LDHA, which catalyzes oxidation of pyruvate to lactate, is downregulated in mutIDH1R132H glioma cells, PDX (mouse), and PTBs,213,217,218 whereas LDHB (which converts lactate to pyruvate) has increased expression in mutIDH1R132H-expressing BT142 cells, PTBs, and PDX (mouse) gliomas.104. The gene discussed is LDHB; the disease is central nervous system cancer.