Therapeutic targeting of CK2 in acute and chronic leukemias
Buontempo, F.; McCubrey, JA; Orsini, E; Ruzzene, M; Cappellini, A; Lonetti, A; Evangelisti, C; Chiarini, F; Evangelisti, C; Barata, JT; Martelli, AM
Phosphorylation can regulate almost every property of a protein and is involved in all fundamental cellular processes. Thus, proper regulation of phosphorylation events is critical to the homeostatic functions of cell signaling. Indeed, deregulation of signaling pathways underlies many human diseases, including cancer. The importance of phosphorylation makes protein kinases and phosphatases promising therapeutic targets for a wide variety of disorders. CK2, formerly known as casein kinase II, was discovered in 1954,  although only recently, and especially over the last two decades, it has become one of the most studied protein kinases, due to its ubiquity, pleiotropy and constitutive activity. In particular, appreciation of its pleiotropy has completely changed our vision of CK2 biology, from an ordinary cell homeostasis-maintaining enzyme to a master kinase potentially implicated in many human physiological and pathological events. CK2 is responsible for about 25% of the phosphoproteome, as it catalyzes the phosphorylation of >300 substrates. This partly explains the CK2 interconnected roles that underlie its involvement in many signaling pathways. However, CK2 prevalent roles are promotion of cell growth and suppression of apoptosis. Accordingly, several lines of evidence support the notion that CK2 is a key player in the pathogenesis of cancer. High levels of CK2 transcript and protein expression, as well as increased kinase activity are associated with the pathological functions of CK2 in a number of neoplasias. It was only over the last decade, after extensive analyses in solid tumors, that basic and translational studies have provided evidence for a pivotal role of CK2 in driving the growth of different blood cancers as well, although the first report demonstrating increased CK2 expression in acute myelogenous leukemia (AML) dates back to 1985. Since then, CK2 overexpression/activity has been demonstrated in other hematological malignancies, including acute lymphoblastic leukemia (ALL), chronic lymphocytic leukemia (CLL) and chronic myelogenous leukemia (CML).  With the notable exceptions of CML and pediatric ALL, many patients with leukemias still have a poor outcome, despite the development of protocols with optimized chemotherapy combinations. Insufficient response to first-line therapy and unsalvageable relapses present major therapeutic challenges. Moreover, chemotherapy, even if successful, could have deleterious long-term biological and psychological effects, especially in children. Furthermore, CML patients can develop resistance to tyrosine kinase inhibitors (TKIs), while both primary chemoresistant and relapsed pediatric ALL cases still remain an unresolved issue.
Buontempo, F., & McCubrey, JA, & Orsini, E, & Ruzzene, M, & Cappellini, A, & Lonetti, A, & Evangelisti, C, & Chiarini, F, & Evangelisti, C, & Barata, JT, & Martelli, AM. (January 2018). Therapeutic targeting of CK2 in acute and chronic leukemias. Leukemia, (32:1), p.. Retrieved from http://hdl.handle.net/10342/8004
Buontempo, F., and McCubrey, JA, and Orsini, E, and Ruzzene, M, and Cappellini, A, and Lonetti, A, and Evangelisti, C, and Chiarini, F, and Evangelisti, C, and Barata, JT, and Martelli, AM. "Therapeutic targeting of CK2 in acute and chronic leukemias". Leukemia. 32:1. (.), January 2018. September 26, 2020. http://hdl.handle.net/10342/8004.
Buontempo, F. and McCubrey, JA and Orsini, E and Ruzzene, M and Cappellini, A and Lonetti, A and Evangelisti, C and Chiarini, F and Evangelisti, C and Barata, JT and Martelli, AM, "Therapeutic targeting of CK2 in acute and chronic leukemias," Leukemia 32, no. 1 (January 2018), http://hdl.handle.net/10342/8004 (accessed September 26, 2020).
Buontempo, F., McCubrey, JA, Orsini, E, Ruzzene, M, Cappellini, A, Lonetti, A, Evangelisti, C, Chiarini, F, Evangelisti, C, Barata, JT, Martelli, AM. Therapeutic targeting of CK2 in acute and chronic leukemias. Leukemia. January 2018; 32(1) . http://hdl.handle.net/10342/8004. Accessed September 26, 2020.