Methods of evaluating treatment outcome in high grade serous ovarian cancer

A method of determining and selecting a treatment for a patient with, or at risk of developing a cancer, the method comprising:

• obtaining a first sample from the patient comprising one or more cancerous or pre-cancerous cells;
• obtaining a second sample from the patient that is similar to the first sample but does not comprise cancerous or pre-cancerous cells;
• processing the first sample and the second sample to analyze at least one biomarker related to CBX2;
• quantifying the amount of biomarker in the first sample and the second sample, wherein if the amount of CBX2-related biomarker in the first sample is greater than the amount of CBX2-related biomarker in the second sample, the patient is identified as having aggressive or chemoresistant cancer;
• and
• selecting a chemotherapy for the patient that is not a platinum-based chemotherapeutic agent if the patient is identified as having aggressive or chemoresistant cancer, or a chemotherapy that is a platinum-based chemotherapeutic agent if the patient is not identified as having aggressive or chemoresistant cancer.

A method of inhibiting or reducing proliferation in a cancer cell, the method comprising:

• contacting the cell with a compound or molecule that inhibits CBX2 expression;
• allowing the compound to reduce the amount of CBX2 protein in the cell;
• thereby
• reducing or inhibiting proliferation of the cell compared to a control cell that is not contacted with the compound.