1-Naphthol: a potential selective antitumour agent.

A major problem in cancer chemotherapy is the lack of selective toxicity of many commonly used anti-cancer agents towards tumour tissue compared to normal tissue.1 This is due primarily to the fact that many of these drugs, such as the alkylating agents, attack rapidly dividing tissues of the host as well as the tumour. Another area of concern is the refractory nature of many solid tumours to established drugs. In particular, colorectal cancer patients have a poor prognosis and only 5-fluorouracil is the standard single agent with a significant, although limited, benefit in advanced disease.2 In this study, Inaphthol is shown to exhibit a selectively toxic action in short-term organ cultures of human colonic tumour tissue compared to normal tissue from the same patients. In addition, this compound is cytotoxic in vitro to both cell lines and xenografts derived from human colonic turnours, Based on our studies, we suggest that l-naphthol and related derivatives may be of potential benefit in cancer chemotherapy. In short-term organ cultures, human colonic tumour tissue was markedly more sensitive than normal tissue, from the same patient, to inhibition of protein synthesis by I-naphthol (Figure 1). A half maximal inhibitory effect was evident at 0.76 mM for tumours but was not reached until 2.lmM innormaltissue. Selective toxicity towards the tumourhas been apparent in 19 out of 24 patients so far studied. The limited value of 5-fluorouracil in