Lichens produce various unique chemicals that can be used for pharmaceutical purposes. To screen for novel lichen secondary metabolites showing inhibitory activity against lung cancer cell motility, we tested acetone extracts of 13 lichen samples collected in Chile. Physciosporin, isolated from Pseudocyphellaria coriacea (Hook f. & Taylor) D.J. Galloway & P. James, was identified as an effective compound and showed significant inhibitory activity in migration and invasion assays against human lung cancer cells. Physciosporin treatment reduced both protein and mRNA levels of N-cadherin with concomitant decreases in the levels of epithelial-mesenchymal transition markers such as snail and twist. Physciosporin also suppressed KITENIN (KAI1 C-terminal interacting tetraspanin)-mediated AP-1 activity in both the absence and presence of epidermal growth factor stimulation. Quantitative real-time PCR analysis showed that the expression of the metastasis suppressor gene, KAI1, was increased while that of the metastasis enhancer gene, KITENIN, was dramatically decreased by physciosporin. Particularly, the activity of 3’-untranslated region of KITENIN was decreased by physciosporin. Moreover, Cdc42 and Rac1 activities were decreased by physciosporin. These results demonstrated that the lichen secondary metabolite, physciosporin, inhibits lung cancer cell motility through novel mechanisms of action. With the aim of screening new anti-cancer agents that inhibit cancer cell motility, we tested the inhibitory activity of seven lichen species collected from the Romanian Carpathian Mountains against migration and invasion of human lung cancer cells and further investigated the molecular mechanisms underlying their anti-metastatic activity. Among them, Alectoria samentosa, Flavocetraria nivalis, Alectoria ochroleuca, and Usnea florida showed significant inhibitory activity against motility of human lung cancer cells. HPLC results showed that usnic acid is the main compound in these lichens, and (+)-usnic acid showed similar inhibitory activity that crude extract have. Mechanistically, -catenin-mediated TOPFLASH activity and KITENIN-mediated AP-1 activity were decreased by (+)-usnic acid treatment in a dose-dependent manner. The quantitative real-time PCR data showed that (+)-usnic acid decreased the mRNA level of CD44, CyclinD1 and c-myc, which are the downstream target genes of both -catenin/LEF and c-jun/AP-1. Also, Rac1 and RhoA activities were decreased by treatment with (+)-usnic acid. Interestingly, higher inhibitory activity for cell invasion was observed when cells were treated with (+)-usnic acid and cetuximab. These results implied that (+)-usnic acid might have potential activity in inhibition of cancer cell metastasis, and (+)-usnic acid could be used for anti-cancer therapy with a distinct mechanisms of action. Endolichenic fungi are microbes inhabited in the thalli of lichens. In this study, endolichenic fungi was used for screen their anti-cancer activity. Acetone extract of EL002332, isolated from Endocarpon pusillum collected from China desert in 2010, showed selective cytotoxicity on AGS, human gastric cancer cell, and CT26, mouse colon cancer cell. Pure compound myC was separated from the mycelium acetone extract from liquid large culture system and showed much more potent cytotoxicity than crude extracts in MTT assay on AGS cell line. Especially, myC greatly increased the apoptotic cell population around IC50 concentration and activated apoptotic signaling by regulating Bcl-2 family protein expression and caspase pathway activity. In addition, both EL002332 crude extracts and myC decreased AGS cell motility at sub-lethal concentration. In vivo xenograft experiment showed that sizes of tumor were significantly smaller in EL002332 crude extract treated group. However, pure compound myC showed no effect on in vivo xenograft experiment probably because of the solubility. In addition, combined treatment of EL002332 crude extracts and docetaxel showed synergistic effect on both AGS and TMK1 cell lines. Taken together, our results revealed that an endolichenic fungus EL002332 has potential anti-cancer activity on human gastric cancer cell. Usnic acid (UA), a well-known lichen secondary substance, has been found have significant inhibitory activity on colon cancer cell invasion ability. In order to explore the clinical usage for usnic acid, potassium usnate (KU) was acquired as described (Martins, Silva et al. 2014). Obviously, the concentration of KU in plasma was found around 10 fold (1.69±0.122μΜ) higher than that of UA (0.181±0.016μΜ) by LC-MS/MS detection after 30mg/kg (125μΜ) oral administration in CT26 induced mouse xenograft model. While only potassium could be detected as high as 0.0302±0.033μΜ in isolated tumor tissue. KU inhibited colon cancer cell invasion assay through EMT mediated signaling pathway. Additionally, tumor growth in mouse liver metastasis model was found decreased by KU dramatically from 100ug/mouse i.p. injection. Moreover，KU also revealed cytotoxicity to cetuximab resistant colon cancer cells. Together, our results suggest a potential clinical use of KU in anti-cancer therapy.