Genetically-engineered "all-in-one" vaccine platform for cancer immunotherapy

An essential step for cancer vaccination is to break the immunosuppression and elicit a tumor-specific immunity. A major hurdle against cancer therapeutic vaccination is the insufficient immune stimulation of the cancer vaccines and lack of a safe and efficient adjuvant for human use. We discovered a novel cancer immunostimulant, trichosanthin (TCS), that is a clinically used protein drug in China, and developed a well-adaptable protein-engineering method for making recombinant protein vaccines by fusion of an antigenic peptide, TCS, and a cell-penetrating peptide (CPP), termed an "all-in-one" vaccine, for transcutaneous cancer immunization. The TCS adjuvant effect on antigen presentation was investigated and the antitumor immunity of the vaccines was investigated using the different tumor models. The vaccines were prepared

Inhibition of two stages of melanin synthesis by sesamol, sesamin and sesamolin

Objective To investigate the antimelanogenesis properties of three sesame compounds-sesamol, sesamin and sesamolin via two stages of melanin synthesis vis-à-vis sunscreen function and enzyme inhibition in melanoma cell line in order to search for alternative depigmenting agents. Methods Antimelanogenic effects of sesame lignans were assessed in SK-MEL2 compared with the reference depigmenting agents, kojic acid and β-arbutin, in order to evaluate: (a) the sunscreen function of sesamol, sesamin and sesamolin by measurement of UV absorbtion property; (b) the inhibition of tyrosinase activity through mushroom and cellular tyrosinase; and (c) the effect on melanin content and melanogenic protein expression (tyrosinase, TRP-1 and TRP-2) by Western blot analysis; and (d) the toxicity of sesamol, sesamin and sesamolin to cells using cell cytotoxicity assay. Results The results showed that sesamin, sesamolin and sesamol exerted satisfiable sunscreen function by absorbed UVB at 290 nm. Sesamol exhibited the highest inhibition of mushroom tyrosinase activity, but lipophilic sesamolin exhibited the highest cellular tyrosinase inhibition (IC

Inhibition of two stages of melanin synthesis by sesamol,sesamin and sesamolin

Objective: To investigate the antimelanogenesis properties of three sesame compounds-sesamol,sesamin and sesamolin via two stages of melanin synthesis vis-`a-vis sunscreen function and enzyme inhibition in melanoma cell line in order to search for alternative depigmenting agents. Methods: Antimelanogenic effects of sesame lignans were assessed in SK-MEL2 compared with the reference depigmenting agents, kojic acid and β-arbutin, in order to evaluate:(a)the sunscreen function of sesamol,sesamin and sesamolin by measurement of UV absorbtion property; (b) the inhibition of tyrosinase activity through mushroom and cellular tyrosinase; and (c) the effect on melanin content and melanogenic protein expression(tyrosinase,TRP-1 and TRP-2)by Western blot analysis;and(d)the toxicity of sesamol,sesamin and sesamolin to cells using cell cytotoxicity assay. Results: The results showed that sesamin, sesamolin and sesamol exerted satisfiable sunscreen function by absorbed UVB at 290 nm.Sesamol exhibited the highest inhibition of mushroom tyrosinase activity, but lipophilic sesamolin exhibited the highest cellular tyrosinase inhibition (IC50of 1.6 μM) followed by sesamin, sesamol, and kojic acid, respectively.The order from high to low inhibition of melanin pigment was detected in the SK-MEL2 treated with sesamolin, sesamin, sesamol, kojic acid, and β-arbutin, respectively.Sesamolin and sesamin successfully inhibited cellular tyrosinase activity and respectively decreased TRP-1/TRP-2 (36%/15%) and TRP-1 levels (16%), thereby inhibiting melanogenesis via antityrosinase activity. No cytotoxicity to SK-MEL2 or Vero (normal) cell lines was observed at the lignan concentrations that exerted an anti-melanogenic effect. Conclusions: Three sesame lignans prevent melanin synthesis through 2 stages: (a) by blocking melanin-induction and(b)by interrupting melanogenic enzyme production.This study provides evidence that sesamol, sesamin and sesamolin are potential for anti-melanogenesis agents.

Involvement of Transglutaminase-2 in alpha-MSH-Induced Melanogenesis in SK-MEL-2 Human Melanoma Cells

Skin hyperpigmentation is one of the most common skin disorders caused by abnormal melanogenesis. The mechanism and key factors at play are not fully understood. Previous reports have indicated that cystamine (CTM) inhibits melanin synthesis, though its molecular mechanism in melanogenesis remains unclear. In the present study, we investigated the effect of CTM on melanin production using ELISA reader and the expression of proteins involved in melanogenesis by Western blotting, and examined the involvement of transglutaminase-2 (Tgase-2) in SK-MEL-2 human melanoma cells by gene silencing. In the results, CTM dose-dependently suppressed melanin production and dendrite extension in alpha-MSH-induced melanogenesis of SK-MEL-2 human melanoma cells. CTM also suppressed alpha-MSH-induced chemotactic migration as well as the expressions of melanogenesis factors TRP-1, TRP-2 and MITF in alpha-MSH-treated SK-MEL-2 cells. Meanwhile, gene silencing of Tgase-2 suppressed dendrite extension and the expressions of TRP-1 and TRP-2 in alpha-MSH-treated SK-MEL-2 cells. Overall, these findings suggested that CTM suppresses alpha-MSH-induced melanogenesis via Tgase-2 inhibition and that therefore, Tgase-2 might be a new target in hyperpigmentation disorder therapy.

Down-regulation of tyrosinase, TRP-1, TRP-2 and MITF expressions by citrus press-cakes in murine B16 F10 melanoma

Objective: To investigate the suitability of citrus-press cakes, by-products of the juice industry as a source for the whitening agents for cosmetic industry. Methods:Ethylacetate extracts of citrus-press cakes (CCE) were examined for their anti-melanogenic potentials in terms of the inhibition of melanin production and mechanisim of melanogenesis by using Western Blot analysis with tyrosinese, tyrosinase-related protein-1 (TRP-1), TRP2, and microphthalmia-associated transcription factor (MITF) proteins. To apply the topical agents, citrus-press cakes was investigated the safety in human skin cell line. Finally flavonoid analysis of CCE was also determined by HPLC analysis. Results: Results indicated that CCE were shown to down-regulate melanin content in a dose-dependent pattern. The CCE inhibited tyrosinase, TRP-2, and MITF expressions in a dose-dependent manner. To test the applicability of CCE to human skin, we used MTT assay to assess the cytotoxic effects of CCE on human keratinocyte HaCaT cells. The CCE exhibited low cytotoxicity at 50 μg/mL. Characterization of the citrus-press cakes for flavonoid contents using HPLC showed varied quantity of rutin, narirutin, and hesperidin. Conclusions:Considering the anti-melanogenic activity and human safety, CCE is considered as a potential anti-melanogenic agent and may be effective for topical application for treating hyperpigmentation disorders.

The Effect of Placental Extract on the Expression of Tyrosinase, TRP-1 and TRP-2 in SK30 Melanoma Cells / 대한피부과학회지

Placental extract is a reservoir of a large number of bioactive molecules. It has been used in skin care cosmetics and soap, it is expected to have skin whitening effect. But, the effect of placental extract on melanogenesis is not clarified yet and there are several conflicting reports. To study the effect of the placental extract on proliferation and melanogenesis of pigment cells, we examined the proliferation and change of melanin amounts and expressions of tyrosinase, tyrosinase-related protein (TRP)-1 and TRP-2 mRNA in SK30 melanoma cells, which were irradiated or not. The results were as follows: 1. The placental extract inhibited the melanogenesis of SK30 melanoma cells. 2. The placental extract showed no significant effect on the proliferation of SK30 melanoma cells. 3. The placental extract showed antimelanogenic effect by inhibiting the synthesis of tyrosinase, TRP-1 and TRP-2 mRNA. 4. The inhibitory effect of placental extract was more significant in UVB-irradiated SK30 melanoma cell lines. In conclusion, this study showed that the placental extract might be a good therapeutic regimens for UV-aggravated pigment disorders including melasma. Henceforth, further investigation is needed to identify and purify the active substance from the crude placental extract.