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BB, a new EGFR inhibitor, exhibits prominent anti-angiogenesis and antitumor activities.

Cancer Biol Ther. 2009 Sep 6; 8(17): Sun QM, Miao ZH, Lin LP, Gui M, Zhu CH, Xie H, Duan WH, Ding JAberrant activation of the epidermal growth factor receptor (EGFR) is closely associated with malignant progression of tumors. EGFR inhibitors have been used successfully in clinic in the treatment of solid tumors. In the present study, we revealed that BB, a new synthetic quinonazoline derivative, was a potent EGFR inhibitor. BB selectively inhibited EGFR with a IC(50) value of 50 +/- 37 nM, at least 32-fold more potent than suppressed all other 10 tested receptor tyrosine kinases including the same family member ErbB2 (IC(50) = 5.6 +/- 3.2 muM). BB effectively abrogated autophosphorylation of the EGF-stimulated EGFR and phosphorylation of its key downstream signaling molecules ERK and AKT in A549 cells. BB was shown to suppress EGF-stimulated proliferation of A549 cells with an apparently lower IC(50) value (0.33 +/- 0.07 muM) than that (2.7 +/- 0.4 muM) for the serum-stimulated cells. BB also inhibited the EGF-independent proliferation of a panel of tumor cells. In addition, BB exhibited anti-angiogenesis activity, as evidenced by antagonizing EGF-induced HMEC-1 migration in vitro, blocking HMEC-1 tube formation, and inhibiting microvessel sprouting from rat aortic rings. Most importantly, BB prominently inhibited in vivo tumorigenesis of NIH3T3 cells specifically driven by the activation-mutated EGFR genes. As reported, normal NIH3T3 cells lack tumorigenicity in nude mice. NIH3T3 cells transfected with the EGFR gene with activating mutation (A750P or L858R) produced rapidly growing xenografts in nude mice. BB, when given orally at 100 mg/kg consecutively for 2 weeks, prominently inhibited the growth of the xenografts and reduced the number of microvessels. Taken together, the data indicate that BB is a new selective EGFR inhibitor with potent antitumor activity, revealing its potential as a promising anticancer candidate.

[Role of PKCbeta in the malignant tumors and enzastaurin, a PKCbeta inhibitor]

Yao Xue Xue Bao. 2009 May; 44(5): 449-55Li XY, Chen XGProtein kinase C beta (PKCbeta) is a multifunctional serine/threonine protein kinase, which plays an important role in many cell signaling pathways. PKCbeta takes part in multiple physiological processes, including regulation of the cell cycle, differentiation, proliferation, apoptosis and angiogenesis. Increased PKCbeta activity has been observed in many human cancers, such as colon, breast and haematological malignancies. At present, Enzastaurin is mostly studied in preclinical and clinical studies, which is a selective PKCbeta inhibitor. This review focuses on the functional properties of PKCbeta, its role played in tumors and Enzastaurin.

[Progress in the research of amorphous pharmaceuticals]

Yao Xue Xue Bao. 2009 May; 44(5): 443-8Ying J, Lü Y, Du GHAmorphous is a special physical state of solid compounds that the positions of the molecules or atoms have no long-range order. Sometimes amorphous compounds have better bioavailability, or achieve ultra-fast absorption in situation of acute and intermittent symptoms than that of morphous compounds, thus change drug efficacy. Besides, different pharmaceutical preparing methods can lead to different characters. Research of amorphous compounds has been a hotspot, both in research field and industry world. However, there are challenges as amorphous compounds could be unstable; unexpected adverse drug reactions may also exist. In this review, recent progress in the research of amorphous pharmaceutical compounds both in the research field and the pharmaceutical industry is reviewed. Factors which can influence the efficacy of amorphous pharmaceuticals are summarized. The prospect of amorphous techniques is also discussed.

A novel and effective multistage classification system for microscopic starch grain images.

Microsc Res Tech. 2009 Jul 20; Choy SK, Tong CS, Zhao ZZThis article presents a novel and effective multistage system for classifying Chinese Materia Medica microscopic starch grain images. The proposed classification system is constructed based on the Gaussian mixture model-based clustering, the feature assignment algorithm, and the similarity measurement. Several features for each starch grain image are extracted and every class of drug is represented by a set of characteristic features. For each stage of the system, only one feature is chosen and assigned to that stage via the feature assignment algorithm, and the corresponding characteristic features are subdivided into smaller subsets based on clustering techniques. At the final stage, each subset contains a certain class of drugs (with corresponding characteristic features) and similarity measurement is carried out for starch grain classification. Three sets of the current state-of-the-art starch grain features including the granulometric size distribution, the chord length distribution, and the wavelet signature are used to construct the system. Experimental results on a database of 240 images of 24 classes of drugs reveal the superior performance of the multistage system. Comparison with the traditional starch grain classification approaches indicates that our proposed multistage method produces a marked improvement in classification performance. Microsc. Res. Tech. 2009. (c) 2009 Wiley-Liss, Inc.

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