Anti-angiogenic effects of epigallocatechin-3-gallate in human skin.

Epigallocatechin-3-gallate (EGCG) is the main polyphenol component of green tea. This compound exhibits antioxidant, immunomodulatory, photoprotective, anti-angiogenic, and anti-inflammatory properties. We conducted a small randomized, double blind, split face trial using a cream containing 2.5% w/w of EGCG. Four healthy volunteers with significant erythema and telangiectasia on the face applied EGCG cream to one side of the face, and vehicle control cream to the other, twice daily for six weeks. After six weeks, biopsies were taken from EGCG and vehicle treated sites. Immunohistochemistry was used to measure VEGF and HIF-1 α. HIF-1 α expression was decreased in EGCG treated sites, such that 28.4% of the epidermis showed positive staining in vehicle treated vs. 13.8% in EGCG treated sites (p<0.001). A similar decrease in VEGF expression was found (6.7% in EGCG vs. 11.0%in in vehicle-treated skin (p<0.005). EGCG topical treatments influence HIF-1 α induction and VEGF expression and may serve as a potential agent in the prevention of telangiectasias.

Silicon phthalocyanine (Pc 4) photodynamic therapy is a safe modality for cutaneous neoplasms: results of a phase 1 clinical trial.

BACKGROUND: Photodynamic therapy (PDT) is a non-invasive treatment for non-melanoma skin cancer. However, PDT systems currently used clinically have limitations such as pain and superficial tissue penetration. The silicon phthalocyanine Pc 4 is a second-generation photosensitizer with peak absorption in the far red at 675 nm. OBJECTIVE: To assess the safety and tolerability of topically applied Pc 4 followed by red light (Pc 4-PDT) in treating cutaneous neoplasms. STUDY DESIGN/MATERIALS AND METHODS: Forty three adults with a diagnosis of neoplasms including actinic keratoses, Bowen's disease, squamous cell carcinoma, basal cell carcinoma, or mycosis fungoides were treated with a single administration of Pc 4-PDT and followed for 14 days. The study utilized a light and Pc 4 dose escalation design in sequential groups of three subjects each. RESULTS: Pc 4-PDT was well tolerated with no significant local toxicity or increased photosensitivity. It has promising biologic effects, particularly in mycosis fungoides where 14 of 35 subjects demonstrated a clinical response, which correlates with Pc 4-PDT-induced apoptosis, as measured by increased active caspase-3 in the treated skin lesions. CONCLUSIONS: Pc 4-PDT is a safe and tolerable treatment modality that effectively triggers apoptosis in cutaneous neoplasms such as mycosis fungoides.

Photodynamic therapy with the silicon phthalocyanine pc 4 induces apoptosis in mycosis fungoides and sezary syndrome.

Our current focus on the effects of Photodynamic Therapy (PDT) using silicon phthalocyanine Pc 4 photosensitizer on malignant T lymphocytes arose due to preclinical observations that Jurkat cells, common surrogate for human T cell lymphoma, were more sensitive to Pc 4-PDT-induced killing than epidermoid carcinoma A431 cells. Mycosis fungoides (MF) as well as Sezary syndrome (SS) are variants of cutaneous T-cell lymphoma (CTCL) in which malignant T-cells invade the epidermis. In this study, we investigated the cytotoxicity of Pc 4-PDT in peripheral blood cells obtained from patients with SS and in skin biopsies of patients with MF. Our data suggest that Pc 4-PDT preferentially induces apoptosis of CD4(+)CD7(-) malignant T-lymphocytes in the blood relative to CD11b(+) monocytes and nonmalignant T-cells. In vivo Pc 4-PDT of MF skin also photodamages the antiapoptotic protein Bcl-2.