Neuropilin-2 acts a critical determinant for epithelial-to-mesenchymal transition and aggressive behaviors of human head and neck cancer

PURPOSE

Neuropilin-2 (NRP2) is a multifunctional single-pass transmembrane receptor that binds to two disparate ligands, namely, vascular endothelial growth factors (VEGFs) and semaphorins (SEMAs). It is reportedly involved in neuronal and vascular development. In this study, we uncovered the exact functional role of NRP2 and its molecular mechanism during aggressive behaviors and lymph node (LN) metastasis in human head and neck cancer (HNC) and identified algal methanol extract as a potential novel NRP2 inhibitor.

METHODS

In silico analyses and immunohistochemistry were used to investigate the relationship between NRP2 expression and the prognosis of HNC patients. The functional role of NRP2 on the proliferation, migration, invasion, and cancer stem cell (CSC) properties of HNC cells was examined by MTS, soft agar, clonogenic, transwell migration and invasion assays, and sphere formation assays. Signaling explorer antibody array, western blot, and qPCR were performed toward the investigation of a molecular mechanism that is related to NRP2.

RESULTS

NRP2 was highly expressed in HNC and positively correlated with LN metastasis and advanced tumor stage and size in patients. Using loss- or gain-of-function approaches, we found that NRP2 promoted the proliferative, migratory, and invasive capacities of human HNC cells. Furthermore, NRP2 regulated Sox2 expression to exhibit aggressiveness and CSC properties of human HNC cells. We demonstrated that p90 ribosomal S6 kinase 1 (RSK1) elevates the aggressiveness and CSC properties of human HNC cells, possibly by mediating NRP2 and Sox2. Zeb1 was necessary for executing the NRP2/RSK1/Sox2 signaling pathway during the induction of epithelial-to-mesenchymal transition (EMT) and aggressive behaviors of human HNC cells. Moreover, the methanol extract of Codium fragile (MECF) repressed NRP2 expression, inhibiting the RSK1/Sox2/Zeb1 axis, which contributed to the reduction of aggressive behaviors of human HNC cells.

CONCLUSIONS

These findings suggest that NRP2 is a critical determinant in provoking EMT and aggressive behaviors in human HNC through the RSK1/Sox2/Zeb1 axis, and MECF may have the potential to be a novel NRP2 inhibitor for treating metastasis in HNC patients.

Tumor immune microenvironment in odontogenic carcinomas: Evaluation of the therapeutic potential of immune checkpoint blockade

BACKGROUND

Despite recent advances in the use of immune checkpoint blockade (ICB) across various cancer types, its efficacy in odontogenic carcinomas remains unexplored. This study aims to investigate PD-L1 expression and the tumor immune microenvironment (TIME) in odontogenic carcinomas to determine the therapeutic potential of ICB and the significance of immune markers.

METHODS

The expressions of PD-L1 and T cell markers (CD3, CD8, and FOXP3) were visualized by immunohistochemistry in 21 tissue samples of odontogenic carcinomas. Tumoral PD-L1 expression and the density and spatial distribution of T cell subsets were evaluated, from which TIME was determined. The associations of the variables with clinicopathological and prognostic factors were statistically analyzed.

RESULTS

PD-L1 was positively expressed in 52.4% (11/21) of the cases studied. Among tumor types, ameloblastic carcinoma showed significantly higher PD-L1 expression (p = 0.016). TIME based on the intratumoral and stromal T cell distribution was immune-inflamed in 61.9% (13/21) and immune-excluded in 38.1% (8/21), with no immune-desert cases. PD-L1 expression was associated with the densities of all intratumoral T cell subsets (p = 0.03 for CD3, p = 0.03 for CD8, and p = 0.008 for FOXP3) but not with those of stromal T cells. High PD-L1 expression was associated with larger tumor size (p = 0.021), while the intratumoral CD8/CD3 ratio was inversely correlated with tumor size (p = 0.048).

CONCLUSION

These findings indicate the involvement of adaptive immune resistance in a subset of odontogenic carcinomas and support the therapeutic potential of ICB in patients with these rare malignancies.

Sialadenoma papilliferum-like intraductal papillary tumour: an emerging entity with intercalated duct differentiation showing MAPK pathway activation in both ductal and myoepithelial cells

Sialadenoma papilliferum-like intraductal papillary tumour (SP-IPT) is a recently described salivary gland tumour that shows identical morphology to sialadenoma papilliferum (SP) except for the lack of an exophytic papillary component. However, the immunohistochemical phenotypes and molecular profiles of SP-IPT remain unclear. This study aims to report new cases of SP-IPT and to determine its cellular differentiation and molecular basis. After histopathological review, four cases of SP-IPT were retrieved. Immunohistochemical staining was performed to analyse the expression patterns of cytokeratin 7 (CK7), p63, smooth muscle actin (SMA), vimentin, S100, mammaglobin, androgen receptor, SOX10, BRAF V600E-mutated protein, and phosphorylated ERK. Sanger sequencing was performed to determine the mutation status of the BRAF, KRAS, NRAS, and HRAS genes. All four cases affected the posterior mandible with a mean age of 62 years and a male-to-female ratio of 3:1. Histologically, all cases consisted of multiple tubular and cystic structures with varying sizes and shapes. The tubulocystic components were lined by a double or few-layered epithelium frequently showing a micropapillary pattern. The outer layer consisted of a rim of myoepithelial cells, which were CK7+/p63+/SMA+/vimentin+/S100+/SOX10+. The inner ductal cells were CK7+/S100+/SOX10+, consistent with intercalated duct differentiation. All cases harboured BRAF V600E mutations, but no other mutations were detected. The BRAF V600E-mutated protein and phosphorylated ERK were expressed in both ductal and myoepithelial cells. These findings demonstrate the immunohistochemical and molecular similarities between SP-IPT and SP and the role and extent of MAPK pathway activation in the pathogenesis of SP-IPT.

[Application value of questionnaires in the screening obstructive sleep apnea syndrome in pregnancy across trimesters]

Objective: To evaluate the clinical utility value of questionnaires of Berlin, STOP, STOP-Bang (SBQ), Epworth Sleepiness Scale (ESS) in screening obstructive sleep apnea syndrome (OSAS) in pregnant women of different trimesters. Methods: Consecutive pregnant women at high risk for OSAS were enrolled from January, 2021 to April, 2022 at the obstetric clinic of Peking University People's Hospital. They completed questionnaires of Berlin, STOP, SBQ, ESS and also underwent an overnight polysomnography (PSG). To evaluate the accuracy of questionnaires of Berlin, STOP, SBQ, ESS, sensitivity, specificity, positive predictive values, negative predictive values and the area under the receiver operating characteristics (ROC) curve of these questionnaires in pregnancy across trimesters (Pregnancy 1-15 weeks was the first stage, pregnancy 16-27 weeks was the second stage, and pregnancy 28-40 weeks was the third stage) were calculated. Results: A total of 100 pregnant women [(34.5±4.3) years old (26-46 years old)] were included in this study, including 20, 35 and 45 pregnant women in the first, second and third trimester of pregnancy, respectively. Based on PSG results, 45 (45%) of 100 pregnant women were diagnosed with OSAS. The overall predictive values of the four questionnaires were not good, area under[AUC(95%CI)] the ROC curve ESS, Berlin questionnaire STOP and SBQ were 0.54(0.43, 0.66), 0.59 (0.47, 0.70), 0.62(0.51, 0.73) and 0.61 (0.49, 0.72), respectively, sensitivity was 35.6%, 65.9%, 48.9%, 28.9%, specificity was 71.7%, 52.5%, 73.6%, 92.5%. When categorized according to trimesters, the predicted values of the four questionnaires increased in the first trimester, the AUC (95%CI) of STOP questionnaire was 0.81 (0.61, 1.00), sensitivity was 75.0%, specificity was 87.5%. Conclusion: The overall predictive power of the four screening questionnaires is limited in pregnant women. But predictive value of STOP questionnaire is acceptable in the first trimester.

Apoptotic activity of genipin in human oral squamous cell carcinoma in vitro by regulating STAT3 signaling

Genipin, a natural compound derived from the fruit of Gardenia jasminoides Ellis, was reported to have activity against various cancer types. In this study, we determined the underlying mechanism for genipin-induced cell death in human oral squamous cell carcinoma (OSCC). The growth-inhibitory effects of genipin in human OSCC cells was examined by the Cell Counting Kit-8 and soft agar assays. The effects of genipin on apoptosis were assessed by nuclear morphological changes by 4',6-diamidino-2-phenylindole staining, measurement of the sub-G1 population, and Annexin V-fluorescein isothiocyanate/propidium iodide double staining. The underlying mechanism of genipin activity was analyzed by western blot analysis, subcellular fractionation of the nucleus and cytoplasm, immunocytochemistry, and quantitative real-time polymerase chain reaction. Genipin inhibited the growth of OSCC cells and induced apoptosis, which was mediated by a caspase-dependent pathway. Genipin reduced the phosphorylation of signal transducer and activator of transcription 3 (STAT3) at Tyr705 and its nuclear localization. Furthermore, inhibition of p-STAT3Tyr705 levels following genipin treatment was required for the reduction of survivin and myeloid cell leukemia-1 (Mcl-1) expression, leading to apoptotic cell death. The genipin-mediated reduction in survivin and Mcl-1 expression was caused by transcriptional and/or posttranslational regulatory mechanisms. The results provide insight into the regulatory mechanism by which genipin induces apoptotic cell death through the abrogation of nuclear STAT3 phosphorylation and suggest that genipin may represent a potential therapeutic option for the treatment of human OSCC.

Infarction of basal cell adenoma of the parotid gland: First case report and literature review on CTNNB1 I35T mutations in salivary basal cell neoplasms

Infarction has rarely been reported in some types of salivary gland tumors. In this study, we present the first case of infarction occurring in salivary basal cell adenoma. A 62-year-old male presented with swelling in the left parotid region. Histopathological examination revealed extensive central necrosis surrounded by a rim of viable tumor tissue showing the typical histology of basal cell adenoma. Nuclear β-catenin expression and the CTNNB1 p.I35T (c.104 T > C) mutation were identified in the tumor. A diagnosis of basal cell adenoma with central necrosis was made, and the postoperative period was uneventful. In addition, we review the literature on CTNNB1 I35T mutations in basal cell neoplasms of the salivary glands. Awareness of the possible occurrence of infarction and the high frequency of the unique mutation in basal cell adenoma may help in the differential diagnosis of salivary gland tumors.

[Relationships between hypertensive disorders in pregnancy and obstructive sleep apnea syndrome]

Objective: To investigate the impact of obstructive sleep apnea syndrome (OSAS) on pregnancy outcomes, especially the relationship between OSAS and hypertensive disorders in pregnancy (HDP). Methods: A total of 228 pregnant women with high risk of OSAS who underwent sleep monitoring during pregnancy in Peking University People's Hospital from January 2021 to April 2022 were collected by reviewing their medical records for retrospective analysis. According to the diagnosis of OSAS, the pregnant women were divided into OSAS group (105 cases) and non-OSAS group (123 cases). The non-parametric Mann-Whitney U test, χ2 test or Fisher's exact test were used to compare the general data and maternal and fetal outcomes between the two groups, and the occurrence of each type of HDP was further compared. Results: (1) Compared with the non-OSAS group, the median pre-pregnancy body mass index (23.6 vs 27.6 kg/m2) and the proportion of snoring [28.9% (33/114) vs 59.2% (61/103)] in the OSAS group were higher, and the differences were both statistically significant (both P<0.001). (2) The incidence of HDP [67.6% (71/105) vs 39.0% (48/123)] and gestational diabetes mellitus [GDM; 40.0% (42/105) vs 26.8% (33/123)] of pregnant women in the OSAS group were higher than those in the non-OSAS group, and the median delivery week was shorter than that in the non-OSAS group (38.4 vs 39.0 weeks). The differences were all statistically significant (all P<0.05). Between-group differences for the delivery way, postpartum hemorrhage, the rate of intensive care unit admission, preterm birth, small for gestational age infants, neonatal asphyxia, the rate of neonatal intensive care unit admission, newborn birth weight and the proportion of umbilical artery blood pH<7.00 were not statistically significant (all P>0.05). (3) Compared with the non-OSAS group, the incidence of chronic hypertension [11.4% (14/123) vs 22.9% (24/105)] and chronic hypertension with superimposed pre-eclampsia [11.4% (14/123) vs 30.5% (32/105)] were higher in the OSAS group, and the differences were both statistically significant (both P<0.01). Conclusion: OSAS is related to HDP (especially chronic hypertension and chronic hypertension with superimposed pre-eclampsia) and GDM, which could provide a practical basis for the screening, diagnosis and treatment of OSAS in pregnant women at high risk.

Adenoid Ameloblastoma Shares Clinical, Histologic, and Molecular Features With Dentinogenic Ghost Cell Tumor: The Histologic Spectrum of WNT Pathway-Altered Benign Odontogenic Tumors

An epithelial odontogenic tumor called adenoid ameloblastoma (AA) has recently been included in the new WHO classification. However, AA has considerable overlapping features with a preexisting entity, dentinogenic ghost cell tumor (DGCT). This study compared the clinical, histologic, and molecular characteristics of AA and DGCT. Eight cases of odontogenic tumors initially diagnosed as AA or DGCT were included in this study. Quantitative histologic analysis, β-catenin immunohistochemistry, and molecular profiling using next generation sequencing were performed. Additionally, accumulated clinical data of AA and DGCT were statistically analyzed. Nuclear β-catenin accumulation was detected in all cases in common, although the tumors studied histologically consisted of varying combinations of the AA-like phenotype, ghost cells, and dentinoid. However, CTNNB1 hotspot mutations were not found in any case. Instead, loss-of-function mutations in tumor suppressor genes involved in the WNT pathway, including the APC, SMURF1, and NEDD4L genes, were found regardless of histologic type. In addition, KRT13 mutations were detected in 2 cases with a high proportion of ghost cells. Finally, a literature analysis revealed clinical similarities between the previously reported cases of AA and DGCT. These findings suggest that from a clinical and molecular point of view, AA and DGCT represent a histologic spectrum of WNT pathway-altered benign odontogenic tumors rather than 2 distinct tumors. Moreover, previously unidentified keratin mutations may be associated with ghost cell formation found in specific types of odontogenic lesions.

Malignant peripheral nerve sheath tumor of the maxilla: Case report and review of the literature with emphasis on its poor prognosis

Malignant peripheral nerve sheath tumor (MPNST) is a spindle cell sarcoma with poor prognosis. Although patients with neurofibromatosis type 1 (NF1) have a higher risk of MPNST, it can also occur in the sporadic setting and may rarely arise centrally within bone. In this study, we present an extremely rare case of intraosseous MPNST of the maxilla arising in a 38-year-old female with no history of NF1. Despite radical surgery and postoperative radiotherapy, the patient died due to multiple distant metastases 1 year after treatment. According to the results of the literature analysis performed in this study, maxillary MPNST cases have worse clinical outcomes than general MPNSTs. In addition, it seems that NF1 and histological necrosis are poor prognostic indicators in patients with maxillary MPNST.

Targeting tumor-intrinsic PD-L1 suppresses the progression and aggressiveness of head and neck cancer by inhibiting GSK3β-dependent Snail degradation

PURPOSE

PD-L1 is an immune checkpoint protein that allows cells to evade T-cell-mediated immune responses. Herein, we uncover a tumor-intrinsic mechanism of PD-L1 that is responsible for the progression and aggressiveness of HNC and reveal that the extracts of a brown alga can target the tumor-intrinsic signaling pathway of PD-L1.

METHODS

The biological functions of PD-L1 in the proliferation and aggressiveness of HNC cells in vitro were examined by metabolic activity, clonogenic, tumorigenicity, wound healing, migration, and invasion assays. The clinical importance of PD-L1 in the prognosis of patients with HNC was analyzed by immunohistochemistry. The relationship between PD-L1 and EMT was confirmed via western blotting, qPCR, and immunocytochemistry.

RESULTS

Through our in silico approach, we found that PD-L1 was upregulated in HNC and was correlated with an unfavorable clinical outcome in patients with HNC. PD-L1 was crucial for promoting tumor growth, both in vitro and in vivo. High expression of PD-L1 was closely correlated with LN metastasis in OSCC. PD-L1 facilitated the cytoskeletal reorganization and aggressiveness of HNC cells. Moreover, PD-L1 enhanced the EMT of HNC cells by regulating the Snail/vimentin axis. Consistently, MEIO suppressed the PD-L1/Snail/vimentin axis, thereby inhibiting the aggressiveness of HNC cells. Inhibition of PD-L1 induced by PD-L1 silencing or MEIO treatment caused Snail degradation through a GSK3β-dependent mechanism. The tumor-intrinsic function of PD-L1 could be attributed to the regulation of the GSK3β/Snail/vimentin axis.

CONCLUSION

The discovery of MEIO targeting the tumor-intrinsic function of PD-L1 may prove particularly valuable for the development of novel and effective anticancer drug candidates for HNCs overexpressing PD-L1.

Myxoid liposarcoma metastatic to the mandible: First case report and review of the literature

Unlike other soft tissue sarcomas, myxoid liposarcoma tends to metastasize to bone even before developing lung metastases. In this report, we present a unique case of myxoid liposarcoma metastatic to the mandible. A 40-year-old male who had a history of myxoid liposarcoma in the buttock presented with paresthesia in the left lower face and mandible. Radiographic examination revealed an ill-defined radiolucent lesion with cortical destruction in the left mandibular body and ramus. Histopathological examination showed a mixture of small lipoblasts and round primitive mesenchymal cells in a myxoid stroma. Hypercellular areas comprising high-grade round cells were frequently found. The final diagnosis of metastatic myxoid liposarcoma was made. Despite postoperative chemoradiotherapy, further metastases occurred in the lungs and liver, and the patient died of the tumor 23 months after the treatment of the mandibular lesion. This is the first report of myxoid liposarcoma metastatic to the jaw, which may help in the differential diagnosis of intraosseous myxoid tumors of the jaws and highlights unfavorable clinical outcome of metastatic high-grade myxoid liposarcoma.

BRAF V600E and previously unidentified KRAS G12C mutations in odontogenic tumors may affect MAPK activation differently depending on tumor type

Although several types of odontogenic tumors share the same mutations in MAPK pathway genes, their effects on MAPK activation remain unclarified. This study aimed to evaluate the associations between these mutations and ERK phosphorylation in ameloblastoma and mixed odontogenic tumors (MOTs) and to analyze the expression pattern of phosphorylated ERK (p-ERK) for determining the involvement of MAPK activation in the development and progression of odontogenic tumors. Forty-three odontogenic tumors consisting of 18 ameloblastomas and 25 MOTs were analyzed for BRAF, KRAS, and NRAS mutations by Sanger sequencing. The expressions of BRAF^V600E protein and p-ERK were detected by immunohistochemistry. The associations of mutation status and p-ERK expression were statistically analyzed. In ameloblastoma cells, the effect of BRAF^V600E inhibition on MAPK activation was investigated. In benign MOTs, BRAF^V600E mutations were neither expressed at the protein level nor associated with p-ERK expression. In contrast, BRAF^V600E -mutant ameloblastic fibrosarcoma showed co-expression of BRAF V600E protein and p-ERK, especially in the sarcomatous component. In ameloblastoma, p-ERK was predominantly expressed in the tumor periphery showing a significant correlation with BRAF^V600E mutations, and in vitro BRAF^V600E inhibition decreased ERK phosphorylation. KRAS^G12C mutations, previously unidentified in odontogenic tumors, were detected in one case each of benign MOT and ameloblastoma; only the latter was high-p-ERK. In conclusion, unlike in benign MOTs, BRAF^V600E and KRAS^G12C mutations lead to MAPK activation in ameloblastoma, suggesting their role as therapeutic targets. p-ERK intratumoral heterogeneity indicates that MAPK pathway activation may be associated with sarcomatous proliferation of ameloblastic fibrosarcoma and infiltrative behavior of ameloblastoma. This article is protected by copyright. All rights reserved.

Methanol extract of Sedum oryzifolium and its constituent, trehalose, impede the invasiveness of oral squamous cell carcinoma cell lines via downregulation of Slug

BACKGROUND

Sedum species are reported to possess diverse pharmacological activities in various solid tumors. However, the anticancer functions of Sedum orizyfolium and its constituents have never been determined in human cancers.

PURPOSE

The present study focused on addressing the inhibition efficacy of the methanol extract of S. orizyfolium (MESO) and its constituents and the molecular mechanism underlying invasion and epithelial-to-mesenchymal transition (EMT) in oral squamous cell carcinoma (OSCC) cell lines.

STUDY DESIGN/METHODS

After MESO treatment, a wound-healing assay, an invasion assay, and immunocytochemistry were performed in OSCC cell lines, coupled with in silico analysis and immunohistochemistry in OSCC patient samples, to investigate the role of the EMT transcription factor Slug. Trehalose, an active component of MESO, was identified through gas chromatography-mass spectrometry.

RESULTS

Among the methanol extracts of 18 various wild plants from South Korea, MESO exhibited the highest anticancer functionality in OSCC cells by downregulating Slug expression. In silico analysis and immunohistochemistry indicated that elevated Slug levels are remarkably associated with tumor progression and invasion in patients with OSCC, suggesting that changes in Slug expression alter EMT progression and invasion in OSCC. Notably, treatment with trehalose, a sugar component of MESO, inhibited invasiveness and Slug expression in OSCC cells.

CONCLUSION

Cumulatively, this study highlighted the beneficial role of MESO and trehalose in the inhibition of invasiveness of OSCC cells via suppression of Slug expression and suggested a new design for potential chemotherapeutic drugs against OSCC.

Molecular mechanism underlying the apoptotic modulation by ethanol extract of Pseudolarix kaempferi in mucoepidermoid carcinoma of the salivary glands

Background

Pseudolarix kaempferi is a traditional Chinese natural product that possesses the potential cytotoxic effects against cancer. However, the precise molecular mechanism underlying its cytotoxic effects has not yet been completely elucidated. Here, we clarify the mechanism via which the ethanol extract of P. kaempferi (EEPK) leads to cytotoxicity mediated by apoptosis in mucoepidermoid carcinoma (MEC) originating from the salivary glands.

Methods

We investigated the mechanism underlying the anticancer efficacy of EEPK in human MEC in vitro by assessing mitochondrial dysfunction, mRNA levels, and morphological changes in apoptotic cell nuclei as well as by using a cytotoxicity assay, flow cytometric analysis, and western blotting.

Results

EEPK inhibited the growth of two human MEC cells and stimulated the induction of caspase-mediated apoptosis that was accompanied by mitochondrial membrane depolarization. Compared with the vehicle control groups, EEPK decreased myeloid cell leukemia-1 (Mcl-1) expression in both cells whereas it significantly decreased B cell lymphoma-2 (Bcl-2) expression in MC3 cells only. The EEPK-induced altered Mcl-1 expression was caused by translational inhibition and proteasomal degradation. Additionally, EEPK significantly increased p-Bcl-2 (Ser⁷⁰) expression regardless of its total forms by facilitating the activation of the c-Jun N-terminal kinase (JNK) signaling pathway, which exhibited cell context dependency. Nevertheless, JNK activation following EEPK treatment was, at least in part, required for the proapoptotic efficacy of EEPK in both cells.

Conclusions

This study revealed that EEPK-induced alterations of Mcl-1 inhibition and JNK/Bcl-2 phosphorylation cause apoptosis and provided basic preclinical data for future clinical trials regarding therapy for patients with MEC.

Graphic abstract

Orthokeratinized odontogenic cyst: A large series and comprehensive literature review with emphasis on synchronous multiple occurrence and neoplastic transformation

OBJECTIVES

The objective of this study was to demonstrate the clinical, radiologic, and histologic features of orthokeratinized odontogenic cyst (OOC); determine the characteristics of multiple OOCs; and present rare but significant manifestations of OOC.

STUDY DESIGN

A clinical, radiologic, and histopathologic study of 65 primary and 2 recurrent OOC cases was performed retrospectively along with a comprehensive literature review.

RESULTS

OOCs shared similar radiologic findings with odontogenic keratocyst, yet some showed features that have not been previously described: root resorption and radiopaque foci. Histologic review revealed a unique histiocytic lining and some findings suggestive of the multipotentiality of the odontogenic epithelium. The analysis of patients with multiple OOCs demonstrated that multiple OOCs occurred synchronously with a marked predilection for young male adults. Two unusual cases were also identified: an OOC combined with a BRAF^V600E ameloblastoma and a recurrent OOC with malignant transformation.

CONCLUSIONS

This largest series presents previously unreported radiographic and histopathologic features that can be seen in OOC. Multiple OOCs have clinical characteristics distinct from those of solitary cases. The first reported OOC associated with ameloblastoma suggests the involvement of oncogenic mutations in odontogenic tumorigenesis. Although OOC shows a low recurrence rate, the possibility of malignant transformation of recurrent OOCs should be emphasized.

SOX7 blocks vasculogenic mimicry in oral squamous cell carcinoma

BACKGROUND

Vasculogenic mimicry (VM) is the formation of an alternative circulatory system by aggressive tumor cells. The characteristics of VM and its underlying mechanism in oral squamous cell carcinoma (OSCC) remain unclear. This study aims to determine the relationship between VM in OSCC tissues and clinical outcomes and to investigate the biological role of SOX7 in VM in OSCC cells.

METHODS

CD31/PAS staining was performed to evaluate VM in OSCC tissue. The relationships between VM and clinicopathological variables, and VM and SOX7 levels were analyzed. The correlation between SOX7 levels and cancer cohorts was investigated using in silico analysis. VM formation assay was performed to observe VM in vitro. To investigate the role of SOX7 in VM formation, SOX7 was transiently over-expressed in SCC-9 cells. VM-modulating genes were identified by Western blotting.

RESULTS

We found a positive correlation between VM and lymph node metastasis and patient survival in OSCC (p = 0.003). In silico analysis from The Cancer Genome Atlas and Gene Expression Omnibus database showed that down-regulation of SOX7 expression was significantly correlated with OSCC patients (p = 0.0187) and lymph node metastasis (p = 0.0017). We also found that the presence of VM in OSCC tissue was inversely associated with SOX7 expression (p = 0.020). We observed that overexpression of SOX7 impaired VM formation by reducing the expression of VE-cadherin, thereby inhibiting cell migration and invasion.

CONCLUSION

These results suggest that SOX7 plays an important role in the regulation of VM formation and may inhibit OSCC metastasis.

Risk factors for postoperative CSF leakage after endonasal endoscopic skull base surgery: a meta-analysis and systematic review

BACKGROUND

Cerebrospinal fluid (CSF) leakage is a complication that any surgeon working in the field of skull base surgery does not wish to encounter. The surgical approach to the skull base often varies, and the various sizes and locations of skull base lesions make it difficult to determine the cause of CSF leakage. However, it is useful to investigate which factors contribute to postopera- tive CSF leakage.

METHODS

Related studies were identified by searching the following databases: PubMed/Medline, Embase, and Web of Sciences through December 2019. Random-effects models were used to calculate odds ratios (ORs) and 95% confidence intervals (CIs). The Newcastle-Ottawa scale was used to evaluate the quality of observational studies.

RESULTS

Our search yielded 56 retrospective cohort studies involving a total of 11,826 skull base surgical procedures. The overall rate of postoperative CSF leakage was 7.2%. The effect of obesity on postoperative CSF leakage had an OR of 1.88, and the effect of perioperative radiotherapy on postoperative CSF leakage yielded an OR of 1.87. High intraoperative CSF flow rate also had a significant OR of 2.98. On the other hand, a pedicled vascularized flap efficiently reduced the risk of postoperative CSF leakage. Defect size and the presence or absence of a lumbar drain had no effect on postoperative CSF leakage.

CONCLUSIONS

This comprehensive quantitative assessment of postoperative CSF leakage showed that obesity, perioperative radiotherapy, and high intraoperative CSF flow rate raised the risk of CSF leakage; however, a pedicled vascularized flap can ef- fectively reduce the risk of postoperative CSF leakage.

Extended approach or usage of nasoseptal flap is a risk factor for olfactory dysfunction after endoscopic anterior skullbase surgery: results from 928 patients in a single tertiary center

BACKGROUND

The aim of this study was to compare olfactory function change in patients who underwent endoscopic skull-base surgery.

METHODOLOGY

A total of 928 patients were included in this retrospective study. Olfactory function was measured using the non- validated Likert scale (0â€"100), the Cross-Cultural Smell Identification Test (CC-SIT) and the butanol threshold test (BTT). Patients were divided into two groups: an endoscopic trans-sellar approach group (ETA, n = 768) and an extended endoscopic endonasal approach group (EEEA, n = 160). The ETA group was sub-divided into Nasoseptal flap (NSF) and no NSF groups.

RESULTS

Non-validated olfactory function significantly worsened in the EEEA and ETA-NSF groups compared with that in the ETA- no NSF group for at least 6 months post-operatively. Validated olfactory impairment (BTT and CC-SIT) was also significantly worse in the EEEA and NSF groups compared with that in the ETA-no NSF group 3 months post-operatively. Additionally, the degrees of non-validated and validated olfactory deterioration were not significantly different between the EEEA and ETA-NSF groups. We also found that CC-SIT score changes were significantly impaired in tuberculum sellae meningioma patients than in craniopharyn- gioma patients.

CONCLUSIONS

We conclude that NSF was the key factor that led to olfactory impairment after endoscopic skull-base surgery.

Discrepancy between immunohistochemistry and sequencing for BRAF V600E in odontogenic tumours: Comparative analysis of two VE1 antibodies

BACKGROUND

Although immunohistochemistry (IHC) along with molecular tests has been investigated in ameloblastoma for BRAF V600E detection, VE1 IHC has not been studied in odontogenic carcinomas (OCs) and benign mixed epithelial and mesenchymal odontogenic tumours (BMOTs). Here, we performed BRAF V600E mutation analysis, examined the expression pattern of VE1 IHC, and comparatively evaluated the performance of two VE1 antibodies in ameloblastomas, OCs and BMOTs.

METHODS

BRAF V600E detection was performed using Sanger sequencing in a total of 47 odontogenic tumours: 28 ameloblastomas, 6 OCs and 13 BMOTs. VE1 IHC was conducted using two different antibodies (IHC-A and IHC-V), and their performance was analysed by calculating the sensitivity and specificity compared with sequencing.

RESULTS

BRAF V600E mutations were identified in 24/28 (85.7%) ameloblastomas, 2/5 (40.0%) ameloblastic carcinomas (ACs), 3/7 (42.9%) ameloblastic fibromas and 1/2 (50.0%) ameloblastic fibro-odontomas. In the presence of the mutation, VE1 showed diffuse cytoplasmic staining in ameloblastomas and ACs, whereas all BMOTs were negative for VE1. IHC-A and IHC-V yielded a sensitivity of 76.7% and 60.0%, respectively, although both antibodies showed 100% specificity.

CONCLUSION

OCs and BMOTs have BRAF V600E mutations in common at lower frequencies than ameloblastoma. Diffuse VE1 cytoplasmic staining in AC suggests the utility of MAPK-targeted therapy as selectively applied in ameloblastoma, and consistent VE1 false-negative expression in BMOTs requires further investigation. Considering the high specificity but low sensitivity of VE1 IHC, molecular tests should be performed to determine the presence of BRAF V600E mutations in odontogenic tumours.

Abstract 362: The regulation of SOX7 and its tumor suppressive role in oral squamous cell carcinoma

SRY-related HMG-box 7(SOX7), a transcription factor belonging to the SOX family, has been reported to be down-regulated in some types of cancers. However, its biologic role in oral squamous cell carcinoma (OSCC) remains unknown. We found expression of SOX7 protein was decreased in OSCC tissues compared with normal oral mucosa. SOX7 expression in patients with OSCC was inversely associated with positive lymph node metastasis, advanced TNM stage, and poor prognosis. These results were in accordance with data obtained from our in vitro experiments on the OSCC cell lines. Moreover, ectopic expression of SOX7 suppressed cell proliferation, migration, and invasion in HSC-4 and SCC-9 cells. Importantly, we discovered that SOX7 expression likely inhibited vasculogenic mimicry formation associated with clinically poor outcome and impaired expression of VE-cadherin in OSCC cell lines as well as lung cancer and breast cancer cells. Our findings suggest that SOX7 could be a potential marker for predicting the prognosis of patients with OSCC and plays an important role as a tumor suppressor in oral tumorigenesis and progression. This work was supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Science, ICT, and Future Planning [2017R1D1A1B03029317, 2018R1D1A1B07043080, and 2019R1A2C1085896].

Citation Format: Chi-Hyun Ahn, Kyoung Ok Hong, Ji-Ae Shin, Seong-Doo Hong, Sung-Dae Cho. The regulation of SOX7 and its tumor suppressive role in oral squamous cell carcinoma [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 362.

Oridonin induces the apoptosis of mucoepidermoid carcinoma cell lines in a myeloid cell leukemia‑1‑dependent manner

Oridonin, an active diterpenoid isolated from Rabdosia rubescens, has been reported to exhibit anticancer activities in several tumors. The aim of the present study was to investigate the anticancer effects and molecular mechanisms of oridonin in mucoepidermoid carcinoma (MEC). Treatment with oridonin induced the apoptosis of MC‑3 and YD‑15 cell and inhibited the expression of myeloid cell leukemia‑1 (MCL‑1) through the regulation of the protein level through post‑translational regulation in these cell lines. Oridonin significantly increased the expression level of truncated Bid (t‑Bid) as a downstream target of MCL‑1 and subsequently decreased the mitochondrial membrane potential. The ectopic expression of MCL‑1 protein was sufficient to reverse the induction of apoptosis and the increased t‑Bid expression induced by oridonin in both cell lines. Taken together, these results suggest that oridonin exerts an apoptotic effect through the modulation of MCL‑1 and t‑Bid in human MEC cell lines and may thus be a potential anticancer drug candidate for the treatment of human MEC.

Tumor budding is associated with poor prognosis of oral squamous cell carcinoma and histologically represents an epithelial-mesenchymal transition process

In this study, we aimed to identify whether tumor budding is associated with the progression and prognosis of oral squamous cell carcinoma (OSCC) and investigate the correlation between tumor budding and regulators of epithelial-mesenchymal transition (EMT). Fifty-six cases of OSCC were selected and their tumor budding status was reviewed using archived hematoxylin and eosin-stained slides. In addition, the expression of EMT regulators was evaluated by immunohistochemistry using antibodies against Snail and Twist. Tumor budding was observed in 19 (33.9%) of the 56 cases of OSCC. Tumor budding was strongly associated with lymph node metastasis (P = .001) and shorter overall survival (P = .002). The expression of Snail and Twist was correlated with lymph node metastasis (P < .001 and .002, respectively) and poorer overall survival (P = .024 and .024, respectively). Tumor budding was significantly associated with the expression of Snail (P = .003) and showed a tendency toward higher expression of Twist (P = .08). Therefore, our results suggest that tumor budding is significantly associated with poor prognosis in patients with OSCC and histologically represents an EMT process in OSCC.

In vitro and in vivo anti-cancer activity of silymarin on oral cancer

Silymarin, a standardized extract from milk thistle fruits has been found to exhibit anti-cancer effects against various cancers. Here, we explored the anti-cancer activity of silymarin and its molecular target in human oral cancer in vitro and in vivo. Silymarin dose-dependently inhibited the proliferation of HSC-4 oral cancer cells and promoted caspase-dependent apoptosis. A human apoptosis protein array kit showed that death receptor 5 may be involved in silymarin-induced apoptosis, which was also shown through western blotting, immunocytochemistry, and reverse transcription-polymerase chain reaction. Silymarin increased cleaved caspase-8 and truncated Bid, leading to accumulation of cytochrome c. In addition, silymarin activated death receptor 5/caspase-8 to induce apoptotic cell death in two other oral cancer cell lines (YD15 and Ca9.22). Silymarin also suppressed tumor growth and volume without any hepatic or renal toxicity in vivo. Taken together, these results provide in vitro and in vivo evidence supporting the anti-cancer effect of silymarin and death receptor 5, and caspase-8 may be essential players in silymarin-mediated apoptosis in oral cancer.

Primary sinonasal mucosal melanoma simulated as cystic lesions: a case report

Sinonasal mucosal melanoma (SNMM) in the maxillary sinus is a rare disease condition. Compared to oral mucosal melanoma, SNMM has a bulky, exophytic, and polypoid appearance, is weakly pigmented, and associated with unspecific symptoms. Due to these features, SNMM in the maxillary sinus has been misdiagnosed as nasal polyps and chronic sinusitis. In this case report, we described SNMM occurring in the right maxillary sinus simulated as a cystic or benign lesion. Cortical bone thinning and expansion were observed around the mass. The excised soft mass was encapsulated and weakly pigmented. The mass was clearly excised and covered with a pedicled buccal fat pad graft. Diagnosis using immunohistochemistry with S-100 and homatropine methylbromide-45 (HMB-45) is critical for proper treatment.

Clinical implications of serum galactomannan measurement in patients with acute invasive fungal rhinosinusitis

BACKGROUND

Acute invasive fungal rhinosinusitis (AIFR) is an aggressive opportunistic infection with a high mortality rate. Recently, non-invasive techniques have been introduced for diagnosis of invasive fungal disease. The purpose of this study is to evaluate the diagnostic significance of serum galactomannan measurement in patients with AIFR.

METHODOLOGY

We conducted a retrospective case-control study of 28 patients with AIFR and 36 fungus ball (FB) patients. We evaluated clinical, laboratory, and pathologic findings along with disease course.

RESULTS

In 28 patients with AIFR, there were 21 cases of invasive aspergillosis (IA) and 7 cases of invasive mucormycosis (IM). The control group was comprised of 36 patients with FB. The three-group analysis showed a statistically significant difference among the groups. At the cut-off value of 0.48, the sensitivity and specificity were 71.4% and 93.0%, respectively. Comparison of mean serum galactomannan levels in 5 non-survivors and 9 survivors at initial measurement showed no significant difference, but that became significantly different 1 week later. Statistical analysis showed that the levels of serum galactomannan decreased significantly according to the measurement-point in within survivor-group analysis. The difference in between survivor-groups analysis was also significant.

CONCLUSION

Serum galactomannan measurement seems useful for early diagnosis and discrimination of fungal species in patients with AIFR. In addition, clinical outcomes may be related to the levels and patterns of serum galactomannan, especially in IA. The appropriate measurement of galactomannan might be helpful in treating the patients at high risk for AIFR.

Clinical implications of serum galactomannan measurement in patients with acute invasive fungal rhinosinusitis

BACKGROUND

Acute invasive fungal rhinosinusitis (AIFR) is an aggressive opportunistic infection with a high mortality rate. Recently, non-invasive techniques have been introduced for diagnosis of invasive fungal disease. The purpose of this study is to evaluate the diagnostic significance of serum galactomannan measurement in patients with AIFR.

METHODOLOGY

We conducted a retrospective case-control study of 28 patients with AIFR and 36 fungus ball (FB) patients. We evaluated clinical, laboratory, and pathologic findings along with disease course.

RESULTS

In 28 patients with AIFR, there were 21 cases of invasive aspergillosis (IA) and 7 cases of invasive mucormycosis (IM). The control group was comprised of 36 patients with FB. The three-group analysis showed a statistically significant difference among the groups. At the cut-off value of 0.48, the sensitivity and specificity were 71.4% and 93.0%, respectively. Comparison of mean serum galactomannan levels in 5 non-survivors and 9 survivors at initial measurement showed no significant difference, but that became significantly different 1 week later. Statistical analysis showed that the levels of serum galactomannan decreased significantly according to the measurement-point in within survivor-group analysis. The difference in between survivor-groups analysis was also significant.

CONCLUSION

Serum galactomannan measurement seems useful for early diagnosis and discrimination of fungal species in patients with AIFR. In addition, clinical outcomes may be related to the levels and patterns of serum galactomannan, especially in IA. The appropriate measurement of galactomannan might be helpful in treating the patients at high risk for AIFR.

Twist and Snail expression in tumor and stromal cells of epithelial odontogenic tumors

BACKGROUND

The aims of this study were to evaluate expression of Twist and Snail in tumor and stromal cells of epithelial odontogenic tumors and to analyze relationships between Twist and Snail expression and between tumor and stromal expression.

METHODS

Immunohistochemistry was performed using Twist and Snail antibodies in 60 ameloblastomas (AMs; 20 solid/multicystic, 20 unicystic, and 20 recurrent), six ameloblastic carcinomas (ACs), 10 adenomatoid odontogenic tumors (AOTs), and six calcifying epithelial odontogenic tumors (CEOTs).

RESULTS

A higher rate of tumor cells strongly positive for Twist was observed in AC compared to the other tumors (P = 0.019). The rate of tumor cells strongly positive for Snail tended to be higher in AC than in AM (P = 0.060). AM and AC showed a higher rate of Twist-positive stromal cells than AOT and CEOT (P < 0.001). Tumor cells of recurrent AM showed stronger expression of Twist (P < 0.001) and Snail (P = 0.001) compared to AM without recurrence. A moderate positive correlation was observed between tumor expression of Twist and Snail (r = 0.376, P = 0.001) and between tumor and stromal expression of Snail (r = 0.334, P = 0.002).

CONCLUSIONS

Twist and Snail may affect the epithelial-mesenchymal transition in AC and be involved in recurrence of AM. Stromal Twist expression may be associated with aggressive clinical behavior of epithelial odontogenic tumors. A Twist-Snail pathway may participate in the development and progression of odontogenic tumors, and tumor-stroma interaction in odontogenic tumors may be mediated by Snail.

Atypical granular cell tumor in the maxilla: The first report of primary intraosseous granular cell tumor

BACKGROUND

Granular cell tumor (GCT) is a benign soft tissue tumor of neural origin and is characterized by eosinophilic granular cells showing positivity for neuronal markers. Herein, we report the first case of primary intraosseous GCT arising in the maxilla of an adolescent girl.

METHODS AND RESULTS

A 16-year-old female patient presented with palatal swelling. Radiographic findings revealed a well-defined radiolucent lesion centrally located in the right maxilla. Mass excision was performed, and histopathologic examination showed sheets and cords of eosinophilic granular cells with cellular pleomorphism. Tumor cells were strongly positive for vimentin, S-100 protein, and CD56, and negative for cytokeratin, desmin, smooth muscle actin, and c-kit. High expression of p53 and Ki-67 was found. The final diagnosis was atypical GCT.

CONCLUSION

When evaluating an intraosseous radiolucent lesion with histopathologic features of granular cells, clinicians and pathologists should include GCT in the differential diagnosis. © 2016 Wiley Periodicals, Inc. Head Neck 38:E2467-E2470, 2016.

Chondrosarcoma of the temporomandibular joint: a case report and review of the literature

OBJECTIVE

Chondrosarcoma is the second most common sarcoma arising in the bone, but it rarely involves the temporomandibular joint (TMJ). To date, 30 cases of TMJ chondrosarcoma have been reported in the English literature, and the authors report an additional case arising from a cystic lesion in a 60-year-old female patient.

CLINICAL PRESENTATION

The clinical and radiological diagnosis of the lesion was initially synovial cyst, and periodic check-ups were done after aspiration of the lesion. After three years, the patient perceived swelling of the lesion, and surgical excision was performed. The final diagnosis was grade I chondrosarcoma.

CONCLUSION

When clinicians detect a cystic lesion in the radiographic imaging of the TMJ, chondrosarcoma should be included in the differential diagnosis. In addition, computed tomography (CT) as well as magnetic resonance imaging (MRI) is recommended for the accurate diagnosis and proper preoperative planning in TMJ chondrosarcoma.

The curative efficacy of arthroscopic therapy in treating anterior cruciate ligament rupture with secondary osteoarthritis

OBJECTIVE

To compare and analyze the clinical effects of arthroscopic therapy and drug therapy in treating anterior cruciate ligament (ACL) rupture with secondary osteoarthritis (OA).

PATIENTS AND METHODS

A total of 68 patients that were diagnosed as ACL rupture with secondary OA in our hospital from February 2014 to February 2015 were enrolled in our study. All of the patients were randomly divided into control group (n = 30) and observation group (n = 38) according to the order of admission. The patients in the control group were given analgesic, anti-inflammatory drugs + functional rehabilitation training whereas the patients in the observation group were given ACL reconstruction + OA debridement and functional rehabilitation training under arthroscopy.

RESULTS

The success rate of the observation group was 92.1%. After 3-month follow-up, the clinical total effective rate of the observation group was significantly higher than that of the control group, the prevalence of complications in the observation group was significantly lower than in the control group, and differences were statistically significant (p < 0.05). Lysholm scale scoring of observation group was significantly higher than of the control group, modified McGill pain scale score was significantly lower than that of the control group, and differences were statistically significant (p < 0.05). Quadriceps muscle peak torque, average power, and the optimal single work at 60°/s, 120°/s, and 180°/s were significantly higher than those of the control group, and differences were statistically significant (p < 0.05).

CONCLUSIONS

Arthroscopic operative therapy was safe and effective for the treatment of ACL with secondary OA. Compared with drug therapy, it can significantly improve the movement function of the knee joint, so it was worthy of clinical application.

Extraocular muscle injury during endoscopic sinus surgery: a series of 10 cases at a single center

BACKGROUND

Extraocular muscle (EOM) injury is a rare but serious complication of endoscopic sinus surgery (ESS). The aim of this study is to describe the clinical characteristics and course of EOM injury occurring during ESS.

DESIGN

Retrospective case series.

METHODS

Medical records and CT images of patients who suffered from EOM injury after ESS between 2006 and 2012 were retrospectively reviewed. Patient demographics, endoscopic anatomy, type of surgery (primary or revision), predisposing risk factors, site and extent of injury on CT imaging, and associated complications were evaluated. In addition, data regarding ophthalmologic management and clinical outcomes were collected.

RESULTS

Ten patients with EOM injuries after ESS were included in this study. One patient was undergoing revision ESS. All patients sustained medial rectus muscle injury and one patient suffered concurrent ipsilateral inferior rectus muscle injury. A microdebrider was used in nine cases. Right-sided injury (90% of patients) was more prevalent than left-sided injury, and 70% of injured medial rectus muscles were completely transected. After subsequent strabismus surgery, 8/9 patients regained binocular single vision in primary gaze despite residual diplopia in some gaze positions.

CONCLUSION

Although proper ophthalmologic surgery after EOM injury may improve deviation in the primary gaze position, none of the patients regained normal EOM movement. Therefore, prevention of this complication through adequate surgical technique and precautions is important.

The role of p300 in the tumor progression of oral squamous cell carcinoma

BACKGROUND

EP300 gene encoding p300 is a candidate tumor suppressor gene. This study investigated p300 expression and gene alteration in oral squamous cell carcinoma (OSCC) specimens to assess its role in OSCC development.

METHODS

Genomic DNA extracted from 13 human OSCC cell lines and 40 OSCC patient specimens was subjected to methylation-specific PCR and exon sequencing. Immunohistochemical staining with primary antibodies against p300 and p53 was performed in 48 patients with OSCC. We analyzed the association between the data and clinicopathological factors of OSCC patients.

RESULTS

Methylation-specific PCR revealed that the EP300 promoter region was not hypermethylated in OSCC. Only one cell line demonstrated a point mutation at exon 31. On immunohistochemical examination, patients with metastatic lymph nodes (P = 0.009) and advanced clinical stage (P = 0.046) tended to show increased expression of p300. There was no statistically significant relationship between p300 expression and p53 accumulation in OSCC tissue samples. Patient survival was not correlated with p300 expression.

CONCLUSIONS

EP300 is not a tumor suppressor gene because there was neither epigenetic inactivation of the gene nor a mutation resulting in functional impairment. Based on p300 overexpression and its association with clinical factors in patients with OSCC, it is likely that p300 itself or one of its target genes plays a key role in the aggressive phenotypes of OSCC.

Intracellular delivery of cell-penetrating peptide-transcriptional factor fusion protein and its role in selective osteogenesis

Protein-transduction technology has been attempted to deliver macromolecular materials, including protein, nucleic acids, and polymeric drugs, for either diagnosis or therapeutic purposes. Herein, fusion protein composed of an arginine-rich cell-penetrating peptide, termed low-molecular-weight protamine (LMWP), and a transcriptional coactivator with a PDZ-binding motif (TAZ) protein was prepared and applied in combination with biomaterials to increase bone-forming capacity. TAZ has been recently identified as a specific osteogenic stimulating transcriptional coactivator in human mesenchymal stem cell (hMSC) differentiation, while simultaneously blocking adipogenic differentiation. However, TAZ by itself cannot penetrate the cells, and thus needs a transfection tool for translocalization. The LMWP-TAZ fusion proteins were efficiently translocalized into the cytosol of hMSCs. The hMSCs treated with cell-penetrating LMWP-TAZ exhibited increased expression of osteoblastic genes and protein, producing significantly higher quantities of mineralized matrix compared to free TAZ. In contrast, adipogenic differentiation of the hMSCs was blocked by treatment of LMWP-TAZ fusion protein, as reflected by reduced marker-protein expression, adipocyte fatty acid-binding protein 2, and peroxisome proliferator-activated receptor-γ messenger ribonucleic acid levels. LMWP-TAZ was applied in alginate gel for the purpose of localization and controlled release. The LMWP-TAZ fusion protein-loaded alginate gel matrix significantly increased bone formation in rabbit calvarial defects compared with alginate gel matrix mixed with free TAZ protein. The protein transduction of TAZ fused with cell-penetrating LMWP peptide was able selectively to stimulate osteogenesis in vitro and in vivo. Taken together, this fusion protein-transduction technology for osteogenic protein can thus be applied in combination with biomaterials for tissue regeneration and controlled release for tissue-engineering purposes.

Abstract A184: Knock-down of Cripto-1 expression by small interfering RNA inhibits growth and migration of oral squamous cell carcinoma cells

Background: Cripto-1, also known as teratocarcinoma-derived growth factor-1 (TDGF-1), is a member of the EGF-CFC family. Cripto-1 has been found to be overexpressed in different human carcinomas, including breast, colon, lung, cervix, stomach, pancreas, and nasopharynx, while it was absent or very low in normal adult tissue. In vitro and in vivo studies have shown that Cripto-1 plays an important oncogenic role during carcinogenesis by promoting cell proliferation, migration, invasion, and tumor angiogenesis, as well as inducing the epithelial-to-mesenchymal transition. In our previous study, we first demonstrated that Cripto-1 protein was significantly overexpressed in oral squamous cell carcinoma (OSCC) tissues than in normal oral mucosa and the exogenous recombinant human Cripto-1 protein induced a significant increase in the cell proliferation and migration of OSCC cell lines (SCC-4 and SCC-25). Our data suggested that Cripto-1 may be involved in the tumorigenesis and progression of OSCC. To validate the value of Cripto-1 as a novel molecular target for OSCC treatment, in the present study, we investigated whether the suppression of endogenous Cripto-1 inhibits the growth and migration of OSCC cells.

Methods: We screened 13 OSCC cell lines to select cell lines with high Cripto-1 expression by RT-PCR and western blot analysis. Among them, KOSCC-33A and HSC4 cell lines were selected and transfected with anti-Cripto-1 siRNA and negative control siRNA. Cell proliferation was evaluated 24h, 48h, and 72h after transfection, and migration assay was also performed 24h and 48h after transfection, with anti-Cripto-1 siRNA and negative control siRNA. Statistical significance was determined using t-test.

Results: The results of RT-PCR analysis revealed that the Cripto-1 mRNA in KOSCC-33A and HSC4 cells were effectively suppressed by anti-Cripto-1 siRNA when compared with cells treated with a negative control siRNA. In the cell proliferation assay, we found that Cripto-1 knock-down induced a significant inhibition of the growth of KOSCC-33A and HSC4 cells (P &lt;0.05). In addition, Cripto-1 knock-down resulted in a significant decrease in the migration of both cell lines (P &lt;0.05).

Conclusion: The present study confirms that Cripto-1 plays an important role in the growth and motility of OSCC cells. Our data also suggest that suppression of Cripto-1 expression may be one of the new strategies for the treatment of OSCC. Further studies are in progress to clarify the signaling pathway underlying the oncogenic effects of Cripto-1 in OSCC.

Citation Information: Mol Cancer Ther 2013;12(11 Suppl):A184.

Citation Format: Ji-Hoon Kim, Young-Ah Cho, Ji-Soo Hong, Eun-Jin Choi, Seong-Doo Hong, Jae-Il Lee, Sam-Pyo Hong, Hye-Jung Yoon. Knock-down of Cripto-1 expression by small interfering RNA inhibits growth and migration of oral squamous cell carcinoma cells. [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2013 Oct 19-23; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2013;12(11 Suppl):Abstract nr A184.

Pain fiber anesthetic reduces brainstem Fos after tooth extraction

We recently demonstrated that pain-sensing neurons in the trigeminal system can be selectively anesthetized by co-application of QX-314 with the TRPV1 receptor agonist, capsaicin (QX cocktail). Here we examined whether this new anesthetic strategy can block the neuronal changes in the brainstem following molar tooth extraction in the rat. Adult male Sprague-Dawley rats received infiltration injection of anesthetic 10 min prior to lower molar tooth extraction. Neuronal activation was determined by immunohistochemistry for the proto-oncogene protein c-Fos in transverse sections of the trigeminal subnucleus caudalis (Sp5C). After tooth extraction, c-Fos-like immunoreactivity (Fos-LI) detected in the dorsomedial region of bilateral Sp5C was highest at 2 hrs (p < .01 vs. naïve ipsilateral) and declined to pre-injury levels by 8 hrs. Pre-administration of the QX cocktail significantly reduced to sham levels Fos-LI examined 2 hrs after tooth extraction; reduced Fos-LI was also observed with the conventional local anesthetic lidocaine. Pulpal anesthesia by infiltration injection was confirmed by inhibition of the jaw-opening reflex in response to electrical tooth pulp stimulation. Our results suggest that the QX cocktail anesthetic is effective in reducing neuronal activation following tooth extraction. Thus, a selective pain fiber 'nociceptive anesthetic' strategy may provide an effective local anesthetic option for dental patients in the clinic.

Plasmablastic lymphoma of the oral cavity in a human immunodeficiency virus-negative patient: a case report with literature review

Plasmablastic lymphoma (PBL) is an aggressive diffuse large B-cell lymphoma variant that is most frequently observed in the oral cavity of human immunodeficiency virus (HIV)-infected individuals. However, in recent years, some cases have emerged in patients without HIV infection and involve other sites like stomach, lung, nasal cavity, and jejunum. We report a rare case of PBL in the maxillary anterior area of a 62-year-old man without HIV infection. The tumor cells were characterized by non-cohesive round or oval shape cells with eccentrically-placed nuclei with a prominent perinuclear halo. Immunohistochemical studies showed that the tumor cells were strongly positive for MUM1, VS38c, VMT, and κ light chain, focally positive for LCA and CD79a, and negative for CD3, CD20, CD56, λ light chain, CK-pan, EMA, and HMB45. The patient was treated with chemotherapy using cyclophosphamide, doxorubicin, vincristine, and prednisone. The lesion showed partial remission.

Hypothetical pathogenesis of eosinophilic infiltration in Langerhans cell histiocytosis of the jaw

OBJECTIVE

The present study investigated the densities of mast cells and CCL-11/eotaxin-1 expression of tumor cells in Langerhans cell histiocytosis (LCH) of the jaw.

STUDY DESIGN

Eleven LCH cases arising in the jaws were selected. We evaluated eotaxin-1 expression in LCH cells via immunohistochemical staining. Toluidine blue was used to stain mast cells, with 20 periapical granuloma specimens serving as the control group.

RESULTS

In all 7 patients with multifocal LCH, jaw lesions were the earliest manifestation. Toluidine blue staining revealed that most of the mast cells involved in LCH were degranulated, and the number of mast cells in LCH lesions was not significantly higher than in periapical granulomas. Upon immunohistochemical examination, all patients but one showed positivity for eotaxin-1 in LCH cells.

CONCLUSION

This preliminary study suggests that eotaxin-1 expression in LCH cells may contribute to eosinophilic infiltration. Further studies of chemokine-receptor interactions will be needed to confirm this.

Comparative immunohistochemical study of ameloblastoma and ameloblastic carcinoma

OBJECTIVE

Ameloblastic carcinoma combines the histologic features of ameloblastoma with cytologic atypia, regardless of whether it has metastasized. Because of its rarity, there are few immunoprofile studies of ameloblastic carcinoma and few comparative studies of ameloblastic carcinoma and ameloblastoma. In this study, we compared the expression levels of cytokeratins (CKs), matrix metalloproteinases (MMPs), and Ki-67 between ameloblastoma and ameloblastic carcinoma, and assessed the usefulness of these markers for differentiating the tumors.

STUDY DESIGN

We assessed CK7, CK14, CK18, CK19, MMP-2, MMP-9, and Ki-67 expression by immunohistochemistry in 10 cases of ameloblastoma and 7 cases of ameloblastic carcinoma and then compared expression patterns between the 2 groups.

RESULTS

Immunostaining for CK14 and CK19 was diffuse and strongly positive in both tumor types, but staining for CK7 was focally positive in only 1 case of ameloblastoma and absent in all cases of ameloblastic carcinoma. However, there was a significant difference in CK18 expression between the 2 tumors (P = .000). Whereas 80% of ameloblastomas showed negative reactivity for CK18, most cases of ameloblastic carcinomas showed a moderate to strong intensity of immunostaining for CK18. Regarding the expression of MMPs, there were significant differences in parenchymal MMP-2 and stromal MMP-9 expression between the 2 tumors. Compared to ameloblastoma, ameloblastic carcinoma showed significantly strong expression of MMP-2 in parenchymal cells (P = .001) and MMP-9 in stromal cells (P = .013). However, there were no differences in MMP-2 expression of stromal cells and MMP-9 expression of parenchymal cells between ameloblastoma and ameloblastic carcinoma. The mean Ki-67 labeling index (LI) of ameloblastic carcinomas was 17.21%, which was significantly higher than that of ameloblastomas (3.57%; P = .002).

CONCLUSIONS

The significant expression of CK18, parenchymal MMP-2, stromal MMP-9, and Ki-67 could provide useful markers for differentiating ameloblastic carcinoma from ameloblastoma.

Relationship between the expressions of PD-L1 and tumor-infiltrating lymphocytes in oral squamous cell carcinoma

Tumor-infiltrating lymphocytes (TILs) are considered to represent immune reactions of the host to a malignant tumor. Programmed death receptor ligand-1 (PD-L1) is a surface protein that blocks the function of T lymphocytes and is expressed on cancer cells. Tumor-associated fibroblasts (TAFs), which influence tumor growth have also been reported to express PD-L1 and thus inhibit TILs. In the present study, we investigated the densities of CD4(+)/CD8(+) TILs, PD-L1 expression of tumor cells and TAFs in oral squamous cell carcinoma (OSCC). Forty-five cases of OSCC were selected. We evaluated PD-L1 expression and the infiltration degree of each lymphocyte by immunohistochemical examination. These data were analyzed in connection with clinicopathological factors. Peritumoral CD8(+) TILs were observed in every patient with OSCC, and their densities were correlated with lymph node metastasis (P<0.001), tumor size (P=0.003), and clinical stage (P<0.001). PD-L1 expression on OSCC cells was observed in 39 cases and was associated with the lower density of intratumoral CD8(+) TILs (P=0.047). PD-L1 expression of tumors <4cm in size was correlated with the histological grade of the tumor (P=0.022). TAFs were positive for PD-L1 in 18 cases. Peritumoral TILs were significantly associated with tumor size, lymph node metastasis and clinical stage. Though PD-L1 expressed by OSCC cells did not affect patients' survival, its correlation with decreased number of intratumoral TILs suggests that the development of a strategy to block the interactions of PD-L1 with TIL would be a useful tool for inhibiting tumor growth.

The role of Cripto-1 in the tumorigenesis and progression of oral squamous cell carcinoma

Oral squamous cell carcinoma (OSCC), the most common malignancy of the oral cavity, remains a lethal disease in over 50% of cases diagnosed annually, due mostly to late detection of this cancer in its advanced stages despite the easy accessibility of the oral cavity for regular examinations. Cripto-1 is a member of the epidermal growth factor (EGF)-CFC protein family and is involved in the activation of several different signaling pathways during embryonic development and cellular transformation. Although the Cripto-1 protein is overexpressed in several human cancers including breast, colon, cervix, gastric, and pancreatic cancer, no prior study has evaluated Cripto-1 expression in OSCC. Therefore, our aims in this study were to examine Cripto-1 expression in clinical samples of OSCC patients using immunohistochemistry, to analyze the correlation between Cripto-1 expression and clinicopathologic parameters, and to identify the oncogenic roles of Cripto-1 in OSCC cell lines. Both epithelial dysplasia (73.3%) and OSCC (55.5%) tissue samples showed significantly higher expression of Cripto-1 than normal mucosa (20%) (p=0.031). In the OSCC samples, there was a significant correlation between Cripto-1 expression and the histological differentiation of OSCC (p=0.015) and a high PCNA index (p=0.011). The in vitro cell proliferation assays demonstrated that recombinant human Cripto-1 (rhCripto-1) induced both SCC-4 and SCC-25 cells to proliferate as compared with control cells (p<0.05 and p<0.01, respectively). In in vitro migration assays, treatment of SCC-4 and SCC-25 cells with rhCripto-1 protein induced a 2.4-fold and 1.7-fold-increase in cell migration, respectively (p=0.000 and p=0.008, respectively). Taken together, our data suggest that Cripto-1 plays a role in the malignant transformation of the oral mucosa and is involved in the tumorigenesis and progression of OSCC by promoting the growth and migration of malignant cells.

Multiple calcifying hyperplastic dental follicles: comparison with hyperplastic dental follicles

BACKGROUND

Multiple calcifying hyperplastic dental follicles (MCHDF) is a rare disorder that is characterized by multiple impacted teeth and enlarged dental follicles that include calcifications. The current lack of information characterizing MCHDF impedes clinicians from making prompt differential diagnoses. We describe five cases of MCHDF and analyze their clinical and histopathological features in an effort to compare MCHDF with hyperplastic dental follicles (HDF) of singly impacted teeth.

METHODS

Our five cases of MCHDF were examined and clinically/histologically compared with data from 50 singly impacted teeth with HDFs.

RESULTS

The five patients described in this study were all male. The pattern of impaction varied, but every second molar was impacted in all the patients. Alterations in the number of teeth, such as supernumerary or congenitally missing teeth were observed. Upon microscopic examination, most of the calcifications consisted of basophilic droplets that were fused to one another, and were surrounded by whirling spindle cells. Another type of calcification that was observed less frequently resembled woven bone. These features were consistent with three previously reported cases and observed in HDFs of 20 singly impacted teeth. While the average period of impaction and the time to reach some level of calcification in MCHDFs was shorter than in single calcifying HDFs, the calcification was more generalized in MCHDFs.

CONCLUSIONS

This study indicates that MCHDF is a separate pathologic entity with exclusive male predilection and earlier calcifications, different to HDF. Further studies are needed to understand the etiology of MCHDFs to provide various options for treatment, and to clarify the mechanisms of eruption.

Spontaneous tumorigenicity of primary human oral keratinocytes with human papillomavirus negativity and impaired apoptosis

Although >60% of oral cancer cases are not related to human papillomavirus (HPV) infection, most studies of oral carcinogenesis in human cells in vitro are carried out with human oral keratinocytes immortalized by HPV DNA. To explore whether human oral keratinocytes can spontaneously transform without HPV infection, we attempted to establish spontaneously immortalized and tumorigenic-transformed human oral keratinocytes by serial subculture to the post-mitotic stage. Here we report two spontaneously transformed human oral keratinocyte lines from adult human gingival samples. These lines were obviously immortal (>140 passages) and transformed phenotypes in vitro. One of the lines, Spi-HOK1, remained non-tumorigenic in nude mice, whereas the other line, Spt-HOK80, showed tumorigenicity. These lines showed epithelial origi-nality, but did not contain high-risk types of HPV DNAs. On karyotyping, Spi-HOK1 was aneuploid with a unique stable marker chromosome. Both cell lines revealed a mutation in the p53 gene, loss of p21WAF1/Cip1 and overexpression of p-Rb-Ser807/811. These cell lines were resistant to cisplatin-induced apoptosis by suppressing induction of apoptotic proteins. These results clearly demonstrate that spontaneous immortalization and spontaneous tumorigenic transformation of primary human oral keratinocytes can occur in vitro without HPV infection and are associated with chromosomal alterations, p53 mutation and impaired apoptosis. To our knowledge, this is the first report demonstrating that the Spi-HOK1 and Spt-HOK80 lines are novel cell lines that are spontaneously transformed from primary human oral keratinocytes.

The effect of a laminin-5-derived peptide coated onto chitin microfibers on re-epithelialization in early-stage wound healing

Considerable effort has been directed towards regenerating defective tissues using tissue-engineering methods. Recently, peptides have been recognized as a valuable scientific tool in the field of tissue-engineering. The PPFLMLLKGSTR motif of the human laminin-5 alpha3 chain has been previously reported to promote keratinocyte survival; however, the in vivo effects of the PPFLMLLKGSTR motif have not yet been studied. These studies raised the hypothesis that a laminin-5-derived peptide can promote wound healing by accelerating re-epithelialization in vivo. To examine this hypothesis, we applied chitin microfibrous matrices coated with the PPFLMLLKGSTR motif in both rat and rabbit full-thickness cutaneous wound models. Compared with vehicle-treated and peptide-treated cutaneous wounds, the application significantly promoted early-stage wound healing by accelerating re-epithelialization, notably reduced inflammatory cell infiltration, and prominently enhanced fibroblast proliferation. These findings support our hypothesis that the PPFLMLLKGSTR motif acts as a very effective wound healing accelerator by enhancing re-epithelialization.