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Couroupita guianensis, a medicinal plant autochthonal to South America and South India, is widely used in the ethnomedicine of the indigenous peoples of these regions thanks to its alleged antimicrobial, anti-inflammatory, antioxidant and wound-healing properties. The majority of studies have mainly analyzed organic extracts of the Indian plant's flowers and leaves, with limited research on its bark decoction, traditionally used in Amazonian shamanic medicine. In this study, we investigated the anticancer effects of the bark decoction and its main fractions obtained through chromatographic separation, as well as the underlying molecular mechanisms in AGS gastric cancer cells. Viability, cell proliferation, cell cycle, apoptosis and protein expression related to these processes were evaluated. Both the bark decoction and fraction III significantly inhibited cell viability, and the cytotoxic effect was linked to cell cycle blockade and the induction of apoptosis also through an engulfment of the autophagic flux. Increased expression or activation of the key proteins (p53, p21, cdk2, Bak, caspases, pAMPK, pAkt, beclin, p62 and LC3BII) involved in these processes was observed. The results obtained confirmed an important anticancer effect of C. guianensis bark decoction, providing scientific validation for its use in traditional medicine and highlighting its potential as a therapeutic agent against gastric cancer. [ABSTRACT FROM AUTHOR]

Colocasia esculenta (L.) Schott is a tuberous plant, also known as taro, employed as food worldwide for its renowned nutritional properties but also traditionally used in several countries for medical purposes. In this study, methanolic extracts were prepared from the corms and leaves of Colocasia, subsequently fractionated via molecular exclusion chromatography (RP-HPLC) and their anti-tumor activity assessed in an in vitro model of gastric adenocarcinoma (AGS cells). Vorm extract and isolated fractions II and III affected AGS cell vitality in a dose-dependent manner through the modulation of key proteins involved in cell proliferation, apoptosis, and cell cycle processes, such as caspase 3, cyclin A, cdk2, IkBα, and ERK. To identify bioactive molecules responsible for anti-tumoral activity fractions II and III were further purified via RP-HPLC and characterized via nuclear magnetic resonance (NMR) and electrospray mass spectrometry (ESI-MS) techniques. The procedure enabled the identification of ten compounds including lignans and neolignans, some isolated for the first time in taro, uncommon megastigmane derivatives, and a gallic acid derivative. However, none of the isolated constituents showed efficacy equivalent to that of the fractions and total extract. This suggests that the whole Colocasia phytocomplex has intriguing anti-tumor activity against gastric cancer. [ABSTRACT FROM AUTHOR]

Abstract Background Lung cancers consist of four major types that and for clinical-pathological reasons are often divided into two broad categories: small cell lung cancer (SCLC) and non-small cell lung cancer (NSCLC). All major histological types of lung cancer are associated with smoking, although the association is stronger for SCLC and squamous cell carcinoma than adenocarcinoma. To date, epidemiological studies have identified several environmental, genetic, hormonal and viral factors associated with lung cancer risk. It has been estimated that 15-25% of human cancers may have a viral etiology. The human papillomavirus (HPV) is a proven cause of most human cervical cancers, and might have a role in other malignancies including vulva, skin, oesophagus, head and neck cancer. HPV has also been speculated to have a role in the pathogenesis of lung cancer. To validate the hypothesis of HPV involvement in small cell lung cancer pathogenesis we performed a gene expression profile of transgenic mouse model of SCLC induced by HPV-16 E6/E7 oncoproteins. Methods Gene expression profile of SCLC has been performed using Agilent whole mouse genome (4 × 44k) representing ~ 41000 genes and mouse transcripts. Samples were obtained from two HPV16-E6/E7 transgenic mouse models and from littermate's normal lung. Data analyses were performed using GeneSpring 10 and the functional classification of deregulated genes was performed using Ingenuity Pathway Analysis (Ingenuity® Systems, http://www.ingenuity.com). Results Analysis of deregulated genes induced by the expression of E6/E7 oncoproteins supports the hypothesis of a linkage between HPV infection and SCLC development. As a matter of fact, comparison of deregulated genes in our system and those in human SCLC showed that many of them are located in the Aryl Hydrocarbon Receptor Signal transduction pathway. Conclusions In this study, the global gene expression of transgenic mouse model of SCLC induced by HPV-16 E6/E7 oncoproteins led us to identification of several genes involved in SCLC tumor development. Furthermore, our study reveled that the Aryl Hydrocarbon Receptor Signaling is the primarily affected pathway by the E6/E7 oncoproteins expression and that this pathway is also deregulated in human SCLC. Our results provide the basis for the development of new therapeutic approaches against human SCLC.

Diuron [3‐(3,4‐dichlorophenyl)‐1,1‐dimethylurea] is a substituted urea herbicide, carcinogenic for the rat urinary bladder. It has been hypothesized that Diuron cytotoxicity, resulting in regenerative proliferation, leads to urothelial hyperplasia and, finally, to bladder tumors, but molecular mechanisms of carcinogenesis have not still fully investigated. Here, we report the results of a study aimed at verifying the involvement of BAG3, an intracellular protein expressed in several tumors, in the Diuron‐induced carcinogenesis. For this purpose, we analyzed the effect of Diuron on human primary urothelial cells and on human dermal fibroblasts. We found that while high concentrations of Diuron have a cytotoxic effect in human primary urothelial cells, in the same cells, noncytotoxic concentrations of the herbicide induce BAG3 expression. These findings show that BAG3 is a molecular target of Diuron and unravel the possible involvement of BAG3 protein in bladder carcinogenesis induced by the herbicide. In addition, these results suggest that BAG3 might be a potential early biomarker of damage induced by chronic exposure to Diuron. [ABSTRACT FROM AUTHOR]