Fig. 1: Elevated serine synthesis enzymes are associated with poor prognosis in lung cancer.
From: ΔNp63α drives serine synthesis to promote carboplatin resistance in NSCLC
A Serine can be either taken up from the environment or synthesized de novo through the serine synthesis pathway (SSP). The SSP consists of a three-step enzymatic process, starting with the glycolytic intermediate 3-phosphoglycerate (3-PG) which is converted to 3-phosphohydroxypyruvate (3-PP) by phosphoglycerate dehydrogenase (PHGDH). The 3-PP is then converted to 3-phosphoserine (3-PS) by phosphoserine aminotransferase 1 (PSAT1) through a glutamate-dependent transamination reaction. Finally, phosphoserine phosphatase (PSPH) catalyzes the hydrolysis of 3-PS to produce serine. Glycine is a precursor of nucleotides and amino acids. B mRNA expression levels of serine metabolism enzymes in lung cancer versus normal tissue, analyzed from the TCGA Firehose Legacy dataset on the cBioPortal platform. C Overall survival curves for lung cancer stratified by the mRNA expression levels of serine metabolism enzymes, as analyzed using the Kaplan–Meier Plotter. D mRNA expression levels of serine metabolism enzymes in LUAD and LUSC compared to normal tissue, as analyzed from the TCGA Firehose Legacy dataset on the cBioPortal platform. E Representative microphotographs showing the immunoreactivity of serine metabolism enzymes in tissue microarrays of LUAD and LUSC. F Quantitative analysis of serine metabolism enzyme expression in tissue microarrays of LUAD and LUSC. *p < 0.05; **p < 0.01; NS not significant.
