Role of O-linked N-acetylglucosamine protein modification in oxidative stress-induced autophagy: a novel target for bone remodeling.

O-linked N-acetylglucosamine protein modification (O-GlcNAcylation) is a dynamic post-translational modification (PTM) involving the covalent binding of serine and/or threonine residues, which regulates bone cell homeostasis. Reactive oxygen species (ROS) are increased due to oxidative stress in various pathological contexts related to bone remodeling, such as osteoporosis, arthritis, and bone fracture. Autophagy serves as a scavenger for ROS within bone marrow-derived mesenchymal stem cells, osteoclasts, and osteoblasts. However, oxidative stress-induced autophagy is affected by the metabolic status, leading to unfavorable clinical outcomes. O-GlcNAcylation can regulate the autophagy process both directly and indirectly through oxidative stress-related signaling pathways, ultimately improving bone remodeling. The present interventions for the bone remodeling process often focus on promoting osteogenesis or inhibiting osteoclast absorption, ignoring the effect of PTM on the overall process of bone remodeling. This review explores how O-GlcNAcylation synergizes with autophagy to exert multiple regulatory effects on bone remodeling under oxidative stress stimulation, indicating the application of O-GlcNAcylation as a new molecular target in the field of bone remodeling.

O-GlcNAcylation: roles and potential therapeutic target for bone pathophysiology.

O-linked N-acetylglucosamine (O-GlcNAc) protein modification (O-GlcNAcylation) is a critical post-translational modification (PTM) of cytoplasmic and nuclear proteins. O-GlcNAcylation levels are regulated by the activity of two enzymes, O-GlcNAc transferase (OGT) and O­GlcNAcase (OGA). While OGT attaches O-GlcNAc to proteins, OGA removes O-GlcNAc from proteins. Since its discovery, researchers have demonstrated O-GlcNAcylation on thousands of proteins implicated in numerous different biological processes. Moreover, dysregulation of O-GlcNAcylation has been associated with several pathologies, including cancers, ischemia-reperfusion injury, and neurodegenerative diseases. In this review, we focus on progress in our understanding of the role of O-GlcNAcylation in bone pathophysiology, and we discuss the potential molecular mechanisms of O-GlcNAcylation modulation of bone-related diseases. In addition, we explore significant advances in the identification of O-GlcNAcylation-related regulators as potential therapeutic targets, providing novel therapeutic strategies for the treatment of bone-related disorders.

Functional significance of O-linked N-acetylglucosamine protein modification in regulating autophagy.

Autophagy is a core molecular pathway that preserves cellular and organismal homeostasis. Being susceptible to nutrient availability and stress, eukaryotic cells recycle or degrade internal components via membrane transport pathways to provide sustainable biological molecules and energy sources. The dysregulation of this highly conserved physiological process has been strongly linked to human disease. Post-translational modification, a mechanism that regulates protein function, plays a crucial role in autophagy regulation. O-linked N-acetylglucosamine protein modification (O-GlcNAcylation), a monosaccharide post-translational modification of intracellular proteins, is essential in nutritional and stress regulatory mechanisms. O-GlcNAcylation has emerged as an essential regulatory mechanism of autophagy. It regulates autophagy throughout its lifetime by targeting the core components of the autophagy regulatory network. This review provides an overview of the O-GlcNAcylation of autophagy-associated proteins and their regulation and function in the autophagy pathway. Therefore, this article may contribute to further understanding of the role of O-GlcNAc-regulated autophagy and provide new perspectives for the treatment of human diseases.

The clinicopathological significance and prognostic value of PD-L1 in oral squamous cell carcinoma.

OBJECTIVE: To investigate the relationship between the expression of PD-L1 in OSCC and the clinicopathological features and prognosis of patients. METHODS: We retrospectively analyzed the clinicopathological data and prognosis of 381 OSCC patients. Immunohistochemical staining was performed on OSCC tumor specimens, and the expression level of PD-L1 was evaluated according to the combined positive score (CPS). Kaplan-Meier analysis was used to identify the effect of PD-L1 expression and clinicopathological features on the prognosis of patients. Univariate and multivariate Cox regression analyses were conducted to determine the hazard factors affecting the prognosis of patients. RESULTS: PD-L1 overexpression was significantly associated with cervical lymph node metastasis (p = 0.018), worse clinical stage (p = 0.022), worse tumor differentiation (p = 0.046), and worse depth of invasion (DOI) (p = 0.003). Poorer clinical stage and degree of tumor differentiation were significantly associated with poorer OS and DSS in patients. PD-L1 expression was not associated with prognosis in patients with OSCC. CONCLUSIONS: High PD-L1 expression was significantly associated with higher tumor malignancy in OSCC patients. Poorer clinical stage and degree of tumor differentiation were associated with poor prognosis in OSCC patients. Our results may help clinicians develop more appropriate individualized treatment strategies for their patients, thus improving their outcomes.

Reduction of the exchangeable cadmium content in soil by appropriately increasing the maturity degree of organic fertilizers.

To enhance the remediation effect of heavy metal pollution, organic fertilizers with different maturity levels were added to cadmium-contaminated soil. The remediation effect was determined by evaluating the form transformation and bioavailability of cadmium in heavy metal-contaminated soil. -Results showed that when the maturity was 50%, although the soil humus (HS) content increased, it didn't contribute to reducing the bioavailability of soil Cd. Appropriately increasing the maturity (GI ≥ 80%), the HS increased by 113.95%∼157.96%, and reduced significantly the bioavailability of soil Cd, among the exchangeable Cd decreased by 16.04%∼33.51% (P < 0.01). The structural equation modeling (SEM) revealed that HS content is a critical factor influencing the transformation of Cd forms and the reduction of exchangeable Cd accumulation; the HS and residual Cd content were positively correlated with the maturity (P < 0.01), while exchangeable Cd content was negatively correlated with maturity (P < 0.01), and the correlation increased with increasing maturity. In summary, appropriately increasing the maturity (GI ≥ 80%) can increase significantly HS, promote the transformation of exchangeable Cd into residual Cd, and ultimately enhance the effectiveness of organic fertilizers in the remediation of soil Cd pollution. These results provide a new insight into the remediation of Cd-contaminated soil through organic fertilizer as soil amendment in Cd-contaminated soil.

Primary cutaneous anaplastic large-cell lymphoma resembling infratemporal space infection: a case report.

BACKGROUND: Primary cutaneous anaplastic large-cell lymphoma (PC-ALCL) is a rare T-cell lymphoma belonging to the CD30 + T-cell lymphoproliferative disorders. The case of PC-ALCL in the temporal region is exceedingly rare. Herein, we report a case of PC-ALCL involving the temporal region mimicking infratemporal space infection. CASE PRESENTATION: A 78-year-old woman presented to maxillofacial surgery service with a 6-month history of swelling and pain in the left side of her face. Laboratory investigations found an elevated C-reactive protein (CRP). Imaging findings showed enlarged lymph nodes and extensive thickening of subcutaneous tissue of the left temples. Based on these findings, the infratemporal space infection was suspected initially. The patient underwent incision and drainage, and we unexpectedly found no pus in the lesion area. Incisional biopsy showed necrosis and extensive involvement of the left temples by a diffuse infiltrate containing large, atypical cells. The tumor cells were positive for CD30, CD3, Ki67. They were negative for ALK (SP8), CD5, CD8, CD20 and PAX5. After considering these findings, a diagnosis of PC-ALCL was rendered. The patient was admitted to the lymphoma department for systemic chemotherapy and no relapse occurred during a follow-up period of six months. CONCLUSIONS: This report suggests that if there are suspicious intraoperative manifestations, carrying out a biopsy simultaneously, using Hematoxylin and eosin (HE) staining, and a comprehensive Immunohistochemistry (IHC) panel are essential to diagnosing PC-ALCL to prevent misdiagnosis.

Prognostic significance of CircRNAs expression in oral squamous cell carcinoma.

This systematic review was aimed to comprehensively evaluate the clinicopathological and prognostic value of dysregulated expression of circRNAs in OSCC. The research was carried out by searching mainstream electronic databases including PubMed, Embase, Web of Science, Scopus, LILACS, and Cochrane Library to collect relevant studies on prognostic role of circRNAs in OSCC. Pooled hazard ratios (HRs) and odds ratios (ORs) with 95% confidence intervals (CIs) were calculated to assess the association between circRNAs expression, overall survival (OS), disease/recurrence/progression survival (DFS/RFS/PFS), and clinical parameters. This research included 1813 patients from 26 selected articles. The pooled HR values (95% CIs) in OS were 2.38 (1.92-2.93) for oncogenic circRNAs and 0.43 (0.28-0.66) for tumor-suppressor circRNAs, respectively, in DFS/RFS/PFS were 2.34 (1.73-3.17). The meta-analysis on clinicopathology features showed higher level of oncogenic circRNAs is related to advanced TNM stage, tumor stage, worse histological differentiation, positive lymph node and distant metastasis, while enforced expression of tumor-suppressor circRNAs is related to inferior TNM stage, tumor stage and lymphatic metastasis. In conclusion, our meta-analysis implies that circRNAs may be candidate biomarkers for the prognosis and clinicopathology of OSCC.

Upregulation of mmu_circ_0001066 attenuates the inhibitory effect of bisphosphonates on osteoclastogenesis.

OBJECTIVE: Medication-related osteonecrosis of the jaw (MRONJ) is the main adverse side effect of bisphosphonates (BPs), mainly owing to the inhibitory effect of BPs on osteoclastogenesis. CircRNAs were identified to be an important factor in regulating cellular processes. The aim of this study was to explore the effect of mmu_circ_0001066 on BP-inhibited osteoclastogenesis. MATERIALS AND METHODS: The expression of MRONJ-related miRNA in RANKL-induced RAW264.7 cells treated with BP was analyzed using qRT-PCR analysis. Bioinformatics techniques were applied to screen potential circRNAs. Tartrate-resistant acid phosphatase (TRAP) staining and bone resorption assays were used to examine the effect of mmu_circ_0001066 on osteoclastogenesis. Bioinformatics analysis, luciferase reporter assays, and Western blotting assays were performed to investigate the underlying mechanism. RESULTS: Four MRONJ-related miRNAs were upregulated in BP-treated RAW264.7 cells, and the expression of mmu_circ_0001066 was negatively correlated with those of MRONJ-related miRNAs. Furthermore, the upregulation of mmu_circ_0001066 partially attenuated the inhibitory effect of BP on osteoclastogenesis in RAW264.7 cells. Mechanistically, upregulated miR-16 suppressed osteoclastogenesis and miR-16 inhibitor increased osteoclastogenesis. Furthermore, we have identified that miR-16 is a downstream effector of mmu_circ_0001066. CONCLUSION: Our results suggest that mmu_circ_0001066 played an important role in the BP-mediated suppression of osteoclastogenesis, which lays a foundation for identifying mmu_circ_0001066 as a potential biomarker for MRONJ.

Circ-LRP6 mediates epithelial-mesenchymal transition and autophagy in oral squamous cell carcinomas.

BACKGROUND: Tumor metastasis seriously affects the therapeutic effect and prognosis of cancer patients. Here, we studied the role of has_circ_0000378 (circ-LRP6) in oral squamous cell carcinoma (OSCC) metastasis to explore new ideas and schemes for clinical treatment. METHODS: The expressions of circ-LRP6 in OSCC and normal tissues from matched controls were measured by real-time PCR (RT-PCR). Levels of epithelial-mesenchymal transition (EMT) transcription factors, P62 and LC3B, were determined by Western blot analysis and immunofluorescence (IF) assay. Furthermore, we evaluated the effects of circ-LRP6 downregulation on migration, invasion, and autophagy using CCK8, transwell assays, transmission electron microscopy (TEM), and immunofluorescence (IF) assay. RESULTS: The expression of circ-LRP6 in OSCC tissues was high. Downregulation of circ-LRP6 reduced the EMT process of SCC-15 cells, as evidenced by increased E-cadherin and decreased vimentin and Zeb1 levels. Downregulation of circ-LRP6 also decreased autophagy as shown by increased levels of P62 and decreased LC3B in SCC-15 cells. Autophagy revulsant rapamycin (RAPA) rescued the inhibitory effect of circ-LRP6 on LC3B, vimentin, and Zeb1. CONCLUSIONS: circ-LRP6 promoted EMT and autophagy of OSCC and increased autophagy could rescue EMT in OSCC cells inhibited by circ-LRP6 siRNA.

CiRS-7 functions as a ceRNA of RAF-1/PIK3CD to promote metastatic progression of oral squamous cell carcinoma via MAPK/AKT signaling pathways.

PURPOSE: Recent findings have shown that circRNA dysregulation was involved in the development of many types of cancer. However, our knowledge of circRNA in oral squamous cell carcinoma (OSCC) remains elusive. METHODS: Here, we explored whether ciRS-7 could function as a ceRNA in promoting metastasis of OSCC via regulating miR-7 activity. The expression levels of ciRS-7 and miR-7 were examined in clinical samples and cell lines by qRT-PCR, and the effects of ectopic expression of ciRS-7 and miR-7 on cell proliferation, migration and invasion were assessed in vitro and in vivo. The effects of ciRS-7 on miR-7 activity were investigated by means of luciferase reporter assay, qRT-PCR and Western blot. In addition, the effects of miR-7 mediated ciRS-7 on the levels of MAPK/AKT signaling proteins were evaluated by Western blot. RESULTS: We found that ciRS-7 was highly expressed in OSCC tissues and cell lines compared with normal counterparts. Ectopic expression of ciRS-7 significantly promoted OSCC cell proliferation, migration and invasion through in vitro and in vivo. Based on bioinformatics analysis, qRT-PCR, Western blot and luciferase reporter assays, we determined that ciRS-7 functioned as a sponge for miR-7, resulting in attenuation of miR-7 targets RAF-1 and PIK3CD, which are core components of the MAPK/AKT signaling pathways. Moreover, miR-7 correlated with perineural and lymphovascular invasion in OSCC patients. Further experiments demonstrated that ciRS-7 overexpression could attenuate the anti-tumor effects of miR-7 on OSCC cells. CONCLUSIONS: Our results suggested that ciRS-7 can interact directly with miR-7, resulting in upregulation of RAF-1/PIK3CD expression and enhancing metastatic progression of OSCC.

Suppression of OSCC malignancy by oral glands derived-PIP identified by iTRAQ combined with 2D LC-MS/MS.

Oral squamous cell carcinoma (OSCC) is the most common malignancy in head and neck cancer and a global cause of cancer-related death. Due to the poor survival rates associated with OSCC, there is a growing need to develop novel technologies and predictive biomarkers to improve disease diagnosis. The identification of new cellular targets in OSCC tumors will benefit such developments. In this study, isobaric tags for relative and absolute quantitation (iTRAQ)-based proteomics analysis combined with 2-dimensional liquid chromatography and tandem mass spectrometry (2D LC-MS/MS) were used to identify differentially expressed proteins (DEPs) between tumor and normal tissues. Of the DEPs detected, the most significantly downregulated protein in OSCC tissue was prolactin-inducible protein (PIP). Clonogenic and 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) experiments showed that the proliferation capacity of OSCC cells overexpressing PIP decreased due to cell cycle arrest at the G0/G1 checkpoint. Wound-healing and transwell assay further showed that PIP overexpression also reduced the migration and invasion of OSCC cells. Immunohistochemistry (IHC) was used to analyze the expression in OSCC, indicating that PIP may be secreted by glandular cells and have an inhibitory effect on OSCC cells to produce. In western blot analysis, silencing studies confirmed that PIP mediates these effects through the AKT/mitogen-activated protein kinase (MAPK) signaling axis in OSCC cells. Taken together, this study reveals PIP as a key mediator of OSCC cell growth, migration, and invasion through its effect on AKT/MAPK signaling.

circ-PKD2 inhibits carcinogenesis via the miR-204-3p/APC2 axis in oral squamous cell carcinoma.

Recent findings have shown that dysregulation of circular RNAs (circRNAs) is implicated in various cancers. However, the contribution of circRNAs in oral squamous cell carcinoma (OSCC) remains largely unexplored. We screened circRNA expression profiles using a circRNA microarray in paired OSCC and normal tissues and explored the clinical significance of a downregulated circRNA, circ-PKD2. Moreover, the biological function of circ-PKD2 in OSCC was investigated both in vitro and in vivo. We found that downregulation of circ-PKD2 in OSCC correlated significantly with aggressive characteristics. Further analysis revealed that overexpression of circ-PKD2 inhibited OSCC cell proliferation, migration and invasion, induced apoptosis and cell cycle arrest, which were promoted by knockdown of circ-PKD2. In addition, circ-PKD2 was identified as a sponge for miR-204-3p and upregulated the expression of adenomatous polyposis coli 2 (APC2), which was the functional target of miR-204-3p. Moreover, circ-PKD2 attenuated the oncogenic effects of miR-204-3p-mediated APC2 on OSCC progression via multiple signaling pathways. These results demonstrate that the circ-PKD2/miR-204-3p/APC2 axis represents a novel pathway involved in the pathogenesis of OSCC and may serve as a novel therapeutic target of OSCC.

Decreased expression of hsa_circ_0072387 as a valuable predictor for oral squamous cell carcinoma.

OBJECTIVE: Increasing evidence points toward the key function of circular RNAs (circRNAs) in various carcinomas. This study aimed to identify aberrant expression of hsa_circ_0072387 in oral squamous cell carcinoma and probe its clinical significance. MATERIALS AND METHODS: Real-time quantitative reverse transcription-polymerase chain reaction (qRT-PCR) was used to assess hsa_circ_0072387 expression levels in 63 paired OSCC tissues and three OSCC cell lines. The area under the receiver operator characteristic (ROC) curve was plotted to assess any potential clinical significance. RESULTS: Our data showed that hsa_circ_0072387 expression in OSCC was significantly downregulated compared with adjacent normal tissues (p < 0.001). Compared to human normal oral keratinocyte cell, the levels of hsa_circ_0072387 were lower in three OSCC cell lines (SCC25, SCC15, CAL27). More significantly, hsa_circ_0072387 expression was associated with the TNM stage in OSCC (p = 0.050). The area under the ROC curve reached up to 0.746. Based on bioinformatics, hsa-miR-129-3p, hsa-miR-141-3p, and hsa-miR-29-3p were predicted to be potential miRNAs binding with hsa_circ_0072387. Furthermore, hsa-miR-129-3p, hsa-miR-141-3p, and hsa-miR-29-3p were involved in multiple tumor-related signaling pathways. CONCLUSION: Our finding suggested that lower expression of has_circ_0072387 could be a key circRNA in OSCC and serve as a potential biomarker in OSCC diagnosis and therapeutic targets.

PTENp1, a natural sponge of miR-21, mediates PTEN expression to inhibit the proliferation of oral squamous cell carcinoma.

PTENp1, non-coding RNA (ncRNA) pseudogene, is involved in oral squamous cell carcinoma (OSCC). The precise effects mediated by PTENp1 transcripts within intricate regulatory networks involving molecular interactions with ancestral gene PTEN and tumorigenicity in OSCC remain unclear. Here, we found that PTENp1 was aberrantly expressed in OSCC. There was a positive correlation between the expression levels of PTENp1 and PTEN. Further, we showed that PTENp1 acted as a competing endogenous RNA that protects PTEN transcripts from being inhibited by miR-21, and consequently inhibited proliferation and colony formation and triggered S-G2/M cell cycle arrest through the AKT pathway. Also, the homogeneous relationship between expression of PTENp1 and PTEN was confirmed in OSCC tumor xenografts. Finally, low expression of PTENp1 and PTEN was negatively associated with histological differentiation and OSCC prognosis. The present work provided the first evidence for the extraordinary crosstalk among PTENp1, PTEN, and miR-21, and rendered a new light on the treatment of OSCC. © 2016 Wiley Periodicals, Inc.

Circulating high mobility group AT-hook 2 and pleomorphic adenoma gene 1 in blood of patients with oral squamous cell carcinoma.

BACKGROUND: High mobility group AT-hook 2 (HMGA2) and pleomorphic adenoma gene 1(PLAG1) have been demonstrated to be elevated in many malignant tumors. However, the aim of this study was to evaluate HMGA2 and PLAG1 levels in blood as a non-invasive biomarker for oral squamous cell carcinoma (OSCC) diagnosis. METHODS: qRT-PCR was performed to measure circulating HMGA2 and PLAG1 levels in OSCC patients (n=43) and matched cancer-free blood control group (n=21). Clinical data of all patients were recorded. RESULTS: Circulating HMGA2 and PLAG1 in the 43 OSCC patients was significantly higher than in control group (P<.001, P=.038, respectively). Furthermore, HMGA2 expression in OSCC patients with poor-moderate differentiation was increased compared with well-differentiated group. However, no significant differences in PLAG1 expression were detected when differentiation was considered. In addition, the receiver operating characteristic (ROC) curve analysis for circulating HMGA2 revealed an area under the ROC curve of 0.876 (95% confidence interval, 0.793-0.959; P<.001) with 65.1% sensitivity and 100% specificity in discriminating OSCC from controls at a cutoff value of 14.380, demonstrating significant diagnostic value for OSCC. CONCLUSION: Circulating HMGA2 levels are increased in OSCC patients and may potentially serve as a significant index to evaluate OSCC diagnosis.

Low-dose propranolol for infantile hemangioma of the head and neck: Analysis of 23 consecutive patients.

BACKGROUND: More and more infantile hemangiomas (IH) are being treated with propranolol, but the effectiveness, dosage, and treatment course are still in dispute. The aim of this observational study was to describe the therapeutic response, tolerance, and safety of low-dose propranolol in 23 children with IH of the head and neck. METHODS: Data were collected from the medical charts of patients treated with low-dose propranolol from December 2009 through November 2011. Oral dose was 1-1.5 mg/kg once per day. Blood pressure and heart rate were monitored during the first 24 h of treatment. In the absence of side-effects, treatment was continued at home and the child was re-evaluated every month. RESULTS: All patients had a good response, even if treated with corticosteroid previously. Color and growth changes within 1 week were noted. Treatment continued for a mean total duration of 6 months until the IH had totally disappeared or stabilized. There were no severe adverse reactions. Side-effects were limited and mild, including blood pressure decrease, somnolence, and nausea. No relapse was noted. CONCLUSIONS: Low-dose propranolol appears to be effective and safe for IH, especially for those patients previously treated with corticosteroid and who had no response or severe side-effects.

Comparing Modified with Conventional Parotidectomy for Benign Parotid Tumors.

PURPOSE: We conducted a study to compare the functional outcomes and surgical complications of patients with benign parotid tumors treated with conventional parotidectomy and modified parotidectomy. METHODS: This study retrospectively analyzed 99 patients who had benign parotid lesions and underwent parotidectomy using either conventional or modified parotidectomy. The operation time, cosmetic outcome, great auricular nerve anesthesia, incidence of Frey syndrome, and secretory function with the two techniques were compared. RESULTS: The mean operation time was shorter and the total complication rate was obviously lower in the modified surgery group (p < 0.001). In the modified surgery group, the incision was more cosmetic (p < 0.001), the sensory deficit rate was low (p < 0.001), and the sensory recovery rate was high, and transient facial paralysis and Frey syndrome were rare. Furthermore, glandular function was preserved in patients with a conserved Stensen duct. There was no tumor recurrence in the two groups during a mean follow-up of 29.8 months. CONCLUSION: Modified surgical techniques for benign parotid neoplasms significantly reduced the surgery time and improved the surgery outcomes compared with the conventional approach. This adds to the evidence to support the effectiveness of modified parotidectomy in selected patients with benign parotid tumors.

[A Study of the Relationship Among Genetic Distances, NIR Spectra Distances, and NIR-Based Identification Model Performance of the Seeds of Maize Iinbred Lines].

This paper explored the relationship among genetic distances, NIR spectra distances and NIR-based identification model performance of the seeds of maize inbred lines. Using 3 groups (total 15 pairs) of maize inbred lines whose genetic distaches are different as experimental materials, we calculates the genetic distance between these seeds with SSR markers and uses Euclidean distance between distributed center points of maize NIR spectrum in the PCA space as the distances of NIR spectrum. BPR method is used to build identification model of inbred lines and the identification accuracy is used as a measure of model identification performance. The results showed that, the correlation of genetic distance and spectra distancesis 0.9868, and it has a correlation of 0.9110 with the identification accuracy, which is highly correlated. This means near-Infrared spectrum of seedscan reflect genetic relationship of maize inbred lines. The smaller the genetic distance, the smaller the distance of spectrum, the poorer ability of model to identify. In practical application, near infrared spectrum analysis technology has the potential to be used to analyze maize inbred genetic relations, contributing much to genetic breeding, identification of species, purity sorting and so on. What's more, when creating a NIR-based identification model, the impact of the maize inbred lines which have closer genetic relationship should be fully considered.

MiR-21 modulates chemosensitivity of tongue squamous cell carcinoma cells to cisplatin by targeting PDCD4.

Chemoresistance is a challenge for clinician in management of tongue cancer. Therefore, it is necessary to explore alternative therapeutic methods to overcome drug resistance. miRNAs are endogenous -22nt RNAs that play important regulatory roles by targeting mRNAs. miR-21, an essential oncogenic molecule, is associated with chemosensitivity of several human cancer cells to anticancer agents. In this study, we investigated the effects and molecular mechanisms of miR-21 in chemosensitivity of tongue squamous cell carcinoma cells (TSCC) to cisplatin. miR-21 expression was detected in tongue cancer tissue using RT-PCR and PDCD4 protein expression was measured using immunohistochemistry. miR-21 and(or) PDCD4 depleted cell lines were generated using miR-21 inhibitor and(or) siRNA. The viabilities of treated cells were analyzed using MTT assay. RT-PCR was used to detect miR-21 expression and immunoblotting was used to detect protein levels. Cell cycle and apoptosis were analyzed using propidium iodide (PI) staining and Annexin V/PI staining, respectively. The expression of miR-21 in tumorous tissue was significantly higher compared with adjacent normal tissue and loss of PDCD4 expression was observed in TSCCs. Transfection of miR-21 inhibitor induced sensitivity of TSCC cells (Tca8113 and CAL-27) to cisplatin. TSCC cells transfected with PDCD4 siRNA became more resistant to cisplatin therapy. We found an increase PDCD4 protein level following the transfection of miR-21 inhibitor using Western blot analysis. In addition, the enhanced growth-inhibitory effect by miR-21 inhibitor was weakened after the addition of PDCD4 siRNA. Suppression of miR-21 or PDCD4 could significantly promote or reduce cisplatin-induced apoptosis, respectively. Our data suggest that miR-21 could modulate chemosensitivity of TSCC cells to cisplatin by targeting PDCD4, and miR-21 may serve as a potential target for TSCC therapy.

Circulating microRNA-21 (MIR-21) and phosphatase and tensin homolog (PTEN) are promising novel biomarkers for detection of oral squamous cell carcinoma.

The purpose of this study was to investigate the potential of the blood levels of MIR-21 and PTEN as novel biomarkers for oral squamous cell carcinoma (OSCC). We initially detected MIR-21 and PTEN using real-time RT-PCR from 90 blood samples and then compared their results with expression in cancer tissues from 10 OSCC patients. Finally, we examined the relationship between these markers and clinical parameters. Blood MIR-21 and PTEN had significant diagnostic value for OSCC and, to an extent, correlated with the expression level of tumour MIR-21 and PTEN. In addition, they were associated with differentiation and nodal status. Thus circulating MIR-21 and PTEN might represent new complementary tumour markers for OSCC.