A method for determining the prognosis for survival of a patient having cancer is disclosed, said cancer being altered (i.e. highly activated or alternatively inactive/inhibited) in the NMDAR signalling pathway, said method comprising determining the expression levels of a plurality of gene products in a sample from a cancer patient relative to a control, wherein the differential expression of said plurality of gene products relative to a control is indicative of cancer aggressiveness and of the patient's prognosis. A method for improving the prognosis for a cancer patient being diagnosed to have a poor prognosis, as well as pharmaceutical compositions for that purpose, are also disclosed, said method comprising modulating the level or the activity of the identified gene products and/or a member of the NMDA signalling pathways and/or a DLGAP family gene products and/or a HSF1 gene product and/or a FMR1 gene product.