Jak2, short for Janus kinase 2, is a key component of the JAK/STAT signaling pathway. This pathway is central for cytokine receptor signaling, playing a vital role in normal hematopoiesis, cytogenesis, and the regulation of various biological processes [3,5].

In diseases, the JAK2/STAT3 signaling pathway has been implicated in the progression of osteoarthritis (OA), where it is involved in cartilage degradation, subchondral bone dysfunction, and synovial inflammation [1]. Pharmacological inhibition of JAK2 can interfere with the signaling of immunomodulatory cytokines and block the constitutive activation of the JAK-STAT pathway seen in certain malignancies, like chronic myeloproliferative neoplasms. However, JAK2 inhibition often leads to cytopenias [2]. There is an approved JAK2 inhibitor showing positive but non-curative effects in myeloproliferative neoplasms (MPNs), along with promising results in autoimmune diseases and cancer [3]. Additionally, somatic JAK2 gene mutation has emerged as a risk factor in cardiovascular diseases, potentially related to a complex thromboinflammatory process [4].

In conclusion, Jak2 is essential for cytokine-mediated signaling, with its dysregulation linked to multiple disease states including OA, malignancies, and cardiovascular diseases. Studies targeting JAK2, such as through inhibitor development, have provided insights into its role in these diseases, aiming to develop more effective therapeutic strategies.

References:

1. Chen, Bo, Ning, Ke, Sun, Ming-Li, Zhang, Xin-An. 2023. Regulation and therapy, the role of JAK2/STAT3 signaling pathway in OA: a systematic review. In Cell communication and signaling : CCS, 21, 67. doi:10.1186/s12964-023-01094-4. https://pubmed.ncbi.nlm.nih.gov/37013568/

2. Hernández Boluda, Juan Carlos, Gómez, Montse, Pérez, Ariadna. 2016. [JAK2 inhibitors]. In Medicina clinica, 147, 70-5. doi:10.1016/j.medcli.2016.02.014. https://pubmed.ncbi.nlm.nih.gov/27033437/

3. Leroy, E, Constantinescu, S N. 2017. Rethinking JAK2 inhibition: towards novel strategies of more specific and versatile Janus kinase inhibition. In Leukemia, 31, 1023-1038. doi:10.1038/leu.2017.43. https://pubmed.ncbi.nlm.nih.gov/28119526/

4. Magyar, Eszter, Újfalusi, Anikó, Czenke, Marianna, Méhes, Gábor. 2024. [Somatic JAK2 gene mutation is an evolving risk factor in cardiovascular diseases]. In Orvosi hetilap, 165, 883-890. doi:10.1556/650.2024.33055. https://pubmed.ncbi.nlm.nih.gov/38852144/

5. Sattler, Martin, Griffin, James D. . JAK2 gets histone H3 rolling. In Cancer cell, 16, 365-6. doi:10.1016/j.ccr.2009.10.009. https://pubmed.ncbi.nlm.nih.gov/19878867/