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P P Humphrey. 2001. How it started.. https://doi.org/10.1046/0333102401021s0102

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Policy developments in regulatory approval.

Although radical changes in drug regulation are rare (e.g., the Federal Food, Drug and Cosmetic Act of 1938 and the 1962 amendment to the Act creating an effectiveness requirement), regulations and guidance do evolve significantly in the face of new problems and accumulating experience. Recent changes have been driven by the Food and Drug Administration Modernization Act (FDAMA), user fee legislation, the International Conference on Harmonization, recent safety related drug withdrawals, and concerns about trial ethics and investigator conflict of interest. FDAMA and guidance developed in response to it has helped circumstances in which FDA would rely on a single study to support effectiveness and the circumstances in which surrogate endpoints could support approval. An ICH Document 'Choice of control group and related design issues in clinical trials' focussed attention on the ethics of placebo controls (acceptable, even if there is existing therapy, when the placebo-treated patient will suffer no irreversible injury) and the design of 'equivalence' or 'non-inferiority' trials. There has been greatly increased attention to obtaining good dose-response information and to assessing need for modifying treatment in demographic (age, gender, race) and concomitant disease (renal or hepatic function abnormalities) subgroups, and in assessing drug-drug interactions. Other important trends are increasing reliance on non-U.S. data, increasing numbers of FDA-industry meetings during drug development, and new focus on risk assessment and risk management.

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The ubiquitous and tissue specific promoters of the human SRC gene are repressed by inhibitors of histone deacetylases.

Histone deacetylase inhibitors have generated keen interest as potential chemopreventive and chemotherapeutic agents due to their ability to induce cell cycle arrest, differentiation, and apoptosis in a diverse group of cancer derived cell lines. Activation of the 60 kDa non-receptor tyrosine kinase, c-Src, has been a consistent finding in many tumors and tumor derived cell lines, and has been implicated in these same cellular processes. We have shown that the histone deacetylase inhibitors, sodium butyrate and Trichostatin A, repressed c-Src mRNA and protein expression in a dose-dependent manner in cell lines derived from cancers of the colon, breast and liver. Our group has previously identified two distinct promoters that are responsible for SRC transcription, separated by a distance of approximately 1 kb. Sodium butyrate and Trichostatin A strongly inhibited activity of each of these highly disparate SRC promoters, demonstrating histone deacetylase inhibitors directly repress SRC transcription. This repression did not require protein neosynthesis and was not associated with a decrease in binding of protein factors essential for either promoter's activity. Our finding that sodium butyrate and Trichostatin A inhibit both SRC promoters suggest this oncogene may be a major target of these agents, and may explain in part their anti-cancer activity.

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