Compound 5 Structure hLDHA IC ± µM hLDHB IC ± 0.07 µM Supplementary Figure S1

Supplementary Figure S2 Compound % inhibition  M 30  M 60  M 120  M B A concentration in cell,  M Cmpd 1Cmpd 2Cmpd 3 NADHCmpd IC50 67 nM 43 nM 22 nM 12 nM

13 C 15 N- Arg/Lys HEK293 SILAC Mix 1:1 Ratio SNU C 14 N- Arg/Lys Protein Concentration Prepare lysates triplicate Protein Concentration recomb LDHA Spike 13 C 15 N- Arg/Lys HEK293 SILAC Supplementary Figure S3 Trypsin digest LC-MS/MS Trypsin digest LC-MS/MS B A Snu398 HepG2 LDHA copies/cell LDHA cell concentration 4.7 x x C Hek x MM Relative Intensity % rLDHA HEK293 Relative Intensity % HEK293Snu398 LLIVSNPVDILTYVAWK

LDHA LDHB A CD Snu398MDA-MB-453MiaPaCa-2NCI-H1395Snu423U251A2780Cal-27HepG2786-O LDHA,  M  -actin Supplementary Figure S4 7=042 LDHA 234 trxn 2, days trxn 1, days WB LDHAsi 7 E HepG2KidneyMelanomaLiverColonPancreasBreast LDHA  -actin LDHB LDHA,  M B

Supplementary Figure S5

FBP, nmol/mln cells DMSOCmpd 1Cmpd 2 Supplementary Figure S6 FBP, nmol/mln cells < 0.3 DMSOCmpd 1Cmpd 2 A B

Supplementary Figure S7

relative pathway activity HepG2Snu398 pentose phosphate glycolysis fatty acid synthesis glutaminolysis Supplementary Figure S8 A B