Effects of a phthalate metabolite mixture on both normal and tumoral human prostate cells

Abstract

Phthalates represent a group of substances used in industry that have antiandrogenic activity and are found in different concentrations in human urine and plasma. More than 8 million tons of phthalates are used each year, predominantly as plasticizers in polyvinyl chloride (PVC) products. Phthalates are widely used in everyday consumer products and improperly discarded into the environment. Furthermore, in vivo studies carried out in our laboratory showed that a mixture of phthalates, equivalent to the mixture used in this study, deregulated the expression of genes and miRNAs associated with prostatic carcinogenic pathways. Thus, this study was designed to establish an in vitro model to assess pathways related to cell survival, proliferation, apoptosis, and biosynthesis of miRNAs, using both normal and tumoral prostatic epithelial cells exposed to an environmentally relevant mixture of phthalate metabolites.Tumor (LNCaP) and normal (PNT-2) prostatic epithelial cell lines were exposed for 24 and 72 h to vehicle control or the phthalate mixture. The selected metabolite mixture (1000 μmol/L) consisted of 36.7% monoethyl phthalate (MEP), 19.4% mono (2-ethylhexyl) phthalate (MEHP), 15.3% monobutyl phthalate (MBP), 10.2% monoisobutyl phthalate (MiBP), 10.2% monoisononyl phthalate (MiNP), and 8.2% monobenzyl phthalate (MBzP). Gene expression was performed by qRT-PCR and cell migratory potential was measured using cell migration assays. Our results showed that the mixture of phthalates increased cell turnover, oxidative stress, biosynthesis, and expression of miRNAs in LNCaP cells; thus, increasing their cellular expansive and migratory potential and modulating tumor behavior, making them possibly more aggressive.However, these effects were less pronounced in benign cells, demonstrating that, in the short term, benign cells are able to develop effective mechanisms or more resistance against the insult.

In silico investigation of the role of miRNAs in a possible developmental origin of prostate cancer in F1 and F2 offspring of mothers exposed to a phthalate mixture

“…Our previous results showed that maternal exposure to a phthalate mixture altered the expression of microRNAs in the ovary and ventral prostate of rat offspring 15,18 . Likewise, phthalate monoester mixture exposure modulated benign and tumor human prostate cells and increased the expression of the miR‐184 and miR‐141‐3p in vitro 37 . The results presented here agreed with the microRNA sequencing profile presented by Scarano et al 15 and were correlated with some oncogenic targets by in silico analysis.…”

“…15,18 Likewise, phthalate monoester mixture exposure modulated benign and tumor human prostate cells and increased the expression of the miR-184 and miR-141-3p in vitro. 37 The results presented here agreed with the microRNA sequencing profile presented by Scarano et al 15 and were correlated with some oncogenic targets by in silico analysis. Furthermore, our results showed that the perinatally phthalate exposure can modify the rno-miR-184 expression in the prostate up to the F2 generation.…”

Effects of Dibutylphthalate and Steroid Hormone Mixture on Human Prostate Cells

“…Phthalates have been detected in human blood, milk, and urine [ 66 , 79 , 80 ]. Several studies have identified a direct relationship between the exposure to phthalates and pathologies of different organs and systems such as metabolic disorders, damage to the reproductive system, and hormone-sensitive cancers [ 54 , 80 , 81 ], including breast cancer [ 66 , 82 ]. However, the relationship between phthalate and prostate gland pathologies needs further investigation [ 66 ].…”

“…These results suggest that DEHP-induced fluctuations of estrogen and androgen levels might underlie the predisposition of prostatic enlargement. In industrialized countries, benign and malignant prostate disorders are among the most common diseases in men [ 53 , 54 ]. Worldwide, PCa represents the second-most common solid tumor in men [ 25 , 55 ], being the second-most prevalent global cancer in 2020, with the sixth highest cancer mortality rate, and accounting for up to 7.3% of all global cancer incidence [ 6 , 56 ].…”

“…As another kind of cancer, prostate cancer is characterized by multiple biological processes including several genetic and epigenetic alterations that affect epithelial cells, considered the main target cells. It has been demonstrated that the long and complex process of prostate carcinogenesis can be also influenced by lifestyle factors such as diet, alcoholism, smoking, and obesity [ 37 , 54 , 57 , 58 ]. It is widely recognized that exposure to chemical compounds such as phthalates and other EDCs plays an important role in the development of PCa [ 25 , 59 , 60 ], which is considered a hormone-dependent tumor [ 6 , 61 ].…”