MicroRNA-based methods and compositions for the diagnosis, prognosis and treatment of solid cancers

1. A method of diagnosing whether a subject has a solid cancer, comprising

measuring in a test sample from the subject a level of miR-21 gene product and miR-191 gene product,

comparing the level of the miR-21 gene product and miR-191 gene product in the test sample to a control level of miR-21 gene product and miR-191 gene product; and

diagnosing whether a subject has a solid cancer selected from the group consisting of colon, lung, pancreas, prostate, and stomach cancer,

wherein an increase in the level of miR-21 gene product and miR-191 gene product in the test sample, relative to the control level of miR-21 gene product and miR-191 gene product, is indicative of the subject having a solid cancer selected from the group consisting of colon, lung, pancreas, prostate, and stomach cancer.

2. A method of claim 1 , comprising:

(1) reverse transcribing miR-21 RNA and miR-191 RNA from a test sample obtained from the subject to provide miR-21 and miR-191 RNA target oligodeoxynucleotide;

(2) hybridizing the miR-21 and miR-191 RNA target oligodeoxynucleotide to a microarray comprising miRNA-specific probe oligonucleotides that include miR-21 RNA and miR-191 RNA specific probe oligonucleotide to provide a hybridization profile for the test sample; and

(3) comparing the test sample hybridization profile to a control hybridization profile,

wherein, if a signal of miR-21 RNA and miR-191 RNA in the test sample hybridization profile is greater than the signal of the miR-21 RNA and miR-191 RNA in the control hybridization profile, then the subject has a solid cancer selected from the group consisting of colon, lung, pancreas, prostate, and stomach cancer.

3. A method of claim 1 , which further comprises measuring at least one miR in addition to measuring miR-21 and miR-191.