FOXM1-Mediated Regulation of Reactive Oxygen Species and Radioresistance in Oral Squamous Cell Carcinoma Cells.

Radioresistance is a major obstacle to the successful treatment of oral squamous cell carcinoma (OSCC). To help overcome this issue, we have developed clinically relevant radioresistant (CRR) cell lines generated by irradiating parental cells over time, which are useful for OSCC research. In the present study, we conducted gene expression analysis using CRR cells and their parental lines to investigate the regulation of radioresistance in OSCC cells. Based on gene expression changes over time in CRR cells and parental lines subjected to irradiation, forkhead box M1 (FOXM1) was selected for further analysis in terms of its expression in OSCC cell lines, including CRR cell lines and clinical specimens. We suppressed or upregulated the expression of FOXM1 in OSCC cell lines, including CRR cell lines, and examined radiosensitivity, DNA damage, and cell viability under various conditions. The molecular network regulating radiotolerance was also investigated, especially the redox pathway, and the radiosensitizing effect of FOXM1 inhibitors was examined as a potential therapeutic application. We found that FOXM1 was not expressed in normal human keratinocytes but was expressed in several OSCC cell lines. The expression of FOXM1 was upregulated in CRR cells compared with that detected in the parental cell lines. In a xenograft model and clinical specimens, FOXM1 expression was upregulated in cells that survived irradiation. FOXM1-specific small interfering RNA (siRNA) treatment increased radiosensitivity, whereas FOXM1 overexpression decreased radiosensitivity, and DNA damage was altered significantly under both conditions, as well as the levels of redox-related molecules and reactive oxygen species production. Treatment with the FOXM1 inhibitor thiostrepton had a radiosensitizing effect and overcame radiotolerance in CRR cells. According to these results, the FOXM1-mediated regulation of reactive oxygen species could be a novel therapeutic target for the treatment of radioresistant OSCC; thus, treatment strategies targeting this axis might overcome radioresistance in this disease.

The antioxidative stress regulator Nrf2 potentiates radioresistance of oral squamous cell carcinoma accompanied with metabolic modulation.

Nuclear factor erythroid 2-related factor 2 (Nrf2), which regulates the expression of critical antioxidant proteins, was recently demonstrated to play a key role in cancer progression. Resistance to radiotherapy is a major obstacle in treating oral squamous cell carcinoma (OSCC). However, little is known about the association between Nrf2 and radioresistance in OSCC. Two OSCC cell lines (SAS and HSC-2) and their clinically relevant radioresistant (CRR) clones (SAS-R, HSC-2-R) were used. The effects of Nrf2 downregulation on radiosensitivity and the involvement of glycolysis in Nrf2-mediated radioresistance were evaluated. Immunohistochemistry of phosphorylated Nrf2 (p-Nrf2) was performed in 110 patients with OSCC who underwent preoperative chemoradiotherapy and surgery. Nrf2 was stably upregulated in CRR cells in vitro and in a mouse xenograft model. Moreover, elevated Nrf2 expression was associated with radioresistance. The enhancement of Nrf2-dependent glycolysis and glutathione synthesis was involved in the development of radioresistance. Additionally, p-Nrf2 expression was closely related to the pathological response to chemoradiotherapy, and its expression was predictive of prognosis in patients with advanced OSCC. Our results suggest that Nrf2 plays an important role in the radioresistance of OSCC accompanied by metabolic reprogramming. Targeting Nrf2 antioxidant pathway may represent a promising treatment strategy for highly malignant OSCC.

Role of serum amylase and salivary cytokines in oral complications during chemoradiotherapy.

OBJECTIVES: To investigate whether serum amylase can predict the recovery of salivary volume and determine the correlation of the level of cytokines, including epidermal growth factor, hepatocyte growth factor and keratinocyte growth factor, with oral mucositis during chemoradiotherapy for oral cancer. SUBJECTS AND METHODS: This study included 84 patients treated with preoperative chemoradiotherapy followed by curative surgery, following a phase II study protocol. We measured and analysed the correlation of the stimulated saliva volume, serum amylase and cytokines in resting saliva at baseline and 1 month after chemoradiotherapy with oral mucositis levels. RESULTS: We observed a negative correlation between the serum amylase level at the beginning of chemoradiotherapy and the stimulated saliva volume at 1 month after chemoradiotherapy (p = .03). Epidermal growth factor in resting saliva was significantly reduced after chemoradiotherapy (p < .01). The incidence of severe oral mucositis during chemoradiotherapy was significantly higher and negatively associated with the epidermal growth factor and keratinocyte growth factor levels (p = .04, p = .05). CONCLUSIONS: The serum amylase level at the beginning of chemoradiotherapy may be a predictor of the recovery of the saliva volume. Furthermore, cytokines such as epidermal growth factor and keratinocyte growth factor in resting saliva affect the development of oral mucositis during chemoradiotherapy.

BRD4 promotes metastatic potential in oral squamous cell carcinoma through the epigenetic regulation of the MMP2 gene.

BACKGROUND: Oral squamous cell carcinoma (OSCC) has increased morbidity, and its high metastatic potential affects patient survival. Bromodomain containing 4 (BRD4) is a chromatin protein that associates with acetylated histone lysines and facilitates transcription. BRD4 has been implicated in cell proliferation, metastasis, and prognosis in several types of cancer. However, the role of BRD4 in OSCC remains to be elucidated. METHODS: We investigated the role of BRD4 and its potential utility as a therapeutic target in OSCC. RESULTS: JQ1, the BRD4 inhibitor, suppressed the cell proliferation, migration, and invasion in the OSCC cell lines and in vivo. JQ1 reduced the expression levels of 15 metastasis genes in OSCC, including matrix metallopeptidase 2 (MMP2). Our chromatin immunoprecipitation assay showed that JQ1 reduced the BRD4 binding to the histone H3 lysine 27 acetylation-enriched sites in the MMP2 locus. Analyses of biopsy specimens from OSCC patients revealed that the BRD4 and MMP2 expression levels were correlated in the cancerous regions, and both were highly expressed in lymph node metastasis cases, including delayed metastasis. CONCLUSIONS: BRD4 contributes to metastasis in OSCC, through the epigenetic regulation of the MMP2 gene, and thus BRD4 may represent a therapeutic target and a novel prediction indicator for metastasis.

HMGA2 Contributes to Distant Metastasis and Poor Prognosis by Promoting Angiogenesis in Oral Squamous Cell Carcinoma.

The highly malignant phenotype of oral squamous cell carcinoma (OSCC), including the presence of nodal and distant metastasis, reduces patient survival. High-mobility group A protein 2 (HMGA2) is a non-histone chromatin factor that is involved in advanced malignant phenotypes and poor prognosis in several human cancers. However, its biological role in OSCC remains to be elucidated. The purpose of this study was to determine the clinical significance and role of HMGA2 in the malignant potential of OSCC. We first investigated the expression pattern of HMGA2 and its clinical relevance in 110 OSCC specimens using immunohistochemical staining. In addition, we examined the effects HMGA2 on the regulation of vascular endothelial growth factor (VEGF)-A, VEGF-C, and fibroblast growth factor (FGF)-2, which are related to angiogenesis, in vitro. High expression of HMGA2 was significantly correlated with distant metastasis and poor prognosis. Further, HMGA2 depletion in OSCC cells reduced the expression of angiogenesis genes. In OSCC tissues with high HMGA2 expression, angiogenesis genes were increased and a high proportion of blood vessels was observed. These findings suggest that HMGA2 plays a significant role in the regulation of angiogenesis and might be a potential biomarker to predict distant metastasis and prognosis in OSCC.

FBXW7 expression affects the response to chemoradiotherapy and overall survival among patients with oral squamous cell carcinoma: A single-center retrospective study.

FBXW7 (F-box and WD repeat domain containing-7) is a tumor suppressor protein that regulates the degradation of various oncoproteins in several malignancies. However, limited information is available regarding FBXW7 expression in oral squamous cell carcinoma. Therefore, this study aimed to determine the clinical significance of FBXW7 expression in oral squamous cell carcinoma. The FBXW7 expression patterns in oral squamous cell carcinoma and adjacent normal tissues from 15 patients who underwent radical resection were evaluated using quantitative real-time polymerase chain reaction and immunohistochemical staining. In addition, immunohistochemistry was performed using paraffin-embedded sections from biopsy specimens obtained from 110 patients with oral squamous cell carcinoma who underwent surgery after 5 fluorouracil-based chemoradiotherapy. The associations of FBXW7 expression with various clinicopathological features and prognosis were evaluated in these patients. As a results, in the 15 matched samples, the FBXW7 expression was significantly decreased in the oral squamous cell carcinoma tissues compared to that in the adjacent normal tissues. In the clinicopathological analysis, compared to high protein expression, low FBXW7 expression was found to significantly associate with a poor histological response to preoperative chemoradiotherapy. Kaplan-Meier curve analysis revealed that low FBXW7 expression was significantly associated with a poor prognosis, and FBXW7 expression was found to be an independent predictor of overall survival in the multivariate analysis. Our results suggest that FBXW7 may function as a tumor suppressor protein in oral squamous cell carcinoma. In addition, FBXW7 could be a potential biomarker for predicting not only the clinical response to chemoradiotherapy but also overall survival in patients with oral squamous cell carcinoma.

IL-6 controls resistance to radiation by suppressing oxidative stress via the Nrf2-antioxidant pathway in oral squamous cell carcinoma.

BACKGROUND: In promoting tumour malignancy IL-6 signalling is considered to have an important role. However, the biological roles of IL-6 on radiosensitivity in oral squamous cell carcinoma (OSCC) remain largely unclear. The objective of this study is to determine the effects and molecular mechanisms of IL-6 on radiosensitivity in OSCC. METHODS: Two OSCC cell lines, and OSCC tissue samples with radioresistant cells were used. We examined the effects of IL-6, or tocilizumab, a humanised anti-human IL-6 receptor antibody, or both on radiosensitivity and DNA damage after X-ray irradiation in vitro. In addition, we investigated the involvement of the Nrf2-antioxidant pathway in IL-6-mediated radioresistant mechanisms using OSCC cell lines and tissues. RESULTS: Increased levels of IL-6 suppressed radiation-induced cell death, and the blockade of IL-6 signalling by tocilizumab sensitised tumour cells to radiation. The radioresistant effect of IL-6 was associated with decreased DNA damage after radiation. We also found that IL-6 promotes the activation of not only the downstream molecule STAT3 but also the Nrf2-antioxidant pathway, leading to a significant decrease in oxidative stress by upregulating Mn-SOD. CONCLUSIONS: These results indicate that the blockade of IL-6 signalling combined with conventional radiotherapy could augment the treatment response and survival rate in patients with radioresistant OSCC.

Pre-treatment neutrophil to lymphocyte ratio predicts the chemoradiotherapy outcome and survival in patients with oral squamous cell carcinoma: a retrospective study.

BACKGROUND: The Neutrophil to lymphocyte ratio (NLR) has prognostic value in patients with a variety of cancers. However, its prognostic significance in oral squamous cell carcinoma (OSCC) patients has not been fully explored. The purpose of this study was to determine the clinical significance of NLR in patients with OSCC. METHODS: OSCC patients who underwent surgery following 5-fluorouracil (5-FU)-based chemoradiotherapy were enrolled in this study. The associations between the NLR status and various clinicopathological features were examined, and the effects of the NLR on the prognosis were evaluated. Analysis of circulating interleukin-6 (IL-6) was carried out and correlation with NLR and C-reactive protein concentration (CRP) was examined. RESULTS: An elevated NLR was significantly correlated with advanced T-stage and poor response to chemoradiotherapy. Moreover, a Cox regression analysis based on the disease-free survival (DFS) revealed the NLR status (hazard ratio, 2.013; P = 0.041) and pathological response to chemoradiotherapy (hazard ratio, 0.226; P = 0.001) to be significant prognostic factors in OSCC patients. Furthermore, circulating IL-6 was found to correlate with NLR and CRP. CONCLUSION: The NLR is a potential biomarker for predicting the clinical response to 5-FU-based chemoradiotherapy and the survival in OSCC patients, and the systemic inflammatory response may be potential target for improving patient's prognosis.

Factors associated with antisocial behavior in patients with developmental disorder.

Objective: This study investigated the factors associated with antisocial behavior (AB) in children with developmental disorder and effective treatments. Methods: Participants were 110 schoolchildren with developmental disorder and with or without accompanying AB who visited our hospital between October 2009 and October 2012. Among the children with AB, those who exhibited one or more symptoms of conduct disorder (CD) were assigned to the CD subgroup. We examined the background characteristics, past history, type of antisocial behavior, and symptom improvement after treatment in the children with AB and compared the relevant factors with children with developmental disorder without AB. Results: Of the 110 participants, 72 (65.5%) did not exhibit AB and 38 (34.5%) did, 7 (5.5%) of whom fulfilled the criteria for CD. Compared to the children without AB, the children with AB showed a significantly higher occurrence of attention deficit/hyperactivity disorder (AD/HD), maltreatment, institutionalization due to maltreatment, parental mental/psychological problems, and family instability. After medical treatment combined with social-skills training and parental education, 22 of the 38 children with AB showed improved behavior. In the CD subgroup, 4 children were diagnosed with AD/HD and 3 with pervasive developmental disorder, and none of the 7 improved with treatment. Conclusion: AB was associated with AD/HD, maltreatment, institutionalization, parental mental/psychological problems, and family instability. The most effective therapy was parental education. Children with AB need early intervention given that those who already exhibited symptoms of CD showed little improvement with treatment.

A low Dicer expression is associated with resistance to 5-FU-based chemoradiotherapy and a shorter overall survival in patients with oral squamous cell carcinoma.

BACKGROUND: The deregulation of microRNA (miRNA) is associated with multiple processes involved in cancer progression. RNase III endonucleases, Dicer and Drosha, are key enzymes for miRNA biogenesis, and it has been reported that altered expressions of these molecules affect the clinical outcomes of patients with various cancers. However, the clinical value of measuring the levels of Dicer and Drosha in oral squamous cell carcinoma (OSCC) patients is unclear. The purpose of this study was to determine the clinical significance of the expressions of Dicer and Drosha in patients with OSCC. METHODS: Oral squamous cell carcinoma specimens were obtained from 61 patients who underwent surgery following 5-fluorouracil-based chemoradiotherapy at Kumamoto University Hospital between October 2003 and January 2009. Paraffin-embedded sections obtained from biopsy specimens were immunohistochemically analyzed. The associations between Dicer, Drosha, and various clinicopathological features were examined, and the effects of Dicer and Drosha on the prognosis were evaluated. RESULTS: A low Dicer tumor expression was significantly correlated with the pathological response to chemoradiotherapy. Furthermore, a Cox regression analysis based on the overall survival revealed the Dicer expression status (hazard ratio, 0.34; P = 0.048) and pathological response to chemoradiotherapy (hazard ratio, 0.21; P = 0.014) to be significant prognostic factors in OSCC patients. On the other hand, the Drosha expression was not associated with any clinicopathological features or the prognosis. CONCLUSION: These results suggest that Dicer is a potential biomarker for predicting the clinical response to 5-FU-based chemoradiotherapy and the overall survival in patients with OSCC.

Quality of life of children with neurodevelopmental disorders and their parents during the COVID-19 pandemic: a 1-year follow-up study.

This study aimed to reveal changes in the quality of life (QOL) of children with neurodevelopmental disorders and their parents, and the interaction between their QOL and parental mental state during the coronavirus 2019 (COVID-19) pandemic. Eighty-nine school-aged children and parents participated in surveys in May 2020 (T1) and May 2021 (T2). The parents completed questionnaires that assessed their QOL, depression, parenting stress, and living conditions. Children's temporary mood status was evaluated using the self-reported visual analog scale (VAS). Children's QOL and VAS at T2 were higher than their QOL at T1. Parents' QOL at T2 was lower than their QOL at T1. Severe parental depression at T1 had a synergistic effect on severe parenting stress and severe depressive state at T2. Additionally, children's high QOL at T1 had a synergistic effect on low parenting stress and children's high QOL at T2. Furthermore, children's low VAS scores and parents' low QOL at T2 were associated with deterioration of family economic status. Children and parents' QOL changed during the prolonged COVID-19 pandemic. Improvement in children's QOL was influenced by reduced maternal depressive symptoms. Public support for parental mental health is important to avoid decreasing QOL.

An oncolytic virus as a promising candidate for the treatment of radioresistant oral squamous cell carcinoma.

We evaluated the usefulness of an oncolytic virus (Suratadenoturev; OBP-301) against radioresistant oral squamous cell carcinoma. We confirmed the expression of human telomerase reverse transcriptase and the coxsackievirus and adenovirus receptor in cell lines. Also, we examined the potential presence in a patient who has received existing therapy that is amenable to treatment with OBP-301. We evaluated: (1) the antitumor effects of OBP-301 alone and in combination with radiotherapy on radioresistant cell lines, (2) the molecular mechanism underlying the radiosensitizing effect and cell death increased by the combination therapy, and (3) the antitumor effect of the combination therapy in vivo using xenograft models (a radioresistant cell line-derived xenograft in mouse and a patient-derived xenograft). Human telomerase reverse transcriptase and the coxsackievirus and adenovirus receptor were expressed in all cell lines. OBP-301 decreased the proliferative activity of these cell lines in a concentration-dependent manner, and significantly enhanced the antitumor effect of irradiation. Phosphorylated STAT3 and its downstream molecules, which correlated with apoptosis and autophagy, showed significant changes in expression after treatment with OBP-301. The combination therapy exerted a significant antitumor effect versus radiotherapy alone in both xenograft models. Combination of OBP-301 with radiotherapy exerts a synergistic effect and may represent a promising treatment for radioresistant oral squamous cell carcinoma.

miR-30a attenuates drug sensitivity to 5-FU by modulating cell proliferation possibly by downregulating cyclin E2 in oral squamous cell carcinoma.

We aimed to determine the functional role of the miRNA, which affects drug sensitivity to 5-FU in oral squamous cell carcinoma (OSCC), using two types of 5-FU-resistant and parental OSCC cell lines. MiRNA microarray data showed that miR-30a was significantly upregulated in two resistant cell lines. Therefore, we investigated the effects and molecular mechanism of miR-30a on 5-FU sensitivity. Stable overexpression of miR-30a in parental OSCC cells decreased cell proliferation and attenuated drug sensitivity to 5-FU. Cell cycle analysis indicated that miR-30a overexpression increased the proportion of G1 phase cells and decreased the proportion of S phase cells. MiR-30a knockdown using siRNA reversed the effects of miR-30a overexpression. DNA microarray analysis using miR-30a-overexpressing cell lines and a TargetScan database search showed that cyclin E2 (CCNE2) is a target of miR-30a. A luciferase reporter assay confirmed that a miR-30a mimic interacted with the specific binding site in the 3' UTR of CCNE2. CCNE2 knockdown with siRNA in OSCC cells yielded decreased drug sensitivity to 5-FU, similar to miR-30a overexpressing cells. These findings suggest that miR-30a in OSCC may be a novel biomarker of 5-FU-resistant tumors, as well as a therapeutic target for combating resistance.

Psychological Status Associated With Low Quality of Life in School-Age Children With Neurodevelopmental Disorders During COVID-19 Stay-At-Home Period.

Background: This study seeks to ascertain how the COVID-19 stay-at-home period has affected the quality of life (QOL) of children with neurodevelopmental disorders (NDDs) who had experienced sleep schedules alteration and clarify what psychological status predicted low QOL in children with and without altered sleep patterns. Materials and Methods: Study participants were 86 children between 8 and 17 years of age (mean age, 11.7 years; 70 boys, 16 girls; mean intellectual quotient, 83.6). QOL was evaluated using the self-assessment KINDLR. Participants answered questions regarding depression and anxiety on a visual analog scale (VAS) for temporary mood. Their parents answered questionnaires regarding their maladaptive behaviors and differences in sleep patterns before and during the COVID-19 pandemic. The student's t-test was performed to examine the presence or absence of sleep changes in the children, which affected QOL, temporary mood, and maladaptive behaviors. Multiple or simple linear regression analyses were also performed to identify the psychogenic factors that significantly affected decreased QOL for each group with and without changes in sleep schedule. Results: During the COVID-19 stay-at-home period, 46.5% of participants experienced changes in sleep patterns. These changes were associated with decreased QOL as well as internalized symptoms. The decreased QOL of children with sleep patterns changed was predicted by a high level of depression. In addition, low QOL in children with unchanged sleep patterns was predicted by a high level of depression and low current mood status. Conclusions: Almost half of the participants experienced a poor sleep schedule during the stay-at-home period. These alterations in sleep patterns were associated with a low QOL. The QOL of children with a stable life schedule was affected not only by depressive tendencies but also temporary moods. Therefore, they need to live a fulfilling life to maintain their QOL. However, the QOL of children with poor sleep patterns was affected only by depressive tendencies. Hence, clinicians need to ensure that children with NDDs are well-diagnosed with depression and treated for sleep problems.

The quality of life of children with neurodevelopmental disorders and their parents during the Coronavirus disease 19 emergency in Japan.

This study aimed to reveal how the COVID-19 stay-at-home period has affected the quality of life (QOL) of children with neurodevelopmental disorders and their parents and to identify possible factors that enabled them to maintain their QOL. We enrolled 136 school-aged children (intellectual quotient ≥ 50) and their parents and administered QOL questionnaires to assess the maladaptive behavior of the children; depression, anxiety, and stress of the parents; and activities of their daily lives. The relationship between their QOL and clinical features was examined. The decrease in QOL of children and parents was associated with the mother's limited job flexibility. Decreased QOL was also associated with changes in the sleep rhythms of the children. Maladaptive behaviors in children were associated with parental stress. However, maintained QOL of some families who faced these same conditions of job stress and sleep disorders was associated with less parental stress, less parental depression and anxiety, and milder maladaptive behavior in children. Both mothers with limited job flexibility and changes in the sleep rhythm of children were associated with reduced QOL of children and their parents. Low parental stress was associated with decreased maladaptive behavior in children and with maintained QOL of the family.

Postoperative delirium in patients undergoing tumor resection with reconstructive surgery for oral cancer.

Many attempts have been made to identify the risk factors for postoperative delirium, but this has proved difficult due to its complex morbidity. Furthermore, there is little information on postoperative delirium in patients undergoing tumor resection and reconstructive surgery for oral cancer. The aim of the current study was to investigate the incidence of and risk factors for postoperative delirium in patients undergoing resection and reconstructive surgery for oral cancer. The present study included 104 patients with pedicle or free flap reconstruction. Postoperative delirium developed in 22 (21.2%) of these patients. The mean time to onset of postoperative delirium was 2.5±1.0 days and the duration of delirium was 1.9±1.2 days. Univariate analysis demonstrated that the occurrence of postoperative delirium was significantly correlated with operating time (P=0.033), duration of anesthesia (P=0.039), amount of blood loss (P=0.027), method of reconstruction (P=0.008), type of flap used (P=0.009) and time until postoperative ambulation (P=0.0008). Low postoperative red blood cell count (P=0.004), hemoglobin (P=0.004) and hematocrit (P=0.004) were significantly associated with delirium, but preoperative blood test results were not. The multiple logistic regression analysis of these risk factors revealed that the only significant correlation that remained was between postoperative delirium and the time to ambulation after surgery (P=0.005). Since 2009, the Department of Oral and Maxillofacial Surgery, Kumamoto University Hospital has promoted ambulation after the first two postoperative days for patients with oral cancer undergoing tumor resection with reconstruction, and the occurrence of postoperative delirium has decreased from 29.2 to 14.0%. The results of the current study suggest that early postoperative ambulation in patients who undergo reconstructive surgery for oral cancer is effective for preventing postoperative delirium.

Extracellular vesicles derived from radioresistant oral squamous cell carcinoma cells contribute to the acquisition of radioresistance via the miR-503-3p-BAK axis.

Despite advancements in treatments, oral squamous cell carcinoma (OSCC) has not significantly improved in prognosis or survival rate primarily due to the presence of treatment-resistant OSCC. The intercellular communication between tumour cells is a molecular mechanism involved in acquiring OSCC treatment resistance. Extracellular vesicles (EVs) and encapsulated miRNAs are important mediators of intercellular communication. Here, we focused on EVs released from clinically relevant radioresistant (CRR) OSCC cells. Additionally, we evaluated the correlation between miRNA expression in the serum samples of patients who showed resistance to radiotherapy and in EVs released from CRR OSCC cells. We found that EVs released from CRR OSCC cells conferred radioresistance to radiosensitive OSCC cells via miR-503-3p contained in EVs. This miR-503-3p inhibited BAK and impaired the caspase cascade to suppress radiation-induced apoptosis. Furthermore, OSCC cells with BAK knockdown had increased radioresistance. Additionally, the expression of circulating miR-503-3p in patients with OSCC was correlated with a poor treatment response and prognosis of radiotherapy. Our results provide new insights into the relationship between EVs and the radioresistance of OSCC and suggest that the miR-503-3p-BAK axis may be a therapeutic target and that circulating miR-503-3p is a useful prognostic biomarker in the radiotherapy of OSCC.

Efficacy of adjuvant chemotherapy with S-1 in stage II oral squamous cell carcinoma patients: A comparative study using the propensity score matching method.

It has been reported that 20% of early-stage oral squamous cell carcinoma (OSCC) patients treated with surgery alone (SA) may exhibit postoperative relapse within 2-3 years and have poor prognoses. We aimed to determine the safety of S-1 adjuvant chemotherapy and the potential differences in the disease-free survival (DFS) between patients with T2N0 (stage II) OSCC treated with S-1 adjuvant therapy (S-1) and those treated with SA. This single-center retrospective cohort study was conducted at Kumamoto University, between April 2004 and March 2012, and included 95 patients with stage II OSCC. The overall cohort (OC), and propensity score-matched cohort (PSMC) were analyzed. In the OC, 71 and 24 patients received SA and S-1, respectively. The time to relapse (TTR), DFS, and overall survival were better in the S-1 group, but the difference was not significant. In the PSMC, 20 patients each received SA and S-1. The TTR was significantly lower in the S-1 group than in the SA group, while the DFS was significantly improved in the former. S-1 adjuvant chemotherapy may be more effective than SA in early-stage OSCC.

Onodera's prognostic nutritional index correlates with tumor immune environment and survival in patients with oral squamous cell carcinoma undergoing chemoradiotherapy.

Pretreatment nutritional and immunological status is useful for predicting survival outcomes for various types of malignant tumors. Our objective was to determine the impact of the pretreatment Onodera's prognostic nutritional index (OPNI) on outcomes of patients who underwent definitive chemoradiotherapy for advanced oral squamous cell carcinoma (OSCC). We reviewed 47 patients treated for OSCC with definitive chemoradiotherapy (CRT) at our institution between January 2004 and December 2011. We determined the OPNI according to the following formula: 10 × serum albumin (g/dL) + 0.005 × total lymphocyte count (per µL). We determined the optimum OPNI cut-off through a receiver operating characteristic analysis. We analyzed the associations between OPNI status and various clinicopathological features and evaluated the effects of OPNI on the prognosis. We examined the relationships between OPNI and systemic inflammatory response parameters and analyzed intratumoral CD8+ T cells and their correlation with OPNI. The optimum OPNI cut-off was 42.7. A Kaplan-Meier curve analysis revealed that low OPNI was significantly associated with poor overall survival and cause-specific survival. The multivariate analysis revealed that low OPNI was independently correlated with poor 5 year overall survival and cause-specific survival. OPNI was significantly correlated with systemic inflammatory response parameters. Intratumoral CD8+ T cell counts in primary tumors were significantly lower for low OPNI than for high OPNI. The present data demonstrate that pretreatment OPNI is a valuable independent prognostic indicator of overall and cause-specific survival in advanced OSCC following definitive CRT. OPNI might reflect the tumor immune microenvironment characterization in OSCC.

Enhanced Expression of IGFBP-3 Reduces Radiosensitivity and Is Associated with Poor Prognosis in Oral Squamous Cell Carcinoma.

Insulin-like growth factor (IGF) binding protein-3 (IGFBP-3) modulates various cell functions through IGF-dependent or independent mechanisms. However, its biological roles in the radiosensitivity of oral squamous cell carcinoma (OSCC) remain largely unknown. The purpose of this study was to determine the clinical significance and molecular mechanisms of the association between IGFBP-3 and OSCC radiosensitivity. We performed an immunohistochemical analysis of IGFBP-3 in 52 OSCC specimens from patients treated with preoperative chemoradiotherapy and surgery (phase II study). Associations between IGFBP-3 expression and clinicopathological features were also evaluated. In addition, we examined the effects of IGFBP-3 on post-X-ray irradiation radiosensitivity and DNA damage in vitro. High IGFBP-3 expression was significantly correlated with poor chemoradiotherapy responses and prognosis. With IGFBP-3 knockdown, irradiated OSCC cells exhibited significantly higher radiosensitivity compared with that of control cells. Moreover, IGFBP-3 depletion in OSCC cells reduced phosphorylation of the DNA-dependent protein kinase catalytic subunit (DNA-PKcs), which is required for DNA double-strand break repair during non-homologous end joining. These findings indicate that IGFBP-3 may have a significant role in regulating DNA repair and is be a potential biomarker for predicting clinical response to radiotherapy and prognosis in OSCC.