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An Epstein‐Barr virus (EBV)—encoded latent membrane protein 1 (LMP1) is a principal oncogene that plays a pivotal role in EBV‐associated malignant tumors including nasopharyngeal cancer (NPC). Recent genomic landscape studies revealed that NPC also contained many genomic mutations, suggesting the role of LMP1 as a driver gene for the induction of these genomic mutations. Nonetheless, its exact mechanism has not been investigated. In this study, we report that LMP1 alters the expression profile of APOBEC3s(A3s), host deaminases that introduce consecutive C‐to‐U mutations (hypermutation). In vitro, LMP1 induces APOBEC3B (A3B) and 3F(A3F), in a nasopharyngeal cell line, AdAH. Overexpression of LMP1, A3B, or A3F induces mtDNA hypermutation, which is also detectable from NPC specimens. Expression of LMP1 and A3B in NPC was correlated with neck metastasis. These results provide evidence as to which LMP1 induces A3s and mtDNA hypermutation, and how LMP1 facilitates metastasis is also discussed., EBV LMP1 induces host cytidine deaminases, APOBECs, in nasopharyngeal cells. TES2 domain is important for LMP1‐induced LMP1 hypermutates host mitochondrial genome.

Objectives A combination of platinum-based chemotherapy and radiotherapy is the standard treatment for nasopharyngeal carcinoma (NPC). However, the efficacy of chemotherapy has reached a plateau. Many autophagy studies suggest that autophagy can either promote or suppress to cancer progression. Thus, a role of autophagy in the acquisition of chemoradioresistance has recently been a notable event. Therefore, we examined the relationship between autophagy and chemotherapy in NPC. Methods The expression of Beclin 1 and microtubule-associated protein light chain 3 (LC3), a marker of autophagy, was determined by immunohistochemistry in the biopsy samples of patients with NPC before and after the first course of chemotherapy. Additionally, to investigate in the effect of autophagy suppression in chemotherapy, NPC cell line C666-1 cells were treated with cisplatin and/or chloroquine, an inhibitor of autophagy. Results The expression of Beclin 1 increased after chemotherapy in all patients. In NPC cell line C666-1, compared to cisplatin alone, combination therapy (cisplatin and chloroquine) reduced cell viability, and promoted cell apoptosis. Conclusions These results suggest that autophagy, represented by Beclin 1, is upregulated after chemotherapy in both in vitro and in vivo NPC studies. Inhibition of autophagy could therefore be new strategy for NPC treatment.

Rodent models mimic the heterogeneity of head and neck cancer (HNC) malignancies and are used to investigate HNC-associated biomarkers and evaluate drug responses. To assess the utility of patient-derived xenografts (PDXs) as an HNC model, 18 tumour samples were obtained from surgical specimens of patients with HNC and implanted into non-obese diabetic severe combined immunodeficient mice. The histological features of PDXs and corresponding patient samples were compared. Furthermore, the present study investigated how PDX responses to anticancer drugs mimic patient clinical responses, as well as the expression of adenosine triphosphate-binding cassette transporters through chemotherapy in an HNC-PDX model. A total of five PDXs from patients with HNC exhibiting high correspondence with histopathological features of the original patient samples were established (establishment rate, 28%). The responses of three PDXs to cisplatin were associated with clinical responses of the patients. ABC transporter expression was augmented in one PDX model after anticancer drug treatment, but not in PBS-treated passaged PDXs. PDX models exhibited similar biological and chemosensitive characteristics to those of the primary tumours. PDXs could be a useful preclinical tool to test novel therapeutic agents and identify novel targets and biomarkers in HNC.

Human papillomavirus (HPV) infection is now identified as a major etiologic factor for oropharyngeal cancer (OPC), and HPV positivity is well established better prognostic marker in OPC. Now, predictable markers for the prognosis of the patients who are stratified by HPV has been investigated in. Semaphorin 3A (SEMA3A) is a well-known axon guidance molecule in the nervous system. It is also known as a tumor suppressor in various cancers. In the present study, we examined the relationships between SEMA3A and clinicopathologic features, especially HPV status, and neoangiogenesis, and its prognostic significance for OPC patients. Thirty-two OPC patients and 17 normal patients were analyzed for SEMA3A expression by immunohistochemical analysis. We also analyzed 22 OPC specimens for CD34 expression as a marker of neoangiogenesis. SEMA3A was significantly downregulated in OPC compared with chronic tonsillitis tissues (p = 0.005). SEMA3A expression was negatively correlated with CD34 expression (r = &minus, 0.466, p = 0.033). Moreover, the higher SEMA3A expression cohort showed better survival than the lower SEMA3A expression cohort regardless of HPV status (p = 0.035). These results suggest that SEMA3A expression is a prognostic marker for survival regardless of HPV status and is associated with anti-angiogenesis in OPC.

Semaphorins were discovered as guidance signals that mediate neural development. Recent studies suggest that semaphorin 3A (Sema3A), a member of the semaphorin family, is involved in the development of several cancers. This study aimed to analyze the association of Sema3A with the clinical features of nasopharyngeal carcinoma (NPC), an Epstein−Barr virus-associated carcinoma, and the Epstein−Barr virus primary oncogene latent membrane protein 1 (LMP1). The expression of Sema3A and LMP1 was immunohistochemically examined in the 35 NPC specimens. The mean expression scores for Sema3A and LMP1 were 20.8% ± 14.5% and 13.9% ± 14.8%, respectively. The expression of Sema3A significantly correlated with that of LMP1 (r = 0.41, p = 0.014). In addition, the Sema3A high cohort showed significantly poorer prognosis than the Sema3A low cohort. Sema3A expression was higher in the LMP1-positive KH-1 and KR-4 cell lines compared to the LMP1-negative HeLa cells. Overexpression of LMP1 in the LMP1-negative AdAH cell line upregulated Sema3A expression, both at the transcriptional and translational level. Finally, Sema3A expression was associated with poor prognosis in patients with NPC. Our data suggest that LMP1 induces the expression of Sema3A, which may promote tumor progression in NPC.

Interferon regulatory factor 7 (IRF7) has oncogenic properties in several malignancies such as Epstein-Barr virus (EBV)-associated lymphoma. However, there is no evidence whether IRF7 is associated with the oncogenesis of nasopharyngeal cancer (NPC), the pathogenesis of which is closely associated with EBV. Herein, we report that expression of IRF7 was increased in normal nasopharyngeal cells that expressed the EBV principal oncoprotein, latent membrane protein 1 (LMP1). In addition, IRF7 was mainly expressed in the nucleus in both normal nasopharyngeal cells and nasopharyngeal cancer cells that expresses LMP1. On immunohistochemical analysis, IRF7 was predominantly localized in the nucleus in biopsy samples of NPC tissues. In total, IRF7 expression was detected with 36 of 49 specimens of these tissues. Furthermore, the expression score of IRF7 correlated with the expression score of LMP1. Moreover, the expression score of IRF7 is associated with cervical lymph-node metastasis, which reflects the highly metastatic nature of this cancer. Taken together, our results suggest that expression of IRF7 is one of the metastatic effectors of LMP1 signalling in EBV-associated NPC.

Objective: Although Japan is a non-endemic area with nasopharyngeal carcinoma (NPC), the proportion of WHO type I NPC in Japan are different from that in non-endemic areas such as North America and Europe. Recently, it is said that not only Epstein-Barr virus (EBV) but also human papillomavirus (HPV) has an influence on NPC in non-endemic areas. The aim of this study is to clarify the influence of HPV on NPC in Japan. Methods: Paraffin-embedded tumor specimens were available for 59 patients with NPC diagnosed between 1996 and 2015. We detected the virus status by p16 immunohistochemistry, HPV PCR, and in situ hybridization for Epstein-Barr virus (EBV)-encoded RNA. Kaplan-Meier curves were used to compare the overall survival by viral status. Results: Among the 59 patients, 49 (83%) were EBV-positive/HPV-negative, 2 (3%) were EBV-positive/HPV-positive, and 8 (16%) were EBV-negative/HPV-negative. All HPV-positive NPCs were co-infected with EBV. There were no significant differences between the overall survival in the three groups (p=0.111). Conclusion: In Japan, HPV was detected in a few patients with NPC, and we suggest that HPV has no influence on NPC carcinogenesis in this population. © 2016 Elsevier Ireland Ltd., Embargo period 12 months

Cisplatin (CDDP) is an important drug for chemotherapy in patients with head and neck squamous cell carcinoma. Nephrotoxicity and lack of an effect on bone invasion are limitations of CDDP. To increase its antitumor effect on bone invasion and reduce toxicity problems, anionic Pt complex (3Pt) has been developed. The present study aimed to characterize the basis of the cytotoxicity of the novel platinum complex 3Pt in comparison with that of CDDP for oral squamous cell carcinoma. The ionic platinum complex was prepared to increase solubility and avoid platinum nephrotoxicity. Furthermore, 3Pt was designed to target bone hydroxyapatite and has germinal bisphosphonate moieties for drug delivery. In vitro antitumor activity was assayed in two oral squamous cell carcinoma cell lines. To investigate the antitumor and nephrotoxic effects of 3Pt, nude mice with OSC‐19 were given 3Pt and CDDP. The in vitro growth‐inhibitory effect of 3Pt was significantly less than that of CDDP. However, both 3Pt and CDDP showed equivalent antitumor effects in vivo. Mice injected with CDDP developed renal cell apoptosis; however, those injected with 3Pt were almost free of renal cell injury. In addition to similar in vivo antitumor effects, 3Pt decreased the volume of bone resorption compared to that with CDDP in a bone invasion model using OSC‐19. In conclusion, considering the potential advantages in terms of noticeable antitumor activity on bone invasion and reduced nephrotoxicity, 3Pt represents a significant improvement in the development of bone‐targeting platinum drugs.

Human papillomavirus (HPV) has been identified as a causative agent of cervical cancer and oropharyngeal cancer (OPC). Intriguingly, estrogen and HPV were shown to play synergistic roles in cervical carcinogenesis. We recently demonstrated that the apolipoprotein B mRNA-editing catalytic polypeptide 3 (APOBEC3, A3) family, which is inducible by estrogen, could lead to HPV DNA hypermutation and cause viral DNA integration. In the present study, we examined the relationships between estrogen-estrogen receptor α (ERα) and A3s in HPV-positive OPC. ERα expression was associated with HPV positivity in OPC biopsy samples using immunohistochemical analysis and reverse-transcription quantitative polymerase chain reaction. In addition, ERα was significantly associated with improved overall survival in HPV-positive OPC (hazard ratio, 0.26; p = 0.029). APOBEC3A (A3A) mRNA was induced by estrogen in HPV and ERα-positive OPC cells. Furthermore, A3A mRNA and protein expression were significantly higher in ERα-positive cases than in ERα-negative ones, among HPV-positive biopsy samples (p = 0.037 and 0.047). These findings suggest that A3A is associated with a good prognosis in ERα-positive OPC, and indicate the prognostic significance of ERα in HPV-positive OPC. This is the first study to demonstrate the prognostic role of ERα in HPV-positive OPC.

Objectives: The objectives of this study were to evaluate the formation of lymphvascular niches in lymph nodes of patients with oral squamous cell carcinoma (OSCC), and investigate the roles of lymphangiogenic and angiogenic factors, such as vascular endothelial growth factor (VEGF)-A, VEGF-C, and VEGF-D, expressed in the primary tumors. Materials and Methods: Forty-four patients with previously untreated clinically late T2 or T3 OSCC of cN0 were evaluated for primary tumors and 166 sentinel lymph nodes (SLNs). Primary tumors were immunohistochemically analyzed for expressions of VEGFs. Densities of lymphatic vessels (LVDpodoplanin) and high endothelial venules (HEVD) in the SLNs were also calculated using antibodies for each marker, podoplanin and MECA-79, respectively. Results: In 25 patients, all lymph nodes were metastasis-negative, whereas, in 19 patients, metastasis was positive for at least one lymph node (either at SLN, non-SLN, or nodal recurrence). From the analyses of 140 SLNs without metastasis, LVDpodoplanin in 50 SLNs of metastasis-positive cases was significantly higher than that in 90 SLNs of metastasis-negative cases (p = 0.0025). HEVD was not associated with lymph node metastasis. The patients with VEGF-A-High or VEGF-D-High tumors had significantly higher LVDpodoplanin than patients with their Low counterparts (p = 0.0233 and p = 0.0209, respectively). In cases with lymph node metastasis, the VEGF-D-expression score was significantly higher than in those without lymph node metastasis (p = 0.0006). Conclusions: These results suggest that lymph node lymphangiogenesis occurs before metastasis in OSCC. VEGF-A and VEGF-D play critical roles in this process. VEGF-D is a potential predictive marker of positive lymph node metastasis in cN0 patients. © 2015 Wakisaka et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

S100A4 has multiple functions in cell cycle progression and cell motility, and has been implicated in cancer invasion. In this study, we examined the expression of S100A4, E-cadherin and its related proteins in oral squamous cell carcinoma (SCC) cell lines with different invasive phenotypes, grade 4C and 4D. Furthermore, grade 4C OSC-19 cells expressing E-cadherin were transfected with S100A4-expression vector and the expression of E-cadherin-related proteins in the stable clone was examined to elucidate the relationship between S100A4 and E-cadherin. Constitutive over-expression of S100A4 in stable transformant of OSC-19 (OSC-19/S100A4) cells led to down-regulation of E-cadherin and beta-catenin. Furthermore, grade 4D invasive cell lines (HOC313 and TSU) expressing S100A4 mRNA did not express E-cadherin, P-cadherin, and beta-catenin, while gamma-catenin protein was only weakly expressed. Thus, the mRNA expression of E-cadherin was reversely correlated with S100A4 expression in oral SCCs. Interestingly, vascular endothelial growth factor-C was up-regulated in OSC-19/S100A4 cells. In summary, S100A4-mediated regulation of E-cadherin expression may play an important mechanism in invasion and metastasis of oral SCC.

Objectives: Epstein-Barr virus (EBV)-related micoRNAs (miRNAs), BamHI-A rightward transcripts (BART)-miRNAs, are released in a stable form from viable cells, which are abundant in patients with EBV-positive nasopharyngeal carcinoma (NPC). We estimated copy numbers of circulating miR-BART2-5p, miR-BART17-5p, and miR-BART18-5p as well as BamHI-W DNA as biomarkers. Materials and Methods: Serums from 31 EBV-positive (confirmed by in situ hybridization for EBV-encoded small RNAs) NPC patients and 40 non-NPC controls were analyzed. Among the 31 NPC patients, serums at the initial diagnosis and three months after treatment were obtained from 20 patients, and serums only at three months after treatment were obtained from 11 patients. Results: The sensitivity/specificity of circulating BamHI-W DNA, miR-BART2-5p, miR-BART17-5p, and miR-BART18-5p for the diagnosis of NPC before treatment were 100/100, 85/85, 60/95, and 25/100%, respectively. For BamHI-W DNA, NPC patients with stage IV disease had significantly higher copy numbers than those with I-III. Copy numbers decreased significantly post-treatment. In contrast, copy numbers of the three BART-miRNAs showed no significant correlation with the clinical stage at diagnosis or any significant post-treatment change. After treatment, BamHI-W DNA and miR-BART17-5p were detected in 5 and 6 cases out of 11 patients with recurrent or residual tumors, respectively. However, BamHI-W DNA and miR-BART17-5p were absent in all 20 patients without relapse or residual tumors. Conclusion: The copy number of circulating BamHI-W DNA is a more useful biomarker for the initial diagnosis of NPC than the three BART-miRNAs examined. Post-treatment detection of miR-BART17-5p is a potential biomarker of a poor prognosis. © 2016 Hirai et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

S100A4 is known to be involved in cancer cell motility by virtue of its ability to activate non-muscle myosin. In the current study, we investigated the interrelationship of clinico-pathological findings and S100A4 expression in oral squamous cell carcinoma (SCC). The expression of S100A4 was examined immunohistochemically in 41 clinical specimens of oral SCC. S100A4 expression was detected in 11 (26.8%) of 41 cases. Although the expression of S100A4 was not associated with the primary tumor site and degree of differentiation, there was a significant correlation between the increased S100A4-expression and the mode of invasion (p < 0.0001). In addition, the S100A4 status showed a clear correlation with lymph node metastasis (P < 0.01). These results lead us to conclude that S100A4 expression status may be a useful prognostic factor in patients with invasive and metastatic oral SCCs.