Recent studies evaluating the pathogenic and predictive role of AGEs in cancer

Investigation of AGEsInvolvement of AGEs in cancersReferences
In patient samples (cancer/control)
Analysis of genetically modified circulating levels of AGEs in 1,051 patients with breast cancer by ELISA

  • Higher levels of AGEs and AGEs/sRAGE-ratio—correlated with increased breast cancer risk

  • sRAGE levels—negative correlation with breast cancer risk

  • AGEs—positive correlation with bad cancer prognosis

[41]
Analysis of plasma AGEs in 1,378 patients with primary colorectal cancer by ultra-performance liquid chromatography-tandem mass spectrometry

  • Higher ratio of MG-derived AGEs versus those derived from glyoxal displayed a strong positive correlation with colorectal cancer risk

  • CML, CEL and MG-H1—inverse correlation with colorectal cancer risk

[23]
Analysis of dietary AGEs intake in 450,111 participants by European Prospective Investigation into Cancer and Nutrition (EPIC) study

  • CML and MG-H1—inverse correlation with colorectal cancer risk, but not for CEL

  • AGEs analysed in this study may not be colorectal cancer-promotive

[42]
Analysis of dietary AGEs intake—prospective observational study by Women’s Health Initiative (WHI, WHI-USA) in 2,073 women with invasive breast cancer

  • After a median 15.1 years of follow-up, 642 deaths were registered, including 198 breast cancer specific and 129 cardio-vascular specific deaths

  • Higher consumption of dietary AGEs (CML-AGEs) after cancer diagnosis in post-menopausal women—correlated with enhanced risk of mortality from cancer as well as cardio-vascular diseases

[43]
Analysis of dietary AGEs intake—Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial in cancer-free healthy women

  • After a median 11.5 years of follow-up, 1,592 women were diagnosed with breast cancer in the PLCO

  • Highest CML-AGE intake—related to increased breast cancer risk (in situ and hormone receptor positive breast cancer) and mortality risk in healthy women

  • Increased CML-AGE intake post-diagnosis coupled with lower intake of fruits and vegetables—associated with increased mortality rate in both hormone receptor positive and negative breast cancers

[44]
Analysis of plasma AGEs—a 5-year follow-up cohort study by Shaanxi Provincial People’s Hospital, in 131 patients with stage II and III breast cancer, surgically treated

  • Incidence of metastasis significantly associated with serum AGE concentrations in the patients

  • For the period of follow-up, metastasis interval was shorter in diabetic than non-diabetic subjects

[45]
Analysis of plasma AGEs in peripheral blood mononuclear cells (PBMCs) from 20 adult survivors of paediatric Hodgkin’s lymphoma (HL)

  • Plasma AGEs (CML and MG-H1)—significantly higher in HL survivors than healthy subjects

  • Higher levels of RAGE, NADPH oxidase, oxidative stress, NF-κB and IL-6 expression, along with weakened anti-oxidant defence

  • Co-existence of AGEs, oxidative and inflammatory stress in HL survivors

  • Potentially detrimental in initiating long-term complications in HL survivors

[46]
Analysis of MG AGEs/adducts in blood-derived cultures (BDCs, liquid biopsy) of patients with cancer (18 localized and 20 advanced cases)

  • Relatively higher levels of MG glycated adducts reported in tumour tissues than the normal counterparts

  • Higher MG adducts (MGAs) in advanced cancers than the ones in localized phase

[26]
Analysis of cutaneous AGEs by skin auto-fluorescence (SAF) in type-2 diabetic patients

  • SAF is indicative of pentosidine, an AGE prevalent in skin biopsies

  • SAF values > 2.6 projected a 2.6 fold increased risk of cancer with significant association between AGEs and cancer incidence

  • Diabetic patients who had cancer or went onto develop new cancers had considerably higher initial SAF values than those who did not have or develop cancer

[47]
Analysis of histone-glycation adducts in SKBR3 breast cancer cells in vitro, MCF7 and CAMA-1 tumor xenografts in vivo and tumour samples from patients with metastasis or recurrence

  • Histones are basally glycated in breast cancer

  • Histone glycation disrupts chromatin architecture, nucleosome assembly and stability

  • Breast cancer cells, xenografts, as well as patients’ tumours showed high basal histone glycation levels and deglycase enzyme (DJ-1) overexpression

  • Link between metabolic perturbation and epigenetic dysregulation in cancer

[48]
In animal (mice) models—in vivo
Analysis of impact of dietary AGEs in pubertal FVB/n mice (model of breast cancer), fed a high AGE diet

  • High AGE-rich dietary consumption, especially in pubertal age, elicit breast cancer risk via substantial dysregulation in normal growth of mammary glands and promotion of hyperplastic lesions by adulthood

  • AGEs leave a “metabolic imprint” in the normal mammary gland micro-milieu, with potential risk for breast cancer development

[37]
Analysis of impact of dietary AGEs in wild type FVB/n and RAGE null (RAGE–/–) mice, fed persistent high AGE diet (chronic dietary-AGE model of breast cancer)

  • By influencing cellular matrix, AGEs perturb developmental programs during puberty and induce breast cancer growth

  • AGE driven changes in tissue architecture and cell function led to 3-fold rise in neoplastic growth

  • Both RAGE-dependent and independent mechanisms were involved in eliciting the same

  • Dietary AGE activated RAGE-stimulated stroma resulting in pre-neoplastic lesions, continuing into adulthood

[38]
Analysis of impact of dietary AGEs in FVB-RAGE+/+ and FVB-RAGE–/– xenograft mice (prostate cancer model), fed AGE-rich diet

  • AGE treatment prompted RAGE dimerization in activated fibroblasts

  • AGEs elicited RAGE-mediated sustenance and augmentation of migratory capacity of cancer cells

  • RAGE depletion in tumour stroma blocked AGE-driven cancer expansion

[39]
In cancer cells—in vitro
Analysis of glycation in MCF-7 cells by mass spectrometry

  • Revealed 17 glycated sites, majority in arginine residues and functional domains

[49]
Analysis of proteins in liver cancer cells by mass spectrometry

  • Fructosamine-3-kinase (FN3K) sensitive glycation of 110 proteins—transcription factors, splicing factors, histones, DNA- and RNA-binding proteins, HSPs; HSP90AA1, HSP90AA4, translation factors (eIF4A1, eIF1, eIF3G), transcription factors (NRF-2), replication and repair proteins (HELB, MCM3), splicing factors (SRSF7, PUF60) and more importantly, enzymes involved in glucose metabolism (LDHA, LDHC), were identified

[17]

ELISA: enzyme-linked immunosorbent assay; eIF4A1: eukaryotic initiation factor 4A-1; NRF-2: nuclear factor erythroid 2-related factor 2; HELB: DNA helicase B; MCM3: minichromosome maintenance complex component 3; SRSF7: serine/arginine-rich splicing factor 7; PUF60: Poly(U)-binding-splicing factor; LDHA: lactate dehydrogenase A; LDHC: lactate dehydrogenase C; IL-6: interleukin-6