Table 1.

Characteristics of microtubule binding agents

Agent	Sensitivity to ABC efflux pumps	Sensitivity to β-tubulin content	references
Vincas	MDR sensitive MRP sensitive	Sensitive to βIII-tubulin content	44,189–191
Cryptophycins	MDR insensitive	n.a.	192,193
Dolastatins	MDR sensitive	n.a.	194
Taxanes	MDR sensitive MRP2 and MRP7 sensitive	Sensitive to βIII-tubulin content	45,46
Epothilones	MDR sensitive	No	103,195
Discodermolides	MDR sensitive MRP1 sensitive	Sensitive to βIII-tubulin content	196,197
Cyclostreptin	MDR insensitive	n.a.	172
Laulimalides	MDR insensitive	n.a.	198
Taccalonolide	MDR insensitive	More active if high beta III content	170
Peloruside	MDR insensitive	n.a.	169
Hemiasterlin	MDR insensitive	n.a.	168
Combretastatins	MDR insensitive	Yes	199–201
2 methoxyestradiol	MDR insensitive	Inactive against beta I	125,202

MDR: multidrug resistance; ABC: ATP Binding Cassette transport pumps; n.a.: not available