Synthesis and conformational analysis of some new pyrano[2, 3-c]xanthen-7-one and pyrano[3, 2-a]xanthen-6one derivatives with cytotoxic activity

The synthesis, conformational analysis and preliminary biological evaluation of some new pyrano[2, 3-c]xanthen-7-ones and pyrano[3, 2-o]xanthen6-ones is described. Certain compounds possess interesting cytotoxic activity against murine leukemia L1210 cells

Synthesis and cytotoxic activity of 2-dialkylaminoethylamino substituted xanthenone and thioxanthenone derivatives

The synthesis and biological evaluation of some new pyranoxanthenones and pyranothioxanthenones, substituted with flexible amino side-chains, and their evaluation as potential antitumor agents is described. The cytotoxic activity of the compounds and their eventual selective effect on a phase of the cell cycle were evaluated in vitro, using the murine lymphocytic L1210 leukemia cell line. The new aminoderivatives exhibited highly potent cytotoxicity against the leukemia L1210 cell line when compared to acronycine. All the compounds induced a partial accumulation of cells in the G2+M phase of the cell cycle. (C) 2000 Elsevier Science S.A

Design and synthesis of some new pyranoxanthenones with cytotoxic activity

As part of a research program directed towards the design and synthesis of pyranoxanthones structurally related to acronycine, we present here the synthesis and cytotoxic activity of the pyranoxanthones 3 and 4 (X= H, Br; R= H, OMe; R'= H, Ac). Some of these compounds inhibit L1210 cell proliferation

Clinical significance of kallikrein-related peptidase-4 in oral cancer.

Kallikrein-related-peptidase-4 (KLK4), a serine protease originally discovered in developing tooth with broad target sequence specificity, serves vital functions in dental enamel formation. KLK4 is involved in degradation of extracellular matrix proteins and it is thought that this proteolytic activity could also promote tumor invasion and metastasis. Recent studies have associated KLK4 expression with tumor progression and clinical outcome, particularly in prostate and ovarian cancers. Very little is known in regard with KLK4 involvement in oral squamous cell carcinomas (OSCCs). Our objective was to investigate KLK4 expression in OSCC pathogenesis and disease progression. KLK4 expression was evaluated by immunohistochemistry, Western blots and zymograms in OSCC lines. Invasion assays using high versus low/undetectable KLK4-expressing OSCC cell lines were performed jointly with KLK4 siRNA inhibition. A large collection of OSCC specimens was evaluated for KLK4 expression and correlation with patients’ characteristics and outcomes were determined. Our data indicates that KLK4 is differentially expressed in oral carcinomas. OSCC cell lines with high invasive and metastatic potential show the highest levels of KLK4 expression. KLK4 mRNA and protein expression is correlated with enzyme activity detected by zymograms. Inhibition of KLK4 expression results in diminished invasive potential in OSCC cell lines. Consistently, KLK4 expression is stronger in primary tumors that later either recurred or developed metastases suggesting that its preferential expression in OSCC might contribute to the individual tumor biology. Therefore, this study provides supportive evidence in favor of a prognostic value for KLK4 in OSCC and suggests that KLK4 could serve as a potential therapeutic target in oral cancer patients