SummaryWe carried out SEREX (serological analysis of antigens by recombinant cDNA expression cloning) using sera from patients with Sjögren's syndrome (SjS) and investigated the frequencies of autoantibodies against autoantigens identified by SEREX in the sera of healthy individuals (HI) and patients with SjS, rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE). IFI16 and two kelch-like proteins, KLHL12 and KLHL7, were found to be novel autoantigens in SjS by SEREX. A markedly high frequency of anti-IFI16 autoantibodies was observed in the sera of SjS (SjS, 70%; RA, 13%; SLE, 33%; HI, 0%). Interestingly, all serum samples from SjS demonstrated immunoreactivity against one or both of IFI16 and SS-B/La. The presence of autoantibodies against KLHL12 and KLHL7 in the sera was significantly specific to SjS (23% and 17%, respectively), as they were not detected in RA, SLE or HI. Furthermore, we confirmed that transcripts of these autoantigens were expressed preferentially in the salivary glands and immuno-privileged testes. Our results suggest these autoantigens may be useful as serological markers for the clinical diagnosis of SjS and may play a crucial role as organ-specific autoantigens in the aetiopathogenesis of SjS. This study warranted clinical evaluations of autoantibodies against IFI16, KLHL12 and KLHL7 in combination with anti-SS-B/La autoantibodies.

This study provides the first evidence for a synergistic ATO/CDDP anticancer (apoptotic) activity in OSCC cells with a favorable DRI, thereby highlighting its potential as a combinational therapeutic regime in OSCC.

Ameloblastoma is a rare odontogenic benign tumor accounting for less than 1% of head and neck tumors. Advanced next generation sequencing (NGS) analyses identified high frequency of BRAF V600E and SMO L412F mutations in ameloblastoma.Despite the existence of whole genomic sequence information from patients with ameloblastoma, entire molecular signature of and the characteristics of ameloblastoma cells are still obscure. In this study, we sought to uncover the molecular basis of ameloblastoma and to determine the cellular phenotype of ameloblastoma cells with BRAF mutations. Our comparative cDNA microarray analysis and gene set enrichment analysis (GSEA) showed that ameloblastoma exhibited a distinct gene expression pattern from the normal tissues: KRAS-responsive gene set is significantly activated in ameloblastoma. Importantly, insulin like growth factor 2 (IGF2), a member of KRAS-responsive genes, enhances the proliferation of an ameloblastoma cell line AMU-AM1 with BRAF mutation. In addition, Toll-like receptor 2 (TLR2) knockdown readily inactivated KRAS-responsive gene sets as well as increases caspase activities, suggesting that TLR2 signaling may mediate cell survival signaling in ameloblastoma cells. Collectively, the findings may help to further clarify the pathophysiology of ameloblastoma and lead to the development of precision medicine for patients with ameloblastoma.

Abstract. carbonic anhydrase 9 (cA9) is a glycoprotein present on the surface of cell membranes. It is expressed in 90% of renal cancer cells, but not in normal kidney tissue. Immunotherapy targeting cA9 is underway, and our group has also conducted a clinical trial using cA9 as a cancer vaccine and confirmed the induction of cytotoxic T lymphocytes, with efficacy in some cases. Expression of CA9 antigen in oral cancer has not been reported in Japan, but our results indicate that immunotherapy targeting cA9 might be possible. We immunohistochemically observed the expression of antigens such as cA9, Ki-67, glucose transporter-1 (glUt-1) and p53 in 107 subjects with oral squamous cell carcinoma, and examined their correlation with clinicopathological parameters. Immunostaining analysis showed expression of cA9 in 98% of oral cancer subjects, and the survival rate was significantly lower in subjects with CA9 antigen expression in 50% or more cells (p<0.05). subjects with poorly differentiated, t4 and lymph node metastasis, or stage IV cancer with high CA9 expression (≥50%) had a worse outcome than those with low cA9 expression. Although glUt-1 expression was observed in 98% of subjects, similarly to cA9 expression, no significant correlation between its expression and the survival rate was seen. However, subjects with lymph node metastasis had significantly higher GLUT-1 expression, demonstrating that glUt-1 could be an indicator of lymph node metastasis. Ki-67 was expressed in 92% of subjects, but no correlation with outcome was observed. expression of p53 was noted in 78% of subjects, and it was found that many oral cancers have p53 genetic abnormalities, but no correlation between p53 and outcome was observed. It was confirmed that CA9 antigen is expressed in most oral cancer subjects, suggesting the possibility of immunotherapy targeting cA9 antigen in oral cancer.

NADPH oxidases, also known as the Nox family, are major sources of reactive oxygen species generation that regulate redox-sensitive signaling pathways. Recent studies have implicated the Nox family in cancer development and progression. However, the involvement of its members in the development of oral squamous cell carcinoma (OSCC) remains to be elucidated. To clarify this issue, we first analyzed mRNA expression of Nox/Duox family members (Nox1, Nox2, Nox3, Nox4, Nox5, Duox1 and Duox2) in five OSCC cell lines. Nox1 and Nox4 mRNAs were highly expressed in four OSCC cell lines. Western blot analysis revealed that the protein expression level of Nox1 was higher than that of Nox4 in the OSCC cell lines. In addition, knockdown of Nox1, but not Nox4, significantly suppressed cell viability and induced apoptosis in the HSC-2 and HSC-3 cells. We also found that a specific AKT inhibitor, perifosine, dose-dependently suppressed OSCC cell growth. Notably, Nox1 knockdown significantly attenuated the phosphorylation level of AKT. Furthermore, both Nox1 knockdown and perifosine treatment markedly enhanced the cisplatin-induced cytotoxic effect. Taken together, our results highlight that the Nox1/AKT signaling pathway plays an important role in cell survival in OSCC cells.