Alzheimer's disease (AD) characteristically presents with early memory loss. Regulation of K ؉ channels, calcium homeostasis, and protein kinase C (PKC) activation are molecular events that have been implicated during associative memory which are also altered or defective in AD. PKC is also involved in the processing of the amyloid precursor protein (APP), a central element in AD pathophysiology. In previous studies, we demonstrated that benzolactam (BL), a novel PKC activator, reversed K ؉ channels defects and enhanced secretion of APP␣ in AD cells. In this study we present data showing that another PKC activator, bryostatin 1, at subnanomolar concentrations dramatically enhances the secretion of the ␣-secretase product sAPP␣ in fibroblasts from AD patients. We also show that BL significantly increased the amount of sAPP␣ and reduced A␤40 in the brains of APP[V717I] transgenic mice. In a more recently developed AD double-transgenic mouse, bryostatin was effective in reducing both brain A␤40 and A␤42. In addition, bryostatin ameliorated the rate of premature death and improved behavioral outcomes. Collectively, these data corroborate PKC and its activation as a potentially important means of ameliorating AD pathophysiology and perhaps cognitive impairment, thus offering a promising target for drug development. Because bryostatin 1 is devoid of tumor-promoting activity and is undergoing numerous clinical studies for cancer treatment in humans, it might be readily tested in patients as a potential therapeutic agent for Alzheimer's disease.

The lymphatic system is the primary pathway of metastasis for most human cancers. Recent research efforts in studying lymphangiogenesis have suggested the existence of a relationship between lymphatic vessel density and patient survival. However, current methodology of lymphangiogenesis quantification is still characterised by high intra-and interobserver variability. For the amount of lymphatic vessels in a tumour to be a clinically useful parameter, a reliable quantification technique needs to be developed. With this consensus report, we therefore would like to initiate discussion on the standardisation of the immunohistochemical method for lymphangiogenesis assessment. Metastasis is the leading cause of cancer mortality. Metastatic cancer cells can escape from their site of origin and spread to distant organs through invasion of the vascular system and/or the lymphatic system. Tumour vascularisation is widely accepted as a bona fide indicator of tumour growth, metastases and patient survival. In 1996, Peter Vermeulen et al (1996) published a first international consensus on the methodology and criteria of the evaluation of angiogenesis quantification in solid tumours and 5 years later, a second consensus report, in which new concepts and mechanisms of tumour vascularisation were integrated, appeared (Vermeulen et al, 2002). Both reports were aimed at improving the standardisation of angiogenesis quantification in order to allow intratumourous microvessel density to be applied as a prognostic indicator and, moreover, as a reliable predictor of the risk of malignant transformation of premalignant lesions and of response to cancer treatment. Contrary to angiogenesis, the de novo formation of lymphatic vessels or lymphangiogenesis and its role in promoting the metastatic spread of tumour cells has only recently become a focal point of cancer research with an increasing number of studies showing a relationship between patient survival and lymphatic density in different tumour types. In order to confirm the potential prognostic value of lymphangiogenesis in patients with cancer, a quantification method that is characterised by a low intra-and interobserver variability needs to be developed. In this first consensus report, we would like to provide an overview of current concepts of the lymphatic vasculature and its regulating factors and propose guidelines for the estimation of the ongoing lymphangiogenesis in solid human tumour sections.