A. Falcone et al., SYNERGISTIC ANTIPROLIFERATIVE ACTIVITY OF SURAMIN AND INTERFERON-ALPHA-2A AGAINST HUMAN COLORECTAL ADENOCARCINOMA CELL-LINES - IN-VITRO STUDIES, European journal of cancer, 30A(4), 1994, pp. 516-520
Suramin, a polysulphonated naphthylurea proven to be an effective anti
cancer agent against selected tumours, and alpha 2A-interferon (alpha
2A-IFN) were investigated for their combined effects on HCT-8, HCT-15,
CL-D, SW-480 and SW-620 human colorectal adenocarcinoma cell lines. A
ll lines were sensitive to clinically achievable concentrations of sur
amin in a dose-dependent manner, while alpha 2A-IFN alone induced only
a modest reduction of cell growth. Concomitant treatment with suramin
and alpha 2A-IFN resulted in a synergistic inhibition of cell viabili
ty in each cell line at all doses tested. However, when suramin and al
pha 2A-IFN were administered sequentially, inhibition of cell viabilit
y was clearly dependent on the timing of treatment schedule, with maxi
mum effect obtained when alpha 2A-IFN was administered prior to surami
n. In contrast, pretreatment with suramin was markedly inferior to the
former one. In conclusion, suramin and alpha 2A-IFN exert a synergist
ic effect on human colorectal cell proliferation in vitro at clinicall
y achievable concentrations. This observation may have clinical releva
nce although the mechanisms of interaction remain to be elucidated.