Retrospective analysis of odontogenic myxoma and odontogenic myxofibroma in the oral and maxillofacial region: a fibrous tissue-related differentiation.

The clinical differences between odontogenic myxoma (OM) and odontogenic myxofibroma (OMF), and the clinical significance of their classifications, remain unclear. This study reviewed the clinicopathological characteristics of patients with OM or OMF and evaluated the fibrous component of the specimens. Medical records of 21 patients with OM or OMF who underwent tumour resection were reviewed. The percentage of fibrous tissue on the representative sections was evaluated using haematoxylin and eosin- and Masson's trichrome-stained specimens. Histopathological diagnoses included 11 OMs and 10 OMFs with no tumour recurrence except for two cases in which the dredging method was applied. More cortical bone perforation was observed in OM than in OMF cases, without significant differences. Location-locularity and apparent diffusion coefficient value (ADC)-cortical bone perforation were significantly correlated in all OM and OMF cases. The percentage of fibrous tissue in specimens showed bimodal distribution bordered by 45%. There was a significant association between diagnosis based on 45% fibrous tissue criterion and the final pathological diagnosis. Our study showed a tendency for cortical bone perforation in OM compared to OMF and correlation between ADC and cortical bone perforation. According to the histopathological analyses, the fibrous component of each case was bimodal with 45%, which may be a criterion to distinguish between OM and OMF. Accumulating knowledge, such as significant differences in prognosis, may allow for minimal surgical treatment options based on the diagnosis according to this novel histopathological criterion.

NF1 with 47,XYY mosaicism diagnosed by mandibular neurofibromas.

Neurofibromatosis type 1 (NF1) is an autosomal dominant nevus disease characterized by multiple manifestations, primarily café-au-lait macules and neurofibromas. Here, we present the case of an NF1 patient with 47,XYY mosaicism whose diagnosis was prompted by café-au-lait macules on the skin and mandibular neurofibromas. Targeted next-generation sequencing of the patient's blood sample revealed a novel frameshift mutation in NF1 (NM_000267.3:c.6832dupA:p.Thr2278Asnfs*8) that is considered a pathogenic variant.

Radiotherapy Plus Cetuximab for Squamous Cell Carcinoma of the Oral Cavity: A Multicenter Retrospective Study of 79 Patients in Japan.

There are a few reports that focus on radiotherapy (RT) and cetuximab (CET) therapy exclusively for oral cancer. This retrospective study aimed to investigate the efficacy and safety of RT and CET therapy for locally advanced (LA) or recurrent/metastatic (R/M) oral squamous cell carcinoma (OSCC). Seventy-nine patients from 13 hospitals who underwent RT and CET therapy for LA or R/M OSCC between January 2013 and May 2015 were enrolled in the study. Response, overall survival (OS), disease-specific survival (DSS), and adverse events were investigated. The completion rate was 62/79 (78.5%). The response rates in patients with LA and R/M OSCC were 69% and 37.8%, respectively. When only completed cases were examined, the response rates were 72.2% and 62.9%, respectively. The 1- and 2-year OS were 51.5% and 27.8%, respectively (median, 14 months), for patients with LA OSCC, and 41.5% and 11.9% (median, 10 months) for patients with R/M OSCC. The 1- and 2-year DSS were 61.8% and 33.4%, respectively (median, 17 months), for patients with LA OSCC, and 76.6% and 20.4% (median, 12 months) for patients with R/M OSCC. The most common adverse event was oral mucositis (60.8%), followed by dermatitis, acneiform rash, and paronychia. The completion rate was 85.7% in LA patients and 70.3% in R/M patients. The most common reason for noncompletion was an inadequate radiation dose due to worsening general conditions in R/M patients. Although the standard treatment for LA or R/M oral cancer is concomitant RT with high-dose cisplatin (CCRT) and the efficacy of RT and CET therapy for oral cancer is not considered to be as high as that for other head and neck cancers, it was thought that RT and CET therapy could be possible treatments for patients who cannot use high-dose cisplatin.

Retrospective analysis of schwannoma in the oral and maxillofacial region: clinicopathological characteristics and specific pathology of ancient change.

Schwannomas are benign tumours that originate from the Schwann cells of the nerve. Despite the frequency of their occurrence in the head and neck, data relating to their clinicopathological features in the region are limited. This study reviews the clinicopathological characteristics and specific pathology of ancient (degenerative) change in 40 cases in the oral and maxillofacial region. Medical records were reviewed of the 40 cases treated at Tokyo Medical and Dental University Hospital Faculty of Dentistry between 2000 and 2020. The most frequently involved site was the tongue, and the average tumour size was 13.2 mm. Degenerative changes were observed in eight cases. All tumours were completely excised through biopsy or local excision, and no recurrence was observed on clinical follow up. Statistical analyses revealed significant associations (p < 0.05) between ancient change and tumour size, and between ancient change and the apparent diffusion coefficient (ADC) value derived from diffusion-weighted magnetic resonance imaging (MRI). Analysis suggests that schwannoma progresses over a long period and subsequently undergoes secondary ancient changes. Pathological events such as cystic formation and haemorrhage that are associated with ancient changes, cause hypocellularity and lead to high ADC values. These values may indicate ancient change and should be considered when distinguishing schwannoma from other lesions.

Detection of novel fusion genes by next-generation sequencing-based targeted RNA sequencing analysis in adenoid cystic carcinoma of head and neck.

OBJECTIVE: Adenoid cystic carcinoma (AdCC) is a rare, indolent salivary gland tumor that is reported to be driven by fusion genes. However, MYB/MYBL1-NFIB fusions have been detected in <60% of all AdCC cases and the oncogenic driver mutations in approximately 40% of AdCC remain unknown. Our aim was to identify novel gene fusions in AdCC. STUDY DESIGN: We investigated 20 AdCC cases using a targeted RNA sequencing panel to identify gene fusions and performed quantitative real-time reverse transcription polymerase chain reaction to assess MYB, MYBL1, and NFIB expression levels. RESULTS: A total of 36 fusion transcripts in 15 cases were detected and validated by Sanger sequencing. The MYB-NFIB and MYBL1-NFIB fusion genes were detected in 9 and 3 cases, respectively, in a mutually exclusive manner. Furthermore, novel gene fusions, namely, NFIB-EPB41L2, MAP7-NFIB, NFIB-MCMDC2, MYBL1-C8orf34, C8orf34-NFIB, and NFIB-CASC20, were identified. Among them, NFIB-EPB41L2 and NFIB-MCMDC2 are thought to activate MYB and MYBL1 expression, respectively, through the insertion of a genomic segment in proximity to MYB and MYBL1 genes, respectively. CONCLUSION: Six novel gene fusions other than MYB/MYBL1-NFIB were identified. The detection of novel fusion genes and investigation of the molecular mechanism will contribute to the development of novel molecular targeted therapies for this disease.

Localizing the nerve to the mylohyoid using the mylohyoid triangle.

The nerve to the mylohyoid muscle has been well studied but there are no specific anatomical landmarks for identifying it. Therefore, we aimed to identify anatomical landmarks for localizing the nerve to the mylohyoid muscle in the submandibular region. Sixteen sides from eight embalmed Caucasian cadaveric heads were used in this study. The mean age at the time of death of the specimens was 80.3 years. The anterior and posterior bellies of the digastric muscle, submental artery, and mylohyoid muscle were dissected to verify their relationships with the nerve to the mylohyoid muscle. The nerve to the mylohyoid muscle was found medial to the submental artery, lateral to the anterior belly of the digastric muscle, and anterior to the posterior border of the mylohyoid muscle on all sides. Herein, we identified what we term the mylohyoid triangle. This anatomical region can help localize the nerve to the mylohyoid muscle.

Migration and proliferation of cancer cells in culture are differentially affected by molecular size of modified citrus pectin.

While chemically and thermally modified citrus pectin (MCP) has already been studied for health benefits, it is unknown how size-fractionated oligo- and polysaccharides differentially affect cancer cell behavior. We produced thermally MCP and fractionated it by molecular size to evaluate the effect these polymers have on cancer cells. MCP30/10 (between 30 and 10 kDa) had more esterified homogalacturonans (HG) and fewer rhamnogalacturonans (RG-I) than MCP and MCP30 (higher than 30 kDa), while MCP10/3 (between 10 and 3 kDa) showed higher amounts of type I arabinogalactans (AGI) and lower amounts of RG-I. MCP3 (smaller than 3 kDa) presented less esterified HG and the lowest amount of AGI and RG-I. Our data indicate that the enrichment of de-esterified HG oligomers and the AGI and RG-I depletions in MCP3, or the increase of AGI and loss of RGI in MCP30/10, enhance the anticancer behaviors by inhibiting migration, aggregation, and proliferation of cancer cells.

Ripening-induced chemical modifications of papaya pectin inhibit cancer cell proliferation.

Papaya (Carica papaya L.) is a fleshy fruit with a rapid pulp softening during ripening. Ripening events are accompanied by gradual depolymerization of pectic polysaccharides, including homogalacturonans, rhamnogalacturonans, arabinogalactans, and their modified forms. During intermediate phases of papaya ripening, partial depolymerization of pectin to small size with decreased branching had enhanced pectin anti-cancer properties. These properties were lost with continued decomposition at later phases of ripening. Pectin extracted from intermediate phases of papaya ripening markedly decreased cell viability, induced necroptosis, and delayed culture wound closing in three types of immortalized cancer cell lines. The possible explanation for these observations is that papaya pectins extracted from the third day after harvesting have disrupted interaction between cancer cells and the extracellular matrix proteins, enhancing cell detachment and promoting apoptosis/necroptosis. The anticancer activity of papaya pectin is dependent on the presence and the branch of arabinogalactan type II (AGII) structure. These are first reports of AGII in papaya pulp and the first reports of an in vitro biological activity of papaya pectins that were modified by natural action of ripening-induced pectinolytic enzymes. Identification of the specific pectin branching structures presents a biological route to enhancing anti-cancer properties in papaya and other climacteric fruits.

Galectin-3 Cleavage Alters Bone Remodeling: Different Outcomes in Breast and Prostate Cancer Skeletal Metastasis.

Management of bone metastasis remains clinically challenging and requires the identification of new molecular target(s) that can be therapeutically exploited to improve patient outcome. Galectin-3 (Gal-3) has been implicated as a secreted factor that alters the bone microenvironment. Proteolytic cleavage of Gal-3 may also contribute to malignant cellular behaviors, but has not been addressed in cancer metastasis. Here, we report that Gal-3 modulates the osteolytic bone tumor microenvironment in the presence of RANKL. Gal-3 was localized on the osteoclast cell surface, and its suppression by RNAi or a specific antagonist markedly inhibited osteoclast differentiation markers, including tartrate-resistant acid phosphatase, and reduced the number of mature osteoclasts. Structurally, the 158-175 amino acid sequence in the carbohydrate recognition domain (CRD) of Gal-3 was responsible for augmented osteoclastogenesis. During osteoclast maturation, Gal-3 interacted and colocalized with myosin-2A along the surface of cell-cell fusion. Pathologically, bone metastatic cancers expressed and released an intact form of Gal-3, mainly detected in breast cancer bone metastases, as well as a cleaved form, more abundant in prostate cancer bone metastases. Secreted intact Gal-3 interacted with myosin-2A, leading to osteoclastogenesis, whereas a shift to cleaved Gal-3 attenuated the enhancement in osteoclast differentiation. Thus, our studies demonstrate that Gal-3 shapes the bone tumor microenvironment through distinct roles contingent on its cleavage status, and highlight Gal-3 targeting through the CRD as a potential therapeutic strategy for mitigating osteolytic bone remodeling in the metastatic niche.

Extracellular galectin-3 programs multidrug resistance through Na+/K+-ATPase and P-glycoprotein signaling.

Galectin-3 (Gal-3, LGALS3) is a pleotropic versatile, 29-35 kDa chimeric gene product, and involved in diverse physiological and pathological processes, including cell growth, homeostasis, apoptosis, pre-mRNA splicing, cell-cell and cell-matrix adhesion, cellular polarity, motility, adhesion, activation, differentiation, transformation, signaling, regulation of innate/adaptive immunity, and angiogenesis. In multiple diseases, it was found that the level of circulating Gal-3 is markedly elevated, suggesting that Gal-3-dependent function is mediated by specific interaction with yet an unknown ubiquitous cell-surface protein. Recently, we showed that Gal-3 attenuated drug-induced apoptosis, which is one of the mechanisms underlying multidrug resistance (MDR). Here, we document that MDR could be mediated by Gal-3 interaction with the house-keeping gene product e.g., Na+/K+-ATPase, and P-glycoprotein (P-gp). Gal-3 interacts with Na+/K+-ATPase and induces the phosphorylation of P-gp. We also find that Gal-3 binds P-gp and enhances its ATPase activity. Furthermore Gal-3 antagonist suppresses this interaction and results in a decrease of the phosphorylation and the ATPase activity of P-gp, leading to an increased sensitivity to doxorubicin-mediated cell death. Taken together, these findings may explain the reported roles of Gal-3 in diverse diseases and suggest that a combined therapy of inhibitors of Na+/K+-ATPase and Gal-3, and a disease specific drug(s) might be superior to a single therapeutic modality.

Gp78, an E3 ubiquitin ligase acts as a gatekeeper suppressing nonalcoholic steatohepatitis (NASH) and liver cancer.

Nonalcoholic steatohepatitis (NASH) is related to metabolic dysregulation and the perturbation of endoplasmic reticulum (ER) homeostasis that frequently develops into hepatocellular carcinoma (HCC). Gp78 is E3 ligase, which regulates endoplasmic reticulum-associated degradation (ERAD) by ubiquitinylation of misfolded ER proteins. Here, we report that upon ageing (12 months), gp78-/- mice developed obesity, recapitulating age-related human NASH. Liver histology of gp78-/- mice revealed typical steatosis, hepatic inflammation and fibrosis, followed by progression to hepatocellular tumors. Acute ER stress revealed that loss of gp78 results in up regulation of unfolded protein response (UPR) pathways and SREBP-1 regulating de novo lipogenesis, responsible for fatty liver. Tissue array of human hepatocellular carcinoma (HCC) demonstrated that the expression of gp78 was inversely correlated with clinical grades of cancer. Here, we have described the generation of the first preclinical experimental model system which spontaneously develops age-related NASH and HCC, linking ERAD to hepatosteatosis, cirrhosis, and cancer. It suggests that gp78 is a regulator of normal liver homeostasis and a tumor suppressor in human liver.

Galectin-3 leads to attenuation of apoptosis through Bax heterodimerization in human thyroid carcinoma cells.

Cancer cells survive escaping normal apoptosis and the blocks in apoptosis that keep cancer cells alive are promising candidates for targeted therapy. Galectin-3 (Gal-3) is, a member of the lectin family, which is involved in cell growth, adhesion, proliferation and apoptosis. It remains elusive to understand the role of Gal-3 on apoptosis in thyroid carcinoma cells. Here, we report that Gal-3 heterodimerizes Bax, mediated by the carbohydrate recognition domain (CRD) of Gal-3, leading to anti-apoptotic characteristic. Gal-3/Bax interaction was suppressed by an antagonist of Gal-3, in which in turn cells became sensitive to apoptosis. The data presented here highlight that Gal-3 is involved in the anti-apoptosis of thyroid carcinoma cells. Thus, it suggests that targeting Gal-3 may lead to an improved therapeutic modality for thyroid cancer.

Galectin-3 inhibits osteoblast differentiation through notch signaling.

Patients with bone cancer metastasis suffer from unbearable pain and bone fractures due to bone remodeling. This is caused by tumor cells that disturb the bone microenvironment. Here, we have investigated the role of tumor-secreted sugar-binding protein, i.e., galectin-3, on osteoblast differentiation and report that it downregulates the expression of osteoblast differentiation markers, e.g., RUNX2, SP7, ALPL, COL1A1, IBSP, and BGLAP, of treated human fetal osteoblast (hFOB) cells. Co-culturing of hFOB cells with human breast cancer BT-549 and prostate cancer LNCaP cells harboring galectin-3 has resulted in inhibition of osteoblast differentiation by the secreted galectin-3 into culture medium. The inhibitory effect of galectin-3 was found to be through its binding to Notch1 in a sugar-dependent manner that has led to accelerated Notch1 cleavage and activation of Notch signaling. Taken together, our findings show that soluble galectin-3 in the bone microenvironment niche regulates bone remodeling through Notch signaling, suggesting a novel bone metastasis therapeutic target.

miR-655 Is an EMT-suppressive microRNA targeting ZEB1 and TGFBR2.

Recently, the epithelial-to-mesenchymal transition (EMT) has been demonstrated to contribute to normal and disease processes including cancer progression. To explore EMT-suppressive microRNAs (miRNAs), we established a cell-based reporter system using a stable clone derived from a pancreatic cancer cell line, Panc1, transfected with a reporter construct containing a promoter sequence of CDH1/E-cadherin in the 5' upstream region of the ZsGreen1 reporter gene. Then, we performed function-based screening with 470 synthetic double-stranded RNAs (dsRNAs) mimicking human mature miRNAs using the system and identified miR-655 as a novel EMT-suppressive miRNA. Overexpression of miR-655 not only induced the upregulation of E-cadherin and downregulation of typical EMT-inducers but also suppressed migration and invasion of mesenchymal-like cancer cells accompanied by a morphological shift toward the epithelial phenotype. In addition, we found a significant correlation between miR-655 expression and a better prognosis in esophageal squamous cell carcinoma (ESCC). Moreover, ZEB1 and TGFBR2, which are essential components of the TGF-b signaling pathway, were identified as direct targets of miR-655, suggesting that the activation of the TGF-b-ZEB1-E-cadherin axis by aberrant downregulation of miR-655 may accelerate cancer progression.