Sex-determining region Y box 6 (SOX6) has been described as a tumor-suppressor gene in several cancers. Our previous work has suggested that SOX6 upregulated p21Waf1/Cip1(p21) expression in a p53-dependent manner; however, the underlying mechanism has remained elusive. In this study, we confirmed that SOX6 can suppress cell proliferation in vitro and in vivo by stabilizing p53 protein and subsequently upregulating p21. Co-immunoprecipitation and immunocytofluorescence assays demonstrated that SOX6 can promote formation of the p14ARF-HDM2-p53 ternary complex by promoting translocation of p14ARF (p14 alternate reading frame tumor suppressor) to the nucleoplasm, thereby inhibiting HDM2-mediated p53 nuclear export and degradation. Chromatin immunoprecipitation combined with PCR assay proved that SOX6 can bind to a potential binding site in the regulatory region of the c-Myc gene. Furthermore, we confirmed that SOX6 can downregulate the expression of c-Myc, as well as its direct target gene nucleophosmin 1 (NPM1), and that the SOX6-induced downregulation of NPM1 is linked to translocation of p14ARF to the nucleoplasm. Finally, we showed that the highly conserved high-mobility group (HMG) domain of SOX6 is required for SOX6-mediated p53 stabilization and tumor inhibitory activity. Collectively, these results reveal a new mechanism of SOX6-mediated tumor suppression involving p21 upregulation via the p14ARF-HDM2-p53 axis in an HMG domain-dependent manner.

Immunologic response plays an important role in orthodontic tooth movement (OTM) and relapse. Nonsteroidal anti-inflammatory drugs, such as aspirin, affect immune cells and clinical orthodontic treatment. However, the mechanisms by which nonsteroidal anti-inflammatory drugs regulate immune cells to affect orthodontic relapse are unclear. In this study, male Sprague-Dawley rats were grouped as relapse and relapse + aspirin for 10 d after 14 d of OTM. Silicone impressions of the rats' maxillary dentitions were obtained to record the distance of OTM at the indicated time point. CD4 T lymphocytes in spleen were examined by flow cytometry. Serum levels of type 1 T-helper (Th1) cell-associated cytokines tumor necrosis factor α (TNF-α), and interferon γ (IFN-γ) were determined through enzyme-linked immunosorbent assay. The effects of aspirin on CD4 T and Th1 cells were also analyzed in vitro. Aspirin treatment significantly reduced the relapse rate. More interestingly, injection of CD25 neutralizing antibody basiliximab or TNF-α inhibitor etanercept can significantly reduce the relapse rate as well. Correspondingly, aspirin treatment significantly accelerated the decrease of orthodontic force-induced secretion of TNF-α and IFN-γ in serum and the expression of TNF-α and IFN-γ in periodontal ligament during relapse. Furthermore, aspirin treatment in vitro significantly repressed the differentiation of CD4 T and Th1 cells. Overall, results indicated that aspirin treatment can block orthodontic relapse by regulating Th1 cells.

This study aimed to determine the risk factors related to the presence of cardiac sequelae 1 mo after initial onset and to examine the preventive effect of the early administration of high‐dose gamma‐globulin (GG) on cardiac sequelae in patients with Kawasaki disease. Patients treated with high‐dose GG of 2000 ± 100 mg kg‐1 were selected as subjects from the 15th nation‐wide survey in Japan. Univariate and logistic multiple variable analyses were used to test the effects of background variables such as age and gender, variables relating to laboratory findings such as the percentage of neutrophil leucocytes, and variables relating to the GG treatment on the presence of cardiac sequelae. The odds ratios were significantly higher for males (1.48), those younger than 1 y of age (1.71), recurrent cases (2.42), and those with a low haematocrit (>32.5%) (1.45) and high percentage of neutrophil leucocytes (<68%) (1.63). The odds ratio was low for those who started GG administration in less than 6 d from onset between the patients with and without cardiac sequelae. The odds ratio for the duration of GG treatment was not significantly different between those with and without cardiac sequelae. Conclusion: Patients who received early administration of GG, less than 6 d from onset of the disease, had a lower risk than those received GG more than 6 d from the onset. The percentage of neutrophil leucocytes and the haematocrit level are useful indicators in predicting the development of cardiac sequelae.