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Preoperative assessment is essential to prevent inferior alveolar nerve (IAN) injury during surgical extraction of the lower third molar (LM3). Here, we aimed to establish an assessment system to predict IAN injury during surgical extraction of the LM3. We conducted a retrospective cohort study on 115 patients diagnosed as 'high-risk' based on our previous risk assessment method involving three anatomical features of the inferior alveolar canal using computed tomographic (CT) images. We evaluated the occurrence of neurosensory impairment in these high-risk patients, and its association with novel anatomic features based on CT images. Neurosensory impairments were observed in 19 patients (16.5%). The inferior alveolar canal major diameter (p0.0001) and lingual bone thickness (p = 0.0039) were significantly associated with the occurrence of neurosensory impairment during LM3 extraction. Receiver operating characteristic curves were used to determine cut-off values of these quantitative factors to specifically predict IAN injury. Preoperative risk assessment with quantitative factors based on anatomical features observed on CT images may facilitate more appropriate surgical planning for patients at a high risk of IAN injury.

Sepsis is a systemic reaction to an infection and resulting in excessive production of inflammatory cytokines and chemokines. It sometimes results in septic shock. The present study aimed to identify quinolone antibiotics that can reduce tumor necrosis factor alpha (TNFα) production and to elucidate mechanisms underlying inhibition of TNFα production. We identified quinolone antibiotics reduced TNFα production in lipopolysaccharide (LPS)-stimulated THP-1 cells. Sitafloxacin (STFX) is a broad-spectrum antibiotic of the quinolone class. STFX effectively suppressed TNFα production in LPS-stimulated THP-1 cells in a dose-dependent manner and increased extracellular signal-regulated kinase (ERK) phosphorylation. The percentage of intracellular TNFα increased in LPS-stimulated cells with STFX compared with that in LPS-stimulated cells. TNFα converting enzyme (TACE) released TNFα from the cells, and STFX suppressed TACE phosphorylation and activity. To conclude, one of the mechanisms underlying inhibition of TNFα production in LPS-stimulated THP-1 cells treated with STFX is the inhibition of TNFα release from cells via the suppression of TACE phosphorylation and activity. STFX may kill bacteria and suppress inflammation. Therefore, it can be effective for sepsis treatment.

Objective Accumulating evidence has demonstrated the protumor role of estrogen receptor (ER)–mediated signaling in multiple cancer types, which is distinct from this signaling in sex steroid–dependent organs. However, its role in oral squamous cell carcinoma (OSCC) remains unclear. Study Design We assessed the expression of ERα and ERβ in human OSCC tissues by immunohistochemistry and evaluated the expression of both receptors in OSCC cell lines by immunoblotting and flow cytometry. To further assess the contribution of ER-mediated signals to oral cancer progression, proliferation, invasion, and chemosensitivity, cell lines were stimulated with the ER agonist β-estradiol. Results Immunohistochemical analysis of OSCC tissues showed that ERβ was present in the cytoplasm and nuclei of OSCC cells. In contrast, ERα was not detected in any of the cases analyzed. Additionally, the proliferation and invasiveness of OSCC cells were significantly elevated following stimulation with β-estradiol. Chemotherapeutic agent–induced apoptosis of cancer cells was attenuated by pretreatment with β-estradiol. Conclusions ER-mediated signaling plays a crucial role in oral cancer progression by facilitating the proliferation, invasion, and chemoresistance of OSCC cells, indicating its potential for developing novel targeted therapies for this type of cancer.

Although the dosage of oral antibiotics (OA) for the mandibular third molar extraction (MTME) varies among the administration periods according to the current guideline, our previous reports suggested that it might be possible to further shorten the administration period without increasing the incidence of surgical site infection (SSI). In the present study, we retrospectively evaluated the relationship between the incidence of SSI and the administration period of OA in patients who underwent the MTME in our hospital. This retrospective cohort study included 348 patients who underwent the MTME in our dental outpatient clinic from June 2020 to March 2022. The administrated antibiotic was amoxicillin (AMPC) in all patients. Patients were divided into two groups based on the administration period of AMPC single and three times before the surgery. The following information was collected: (1) patient factors (age, gender, body mass index, diagnosis, mandibular third molar status); (2) surgical factors (operation time, presence/absence of wound closure, presence/absence of hemostat, experience of surgeons); (3) relationship between administration period of OA and SSI occurrence; and (4) details of SSI. There were 217 cases in the single group and 131 cases in the three times group. The incidence of SSI was 1.1% (4/348), with 1.4% (3/217) in the single group and 0.8% (1/131) in the three times group; there was no significant difference between the two groups. Our result suggests that single administration of AMPC before the MTME would be sufficient for the prevention of SSI in Japanese patients without risk factors.

The long-term administration of tamoxifen to estrogen receptor α (ERα)-positive breast cancer patients is an established treatment that reduces mortality and recurrence. However, resistance to tamoxifen and an increased risk of endometrial cancer may occur; therefore, the mechanisms by which tamoxifen causes these adverse effects warrant further study. Tamoxifen has been shown to activate mitogen-activated protein kinase (MAPK) in an ERα-independent manner; therefore, we investigated its effects on the MAPK-mediated non-canonical activation of EphA2, a critical event regulating cell migration. Tamoxifen at slightly higher concentrations induced the rapid phosphorylation of EphA2 at Ser-897 via the MAPK/extracellular signal-regulated kinase (ERK) kinase (MEK)-ERK-ribosomal S6 kinases (RSK) pathway in HeLa cells. In addition, tamoxifen significantly enhanced the migration ability of ERα-negative MDA-MB-231 breast cancer cells in RSK- and EphA2-dependent manners. Phosphorylated EphA2 was internalized and re-localized to the plasma membrane, including lamellipodia, in an RSK-dependent manner. Collectively, the present results provide novel insights into the tumor-promoting activity of tamoxifen.

The immune checkpoint inhibitor (ICI) nivolumab has revolutionized the treatment for recurrent or metastatic advanced oral cancer. Because the response rate remains low, the identification of predictive indicators of the response to nivolumab is among the most critical issues. The neutrophil-to-lymphocyte ratio(NLR)is a potential predictive marker of the response to nivolumab in patients with various cancer types. However, the utility of the NLR as a biomarker for predicting the response of oral cancer patients to ICIs is poorly understood.In this retrospective cohort study, we evaluated the association between NLR and nivolumab treatment outcome in 13 patients diagnosed with recurrent or metastatic oral squamous cell carcinoma(OSCC)treated with nivolumab at the Toyama University Hospital between December 2017 and December 2019.Complete response(CR)and partial response(PR)rates of 38.5%(5/13)and 0% (0/13), respectively, were observed in responders; stable disease(SD)and progressive disease(PD)rates of 7.7%(1/13) and 53.8%(7/13), respectively, were observed in non-responders. After nivolumab treatment, the median NLR among responders decreased to 3.3(3.0-3.9)from 4.1(3.7-4.3)during pre-treatment assessment and increased from 5.6(3.2- 9.2)at pre-treatment to 9.4(5.3-17.9)among non-responders. Moreover, patients with higher NLRs(≥5)in the post- treatment group had a significantly worse overall survival than those with lower NLRs(5). Specifically, patients with a higher post-treatment NLR(≥10)had significantly worse outcomes for post-nivolumab salvage chemotherapy.The NLR could be a useful marker for predicting the treatment response to nivolumab or post-nivolumab salvage chemotherapy in OSCC patients.

Along with blood vessels, lymphatic vessels play an important role in the circulation of body fluid and recruitment of immune cells. Postnatal lymphangiogenesis commonly occurs from preexisting lymphatic vessels by sprouting, which is induced by lymphangiogenic factors such as vascular endothelial growth factor C (VEGF-C). However, the key signals and cell types that stimulate pathological lymphangiogenesis, such as human cystic lymphangioma, are less well known. Here, we found that mouse dermal fibroblasts that infiltrate to sponges subcutaneously implanted express VEGF-D and sushi, Von Willebrand factor type A, EGF, and pentraxin domain containing 1 (SVEP1) in response to PDGFRβ signal. In vitro, Pdgfrb knockout (β-KO) fibroblasts had reduced expression of VEGF-D and SVEP1 and overproduced Amphiregulin. Dysregulation of these three factors was involved in the cyst-like and uneven distribution of lymphatic vessels observed in the β-KO mice. Similarly, in human cystic lymphangioma, which is one of the intractable diseases and mostly occurs in childhood, fibroblasts surrounding cystic lymphatics highly expressed Amphiregulin. Moreover, fibroblast-derived Amphiregulin could induce the expression of Amphiregulin in lymphatic endothelial cells. The dual source of Amphiregulin activated EGFR expressed on the lymphatic endothelial cells. This exacerbation cascade induced proliferation of lymphatic endothelial cells to form cystic lymphangioma. Ultimately, excessive Amphiregulin produced by fibroblasts surrounding lymphatics and by lymphatic endothelial cells per se results in pathogenesis of cystic lymphangioma and will be a fascinating therapeutic target of cystic lymphangioma.

The repurposing of existing FDA-approved non-cancer drugs is a potential source of new treatment options for cancer patients. An anti-inflammatory drug, 5-aminosalicylic acid (5-ASA), has been clinically used to treat inflammatory bowel disease. Hyperthermia (HT) is widely applicable addendum therapy with the existing cancer treatment modalities. Here, we addressed how 5-ASA combined with HT induces lethal effects in human oral squamous cell carcinoma (OSCC) HSC-3 cells. We found that 5-ASA/HT combination significantly inhibited the viability of HSC-3 cells, while cytotoxic effects in primary human dermal fibroblast cells were minor. Apoptotic endpoints were significantly increased by the 5-ASA/HT combined treatment, as evidenced by presence of Annexin V-FITC/PI positive cells, loss of MMP, Bcl-2/Bax ratio alteration, and increased Fas, cleaved Bid, and caspase expression. Interestingly, the enhancement of apoptosis was reversed in the presence of ON/ONOO− scavengers. These findings indicate that the combination treatment enhances apoptosis via ON/ONOO− mediated ER stress-Ca2+-mitochondria signaling and caspase-dependent apoptotic pathways. Our findings provide novel evidence that the combination of 5-ASA and HT is a promising approach for the enhancement of apoptosis; it may serve as an effective strategy for treating human OSCC.

Cleft lip and cleft alveolus are caused by incomplete fusion of the frontonasal and maxillary prominences. However, milder forms of cleft lip are rarely accompanied by cleft alveolus. Here, we report a rare case of mini‐microform cleft lip with complete cleft alveolus and cleft palate. No findings suggestive of cleft lip were evident on initial examination. However, three‐dimensional facial measurements confirmed the presence of cleft lip despite no evidence of orbicularis oris muscle (OOM) rupture on ultrasonography. Collapsed nostril, as observed in this case, is usually associated with OOM rupture. However, it can also be caused by skeletal abnormalities, such as cleft alveolus. Three‐dimensional facial measurements and ultrasonography can assist in accurate diagnosis when visual examination is ambiguous.

A retrospective cohort study was performed to assess the clinical usefulness of combination assessment using computed tomography (CT) images in patients undergoing third molar extraction. This study included 85 patients (124 extraction sites). The relationship between cortication status, buccolingual position, and shape of the inferior alveolar canal (IAC) on CT images and the incidence of inferior alveolar nerve (IAN) injury after third molar extraction was evaluated. IAN injury was observed at eight of the 124 sites (6.5%), and in five of 19 sites (26.3%) in which cortication was absent+the IAC had a lingual position+the IAC had a dumbbell shape. Significant relationships were found between IAN injury and the three IAC factors (cortication status, IAC position, and IAC shape; P=0.0001). In patients with the three IAC factors, logistic regression analysis indicated a strong association between these factors and IAN injury (P=0.007). An absence of cortication, a lingually positioned IAC, and a dumbbell-shaped IAC are considered to indicate a high risk of IAN injury according to the logistic regression analysis (P=0.007). These results suggest that a combined assessment of these three IAC factors could be useful for the improved prediction of IAN injury.

Cold atmospheric plasmas (CAPs) have been proposed as a novel therapeutic method for its anti-cancer potential. However, its biological effects in combination with other physical modalities remain elusive. Therefore, this study examined the effects of cold atmospheric helium plasma (He-CAP) in combination with hyperthermia (HT) 42 °C or radiation 5 Gy. Synergistic enhancement in the cell death with HT and an additive enhancement with radiation were observed following He-CAP treatment. The synergistic effects were accompanied by increased intracellular reactive oxygen species (ROS) production. Hydrogen peroxide (H2O2) and superoxide (O2•–) generation was increased immediately after He-CAP treatment, but fails to initiate cell death process. Interestingly, at late hour’s He-CAP-induced O2•– generation subsides, however the combined treatment showed sustained increased intracellular O2•– level, and enhanced cell death than either treatment alone. He-CAP caused marked induction of ROS in the aqueous medium, but He-CAP-induced ROS seems insufficient or not completely incorporated intra-cellularly to activate cell death machinery. The observed synergistic effects were due to the HT effects on membrane fluidity which facilitate the incorporation of He-CAP-induced ROS into the cells, thus results in the enhanced cancer cell death following combined treatment. These findings would be helpful when establishing a therapeutic strategy for CAP in combination with HT or radiation.

The effect of resveratrol on various human cancer cells was investigated with special focus on apoptotic cell death, in an attempt to further characterize its mechanism of action. There were great differences in the anti-viability effect of resveratrol between different types of human cancer cells. While the inhibition of cell viability by resveratrol was marked in U937 and MOLT-4 leukemia cells, resveratrol moderately inhibited cell viability in MCF-7 breast, HepG2 liver, and A549 lung cancer cells, and the effect was slight on cell viability in Caco-2, HCT116, and SW480 colon cancer cells. Following resveratrol treatment, U937 and MOLT-4 markedly increased the population of late apoptotic cells but MCF-7 and HepG2 underwent apoptosis with an increased population of early apoptosis, and resveratrol-induced DNA fragmentation was observed only in leukemic cells. Activation of sirtuin 1 and adenosine-monophosphate-activated protein kinase was not responsible for resveratrol-induced cancer cell death. Instead, resveratrol significantly reduced Akt activation with the downregulation of H-Ras, resulting in facilitation of Bax translocation to mitochondria in leukemic cells. This study suggests that resveratrol can induce apoptotic cell death in human leukemic cells to a greater extent than in human solid tumor cells via reducing Akt activation due to Ras downregulation.

Objectives Aging has been suggested to be associated with immune dysregulation. An understanding of alterations in the host immunity with advancing age is, therefore, important for designing immune therapy for elderly cancer patients. In this context, not much is known about age-associated alterations in the immune system in oral cancer. Methods To evaluate age-associated alterations in the immune system, which might affect anti-tumor immune responses in oral cancer, we performed a comparative analysis of the proportion of different immune cells, the proliferative capacity of T cell compartment, and the response against immune therapies targeting immune check point molecules between young and aged oral cancer-bearing mice. Results The proportion of immune regulatory cells, such as regulatory T cells and myeloid derived suppressor cells, was significantly increased in aged mice compared to that in young mice. Moreover, the expression of PD-1 and CTLA-4 on both CD4+ and CD8+ T cells was elevated in aged mice compared to that in young mice, and the proliferative abilities of CD4+ and CD8+ T cells derived from aged mice were significantly reduced following stimulation of T-cell receptors. Moreover, tumor growth was significantly enhanced in aged mice compared to that in young mice. However, immunotherapies targeting PD-1, CTLA-4, and PD-L1 resulted in faster tumor regression in aged mice than in young mice. Conclusions Together, our results indicate that age-associated alterations in the immune system are directly associated with the impairment of anti-tumor immunity in aged mice bearing oral cancer, and might facilitate the progression of the tumor.

Objective Recent studies have demonstrated the pro-tumour role of CD36 in multiple cancer types. However, its role has not been well elucidated in oral squamous cell carcinoma (OSCC). Here, we aimed to evaluate the role of CD36 in proliferation and migration of OSCC cells. Methods Human OSCC cell lines HSC-2, HSC-3, HSC-4 and Ca9-22 were assessed for proliferation by staining with the cell proliferation marker Ki-67. We also assessed migration activity, and the expression of cell adhesion molecules such as E-cadherin and β-catenin and platelet-derived growth factor receptors (PDGFRs) of CD36-positive cells. Results CD36-positive cells showed increased expression of Ki-67 and migration activity compared with CD36-negative cells. Moreover, CD36-positive cells showed reduced expression of E-cadherin and β-catenin, whereas the expression of PDGFRs increased compared with that in CD36-negative cells. Conclusions Our results strongly suggest that CD36 has an important role in facilitating the proliferation and migration activity of OSCC cells, indicating its usefulness in the diagnosis of high-grade tumour and targeted therapy of oral cancer.

Dyskeratosis congenita (DC) is an inherited disease characterized by the triad of skin pigmentation, nail dystrophy, and oral leukoplakia. Among other abnormalities, bone marrow failure and a predisposition to cancer are recognized as the major causes of premature mortality in patients with DC. This disease is associated with short telomeres and mutations in 10 genes associated with telomerase and telomere components. The case of a 35-year-old male patient diagnosed with DC, who presented with leukoplakia of the tongue and had a high degree of hypoplastic marrow, but no haematological abnormalities, is reported here. The diagnosis of DC was confirmed by detection of short telomeres in the blood cells and mutations in the DKC1 gene. This encounter with the case presented suggests that an awareness of the classical forms of DC is important for oral clinicians so that an early diagnosis can be made and the patient can be managed appropriately. Furthermore, genetic analysis is necessary to establish the diagnosis of DC.

Sulfasalazine (SSZ) is a well-known anti-inflammatory drug and also an inhibitor of the cystine-glutamate antiporter that is known to reduce intracellular glutathione (GSH) level and increase cellular oxidative stress, indicating its anti-tumor potential. However, the combination of SSZ with other physical modalities remains unexplored. Here, the effects of SSZ on cold atmospheric helium plasma (He-CAP), which produces approximately 24 x higher concentration of hydroxyl radicals (. OH) compared to X-irradiation (IR) in aqueous solution, and on IR-induced apoptosis in human leukemia Molt-4 cells were studied to elucidate the mechanism of apoptosis enhancement. Both the Annexin V-FITC/PI and DNA fragmentation assay revealed that pre-treatment of cells with SSZ significantly enhanced He-CAP and IR-induced apoptosis. Similar enhancement was observed during the loss of mitochondrial membrane potential, intracellular Ca2+ ions, and mitochondria- and endoplasmic reticulum-related proteins. The concentration of intracellular reactive oxygen species (ROS) was much higher in He-CAP treated cells than in X-irradiated cells. On the other hand, strong enhancement of Fas expression and caspase-8 and -3 activities were only observed in X-irradiated cells. It might be possible that the higher concentration of intracellular and extracellular ROS suppressed caspase activities and Fas expression in He-CAP-treated cells. Notably, pretreating the cells with an antioxidant N-acetyl-L-cysteine (NAC) dramatically decreased apoptosis in cells treated by He-CAP, but not by IR. These results suggest that IR-induced apoptosis is due to specific and effective ROS distribution since intracellular ROS formation is marginal and the high production of ROS inside and outside of cells plays unique roles in He-CAP induced apoptosis. We conclude that our data provides efficacy and mechanistic insights for SSZ, which might be helpful for establishing SSZ as a future sensitizer in He-CAP or IR therapy for cancer.

The growth of maxillary bone and the development of dentition are often impaired in patients who have had pushback operations for repair of a cleft palate. There has been considerable discussion about the most suitable technique or material used in such repairs to resolve the problem. Hyperdry amniotic membrane, a new preservable material derived from human amnion, has recently been introduced in several procedures. We have evaluated its use during pushback surgery in animal studies to try to correct the inhibition of growth and development of the maxilla. Mucosal defects were created in 3-week-old rats, and then covered with hyperdry amniotic membrane or not. Healing was assessed by histological and morphological examination at 1 week and 7 weeks postoperatively. In the group treated with hyperdry amniotic membrane, submucosal tissue was reconstructed successfully during the early postoperative period. Lateral palatal growth was not inhibited as much, and medial inclination of the teeth was less, after a period of growth using this material. The results suggest that hyperdry amniotic membrane is a suitable new dressing material for use in the treatment of cleft palate.

Background Osteosarcoma, the most common primary bone malignancy, has an extremely poor prognosis and a high rate of local recurrence and distal metastases. Because osteosarcomas of the head and neck region are rare, accounting for less than 10% of all osteosarcoma cases, limited information is available about their treatment and prognosis. Because of the high rate of distal metastases associated with extragnathic osteosarcoma, surgery combined with chemotherapy is currently considered essential in its treatment. However, the role of chemotherapy has not been well elucidated in the treatment of head and neck osteosarcoma because of the rarity of this condition. Case presentation In this report, we present the case of a 58-year-old Japanese woman with osteosarcoma of the mandible that was treated with radical surgery combined with neoadjuvant and adjuvant chemotherapy. Because the tumor showed rapid growth during neoadjuvant chemotherapy, neoadjuvant chemotherapy was suspended and surgical resection was performed, followed by adjuvant chemotherapy. No evidence of local recurrence and distal metastasis was found 14 months after initial treatment. Local control is considered a principal prognostic factor for head and neck osteosarcoma. Conclusions Wide surgical excision should be considered a primary goal even during neoadjuvant chemotherapy, especially in cases that respond poorly to neoadjuvant chemotherapy.

Papillary cystadenocarcinoma (PCAC) of the salivary gland is a rare malignant tumour and occurs in major and minor salivary glands. PCAC of the mandible is exceptionally rare; only 2 cases have been reported. In this study, the authors report a case of PCAC within the mandible. The patient presented with a painful right mandibular mass that had gradually increased in size. The lesion appeared radiographically as a well-demarcated multilocular radiolucent area, similar to an odontogenic cystic lesion. The authors present a case of PCAC with reference to the relevant literature.

Background Salivary duct carcinoma (SDC) is a high-grade salivary gland malignancy that is associated with an aggressive clinical behavior and poor prognosis. Herein, we report on a long surviving case of SDC of the minor salivary gland with multiple lymph node metastases (LNMs). Case presentation An 83-year-old woman presented with a history of lymphadenopathy in the right side of the neck and recent onset and rapid growth of a mass in the right buccal region. Clinical examinations and biopsy findings were suggestive of a salivary gland malignant tumor with regional LNMs. The patient was treated with neoadjuvant chemotherapy. Tumor excision and ipsilateral radical neck dissection were performed, followed by adjuvant chemoradiotherapy. Postoperative histological examination revealed a tumor with irregular nests of atypical ductal epithelial cells, a cribriform growth pattern, and comedo-like central necrosis that lead to a final diagnosis of SDC. LNMs were observed in six lymph nodes of the right side of the neck. The patient underwent postoperative chemotherapy using single-agent cisplatin that was administered concurrently with radiotherapy (total, 65 Gy). There was no evidence of local recurrence or distant metastasis for >6 years. Conclusions Although available data on treatment modalities for SDC remain limited, multimodal therapy may contribute to improved clinical outcomes in patients with advanced intraoral SDC.

Objective Bisphosphonate-related osteonecrosis of the jaw is a common complication with defective wound healing of oral mucosa and frequently occurs in patients receiving zoledronic acid (ZA). The aim of this in vitro study was to investigate whether ZA has a cytotoxic effect at clinically relevant concentrations on epithelial cells when calcium conditions are altered. Methods HaCaT human keratinocyte cells were treated with ZA in the presence of various concentrations of calcium. The concentrations of ZA included submicromolar ones, which are comparable with those found in the plasma of patients. Cell viability and apoptosis were assessed using MTT assay and annexin V flow cytometry. Results Under standard culture conditions, cell growth was inhibited at 1 μM of ZA or above, but was unaffected by lower concentrations. However, when calcium concentrations were moderately increased, cell viability was decreased and apoptosis was induced at 0.2–0.3 μM of ZA. Moreover, a 50% reduction in serum in the hypercalcemic medium resulted in a significant decrease in cell viability at a much lower concentration (0.05 μM). Conclusion These results suggest that clinically relevant concentrations of ZA, which alone have little effects, can be toxic to the epithelial cells depending on the conditions of extracellular calcium.

Background. Secondary cancers are severe complications in patients who have had allogeneic bone marrow transplantation for childhood leukemia. We describe here a case of squamous cell carcinoma (SCC) of the buccal mucosa in a young adult patient who had had allogeneic bone marrow transplantation for childhood acute leukemia. Methods and Results. The primary tumor was treated with interstitial brachytherapy, and lymph node metastasis was treated by supraomohyoid neck dissection. The patient had a history of acute lymphoblastic leukemia (ALL) at 11 years of age and had received an allogeneic bone marrow transplant from a female donor. Further investigation of the tissue specimens by fluorescent in situ hybridization (FISH) revealed that an XX chromosome pattern was dominant in the tumor region, and this suggested that donor-derived cells might affect carcinogenesis in the recipient. Conclusions. This case presents an incidence of secondary oral cancer associated with allogeneic bone marrow transplantation. © 2008 Wiley Periodicals, Inc. Head Neck, 2009

Purpose To predict the relationship between lower third molars and the inferior alveolar canal (IAC) from panoramic radiographs, and to establish criteria for using computed tomography (CT). Materials and Methods A retrospective cohort study was performed involving 443 patients (695 teeth). Predictor variables were the distance between the third molar and the IAC, and findings according to the Rood's criteria. Outcome variables were the absence of cortication between the third molar and the IAC on the CT image, and injury of the inferior alveolar nerve (IAN). Statistical analysis was performed to assess the relationship between predictor and outcome variables. Results All patients had preoperative panoramic radiographs, and 71 patients (119 teeth) also had CT images. On CT examination, 48 teeth (40.3%) showed absence of cortication. Injury of the IAN was reported in 7 cases (1.0%), 5 of which exhibited absence of cortication; the remaining 2 did not have CT scans. Five of the 48 cases showing absence of cortication exhibited IAN injury, and none of the cases with cortication exhibited IAN injury. On the panoramic images, the following signs were strongly correlated with absence of cortication: a superimposed relationship between the third molar and the IAC; darkness of the root; and diversion and narrowing of the IAC. Conclusion Presence of Rood's criteria was a predictor for a contact relationship between the third molar and the IAC, and an indication for CT examination. However, a superimposed relationship and the absence of Rood's criteria did not necessarily signify a separate relationship between third molar and the IAC.

In this study, we present evidence that gene transfer of the CD40-ligand (CD154) into human immature dendritic cells (DC) imparts direct antitumor effects on tumor cells. DC infected with adenovirus directed to express human CD154 on the cell surface (CD154-DC) elicited significantly higher levels of immune accessory molecules commonly found on mature DC. We found that co-cultivation with a human squamous cell carcinoma cell line (OSC-70) with CD154-DC significantly inhibited cell growth. We further demonstrate that OSC-70 cells stimulated with CD154-DC were more susceptible to apoptosis via TNF-related apoptosis inducing ligand (TRAIL). Importantly, tumor cells co-cultured with CD154-DC in transwell plates expressed upregulated cell surface TRAIL-R2. CD154-DC produced higher levels of interferon (IFN)-gamma, IL-12p70 and soluble CD154, but the ability of CD154-DC to inhibit tumor cell growth was significantly abrogated by a neutralizing antibody to IFN-gamma, indicating that this was mainly mediated by IFN-gamma. Furthermore, intratumoral injection of CD154-DC significantly suppressed OSC-70 tumor growth in a xenograft model. Overall, these results reveal that CD154-DC have potential as an anti-cancer therapy by producing IFN-gamma to arrest adjacent tumor cell growth and increase the susceptibility of apoptosis via TRAIL.

CD154 (CD40-ligand) is a critical transmembrane molecule with potent immune-stimulatory properties that is used in clinical applications of gene therapy for leukemia and lymphoma. However, CD154 is cleaved into a soluble form, and high levels of sCD154 contribute to systemic inflammatory and cardiovascular diseases, suggesting a deleterious side effect of CD154 gene therapy. In this study, we engineered noncleavable mutants of human CD154 with point mutations to develop a potentially less toxic molecule in vivo. In contrast to wild-type CD154 (CD154-WT) subsequently released as sCD154, both mutants CD154-M3 and CD154-M4 were resistant to cleavage in tumor cells. Also, CD40-expressing leukemia B cells transfected with CD154-M3 mutant were highly effective stimulators in a mixed lymphocyte-leukemia reaction, indicating that CD154-M3 mutant did not lose biologic activity. In mice transplanted with tumors expressing CD154-WT, we found increased plasma levels of human sCD154 followed by various systemic inflammatory reactions such as glomerulonephritis and an increased number of infiltrating mononuclear cells in the liver. However, CD154-M3 mutant did not induce any systemic inflammatory effects in vivo. As such, the noncleavable mutant of CD154 is fully capable of inducing the immune response with less toxic properties and is a useful tool for CD154 immune gene therapy.

Background Invasive micropapillary salivary duct carcinoma (SDC) is a rare variant of SDC. Although several cases involving major salivary glands have been reported, no cases arising de novo in minor salivary glands have been reported to date. Here we report the first case of invasive micropapillary SDC that arose in a minor salivary gland of the parapharyngeal space. Methods A 72-year-old male patient presented with an enlarging mass in the left parapharyngeal region along with trismus and swollen lymph nodes. Clinical examinations and biopsy findings were suggestive of a salivary gland malignant tumor with regional lymph node metastases. The tumor, therefore, was excised with partial mandibulectomy with unilateral radical neck dissection. Results Histologically, the tumor consisted of an invasive micropapillary growth pattern of SDC and mixed with mucinous component of SDC. Local recurrence and lung metastasis developed, and the patient died of disease 13 months after the initial treatment. Conclusions We describe the clinical and histologic features of this extremely rare case of minor salivary gland SDC that was histologically characterized by the presence of both invasive micropapillary growth pattern and mucinous component.

Direct antitumor effects of bisphosphonates (BPs) have been demonstrated in various cancer cells in vitro. However, the effective concentrations of BPs are typically much higher than their clinically relevant concentrations. Oral cancers frequently invade jawbone and may lead to the release of Ca(2+) in primary lesions. We investigated the effects of the combined application of zoledronic acid (ZA) and Ca(2+) on proliferation and apoptosis of oral cancer cells. Human oral cancer cells, breast cancer cells, and colon cancer cells were treated with ZA at a wide range of concentrations in different Ca(2+) concentration environments. Under a standard Ca(2+) concentration (0.6mM), micromolar concentrations of ZA were required to inhibit oral cancer cell proliferation. Increasing extracellular Ca(2+) concentrations greatly enhanced the potency of the ZA cytocidal effect. The ability of Ca(2+) to enhance the cytocidal effects of ZA was negated by the Ca(2+)-selective chelator EGTA. In contrast, the cytocidal effect of ZA was less pronounced in breast and colon cancer cells regardless of whether extracellular Ca(2+) was elevated. In oral cancer cells incubated with 1.6mM Ca(2+), ZA up-regulated mitochondrial Bax expression and increased mitochondrial Ca(2+) uptake. This was associated with decreased mitochondrial membrane potential and increased release of cytochrome c. We suggest that ZA can specifically produce potent cytocidal activity in oral cancer cells in an extracellular Ca(2+)-dependent manner, implying that BPs may be useful for treatment of oral squamous cell carcinoma with jawbone invasion leading to the hypercalcemic state.

Purpose: A major problem when using the adenoviral vectors for gene therapy applications is thought to be related to low transduction efficiency in cancer cells or to side effects in normal cells. There is an urgent requirement to improve the specificity of gene delivery in the context of cancer gene therapy.Experimental Design: We constructed a genetically modified adenovirus incorporating an IgG Fc-binding motif from the Staphylococcus protein A, Z33, within the HI loop (Adv-FZ33). A remarkable degree of targeted gene delivery to gastric cancer cells was obtained with Adv-FZ33 with the fully human anti–carcinoembryonic antigen (CEA) monoclonal antibody, C2-45.Results: In vitro LacZ or EGFP gene expression after Adv-FZ33 infection via C2-45 was 20 times higher than control monoclonal antibody in MKN-45 at 1,000 viral particles/cell. We generated Ax3CAUP-FZ33 (UP-FZ33), which is an Adv-FZ33 derivative vector expressing a therapeutic gene (i.e., Escherichia coli uracil phosphoribosyltransferase), which converts 5-fluorouracil (5-FU) directly to 5-fluoro-UMP. UP-FZ33 with C2-45 enhanced the cytotoxicity of 5-FU by 10.5-fold in terms of IC50 against MKN-45 compared with control IgG4. In a nude mouse peritoneal dissemination model, tumor growth in mice treated with UP-FZ33/C2-45/5-FU was significantly suppressed, and tumor volumes were less than one-fourth of those of the control IgG4 group (P < 0.05). The median survival time of the UP-FZ33/C2-45/5-FU group was significantly longer than those treated with PBS or 5-FU only (P < 0.01).Conclusions: These data suggest that CEA-targeted FZ33 mutant adenovirus-mediated gene delivery offers a strong and selective therapeutic modality against CEA-producing cancers.

Salivary duct carcinoma (SDC) is an uncommon neoplasm that most commonly occurs in major salivary glands, mainly the parotid gland. SDC is rarely found in the minor salivary glands of the oral cavity. This report presents an extremely rare case of sarcomatoid SDC originating in a minor salivary gland of the palate. The tumor was histologically characterized by the presence of both carcinomatous and sarcomatoid components. The patient presented with a painless mass in the right palate, which slowly increased in size over 20 years. The clinical course of the present case suggests that the tumor most probably developed as a result of malignant transformation of a preexisting benign tumor of the palatal salivary gland. This report describes the clinical and histologic features of this extremely rare case of sarcomatoid SDC with reference to the relevant literature.

Increasing evidence has revealed the incidence of cancer augments with aging, which could be attributed to a multitude of age-associated changes including the dysregulation of the immune system. Although many reports demonstrate the efficacy of cancer immunotherapies in numerous preclinical studies, most experiments have been performed in young animals. Studies from our group and others show that cancer immunotherapy could be ineffective in old mice, even though the same therapeutic treatment works efficiently in young mice. Given that cancer occurs mostly in the elderly, we should take age-associated immune dysregulation into consideration to achieve the effectiveness of immunotherapeutic interventions in the old. Understanding both age-related and tumor-related immune alterations might be equally important in improving the effectiveness of immunotherapy. This article reviews a number of age-associated immune alterations with specific attention given to the impact on antitumor responses, and also discusses possible strategies for optimization of immunotherapeutic interventions in the elderly.

Summary Background Cancer may be derived from cancer stem-like cells (CSCs), which are tumor-initiating cells that have properties similar to those of stem cells. Identification and isolation of CSCs needs to be improved further. Materials and methods CSCs markers were examined in human oral cancer cell lines by flow cytometry. The stem cell properties of subpopulations expressing different markers were assessed further by in vitro sphere formation assays, expression of stemness genes, drug resistance assays, and the ability to form tumors in nude mice. Results We demonstrated that CSCs could be isolated by the cell surface markers CD44 and stage-specific embryonic antigen-4 (SSEA-4). CD44+SSEA-4+ cells exhibited cancer stem-like properties, including extensive self-renewal into the bulk of cancer cells. In vivo xenograft experiments indicated that CD44+SSEA-4+ cells exhibit the highest tumorigenic capacity compared with the remaining subpopulations and parental cells. Double-positive cells for CD44 and SSEA-4 exhibited preferential expression of some stemness genes and were more resistant to the anticancer drugs, cisplatin and 5-fluorouracil (5-FU). In addition, cells expressing CD44 and SSEA-4 were detected in all tumor specimens analyzed, while coexpression of CD44 and SSEA-4 was not detectable in normal oral mucosa. Conclusion Our findings suggest that CD44+SSEA-4+ cells exhibit the characteristics of CSCs in oral squamous cell carcinoma and provide a target for the development of more effective therapies.

We examined the clinical features of bisphosphonate(BP)-related osteonecrosis of the jaws(BRONJ), a serious complication resulting from intravenous BP treatment for multiple myeloma and malignant tumors with bone metastasis. We retrospectively reviewed the medical records of 36 patients who received intravenous BP therapy for the above-mentioned conditions, at Sapporo Medical University Hospital between July 2006 and October 2008. BP therapy caused BRONJ in 7 of 24 patients, but did not affect the bones of the other 17 patients. The other 12 of the 36 patients involved in the study were prescribed BP only after they had undergone an oral examination and treatment for dental inflammation. Of these patients, 7 developed BRONJ with BP treatment, after tooth extraction or acute dental inflammation. Treating dental inflammation before prescribing BP prevented the development of BRONJ. BRONJ is highly intractable and does not resolve with the standard treatment for osteomyelitis. Therefore, preventive therapy, which can be achieved by cooperation between medical doctors and dentists, is currently the most effective strategy for BRONJ. Conservative treatment with antibiotics may also be useful for maintaining or improving the quality of life of BRONJ patients.

Sendai virus vector is emerging as a promising vector for gene therapy, and angiopoietin-1 (Ang-1) has been reported to improve the blood flow recovery in the ischemic limb or heart. In this study, we constructed a human Ang-1-expressing Sendai viral vector (SeVhAng-1) and injected it into the ischemic limb of rats. We found that SeVhAng-1 improved the blood flow recovery and increased the capillary density of the ischemic limb, compared with the controls. We also found that SeVhAng-1 increased p-Akt during the early period of limb ischemia, and decreased apoptosis in ischemic limb. It suggests that SeVhAng-1 may serve as a potential therapeutic tool in ischemic limb disease.

Osteonecrosis of the jaw is a severe new complication in cancer patients with bone metastases receiving bisphosphonate. Currently, there is no effective treatment for bisphosphonate-related osteonecrosis of the jaw, and the pathogenesis of this complication has not been completely elucidated. It has been shown that a potential risk factor for the complication is dentoalveolar trauma including extraction of teeth during bisphosphonate therapy. Attention should be paid to dental care in patients prior to the initiation of bisphosphonate therapy, and extraction of teeth during bisphosphonate therapy should be avoided to prevent this complication. Therefore, the communication between general physicians prescribing bisphosphonate and dentists is important.

Summary The purpose of this clinical trial was to assess the toxicity and efficacy of docetaxel plus nedaplatin induction chemotherapy in patients with locally advanced oral squamous cell carcinoma (OSCC). Twenty-one patients were enrolled in this phase I/II clinical study. The toxicities, response rates, and the maximum tolerated dose of nedaplatin that could be safely given preoperatively were assessed. Patients received escalating doses of nedaplatin (60, 70, 80, 90 mg/m 2 ) combined with a fixed dose of docetaxel (60 mg/m 2 ) on day one. Dose-limiting toxicity (DLT), grade 4 leukopenia lasting for two days or more, was seen in one patient at dose level 3; no other DLT was observed at any dose level. The overall response rate was 66.7%. The response rate was 100% at nedaplatin dose level 4, while that at dose level 1 was low (33.3%). Given these results, the recommended dose of nedaplatin in this regimen combined with fixed dose docetaxel (60 mg/m 2 ) was determined to be 90 mg/m 2 . Docetaxel 60 mg/m 2 plus nedaplatin 90 mg/m 2 induction chemotherapy can be recommended for patients with locally advanced oral squamous cell carcinoma. Based on these results, an early phase II clinical study using this dose level was conducted; docetaxel plus nedaplatin induction chemotherapy appears to be a useful regimen for the treatment of OSCC. A late phase II clinical study is warranted.

The CD40-ligand (CD40L) is a key molecule for the activation of dendritic cells (DCs), followed by the induction of DC maturation and cytokine production. Here we found that DC infected with adenovirus vector encoding human CD40L (CD40L-DC) displayed significantly higher levels of immune accessory molecules and IL-12 production than did uninfected cells, and that CD40L-DC produced much higher levels of IFN-gamma. To investigate whether CD40L-DC-derived these soluble factors could stimulate NK cells without physical cell-to-cell contact, we cocultured NK cells with CD40L-DC in transwell culture plates. NK cells showed up-regulated cytotoxic activity toward various squamous oral cell carcinoma (OSC-70, HSC-2, HSC-3), and we determined that both IL-12 and IFN-gamma contributed to the CD40L-DC-mediated NK cell activation. NK cells stimulated with CD40L-DC resulted in the induction of the cell surface expression of TRAIL, the production of IFN-gamma and intracellular accumulation of granzyme B. The cytotoxic activity of NK cells stimulated with CD40L-DC could be mostly inhibited by neutralizing antibody for TRAIL and completely abrogated by the combination of antibody and exocytosis inhibitor, indicating that this was mainly mediated by a TRAIL-TRAIL-receptor interaction and granule exocytosis. Moreover, CD40L-DC-activated NK cells could induce up-regulation of a death-receptor TRAIL-R2 (DR5) and down-regulation of a decoy receptor TRAIL-R3 (DcR1) on carcinoma cells. Overall, these results have revealed that CD40L-DC could activate an innate immune reaction by stimulating NK cells followed by carcinoma cells, supporting that administration of CD40L-DC may have potential as an anticancer therapy.