Jiunn Liang Ko

Analysis of NQO1, GSTP1, and MnSOD genetic polymorphisms on lung cancer risk in Taiwan

We assessed the association of three genetic polymorphisms, NAD(P)H quinone oxidoreductase (NQO1), Glutathione-S-transferase P1 (GSTP1), and manganese superoxide dismutase (MnSOD), with lung cancer risk in 198 cases and 332 controls in Taiwan. Overall, NQO1 and MnSOD polymorphisms were not associated with an increased risk of lung cancer. Individuals carrying variant alleles of GSTP1 were at higher risk of squamous cell lung carcinoma (odds ratio, 1.63; 95% confidence interval, 0.96-2.74). When the groups were further stratified by smoking status following gender and histological type, the wild-type NQO1 was associated with lung adenocarcinoma among smokers but not among nonsmokers (odds ratio, 2.49; 95% confidence interval, 1.17-5.32). These results suggest that NQO1 plays a role in the development of cigarette smoking-associated lung adenocarcinoma. In addition, GSTP1 polymorphism was associated with the risk of squamous cell lung carcinoma in Taiwan.

MDM2 mRNA expression is a favorable prognostic factor in non-small-cell lung cancer.

MDM2 is one of the downstream target genes for transcriptional activation by the product of the p53 tumor‐suppressor gene. Transactivation of MDM2 gene expression is represented by the presence of a functional p53 protein. We hypothesized that MDM2 mRNA expression may be a more suitable prognostic factor than p53 or MDM2 protein expression and p53 gene mutations. In this study, expression of MDM2 mRNA, p53 protein, and MDM2 protein and mutations of the p53 gene were assessed in 81 lung tumor tissue specimens using RT‐PCR, immunohistochemistry, and direct sequencing among exons 5–8, respectively. By immunohistochemistry, 33 and 42 of 81 patients with p53 (40.7%) and MDM2 (51.5%) protein expression were found in lung tumor specimens, respectively. The p53 direct sequencing data indicated that 13 of 81 patients (16.0%) had p53 mutations. However, Kaplan‐Meier analysis showed that p53 protein and MDM2 protein expression and p53 mutation were not useful as prognostic factors. Interestingly, the survival of patients with MDM2 mRNA expression was longer than that of patients without MDM2 mRNA expression, though MDM2 mRNA expression was not associated with clinicopathological parameters, including tumor grade, tumor stage, tumor type, and TNM values. Moreover, Cox regression analysis showed that MDM2 mRNA expression was a significantly independent favorable prognostic factor in non‐small‐cell lung cancer (NSCLC) patients. Thus, measuring MDM2 mRNA expression using RT‐PCR may be a simple, useful approach for predicting the survival of NSCLC patients. Int. J. Cancer 89:265–270, 2000.

Dioscorea nipponica Makino inhibits migration and invasion of human oral cancer HSC-3 cells by transcriptional inhibition of matrix metalloproteinase-2 through modulation of CREB and AP-1 activity

Oral cancer mortality has increased during the last decade due to the difficulties in treating related metastasis. Dioscorea nipponica Makino, a popular folk medicine, exerts anti-obesity and anti-inflammation properties. However, the effect of this folk medicine on metastasis of oral cancer has yet to be fully elucidated. The present study demonstrates that D. nipponica extracts (DNE), at a range of concentrations (0-50 μg/mL), concentration-dependently inhibited migration/invasion capacities of human oral cancer cells, HSC-3, without cytotoxic effects. The anti-migration effect of DNE was also observed in two other OSCC cell lines, Ca9-22 and Cal-27. Zymography, real time PCR, and Western blotting analyses revealed that DNE inhibited matrix metalloproteinase-2 (MMP-2) enzyme activity, and RNA and protein expression. The inhibitory effects of DNE on MMP-2 proceeded by up-regulating tissue inhibitor of metalloproteinase-2 (TIMP-2), as well as suppressing nuclear translocation and DNA binding activity of cAMP response element-binding (CREB) and activating protein-1 (AP-1) on the MMP-2 promoter in HSC-3 cells. In conclusion, DNE inhibited the invasion of oral cancer cells and may have potential use as a chemopreventive agent against oral cancer metastasis.

Loss of telomerase activity may be a potential favorable prognostic marker in lung carcinomas

Many cancer and immortal cells exhibit telomerase activity that stabilizes telomere lengths, possibly contributing to cell immortality and carcinogenesis. The aim of this study was to elucidate the clinicopathological relationship between telomerase activity and telomerase reverse transcriptase subunit (hTERT) status in non small cell lung cancer. hTERT status in non small cell lung cancer using telomeric repeat amplification protocol (TRAP) and RT-PCR assay, respectively. Telomerase activity and hTERT were detected in 85.7 and 80.3% of cancerous tissues, respectively. Telomerase activity does not correlate with clinicopathological variables. However, there was an association between p53-correlated expression and hTERT negative status. Lung cancer patients without telomerase activity survived for a significantly longer period than those with telomerase activity. In addition, hTERT was not associated with the prognosis. TERT expression did not correlate well with any clinical parameter. Reactivated telomerase activity may be a poor prognostic factor in NSCLCs.

Human telomerase reverse transcriptase activated by E6 oncoprotein is required for human papillomavirus-16/18-infected lung tumorigenesis.

Purpose: Our recent report indicates that human papillomavirus (HPV)-16/18 E6 oncoprotein is expressed in lung tumors and is related to p53 inactivation. We further explored whether human telomerase reverse transcriptase (hTERT) transcription is up-regulated by E6 and contributes to lung tumor development. Experimental Design: Immunohistochemistry detected HPV-16 E6 oncoprotein in 135 lung tumors, and hTERT mRNA was evaluated by real-time reverse transcription-PCR and in situ hybridization, respectively. A small RNA interference (RNAi), Western blotting, and chromatin immunoprecipitation analysis were used to clarify whether hTERT transcription was regulated by c-Myc and Sp1. The telomerase activity and oncogenic potential of TL-1 with or without E6- or hTERT-RNAi was determined by real-time quantitative telomeric repeat amplification protocol analysis and soft-agar assay, respectively. Results: hTERT mRNA levels in E6-positive tumors, which were prevalent in females, nonsmokers, and adenocarcinomas, were significantly higher than in E6-negative tumors. In addition, hTERT mRNA levels in early tumors (stage I) were greater than levels in advanced tumors (stages II and III). Chromatin immunoprecipitation assay showed that Sp1 cooperated with c-Myc to activate hTERT transcription in TL-1 cells, which was similar to the SiHa cells. The telomerase activity of the TL-1 cells decreased concomitantly with the transfection of various doses of E6- or hTERT-RNAi. A soft-agar assay showed that the oncogenic potential of TL-1 cells was significantly reduced after being transfected with E6-RNAi. Moreover, a colony of TL-1 cells could not form after transfection with hTERT-RNAi. Conclusion: Transcriptional activation of hTERT by E6 oncoprotein is required for HPV-16/18-infected lung tumorigenesis.

A novel p53 mutant retained functional activity in lung carcinomas

The gene p53 is a critical tumor suppressor that can respond to multiple signals of cellular gatekeepers for growth and division. The mdm2 gene is one of the downstream target genes for transcriptional activation by the product of p53 tumor suppressor gene. Transactivation of mdm2 gene is represented by the presence of a functional P53 protein. To understand the biological function of mutant p53 in tumorigenesis, we constructed a number of p53 mutants by site-directed mutagenesis (H179Y, L194R, S240R, R249S, A276D, E286Q), followed by characterization of each P53 mutants ability to transactivate mdm2, bax and p21waf. The transactivation properties of p53 mutants were compared by co-transfection with pGL-3-mdm2, pGL-3-bax and pGL-3-p21waf into the P53 null cell line H1299 derived from a non-small cell lung carcinoma. Among them mt p53 S240R and E286Q were shown to have enhanced transactivating activity of pGL3-mdm2, at about 43.2 and 28.2% of the wt p53 vector, respectively, while the remaining four had nearly the same level of activity as the negative control did. Furthermore, data indicated that mt p53 S240R had as high an ability to suppress the growth of the p53 null cell line H1299 as wild type p53. Therefore, mutant p53 alone is an insufficient indicator of poor prognosis. Instead, functional p53 may affect lung cancer prognosis.

Induction of tubulin by Docetaxel is associated with p53 status in human non small cell lung cancer cell lines

Docetaxel (DOC), a member of the taxane family of anticancer drugs, binds to tubulin and produces unnaturally stable microtubules that induce cell death. DOC is used clinically alone or in combination with other compounds to treat advanced stages of cancer. We have treated the human lung cancer cell lines A549 and H1299 and human cervical cancer HeLa cells with low concentrations of DOC to characterize the response of β‐tubulin isotypes and p53 genes. The relationship between p53 function and DOC, acting through a microtubule‐based mechanism, was examined. We found that after 18‐hr treatment with DOC, β‐tubulin gene transcription was enhanced in p53‐null H1299 cells but not in A549 cells. Also, p53 RNA was strongly induced in the A549 cells. In addition, β‐tubulin levels also increased in the H1299 cells after the DOC treatment. Further demonstrating an association of DOC treatment with p53 and β‐tubulin, inhibition of p53 expression by interference RNA in A549 cells showed increasing β‐tubulin gene expression with DOC treatment. We also selected a clone from the H1299 cells that stably expressed p53, examined the β‐tubulin expression after DOC treatment and found an inhibition of β‐tubulin induction in these p53‐expressing cells. Our data suggest that the initial response of cells to DOC treatment involves p53; alternatively, in the absence of p53, tubulins may be transactivated. Selection of the DOC‐resistant A549 cells showed β‐tubulin expression was increased, in contrast to the initial response to the DOC treatment. From the initial and selection responses of β‐tubulin in cancer cells, it appears that there is a p53‐associated β‐tubulin expression as a result of the DOC treatment.

Prostate Cancer Mortality-To-Incidence Ratios Are Associated with Cancer Care Disparities in 35 Countries.

The variation in mortality-to-incidence ratios (MIRs) among countries reflects the clinical outcomes and the available interventions for colorectal cancer treatments. The association between MIR of prostate cancer and cancer care disparities among countries is an interesting issue that is rarely investigated. For the present study, cancer incidence and mortality rates were obtained from the GLOBOCAN 2012 database. The rankings and total expenditures on health of various countries were obtained from the World Health Organization (WHO). The association between variables was analyzed by linear regression analyses. In this study, we estimated the role of MIRs from 35 countries that had a prostate cancer incidence greater than 5,000 cases per year. As expected, high prostate cancer incidence and mortality rates were observed in more developed regions, such as Europe and the Americas. However, the MIRs were 2.5 times higher in the less developed regions. Regarding the association between MIR and cancer care disparities, countries with good WHO ranking and high total expenditures on health/gross domestic product (GDP) were significant correlated with low MIR. The MIR variation for prostate cancer correlates with cancer care disparities among countries further support the role of cancer care disparities in clinical outcome.

Upregulation of microRNA-4417 and Its Target Genes Contribute to Nickel Chloride-promoted Lung Epithelial Cell Fibrogenesis and Tumorigenesis

Nickel compounds have been classified as carcinogens and shown to be associated with induction of epithelial-mesenchymal transition (EMT) in fibrogenesis and tumorigenesis, as well as the crucial role of microRNAs (miRNAs) and their related genes in controlling EMT and cancer metastasis. Thus, the mechanisms involved in the regulation of EMT in nickel-treated cells are of potential interest in understanding lung fibrosis and tumor progression. We investigated the miRNA-dependent mechanisms involved in nickel-induced EMT in lung epithelial cells. Nickel increased miR-4417 expression and decreased its target gene TAB2 expression. Treatment of cells with TGF-β inhibitor SB525334 significantly blocked NiCl2 and TGF-β-induced EMT. The expression of miR-4417 was abolished by SB525334 in TGF-β-treated cells, but not in nickel-treated cells. Both overexpression of miR-4417 and silencing of TAB2 induced fibronectin expression, but did not reduce E-cadherin expression. Moreover, oral administration of nickel promoted lung tumor growth in nude mice that had received BEAS-2B transformed cells by intravenous injection. The induction of EMT by nickel is mediated through multiple pathways. Induction of abundant miR-4417 and reduction of TAB2 expression following nickel exposure and may be involved in nickel-induced fibronectin. These findings provide novel insight into the roles of nickel in fibrogenesis and tumor progression.

Correlation of plasma osteopontin and neutrophil gelatinase-associated lipocalin levels with the severity and clinical outcome of pelvic inflammatory disease

OBJECTIVEnTo investigate the correlation of two important inflammatory biomarkers, plasma osteopontin and neutrophil gelatinase-associated lipocalin (NGAL), with the severity and outcome of pelvic inflammatory disease (PID).nnnMATERIALS AND METHODSnSixty-one patients with PID, including 25 patients with tubo-ovarian abscess (TOA), were consecutively recruited. Their blood samples were tested for the concentrations of plasma osteopontin and NGAL using enzyme-linked immunosorbent assay. The associations of these biomarkers with TOA, length of hospitalization, and incidence of surgery were also analyzed.nnnRESULTSnPlasma osteopontin level was significantly increased in PID patients with TOA compared to PID patients without TOA (median 107.77xa0ng/mL vs. 72.39xa0ng/mL, pxa0=xa00.004). However, there was no significant difference for plasma NGAL. If the cutoff level of plasma osteopontin was set at 81.1xa0ng/mL, there was a 76.0% sensitivity and a 24.0% false negative rate in predicting TOA in PID patients. Plasma osteopontin significantly correlated with length of hospital stay (rxa0=xa00.467, pxa0<xa00.001), and this correlation was better than that of NGAL. However, neither biomarker was associated with incidence of surgery.nnnCONCLUSIONnPlasma osteopontin has a better correlation with TOA and length of hospitalization compared to NGAL. If plasma osteopontin level falls below 81.1xa0ng/mL, PID patients will have about a 20% chance of developing TOA. Incorporating plasma osteopontin, but not NGAL, will allow for an adjuvant diagnostic biomarker for TOA and predictor of length of hospital stay.