RESUMEN
A single case of carcinoma in situ (actinic keratosis) was treated topically with a patch consisting of an aqueous paste of a commercially available mixture (50:1) of green tea concentrate plus Capsicum (Capsol-T®) for approximately 14 days. The carcinoma responded by the formation of apoptotic blisters whereas surrounding normal tissue showed no response. A second untreated carcinoma 17 cm distant from the treated area also responded indicative of a systemic action of the substance.
Asunto(s)
Camellia sinensis , Capsicum , Carcinoma in Situ/tratamiento farmacológico , Carcinoma de Células Escamosas/tratamiento farmacológico , Queratosis Actínica/tratamiento farmacológico , Fitoterapia , Neoplasias Cutáneas/tratamiento farmacológico , Administración Tópica , Anciano , Antineoplásicos Fitogénicos/farmacología , Antineoplásicos Fitogénicos/uso terapéutico , Apoptosis/efectos de los fármacos , Humanos , Masculino , Extractos Vegetales/farmacología , Extractos Vegetales/uso terapéuticoRESUMEN
Phospholipase D (PLD) is a highly regulated enzyme involved in lipid-mediated signal transduction processes affecting vesicular trafficking and cytoskeletal reorganization. It is regulated by protein kinase C, adenosine diphosphate (ADP)-ribosylation factors and Rho family proteins, and both protein kinase C and Rho family proteins have been implicated in the metastatic potential of melanoma. We analysed PLD in four human melanoma cell lines and in primary human melanocytes. Melanoma cell lines showed phosphatidylcholine-hydrolysing, phosphatidylinositol 4,5-bisphosphate-dependent PLD activity, which was activated by phorbol ester and a non-hydrolysable guanosine triphosphate (GTP) analogue in a dose-dependent and synergistic manner, whereas primary melanocytes exhibited only low PLD activity compared with the melanoma cell lines. As determined by reverse transcription polymerase chain reaction, both splicing variants of PLD1, PLD1a and PLD1b, and the isoenzyme PLD2, are expressed in melanoma cells and melanocytes. Western blot analysis showed that PLD1 expression was low in primary melanocytes in contrast to melanoma cells, which is in agreement with our finding of low activity. Interestingly, Rho protein mRNA was elevated in all melanoma cell lines. We conclude that in human melanoma cells, the PLD activity that is stimulated by phorbol ester requires ADP-ribosylation factor, protein kinase C and Rho proteins for full activity, and most probably represents the isoenzyme PLD1.