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Herpes simplex virus (HSV) infection is quite common in adults and neonates and is associated with oral mucocutaneous lesions and/or genital infections. Therefore, the aim of this present study was to determine the in-vitro cytotoxicity and anti-herpes simplex virus (1 and 2) activity of methanol extract of Strophanthus hispidus (S. hispidus ) DC (Stem bark) and his HPLC fingerprint profile. The cytotoxicity test on Vero cells was performed by MTT assay and various concentrations of extract less than the maximum nontoxic concentration were used against Vero cells for anti-HSV-1 and ant-HSV-2 effects by plaque assay. The CC50 values of methanolic extracts of S. hispidus (stem bark) and acyclovir against Vero cells were 94.46 µg/mL and 118.78 µg/mL, respectively. Whereas the EC50 and selectivity index values of this extract against herpes simplex virus 1 and herpes simplex virus 2 strains were 36.60 µg/mL (SI=2.58) and 39.47 µg/mL (SI=2.39), respectively. HPLC finger-printing of this extract was developed and showed seven major compounds including ascorbic acid, quercetin, resorcinol and gallic acid represented in large amount. In conclusion, the methanolic extract of Strophanthus hispidus DC(stem bark) has good antiherpetic activity against HSV- 1 and HSV-2 but it is also highly toxic. Therefore, it will be important to separate toxic molecules from those responsible of the antiherpetic activity by bio guided fractionation procedures.

We have previously developed a robust regimen for tolerance induction in murine models of islet cell transplantation using pre- and posttransplant infusions of donor splenocytes (SPs) treated with a chemical cross-linker ethylcarbodiimide (ECDI). However, the requirement for large numbers of fresh donor SPs for ECDI coupling impairs its clinical feasibility, and additionally, the compatibility of this tolerance regimen with commonly used immunosuppressive drugs is largely unknown. In the current study, we demonstrate that equivalent tolerance efficacy for islet cell transplantation can be successfully achieved not only with a significantly lower dose of ECDI-SPs than originally established but also with culture-expanded donor B-cells or with soluble donor antigens in the form of donor cell lysate, which is ECDI coupled to recipient SPs. We further demonstrate that tolerance induced by donor ECDI-SPs is dependent on a favorable apoptotic-to-necrotic cell ratio post-ECDI coupling and is not affected by a transient course of conventional immunosuppressive drugs including tacrolimus and mycophenolate mofetil. While splenic antigen-presenting cells of the recipient play an important role in mediating the tolerogenic effects of donor ECDI-SPs, splenectomized recipients can be readily tolerized and appear to employ liver Kupffer cells for uptaking and processing of the ECDI-SPs. We conclude that infusion of donor ECDI-SPs is a versatile tolerance strategy that has a high potential for adaptation to clinically feasible regimens for tolerance trials for human islet cell transplantation.

Six aromatic secondary metabolites, pestalone (1), emodin (2), phomopsilactone (3), pestalachlorides B (4), C (5), and D (6), were isolated from Pestalotiopsis sp. FKR-0115, a filamentous fungus collected from white moulds growing on dead branches in Minami Daito Island. The efficacy of these secondary metabolites against methicillin-resistant Staphylococcus aureus (MRSA) with and without meropenem (β-lactam antibiotic) was evaluated using the paper disc method and broth microdilution method. The chemical structures of the isolated compounds (1-6) were characterised using spectroscopic methods, including nuclear magnetic resonance and mass spectrometry. All six isolated compounds exhibited synergistic activity with meropenem against MRSA. Among the six secondary metabolites, pestalone (1) overcame bacterial resistance in MRSA to the greatest extent.

Pancreatic cancer is one of the most fatal types of cancer in developed countries. Most patients have locally advanced or metastatic cancerous lesions when they are diagnosed, due to the progressive, invasive and metastatic capacity of this disease to liver, lymph nodes and distant organs during early stages. Although the only curative therapy is complete surgical resection, the disease has usually already progressed by the time of diagnosis, and the majority of patients have metastatic disease. Therefore, palliative chemotherapy remains the only therapy for patients with progressive disease. Gemcitabine has been used for pancreatic cancer as the most effective anticancer drug. However, there are many cases resistant to gemcitabine. Thus, a better understanding of the molecular mechanisms of resistance to gemcitabine is essential to allow it to be used more effectively. Our previous proteomic studies demonstrated that the expression of heat-shock protein 27 (HSP27) was increased in gemcitabine-resistant pancreatic cancer cells and this might play a role in determining the sensitivity of pancreatic cancer to gemcitabine. Increased HSP27 expression in tumor specimens was related to resistance to gemcitabine and a shorter survival period in patients with pancreatic cancer. Furthermore, it has been shown that treatment strategies combining the HSP inhibitor KNK437 or interferon-γ (IFN-γ) with gemcitabine, were effective in gemcitabine-resistant pancreatic cancer cells in vitro. Furthermore, combined therapy of gemcitabine with IFN-γ of gemcitabine-resistant pancreatic cancer-bearing nude mice showed synergistic therapeutic effects on gemcitabine-resistant pancreatic cancer bearers. In this review, we summarize the current understanding of HSP27 and its role in gemcitabine resistance.

TS-1 is an oral anticancer agent containing two biochemical modulators for 5-fluorouracil (5-FU) and tegafur (FT), a metabolically activated prodrug of 5-FU. TS-1 has been recognized as an effective anticancer drug using standard therapies for patients with advanced pancreatic cancer along with gemcitabine. However, a high level of inherent and acquired tumor resistance to TS-1 induces difficulty in the treatment. To identify proteins linked to the TS-1-resistance of pancreatic cancer, we profiled protein expression levels in samples of TS-1-resistant and -sensitive pancreatic cancer cell lines by using two-dimensional gel electrophoresis (2-DE) and liquid chromatography-tandem mass spectrometry (LC-MS/MS). The cytotoxicity of a 5-FU/5-chloro-2,4-dihydroxypyridine (CDHP) combination towards pancreatic cancer cell lines was evaluated by MTS assay. Panc-1, BxPC-3, MiaPaCa-2 and PK59 showed high sensitivity to the 5-FU/CDHP combination (TS-1-sensitive), whereas PK45p and KLM-1 were much less sensitive (TS-1-resistant). Proteomic analysis showed that eleven spots, including T-complex protein 1 subunit beta, ribonuclease inhibitor, elongation factor 1-delta, peroxiredoxin-2 and superoxide dismutase (Cu-Zn), appeared to be down-regulated, and 29 spots, including hypoxia up-regulated protein 1, lamin-A/C, endoplasmin, fascin and annexin A1, appeared to be up-regulated in TS-1-resistant cells compared with -sensitive cells. These results suggest that the identified proteins showing different expression between TS-1-sensitive and -resistant pancreatic cancer cells possibly relate to TS-1-sensitivity. These findings could be useful to overcome the TS-1-resistance of pancreatic cancer cells.

The prognosis of patients with pancreatic cancer is very poor because of late diagnosis and the lack of response to various therapies. Pancreatic cancer is generally resistant to chemotherapy and is highly fatal. Gemcitabine (GEM) appears to be the only effective agent for treatment of pancreatic cancer. However, a high level of inherent and acquired tumor resistance makes the clinical impact of GEM modest. Proteomic differential display analysis for GEM-sensitive human pancreatic adenocarcinoma cell line KLM1 and GEM-resistant KLM1-R cells by using two-dimensional gel electrophoresis and liquid chromatography tandem mass spectrometry produced 33 protein spots. Of these, 23 were up-regulated and 10 were down-regulated in KLM1-R compared to KLM1 cells. The up-regulated proteins include acidic leucine-rich nuclear phosphoprotein 32 family member A, reticulocalbin-1, gamma-synuclein, microtubule-associated protein RP/EB family, sialic acid synthase, peptidyl-prolyl cis-trans isomerase A, far upstream element-binding protein 2 and catalase. The down-regulated proteins include far upstream element-binding protein 1, gamma-synuclein, galectin-1 and stathmin. Two spots of heat-shock protein 27 were up-regulated in KLM1-R cells. These results suggest an important complementary role for proteomics in the identification of proteins which may play a role in the poor response of pancreatic cancer to GEM.

Background: Gemcitabine (2'-deoxy-2'-difluorodeoxycytidine: Gemzar) (GEM) appears to be the only effective anticancer drug for pancreatic cancer, but it has little impact on outcome due to a high level of inherent and acquired tumor resistance. Our previous proteomic study demonstrated that the expression of three spots of heat-shock protein 27 (HSP27) was increased in GEM-resistant pancreatic cancer cells and could play a role in determining the sensitivity of pancreatic cancer to GEM., Materials and Methods and Results: In the present study, using one-dimensional and two-dimensional Western blotting, we elucidated that these three spots of HSP27 were phosphorylated in GEM-resistant pancreatic cancer cell line, KLM1-R., Conclusion: Phosphorylated HSP27 may play an important role in the resistance to GEM, and it could also be a possible biomarker for predicting the response of pancreatic cancer patients to treatment with GEM.