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Nitroglycerin (NTG)—a nitric oxide–donating drug—is traditionally administered via the sublingual route to treat acute myocardial angina attacks. NTG also increases tumor blood flow and, consequently, cancer drug delivery to tumor cells. In the homologous recombination pathway, radiation-sensitive 52 (Rad52) plays a crucial role in DNA repair by promoting the annealing of complementary single-stranded DNA and stimulating radiation-sensitive 51 (Rad51) recombinase activity. Pemetrexed—a multitargeted antifolate agent—exhibits satisfactory clinical activity in wild-type nonsquamous non-small-cell lung cancer (NSCLC) cells. However, the synergistic activity of combination therapy with NTG and pemetrexed against NSCLC cells has not yet been clarified. In 2 NSCLC cell lines (i.e. lung squamous cell carcinoma H520 and lung adenocarcinoma H1975 cells), NTG reduced Rad52 expression; in addition, decreased phospho-AKT and phospho-ERK1/2 protein levels were observed. Enhancement of AKT or ERK1/2 activity through transfection with a constitutively active AKT (AKT-CA) vector or constitutively active mitogen-activated protein kinase kinase 1 (MKK1-CA) vector increased the Rad52 protein level and cell survival, which were suppressed by NTG. The knockdown of Rad52 expression by using small interfering RNA or by inhibiting AKT and ERK1/2 activity enhanced the cytotoxicity and cell growth inhibition induced by NTG. Moreover, NTG synergistically enhanced the cytotoxicity and cell growth inhibition induced by pemetrexed in NSCLC cells; these effects were associated with AKT and ERK1/2 inactivation and, consequently, Rad52 downregulation in H520 and H1975 cells. The results provide a rationale for combining NTG and pemetrexed in lung cancer treatment to improve lung cancer control.

Elevated thymidine phosphorylase (TP) levels, a key enzyme in the pyrimidine nucleoside salvage pathway, in cancer cells, are related to a poor prognosis in a variety of cancers. Heat shock protein 90 (Hsp90) is a ubiquitous molecular chaperone that is involved in the stabilization and maturation of many oncogenic proteins. The aim of this study is to elucidate whether Hsp90 inhibitor 17-AAG could enhance tamoxifen- and erlotinib-induced cytotoxicity in nonsmall cell lung cancer (NSCLC) cells via modulating TP expression in two squamous NSCLC cell lines, H520 and H1703. We found that 17-AAG reduced TP expression via inactivating the MKK1/2-ERK1/2-mitogen-activated protein kinase (MAPK) pathway. TP knockdown with siRNA or ERK1/2 MAPK inactivation with the pharmacological inhibitor U0126 could enhance the cytotoxic and growth inhibitory effects of 17-AAG. In contrast, MKK1-CA or MKK2-CA (a constitutively active form of MKK1/2) vector-enforced expression could reduce the cytotoxic and cell growth inhibitory effects of 17-AAG. Furthermore, 17-AAG enhanced the cytotoxic and cell growth inhibitory effects of tamoxifen and erlotinib in NSCLC cells, which were associated with TP expression downregulation and MKK1/2-ERK1/2 signal inactivation. Taken together, Hsp90 inhibition downregulates TP, enhancing the tamoxifen- and erlotinib-induced cytotoxicity in H520 and H1703 cells.

Capsaicin, an ingredient of green and red bell peppers, shows anticancer activity in several malignant cell lines. Thymidylate synthase (TS) is a well-validated anticancer drug target in non-small cell lung cancer (NSCLC) cells. However, whether capsaicin and 5-fluorouracil (5-FU) induce synergistic cytotoxicity in NSCLC cells by regulating TS expression is unclear. This study investigated the cytotoxicity of capsaicin and 5-FU co-treatment on two hoursuman lung adenocarcinoma cell lines, H520 and H1703, and the underlying mechanisms. Capsaicin decreased TS expression in a p38 mitogen-activated protein kinase (MAPK) inactivation–dependent manner in H520 and H1703 cells. Enhancement of p38 MAPK activity by transfection with constitutive active mitogen-activated protein kinase kinase six vectors increased TS expression and cell survival. In addition, capsaicin and 5-FU co-treatment enhanced synergistic cytotoxicity and inhibited cell growth associated with TS downregulation and p38 MAPK inactivation in H520 and H1703 cells. Capsaicin and 5-FU co-treatment did not affect the cellular content of capsaicin. These results show that capsaicin may be combined with 5-FU to treat NSCLC.

Over the past century, stock identification, which is crucial for fisheries stock assessments, has relied heavily on intraspecies variations to differentiate management units. In recent years, however, DNA approaches have shed additional light on some aspects of the natural history and ecology of species and stocks. The Crescent Grunter Terapon jarbua is widely distributed across the Indo-Pacific region. It inhabits coastal waters with sandy substrates and tends to aggregate in estuaries. In the present study, we collected 96 individuals of T. jarbua from 10 locations around the shoreline of Taiwan as well as near Guangdong, China. A concatenated sequence (1,753 bp) of mtDNA (cytochrome c oxidase I and cytochrome b) was obtained from all individuals. We discovered two genetically distinct clades (lineages A and B) with different historical demographies occurring sympatrically except at the Yilan collection site, which was dominated by lineage A haplotypes. Connectivity within this region is high a...

This paper examines the performance of Taiwanese firms following acquisitions and finds that, when contrasted with the acquisitions that take place in the U.S., Taiwanese acquirers exhibit negative industry-adjusted accounting performance. The negative performance is mostly driven by firms with low growth opportunities, but is mitigated under more concentrated shareholdings and better board structures. These findings suggest that while weak corporate governance at the country-level may adversely affect the overall effectiveness of the takeover market in Taiwan, there is substantial cross-sectional variation in corporate governance at the firm-level. The evidence also shows that the announcement of an acquisition is accompanied by a positive announcement effect, and the poor operating performance might be related to the decreased assets turnover and sales growth rate.

Utilizing stock-market liberalization, we test whether managers exploit favorable market conditions to time their firms' IPOs, and whether or not the timing will have a persistent, negative impact on leverage. Using a sample of 235 Taiwanese IPOs over the 10-year period surrounding the first liberalization in the Taiwan stock market, a high-volatility, high-turnover, high-individual-trading emerging market, we first show that liberalization substantially reduces the cost-of-equity capital. We then provide evidence that the going-public decision for post-liberalization IPOs is consistent with equity market timing, but that it fails to influence the debt ratio.

Using Taiwanese equity data, we find that value-minus-growth strategies (HML) earn significantly positive expected returns, and that the value spread in B/M is widened following a financial crisis. Value firms disinvest more than growth firms in bad times. The HML betas are higher for periods of higher expected equity premium, higher market volatility, and lower GDP growth. Furthermore, while the HML betas are negative and positive for the pre- and post-crisis sample, respectively, the value (growth) betas increase (decrease) from pre- to post-crisis period. Also, the beta-premium sensitivity is positive for HML and value stocks, and negative for growth stocks.

PurposeThe purpose of the paper is to investigate the price interrelationship between the Taiwanese and US financial markets.Design/methodology/approachThe trivariate GJR‐GARCH (1,1) model and event study were employed to investigate volatility asymmetry and overreaction phenomenon, respectively.FindingsThe empirical results show that return volatility reveals the asymmetric phenomenon, and the holding period returns on US index futures from the opening of the US index futures electronic trading to the opening of the Taiwanese stock market are an important reference for investors in the Taiwanese stock market. Additionally, the paper presents an overreaction of the Taiwan Stock Exchange Capitalization Weighted Stock Index to a drastic price rise of E‐min NASDAQ 100 Index futures at the opening of the Taiwanese stock market.Research limitations/implicationsThis paper deletes the observations arising from the different national holidays of the USA and Taiwan, to have the same number of observations in both markets, which might contaminate the empirical results.Practical implicationsInvestors in the Taiwanese stock market tend to pay more attention to the fluctuations in the share prices of high‐technological companies in the USA.Originality/valueMost of the previous studies regarding price transmission between the Taiwanese and US stock markets focused mainly on the Taiwanese market reactions to the overnight returns of the US market. This paper enlarges the current field by examining the lead‐lag relationship, the volatility asymmetry, and the overreaction phenomenon between the Taiwanese and US financial markets according to the most updated US stock index information.

Stock price volatility increases in times of political crisis. In examining the effects of corporate governance and performance on price volatility and the market's overreaction during the political crisis triggered by the controversial Taiwan presidential election of 2004, our results show that companies with better corporate governance or performance experience less price volatility and less increase in volatility during such a crisis. Furthermore, the results show that corporate performance and ownership structure have significant effects on the stock price overreaction.

This paper proposes that the value of voting rights can be measured as the abnormal return of the date after the ex-voting rights date. The merit of this method is that it is applicable to all publicly traded firms. Whatever the expected return model is adopted, the vote value hypothesis of Manne (1962) is hold by using a sample of firms listed on Taiwan Stock Market whose annual shareholder meetings have a board election. Moreover, the result shows that the value of voting rights is negatively related to prior year’s market value of equity, managerial equity ownership, and return on asset. It is consistent with the hypothesis that the source of vote value comes from private benefit of control and improved management