Background The induced differentiation of tumor cells represents a very important strategy in modern antineoplastic therapy. Retinoids are the most frequently used group of cell differentiation inducers; however, their toxicity and intrinsic or acquired resistance to retinoids substantially limit their use in clinical protocols. Therefore, special attention has been paid to the combined treatme...

Vitamin A, its physiological metabolites and synthetic derivatives (retinoids) have been shown to have protective effects against the development of certain types of cancer. In addition, pharmacological amounts of retinoids have been used with some success in the treatment of a few human tumors. The chemoprevention effect of retinoids is most likely exerted at the tumor promotion phase of carci...

Chemoprevention by retinoids of the progression of carcinomas induced in rats by azaserine was evaluated. Wistar/Lewis rats were given 15 weekly injections of azaserine, 10 mg/kg, while fed a chow diet; after the completion of carcinogen treatment, they were fed a chow diet supplemented with four different retinoids at the level of 0.5 to 2 mmol/kg diet for 1 year. The incidence of neoplasms wa...

Retinoids were studied both to identify what skeletal components are important in the modulation of normal and leukemic human myeloid clonal proliferation and differentiation in vitro and to elucidate the mechanism by which retinoids modulate proliferation of hematopoietic cells. Retinoids with a derivatized terminal carboxyl group were significantly less active than all-trans-retinoic acid, an...

The effect of retinoids on breast cancer has been predominantly studied in vitro, on established cell lines, which in biology differ significantly from primary tumor cells. Little is known on whether early in vitro passages of breast cancer cells (EPBCCs) are differentially sensitive to retinoids and differentially express retinoid acid receptors (RARs) and retinoid X receptors (RXRs). We have ...

Retinoids modulate the growth and differentiation of cancer cells presumably by activating gene transcription via the nuclear retinoic acid receptor (RAR) alpha, beta, and gamma and retinoid X receptor (RXR) alpha, beta, and gamma. We analyzed the effects of 38 RAR-selective and RXR-selective retinoids on the proliferation of 10 human head and neck squamous cell carcinoma (HNSCC) cell lines. Al...

Vitamin A and its derivatives, the retinoids, have been implicated as important signaling molecules in vertebrate development, primarily due to numerous gain-of-function experiments involving treatment of embryos with exogenous retinoic acid. Collectively, the results from these experiments suggested that retinoids were sufficient to mimic the action of endogenous factors which posteriorize the...