Material and Methods: This retrospective cohort study conducted in Turkey included 73 patients diagnosed with PV or ET according to WHO criteria between 2012 and 2018. Vitamin D deficiency was defined as 25-OH vitamin D < 20 ng/mL. Polymerase chain reaction (PCR) was used to detect the Janus kinase 2 (JAK2) V617F mutation.

Results: Vitamin D deficiency was found in 66.7% of PV and 74.2% of ET patients. The median follow-up time of ET and PV patients was 48 months and 47 months, respectively. Patients with the JAK2 mutation had a higher prevalence of a history of thrombosis and age older than 65 years. There was a significant relationship between JAK2 positivity and vitamin D deficiency.

Materials and methods: 3D-mediated inhibition on cell viability was evaluated by MTT and real-time cell proliferation was measured by xCelligence RTDP instrument. Western blotting was used to measure pro-apoptotic, anti-apoptotic proteins and JAK2-STAT3 phosphorylation. Flow cytometry was used to measure ROS production and apoptosis.

Results: Our study revealed that 3D treatment significantly reduced the viability of human CRC cells HT-29 and SW620. Furthermore, 3D treatment induced the generation of reactive oxygen species (ROS) in human CRC cells. Confirming our observation, N-acetylcysteine significantly inhibited apoptosis. This is further evidenced by the induction of p53 and Bax; release of cytochrome c; activation of caspase-9, caspase-7 and caspase-3; and cleavage of PARP in 3D-treated cells. This compound was found to have a significant effect on the inhibition of antiapoptotic proteins Bcl2 and BclxL. The results further demonstrate that 3D inhibits JAK2-STAT3 pathway by decreasing the constitutive and IL-6-induced phosphorylation of STAT3. 3D also decreases STAT3 target genes such as cyclin D1 and survivin. Furthermore, a combination study of 3D with doxorubicin (Dox) also showed more potent effects than single treatment of Dox in the inhibition of cell viability.