Oxamic acid (CAS 471-47-6), also known as aminooxoacetic acid or oxalic acid monoamide, is a simple amino acid derivative with the chemical formula C₂H₃NO₃. As an amino-substituted derivative of glyoxylic acid, oxamic acid holds significant value in biochemical and pharmaceutical research, particularly recognized as an inhibitor of lactate dehydrogenase (LDH).
Oxamic acid is a specific inhibitor of lactate dehydrogenase (LDH), particularly the LDH-A isoform. Its mechanism involves competitive inhibition of the LDH active site, blocking the conversion of pyruvate to lactate, thereby interfering with cellular glycolytic metabolism. This intervention in tumor cell energy metabolism makes it an important tool compound in cancer metabolism research.
Oxamic acid, as an LDH-A inhibitor, is widely used in studies of tumor metabolic reprogramming. Research has shown that oxamic acid inhibits proliferation, migration, and invasion of ovarian cancer A2780 and SKOV3 cells. In nasopharyngeal carcinoma CNE-1 and CNE-2 cells, oxamic acid inhibits cell proliferation in a dose- and time-dependent manner, induces G2/M phase cell cycle arrest, and promotes apoptosis through caspase-3 activation and mitochondrial pathways.
Oxamic acid and its derivatives are used to study selective inhibition of LDH isoenzymes. Studies have found that N-substituted oxamic acid derivatives exhibit selective inhibition against mouse LDHx, with DL-N-secbutyl oxamate showing 31-fold higher affinity for LDHx than LDH-5, and 36-fold higher than LDH-1.
Oxamic acid enhances the antitumor effect of PARP inhibitors in BRCA mutation-negative ovarian cancer cells. When combined with radiotherapy, sodium oxamate (750 mg/kg, intraperitoneal injection) improves in vivo tumor inhibition efficacy.
Oxamic acid serves as an organic ligand for preparing functionalized metal oxide nanoparticles for various biological applications. Together with p-aminobenzoic acid, oxamic acid is used to functionalize gold nanoparticles for developing colorimetric sensors for Fe³⁺ ion detection.
| Parameter | Typical Condition |
| Detection Wavelength | 340 nm (NADH) |
| Buffer Systems | Tris-HCl or Phosphate, pH 7.0–8.0 |
| Temperature | 25°C or 37°C |
| Assay Format | UV-Vis or microplate kinetic assay |
Detection conditions depend entirely on the enzyme-coupled system used.
Specific inhibition of lactate dehydrogenase (LDH) activity
Enables straightforward measurement of enzyme kinetics
Cost-effective tool for metabolic and glycolysis studies
Well-documented in LDH inhibition and metabolic research literature
