In addition to the known function in the glycolytic pathway, phosphoglycerate kinase 1 (PGK‐1) promotes reduction of plasmin disulfide bonds leading to angiostatin formation and inhibition of tumor angiogenesis. In this study, the effects of PGK‐1 on anti‐ tumor immunity against lung cancer were evaluated using the Tet‐Off control of PGK‐1 expression in the Lewis lung carcinoma (LLC‐1). There was no significant difference in cell proliferation between parental LLC‐1 and LLC‐1 transduced with PGK‐1 (PGK‐LLC‐1). However, expression of PGK‐1 was found to limit tumor growth in mice subcutaneously injected with the cell lines and tumor growth was restored after doxycycline treatment. In addition, the cell invasion ability of PGK‐LLC‐1 became weaker than that of LLC‐1. Expressions of COX‐2, TGF‐β1 and PGE2 were all found to be down‐regulated in PGK‐LLC‐1. PGK‐LLC‐1 cells treated with doxycycline recovered their COX‐2 protein expression. In the presence of conditioned medium from PGK‐LLC‐1, the endothelial cell migration was reduced. Moreover, PGK‐LLC‐1 also stimulated T lymphocytes to express higher levels of Th1 cytokine (IFN‐γ) and lower levels of IL‐10 in comparison with parental LLC‐1. PGK‐LLC‐1 cells restored the growth rate in immunodeficient mice when compared with the growth rate in normal mice. In the tissue sections, reduced COX‐2 expressions and marked infiltrated CD3 T lymphocytes were observed in the PGK‐LLC‐1 injected group. These findings indicate that overexpression of PGK‐1 in LLC‐1 reduces the COX‐2 expression, and, in turn, affect PGE2, cell invasion, angiogenesis, and the immune functions, and finally inhibit the tumor progression. © 2008 Wiley‐Liss, Inc.

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Four previously unreported chemical entities, boydone A (1), boydone B (2), botryorhodine F (3), and botryorhodine G (4), along with five known compounds, fusidilactone A (5), (R)-(-)-mevalonolactone (6), (R)-(-)-lactic acid (7), ovalicin (8), and botryorhodine C (9), were isolated from the ethyl acetate extracts of the fermented broths of the fungal strain Pseudallescheria boydii NTOU2362. The structures of 1-9 were characterized on the basis of their spectroscopic data analyses. The absolute configurations of 1 and 2 were established by comparison with the literature and the modified Mosher's method. The growth inhibitory activities of 1-9 against the A549 non-small-cell lung cancer cell line were evaluated, and 2 and 8 exhibited moderate to potent bioactivities with GI₅₀ values of 41.3 and 4.1 μM, respectively, in comparison with fluorouracil (GI₅₀ = 3.6 μM).

A cDNA encoding chicken cystatin was cloned into the pET-23a(+) expression vector and then transformed into Escherichia coli AD494(DE3)pLysS expression host. An active soluble form of cystatin was expressed in the cytoplasm of E. coli induced by isopropyl beta-D-thiogalactopyranoside. The recombinant chicken cystatin was purified to electrophoretic homogeneity by a simple and rapid method involving heat treatment and Sephacryl S-100 gel filtration chromatography. The recombinant cystatin behaved as a thermal-stable protein and exhibited papain-like protease inhibition activity comparable to the natural chicken cystatin.