The present invention provides novel methods and kits for diagnosing the presence of cancer within a patient, and for determining whether a subject who has cancer is susceptible to different types of treatment regimens. The cancers to be tested include, but are not limited to, prostate, breast, lung, gastric, ovarian, bladder, lymphoma, mesothelioma, medulloblastoma, glioma, and AML. Identification of therapy-resistant patients early in their treatment regimen can lead to a change in therapy in order to achieve a more successful outcome. One embodiment of the present invention is directed to a method for diagnosing cancer or predicting cancer-therapy outcome by detecting the expression levels of multiple markers in the same cell at the same time, and scoring their expression as being above a certain threshold, wherein the markers are from a particular pathway related to cancer, with the score being indicative or a cancer diagnosis or a prognosis for cancer-therapy failure. This method can be used to diagnose cancer or predict cancer-therapy outcomes for a variety of cancers. The markers can come from any pathway involved in the regulation of cancer, including specifically the PcG pathway and the “stemness” pathway. The markers can be mRNA, microRNA, DNA, or protein.