Preliminary Observation on the Clinical Tolerance of Interferon-Beta in Cancer Patients

A phase I study of human natural interferon-beta in cancer patients

In this phase I study 15 patients with metastatic tumors were given interferon (IFN)-beta by i.v. bolus injections. Twelve individual doses of 1, 2, 3.3, 5, 7, 9, 12, 16, 21, 27, 35, and 46 x 10(6) IU were administered every other day. The single maximal tolerated dose ranged from 9 to 46 x 10(6) IU. Eight patients tolerated the dose of 46 x 10(6) IU without side effects. Disturbances of cardiac rhythm were observed, but were closely related temporally to severe chills and appeared to be the consequence of adrenergic stimulation associated with this side-effect. In addition, no significant variations in the left ventricular function as assessed by nuclear stethoscope were observed. Neurotoxicity was not a major side-effect. The toxicity of IFN-beta given as scheduled in this study was significant, but acceptable.

Effect of natural beta-interferon on cell proliferation and steroid receptor level in human breast cancer cells

The effect of natural beta-interferon (beta-IFN) on cell proliferation and steroid receptor level was investigated in CG-5 human breast cancer cell line. beta-interferon determines an appreciable diminution of cell growth, at concentrations ranging from 100 to 1000 IU/ml, which is enhanced when serum content of the culture medium is lowered. Low concentrations of beta-IFN (10-100 IU/ml) produce, after a 5-day treatment, an increase in estrogen receptors (ER) and progesterone receptors (PR). No variation of ER and PR levels is observed when beta-IFN is added directly to the cell homogenate before the assay. Our data suggest that beta-IFN could affect hormone sensitivity through a modification of ER and PR in neoplastic mammary cells.