Table 2

Cytostatic effect of free and liposome-formulated compounds

FormulationGC FreeCisplatin FreeBamet-R2Bamet-UD2
FreeHD-LiposomesLD-LiposomesFreeHD-LiposomesLD-Liposomes
COR-L231  ± 32-a 52  ± 522  ± 72-a 46  ± 861  ± 52-a 36  ± 72-a 68  ± 72-a 79  ± 42-a
COR-L23/R1  ± 32-a 25  ± 42-b 18  ± 643  ± 72-a 57  ± 42-a 30  ± 565  ± 32-a 76  ± 32-a
LS174T1  ± 32-a 51  ± 543  ± 949  ± 556  ± 956  ± 762  ± 42-a 67  ± 92-a
LS174T/R2  ± 32-a 13  ± 32-b 43  ± 72-a 54  ± 72-a 63  ± 52-a 51  ± 82-a 64  ± 92-a 74  ± 62-a
WIF-B91  ± 32-a 49  ± 531  ± 62-a 40  ± 753  ± 941  ± 854  ± 864  ± 42-a
WIF-B9/R0  ± 22-a 4  ± 42-b 34  ± 62-a 37  ± 72-a 56  ± 52-a 45  ± 62-a 52  ± 42-a 68  ± 32-a
Hepa 1-62  ± 22-a 48  ± 543  ± 754  ± 761  ± 72-a 68  ± 72-a 77  ± 82-a 87  ± 42-a
Hepa 1-6/R1  ± 32-a 26  ± 32-b 37  ± 42-a 48  ± 62-a 57  ± 52-a 64  ± 52-a 74  ± 42-a 79  ± 52-a

Comparison of cytostatic effect on wild and resistant (R) sublines of the following cell lines: lung carcinoma COR-L23, human colon adenocarcinoma LS 174T, rat hepatoma-human fibroblast hybrid WIF-B9, and mouse hepatoma Hepa 1-6. The proportion of living cells compared with non-treated plates (control conditions = 100% cell viability) was determined by the formazan test after the culture had been incubated for 72 h with one of the following compounds: cisplatin, GC, Bamet-R2, Bamet-UD2, and high density (HD) or low density (LD) liposome-encapsulated Bamet-R2 or Bamet-UD2. We used drug concentrations close to the value of the cisplatin IC50 for each wild-type cell. These were: 10 μM for COR-L23 and COR-L23/R, 30 μM for LS 174T and LS 174T/R, and 5 μM for WIF-B9, WIF-B9/R, Hepa 1-6, and Hepa 1-6/R. The cytostatic effect was calculated as the ability to reduce the number of living cells (100 − cell viability). Values are means ± S.E.M. from four different cultures carried out in triplicate.

    • ↵2-a P < 0.05 compared with cisplatin;

    • ↵2-b P < 0.05 when comparing resistant with wild-type cells.