Spatiotemporal characteristics of tissue derived small extracellular vesicles is associated with tumor relapse and anti-PD-1 response.

Small extracellular vesicles (sEVs) residing at tumor tissues are valuable specimens for biopsy. Tumor heterogeneity is common across all cancer types, but the heterogeneity of tumor tissue-derived sEVs (Ti-sEVs) is undefined. This study aims to discover the spatial distributions of Ti-sEVs in oral squamous cell carcinoma (OSCC) tissues and explore how these vesicle distributions affect the patients' prognosis. Multi-regional sampling enabled us to uncover that Ti-sEVs' accumulation at peritumoral sites correlates with a higher disease-free survival rate, and conversely, sparse peritumoral Ti-sEVs tend to forecast a higher risk of relapse. Of those relapsed patients, Ti-sEVs strongly bind to extracellular matrix and subsequently degrade it for allowing themselves enter the bloodstream rather than staying in situ. In advanced OSCC patients, the quantity and spatial distribution of Ti-sEVs prior to anti-PD-1 treatment, as well as the temporal variance of Ti-sEVs before and after immunotherapy, strongly map the clinical response and can help to distinguish the patients with shrinking tumors from those with growing tumors. Our work elucidates the correlation of spatiotemporal features of Ti-sEVs with patients' therapeutic outcomes and exhibit the potential for using Ti-sEVs as a predictor to forecast prognosis and screen the responders to anti-PD-1 therapy.

A retrospective study of the malignant change of odontogenic keratocyst.

The odontogenic keratocyst (OKC) is a common cystic lesion of the maxilla and mandible. Squamous cell carcinoma (SCC) arising from OKC or dysplasia occurring in OKC is rare. This study aimed to explore the incidence and clinical features of the dysplasia and malignant transformation of OKC. In this study, 544 patients diagnosed with OKC were collected. Among them, 3 patients were diagnosed as SCC arising from OKC, and 12 patients were diagnosed as OKC with dysplasia. The incidence was calculated. Clinical features were analyzed by chi-square test. In addition, a representative case reconstructing mandible with vascularized fibula flap under general anesthesia was reported. And cases reported before were reviewed. The incidence of the dysplasia and malignant transformation of OKC, which are highly associated with the clinical features of swelling and chronic inflammation, is about 2.76%. But the relevance between the dysplasia and malignant transformation and age, gender together with pain is not statistically high. All in all, the clinical features of swelling and chronic inflammation can be considered as characteristics of the dysplasia and malignant transformation of OKC. Although the pain isn't statistically relevant, it may be a dangerous clew. Also, combined with earlier literatures, the dysplasia and malignant transformation of OKC shows unique features of radiographs and histopathology.

Watching Food Videos Leads to Postparotidectomy Salivary Fistula.

Salivary fistula is a common postparotidectomy complication, and eating sour or spicy food ranks among the leading causes. Here we report a rare postparotidectomy salivary fistula case, a 31-year-old female patient who affirmed that she did not eat any irritating foods but admitted that she had been watching food videos for up to 4 hours every day since she left hospital. This case offers a cautionary tale about postparotidectomy precautions.

Myofascial iliac crest flap for reconstruction of combined oral mucosa-mandibular defects: A single-centre experience.

BACKGROUND: Deep circumflex iliac artery (DCIA) myofascial iliac crest flap has been used for combined oral mucosa-mandibular defects reconstruction. The bone component of this composite flap can reconstruct the mandible with superior contour match, and the muscle fascia which used for repairing the oral mucosa defect will transform into an oral mucosa-like appearance. To explore its scope of clinical application and how the fascia transformed into oral mucosa will give surgeons flexibility to reconstruct the combined oral mucosa-mandibular defects. METHODS: A retrospective review of 18 patients who received combined oral mucosa-mandibular defects reconstruction with DCIA myofascial iliac crest flaps from Dec 2016 to Dec 2020 was performed. The characteristics of the mandibular defects and the flaps were recorded. The postoperative dynamic changes of one graft's fascia were observed from serial photographs. RESULTS: All myofascial iliac crest flaps survived successfully. The bone grafts were from 4.0 to 9.5 cm (mean 7.6 ± 1.5 cm) in length and from 2.0 to 3.5 cm (mean 2.7 ± 0.4 cm) in height. The sizes of fascia were from 13.5 to 48.0 cm2 (mean 27.2 ± 9.4 cm2). The grafted fascia firstly changed into a yellow pseudomembrane-like appearance, and then experienced muscle oedema before finally transformed into an oral mucosa-like appearance at about 60 days after operation. CONCLUSION: Myofascial iliac crest flap is a good option for reconstruction of combined oral mucosa-mandibular defects because of its excellent bone and oral mucosa matches.

Increased salivary microvesicles are associated with the prognosis of patients with oral squamous cell carcinoma.

Microvesicles (MVs), which are cell-derived membrane vesicles present in body fluids, are closely associated with the development of malignant tumours. Saliva, one of the most versatile body fluids, is an important source of MVs. However, the association between salivary MVs (SMVs) and oral squamous cell carcinoma (OSCC), which is directly immersed in the salivary milieu, remains unclear. SMVs from 65 patients with OSCC, 21 patients with oral ulcer (OU), and 42 healthy donors were purified, quantified and analysed for their correlations with the clinicopathologic features and prognosis of OSCC patients. The results showed that the level of SMVs was significantly elevated in patients with OSCC compared to healthy donors and OU patients. Meanwhile, the level of SMVs showed close correlations with the lymph node status, and the clinical stage of OSCC patients. Additionally, the ratio of apoptotic to non-apoptotic SMVs was significantly decreased in OSCC patients with higher pathological grade. Consistently, poorer overall survival was observed in patients with lower ratio of apoptotic to non-apoptotic SMVs. In conclusion, the elevated level of SMVs is associated with clinicopathologic features and decreased survival in patients with OSCC, suggesting that SMVs are a potential biomarker and/or regulator of the malignant progression of OSCC.

Osteoradionecrosis of the Zygoma.

Osteoradionecrosis occurs in 4.74% to 37.5% of patients following radiation therapy for head and neck cancer. Osteoradionecrosis mostly happens in the mandible but seldom occurs in other maxillofacial bones. Here, the authors reported a rare case of zygomatic osteoradionecrosis which occurred after maxillectomy and then radiotherapy because of maxillary myoepithelial carcinoma. After resection of zygoma sequestrum, the defect was repaired with forehead flap and healed uneventfully.

A Double-Lobe Flap Design Combined Nasolabial Advancement and Infraorbital Rotation for Reconstruction of Infraorbital Defect.

Various adjacent flaps have been designed to close infraorbital defect, and each of them is trying to get an aesthetic outcome and meanwhile circumvent eyelid retraction, ectropion, and functional disability. Here, the authors report an adjacent double-lobe flap, which took advantage of nasolabial advancement and infraorbital rotation of the 2 lobes, combinatorially closed a pentagon infraorbital defect by removal of 2 small skin paddles as donor sites, and finally yielded an acceptable aesthetic and functional outcome. This flap may be a new option for closure of polygon infraorbital defects.

M2-polarized macrophages in keratocystic odontogenic tumor: relation to tumor angiogenesis.

The purpose of this study was to evaluate the presence of M2-polarized macrophages and their relationships to angiogenesis in keratocystic odontogenic tumor (KCOT). M2-polarized macrophages were detected in KCOT samples by immunohistochemistry and immunofluorescence. Meanwhile, microvessel density measured with antibody against CD31 was closely correlated with the presence of M2-polarized macrophages. In addition, macrophage colony-stimulating factor (M-CSF) significantly contributed to the activation of M2-polarized macrophages. Moreover, the results of in vitro wound healing, cell migration and tube formation assays further revealed the pro-angiogenic function of M2-polarized macrophage-like cells. This function might be associated with secretion of angiogenic cytokines, such as vascular endothelial growth factor (VEGF), transforming growth factor-ß (TGF-ß) and matrix metalloprotein-9 (MMP-9). This study demonstrates for the first time that M2-polarized macrophages are prevalent in KCOT, and their presence is dependent on M-CSF expression. More importantly, these tumor-supportive cells can also promote tumor angiogenesis by secreting angiogenic cytokines.

Down-regulation of connexin43 and connexin32 in keratocystic odontogenic tumours: potential association with clinical features.

AIMS: The objective of this study was to explore the potential involvement of connexin43 (Cx43) and connexin32 (Cx32), two vital members of the connexin families, in the pathogenesis of keratocystic odontogenic tumours (KCOT). METHODS AND RESULTS: The expression levels of Cx43 and Cx32 in human KCOT and normal oral mucosa (OM) tissues were measured using immunohistochemistry and real-time quantitative polymerase chain reaction (qPCR). The relationship between Cx43 and Cx32 expression and markers of proliferation [proliferating cell nuclear antigen (PCNA), cyclin D1], anti-apoptosis [B cell lymphoma 2 (Bcl-2)] and autophagy [light chain 3 (LC3), Sequestosome 1 p62 (p62)] was then investigated in the KCOT samples. The results showed that Cx43 and Cx32 expression was down-regulated significantly in KCOT samples relative to OM samples. Meanwhile, the expression levels of Cx43 and Cx32 were correlated negatively with the expression levels of PCNA, cyclin D1, Bcl-2, LC3 and p62, as confirmed further by double-labelling immunofluorescence analyses. CONCLUSIONS: This study reveals for the first time that Cx43 and Cx32 are down-regulated in KCOT and suggests an association with growth regulation, anti-apoptosis and autophagy in KCOT.

Clinical analysis of 194 cases of head and neck hamartoma.

OBJECTIVE: The aim of this study was to analyze the clinical management of hamartomas in the head and neck region (HNH). STUDY DESIGN: From January 1996 to December 2011, a retrospective analysis of 194 patients with HNH was performed. The preoperative examinations, surgical treatment, and prognosis were recorded and analyzed. RESULTS: Of the 194 patients, 107 were male and 87 female. Their ages ranged from 1 month to 82 years with a mean of 33 years. The most common locations were the oral mucosa (68.6%) and head and neck skin (27.3%). The course of disease ranged from 1 to 264 months with a mean of 66 months. Routine laboratory examinations were within normal limits. All patients underwent surgical removal of the lesions and prognosis was good. CONCLUSIONS: The clinical characteristics of HNH are not specific, and the clinical manifestation is always the same for benign tumors. The first choice of treatment is surgical excision, which results in a good prognosis.

MicroRNAs: new actors in the oral cancer scene.

MicroRNAs (miRNAs) are a group of endogenous, non-coding, 18-24 nucleotide length single-strand RNAs that mediate gene expression at the post-transcriptional level through mRNA degradation or translational repression. They are involved in regulating diverse cellular biological processes such as cell cycle, differentiation and apoptosis. Deregulation of miRNAs affects normal biological processes leading to malignancies, including oral squamous cell carcinoma (OSCC). Recent studies have identified aberrant miRNA expression profiles in OSCC tissues and/or cell lines compared with matched normal controls, the mechanisms of which are becoming unveiled. In addition, a small number of dysregulated miRNAs have been implicated either as oncogenes or tumor suppressors, affecting the initiation and progression of OSCC through the regulation of proliferation, apoptosis, metastasis and chemoresistance. Also, these missexpressed miRNAs have been shown to have potential as novel diagnostic, prognostic and therapeutic tools, which are expected to advance the clinical management of OSCC in the near future.