Abstract:Objective To investigate the expression changes and significance of α kinase 1 （ALPK1）, a member of the α kinase family, in cartilage tissue of knee osteoarthritis （OA）. Methods Twenty-five patients who underwent knee OA surgery in Pizhou Hospital affiliated to Xuzhou Medical University from July 2018 to October 2022 were retrospectively selected, and cartilage tissue samples of the patients’ knee joints were collected. In addition, the tibial plateau cartilage of 10 patients who underwent lower limb amputation due to trauma in the biological sample of the hospital was selected as the control. Immunohistochemical (IHC) staining, Western blotting and real-time quantitative PCR （RT-qPCR） were used to detect the expression of ALPK1 in cartilage. Results The results of IHC staining, Western blotting and RT-qPCR showed that compared with the control group, the mRNA expression level of ALPK1 （2.126±0.930 vs 0.995±0.049, t=4.112, P＜0.01）, protein expression level （1.880±0.722 vs 1.025±0.062, t=3.706, P＜0.01） and IHC-positive cell rate （P＜0.01） in the cartilage of knee OA patients were significantly increased. Conclusion The high expression of ALPK1 in cartilage of patients with kee OA may be one of the reasons for the increase of inflammation and destruction of articular cartilage. ALPK1 is expected to be a diagnostic marker and therapeutic target of kee OA.