High expression of CD9 and Epidermal Growth Factor Receptor promotes the development of tongue cancer.

Tongue cancer is distinguished by aggressive behavior, a high risk of recurrence, lymph, and distant metastases. Hypoxia-Induced Factor 1 α functions as a CD9 transcription factor. CD9 is a transmembrane protein that may be found on the cell membrane. It can modulate the expression of the Epidermal Growth Factor Receptor (EGFR) pathway. ELISA was used to measure serum CD9, p-EGFR, and p-Akt levels in 70 tongue cancer patients and 35 healthy controls. RT-PCR was used to analyze the gene expression of the related genes. The gene as well as protein expression of CD9, EGFR/p-EGFR, and Akt/p-Akt was significantly higher in case subjects when compared with the controls. The expression of CD9 was higher in case subjects who were smokers/alcoholics when to control subjects who were smokers/alcoholics. Overexpression of CD9 due to hypoxic conditions leads to the activation of EGFR-signaling pathway resulting in cancer progression, resistance to chemotherapy. Hence, CD9 could be a potential target to suppress cancer progression.

Prognostic significance of tetraspanin CD9 and oncogenic epidermal growth factor receptor in tongue squamous cell carcinoma survival.

The most prevalent locations for head and neck cancer is the tongue. The surviving patients who are receiving therapy have considerably compromised speech, taste, chewing, and swallowing. CD9 is a cell surface protein that has contradictory role in cancer progression. The objective of the study is to analyze the Cluster of Differentiation 9(CD9), Epidermal Growth Factor Receptor (EGFR) and Phosphorylated Akt (p-Akt) expression in tongue cancer specimens and its clinical significance.50 tongue cancer sections were used to analyze the expression of CD9,EGFR and p-Akt by immunohistochemistry. Data regarding the histological grade of the tumor, age, sex, and habits were recorded, and relation with CD9,EGFR and p-Akt expression was assessed. Data were expressed as mean ± SEM. Categorical data was analyzed by Chi-square test. Student t-test was used to check the significance of data between two groups.A significant increase in the CD9,EGFR and p-Akt expression (1.8 ± 0.11, 2.06 ± 0.18 and 2.3 ± 0.15 respectively) was seen in the tongue cancer specimens. CD9 and p-Akt expression had a significant association with the histological grade (p < 0.004 and p < 0.006 respectively). CD9 expression was higher in patients with the combination of addiction/habit compared to patients with single addictions(1.08 ± 0.11 and 0.75 ± 0.47). Overall a poor rate of survival was observed in CD9 positive patients(p < 0.039). EGFR and p-Akt expression increased with increasing expression of CD9, suggesting its use as a biomarker to track the development of TSCC.

Tetraspanin CD9: A friend or foe of head and neck cancer (Review).

Head and neck cancers are diverse and complex diseases characterised by unregulated growth of tumour cells in various parts of the head and neck region, such as in the buccal mucosa, floor of the mouth, tongue, oropharynx, hypopharynx, oesophagus, nasopharynx and salivary glands. Partial or total glossectomy, radiation or chemotherapy greatly affect patient quality of life. However, even following treatment, patients may relapse. Nicotine­derived nitrosamines and alcohol are the major etiological factors underlying this deadly disease. These compounds induce DNA damage that may lead to mutation in crucial genes, such as p53 and p21, which are important to regulate cell proliferation, thus leading to cancer. CD9 is a tetraspanin, which are a group of transmembrane proteins that have a role in cell motility and adhesion. The present review aimed to explore the role of CD9 in head and neck cancer. Epidermal growth factor receptor activity and cell proliferation are regulated by the CD9­integrin/CD9­transforming growth factor interaction. Hence, CD9 can play a dual role in various types of cancer.

Insight into OroxylinA-7-O-ß-d-Glucuronide-Enriched Oroxylum indicum Bark Extract in Oral Cancer HSC-3 Cell Apoptotic Mechanism: Role of Mitochondrial Microenvironment.

Oroxylum indicum, of the Bignoniaceae family, has various ethnomedical uses such as an astringent, anti-inflammatory, anti-bronchitis, anti-helminthic and anti-microbial, including anticancer properties. The druggability of OI stem bark extract was determined by its molecular docking interactions with PARP and Caspase-3, two proteins involved in cell survival and death. Note that 50 µg/mL of Oroxylum indicum extract (OIE) showed a significant (p < 0.05%) toxicity to HSC-3 cells. MTT aided cell viability and proliferation assay demonstrated that 50 µg/mL of OIE displayed significant (p < 0.5%) reduction in cell number at 4 h of incubation time. Cell elongation and spindle formation was noticed when HSC-3 cells were treated with 50 µg/mL of OIE. OIE initiated DNA breakage and apoptosis in HSC-3 cells, as evident from DNA ladder assay and calcein/EB staining. Apoptosis potential of OIE is confirmed by flow cytometer and triple-staining (live cell/apoptosis/necrosis) assay. Caspase-3/7 fluorescence quenching (LANCE) assay demonstrated that 50 µg/mL of OIE significantly enhanced the RFU of caspases-3/7, indicating that the apoptosis potential of OIE is probably through the activation of caspases. Immuno-cytochemistry of HSC-3 cells treated with 50 µg/mL of OIE showed a significant reduction in mitochondrial bodies as well as a reduction in RFU in 60 min of incubation time. Immunoblotting studies clearly showed that treatment of HSC-3 cells with OI extract caused caspase-3 activation and PARP deactivation, resulting in apoptotic cell death. Overall, our data indicate that OIE is an effective apoptotic agent for human squamous carcinoma cells and it could be a future cancer chemotherapeutic target.

ω-6/ω-3 fatty acid ratio as an essential predictive biomarker in the management of type 2 diabetes mellitus.

OBJECTIVES: Intake of dietary fatty acid may play a major role in the prevention and management of lifestyle-related diseases such as type 2 diabetes mellitus (T2DM). Therefore, the aim of this study was to find an association between ω-6 to ω-3 fatty acid ratio and T2DM. METHODS: Fasting plasma glucose, glycated hemoglobin, and insulin were measured using commercially available kits. Fatty acid methyl esters were prepared using standard protocols. Delta-5 desaturase (D5D) and delta-6 desaturase (D6D) activities were determined from product-to-precursor ratios of individual fatty acids in plasma. Statistical analysis was performed using SPSS version 20. RESULTS: The ratio of ω-6 to ω-3 was higher in the group with diabetes (13:1) when compared with the group without diabetes (4:1) and was statistically significant (P < 0.0001). Further association studies showed that univariate model with the ω-6 to ω-3 ratio and a multivariate model with D5D, D6D, and ω-6 to ω-3 ratio could serve as predictive polyunsaturated fatty acid pathway models for T2DM. CONCLUSIONS: From the study results, it is evident that ω-6 to ω-3 fatty acid ratios can serve as essential predictive biomarkers in the management of patients with T2DM. This would not only help in management but would also aid in prevention of increased T2DM incidence in India. These results potentiate the need to maintain an ideal balance of ω-6 to ω-3, as prevention is always better than cure.

F-box protein FBXO16 functions as a tumor suppressor by attenuating nuclear ß-catenin function.

Aberrant activation of ß-catenin has been implicated in a variety of human diseases, including cancer. In spite of significant progress, the regulation of active Wnt/ß-catenin-signaling pathways is still poorly understood. In this study, we show that F-box protein 16 (FBXO16) is a putative tumor suppressor. It is a component of the SCF (SKP1-Cullin1-F-box protein) complex, which targets the nuclear ß-catenin protein to facilitate proteasomal degradation through the 26S proteasome. FBXO16 interacts physically with the C-terminal domain of ß-catenin and promotes its lysine 48-linked polyubiquitination. In addition, it inhibits epithelial-to-mesenchymal transition (EMT) by attenuating the level of ß-catenin. Therefore, depletion of FBXO16 leads to increased levels of ß-catenin, which then promotes cell invasion, tumor growth, and EMT of cancer cells. Furthermore, FBXO16 and ß-catenin share an inverse correlation of cellular expression in clinical breast cancer patient samples. In summary, we propose that FBXO16 functions as a putative tumor suppressor by forming an SCFFBXO16 complex that targets nuclear ß-catenin in a unique manner for ubiquitination and subsequent proteasomal degradation to prevent malignancy. This work suggests a novel therapeutic strategy against human cancers related to aberrant ß-catenin activation. © 2019 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.

Protein Phosphatase 1 Regulatory Subunit SDS22 Inhibits Breast Cancer Cell Tumorigenesis by Functioning as a Negative Regulator of the AKT Signaling Pathway.

Protein phosphatases play a crucial role in cell cycle progression, cell survival, cellular signaling, and genomic integrity. The protein phosphatase 1 (PP1) regulatory subunit SDS22 plays a significant role in cell cycle progression. A recent study showed that SDS22 plays a vital role in epithelial integrity and tumor suppression in Drosophila. However, its tumor suppressive activity remains obscure in the mammalian system. Here, for the first time, we show that SDS22 inhibits the growth of breast cancer cells through induction of apoptosis. SDS22 negatively regulates the AKT kinase signaling pathway through PP1. SDS22 associates predominantly with AKT and dephosphorylates the phospho Thr308 and phospho Ser473 through PP1 and hence abrogates the cell migration, invasion, and tumor growth. Thus, our study deciphers the long-standing question of how PP1 negatively regulates the AKT signaling pathway. Further, we observed a significant converse correlation in the expression levels of SDS22 and phospho form of AKT with reduced levels of SDS22 in the higher grades of cancer. Overall, our results suggest that SDS22 could be a putative tumor suppressor and replenishment of SDS22 would be an important strategy to restrict the tumor progression.

Glucose induced activation of canonical Wnt signaling pathway in hepatocellular carcinoma is regulated by DKK4.

Elevated glycemic index, an important feature of diabetes is implicated in an increased risk of hepatocellular carcinoma (HCC). However, the underlying molecular mechanisms of this association are relatively less explored. Present study investigates the effect of hyperglycemia over HCC proliferation. We observed that high glucose culture condition (HG) specifically activates canonical Wnt signaling in HCC cells, which is mediated by suppression of DKK4 (a Wnt antagonist) expression and enhanced ß-catenin level. Functional assays demonstrated that a normoglycemic culture condition (NG) maintains constitutive expression of DKK4, which controls HCC proliferation rate by suppressing canonical Wnt signaling pathway. HG diminishes DKK4 expression leading to loss of check at G0/G1/S phases of the cell cycle thereby enhancing HCC proliferation, in a ß-catenin dependent manner. Interestingly, in NOD/SCID mice supplemented with high glucose, HepG2 xenografted tumors grew rapidly in which elevated levels of ß-catenin, c-Myc and decreased levels of DKK4 were detected. Knockdown of DKK4 by shRNA promotes proliferation of HCC cells in NG, which is suppressed by treating cells exogenously with recombinant DKK4 protein. Our in vitro and in vivo results indicate an important functional role of DKK4 in glucose facilitated HCC proliferation.

Regulation of urokinase receptor expression by protein tyrosine phosphatases.

Urokinase-type plasminogen activator (uPA) and its receptor (uPAR) play a major role in several physiological processes such as cell migration, proliferation, morphogenesis, and regulation of gene expression. Many of the biological activities of uPA depend on its association with uPAR. uPAR expression and its induction by uPA are regulated at the posttranscriptional level. Inhibition of protein tyrosine phosphatase-mediated dephosphorylation by sodium orthovanadate induces uPAR expression and, with uPA, additively induces cell surface uPAR expression. Sodium orthovanadate induces uPAR by increasing uPAR mRNA in a time- and concentration-dependent manner. Both sodium orthovanadate and uPA induce uPAR mRNA stability, indicating that dephosphorylation could contribute to uPA-induced posttranscriptional regulation of uPAR expression. Induction of the tyrosine phosphatase SHP2 in Beas2B and H157 cells inhibits basal cell surface uPAR expression and uPA-induced uPAR expression. Sodium orthovanadate also increases uPAR expression by decreasing the interaction of a uPAR mRNA coding region sequence with phosphoglycerate kinase (PGK) as well as by enhancing the interaction between a uPAR mRNA 3' untranslated sequence with heterogeneous nuclear ribonucleoprotein C (hnRNPC). On the contrary, overexpression of SHP2 in Beas2B cells increased interaction of PGK with the uPAR mRNA coding region and inhibited hnRNPC binding to the 3' untranslated sequence. These findings confirm a novel mechanism by which uPAR expression of lung airway epithelial cells is regulated at the level of mRNA stability by inhibition of protein tyrosine phosphatase-mediated dephosphorylation of uPAR mRNA binding proteins and demonstrate that the process involves SHP2.

Salivary glycoproteins as indicators of oral diseases.

The present study deals with the estimation of total carbohydrate, protein bound carbohydrate, bound fucose and sialic acid along with total protein in disease conditions like gingivitis, periodontitis and their comparison with the normals.The neutral hexose values in gingivitis (8.08±2.20mg/100mg protein) and periodontitis (12.5±2.16mg/ 100mg protein) decreased significantly when expressed per 100 mg protein compared to normals (19.8±1.89mg/100mg protein). This might be because of higher protein concentration in these two clinical conditions. The ethanol insoluble hexose values were significantly reduced in both these conditions compared to controls (3.71±1.64,5.91±1.63,7.65±0.86mg/100mg protein respectively). The ethanol soluble hexose values were also found to be drastically reduced. This decrease in saliva appears to be characteristic feature of oral diseases. In gingivitis and periodontitis fucose level was found to be increased compared to normals when expressed as a function of salivary volume. However in terms of protein concentration the values in gingivitis (2.95±1.59), periodontitis (3.26±0.98) and normals (3.20±0.50mg/100mg) were not different. Sialic acid in ethanol insoluble fraction of salivary samples mg/100mg protein was found to be significantly reduced in both gingivitis (0.78±0.33) and periodontitis (0.95±0.31) compared to controls (1.92±0.33).