Perfluorinated Compounds: Evaluation of the biological and molecular effects on cell models

L’acido perfluorottanoico (PFOA) e l’acido perfluoronanoico (PFNA) sono composti perfluorurati (PFCs) comunemente utilizzati nell’industria, negli ultimi 60 anni, per diverse applicazioni. A causa della loro resistenza alla degradazione, questi composti sono in grado di accumularsi nell’ambiente e negli organismi viventi, da cui possono essere assunti in particolare attraverso la dieta. Le esistenti evidenze sugli effetti dell’esposizione negli animali, tra cui la potenziale cancerogenicità, hanno accresciuto l’interesse sui possibili rischi per la salute nell’uomo. Recenti studi sull’uomo indicano che i PFC sono presenti nel siero, con livelli molto alti soprattutto nei lavoratori cronicamente esposti, e sono associati positivamente al cancro al seno e alla prostata. Inoltre, sono state riportate proprietà estrogen-like e variazioni nei livelli di metilazione sui promotori di alcuni geni. L’esposizione in utero è stata associata positivamente a ipometilazione globale del DNA nel siero cordonale. L’obiettivo di questo studio è stato quello di indagare gli effetti dell’esposizione a questi perfluorurati su linee cellulari tumorali e primarie umane (MOLM-13, RPMI, HEPG2, MCF7,WBC, HMEC e MCF12A), appartenenti a diversi tessuti target, utilizzando un ampio range di concentrazioni (3.12 nM - 500 μM). In particolare, si è valutato: la vitalità, il ciclo cellulare, l’espressione genica, la metilazione globale del DNA e la metilazione gene specifica. Dai risultati è emerso come entrambi i perfluorurati abbiano effetti biologici: PFOA presenta un effetto prevalente citostatico, PFNA prevalentemente citotossico. L’effetto è, però, prevalente sulle linee cellulari primarie di epitelio mammario (HMEC, MCF12A), anche a concentrazioni riscontrate in lavoratori cronicamente esposti (≥31,25 µM). Dall’analisi su queste cellule primarie, non risultano variazioni significative della metilazione globale del DNA alle concentrazioni di 15,6 e 31,25 µM. Emergono invece variazioni sui geni marcatori del cancro al seno, del ciclo cellulare, dell’apoptosi, del pathway di PPAR-α e degli estrogeni, ad una concentrazione di 31,25 µM di entrambi i PFCs.Perfluorooctanoic acid (PFOA) and perfluoronanoico acid (PFNA) are perfluorinated compounds (PFCs) largely employed during the last 60 years for several applications. Because of their resistance to degradation, they accumulate in the environment and organisms, for which the principal route of intake is the diet. The available information concerning their adverse effects on health in animals has recently increased the interest on the possible health risks in humans. Studies in humans indicate that PFCs are in serum at very high levels, especially in workers chronically exposed. Positive association with breast cancer and prostate cancer have been reported, but also estrogen -like property and variations in levels of methylation on genes promoters. In utero exposure was positively associated with global DNA hypomethylation in cord blood serum. The aim of this study was to investigate the effects of exposure to these perfluorinated on tumor and primary human cell lines ( MOLM -13, RPMI, HEPG2, MCF7, WBC, HMEC, MCF12A, belonging to different target tissues, using a wide range of concentrations (3.12 nM - 500 µM). In particular, it was assessed: the viability, cell cycle, gene expression, the global DNA methylation and gene specific methylation. The results showed that PFOA has a cytostatic effect, PFNA is mainly cytotoxic. The prevalent effect is on mammary epithelium primary cell(HMEC, MCF12A), even at concentrations found in chronically exposed workers (≥ 31.25 µM). The results don’t show significant changes in global DNA methylation at concentrations of 15.6 and 31.25 µM on the same cells, but we found variations of the methylation level on breast cancer markers genes and cell cycle, apoptosis, PPAR-α and estrogen pathways genes, after exposure to a concentration of 31.25 µM of PFCs

Early detection of gastric cancer using global, genome-wide and IRF4, ELMO1, CLIP4 and MSC DNA methylation in endoscopic biopsies

Clinically useful molecular tools to triage gastric cancer patients are not currently available. We aimed to develop a molecular tool to predict gastric cancer risk in endoscopy-driven biopsies obtained from high-risk gastric cancer clinics in low resource settings.We discovered and validated a DNA methylation biomarker panel in endoscopic samples obtained from 362 patients seen between 2004 and 2009 in three high-risk gastric cancer clinics in Lima, Perú, and validated it in 306 samples from the Cancer Genome Atlas project ( TCGA ). Global, epigenome wide and gene-specific DNA methylation analyses were used in a Phase I Biomarker Development Trial to identify a continuous biomarker panel that combines a Global DNA Methylation Index (GDMI) and promoter DNA methylation levels of IRF4, ELMO1, CLIP4 and MSC.We observed an inverse association between the GDMI and histological progression to gastric cancer, when comparing gastritis patients without metaplasia (mean = 5.74, 95% CI, 4.97-6.50), gastritis patients with metaplasia (mean = 4.81, 95% CI, 3.77-5.84), and gastric cancer cases (mean = 3.38, 95% CI, 2.82-3.94), respectively (p \u3c 0.0001). Promoter methylation of IRF4 (p \u3c 0.0001), ELMO1 (p \u3c 0.0001), CLIP4 (p \u3c 0.0001), and MSC (p \u3c 0.0001), is also associated with increasing severity from gastritis with no metaplasia to gastritis with metaplasia and gastric cancer.Our findings suggest that IRF4, ELMO1, CLIP4 and MSC promoter methylation coupled with a GDMI\u3e4 are useful molecular tools for gastric cancer risk stratification in endoscopic biopsies

Androgen receptor in breast cancer: The "5W" questions

Androgen receptor (AR) is expressed in 60-70% of breast cancers (BCs) and the availability of anti-AR compounds, currently used for treating prostate cancer, paves the way to tackle specifically AR-positive BC patients. The prognostic and predictive role of AR in BC is a matter of debate, since the results from clinical trials are not striking, probably due to both technical and biological reasons. In this review, we aimed to highlight WHAT is AR, describing its structure and functions, WHAT to test and HOW to detect AR, WHERE AR should be tested (on primary tumor or metastasis) and WHY studying this fascinating hormone receptor, exploring and debating on its prognostic and predictive role. We considered AR and its ratio with other hormone receptors, analyzing also studies including patients with ductal carcinoma in situ and with early and advanced BC, as well. We also emphasized the effects that both other hormone receptors and the newly emerging androgen-inducible non coding RNAs may have on AR function in BC pathology and the putative implementation in the clinical setting. Moreover, we pointed out the latest results by clinical trials and we speculated about the use of anti-AR therapies in BC clinical practice

ACE2 and TMPRSS2 Potential Involvement in Genetic Susceptibility to SARS-COV-2 in Cancer Patients

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a global pandemic. One open question is whether genetics could influence the severity of symptoms. Considering the limited data on cancer patients, we analyzed public data repositories limited to investigate angiotensin-converting enzyme 2 (ACE2) and the transmembrane serine protease 2 (TMPRSS2) expressions and genetic variants to identify the basis of individual susceptibility to SARS-CoV-2. Gene expression and variant data were retrieved from Tissue Cancer Genome Atlas, Genotype-Tissue Expression, and gnomAD. Differences in gene expression were tested with Mann-Whitney U-test. Allele frequencies of germline variants were explored in different ethnicities, with a special focus on ACE2 variants located in the binding site to SARS-CoV-2 spike protein. The analysis of ACE2 and TMPRSS2 expressions in healthy tissues showed a higher expression in the age class 20 to 59 years (false discovery rate [FDR] < 0.0001) regardless of gender. ACE2 and TMPRSS2 were more expressed in tumors from males than females (both FDR < 0.0001) and, opposite to the regulation in tissues from healthy individuals, more expressed in elderly patients (FDR = 0.005; FDR < 0.0001, respectively). ACE2 and TMPRSS2 expressions were higher in cancers of elderly patients compared with healthy individuals (FDR < 0.0001). Variants were present at low frequency (range 0% to 3%) and among those with the highest frequency, the variant S19P belongs to the SARS-CoV-2 spike protein binding site and it was exclusively present in Africans with a frequency of 0.2%. The mechanisms of ACE2 and TMPRSS2 regulation could be targeted for preventive and therapeutic purposes in the whole population and especially in cancer patients. Further studies are needed to show a direct correlation of ACE2 and TMPRSS2 expressions in cancer patients and the incidence of COVID-19

Why the complications of COVID-19 patients differ in elderly and young cancer patients

Zhang et al. reported the impact of different risk factors and comorbidities in COVID-19 lethality. The authors observed that the odds of dying by COVID-19 in cancer patients decrease with age and cancer becomes a non-significant factor above 80 years. We speculate on the possible causes for the different COVID-19 severity between elderly and young patients. Several factors that can have a different impact on young and elderly have to be taken into account such as inflammation, microbiota and anti-cancer therapies. Inflammaging is a complex process that characterizes elderly people and it is believed to contribute to the severity of COVID-19 associated with old age. Cancer and related therapies may alter the process of inflammaging both quantitatively and qualitatively and could impact on COVID-19 severity. Moreover, therapies used in elderly cancer patients are usually different from that used for young people where the presence of comorbidities and the mechanisms of action of the different drugs both on the susceptibility genes and on other factors have to be considered. Sex hormones and anti-estrogen therapies affect significantly gene expression in target cells thereby modulating the susceptibility of the tissues to SARS-CoV-2 infection and as a consequence the extent of the symptoms. The concentration of sex hormones varies with aging and among sexes. Interestingly, recent evidences, further corroborate the hypothesis that also sex hormones or anti-estrogen therapies impact the susceptibility to COVID-19 and its severity

Ki67 and PR in Patients Treated with CDK4/6 Inhibitors: A Real-World Experience

CDK4/6 inhibitors (CDK4/6i) are recommended in patients with estrogen receptor (ER)-positive, HER2-negative advanced breast cancer (ABC). Up to now, no prognostic biomarkers have been identified in this setting. We retrospectively analyzed the expression of progesterone receptor (PR) and Ki67, assessed by immunohistochemistry, in 71 ABC patients treated with CDK4/6i and analyzed the impact of these markers on progression-free survival (PFS). The majority of patients 63/71 (88.7%) received palbociclib, 4 (5.6%) received ribociclib, and 4 (5.6%) received abemaciclib. A higher median value of Ki67 was observed in cases undergoing second-line treatment (p= 0.047), whereas the luminal B subtype was more prevalent (p= 0.005). In the univariate analysis of the first-line setting, luminal A subtype showed a trend towards a correlation with a longer PFS (p= 0.053). A higher continuous Ki67 value led to a significantly shorter PFS. When the interaction between pathological characteristics and line of treatment was considered, luminal B subtype showed a significantly (p= 0.043) worse outcome (Hazard Ratio (HR) 2.84; 1.03-7.82 95% Confidence Interval (CI)). PFS in patients undergoing endocrine therapy plus CDK4/6i was inversely correlated with Ki67 expression but not with PR, suggesting that tumor proliferation has a greater impact on cell cycle inhibitors combined with endocrine therapy than PR expression

NMR-Based Metabolomic Approach Tracks Potential Serum Biomarkers of Disease Progression in Patients with Type 2 Diabetes Mellitus

Type 2 diabetes mellitus (T2DM) is a metabolic disorder characterized by chronic hyperglycemia associated with alterations in carbohydrate, lipid, and protein metabolism. The prognosis of T2DM patients is highly dependent on the development of complications, and therefore the identification of biomarkers of T2DM progression, with minimally invasive techniques, is a huge need. In the present study, we applied a H-1-Nuclear Magnetic Resonance (H-1-NMR)-based metabolomic approach coupled with multivariate data analysis to identify serum metabolite profiles associated with T2DM development and progression. To perform this, we compared the serum metabolome of non-diabetic subjects, treatment-naive non-complicated T2DM patients, and T2DM patients with complications in insulin monotherapy. Our analysis revealed a significant reduction of alanine, glutamine, glutamate, leucine, lysine, methionine, tyrosine, and phenylalanine in T2DM patients with respect to non-diabetic subjects. Moreover, isoleucine, leucine, lysine, tyrosine, and valine levels distinguished complicated patients from patients without complications. Overall, the metabolic pathway analysis suggested that branched-chain amino acid (BCAA) metabolism is significantly compromised in T2DM patients with complications, while perturbation in the metabolism of gluconeogenic amino acids other than BCAAs characterizes both early and advanced T2DM stages. In conclusion, we identified a metabolic serum signature associated with T2DM stages. These data could be integrated with clinical characteristics to build a composite T2DM/complications risk score to be validated in a prospective cohort

Unraveling the protein kinase C/NDRG1 signaling network in breast cancer

N-myc downstream-regulated gene 1 (NDRG1) is a member of the NDRG family of intracellular proteins and plays a central role in a wide range of biological processes including stress response, differentiation, and metabolism. The overexpression of NDRG1 is an indicator of poor prognosis in various types of cancer. Here, we found that NDRG1 is an independent prognostic marker of poor outcome in breast cancer (BC). Analysis of the TCGA dataset showed a significant positive correlation between NDRG1 and PRKCA expression, suggesting a mechanistic role of protein kinase C (PKC) in the regulation of NDRG1. We then assessed the hypothesis that PKC might modulate the activity of NDRG1, and observed that different acute stress conditions converging on PKC activation lead to enhanced NDRG1 expression. This mechanism was found to be specific for NDRG1 as the expression of other NDRG members was not affected. Moreover, CRISPR-based inhibition of NDRG1 expression was obtained in a BC cell line, and showed that this protein is a key driver of BC cell invasion through the Rho-associated coiled-coil containing protein kinase 1 (ROCK1)/phosphorylated cofilin pathway that regulates stress fiber assembly, and the modulation of extracellular matrix reorganization related genes. Together, our findings highlight the potential of NDRG1 as a new BC biomarker and uncover a novel mechanism of regulation of NDRG1 expression that might lead to innovative therapeutic strategies