Tigilanol tiglate is an oncolytic small molecule that induces immunogenic cell death and enhances the response of both target and non-injected tumors to immune checkpoint blockade.

Background: Tigilanol tiglate (TT) is a protein kinase C (PKC)/C1 domain activator currently being developed as an intralesional agent for the treatment of various (sub)cutaneous malignancies. Previous work has shown that intratumoral (I.T.

Activation of PKC supports the anticancer activity of tigilanol tiglate and related epoxytiglianes.

The long-standing perception of Protein Kinase C (PKC) as a family of oncoproteins has increasingly been challenged by evidence that some PKC isoforms may act as tumor suppressors. To explore the hypothesis that activation, rather than inhibition, of these isoforms is critical for anticancer activity, we isolated and characterized a family of 16 novel phorboids closely-related to tigilanol tiglate (EBC-46), a PKC-activating epoxytigliane showing promising clinical safety and efficacy for intratumoral treatment of cancers. While alkyl branching features of the C12-ester influenced potency, the 6,7-epoxide structural motif and position was critical to PKC activation in vitro.

An improved preparation of phorbol from croton oil.

Croton oil is the only commercial source of the diterpenoid phorbol (), the starting material for the semi-synthesis of various diesters extensively used in biomedical research to investigate cell function and to evaluate in vivo anti-inflammatory activity. While efficient chemoselective esterification protocols have been developed for phorbol, its isolation from croton oil is technically complicated, and involves extensive manipulation of very toxic materials like the oil or its native diterpenoid fraction. The preparation of a crude non-irritant phorboid mixture from croton oil was telescoped to only five operational steps, and phorbol could then be purified by gravity column chromatography and crystallization.

The reaction of cinnamaldehyde and cinnam(o)yl derivatives with thiols.

Spurred by the alleged relevance of the thia-Michael reaction in the bioactivity of various classes of cinnam(o)yl natural products and by the development of a quick NMR assay to study this reaction, we have carried out a systematic study of the "native" reactivity of these compounds with dodecanethiol and cysteamine as models, respectively, of simple thiols and reactive protein thiols that can benefit from iminium ion catalysis in Michael reactions. Cinnamoyl esters and amides, as well as cinnamyl ketones and oximes, did not show any reactivity with the two probe thiols, while cinnamaldehyde () reacted with cysteamine to afford a mixture of a thiazoline derivative and compounds of multiple addition, and with aliphatic thiols to give a single bis-dithioacetal (). Chalchones and their vinylogous C5-curcuminoid derivatives were the only cinnamoyl derivatives that gave a thia-Michael reaction.

Determination of free and glucosidically-bound volatiles in plants. Two case studies: L-menthol in peppermint (Mentha x piperita L.) and eugenol in clove (Syzygium aromaticum (L.) Merr. & L.M.Perry).

This study arises from both the today's trend towards exploiting plant resources exhaustively, and the wide quantitative discrepancy between the amounts of commercially-valuable markers in aromatic plants and those recovered from the related essential oil. The study addresses the determination of both the qualitative composition and the exhaustive distribution of free and glucosidically-bound L-menthol in peppermint aerial parts (Mentha x piperita L., Lamiaceae) and of eugenol in dried cloves (Syzygium aromaticum (L.

A cannabigerol quinone alleviates neuroinflammation in a chronic model of multiple sclerosis.

Phytocannabinoids like ∆(9)-tetrahydrocannabinol (THC) and cannabidiol (CBD) show a beneficial effect on neuroinflammatory and neurodegenerative processes through cell membrane cannabinoid receptor (CBr)-dependent and -independent mechanisms. Natural and synthetic cannabinoids also target the nuclear receptor peroxisome proliferator-activated receptor-gamma (PPARγ), an attractive molecular target for the treatment of neuroinflammation. As part of a study on the SAR of phytocannabinoids, we have investigated the effect of the oxidation modification in the resorcinol moiety of cannabigerol (CBG) on CB(1), CB(2) and PPARγ binding affinities, identifying cannabigerol quinone (VCE-003) as a potent anti-inflammatory agent.

Synthesis and biological evaluation of 12-aminoacylphorboids.

Spurred by the paradoxical anti-inflammatory activity of some aminoacylphorbol derivatives, the naturally occurring and epimeric N,N-dimethylvalinoyl-4alpha-4-deoxyphorbol derivatives 3b and 3d have been prepared from 4alpha-4-deoxyphorbol (3e), a byproduct of the isolation of phorbol from Croton oil and a phorboid polyol so far largely overlooked in terms of biological activity. The configuration of the side chain stereocenter was confirmed for both natural products, and to investigate the side chain structure-activity relationships within this class of compounds, their corresponding N,N-dimethylglycinate (3g) and nor (3h) and di-nor derivatives (3i, 3j) were also prepared. By using a PKC-sensitive model of HIV-1 latency (activation of HIV- gene expression in Jurkat-LAT-GFP cells), it was found that both 3b and 3d can activate PKC-dependent responses, while a series of experiments with isoform-specific PKC inhibitors showed that these compounds target PKCalpha and -delta.

Modulation of the transient receptor potential vanilloid channel TRPV4 by 4alpha-phorbol esters: a structure-activity study.

The mechanism of activation of the transient receptor potential vanilloid 4 (TRPV4) channel by 4alpha-phorbol esters was investigated by combining information from chemical modification of 4alpha-phorbol-didecanoate (4alpha-PDD, 2a), site-directed mutagenesis, Ca(2+) imaging, and electrophysiology. Binding of 4alpha-phorbol esters occurs in a loop in the TM3-TM4 domain of TRPV4 that is analogous to the capsaicin binding site of TRPV1, and the ester decoration of ring C and the A,B ring junction are critical for activity. The lipophilic ester groups on ring C serve mainly as a steering element, affecting the orientation of the diterpenoid core into the ligand binding pocket, while the nature of the A,B ring junction plays an essential role in the Ca(2+)-dependence of the TRPV4 response.

Antibacterial cannabinoids from Cannabis sativa: a structure-activity study.

Marijuana (Cannabis sativa) has long been known to contain antibacterial cannabinoids, whose potential to address antibiotic resistance has not yet been investigated. All five major cannabinoids (cannabidiol (1b), cannabichromene (2), cannabigerol (3b), Delta (9)-tetrahydrocannabinol (4b), and cannabinol (5)) showed potent activity against a variety of methicillin-resistant Staphylococcus aureus (MRSA) strains of current clinical relevance. Activity was remarkably tolerant to the nature of the prenyl moiety, to its relative position compared to the n-pentyl moiety (abnormal cannabinoids), and to carboxylation of the resorcinyl moiety (pre-cannabinoids).

Differential effects of phorbol-13-monoesters on human immunodeficiency virus reactivation.

The persistence of latent reservoirs of HIV-1 represents a major barrier to virus eradication in patients treated with antiretrovirals. Prostratin is a non-tumor promoting 12-deoxyphorbol monoester capable of up-regulating viral expression from latent provirus and therefore is potentially useful for HIV adjuvant therapy and similar properties might be elicited by related non-tumor promoting phorboids. We have therefore investigated a series of phorbol 13-monoesters for their capacity to reactivate HIV latency.

alpha-fetoprotein expression in a dedifferentiated liposarcoma.

Extremely rare cases of paraneoplastic syndromes or ectopic production of proteins associated with liposarcoma are reported in literature. We describe a unique case of relapsing retroperitoneal dedifferentiated liposarcoma with biochemical, immunohistochemical, and molecular evidence of alpha-fetoprotein (AFP) ectopic production. The lesion was associated to elevated AFP plasma levels that subsided after tumor removal.

Potential applications of molecular biology in neuroendocrine tumors.

The impact of molecular biology procedures on neuroendocrine (NE) tumor biology is gradually evolving from purely academic and research studies to clinical applications. This review deals with applications of molecular techniques in neuroendocrine tumors, with special reference to their potential for diagnostic, prognostic, or therapeutic impact. Since the cloning of the genes involved in inherited endocrine tumor syndromes, molecular analysis of the responsible genetic alterations has become a routine diagnostic tool to select affected patients and their relatives, and also an interesting approach to investigate the pathogenesis of neuroendocrine tumors.

Primitive Neuroectodermal Tumor of the Meninges: An Histological, Immunohistochemical, Ultrastructural, and Cytogenetic Study.

We report a case of primitive neuroectodermal tumor (PNET) arising from the meninges in a 30-yr-old female patient whose clinical and radiological features were consistent with meningioma. The neoplasm was composed of primitive small, round cells, growing in sheets and nests in continuity with meningeal layers. Ultrastructurally, the neoplastic cells were characterized by large and regular nuclei, primitive cytoplasm with pools of glycogen, and lack of dense core granules.

Detection procedures for neuroblastoma cells metastatic to blood and bone marrow: blinded comparison of chromogranin A heminested reverse transcription polymerase chain reaction to tyrosine hydroxylase nested reverse transcription polymerase chain reaction and to anti-GD2 immunocytology.

Specific and sensitive tumor cell detection is becoming increasingly important for diagnosing and staging as well as for the therapeutic management of neuroblastoma patients. We propose a chromogranin A heminested reverse transcription polymerase chain reaction (CgA hn RT-PCR) procedure for the detection of neuroblastoma minimal residual disease in peripheral blood and bone marrow samples. The results were checked in comparison with the presently available procedures (i.