An improved sample container cup and its effect on NIRS of tobacco smoke for quality stability estimation.

This paper describes a design of an improved self-made Bruker NIR cup and analyzes the effect of the equipment modification to fit the Cambridge filter pad, which enhances experimental efficiency and reduces operational complexity. A self-made NIR cup based on the classical NIR cup is designed to speed up the operation process and reduce the experiment's time cost. To estimate the effect of this equipment modification, the NIR spectra from the classical sample cup and the new self-made cup are compared and analyzed. Furthermore, the quality evaluation results from NIR data of the two cups are also compared according to a distance metric chemometrics method, which shows quality analytical values between these two cups are approaching each other while the experiment efficiency is improved.•This paper introduces a newdesign of a self-made container cup improved from the Bruker's traditional sample container cup to better fit the filter pad and improve the experiment efficiency and convenience.•This paper also analyzes the effect of this container cup change by comparing the NIR spectra before and after modification.

Clinical relevance of serum lipids in the carcinogenesis of oral squamous cell carcinoma.

BACKGROUND: Dyslipidaemia is associated with cancers. However, the specific expression of serum lipids in oral potentially malignant disorders (OPMD) and oral squamous cell carcinoma (OSCC) remains unclear, and it remains unknown whether serum lipids are associated with the development of OPMD and OSCC. This study investigated the serum lipid profiles of OPMD and OSCC patients, and the association of serum lipids with the occurrence of OPMD and OSCC. METHODS: A total of 532 patients were recruited from the Affiliated Hospital of Stomatology, Nanjing Medical University. Serum lipid parameters including total cholesterol (TC), triglycerides (TGs), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), apolipoprotein A (Apo-A), apolipoprotein B (Apo-B), and lipoprotein (a) (Lpa) were analysed, and clinicopathological data were collected for further analysis. Furthermore, a regression model was used to evaluate the relationship between serum lipids and the occurrence of OSCC and OPMD. RESULTS: After adjusting for age and sex, no significant differences were observed in serum lipid or body mass index (BMI) between OSCC patients and controls (P > 0.05). HDL-C, Apo-A, and Apo-B levels were lower in OSCC patients than in OPMD patients (P < 0.05); HDL-C and Apo-A levels were higher in OPMD patients than in controls (P < 0.05). Furthermore, female OSCC patients had higher Apo-A and BMI values than males. The HDL-C level was lower in patients under 60 years of age than in elders (P < 0.05); and age was related to a higher risk of developing OSCC. Female patients with OPMD had higher TC, HDL-C, and Apo-A levels than males (P < 0.05); OPMD patients over 60 years of age had higher HDL-C than youngers (P < 0.05), whereas the LDL-C level was lower in elders (P < 0.05). The HDL-C and BMI values of the patients with oral leukoplakia (OLK) with dysplasia were more elevated than those of the oral lichen planus group, and the LDL-C, and Apo-A levels in patients with OLK with dysplasia were decreased (P < 0.05). Sex, high HDL-C and Apo-A values were associated with the development of OPMD. CONCLUSION: Serum lipids exhibited certain differences according to the occurrence and development of OSCC; high levels of HDL-C and Apo-A might be markers for predicting OPMD.

Nutlin-3 suppresses tumorigenesis and progression of oral squamous cell carcinoma and enhances chemosensitivity to cisplatin.

Oral squamous cell carcinoma (OSCC) is an epithelial malignant tumor with great challenges of tumor metastasis and drug resistance. Nutlin-3 is a MDM2 inhibitor that can potently activate tumor suppressor gene p53. However, the exact role of Nutlin-3 in OSCC has not been identified yet. SCC-9 cells were treated with 0, 2.5, 5, 10, 20 µM Nutlin3. MDM2 and p53 protein levels were assessed using western blot analysis. Then, CCK8 assay, clone formation assay, TUNEL staining, wound healing and transwell assays were conducted to analyze the influences of Nutlin3 on the proliferation, apoptosis, migration, and invasion in SCC-9 cells. Moreover, SCC-9 cells were co-treated with 0, 0.5, 1, 2.5, 5 µM cisplatin and Nutlin3 to determine the effect of Nutlin3 on cisplatin chemosensitivity in OSCC. As expected, Nutlin-3 inhibited MDM2 but restored p53 in OSCC in a concentration-dependent manner. Meanwhile, Nutlin-3 suppressed the proliferation, clone formation, migration, invasion and epithelial-mesenchymal transition of SCC-9 cells and both boosted the apoptosis. In addition, Nutlin-3 caused a reduced cell viability and an elevated cell apoptosis rate in cisplatin-treated SCC-9 cells, indicating that Nutlin-3 enhanced cisplatin chemosensitivity in OSCC cells. Taken together, Nutlin-3 may suppress tumorigenesis and progression of OSCC and enhance chemosensitivity to cisplatin in OSCC.

Catalase-integrated metal-organic framework with synergetic catalytic activity for colorimetric sensing.

As a platform for enzyme immobilization, metal-organic frameworks (MOFs) can protect enzyme activity from the interference of external adverse environment. Although these strategies have been proven to produce good results, little consideration has been given to the functional similarity of MOFs to the encapsulated enzyme. Here, catalase (CAT) was encapsulated in Fe-BTC with peroxidase-like activity to obtain a stable composite (CAT@Fe-BTC) with synergistic catalytic activity. Depending on the superior selectivity and high catalytic activity of CAT@Fe-BTC, colorimetric sensing for the detection of hydrogen peroxide and phenol was developed. This work demonstrates that the integration of functional MOFs with natural enzyme can be well applied to the construction of efficient catalysts.

[Application of 3D printing technology under three-dimensional reconstruction in mandibular reconstruction].

PURPOSE: To explore the application value of 3D printing technology under three-dimensional reconstruction in mandibular reconstruction. METHODS: Eighty-four patients with mandibular defect reconstruction were divided into two groups by different operation methods: 3D group(n=42) and control group(n=42). Patients in the control group underwent routine operation, while patients in the experimental(3D) group underwent three-dimensional reconstruction with 3D printing technology. The operation conditions, incidence of complications, recovery of facial features and occlusal relationship were recorded. SPSS 23.0 software package was used for statistical analysis of the data. RESULTS: The operation time of 3D group was significantly shorter than that of the control group, and the amount of bleeding was significantly less than that of the control group(P<0.05). The recovery rate of facial appearance and occlusal relationship in 3D group was significantly higher than in the control group(95.24% vs 78.57%, P<0.05). Compared with the control group, the movement distance of mandibular points in 3D group was significantly smaller before and after operation(P<0.05). The satisfaction scores of chewing function and pronunciation recovery in the two groups were close(P>0.05), but compared with the control group, the satisfaction scores of appearance recovery in the 3D group were significantly higher(P<0.05). CONCLUSIONS: 3D reconstruction under 3D printing technology can reduce intraoperative bleeding, shorten the operation duration, and achieve good shape recovery with high degree of satisfaction.

Evaluation of autofluorescence visualization system in the delineation of oral squamous cell carcinoma surgical margins.

INTRODUCTION: Delineating the margins of Oral squamous cell carcinoma (OSCC) is a critical step for optimaltumor resection. The aim of this study was to evaluate the accuracy of lesion surgical margin identification using autofluorescence visualization. MATERIALS AND METHODS: Thirty patients with OSCC were included in this study. For each lesion, the fluorescence loss boundary was determined using VELscope before ablative surgical resection (with a 1.5-2cm safety margin) was performed. A total of 126 samples were obtained from 30 surgical specimens, each containing the tissue from the fluorescence loss boundary to surgical margin. The status of each sample was determined by oral pathologists and the staining intensities of Ki-67, E-cadherin, and Vimentin at the fluorescence loss boundary and surgical margin were evaluated by immunohistochemistry. RESULTS: Fluorescence loss regions were identified in all patients. Of the 126 samples collected, HE staining identified 77 normal epithelia (61.1%), 26 mild dysplasia (20.6%), 17 severe dysplasia (13.4%) and 6 carcinomas in situ (4.9%). A significant correlation was found between the differentiation grade of tumor cells and the pathological status of the surgical marginal specimens (P<0.05). Forty-two of the 126 samples were randomly selected for further immunohistochemical staining. No significant differences were seen in Ki-67, E-cadherin, or Vimentin expression at the fluorescence loss boundary or surgical margin, however, the proteins' expression level was positively correlated with the degree of dysplasia (P<0.01). CONCLUSION: Autofluorescence visualization has potential as a simple surgical margin setting device for OSCC and may help delineate the superficial area of OSCC with acceptable accuracy. However, when considering the inherent limitations of this system, we suggest that the approach should only be applied under certain conditions, such as when dealing with superficial, well-differentiated lesions.

Analgesic efficacy of imrecoxib for postoperative pain following oral surgery: a prospective randomized, active-controlled, non-inferiority trial.

BACKGROUND: Imrecoxib, a novel cyclooxygenase (COX-2) selective non-steroidal anti-inflammatory drug (NSAID), has been approved in China for more than 9 years. This study aimed to assess the efficacy and safety of imrecoxib compared with celecoxib for patients with moderate or severe acute pain following oral surgery. METHODS: Patients with moderate or severe pain within 6 hours following surgery were enrolled in this randomized, active-control trial. Patients were randomly assigned (1:1) to receive either imrecoxib or celecoxib. Pain assessments on the visual analog scale, verbal rating scale, and pain relief were conducted at 0.5, 1, 2, 4, 6, 9, 12, and 24 hours after the first dose. Adverse events were also recorded. RESULTS: Eighty-seven patients were approached from November 2018 to August 2019. Of these, 60 were eligible for randomization. Ultimately, 56 patients (imrecoxib group, n=27; celecoxib group, n=29) were included in the analysis. The difference in total pain relief (TOTPAR) between the imrecoxib and celecoxib groups was 1.03 [95% confidence interval (CI): -1.31-3.77], with the lower bound of the CI above the specified non-inferiority boundary. No perioperative complications were observed in the imrecoxib group during the 24-hour period after the first dose. CONCLUSIONS: Imrecoxib could significantly relieve pain and has a non-inferior analgesic efficacy compared to celecoxib with good tolerance following oral surgery.

SATB2 overexpression promotes oral squamous cell carcinoma progression by up-regulating NOX4.

While atypical expression of special AT-rich sequence-binding protein 2 (SATB2) has been approved associated with tumor progression, metastasis and unfavourable prognosis in various carcinomas. However, in oral squamous cell carcinoma (OSCC), both the expressive state and associated functions of SATB2's are still undefined. Here we show that, in clinical samples from a retrospective cohort of 58 OSCC patients, high expression of SATB2 is associated with poor prognosis of OSCC patients. In this study, we investigated SATB2 is highly expressed in OSCC tissues and cell lines, which can promote OSCC cells' proliferation, migration, invasion and tumor growth. According to sequencing results based on previous literature, we identified NOX4 is a bona fide downstream target of SATB2, when it was knockdown, OSCC's proliferation can be partially suppressed. Furthermore, NOX4 knockdown inhibits tumorigenicity, which can be rescued partially by ectopic expression of SATB2 in HNSCC cell line, and vice versa. Collectively, our findings not only indicate overexpression of SATB2 triggers the proliferative, migratory and invasive mechanisms which are important in the malignant phenotype of OSCC, but also identify NOX4 as the downstream gene for SATB2. These findings indicate that SATB2 may play a key role in OSCC tumorigenicity and may be a future target for the development of new therapeutic regimens.

Mahalanobis distance based similarity regression learning of NIRS for quality assurance of tobacco product with different variable selection methods.

Quality assurance is one of the key issues in tobacco industry and many efforts have been put on the quality control. This paper introduces a new chemometrics technique to estimate the "quality similarity rate", which is used for quality control. The value of the quality similarity rate represents the similarity degree between the products and the standard reference samples, which is a global parameter that can be generated by either human assessors or machine learning. Supervised similarity regression models are built to automatically estimate the quality similarity rate value from NIRS data of tobacco leaf and smoke. For the similarity regression learning, the metric matrix is generated by a novel method which calculates the Mahalanobis distance from the segmented near infrared spectroscopy (NIRS). The results show the similarity regression learning can predict the quality similarity score well in high speed and can be improved with lasso (least absolute shrinkage and selection operator) related feature selection algorithms such as sRDA (sparse redundancy analysis) and glmnet.

[Effect of mi-138 targeting PLD2 gene on proliferation and migration of oral cancer cells].

PURPOSE: To investigate the effect of miR-138 targeting PLD2 gene on proliferation and migration of oral cancer cells. METHODS: After oral cancer cells were transfected with miR-138, the expression level of microRNA-138 was detected by RT-PCR assay, the proliferation ability was detected by MTT assay, and cell cycle distribution was detected by flow cytometry. Transwell migration assay was used to detect cell migration ability, Western blotting assay was used to detect the expression levels of MMP-9, PLD2 and cyclin D1 in gastric cancer cells. Luciferase assay was used to report the targeting relationship between microRNA-138 and PLD2 gene. SPSS 21.0 software package was used to analyze the data. RESULTS: After miR-138 was transfected into oral cancer cells, the relative expression level of miR-138 was 4.28±0.16, which was significantly higher than that of blank control and miR-NC group (P<0.05). Luciferase reporter gene assay showed that the relative activity of PLD2 wild plasmid luciferase was significantly lower in oral cancer cells transfected with microRNA-138 than in other groups (P<0.05); The expression level of PLD2 gene in miR-138 group was significantly lower than that in blank control group and miR-NC group (P<0.05). After oral cancer cells were transfected with miR-138, the proliferation ability of oral cancer cells in miR-373 group was significantly lower than that in control group and miR-NC group (P<0.05). Flow cytometry showed that the ratio of G0/G1 phase was (64.39±6.49)% in the group of miR-138, which was significantly higher than that in the blank control group and the group of miR-NC(P<0.05); The ratio of S phase in the group of miR-138 was(13.28±3.16)%, which was significantly lower than that in the blank control group and the group of miR-NC (P<0.05); There was no significant difference in the ratio of G2/M phase among the groups (P>0.05). Transwell experiment showed that the number of migrating cells transfected with miR-138 in oral cancer cells was 138.46±24.37, which was significantly lower than that in blank control group and miR-NC group(P<0.05). Western blotting experiments showed that the relative levels of MMP-9, vimentin and cyclin D1 in the miR-138 group were 0.14±0.04, 0.17±0.02 and 0.15±0.03, respectively, which were significantly lower than those in the blank control group and the miR-NC group(P<0.05). CONCLUSIONS: miR-138 can target PLD2 gene expression and inhibit the proliferation and migration of oral cancer cells.

Long Noncoding RNA LINC00460 Promotes Cell Progression by Sponging miR-4443 in Head and Neck Squamous Cell Carcinoma.

Head and neck squamous cell carcinoma (HNSCC) is one of the most common cancers worldwide. Long noncoding RNAs were proved to be associated with the development and progression in HNSCC. However, the mechanism of LINC00460 in HNSCC needs to be further investigated. The study used quantitative real-time polymerase chain reaction assay to detect the expression of LINC00460 in cancer tissues and cell lines. Gain and loss of function experiments were conducted to analyze the effects of LINC00460 and miR-4443 on cell proliferation, invasion, and apoptosis of HNSCC cells in vitro. The interactions among miR-4443 and LINC00460 were detected by dual-luciferase reporter assay. Here, the study showed that LINC00460 was highly expressed in HNSCC tissues and cell lines. Functionally, knockdown of LINC00460 inhibited HNSCC cell proliferation and migration in vitro. Besides, LINC00460 promoted cell progression by sponging miR-4443, and miR-4443 inhibitor could reverse the effects of si-LINC00460 on cell proliferation and migration. In summary, LINC00460 could potentially promote cell progression and epithelial mesenchymal transition by sponging miR-4443 in HNSCC. LINC00460 could be used as a potential therapeutic target for HNSCCs.

MiR-34a inhibits the proliferation, migration, and invasion of oral squamous cell carcinoma by directly targeting SATB2.

In various kinds of carcinomas, the special AT-rich sequence-binding protein 2 (SATB2) with its atypical expression promotes the metastasis and progression of the tumor, though in the oral squamous cell carcinoma (OSCC) its inherent mechanism and the status of SATB2 remain unclear. The role played by the SATB2 expression in the OSCC cell lines and tissue samples in the target of miR-34a downstream is the intended endeavor of this study. In te OSCCs the miR-34a expression was determined by quantitative real-time polymerase chain reaction (q-PCR), while the SATB2 expression in the cell lines and tissue samples in OSCC was analyzed with the q-PCR and the western blot. Studies in both in vitro and in vivo of the effects of miR-34a on the initiation of OSCC were conducted. As a direct target of the miR-34a the SATB2 was verified with the luciferase reporter assay. In cases where the miR-34a levels were low, the SATB2 in OSCCs seemed to be overexpressed. Besides, both in the in vitro and in vivo a suppression of migration, invasion, and cell growth was caused by miR-34a by down regulating the SATB2 expression. The SATB2 being a direct target of miR-34a was confirmed by the cotransfection of miR-34a mimics specifically the decrease in the expression of luciferase of SATB2-3'UTR-wt reporter. As a whole, our study confirmed the inhibition of miR-34a in the invasion, proliferation, and migration of the OSCCs, playing a potential tumor suppressor role with SATB2 as its downstream target.

Anatomical study and clinical application of medial sural artery perforator flap for oral cavity reconstruction.

The present study aims to provide anatomical evidence for clinical application of the medial sural artery perforator (MSAP) flap. The current study investigated the vascular anatomy of the flap, evaluated the postoperative appearance and function of the donor and recipient sites, and investigate the clinical value in reconstruction of oral cavity. Six lower limbs of Chinese adult cadavers were microsurgically dissected. The locations and courses of the medial sural artery perforators were identified and recorded, which provided an anatomical basis for clinical application. Then, 16 clinical cases employing this flap were evaluated, ranging from 3×4cm to 6×8cm, and were employed for defects in the oral cavity region. Sixteen clinical cases with intraoral soft tissue defects, which included four clinical cases with inner cheek defects, were successfully followed up for 10-47 months (24 months on average). The donor site function, contour of recipient site and oral function recovery were evaluated as acceptable or better in cases with intraoral soft tissue defect, which were further verifying the value of clinical application of MSAP in repairing oral cavity defects. Moreover, two typical clinical cases were described in detail. To conclude, the MSAP flap is a favorable choice for small- to medium-size defects based on minor donor site morbidity, satisfactory oral function recovery, perforator stability and adaptation of the pedicle for anastomosis in the oral cavity region.

FOXM1 is a novel predictor of recurrence in patients with oral squamous cell carcinoma associated with an increase in epithelial­mesenchymal transition.

Although forkhead box protein M1 (FOXM1) is markedly upregulated in human premalignant and oral squamous cell carcinoma (OSCC) tissues and cultured cells, the association of FOXM1 expression with OSCC prognosis is not well understood. The present study investigated the possible association of FOXM1 expression in patients with OSCC with their clinicopathological characteristics and clinical outcomes. The expression of FOXM1 protein in OSCC tissues from 119 patients was evaluated by immunohistochemistry, and the results demonstrated that FOXM1 overexpression in patients with OSCC was associated with tumour recurrence and poor prognosis. To study the in vitro effects of FOXM1, its expression was decreased by small interfering RNA (siRNA) in OSCC cell lines, and FOXM1 knockdown decreased the proliferative, migratory and invasive capacities of cells. FOXM1 inhibition by siRNA gave rise to reduced expression of vimentin and increased expression of E­cadherin. The present study reported FOXM1 as a novel predictor of tumour recurrence in patients with OSCC and its potential involvement in epithelial­mesenchymal transition in OSCC cells.

Discovery and preclinical validation of proteomic biomarkers in saliva for early detection of oral squamous cell carcinomas.

OBJECTIVES: Our aim was to identify and prevalidate a set of salivary proteins that can distinguish oral squamous cell carcinomas (OSCC) patients from healthy individuals and patients with oral potentially malignant disorders (OPMD). SUBJECTS AND METHODS: Proteomes of 60 saliva samples from healthy individuals, OPMD patients, and OSCC patients were assayed using the isobaric tags for relative and absolute quantitation (iTRAQ) method. Enzyme-linked immunosorbent assay (ELISA) was used to prevalidate the candidate biomarkers in an independent sample set (n = 90). RESULTS: In total, 246 differentially expressed proteins were identified by comparing each two groups, and 21 proteins were differentially expressed when OSCC was compared with both OPMD and Control. Three proteins, namely, solute carrier family 3 member 2 (SLC3A2), S100 calcium-binding protein A2 (S100A2), and interleukin-1 receptor antagonist protein (IL1RN), were selected as candidate biomarkers. Comparing the OSCC group with the healthy group, the area under curve (AUC) of the three combined biomarkers was 0.89, with a sensitivity of 83.33% and a specificity of 83.33%. Comparing the OSCC group with the OPMD group, the AUC value was 0.87, with a sensitivity of 93.33% and a specificity of 70.00%. CONCLUSION: Our study indicates that salivary proteomics is promising for the discovery of OSCC biomarkers.

High expression of TROP2 is correlated with poor prognosis of oral squamous cell carcinoma.

Human trophoblastic cell-surface antigen 2 (TROP2) is a cell surface glycoprotein that exhibits high expression in various carcinomas but low or no expression in normal tissues. High TROP2 expression plays an important role in promoting tumor development and aggressiveness, which is correlated with reduced patient survival. However, there are few studies regarding TROP2 in relation to both oral squamous cell carcinoma (OSCC) and oral potentially malignant lesions. The expression of TROP2 protein and mRNA was investigated in OSCC tissues, oral potentially malignant lesion tissues, and normal oral tissues using immunohistochemistry and quantitative real-time polymerase chain reaction (qRT-PCR). The association between TROP2 expression and clinicopathological characteristics of OSCC was also analyzed, and the prognostic value of TROP2 was evaluated. The expression of TROP2 protein and mRNA were both higher in OSCC tissues than in oral potentially malignant lesion tissues or normal oral tissues. Positive TROP2 expression was related to differentiation, lymph node metastases, TNM stage, perineural infiltration, and vascular invasion. Poor overall survival was associated with high TROP2 expression and other factors associated with poor overall survival including poor differentiation, lymph node metastasis, TNM stage, vascular invasion, and perineural invasion in univariate analyses. TROP2 expression as well as TNM stage and vascular invasion were independent prognostic factors associated with the overall survival of OSCC patients in multivariate analyses. In summary, High TROP2 expression is associated with poor overall survival and serves as an independent prognostic factor in OSCC. The results suggest that TROP2 expression could be an effective prognostic biomarker for OSCC.

[Expression and correlation of HPV16E6 and tumor suppressor gene p53 in oral squamous cell carcinoma].

PURPOSE: To exploring the expression of PV16E6 gene and p53 gene in patients with oral carcinoma and the correlation between pathological grade and clinical stage of oral cancer and expression of HPV16E6 gene and p53 gene. METHODS: One hundred and seventy-three cases of oral cancer, 98 cases of oral precancerous lesions and 79 cases of peri-cancerous normal tissue were selected. The expression of HPV16E6 and p53 was detected by immunohistochemistry. The data were analyzed using SPSS 21.0 software package. RESULTS: In oral carcinoma, the expression rate of HPV16E6 was 81.5% (141/173), the expression rate of p53 was 23.7% (41/173); in oral precancerous lesions, the expression rate of HPV16E6 was 39.8% (39/98), the expression rate of p53 was 57.1% (56/98); in peri-cancerous normal tissues, the expression rate of HPV16E6 was 2.5%(2/79), the positive expression rate of p53 was 89.9%(71/79). There was significant difference in the positive expression rate of p53 and HPV16E6 among 3 groups. The expression of HPV16E6 in oral cancer was significantly higher than in the other two groups(P<0.05); the expression rate of p53 in oral cancer was significantly lower than the other two groups. In addition, with the advance of clinical stage and pathological grade, the positive expression rate of HPV16E6 increased gradually, while the positive expression rate of p53 was significantly decreased (P<0.05). CONCLUSIONS: HPV16E6 protein and p53 protein may play an important role in the occurrence and progress of oral cancer.

Determination of nicotine in tobacco products based on mussel-inspired reduced graphene oxide-supported gold nanoparticles.

Polydopamine functionalized reduced graphene oxide-gold nanoparticle (PDA-RGO/Au) nanocomposites were successfully prepared by a simple and mild procedure. The PDA-RGO/Au nanocomposite is successfully formed in an aqueous buffer solution (pH 8.5) without using any reducing agent. FTIR confirmed the successful coating of PDA and informed the reduction of the surface functional groups of GO. The formation of reduced GO and Au NPs was further evidenced by UV-Vis and X-ray diffraction spectroscopy. This method is environmentally friendly and highly beneficial for the mass production of graphene-noble metal based nanocomposite. The as prepared PDA-RGO/Au nanocomposite could greatly enhance the electrochemical oxidation of nicotine. We fabricated an electrochemical nicotine sensor based on the prepared PDA-RGO/Au nanocomposite. The proposed nicotine sensor showed a wide detection range from 0.05 to 500 µM with a low detection limit of 0.015 µM. Moreover, the proposed nicotine sensor was also successfully applied for determination nicotine content in tobacco products.

Lactate dehydrogenase B is associated with the response to neoadjuvant chemotherapy in oral squamous cell carcinoma.

Oral squamous cell carcinoma (OSCC) comprises a subset of head and neck squamous cell carcinoma (HNSCC) with poor therapeutic outcomes and high glycolytic dependency. Neoadjuvant chemotherapy regimens of docetaxel, cisplatin and 5-fluorouracil (TPF) are currently accepted as standard regimens for HNSCC patients with a high risk of distant metastatic spread. However, the antitumor outcomes of TPF neoadjuvant chemotherapy in HNSCC remain controversial. This study investigated the role of lactate dehydrogenase B (LDHB), a key glycolytic enzyme catalyzing the inter-conversion between pyruvate and lactate, in determining chemotherapy response and prognosis in OSCC patients. We discovered that a high protein level of LDHB in OSCC patients was associated with a poor response to TPF regimen chemotherapy as well as poor overall survival and disease-free survival. Our in-depth study revealed that high LDHB expression conferred resistance to taxol but not 5-fluorouracil or cisplatin. LDHB deletion sensitized OSCC cell lines to taxol, whereas the introduction of LDHB decreased sensitivity to taxol treatment. Taxol induced a pronounced impact on LDHB-down-regulated OSCC cells in terms of apoptosis, G2/M phase cell cycle arrest and energy metabolism. In conclusion, our study highlighted the critical role of LDHB in OSCC and proposed that LDHB could be used as a biomarker for the stratification of patients for TPF neoadjuvant chemotherapy and the determination of prognosis in OSCC patients.

Monocarboxylate transporter 4 facilitates cell proliferation and migration and is associated with poor prognosis in oral squamous cell carcinoma patients.

Monocarboxylate transporter 4 (MCT4) is a cell membrane transporter of lactate. Recent studies have shown that MCT4 is over-expressed in various cancers; however, its role in cancer maintenance and aggressiveness has not been fully demonstrated. This study investigated the role of MCT4 in oral squamous cell carcinoma (OSCC), and found that it is highly expressed in OSCC patients by using immunohistochemistry. Moreover, this over-expression of MCT4 was closely associated with tumor size, TNM classification, lymphatic metastasis, distant metastasis and tumor recurrence, and also poor prognosis. To further study mechanisms of MCT4 in vitro, we used small-interfering RNA to silence its expression in OSCC cell lines. The results showed that knock-down of MCT4 decreased cell proliferation, migration, and invasion. The inhibition of proliferation was associated with down-regulation of p-AKT and p-ERK1/2, while decreased cell migration and invasion may be caused by down-regulation of integrin ß4-SRC-FAK and MEK-ERK signaling. Together, these findings provide new insight into the critical role of MCT4 in cell proliferation and metastasis in OSCC.