Accelerated cellular senescence phenotype of GAPDH-depleted human lung carcinoma cells

Abstract

Glyceraldehyde 3-phosphate dehydrogenase (GAPDH) is a pivotal glycolytic enzyme, and a signaling molecule which acts at the interface between stress factors and the cellular apoptotic machinery. Earlier, we found that knockdown of GAPDH in human carcinoma cell lines resulted in cell proliferation arrest and chemoresistance to S phase-specific cytotoxic agents. To elucidate the mechanism by which GAPDH depletion arrests cell proliferation, we examined the effect of GAPDH knockdown on human carcinoma cells A549. Our results show that GAPDH-depleted cells establish senescence phenotype, as revealed by proliferation arrest, changes in morphology, SA-β-galactosidase staining, and more than 2-fold up-regulation of senescence-associated genes DEC1 and GLB1. Accelerated senescence following GAPDH depletion results from compromised glycolysis and energy crisis leading to the sustained AMPK activation via phosphorylation of α subunit at Thr172. Our findings demonstrate that GAPDH depletion switches human tumor cells to senescent phenotype via AMPK network, in the absence of DNA damage. Rescue experiments using metabolic and genetic models confirmed that GAPDH has important regulatory functions linking the energy metabolism and the cell cycle networks. Induction of senescence in LKB1-deficient non-small cell lung cancer cells via GAPDH depletion suggests a novel strategy to control tumor cell proliferation.

The Expression of Glyceraldehyde-3-Phosphate Dehydrogenase Associated Cell Cycle (GACC) Genes Correlates with Cancer Stage and Poor Survival in Patients with Solid Tumors

“…This result is in agreement with recent studies demonstrating that GAPDH depletion switches human tumor cells to a senescent phenotype [34]. Rescue experiments that employed metabolic and genetic models confirmed that GAPDH has important regulatory functions that link energy metabolism and cell cycle networks.…”

Cytotoxicity of chemotherapeutic agents in glyceraldehyde-3-phosphate dehydrogenase-depleted human lung carcinoma A549 cells with the accelerated senescence phenotype

“…Earlier, we demonstrated that inhibition of glycolysis by knockdown of GAPDH led to the accelerated senescence phenotype in A549 cells through sustained activation of AMP-activated protein kinase and accumulation of p53 [5]. This phenotype was acquired in the absence of DNA damage or telomere shortening [5].…”

“…RNAi with short duplex RNA RNA interference (RNAi) experiments were performed using predesigned Stealth RNA (GAPDH Validated Stealth RNAi DuoPak duplexes 1 and 2; Invitrogen, Carlsbad, California, USA), as described earlier [5]. Transient transfection was performed in T25 flasks, with cells plated at a density of 1.4 Â 10 4 cells/cm 2 by electroporation using a Neon Transfection System as per the manufacturer's protocol (Invitrogen).…”

“…Earlier, we demonstrated that the energy metabolism crisis induced by knockdown of glyceraldehyde-3-phosphate dehydrogenase (GAPDH) results in sustained activation of AMP-activated protein kinase, activation of the p53-p21 axis, and cell proliferation arrest due to senescence in human carcinoma cells [5,6]. GAPDH occupies the central position in the glycolytic pathway, thus playing a critical role in the energy metabolism of cancer cells.…”

In silico structural and phylogenetic analysis of glyceraldehyde 3-phosphate dehydrogenase (GAPDH) in domestic animals

“…Glyceraldehyde 3-phosphate dehydrogenase (GAPDH) is one of the important glycolytic enzyme which has tremendous role not only in carbohydrate metabolism but also in transcriptional activation, apoptosis initiation, ER to Golgi vesicle shuttling, and axoplasmic transport (Tarze et al, 2007).Due to its glycolytic and anti apoptopic effect, this enzyme is over expresed and positively correlated in progression of various tumors in human as well as in animals (Ramos et al, 2015). Moreover GAPDH enzyme is used as a novel therapeutic target to control the tumoregenosis by exploiting the protective power towards the telomere shortening (Phadke et al, 2011). It has been shown that several neurodegenerative diseases in animals are linked to the interaction of GAPDH with other proteins (Allen et al, 2012).…”