1H-pyrrolo[2,3-c]pyridin-7(6H)-ones and pyrazolo[3,4-c]pyridin-7(6H)-ones as inhibitors of BET proteins

A method of treating a cancer selected from solid tumor, adenocarcinoma, bladder cancer, blastoma, neuroblastoma, bone cancer, breast cancer, brain cancer, carcinoma, myeloid sarcoma, cervical cancer, colorectal cancer, esophageal cancer, gastrointestinal cancer, glioblastoma multiforme, glioma, gallbladder cancer, gastric cancer, head and neck cancer, intestinal cancer, kidney cancer, laryngeal cancer, lung cancer, lymphoma, liver cancer, small cell lung cancer, non-small cell lung cancer, mesothelioma, ocular cancer, optic nerve tumor, oral cancer, ovarian cancer, pituitary tumor, prostate cancer, pancreatic cancer, pharyngeal cancer, renal cell carcinoma, rectal cancer, sarcoma, skin cancer, spinal tumor, small intestine cancer, stomach cancer, testicular cancer, thyroid cancer, throat cancer, urogenital cancer, urothelial carcinoma, uterine cancer, vaginal cancer, and Wilms' tumor, comprising administering to a patient in need of such treatment a therapeutically effective amount of a compound of Formula IIIa:

• or a pharmaceutically acceptable salt thereof, wherein:
• R1 and R2 are each independently selected from H, methyl, ethyl, propyl, cyclopropyl, cyclopentyl, pyran-4-yl, phenyl, pyridin-2-yl, 2-chloro-4-phenyl, 2-chloro-4-fluorophenyl, and 2-hydroxyethyl;
• or R1 and R2 together with the carbon atom to which they are attached form cyclopropyl;
• R3 is H, methyl, ethyl, or propyl, wherein said methyl is optionally substituted with cyclopropyl, pyridinyl, —C(═O)NH2, —C(═O)NHCH3, —C(═O)(4-methylpiperazin-1-yl), —C(═O)NH(4-methylpiperazin-1-yl), or —C(═O)OH;
• R5 is H, 1-methyl-1H-pyrazol-4-yl, 2-furyl, CN, NO2, methoxy, —C(═O)NH2, —C(═O)NH(CH3), —C(═O)N(CH3)2, —C(═O)-(morpholin-4-yl), —C(═O)CH3, —CH2OH, —CH2OCH3, —CH2NH2, —CH2NHSO2(CH2CH3), —CH2NHC(═O)CH3, —CH(OH)CH3, —SO2CH3, —SO2CH2CH3, —SO2-(isopropyl), —SO2N(CH3)2, —SO2NH(CH3), —SO2—NH(isopropyl), or —SO2-(piperidin-1-yl);
• and
• R7 is methyl.