POTENTIAL rhizome extract quantified Boesenbergia pandurata (Roxb.) Schlecht. AS AGENT FOR SKIN cancer chemoprevention
ABSTRACT: Boesenbergia pandurata extract has been known have cytotoxic effect, anti-proliferative, apoptotic induction, antioxidant, anti-inflammatory, anti-aging activity. These showed that the extract potential as an agent chemoprevention to protect UVB-induced skin damage including skin cancer. This research was carried out to examine anti-cancer effect in cancer cells-line and the protective effect of B. pandurata extract against UVB-induced oxidative stress, inflammation, immune suppression, DNA damage, which evaluated Cu,Zn-SOD, COX-2, IL-10, IL-12, CPDs expression and tumorigenesis in Balb/C mice model Boesenbergia pandurata rhizomes was collected from Bandarharjo Kalibawang Kulon Progo, Daerah Istimewa Yogyakarta. The rhizomes were extracted by maceration method using 90% ethanol. The extract was quantified with pinostrobin as active marker using TLC scanner. In vitro assays used HeLa cells-line and Vero cells-line as control. The cytotoxic and anti-proliferative assays used MTT method and apoptotic induce by double staining method using ethidium bromide and acridine orange. Experimental animals in vivo assays were Balb/c mice 4 weeks old, which devided into 6 groups: normal control (untreated), negative control (drinking water + UVB), vehicle (solvent of extract +UVB), and 3 group with orally administration B. pandurata extract was dose 20, 40, and 60 mg/kg BW/day and UVB. The extract was given orally at 14 days before UV exposure (1395 mJ/cm2) until termination of the experiment. Back hair of mice was shaved before UV-B exposure. Expression of Cu,Zn-SOD, COX-2, IL-10, IL-12, and CPDs were observation at 0, 2, 24, 48, and 72 after UVB exposure. At each time point (2, 24, 48, and 72h after UV exposure) three mice from each group were sacrificed, dorsal skin of mice were necropsied. The skin samples (3x3cm2) were fixed with 10% buffered formalin and embedded in paraffin. Tissue sections were stained by imunohistochemical method then analyze by image analyzer software (ImageJ). The tumorigenesis assay used chronic UVB exposure (465 mJ/m2/day) were 60 time exposure (5 times per week), experimental animals was observation on onset of tumor, incidence and multiplicity. Results of the study demonstrated of B. pandurata extract contain 0.49% pinostrobin. The extract demonstrated activity of cytotoxic (IC50 56µg/mL), antiproliferative, and apoptotic induce on HeLa cancer cells-line. The in vivo assay showed that the extract had chemoprevention effect with optimum dose was 60mg/kg BW/day. It could significantly decrease COX-2 expression was 43%, IL-10 (43 %), CPDs (84%), and increasing IL-12 fivefold from vehicle group, while it did not show a significantly effect on Cu, Zn-SOD expression. The protective effect of B. pandurata extract on UVB-induced carcinogenesis was showed to increase of survival time was 2,2 month, decrease incidence was 40% and multiplicity of tumor was 60%. The result can be concluded that B. pandurata extract (contain 0,49% pinostrobin) has chemoprevention activity on UVBinduced skin tumorigenesis through anti-inflammatory capabilities, recovery immune system, and protect the DNA damage.
