said RNA sample; and

c. determining the percentage of tumor cells in said cell sample on the basis of the levels of RNA determined for the set of genes,

whereby the set of genes comprises genes having SEQ ID NO: 3 and SEQ ID NO: 14, and

d. selecting a sample for further analyses when the percentage of tumor cells is above a pre-determined threshold.

2. Method according to claim 1 , whereby the sample is a sample comprising breast cells of an individual suffering from a breast tumor or suspected of suffering therefrom.

3. Method according to claim 1 , wherein determining the percentage of tumor cells in a sample on the basis of RNA levels determined for a set of genes comprises comparing the RNA levels of said set of genes having SEQ ID NO: 3 and SEQ ID NO:14, to the RNA levels of said set of genes in a reference sample.

4. Method according to claim 1 , further comprising normalizing the determined RNA levels of the set of genes in the sample.

5. Method according to claim 1 , wherein the percentage of tumor cells in a sample of an individual is determined by a set of probes, wherein said probes are specific for genes having SEQ ID NO: 3 and SEQ ID NO: 14.

6. Method according to claim 5 , wherein the individual is suffering from a breast tumor or suspected of suffering there from.

7. Method according to claim 1 , wherein the percentage of tumor cells in a sample of an individual is determined by a set of primer pairs comprising primer pairs that are specific for genes having SEQ ID NO: 3 and SEQ ID NO: 14.

8. Method according to claim 7 , wherein the individual is suffering from a breast tumor or suspected of suffering there from.

9. Method according to claim 1 , wherein the percentage of tumor cells in a sample of an individual is determined by determining the level of expression of a set of genes comprising genes having SEQ ID NO: 3 and SEQ ID NO: 14 in a sample of an individual.

10. Method according to claim 9 wherein the individual is suffering from a breast tumor or suspected of suffering therefrom.

11. The method according to claim 9 , wherein the method further comprises use of primer pairs that allow the quantitative amplification of said set of genes in the sample.

12. Method of determining a percentage of tumor cells in a sample from an individual suffering from a tumor, or suspected of suffering from a tumor, the method comprising

classifying a sample as having a tumor cell percentage below or above a defined threshold by a method comprising

determining a level of RNA for a set of genes comprising genes having SEQ ID NO: 3 and SEQ ID NO: 14 in a sample from said individual;

determining a similarity value for the level of RNA in the sample and a level of RNA for the set of genes in a patient an individual having no tumor cells; and

classifying the sample as having a tumor cell percentage above the threshold if said similarity value is below a first similarity threshold value, and classifying said sample as having a tumor cell percentage below the threshold if said similarity value exceeds said first similarity threshold value, and

selecting a sample for further analyses when the tumor cell percentage is above the threshold.

13. Method according to claim 12 , whereby the defined threshold is 30%.

14. Method according to claim 12 , whereby the individual is suffering from a breast tumor or suspected of suffering there from.

15. Method according to claim 12 , whereby the set of genes comprises SEQ ID NO: 3 and SEQ ID NO: 14.