FOXO3a/PI3K/Akt pathway participates in the ROS- induced apoptosis triggered by α-ZEL and ß-ZEL.

Zearalenone (ZEN), an estrogenic mycotoxin, is one of the most common food and feed contaminants. Also, its metabolites α-zearalenol (α-ZEL) and ß-zearalenol (ß-ZEL) are considered to induce oxidative stress, however its effect in prostate cells is not known yet. Our previous observations showed that forehead box transcription factor 3a (FOXO3a) expression is modified in hormone- sensitive cells in the response to mycotoxins, similar to the phosphoinositide 3-kinase (PI3K)/ protein kinase B (Akt) pathway. Thus, this study evaluated the direct molecular effect of α-ZEL and ß-ZEL in a dose of 30 µM in hormone-dependent human prostate cancer (PCa) cells with the focus of the involvement of FOXO3a and PI3K/Akt signaling pathway in that effect. We observed that both active metabolites of ZEN reduced cell viability, induced oxidative stress, cell cycle arrest and apoptosis in PCa cells. Furthermore, we observed that FOXO3a as well as PI3K/Akt signaling pathway participate in ZELs induced toxicity in PCa cells, indicating that this signaling pathway might be a regulator of mycotoxin-induced toxicity generally.

The consequences of manipulating relaxin family peptide receptor 1 (RXFP1) level in ovarian cancer cells.

Deregulation of the relaxin family peptide system (RFPS) appears to increase the risk of range of cancers, including epithelial ovarian cancers (EOC). The present study examines the effect of relaxin family peptide receptor 1 (RXFP1) level on the biological properties of human epithelial ovarian adenocarcinoma cells (OVCAR4 and SKOV3). RXFP1 was downregulated (RXFP1↓) in the cells using the RXFP1 sgRNA CRISPR All-in-One Lentivirus set (pLenti-U6-sgRNA-SFFV-Cas9-2A-Puro), and upregulated (RXFP1↑) using the RXFP1 CRISPRa sgRNA Lentivector (pLenti-U6-sgRNA-PGK-Neo) kit, which activates the RXFP1 gene when paired with dCas9-SAM. The changes taking place during adhesion to extracellular matrix (ECM) proteins were assessed in multi-well plates coated with collagen, fibronectin, laminin and gelatin. Cellular viability was monitored based on mitochondrial metabolic activity (MTT Assay, Alamar Blue Assay) and adenosine triphosphate production (ATP Assay). The rate of cell proliferation was determined based on the percentage of Ki67 immunoreactive cells and the numbers of cells in particular cell-cycle phases. The mesenchymal-like (Boyden Chamber Assay) and amoeboid-like movements (Wound Healing Assay) of ovarian cancer cells were also analyzed after transfection. RXFP1 downregulation decreased the adhesion properties of ovarian cancer cells and increased the tendency for apoptosis under stressful conditions. In contrast, RXFP1 upregulation had pro-proliferative, pro-survival and promigratory effects. Our findings confirm that the relaxin-2/RXFP1 signaling pathway plays a role in the promotion of growth and progression of ovarian cancer.

Towards Cancer Nanoradiopharmaceuticals-Radioisotope Nanocarrier System for Prostate Cancer Theranostics Based on Radiation-Synthesized Polymer Nanogels.

Despite the tremendous development of oncology, prostate cancer remains a debilitating malignancy. One of the most promising approaches to addressing this issue is to exploit the advancements of nanomedicine in combination with well-established nuclear medicine and radiotherapy. Following this idea, we have developed a radioisotope nanocarrier platform of electron-beam-synthesized nanogels based on poly(acrylic acid). We have developed a functionalization protocol, showing the very high (>97%) efficiency of the conjugation in targeting a ligand-bombesin derivative. This engineered peptide can bind gastrin-releasing peptide receptors overexpressed in prostate cancer cells; moreover, it bears a radioisotope-chelating moiety. Our nanoplatform exhibits very promising performance in vitro; the radiolabeled nanocarriers maintained high radiochemical purity of >90% in both the labeling buffer and human serum for up to 14 days. The application of the targeted nanocarrier allowed also effective and specific uptake in PC-3 prostate cancer cells, up to almost 30% after 4 h, which is a statistically significant improvement in comparison to carrier-free radiolabeled peptides. Although our system requires further studies for more promising results in vivo, our study represents a vital advancement in radionanomedicine-one of many steps that will lead to effective therapy for castration-resistant prostate cancer.

Estrogen receptor α mediates alternariol-induced apoptosis and modulation of the invasiveness of ovarian cancer cells.

Mycotoxins are secondary metabolites of fungi that may affect both human and animal health. Some of them possess estrogenic activity, due to direct binding to estrogen receptors (ERs) and hence disturb the hormonal balance of the organism. Alternariol (AOH) was previously reported as genotoxic, estrogenic and immunomodulatory agent. However, detailed mechanism of its action has not been fully elucidated. Estrogen receptor α (ERα) was previously reported to modulate the proliferation and invasiveness of ovarian cancer cells. Thus, we decided to verify whether estrogenic-like mycotoxin may affect ovarian cancer cells via ERα. The results showed that AOH induces apoptosis and oxidative stress and that these effects are partially modulated by ERα. Moreover, AOH decreases the invasion and migration of ovarian cancer cells and promotes changes in the expression of genes and proteins that are associated with the invasiveness of cancer i.e. MMP9, SNAIL1/2, ZEB1/2, VIM, CDH1 and CDH2. In conclusion, we postulate that AOH might significantly affect the viability and invasiveness of ovarian cancer cells via modulation of ERα and therefore possibly act as an endocrine disruptive agent in ovarian cancer cells.

Revealing the Role of Alternariol in the Local Steroidogenesis in Human Prostate Normal and Cancer Cells.

The mycotoxin alternariol (AOH) can be found in food products infected by Alternaria spp. and is considered an endocrine-disruptive mycotoxin. The main mechanism of AOH toxicity is associated with DNA damage and modulation of the inflammation process. Still, AOH is considered as one of the emerging mycotoxins. In this study, we have evaluated how AOH might affect the local steroidogenesis process in the prostate, in both normal and cancer cells. We have found that AOH itself modulates the cell cycle, inflammation, and apoptosis, rather than the steroidogenesis process in prostate cancer cells; however, in the presence of another steroidogenic agent, the influence on steroidogenesis is significant. Therefore, this is the first study to report the effect of AOH on local steroidogenesis in normal and prostate cancer cells. We postulate that AOH might modulate the release of the steroid hormones and expression of the key components by interfering with the steroidogenic pathway and might be considered a steroidogenesis-altering agent.

Effect of the mycotoxin deoxynivalenol in combinational therapy with TRAIL on prostate cancer cells.

Tumor necrosis factor-related apoptosis-induced ligand (TRAIL) is reported as a promising anti-cancer therapeutic target. Unfortunately, prostate cancer cells (PCa) are partially resistant to TRAIL-induced apoptosis limiting its therapeutic potential. The existing body of knowledge suggests that naturally produced compounds, such as mycotoxin deoxynivalenol (DON), might potentially sensitize cells to TRAIL treatment and improve the efficiency of therapy. Previously, we observed that DON induces oxidative stress and apoptosis in PCa cell lines. Thus we addressed here whether DON can sensitize PCa cells to TRAIL-induced apoptosis. Our data demonstrates that three out of four tested PCa cell lines pretreated with DON increased TRAIL-induced apoptosis detected with flow cytometry. This effect was associated with oxidative stress (LNCaP and DU-145 cell line) and elevated DNA damage (DU-145, LNCaP, and 22Rv1 cell lines). Next, in the animal model we inoculated PC tumor to SCKID mice followed by administration of DON intraperitoneally and/or TRIAL intravenously. During 21 days monitoring of tumor growth, the animals received 7 doses of DON, TRAIL, DON+TRAIL or control injections. No significant reduction in tumor mass was observed after combinational treatment of TRAIL and DON compared to 1 µg/kg of body weight DON treatment alone, which itself decreased the tumor growth. However, despite the lack of the TRAIL + DON effect, DON itself inducing apoptosis is an interesting compound worth investigating in the context of other combination therapies.

Deoxynivalenol induces apoptosis and autophagy in human prostate epithelial cells via PI3K/Akt signaling pathway.

Phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt) signaling pathway is one of the most deregulated signaling pathway in prostate cancer. It controls basic processes in cells: cell proliferation and death. Any disturbances in the balance between cell death and survival might result in carcinogenesis. Deoxynivalenol (DON) is one of the most common mycotoxins, a toxic metabolites of fungi, present in our everyday diet and feed. Although previous studies reported DON to induce oxidative stress, modulate steroidogenesis, DNA damage and cell cycle modulation triggering together its toxicity, its effect on normal prostate epithelial cells is not known. The aim of the study was to evaluate the effect of DON on the apoptosis and autophagy in normal prostate epithelial cells via modulation of PI3K/Akt signaling pathway. The results showed that DON in a dose of 30 µM and 10 µM induces oxidative stress, DNA damage and cell cycle arrest in G2/M cell cycle phase. The higher concentration of DON induces apoptosis, whereas lower one autophagy in PNT1A cells, indicating that modulation of PI3K/Akt by DON results in the induction of autophagy triggering apoptosis in normal prostate epithelial cells.

Estrogen Receptor ß Participates in Alternariol-Induced Oxidative Stress in Normal Prostate Epithelial Cells.

Alternaria toxins are considered as emerging mycotoxins, however their toxicity has not been fully evaluated in humans. Alternariol (AOH), the most prevalent Alternaria mycotoxin, was previously reported to be genotoxic and to affect hormonal balance in cells; however, its direct molecular mechanism is not known. The imbalance in androgen/estrogen ratio as well as chronic inflammation are postulated as factors in prostate diseases. The environmental agents affecting the hormonal balance might participate in prostate carcinogenesis. Thus, this study evaluated the effect of two doses of AOH on prostate epithelial cells. We observed that AOH in a dose of 10 µM induces oxidative stress, DNA damage and cell cycle arrest and that this effect is partially mediated by estrogen receptor ß (ERß) whereas the lower tested dose of AOH (0.1 µM) induces only oxidative stress in cells. The modulation of nuclear erythroid-related factor 2 (Nrf2) was observed in response to the higher dose of AOH. The use of selective estrogen receptor ß (ERß) inhibitor PHTPP revealed that AOH-induced oxidative stress in both tested doses is partially dependent on activation of ERß, but lack of its activation did not protect cells against AOH-induced ROS production or DNA-damaging effect in case of higher dose of AOH (10 µM). Taken together, this is the first study reporting that AOH might affect basic processes in normal prostate epithelial cells associated with benign and malignant changes in prostate tissue.

In Vitro Analysis of Deoxynivalenol Influence on Steroidogenesis in Prostate.

Deoxynivalenol (DON) is a type-B trichothecene mycotoxin produced by Fusarium species, reported to be the most common mycotoxin present in food and feed products. DON is known to affect the production of testosterone, follicle stimulating hormone (FSH) and luteinizing hormone (LH) in male rats, consequently affecting reproductive endpoints. Our previous study showed that DON induces oxidative stress in prostate cancer (PCa) cells, however the effect of DON on the intratumor steroidogenesis in PCa and normal prostate cells was not investigated. In this study human normal (PNT1A) and prostate cancer cell lines with different hormonal sensitivity (PC-3, DU-145, LNCaP) were exposed to DON treatment alone or in combination with dehydroepiandrosterone (DHEA) for 48 h. The results of the study demonstrated that exposure to DON alone or in combination with DHEA had a stimulatory effect on the release of estradiol and testosterone and also affected progesterone secretion. Moreover, significant changes were observed in the expression of genes related to steroidogenesis. Taken together, these results indicate that DON might affect the process of steroidogenesis in the prostate, demonstrating potential reproductive effects in humans.

Angiotensin II and Angiotensin Receptors 1 and 2-Multifunctional System in Cells Biology, What Do We Know?

For years, the renin-angiotensin system (RAS) has been perceived as a system whose role is to primarily modulate the functioning of the cardiovascular system. Years of research into the role of RAS have provided the necessary data to confirm that the role of RAS is very complex and not limited to the cardiovascular system. The presence of individual elements of the renin-angiotensin (RA) system allows to control many processes, ranging from the memorization to pro-cancer processes. Maintaining the proportions between the individual axes of the RA system allows for achieving a balance, often called homeostasis. Thus, any disturbance in the expression or activity of individual RAS elements leads to pathophysiological processes.

Mycotoxin Alternariol (AOH) Affects Viability and Motility of Mammary Breast Epithelial Cells.

Mycotoxins are present in everyday diet as common food and feed pollutants. A part of them is still concerned as so-called emerging mycotoxins. Due to the lack of toxicity data, the safety limits and detail molecular mechanism have been not established yet for all of them. Alternariol (AOH), as one of these mycotoxins, produced by Alternaria species, is so far reported as an estrogenic, genotoxic, and immunomodulatory agent; however, its direct effect on human health is not known. Especially, in the case of hormone-dependent tissues which are sensitive to both endogenic, as well as external estrogenic agents, it might be crucial to assess the effect of AOH. Thus, this study evaluated how exposure to AOH affects viability and motility of the human normal mammary gland epithelial in vitro model. We observed that AOH significantly affects viability of cells in a time- and dose-dependent manner. Moreover, the induction of oxidative stress, DNA damage, and cell cycle arrest in the G2/M cell cycle phase was observed. The motility of 184A1 cells was also significantly affected. On the molecular level, AOH induced antioxidative stress response via activation of Nuclear factor erythroid 2-related factor 2 (NRF2) signaling pathway agents, as well as decrease in the phosphorylation of protein kinase B (Akt) and p44/42 (ERK 1-2) molecules, indicating that AOH might affect crucial signaling pathways in both physiological and pathophysiological processes in breast tissue.

Methylsulfonylmethane sensitizes endometrial cancer cells to doxorubicin.

BACKGROUND: Methylsulfonylmethane (MSM) is a commonly used diet supplement believed to decrease the inflammation in joints and fastens recovery in osteoarthritis, gastric mucosal injury, or obesity-related disorders. It was also suggested that MSM might play a beneficial role in cancer treatment. PURPOSE: So far, the MSM might have a potentially beneficial effect in endometrial cancer (EC) treatment. STUDY DESIGN: This study evaluated the effect and usefulness of MSM in combinatory therapy with known drug doxorubicin (DOX). METHODS: The effect of combinational treatment of MSM and DOX on the induction of apoptosis was evaluated in EC cell lines (ISHIKAWA, MFE-296, MFE-280). RESULTS: We observed that MSM itself induces apoptosis in EC cell lines, and pre-treatment with MSM for 24 h increases the sensitivity of EC cells to DOX-induced apoptosis and DNA damage and that effect might be regulated by p42/44 (Erk1/2) MAPK and Akt (protein kinase B). CONCLUSION: These results for the first time show that MSM might act as a sensitizer of EC cells to known drugs, for which EC cells quickly acquire resistance. Graphical abstract.

The Influence of Angiotensin Peptides on Survival and Motility of Human High-Grade Serous Ovarian Cancer Cells in Serum Starvation Conditions.

High-grade serous ovarian carcinoma (HGSOC) is the most frequent and malignant form of ovarian cancer. A local renin-angiotensin system (RAS) has been found in the ovary, and changes in selected components of this system were observed in pathological states and also in ovarian cancer. In the present study, we examined the effect of three peptides, Ang-(1-7), Ang-(1-9) and Ang-(3-7), on proliferation and motility of the OVPA8 cell line, a new well-defined and preclinical model of HGSOC. We confirmed the presence of mRNA for all angiotensin receptors in the tested cells. Furthermore, our findings indicate that all tested angiotensin peptides increased the metabolic serum in the medium by activation of cell defense mechanisms such as nuclear factor kappaB signaling pathway andapoptosis. Moreover, tested angiotensin peptides intensified serum starvation-induced cell cycle arrest at the G0/G1 phase. In the case of Ang-(3-7), a significant decrease in the number of Ki67 positive cells (Ki67+) and reduced percentage of activated ERK1/2 levels in ovarian cancer cells were additionally reported. The angiotensin-induced effect of the accumulation of cells in the G0/G1 phase was not observed in OVPA8 cells growing on the medium with 10% FBS. Moreover, in the case of Ang-(3-7), the tendency was quite the opposite. Ang-(1-7) but not Ang-(1-9) or Ang-(3-7) increased the mobility of reluctant-to-migrate OVAP8 cells cultured in the serum-free medium. In any cases, the changes in the expression of VIM and HIF1A gene, associated with epithelial-mesenchymal transition (EMT), were not observed. In conclusion, we speculate that the adaptation to starvation in nutrient-deprived tumors can be modulated by peptides from the renin-angiotensin system. The influence of angiotensin peptides on cancer cells is highly dependent on the availability of growth factors and nutrients.

The Impact of Ang-(1-9) and Ang-(3-7) on the Biological Properties of Prostate Cancer Cells by Modulation of Inflammatory and Steroidogenesis Pathway Genes.

The local renin-angiotensin system (RAS) plays an important role in the pathophysiology of the prostate, including cancer development and progression. The Ang-(1-9) and Ang-(3-7) are the less known active peptides of RAS. This study examines the influence of these two peptide hormones on the metabolic activity, proliferation and migration of prostate cancer cells. Significant changes in MTT dye reduction were observed depending on the type of angiotensin and its concentration as well as time of incubation. Ang-(1-9) did not regulate the 2D cell division of either prostate cancer lines however, it reduced the size of LNCaP colonies formed in soft agar, maybe through down-regulation of the HIF1a gene. Ang-(3-7) increased the number of PC3 cells in the S phase and improved anchorage-independent growth as well as mobility. In this case, a significant increase in MKI67, BIRC5, and CDH-1 gene expression was also observed as well as all members of the NF-kB family. Furthermore, we speculate that this peptide can repress the proliferation of LNCaP cells by NOS3-mediated G2/M cell cycle arrest. No changes in expression of BIRC5 and BCL2/BAX ratio were observed but a decrease mRNA proapoptotic BAD gene was seen. In the both lines, Ang-(3-7) improved ROCK1 gene expression however, increased VEGF and NOS3 mRNA was only seen in the PC3 or LNCaP cells, respectively. Interestingly, it appears that Ang-(1-9) and Ang-(3-7) can modulate the level of steroidogenic enzymes responsible for converting cholesterol to testosterone in both prostate cancer lines. Furthermore, in PC3 cells, Ang-(1-9) upregulated AR expression while Ang-(3-7) upregulated the expression of both estrogen receptor genes. Ang-(1-9) and Ang-(3-7) can impact on biological properties of prostate cancer cells by modulating inflammatory and steroidogenesis pathway genes, among others.

ERß and NFκB-Modulators of Zearalenone-Induced Oxidative Stress in Human Prostate Cancer Cells.

Nuclear factor kappa-light-chain-enhancer of activated B cells (NFκB) is commonly expressed in prostate cancer (PCa) cells and is associated with increased proliferation, metastases and androgen independence. Zearalenone (ZEA) is one of the most common mycotoxins contaminating food, which might mimic estrogens and bind to estrogen receptors (ERs). The ratio of androgens to estrogens in men decreases physiologically with age, and is believed to participate in prostate carcinogenesis. In this study, we evaluated the role of NFκB and ERß in the induction of oxidative stress in human PCa cells by ZEA. As observed, ZEA at a dose of 30 µM induces oxidative stress in PCa cells associated with DNA damage and G2/M cell cycle arrest. We also observed that the inhibition of ERß and NFΚB via specific inhibitors (PHTPP and BAY 117082) significantly increased ZEA-induced oxidative stress, although the mechanism seems to be different for androgen-dependent and androgen-independent cells. Based on our findings, it is possible that the activation of ERß and NFΚB in PCa might protect cancer cells from ZEA-induced oxidative stress. We therefore shed new light on the mechanism of ZEA toxicity in human cells.

The opposite effects of angiotensin 1-9 and angiotensin 3-7 in prostate epithelial cells.

There is growing evidence that renin-angiotensin system (RAS) components have been involved in the development of various types of cancers, including prostate cancer. This article for the first time reports the impact of Ang1-9 and Ang3-7 on viability and proliferation, migration and invasion of epithelial prostate cells. The results of this study clearly show that Ang1-9 and Ang3-7 exert different/opposite effects on in vitro biological properties of prostate cells. It appears that Ang1-9 has pro-cancer activities via the ability to induce cell divisions, enhance cell motility and stimulate the expression of such genes as vascular endothelial growth factor (VEGF), hypoxia-inducible factors (HIF-1), vimentin (VIM) and REL proto-oncogene, NF-kB subunit (REL). On the contrary, Ang3-7 did not show any mitogenic activity. Furthermore, this peptide hormone limited the migration of PNT1A cells probably by downregulation of VEGF and VIM expression. Finally, it is worth noting that both angiotensins have the ability to modulate gene expression for angiotensin receptors. Unfortunately, we could not unequivocally identify the type of angiotensin receptor responsible for signal transduction pathway involved in PNT1A cell survival and proliferation. Undoubtedly, further research and testing in this area are necessary.

Deoxynivalenol Modulates the Viability, ROS Production and Apoptosis in Prostate Cancer Cells.

Deoxynivalenol (DON), known as vomitoxin, a type B trichothecene, is produced by Fusarium. DON frequently contaminates cereal grains such as wheat, maize, oats, barley, rye, and rice. At the molecular level, it induces ribosomal stress, inflammation and apoptosis in eukaryotic cells. Our findings indicate that DON modulates the viability of prostate cancer (PCa) cells and that the response to a single high dose of DON is dependent on the androgen-sensitivity of cells. DON appears to increase reactive oxygen species (ROS) production in cells, induces DNA damage, and triggers apoptosis. The effects of DON application in PCa cells are influenced by the mitogen-activated protein kinase (MAPK) and NFΚB- HIF-1α signaling pathways. Our results indicate that p53 is a crucial factor in DON-associated apoptosis in PCa cells. Taken together, our findings show that a single exposure to high concentrations of DON (2-5 µM) modulates the progression of PCa.

Estrogen receptor ß plays a protective role in zearalenone-induced oxidative stress in normal prostate epithelial cells.

Zearalenone (ZEA) - a fungal mycotoxin is reported to both cause the oxidative stress associated with death of cells as well as induction of the proliferation of cells, depending on its concentration and the type of cells. ZEA due to its structural similarity to naturally occurring estrogens is able to bind to estrogen receptors and triggers estrogen-associated signaling pathways. The aim of this study is to evaluate whether the induction of oxidative stress in normal epithelial prostate PNT1A cells is associated with estrogenic activity of ZEA. We observed that ZEA-induced oxidative stress in PNT1A cells is associated with a decrease in the oxidative stress defense enzymes expression, cell cycle arrest in G2/M cell cycle phase as well as the decreased migration of cells. The results also suggest that the observed effect might be associated with the nuclear factor kappa-light-chain-enhancer of activated B cells (NFκB)- hypoxia inducible factor 1 alpha (HIF-1α) signaling pathway. The usage of estrogen receptor ß (ERß) selective antagonist 4-[2-phenyl-5,7-bis(trifluoromethyl)pyrazolo[1,5-a]pyrimidin-3-yl]-phenol PHTPP showed that ERß activity is able to decrease the ZEA-induced oxidative stress, but is not enough to counteract it, indicating that ZEA-induced oxidative stress is only partially associated with estrogenic activity of ZEA.

Methylsulfonylmethane (organic sulfur) induces apoptosis and decreases invasiveness of prostate cancer cells.

A major challenge in the management of prostate cancer (PC) is to limit tumor growth and metastases. Targeted therapies applying natural compounds might be potentially useful in PC treatment. Methylsulfonylmethane (MSM), also known as organic sulfur, is a dietary supplement used for various clinical purposes, mostly known for its anti-inflammatory properties. Therefore, we decided to evaluate the effect of MSM on PC cells LNCaP, PC3 and DU-145 which represent different in vitro models of PC. We observed that MSM decreases the viability and invasiveness of PC cells through the induction of apoptosis and cell cycle arrest in the G0/G1 cell cycle phase. Moreover, MSM in a low dose (200 mM) is able to reduce the migration and invasion of PC cells. Considering the low overall body toxicity and insignificant side effects of MSM, its apoptosis-inducing properties might be used in PC treatment in the future.

Angiotensin 1-7 modulates molecular and cellular processes central to the pathogenesis of prostate cancer.

Angiotensin 1-7 (Ang1-7) is an endogenous bioactive component of the renin-angiotensin system (RAS). In addition to its cardiovascular properties, its anti-proliferative and anti-angiogenic traits are believed to play important roles in carcinogenesis. The present study examines the influence of Ang1-7 on processes associated with development and progression of prostate cancer cells. Our findings indicate that while Ang1-7 (1 nM; 48 h) can effectively reduce cell proliferation in DU-145, it can induce a significant decrease in the expression of MKI67 in LNCaP. In both cell lines we also observed a reduction in colony size in soft agar assay. A various changes in gene expression were noted after exposure to Ang1-7: those of anti- and pro-apoptotic agents and the NF-kB family of transcription factors, as well as mesenchymal cell markers and vascular endothelial growth factor A (VEGFA). In addition, Ang1-7 was found to modulate cell adhesion and matrix metallopeptidase (MMP) activity. Changes were also observed in the levels of angiotensin receptors and sex steroid hormone receptors. Ang1-7 reduced the levels of estrogen receptor alpha gene (ESR1) and increased the expression of estrogen receptor beta gene (ESR2) in all prostate cancer cells; it also up-regulated androgen receptor (AR) expression in androgen-sensitive cells but contradictory effect was observed in androgen- irresponsive cell lines. In summary, the results confirm the existence of complex network between the various elements of the local RAS and the molecular and cellular mechanisms of prostate cancerogenesis. The response of cancer cells to Ang1-7 appears to vary dependently on the dose and time of incubation as well as the aggressiveness and the hormonal status of cells.