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We reported previously that L-methioninase targeted to the urokinase receptor of MCF-7 breast cancer cells is significantly more effective in inhibiting cell proliferation and migration than free L-methioninase both in vitro and in vivo. L-methioninase was targeted by linking at its amino terminus to an amino-terminal fragment (ATF) of urokinase. The ATF was selected for targeting because is has previously been shown not to internalize within the cells. The present study was designed to determine the effectiveness of targeting L-methioninase to a cancer cell receptor that is internalizing in comparison with ATF-methioninase, which does not internalize. Transforming growth factor-[alpha] (TGF-[alpha]) was selected for targeting to the epidermal growth factor receptor which is overexpressed in numerous cancer cell lines and is an internalizing receptor. Two fusion proteins, ATF-methioninase and TGF-methioninase (TGF-a linked to the amino terminus of L-methioninase), were produced by recombinant methods and purified. In an in vitro culture wounding assay over 3 days to measure cell proliferation and migration of MCF-7 breast cancer cells and PC-3 prostate cancer cells, both fusion proteins inhibited the proliferation and migration of both cancer cell lines. However, the inhibition was significantly greater for ATF-methioninase compared to TGF-methioninase, especially at treatment days 2 and 3. These results indicate that, for a fixed dosage of the fusion protein, it is more advantageous to have L-methioinase bind to a receptor and remain externalized, rather than to bind to a receptor which leads to internalization of L-methioninase. Further, it may be advantageous to target other anticancer agents to the urokinase receptor on the cancer cell surface by means of the amino-terminal fragment of urokinase. Key words: Breast cancer, prostate cancer, L-methioninase, transforming growth factor-a, urokinase amino-terminal fragment, INTRODUCTION Methionine-dependence is a metabolic defect of cancer cells that is under investigation for the treatment of cancer. Many cancer cell lines have been found to have this defect [1]. [...]

In a previous study we compared the influence of several growth factors on breast cancer cells in culture and observed that epidermal growth factor (EGF) enhanced the invasiveness of estrogen receptor-positive breast cancer cells. The objective of the present study was to determine the influence of three unique antiestrogens on EGF-mediated movement of human breast cancer cells. The rate of movement of MCF-7 breast cancer cells was measured using time-lapse videomicroscopy (TLVM). The MCF-7 cells were pretreated with antiestrogen (either tamoxifen, ICI-182-780 (ICI) or 1,1-dichloro-cis-2,3-diarylcyclopropane (AII)) at 10–6 mol/l for 4 days, and then treated with EGF (10–10 mol/l) immediately prior to TLVM. EGF enhanced the motility of the MCF-7 cells at 30–90 min post-administration. However, EGF-mediated motility of the MCF-7 cells was inhibited by antiestrogen pretreatment, with TAM and ICI producing complete inhibition of EGF-induced motility. In conclusion, this study demonstrates that EGF enhances the rate of movement of MCF-7 breast cancer cells and that antiestrogen pretreatment inhibits EGF-mediated motility. Copyright © 2007 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Edible protein was prepared from avocado oil processing by-products. • Physicochemical and functional properties of avocado protein were investigated. • Oil-in-water emulsions stabilized by avocado protein. • Avocado oil processing by-products is a sustainable protein resource. Abstract Avocado (Persea americana) is a tropical fruit that has drawn great interest its oil for foods and cosmetic industries; however, avocado oil processing by-product is a potential source of edible protein. Herein, edible protein was prepared from defatted avocado meal, and it's physicochemical, functional and emulsion properties were investigated. The avocado protein showed U-shaped exhibiting strong effect of pH, and a minimum solubility being observed at pH 4.5, confirming the isoelectric point of avocado protein. Nutritionally, the avocado protein contains all the essential amino acids. Avocado protein provided higher water and oil absorption capacities, higher radical scavenging capacity but lower in-vitro digestibility compared with soy protein. Furthermore, the avocado protein as emulsifier afforded a stability oil-in-water emulsion system, resulting in a greater emulsifying stability than that of soy protein. The present results highlight the potential source of edible protein from avocado oil processing by-products for functional food ingredients. [ABSTRACT FROM AUTHOR]

Abstract Lots of bananas were wasted before commercialization. It is necessary to search potential industrial applications of banana. In the present study, starches from seven banana cultivars (labeled as A–G) were isolated and then characterized. These starches presented different and irregular shapes, such as sphere, long spheroid and polygonal granules. The distribution of size and analyses of average molecular weight showed more small granules in samples B, D, F and G than other samples. The amylose content varied from 22.59% to 38.40%. The crystal types of these starches were a mixture of B-type and C-type, and the relative crystallinity varied greatly. The differential scanning calorimetry (DSC) results showed that the onset temperature of gelatinization increased as follows: A < B < E < C ≈ D < F. The maximum viscosity of banana starch decreased as follows: G > C > D > F > E = B > A. The in vitro digestibility test showed that the content of resistant starch was very high in banana starches. These results would be useful to the application of those starches in food and nonfood industries. [ABSTRACT FROM AUTHOR]