Glyoxalase 1 sustains the metastatic phenotype of prostate cancer cells via EMT control

Abstract

Metastasis is the primary cause of death in prostate cancer (PCa) patients. Effective therapeutic intervention in metastatic PCa is undermined by our poor understanding of its molecular aetiology. Defining the mechanisms underlying PCa metastasis may lead to insights into how to decrease morbidity and mortality in this disease. Glyoxalase 1 (Glo1) is the detoxification enzyme of methylglyoxal (MG), a potent precursor of advanced glycation end products (AGEs). Hydroimidazolone (MG‐H1) and argpyrimidine (AP) are AGEs originating from MG‐mediated post‐translational modification of proteins at arginine residues. AP is involved in the control of epithelial to mesenchymal transition (EMT), a crucial determinant of cancer metastasis and invasion, whose regulation mechanisms in malignant cells are still emerging. Here, we uncover a novel mechanism linking Glo1 to the maintenance of the metastatic phenotype of PCa cells by controlling EMT by engaging the tumour suppressor miR‐101, MG‐H1‐AP and TGF‐β1/Smad signalling. Moreover, circulating levels of Glo1, miR‐101, MG‐H1‐AP and TGF‐β1 in patients with metastatic compared with non‐metastatic PCa support our in vitro results, demonstrating their clinical relevance. We suggest that Glo1, together with miR‐101, might be potential therapeutic targets for metastatic PCa, possibly by metformin administration.

Testosterone and Follicle Stimulating Hormone–Dependent Glyoxalase 1 Up-Regulation Sustains the Viability of Porcine Sertoli Cells through the Control of Hydroimidazolone– and Argpyrimidine-Mediated NF-κB Pathway

“…28,29 Gene Silencing Glo1 silencing was performed as previously described. 23,27 Briefly, cells were transiently transfected with a pool of four siRNA oligonucleotides targeting Glo1 (ON-TARGET plus SMART pool siRNA) or with a pool of nontargeting siRNA oligonucleotides (siCtr) (ON-TARGET plus siCONTROL) to exclude off-target effects (all from Dharmacon RNA Technologies, Carlo Erba, Milan, Italy), using DharmaFECT 2 transfection reagent (Dharmacon RNA Technologies, Carlo Erba, Milan, Italy), according to the manufacturer's instructions and as previously described. 25,47 Knockdown of Glo1 was verified biochemically (protein and enzymatic activity) and at the molecular level (transcript) by Western blotting and spectrophotometric assay, or RT-qPCR, respectively.…”

“…25,47 Knockdown of Glo1 was verified biochemically (protein and enzymatic activity) and at the molecular level (transcript) by Western blotting and spectrophotometric assay, or RT-qPCR, respectively. 23 Mock transfection was performed to control for nonspecific effects of the transfection reagent. Because siCtr-or mock-treated and nontransfected cells were indistinguishable in the assays of biological phenomena examined here (data not shown), the observed changes were shown with respect only to siCtr-exposed cells.…”

“…Immunodetection of MG-H1 and ArgPyr, AGEs generated from the spontaneous modification of arginine residues by MG, the substrate of Glo1, 23 was performed in total protein extracts from SCs unexposed (control) or exposed to T and FSH. These hormones, singly or in combination, induced a significant decrease in MG-H1 ( Figure 2) and ArgPyr ( Figure 2) intracellular levels compared with untreated cells.…”

MiR‐129‐5p promotes docetaxel resistance in prostate cancer by down‐regulating CAMK2N1 expression

“…Resistance can be formed through a variety of mechanisms, both intrinsic and extrinsic, but the details remain largely unknown. 5 Among various miRNAs, miR-129 has been shown to play a key role in tumourigenesis, tumour progression, chemotherapy resistance and cell proliferation. 4 Recently, studies have shown that miRNAs are frequently misregulated in many types of human cancers.…”

“…For instance, some may act as potent oncogene promoting tumour growth and migration but demoting apoptosis, while others may act as tumour suppressor genes by targeting downstream genes to inhibit migration and invasion of tumour cells. 5 Among various miRNAs, miR-129 has been shown to play a key role in tumourigenesis, tumour progression, chemotherapy resistance and cell proliferation. 6 For instance, miR-129 was initially confirmed to be decreased in undifferentiated gastric cancer tissue, colorectal, gastric and liver cancer.…”