CA9 Silencing Promotes Mitochondrial Biogenesis, Increases Putrescine Toxicity and Decreases Cell Motility to Suppress ccRCC Progression

Abstract

Carbonic anhydrase IX (CA9), a pH-regulating transmembrane protein, is highly expressed in solid tumors, and particularly in clear cell renal cell carcinoma (ccRCC). The catalytic mechanisms of CA9 are well defined, but its roles in mediating cell migration/invasion and survival in ccRCC remain to be determined. Here, we confirmed that the mRNA expression of CA9 in ccRCC was significantly higher than that in para-carcinoma tissues from analysis of the datasets in The Cancer Genome Atlas. CA9 knockdown upregulated oxidative phosphorylation-associated proteins and increased mitochondrial biogenesis, resulting in the reversal of the Warburg phenotype and the inhibition of cell growth. Our study revealed that CA9 knockdown upregulated mitochondrial arginase 2 (ARG2), leading to the accumulation of putrescine, which suppressed ccRCC proliferation. Surfaceomics analysis revealed that CA9 knockdown downregulated proteins associated with extracellular matrix (ECM)–receptor interaction and cell adhesion, resulting in decreased cell migration. CA9 silencing also downregulated amino acid transporters, leading to reduced cellular amino acids. Collectively, our data show that CA9 knockdown suppresses proliferation via metabolic reprogramming and reduced cell migration, reaffirming that CA9 is a potential therapeutic target for ccRCC treatment.

Duodenal Metabolic Profile Changes in Heat-Stressed Broilers

“…Although IPA predicted an activation of CA9 in CHS (z score of 2) and HDAC11 in PF (z score of 2), real-time quantitative PCR showed that these genes were downregulated by both heat stress conditions, indicating a potential feedback loop. Both CA9 and HDAC11 have been shown to be involved in mitochondrial function and many anomalies including stress, hypoxia and alkalosis [ 147 , 148 , 149 , 150 ], all of which are associated with heat stress [ 31 , 151 , 152 ]. In support of IPA-network prediction, molecular analyses demonstrated that CHS affected the duodenal expression of MAPK1 , MAPK14 , MAPK9 , SOD1 , and SOD2 genes.…”

Intracellular pH differentially regulates transcription of metabolic and signaling pathways in normal epithelial cells

“…Upregulation of CA9 is associated with increased proliferation and migration behaviors that are associated with increased pHi (Chiche et al ., 2009; Benej et al ., 2020). CA9 silencing, on the other hand, suppresses proliferation, promotes mitochondrial biogenesis, and reduces cell migration all behaviors associated with decreased pHi (Cianchi et al ., 2010; Csaderova et al ., 2013; Xu et al ., 2020). Our RNASeq data suggests that pHi-dependent regulation of CA9 expression may reinforce these pH-dependent processes.…”

Nicotinamide N-Methyltransferase Remodeled Cell Metabolism and Aggravated Proinflammatory Responses by Activating STAT3/IL1β/PGE2 Pathway

“…A wound healing assay was performed according to the method described in our previous study . Briefly, monolayer cells with 95% confluence were wounded by scratching the surface of each well in a 6-well plate as uniformly as possible with a 200 μL pipet tip.…”

“…A wound healing assay was performed according to the method described in our previous study. 23 Briefly, monolayer cells with 95% confluence were wounded by scratching the surface of each well in a 6-well plate as uniformly as possible with a 200 μL pipet tip. The wells were then rinsed with PBS three times, and the well was replenished with 1640 medium without FBS, incubated at 37 °C for 72 h. Images of the initial wound, and the movement of cells into the scratched area, were captured using a Nikon microscope (Olympus Corporation, Tokyo, Japan) at 0 and 72 h. This assay was done in triplicates.…”