To date many kinds of compounds have been obtained from plants kingdom as antineoplastic and anti-cancerous agents. However, there is no special type of compounds for cancer therapy. Various types of substances are effective for various types of cancers and tumors: for instance, alkaloids. lignans, terpenes and steroids etc. Curcumol obtained from Curcuma aromatica was tested and noticed to be effective against cancer of the uterine cervix clinically. Oridonin isolated from Rabdosia ssp. is now investigate for clinical trials in China. Moreover camptothecine isolated from Camptotheca acuminata is also antineoplastic alkaloid, but is very toxic. Chemical modification has been tried to decrease its toxicity This compound is now using as clinical agent. Harringtonin was investigated as an anticancerous drug in China. Taxol, a compound with a taxane ring isolated from the bark of Taxus brevifotia. has been demonstrated to have substantial anticancer activity in patients with solid tumors refractory standard chemotherapy. Supply of this drug has severely limited full exploration of its antineoplastic potential Some efforts are continued in National Cancer Institute(NCI) Washington for surveying various Taxus species for optimal taxol content, improvement in semi-synthesis from baccatin 111, improvement in method of extraction, and development of alternative renewable resources. Further, there are many compounds which have been reported as antineoplastic agents. On the other hand, we have screened on higher plants collected In Japan, China, Korea. Southeast Asia and South America for antineoplastic activity, which has been done using Sarcoma 180 ascites in mice, P388 Iymphocytic leukemia In mice, Chinese hamster lung V-79 cells, P388 cells and nasopharynx carcinoma(KB) cells in our laboratory, as primary screening. In this meeting, 1 will present on antitumor and cytotoxic substances of the higher plants(Rubis cordifolia, Ailanthus vilmoriniana, Aster tataricus, Taxus cuspidata var. nana, Cephalotaxus harringtonia var. drupacea, etc.) selected from above screening tests.

Many plants collected at Japan, China, Korea, Imdonesia and South America were applied to antitumor and / or cytotoxic screening tests against Sarcoma 180 ascites in mice and / or V-79, KB, P388 cultured cells. On the course of these screening tests, alcoholic extracts of Forsythia viridissima (Oleaceae), Eurycoma longifolia(Simaroubaceae), Rubia cordifolia and R. akane(Rubiaceae), Cissampelos pareira and Abuta concolor (Menispermaceae), Nardostachys chinensis (Valerianacese), Mansoa alliaceae (Bignoniaceae), Casearia sylvestris (Flacourtiacear), Maytenus ilicifolia (Celastraceae), Hedychium coronarium (Zingiberaceae), Croton palanostigma(Euphorbiaceae), Cocculus trilobus(Menispermaceae), Ginkgo biloba(Ginkgoaceae), Alpinia galanga and Cucculus zanthorrhiza(Zingiberaceae), Evodia rutaecarpa(Rutaceae), and Periploca sepium(Asclepiadaceae) showed significant activity and their active principles were clarified. In this paper, a few antitumor substances in above plants are introduced.