Shu-Hui Lin

Casein Kinase 1 Epsilon Expression Predicts Poorer Prognosis in Low T-Stage Oral Cancer Patients

Casein kinase 1 is a group of ubiquitous serine/threonine kinases that are involved in normal cellular functions and several pathological conditions, such as DNA repair, cell cycle progression, cytokinesis, differentiation, and apoptosis. Recent studies have indicated that casein kinase 1-epsilon (CK1ɛ) and casein kinase 1-delta (CK1δ) expression has a role in human cancers. We investigated the associations between CK1ɛ and CK1δ expression and the clinical parameters of oral cancer using immunohistochemical study methods on oral squamous cell carcinoma specimens. The results of our immunohistochemical analysis showed that the loss of CK1ɛ expression was greatly associated with a poor four-year survival rate in oral cancer patients (p = 0.002). A Kaplan-Meier analysis showed that patients who had a loss of CK1ɛ expression had a considerably poorer overall survival rate than patients who had positive CK1ɛ expressions (p = 0.022). A univariate analysis revealed that patients who had a loss of CK1ɛ expression had considerably poorer overall survival (OS) than patients who had positive expression (p = 0.024, hazard ratio (HR) = 1.7). In conclusion, our data indicated that the loss of cytoplasmic CK1ɛ expression is greatly associated with poor survival and might be an adverse survival factor.

Decreased Kruppel-like factor 4 (KLF4) expression may correlate with poor survival in gastric adenocarcinoma.

Kruppel-like factors (KLFs) play either anti- or pro-proliferation roles in different human cancers. Here, we investigated the expression of KLF4 in gastric cancers and its correlation with clinicopathological parameters and overall survival. KLF4 expression was measured in 118 surgical specimens by immunohistochemical microarray assay. No association of cytoplasmic KLF4 expression with gender, TNM status, stage, survival, and pathological type was found. Using Kaplan–Meier analysis, significantly higher overall survival rate was observed in patients with high cytoplasmic KLF4 expression compared to low cytoplasmic KLF4 expression. Univariate analysis revealed that cytoplasmic KLF4 expression, grade, histological type, lymph node metastasis, and stages were correlated to longer overall survival. Our results suggest that KLF4 may play an anti-oncogenic role in gastric tumorigenesis.

Cathepsin B Expression and the Correlation with Clinical Aspects of Oral Squamous Cell Carcinoma

Background Cathepsin B (CTSB), a member of the cathepsin family, is a cysteine protease that is widely distributed in the lysosomes of cells in various tissues. It is overexpressed in several human cancers and may be related to tumorigenesis. The main purpose of this study was to analyze CTSB expression in oral squamous cell carcinoma (OSCC) and its correlation with patient prognosis. Methodology/Principal Findings Tissue microarrays were used to detect CTSB expression in 280 patients and to examine the association between CTSB expression and clinicopathological parameters. In addition, the metastatic effects of the CTSB knockdown on two oral cancer cell lines were investigated by transwell migration assay. Cytoplasmic CTSB expression was detected in 34.6% (97/280) of patients. CTSB expression was correlated with positive lymph node metastasis (p = 0.007) and higher tumor grade (p = 0.008) but not with tumor size and distant metastasis. In addition, multivariate analysis using a Cox proportional hazards model revealed a higher hazard ratio, demonstrating that CTSB expression was an independent unfavorable prognostic factor in buccal mucosa carcinoma patients. Furthermore, the Kaplan–Meier curve revealed that buccal mucosa OSCC patients with positive CTSB expression had significantly shorter overall survival. Moreover, treatment with the CTSB siRNA exerted an inhibitory effect on migration in OC2 and CAL27 oral cancer cells. Conclusions We conclude that CTSB expression may be useful for determining OSCC prognosis, particularly for patients with lymph node metastasis, and may function as a biomarker of the survival of OSCC patients in Taiwan.

Low/negative expression of DDX3 might predict poor prognosis in non-smoker patients with oral cancer

OBJECTIVE DDX3 has diverse biological functions in translation control, cell growth regulation, and tumor progression. Oral squamous cell carcinoma (OSCC) is a common malignant tumor worldwide with a poor clinical prognosis. The impact of DDX3 expression in OSCC is seldom discussed. MATERIALS AND METHODS Tumor tissues and adjacent normal tissues were obtained from 324 patients with OSCC. In this study, we used immunohistochemical staining methods to investigate the associations between DDX3 expression and the clinicopathological characteristics of OSCC. RESULTS Low/negative DDX3 expression in tumor cells was significantly associated OSCC patient characteristics including male gender (P < 0.001), smoking (P < 0.001), alcohol consumption (P < 0.001), betel quid chewing (P = 0.002), poor relapse-free survival (P = 0.001), and poor overall survival (OS) (P = 0.001). Patients with low/negative DDX3 expression, and particularly non-smoker OSCC patients, had significantly worse OS as defined by the log-rank test (P = 0.020 for all cases; P = 0.008 for non-smoker patients). In non-smoker patients with OSCC, low/negative DDX3 expression in tumor cells was associated with poor prognosis (P = 0.024) and a 3.802-fold higher death risk, as determined by Cox regression. CONCLUSIONS Low/negative DDX3 expression in tumor cells was significantly associated with aggressive clinical manifestations and might be an independent survival predictor, particularly in non-smoker patients with OSCC.

Epigenetic silencing of the NR4A3 tumor suppressor, by aberrant JAK/STAT signaling, predicts prognosis in gastric cancer

While aberrant JAK/STAT signaling is crucial to the development of gastric cancer (GC), its effects on epigenetic alterations of its transcriptional targets remains unclear. In this study, by expression microarrays coupled with bioinformatic analyses, we identified a putative STAT3 target gene, NR4A3 that was downregulated in MKN28 GC daughter cells overexpressing a constitutively activated STAT3 mutant (S16), as compared to an empty vector control (C9). Bisulphite pyrosequencing and demethylation treatment showed that NR4A3 was epigenetically silenced by promoter DNA methylation in S16 and other GC cell lines including AGS cells, showing constitutive activation of STAT3. Subsequent experiments revealed that NR4A3 promoter binding by STAT3 might repress its transcription. Long-term depletion of STAT3 derepressed NR4A3 expression, by promoter demethylation, in AGS GC cells. NR4A3 re-expression in GC cell lines sensitized the cells to cisplatin, and inhibited tumor growth in vitro and in vivo, in an animal model. Clinically, GC patients with high NR4A3 methylation, or lower NR4A3 protein expression, had significantly shorter overall survival. Intriguingly, STAT3 activation significantly associated only with NR4A3 methylation in low-stage patient samples. Taken together, aberrant JAK/STAT3 signaling epigenetically silences a potential tumor suppressor, NR4A3, in gastric cancer, plausibly representing a reliable biomarker for gastric cancer prognosis.

MMP-11 promoted the oral cancer migration and FAK/Src activation

Matrix metalloproteinase-11 (MMP-11) has been observed in most invasive human carcinomas. The current study investigated the association between the clinicopathological characteristics and MMP-11 expression in oral squamous cell carcinoma (OSCC) patients. Immunohistochemistry (IHC) staining was performed to assess MMP-11 expression in 279 patients with OSCC. In addition, the metastatic effects of the MMP-11 overexpression on the OSCC cells were also investigated. We found that MMP-11 expression was present in 118/279 (42.3%) cases and expression of MMP-11 was associated with higher incidence of lymph node metastasis and worse grade of tumor differentiation. Importantly, OSCC patients with strong expression of MMP-11 had a significantly lower survival rate (p=0.010). Furthermore, MMP-11 overexpression in OSCC cells increased in vitro cell migration. Mechanistically, MMP-11 increased the cell motility of OSCC cells through focal adhesion kinase/Src kinase (FAK/Src) pathway. In conclusion, our results revealed that the MMP-11 expression in OSCC samples can predict the progression, especially lymph node metastasis, and the survival of OSCC patients in Taiwan.

Norcantharidin induce apoptosis in human nasopharyngeal carcinoma through caspase and mitochondrial pathway

While Nasopharyngeal carcinoma (NPC) is uncommon in western countries, it is endemic in Southeast Asia and Southern China. Previous study of norcantharidin (NCTD), isolated from blister beetles, has proved its anticancer effect on various tumors. However, the effect of NCTD in NPC has never been studied. The purpose of this study is to inspect the suppression activity of NCTD on NPC, along with the underlying mechanism. NPC cell line NPC‐BM was treated with NCTD. NCTD remarkably inhibited proliferation and induce apoptosis in NPC‐BM cell. Activation of caspase‐3, −8, −9 was observed through western blotting. The expression of antiapoptotic protein Bcl‐XL was significantly reduced, but expression of proapoptotic protein Bak was increased after treatment of NCTD. The cytotoxic effect of NCTD on NPC‐BM cell is mainly due to apoptosis, mediated by caspase and mitochondrial pathway. These results suggested that NCTD could be a potential anticancer agent for NPC.

Osthole induces human nasopharyngeal cancer cells apoptosis through Fas-Fas ligand and mitochondrial pathway

Nasopharyngeal carcinoma (NPC) is endemic in Southern China and Southeast Asia. The present study investigated the activity of osthole in suppressing NPC along with the underlying mechanism. Cell growth inhibition was measured using the MTT assay. Apoptosis was detected through 4ʹ,6‐diamidino‐2‐phenylindole staining and flow cytometry. Western blotting was used to identify the signaling pathway. Osthole markedly inhibited cell proliferation and induced apoptosis in the NPC cell line. Western blotting results revealed the increased activation of caspases 3, 8, and 9 and poly (ADP‐ribose) polymerase. Osthole treatment significantly reduced the expression of the antiapoptotic protein Bcl‐2 and increased the expression of the proapoptotic proteins Bax, Bak, BimL, BimS, and t‐Bid. Osthole treatment also increased the expression of Fas, FADD, TNF‐R1, TNF‐R2, DcR2, RIP, and DR5. In addition, osthole treatment significantly increased the expression levels of phosphorylated ERK1/2 and JNK1/2. These results suggested that osthole exerts cytotoxic effects on NPC cell lines mainly through apoptosis mediated by the Fas–Fas ligand and mitochondrial pathway. Osthole could be a potential anticancer agent for NPC.

Coronarin D induces reactive oxygen species-mediated cell death in human nasopharyngeal cancer cells through inhibition of p38 MAPK and activation of JNK

Background and Purpose Nasopharyngeal carcinoma (NPC) belongs to squamous cell carcinoma that occurs in the epithelial lining of the nasopharynx. Because of the anatomical position close to the cervical lymph node, some patients have a distant metastasis at the time of diagnosis that leads to treatment failure. Although early stages have a high curability and excellent prognosis, advanced NPC urgently requires new drugs developed to reinforce the effectiveness of therapy without noticeable side effects. Experimental approach Coronarin D (CD), a natural product extracted from the rhizomes of Hedychium coronarium, has been reported to possess anticancer potential. The aim of the present study was to determine the anticancer activity of CD and further elucidate the underlying molecular mechanisms. Key Results In this study, we first demonstrated that CD potently suppressed cell viability in various NPC cell lines. Treatment of cells with CD induced G2/M arrest, apoptosis, and autophagy. Further studies showed that CD increased the production of reactive oxygen species and subsequently activated both autophagy and apoptosis. Moreover, we found that CD-induced activation of p38 and JNK constituted major mechanisms involved in the apoptosis and autophagy triggered by CD. In particular, inhibition of autophagy could strengthen the cytotoxicity of CD, implying that autophagy seems to play a valuable survival and protective role in cancer cells. Conclusions & Implications These findings provide a promise for the use of CD in combination with autophagy inhibitors for treatment of human NPC cell lines.

Early Assessment of Colorectal Cancer by Quantifying Circulating Tumor Cells in Peripheral Blood: ECT2 in Diagnosis of Colorectal Cancer

Circulating tumor cells (CTCs) in peripheral blood is an indication of poor prognosis for patients with different cancer types. However, most of the available technologies for detecting CTCs show low sensitivity and specificity. Therefore, we attempted to find an alternative marker for CTCs of colorectal cancer. We have directly extracted RNA from CTCs contained in 1.5 mL peripheral blood from 90 colorectal cancer patients and 151 healthy donors, and screened these samples for candidate marker genes by nested real-time quantitative polymerase chain reaction (PCR). From genes selected from a public database of microarray analyses, we successfully identified epithelial cell transforming sequence 2 oncogene (ECT2) as a gene that exhibits high differential expression ratios (p < 0.01). ECT2 displays good sensitivity and specificity, with an area under the curve (AUC) value of 0.821. This marker gene also has a high detection rate in patients with serum carcinoembryonic antigen (CEA) concentrations below the diagnostic threshold of 5 ng/mL. The expression of ECT2 can therefore serve as an alternative measurement that can compensate for the inadequacy of the current CEA test in the diagnosis and monitoring of colorectal cancer patients.