Plant derived products are widely used in cancer treatment. Gall species has been preferred for treatment various diseases in folk medicine, but there are few studies on the anticancer effects of gall species. The present study reports the antioxidant activity and total secondary metabolites of extracts ofA. tomentosusgalls. The antioxidant potency of galls was carried out using differentin-vitromodel systems. Their cytotoxic efficacy on Mia-Paca cell line was also explored. Gall extract was found to contain a large amount of phenolic acids. The extract potently scavenged free radicals including DPPH (IC(50)9.56 +/- 1.08 mu g/mL), ABTS (IC(50)18.51 +/- 0.25 mu g/mL). It can be seen as a potential source of antioxidants according to beta-carotene/linoleic acid method (%92.58 +/- 0.92) and Phosphomolybdenum assays (104.36 +/- 4.95 mgAE/g). Gall extract also posses ability of metal chelating (%40.07 +/- 2.30) and Fe3+(184.01 +/- 2.83 mgTE/g) and Cu2+(89.81 +/- 0.96 mgTE/g) reducing activity. According to total secondary metabolites tests, gall extract showed high total phenolic, total flavonoid and total tannin amount. HPLC analysis of the extract suggested it to contain caffeic acid (424.068.479 mu g/g), ellagic acid (187.696.132 mu g/g). XTT assay revealed gall extract to enhance percent survival of Mia-Paca2 cell line exposedA. tomentosusextracts. The best cytotoxic effect was determined in acetone extracts (IC50: 124.7 mu M). Expression of some genes (Bax, Bcl-2, FAS, BID, caspase-3, caspase-8, caspase-9, caspase-10, FADD, TRADD) in the apoptosis pathway was determined to invastigate apoptosis inducing activity. These results indicate thatA. tomentosusgalls possess potent antioxidant activity, when tested both in chemical as well as biological models. C1 [Kilincarslan Aksoy, Ozge] Pamukkale Univ, Dept Biol, Sci & Art Fac, Denizli, Turkey. [Mammadov, Ramazan] Mugla Sitki Kocman Univ, Dept Mol Biol Genet, Mugla, Turkey. [Secme, Mucahit] TurkeyPamukkale Univ, Med Fac, Dept Med Biol, Denizli, Turkey.