Tongue Cancer Cell Line Research Articles

Proteomics study of the serum biomarkers in tongue cancer

To search for specific serum biomarkers associated with tongue cancer by means of the serum proteomics technology. The tongue cancer cells of human tongue cancer cell line Tca8113 were subcutaneously inoculated into nude mice, while control nude mice were injected with phosphate-buffered saline. Serums from these two group of mice were collected for proteomic analysis using two-dimensional gel electrophoresis (2-DE) and mass spectrometry (MS). Comparing the serum 2-DE maps from the tumor-bearing mice with those produced from control mice, we found that squamous cell carcinoma antigen 1 was over expressed only in the serum of tumor-bearing mice. The squamous cell carcinoma antigen 1 may be of great potential as the biomarker of tongue cancer and as the potential therapeutic target for gene therapy.

Clinicopathologic significance of EpCAM expression in squamous cell carcinoma of the tongue and its possibility as a potential target for tongue cancer gene therapy

Epithelial adhesion molecule (EpCAM) is a transmembrane glycoprotein involved in intercellular adhesion. In particular, EpCAM appears to be overexpressed by the majority of human epithelial carcinomas, including colorectal, breast, head and neck, and hepatic carcinomas. We therefore hypothesized that EpCAM would be a good molecular target for cancer gene therapy. EpCAM protein expression in 48 primary tongue cancers and 10 normal oral mucosa was evaluated using anti-EpCAM immunohistochemistry, and correlation was examined with the clinicopathologic factors. In four human tongue cancer cell lines (SAS, HSC-2, OSC19 and OSC20), we investigated EpCAM expression by reverse transcription-polymerase chain reaction (RT-PCR). The invasive potential of cancer cells was evaluated using Matrigel invasion assay. Moreover, the effect of EpCAM inhibition was analyzed using RNA interference (RNAi). EpCAM overexpression was detected in 30 of 48 tongue cancers (62.5%), and was significantly higher in primary squamous cell carcinoma (SCC) of the tongue than in normal oral mucosa. The expression of EpCAM was significantly associated with tumor size, regional lymph node metastasis, histological differentiation and invasion pattern. Cancer cell lines with higher EpCAM expression had more invasive potential. Moreover, RNAi-mediated EpCAM reduction decreased the invasion potential and proliferation activity. These results indicated that the overexpression of EpCAM was correlated with a more aggressive phenotype of tongue cancer. Moreover, we suggested that EpCAM could be a molecular target, and that RNAi targeting EpCAM could be useful for tongue cancer gene therapy.

Suppressive effect of modified dominant negative RAS mutant on human cancer by gene transfer with non-viral vector

N116Y, H-RAS mutant, has dominant negative activity in the RAS function and a suppressive effect on the growth of various types of cancer cells. However, a replication error of N116Y is of potential concern for carcinogenesis in clinical application. To decease the concern, we constructed modified N116Y by deleting the carboxyl terminus, which is necessary for the oncogenic function of Ras. One of the C-terminal deletion mutants of N116Y, N116Y-Cdel2 showed a growth-suppressing effect on various human cancer cell lines in vitro: the cervical cancer cell line HeLa, the pancreatic cancer cell line PCI43, the colon cancer cell lines SW480 and LoVo, and the tongue cancer cell line SAS. In addition, the suppressive effect of N116Y-Cdel2 on LoVo cells was also observed in vivo using a non-viral gene transfer vector, HVJ envelope. Our experiments suggest that the modified N116Y is a potential candidate gene for human cancer gene therapy.

Overexpression of BLCAP induces S phase arrest and apoptosis independent of p53 and NF-κB in human tongue carcinoma

Bladder cancer-associated protein gene (BLCAP) is a novel candidate tumor suppressor gene identified from the human bladder carcinoma. Our previous studies have shown that BLCAP overexpression could inhibit cell growth by inducing apoptosis in HeLa cells [Zuo Z, Zhao M, Liu J, Gao G, Wu X: Tumor Biol 27: 221-226, 2006]. Such evidence suggests the alterations in BLCAP may play an important role in tumorigenesis. To further study the biological function of the BLCAP gene, we constructed a recombinant retroviral vector encoding BLCAP cDNA. Overexpressed BLCAP, via stable infection of exogenous BLCAP, resulted in growth inhibition of the human tongue cancer cell line Tca8113 in vitro, accompanied by S phase cell cycle arrest and apoptosis. The growth inhibition was correlated with up-regulation of p21(WAF1/CIP1 )expression and down-regulation of Bcl-XL and Bcl-2 expressions. However, p53 expression and NF-kappaB activity remained unchanged post infection. Furthermore, no changes in p53 phosphorylation at Ser46 and nuclear localization, which are critical to p53 function, were observed in BLCAP-overexpressed cells. Taken together, BLCAP may play a role not only in regulating cell proliferation but also in coordinating apoptosis and cell cycle via a novel way independent of p53 and NF-kappaB.

Growth suppression induced by Notch1 activation involves Wnt—β‐catenin down‐regulation in human tongue carcinoma cells

Involvement of Notch1 signalling in several cancers is well known, but its role in human tongue squamous cell carcinoma, one of the most common carcinomas of the human oral cavity, remains poorly characterized. Our studies demonstrated that constitutively over-expressed active Notch1, via stable transfection of exogenous ICN (intracellular fragment of Notch), resulted in growth suppression of the human tongue cancer cell line Tca8113 in vitro and in vivo, accompanied by G(0)-G(1) cell cycle arrest and apoptosis. Moreover, down-regulation of beta-catenin protein expression was observed in Tca8113 cells stably expressing active Notch1. Activated Notch1 also led to dramatic increase in p21(WAF1/CIP1) and p53 expression with decreases in Skp2 (S-phase kinase-associated protein 2) and Bcl-2 (B-cell lymphocytic-leukaemia proto-oncogene 2) expression, which may participate in the induction of apoptosis and cell cycle arrest. Since the effects of the Notch1 pathway are cell-type specific and context-dependent in cell types where Notch1 has an anti-proliferative effect, down-regulation of Wnt/beta-catenin signalling may be one of the mechanisms which induces apoptosis and cell cycle arrest.

The Antiproliferative Effect of Lidocaine on Human Tongue Cancer Cells with Inhibition of the Activity of Epidermal Growth Factor Receptor

Local anesthetics suppress proliferation in several cancer cells. The mechanism of the suppression, however, is unknown. Our previous study shows that lidocaine, at the level of tissue concentration under topical or local administration, has a direct inhibitory effect on the activity of epidermal growth factor receptor (EGFR), which is a potential target for antiproliferation in cancer cells. Therefore, we hypothesized that lidocaine would suppress the proliferation of cancer cells through the inhibition of EGFR activity. We investigated the effects of lidocaine (40-4000 microM) on proliferation of a human tongue cancer cell line, CAL27, which has a high level of EGFR expression, and also examined the effect of lidocaine on epidermal growth factor (EGF)-stimulated autophosphorylation of EGFR in CAL27 cells. A clinical concentration of lidocaine (400 microM) suppressed both serum-induced and EGF-induced proliferation of CAL27 cells and inhibited EGF-stimulated tyrosine kinase activity of EGFR without cytotoxicity. A larger concentration of lidocaine (4000 microM) showed cytotoxicity with an antiproliferative effect. We suggest that the inhibition of EGF-stimulated EGFR activity is one of the mechanisms of the antiproliferative effect of lidocaine on CAL27 cells. Lidocaine administered topically within the oral cavity for cancer pain relief may suppress the proliferation of human tongue cancer cells.

Effects of tea polyphenols on telomerase activity of a tongue cancer cell line: a preliminary study

The aim of this study was to determine, at the mRNA and protein levels, whether tea polyphenols (TPs) affect the expression of the human telomerase reverse transcriptase (hTERT) gene in the Tca8113 cancerous cell line. The expression of this gene was determined at the mRNA level by reverse transcription and polymerase chain reaction and at the protein level by Western blotting. The semi-quantitative scores of hTERT mRNA expression were analyzed by one-way analysis of variance. After 72 h of exposure to TPs, the mean (±SD) scores of hTERT mRNA expression in TP 0.1 g/l, TP 0.05 g/l and a control group were 0.32 ± 0.05, 0.41 ± 0.04 and 0.72 ± 0.05, respectively ( P < 0.05). The Western blot assay showed that TPs also decreased the expression of hTERT at the protein level. These results indicate that TPs reduce hTERT activity in the human Tca8113 cell line in a time- and dose-dependent manner, disabling telomerase activity and thereby terminating unlimited cancer cell proliferation. These findings suggest a mechanism behind TP's anticancer activity.

Serum proteomics study of the squamous cell carcinoma antigen 1 in tongue cancer

The identification of serum biomarkers as a means of the early diagnosis and finding possible therapeutic targets in cancers is of increasing interest. In the present study, cells of human tongue cancer cell line Tca8113 were subcutaneously inoculated into nude mice, while control nude mice were injected with phosphate-buffered saline. Two weeks after injection, serum from mice was collected for proteomic analysis using two-dimensional gel electrophoresis (2-DE) and mass spectrometry (MS). Comparing the serum 2-DE maps from the tumor-bearing mice with those produced from control mice, we found that squamous cell carcinoma antigen 1 was over-expressed only in tumor-bearing mice. Squamous cell carcinoma antigen 1 was also up-regulated in clinical tongue cancer patients by RT-PCR and Western-blotting. These results indicate that squamous cell carcinoma antigen 1 may be of great potential as the biomarker of tongue cancer and as the potential therapeutic target for gene therapy.

515 Induction of unique structural changes in guanine-rich DNA regions by the triazoloacridone C-1305, a topoisomerase II inhibitor with potent activity toward solid tumors

This study investigated the phenotypic stability and biological properties of two human tongue cancer cell lines after transduction of fluorescent proteins.The human tongue cancer cell lines UM1 and UM2 were cultured with GFP and RFP lentiviral particles stock for 72 h. Cells with successful transduction of fluorescent proteins were selected in a medium containing G418 antibiotics for two weeks. The proliferation rates of parental and transduced cell lines were evaluated by their population doubling time (PDT). Transduction efficiency was assessed by fluorescence microscope and flow cytometry. The transduced cells in passage 1, 2, 10, 20 and 30 were collected to check the stability of fluorescent protein expression. Phenotypic stability of the transduced cells was detected by means of cell morphology, cell surface markers and cell function evaluating essay.The proliferation rates of the transduced cell lines showed no significant difference compared to their parental cells. Successful transduction with high efficiency (99% up) was demonstrated. High fluorescence expression on both transduced cells was detected until the thirtieth generation. UM1 and UM1-GFP displayed mesenchymal cell characteristics, while UM2 and UM2-RFP cell lines showed properties characteristic of epithelial.Two human tongue cancer cell lines of epithelial and mesenchymal phenotype respectively, have been successfully labelled with green and red fluorescent proteins. The fluorescence maintained a high expression rate over thirty generations without influencing the original morphological phenotype and cadherin expression.

Microvascular architecture of human tongue cancer cell line transplanted subcutaneously in nude mice

Microvascular architecture of human tongue cancer cell line transplanted subcutaneously in nude mice

Differential Expression of Cytokeratin after Orthotopic Implantation of Newly Established Human Tongue Cancer Cell Lines of Defined Metastatic Ability

Two human tongue squamous cell carcinoma cell lines, SQUU-A and SQUU-B, were established from the same patient. Cervical lymph node metastasis was detected in the mice orthotopically implanted with SQUU-B (86.7%, 13/15), but not in those with SQUU-A (0/13). Histologically, SQUU-B showed invasive growth and intravasation in the tongue, whereas SQUU-A simply demonstrated expansive growth without intravasation. By Western blot analysis, nonmetastatic clone SQUU-A expressed cytokeratin (CK)13/4, 14, 16/6, 18/8, and 19, whereas a high metastatic clone SQUU-B expressed CK18/8 and 19. The reverse transcription-polymerase chain reaction technique showed that CK13/4 mRNA was expressed in both cell lines, but CK14 and 16 mRNA was expressed only in SQUU-A. CK13 was immunohistochemically expressed in both SQUU-A and SQUU-B transplanted into the tongues of nude mice; CK14 and 16 were detected in SQUU-A of the tongues, but not in SQUU-B. As seen in SQUU-B cell line, SQUU-B of the cervical lymph node metastasis did not exhibit CK13, 14, or 16. These results suggest that the loss or down-regulation of CK13, 14, or 16 is related to the invasive and metastatic ability of cancer. The cytoskeletal system is thus considered to be closely related to the malignant phenotype.

Study on the thermosensitivity of a tumor cell by microcalorimetry

Power-time curves of the growth of a tongue cancer cell line (CP 2) and a normal human embryonic lung cell line (Fu 2P 1) have been determined by a microcalorimeter at 37°C and 45°C, respectively. The experiments showed that the ratio of the maximal thermal power of both kinds of cell growth, P max ( CP 2, 37° C) P max ( Fu 2 P 1, 37° C) , equalled 1.74 at 37°C, while at 45°C, P max ( CP 2, 45° C) P max ( Fu 2 P 1), 45° C) = 0.464 . The ratio of the metabolic heat for both kinds of cell growing for 63 h at 37°C is, Q ( CP 2, 37° C) Q( Fu 2 P 1, 37° C) = 2.295 , while at 45°C after both kinds of cells grow for 15 h, Q( CP 2, 45° C) Q( Fu 2 P 1, 45° C) = 0.686 . As a comparison, Q( CP 2, 37° C) Q( CP 2, 45° C) = 1.734 , Q( Fu 2 P 1, 37° C) Q( Fu 2 P 1, 45° C) = 0.502 . The results indicate that the metabolic activity value of the tumor cell is distinctly higher than that of nontumor cell at 37°C, but lower at 45°C. By means of microcalorimetry, it is demonstrated that temperature has a remarkably selective destructuring effect of heat against tumor cell. The results of 6 other kinds of cancer cells and normal cells at different temperatures are also in agreement with the results obtained. Also, the power-time curves of the two passages of the tongue cancer cell (P 6 and P 7) are determined. The difference between the two passages is shown clearly on the power-time curves. It is concluded that microcalorimetry could be used as a powerful tool to characterize the passages of the cell.