TEN-010 is a small molecule, bromodomain and extra-terminal domain (BET) bromodomain inhibitor. This study is designed to characterize the safety, tolerability, pharmacokinetics and anti-tumor activity of TEN-010 in patients who are refractory or intolerant to standard/approved therapies. This first-in-human study of TEN-010 will be conducted in two parts: dose escalation and dose expansion. For dose escalation (Part A), a standard "3+3" design will be used in which successive cohorts of three or more patients with advanced solid tumor malignancies will be treated at escalating doses until a maximum tolerated dose (MTD) is identified. For the dose expansion part of the study (Part B), a subset of patients with advanced solid malignancies will be treated with TEN-010 at the MTD (or the highest dose tested if the MTD is not defined) to further characterize safety and biological effect. In addition, up to 10 patients with nuclear protein in testis (NUT) midline carcinoma (NMC) will be permitted to enroll in a substudy of the protocol.