Cytotoxicity of demalonyl thyrsiflorin A, a semisynthetic labdane-derived diterpenoid, to melanoma cells.

Diterpenes are compounds with complex structure and due to their unique carbon skeleton and interesting biological activities, have been the focus of continuous studies for the development of new anticancer agents. The plants of the genus Calceolaria (Scrophulariaceae family), native of South America have also yielded several new diterpenes with the scopadulane skeleton, such as thyrsiflorin A. The present study was undertaken to investigate the effect of the semisynthetic compound, demalonyl thyrsiflorin A on human melanoma cells. In A375 cells compound demalonyl thyrsiflorin A showed a clear dose-response relationship in the range of 6.25-50µM concentrations. In addition, we demonstrated an apoptotic response after treatment of cancer cells with this semisynthetic phenolic labdane diterpene at 6.25 and 12.5µM concentrations that probably involves the reduction of Hsp70 expression and reactive oxygen species production. Alternatively, the inhibition of the caspase cascade at higher concentrations, 25 and 50µM, correlated with additional reactive oxygen species increase, probably switched the mode of demalonyl thyrsiflorin A-induced cell death from apoptosis to necrosis.

Potential anticancer activity of lichen secondary metabolite physodic acid.

Secondary metabolites present in lichens, which comprise aliphatic, cycloaliphatic, aromatic and terpenic compounds, are unique with respect to those of higher plants and show interesting biological and pharmacological activities. However, only a few of these compounds, have been assessed for their effectiveness against various in vitro cancer models. In the present study, we investigated the cytotoxicity of three lichen secondary metabolites (atranorin, gyrophoric acid and physodic acid) on A375 melanoma cancer cell line. The tested compounds arise from different lichen species collected in different areas of Continental and Antarctic Chile. The obtained results confirm the major efficiency of depsidones. In fact, depsides atranorin and gyrophoric acid, showed a lower activity inhibiting the melanoma cancer cells only at more high concentrations. Whereas the depsidone physodic acid, showed a dose-response relationship in the range of 6.25-50 µM concentrations in A375 cells, activating an apoptotic process, that probably involves the reduction of Hsp70 expression. Although the molecular mechanism, by which apoptosis is induced by physodic acid remains unclear, and of course further studies are needed, the results here reported confirm the promising biological properties of depsidone compounds, and may offer a further impulse to the development of analogues with more powerful efficiency against melanoma cells.

Effect of vicanicin and protolichesterinic acid on human prostate cancer cells: role of Hsp70 protein.

With the aim of identifying novel agents with antigrowth and pro-apoptotic activity on prostate cancer cells, in the present study, we evaluated the effect of five lichen secondary metabolites the depsides atranorin (1), diffrattaic (2) and divaricatic (3) acids, the depsidone vicanicin (4) and the protolichesterinic acid (5) on cell growth in androgen-sensitive (LNCaP) and androgen-insensitive (DU-145) human prostate cancer cells. The cell viability was measured using MTT assay. LDH release, a marker of membrane breakdown, was also measured. For the detection of apoptosis, the evaluation of DNA fragmentation (COMET assay) and caspase-3 activity assay were employed. The expression of Bcl-2, Bax, TRAIL, COX-2, NOS2 and Hsp70 proteins was detected by western blot analysis. Generation of reactive oxygen species was measured by using a fluorescent probe. It was observed that atranorin (1), diffrattaic (2) and divaricatic (3) acids showed a lower activity inhibiting the prostate cancer cells only at more high concentrations (25 and 50µM). Whereas compounds vicanicin (4) and protolichesterinic acid (5) showed a dose-response relationship in the range of 6.25-50µM concentrations in DU-145 and LNCaP cells, activating an apoptotic process. The novel finding, in the present study, is that apoptosis induced by these compounds appears to be mediated, at least in part, via the inhibition of Hsp70 expression, that may be correlated with a modulation of redox-sensitive mechanisms. The combination of vicanicin (4) and protolichesterinic acid (5) with other anti-prostate cancer therapies could be considered a promising strategy that warrants further in vivo evaluation.

Pro-apoptotic activity of ergosterol peroxide and (22E)-ergosta-7,22-dien-5alpha-hydroxy-3,6-dione in human prostate cancer cells.

With the aim of identifying novel agents with antigrowth and pro-apoptotic activity on prostate cancer cells, we assayed the effect of ergosterol peroxide and (22E)-ergosta-7,22-dien-5alpha-hydroxy-3,6-dione, a semisynthetic compound, against androgen-sensitive (LNCaP) and androgen-insensitive (DU-145) human prostate cancer cells. Our results indicate that after 72h of incubation, ergosterol peroxide and (22E)-ergosta-7,22-dien-5alpha-hydroxy-3,6-dione at micromolar concentrations exhibited an inhibitory effect on LNCaP and DU-145 cell growth (MTT assay), but the semisynthetic compound was the most active. In addition, our results indicate that apoptotic cell demise is induced in LNCaP and DU-145 cells. In fact, a significant increase of caspase-3 activity, not correlated to LDH release, marker of membrane breakdown, was observed in both cell lines treated with ergosterol peroxide and the semisynthetic compound. With respect to genomic DNA damage, determined by COMET and TUNEL assays, the results obtained show a significant increase in DNA fragmentation when compared with the untreated control. In conclusion, the results obtained in this study, demonstrating that ergosterol peroxide and (22E)-ergosta-7,22-dien-5alpha-hydroxy-3,6-dione attenuate the growth of prostate cells, at least in part, triggering an apoptotic process, permit to confirm the use of mushrooms as origin of compounds to be used as novel therapeutic agents for prostate cancer treatment, or as models for molecules more active and selective.

Lichen metabolites prevent UV light and nitric oxide-mediated plasmid DNA damage and induce apoptosis in human melanoma cells.

In humans both UV-A and UV-B can cause gene mutations and suppress immunity, which leads to skin cancer, including melanoma. Inhibition of reactive oxygen species (ROS) and reactive nitrogen species (RNS) appears particularly promising as ROS and RNS production by both UV-A and UV-B contributes to inflammation, immunosuppression, gene mutation and carcinogenesis. We evaluated the effect of two lichen compounds, sphaerophorin (depside) and pannarin (depsidone) on pBR322 DNA cleavage induced by hydroxyl radicals (()OH), and by nitric oxide (NO), and their superoxide anion (O(2)(-)) scavenging capacity. In addition, we investigated the growth inhibitory activity of these compounds against human melanoma cells (M14 cell line). Sphaerophorin and pannarin showed a protective effect on plasmid DNA and exhibited a superoxide dismutase like effect. The data obtained in cell culture show that these lichen metabolites inhibit the growth of melanoma cells, inducing an apoptotic cell death, demonstrated by the fragmentation of genomic DNA (COMET and TUNEL Assays) and by a significant increase of caspase-3 activity, and correlated, at least in part, to the increase of ROS generation, These results confirm the promising biological properties of sphaerophorin and pannarin and encourage further investigations on their molecular mechanisms.

Demalonyl thyrsiflorin A, a semisynthetic labdane-derived diterpenoid, induces apoptosis and necrosis in human epithelial cancer cells.

In a previous study, we isolated thyrsiflorin A, a new diterpene with the scopadulane skeleton, from Calceolaria thyrsiflora (Scrophulariaceae family). Experimental evidences on the semisynthetic analogues of scopadulane diterpenes have permitted to hypothesize that a polar substituent is important for the antitumor activity of this class of compounds. Therefore, the present study was undertaken to investigate the effect of the semisynthetic compound, demalonyl thyrsiflorin A, on cell growth and death in two human epithelial cell lines, DU-145 cells (androgen-insensitive prostate cancer cells) and KB cells (oral squamous carcinoma cells). The results obtained, show that our compound, exhibited comparable degrees of antigrowth effect on cancer cells examined as judged by IC(50) values, 9.77 microM (2.73 microg/ml) and 10.86 microM (3.04 microg/ml) in DU-145 and KB cells, respectively, and support the hypothesis that also for diterpenoid compounds an available hydroxyl group is important for decreased cancer cell viability. In addition, we demonstrated an apoptotic response after treatment of DU-145 and KB cells with this semisynthetic compound at 6-12 microM concentrations, together with a necrosis process at higher doses (25-50 microM). Both apoptotic and necrotic pathway implicated in demalonyl thyrsiflorin A-treated cells are correlated with the elevation of ROS generation.

Diterpenoids from Calceolaria alba.

Chemical examination of the petrol ether (60-80) extract of the aerial parts of Calceolaria alba R. et Pav., collected in Santa Juana, VIII Region, Chile, resulted in the isolation of 3 new diterpenoids. Their structures have been elucidated by a study of their physical and spectral data; in particular using 2 NMR spectroscopy (DEPT, 1H-1H, COSY, NOESY, HMQC and HMBC).

Putrescine-1,4-dicinnamide from Pholiota spumosa (Basidiomycetes) inhibits cell growth of human prostate cancer cells.

Previously, it was isolated from the fruiting bodies of the gilled mushroom Pholiota spumosa (Basidiomycetes, Strophariaceae), putrescine-1,4-dicinnamide, a phenylpropanoid derivative conjugated with polyamine putrescine never isolated before as a natural compound. Recently, polyamine analogs that are similar in structure to the natural polyamines but that cannot mimic their functions that are essential for cellular growth and differentiation, have shown antitumor activity in several types of human cancer cells. Therefore, we have now investigated the response of DU-145 cells, a well characterized androgen-independent human prostate cancer (PCA) cell line, to this phenylpropanoid derivative. The results presented here demonstrate that putrescine-1,4-dicinnamide, as suggested for polyamine analogs synthesized artificially, inhibits the cell growth of cancer cells inducing apoptosis cell death, mediated, at least in part, by the activation of caspase cascades, that at higher doses shift to necrosis, through the increase of reactive oxygen species (ROS) generation.

What's in the pipeline about bladder reconstructive surgery? Some remarks on the state of the art.

The fusion of engineering with cell biology and advances in biomaterials may lead to de novo construction of implantable organs. Engineering of neobladder from autologous urothelial and smooth muscle cells cultured on biocompatible, either synthetic or naturally-derived substrates, is now feasible in preclinical studies and may have clinical applicability in the near future. The development of a bioartificial bladder would warrant the prevention of both the metabolic and neoplastic shortcomings of the intestinal neobladder. Two tissue-engineering techniques for bladder reconstruction have been tested on animals: 1) the in vivo technique involves the use of naturally-derived biomaterials for functional native bladder regeneration 2) the in vitro technique involves the establishment of autologous urothelial and smooth muscle cell culture from the host's urinary tract, after which the cells are seeded on the biodegradable matrix-scaffold to create a composite graft that is implanted into the same host for complete histotectonic regeneration. Waiting for the creation of a complete tissue-engineered bladder with a trigone-shaped base, we suggest, in surgical oncology after radical cystectomy, the realization of conduit or continent pouch using tissue-engineered material.

Prostatic duct carcinoma with combined prostatic duct adenocarcinoma and urothelial carcinoma features: report of a case.

We report a unique case of prostatic duct carcinoma (PDC) featuring both prostatic duct adenocarcinoma (PDA) and high-grade urothelial carcinoma (HG-UC). An 84-year-old man presenting with hematuria showed at ultrasonography and cystoscopy a papillary neoplasia located near to the verumontanum. Histopathologic examination of specimens from transurethral resection revealed a tumor originating from large prostatic ducts showing 2 different components: PDA with endometrioid features (main pattern) and HG-UC (minor part). Immunohistochemically, the areas of PDA were positive for prostatic acid phosphatase (PAP), prostatic specific antigen (PSA), and androgen receptors (AR), while negative for estrogen (ER) and progesterone receptors (PGR). Prognostic factors evaluation pointed out a low proliferation index (10%) and focal expression of p53 (6%); c-erb-B2 was not overexpressed. The HG-UC areas were negative for all previous markers, while positive for thromobomodulin. The proliferation index was high (60%), and p53 was diffusely expressed (55%). The incidence and significance of PDC with combined features is discussed with reference to literature data.

Cytotoxic activity of the root extract from Myoschilos oblongum.

The crude methanolic root extract of Myoschilos oblongum exhibited a significant cytotoxic activity against PZ-HPV-7 human prostate cells. Furthermore, two esters of docosanol were isolated from the CH(2)Cl(2) extract.

[Study of antitetanus immunity in a population sample]. / Studio della immunità antitetanica in un campione di popolazione.

A statical investigation conducted by the authors in a random population demonstrated the utility of the determination of antitetanic antibodies by means of Tetan test in order to establish the immunological defence level against infection.