Silibinin Combination with Arsenic Strongly Inhibits Survival and Invasiveness of Human Prostate Carcinoma Cells

Using Machine Learning to Construct the Blood-Follicle Distribution Models of Various Trace Elements and Explore the Transport-Related Pathways with Multiomics Data

Permeabilities of various trace elements (TEs) through the blood-follicle barrier (BFB) play an important role in oocyte development. However, it has not been comprehensively described as well as its involved biological pathways. Our study aimed to construct a blood-follicle distribution model of the concerned TEs and explore their related biological pathways. We finally included a total of 168 women from a cohort of in vitro fertilization-embryo transfer conducted in two reproductive centers in Beijing City and Shandong Province, China. The concentrations of 35 TEs in both serum and follicular fluid (FF) samples from the 168 women were measured, as well as the multiomics features of the metabolome, lipidome, and proteome in both plasma and FF samples. Multiomics features associated with the transfer efficiencies of TEs through the BFB were selected by using an elastic net model and further utilized for pathway analysis. Various machine learning (ML) models were built to predict the concentrations of TEs in FF. Overall, there are 21 TEs that exhibited three types of consistent BFB distribution characteristics between Beijing and Shandong centers. Among them, the concentrations of arsenic, manganese, nickel, tin, and bismuth in FF were higher than those in the serum with transfer efficiencies of 1.19-4.38, while a reverse trend was observed for the 15 TEs with transfer efficiencies of 0.076-0.905, e.g., mercury, germanium, selenium, antimony, and titanium. Lastly, cadmium was evenly distributed in the two compartments with transfer efficiencies of 0.998-1.056. Multiomics analysis showed that the enrichment of TEs was associated with the synthesis and action of steroid hormones and the glucose metabolism. Random forest model can provide the most accurate predictions of the concentrations of TEs in FF among the concerned ML models. In conclusion, the selective permeability through the BFB for various TEs may be significantly regulated by the steroid hormones and the glucose metabolism. Also, the concentrations of some TEs in FF can be well predicted by their serum levels with a random forest model.

Bioactive compounds from nature: Antioxidants targeting cellular transformation in response to epigenetic perturbations induced by oxidative stress

Oxidative stress results from a persistent imbalance in oxidation levels that promotes oxidants, playing a crucial role in the early and sustained phases of DNA damage and genomic and epigenetic instability, both of which are intricately linked to the development of tumors. The molecular pathways contributing to carcinogenesis in this context, particularly those related to double-strand and single-strand breaks in DNA, serve as indicators of DNA damage due to oxidation in cancer cases, as well as factors contributing to epigenetic instability through ectopic expressions. Oxidative stress has been considered a therapeutic target for many years, and an increasing number of studies have highlighted the promising effectiveness of natural products in cancer treatment. In this regard, we present significant research on the therapeutic targeting of oxidative stress using natural molecules and underscore the essential role of oxidative stress in cancer. The consequences of stress, especially epigenetic instability, also offer significant therapeutic prospects. In this context, the use of natural epi-drugs capable of modulating and reorganizing the epigenetic network is beginning to emerge remarkably. In this review, we emphasize the close connections between oxidative stress, epigenetic instability, and tumor transformation, while highlighting the role of natural substances as antioxidants and epi-drugs in the anti-tumoral context.

Association between urinary arsenic, blood cadmium, blood lead, and blood mercury levels and serum prostate-specific antigen in a population-based cohort of men in the United States

Exposures to heavy metals have been linked to prostate cancer risk. The relationship of these exposures with serum prostate-specific antigen (PSA), a marker used for prostate cancer screening, is unknown. We examined whether total urinary arsenic, urinary dimethylarsonic acid, blood cadmium, blood lead, and total blood mercury levels are associated with elevated PSA among presumably healthy U.S. men. Prostate cancer-free men, aged ≥40 years, were identified from the 2003-2010 National Health and Nutrition Examination Survey. Logistic regression analyses with survey sample weights were used to examine the association between heavy metal levels and elevated PSA for the total population and stratified by black and white race, after adjusting for confounders. There were 5,477 men included. Approximately 7% had elevated PSA. Men with an elevated PSA had statistically significantly higher levels of blood cadmium and blood lead compared to men with a normal PSA (p-values ≤ 0.02), with black men having higher levels. After adjusting for age, race/ethnicity, body mass index, smoking, and education, there was no association found between any of the heavy metal levels and elevated PSA for the total population. In addition, there was no association found when stratified by black and white race. Further investigation is warranted in a larger cohort of men who persistently are exposed to these heavy metals.

Silver Nanoparticles Synthesized Using Carica papaya Leaf Extract (AgNPs-PLE) Causes Cell Cycle Arrest and Apoptosis in Human Prostate (DU145) Cancer Cells

Treatment of cancer has been limited by the poor efficacy and toxicity profiles of available drugs. There is a growing demand to develop alternative approaches to combat cancer such as use of nano-formulation-based drugs. Here, we report biosynthesis and characterization of silver nanoparticles (AgNPs) with papaya leaf extract (PLE) and its anti-cancer properties against different human cancer cells. Purified nanoparticles were characterized by standard techniques, such as TEM, STM, SEM, EDS, XRD, and FTIR. Furthermore, cytotoxic activity of AgNPs-PLE was carried out against different human cancer cells and non-tumorigenic human keratinocytes cells. AgNPs-PLE when compared with AgNPs-citric acid or PLE showed better efficacy against cancer cells and was also relatively less toxic to normal cells. Treatment of DU145 cells with AgNPs-PLE (0.5-5.0 μg/ml) for 24-48 h lowered total cell number by 24-36% (P < 0.05). Inhibition of cell growth was linked with arrest of cell cycle at G2/M phase at 24 h, while G1 and G2/M phase arrests at 48 h. ROS production was observed at earlier time points in presence of AgNPs-PLE, suggesting its role behind apoptosis in DU145 cells. Induction of apoptosis (57%) was revealed by AO/EB staining in DU145 cells along with induction of Bax, cleaved caspase-3, and cleaved PARP proteins. G1-S phase cell cycle check point marker, cyclin D1 was down-regulated along with an increase in cip1/p21 and kip1/p27 tumor suppressor proteins by AgNPs-PLE. These findings suggest the anti-cancer properties of AgNPs-PLE.

Autophagy: Mechanisms and Therapeutic Potential of Flavonoids in Cancer

Autophagy, which is a conserved biological process and essential mechanism in maintaining homeostasis and metabolic balance, enables cells to degrade cytoplasmic constituents through lysosomes, recycle nutrients, and survive during starvation. Autophagy exerts an anticarcinogenic role in normal cells and inhibits the malignant transformation of cells. On the other hand, aberrations in autophagy are involved in gene derangements, cell metabolism, the process of tumor immune surveillance, invasion and metastasis, and tumor drug-resistance. Therefore, autophagy-targeted drugs may function as anti-tumor agents. Accumulating evidence suggests that flavonoids have anticarcinogenic properties, including those relating to cellular proliferation inhibition, the induction of apoptosis, autophagy, necrosis, cell cycle arrest, senescence, the impairment of cell migration, invasion, tumor angiogenesis, and the reduction of multidrug resistance in tumor cells. Flavonoids, which are a group of natural polyphenolic compounds characterized by multiple targets that participate in multiple pathways, have been widely studied in different models for autophagy modulation. However, flavonoid-induced autophagy commonly interacts with other mechanisms, comprehensively influencing the anticancer effect. Accordingly, targeted autophagy may become the core mechanism of flavonoids in the treatment of tumors. This paper reviews the flavonoid-induced autophagy of tumor cells and their interaction with other mechanisms, so as to provide a comprehensive and in-depth account on how flavonoids exert tumor-suppressive effects through autophagy.

Revisiting prostate cancer metabolism: From metabolites to disease and therapy

Prostate cancer (PCa), one of the most commonly diagnosed cancers worldwide, still presents important unmet clinical needs concerning treatment. In the last years, the metabolic reprogramming and the specificities of tumor cells emerged as an exciting field for cancer therapy. The unique features of PCa cells metabolism, and the activation of specific metabolic pathways, propelled the use of metabolic inhibitors for treatment. The present work revises the knowledge of PCa metabolism and the metabolic alterations that underlie the development and progression of the disease. A focus is given to the role of bioenergetic sources, namely, glucose, lipids, and glutamine sustaining PCa cell survival and growth. Moreover, it is described as the action of oncogenes/tumor suppressors and sex steroid hormones in the metabolic reprogramming of PCa. Finally, the status of PCa treatment based on the inhibition of metabolic pathways is presented. Globally, this review updates the landscape of PCa metabolism, highlighting the critical metabolic alterations that could have a clinical and therapeutic interest.

Effects of nonylphenol induced oxidative stress on apoptosis and autophagy in rat ovarian granulosa cells

Nonylphenol (NP) is a kind of environmental endocrine disruptors which is generally recognized to cause female reproductive toxicity, but its basic mechanism has not been fully elucidated. In this study, granulosa cells (GCs) were treated with 0-70 μM NP for 24 h, the cell viability of GCs was reduced significantly, as well as increased cell apoptosis with G2/M arrest. Furthermore, NP significantly induced autophagy and the production of reactive oxygen species (ROS). However, these phenomenons were inhibited by blocking the production of ROS with N-Acetyl-l-cysteine (NAC) administration. Intriguingly, the inhibition of autophagy with 3-Methyladenine (3-MA) could enhance the apoptosis induced by NP. Moreover, the down regulating of p-Akt/Akt, p-mTOR/mTOR and subsequent up-regulation of p-AMPK/AMPK induced by NP can be rescued by pretreatment of NAC. Our findings suggested that NP promotes rat ovarian GCs apoptosis and autophagy simultaneously, which may involve the activation of ROS-dependent Akt/AMPK/mTOR pathway. Whatever, the activation of autophagy is likely to develop a protective mechanism to improve the apoptosis of rat ovarian GCs induced by NP.

Polyphenol-Mediated Autophagy in Cancer: Evidence of In Vitro and In Vivo Studies

One of the hallmarks of cellular transformation is the altered mechanism of cell death. There are three main types of cell death, characterized by different morphological and biochemical features, namely apoptosis (type I), autophagic cell death (type II) and necrosis (type III). Autophagy, or self-eating, is a tightly regulated process involved in stress responses, and it is a lysosomal degradation process. The role of autophagy in cancer is controversial and has been associated with both the induction and the inhibition of tumor growth. Autophagy can exert tumor suppression through the degradation of oncogenic proteins, suppression of inflammation, chronic tissue damage and ultimately by preventing mutations and genetic instability. On the other hand, tumor cells activate autophagy for survival in cellular stress conditions. Thus, autophagy modulation could represent a promising therapeutic strategy for cancer. Several studies have shown that polyphenols, natural compounds found in foods and beverages of plant origin, can efficiently modulate autophagy in several types of cancer. In this review, we summarize the current knowledge on the effects of polyphenols on autophagy, highlighting the conceptual benefits or drawbacks and subtle cell-specific effects of polyphenols for envisioning future therapies employing polyphenols as chemoadjuvants.

Silymarin and Cancer: A Dual Strategy in Both in Chemoprevention and Chemosensitivity

Silymarin extracted from milk thistle consisting of flavonolignan silybin has shown chemopreventive and chemosensitizing activity against various cancers. The present review summarizes the current knowledge on the potential targets of silymarin against various cancers. Silymarin may play on the system of xenobiotics, metabolizing enzymes (phase I and phase II) to protect normal cells against various toxic molecules or to protect against deleterious effects of chemotherapeutic agents on normal cells. Furthermore, silymarin and its main bioactive compounds inhibit organic anion transporters (OAT) and ATP-binding cassettes (ABC) transporters, thus contributing to counteracting potential chemoresistance. Silymarin and its derivatives play a double role, namely, limiting the progression of cancer cells through different phases of the cycle-thus forcing them to evolve towards a process of cell death-and accumulating cancer cells in a phase of the cell cycle-thus making it possible to target a greater number of tumor cells with a specific anticancer agent. Silymarin exerts a chemopreventive effect by inducing intrinsic and extrinsic pathways and reactivating cell death pathways by modulation of the ratio of proapoptotic/antiapoptotic proteins and synergizing with agonists of death domains receptors. In summary, we highlight how silymarin may act as a chemopreventive agent and a chemosensitizer through multiple pathways.

Vimentin Diversity in Health and Disease

Vimentin is a protein that has been linked to a large variety of pathophysiological conditions, including cataracts, Crohn's disease, rheumatoid arthritis, HIV and cancer. Vimentin has also been shown to regulate a wide spectrum of basic cellular functions. In cells, vimentin assembles into a network of filaments that spans the cytoplasm. It can also be found in smaller, non-filamentous forms that can localise both within cells and within the extracellular microenvironment. The vimentin structure can be altered by subunit exchange, cleavage into different sizes, re-annealing, post-translational modifications and interacting proteins. Together with the observation that different domains of vimentin might have evolved under different selection pressures that defined distinct biological functions for different parts of the protein, the many diverse variants of vimentin might be the cause of its functional diversity. A number of review articles have focussed on the biology and medical aspects of intermediate filament proteins without particular commitment to vimentin, and other reviews have focussed on intermediate filaments in an in vitro context. In contrast, the present review focusses almost exclusively on vimentin, and covers both ex vivo and in vivo data from tissue culture and from living organisms, including a summary of the many phenotypes of vimentin knockout animals. Our aim is to provide a comprehensive overview of the current understanding of the many diverse aspects of vimentin, from biochemical, mechanical, cellular, systems biology and medical perspectives.

Oxidative stress and prostatic diseases

Prostatic diseases are a common health problem among males in Western countries, and include chronic prostatic diseases, which have an unclear pathogenesis and few treatment options. In vitro and in vivo studies describe oxidative stress as a major pathway involved in the occurrence of benign prostatic hyperplasia, prostatic cancer and chronic prostatitis. Thus, the oxidative stress cascade is a potential target for the treatment of prostatic diseases. This paper presents a systematic review of the available data concerning the association between oxidative stress and the most common chronic prostatic diseases, and describes the available treatment options that act upon this pathway.

Silibinin suppresses bladder cancer cell malignancy and chemoresistance in an NF-κB signal-dependent and signal-independent manner

Because bladder cancer (BCa) is the 9th most common malignant tumor and 13th leading cause of death due to cancer, therapeutic approaches have attracted a great deal of attention from both clinicians and BCa patients. Although the development of surgery and targeted drugs has brought new challenges for the traditional concept of BCa therapy, various types of chemotherapy remain the final treatment method for many BCa patients. However, chemoresistance inevitably appears, leading to the failure of chemotherapy. Silibinin, a polyphenolic flavonoid component isolated from the fruits or seeds of milk thistle, has been reported to play important roles in inhibiting tumor chemoresistance in breast cancer and head and neck squamous cell carcinomas. Our previous study indicated that silibinin inhibited BCa progression in some mechanisms but with no conclusion of chemoresistance inhibition. Therefore, in the present study, we dissected the role of silibinin in BCa progression and chemoresistance. Our results revealed that in BCa, chemodrug-induced chemoresistance was reversed in the presence of silibinin. Further mechanistic study indicated that silibinin suppressed chemoresistance and BCa malignancy in an NF-κB-dependent and -independent manner. In addition, all of the inhibitory effects were dose‑dependent. Thus, our results provide a potential use for silibinin in BCa therapeutics.

Inhibitory effects of silibinin on proliferation and lung metastasis of human high metastasis cell line of salivary gland adenoid cystic carcinoma via autophagy induction

OBJECTIVE

To investigate the possible mechanisms and effects of silibinin (SIL) on the proliferation and lung metastasis of human lung high metastasis cell line of salivary gland adenoid cystic carcinoma (ACC-M).

METHODS

A methyl thiazolyl tetrazolium assay was performed to detect the inhibitory effects of SIL on the proliferation of ACC-M cells in vitro. Fluorescence microscopy and transmission electron microscopy were used to observe the autophagic process. Western blot was performed to detect the expression of microtube-related protein 1 light-chain 3 (LC3). An experimental adenoid cystic carcinoma (ACC) lung metastasis model was established in nude mice to detect the impacts of SIL on lung weight and lung cancer nodules. Immunohistochemistry was used to detect the expressions of LC3 in human ACC samples and normal salivary gland tissue samples.

RESULTS

SIL inhibited the proliferation of ACC-M cells in a dose- and time-dependent manner, and inductively increased the autophagic bodies in ACC-M cells. Furthermore, SIL could increase the expression of LC3 in ACC-M cells and promote the conversion of LC3-I into LC3-II in a dose- and time-dependent manner. In the ACC lung metastasis model, the lung weight and left and right lung nodules in the SIL-treated group were significantly less than those in the control group (P<0.05). The expressions of LC3-I and LC3-II as well as the positive expression rate of LC3 (80%) significantly increased, but the positive expression of LC3 in human ACC (42.22%) reduced significantly.

CONCLUSION

SIL could inhibit the proliferation and lung metastasis of ACC-M cells by possibly inducing tumor cells autophagy.

Silibinin: a potential old drug for cancer therapy

INTRODUCTION

Silibinin is mixture of flavonolignans extracted from milk thistle and often has been used in the treatment of acute and chronic liver disorders caused by toxins, drug, alcohol and hepatitis and gall bladder disorders for its antioxidant and hepatoprotective properties. Areas covered: However, increasing evidence suggest that silibinin is not solely limited in the treatment of these diseases. Further research suggests that silymarin may function diversely and may serve as a novel therapy for cancer therapy, such as lung cancer, prostatic cancer, colon cancer, breast cancer, bladder cancer and hepatocellular carcinoma by regulating cancer cells growth, proliferation, apoptosis, angiogenesis and many other mechanism. Expert commentary: In this review, in order to provide potential new treatment for these cancer, we summarize the recent anti-cancer findings of silibinin in these cancer and clarify the mechanisms of this effect.

4-Nonylphenol induces apoptosis, autophagy and necrosis in Sertoli cells: Involvement of ROS-mediated AMPK/AKT-mTOR and JNK pathways

The xenoestrogen 4-nonylphenol (NP) induces reproductive dysfunction of male rats, but the fundamental mechanism of this phenomenon is largely unexplored. Sertoli cells (SCs) are pivotal for spermatogenesis and male fertility. The involvement of autophagy in NP-induced apoptotic and necrotic death of SCs was investigated. In this study, 24-h exposure of SCs to 20-30μM NP decreased cell viability, caused G2/M arrest, triggered ΔΨm loss, increased ROS production and induced caspase-dependent apoptosis, necrosis as well as autophagosome formation. NP-induced autophagy was confirmed by monodansylcadaverine-staining and LC3-I/LC3-II conversion. Furthermore, NP up-regulated the (Thr172)p-AMPK/AMPK and (Thr183/185)p-JNK/JNK ratios. This was followed by the down-regulation of (Ser473)p-Akt/Akt, (Thr1462)p-TSC2/TSC2, (Ser2448)p-mTOR/mTOR, (Thr389)p-p70S6K/p70S6K and (Thr37/45)p-4EBP1/4EBP1. Intriguingly, NP-induced apoptosis, autophagy and necrosis could be inhibited through blocking ROS generation by N-acetylcysteine. Autophagy inhibitor 3-MA enhanced NP-induced apoptosis and necrosis. Moreover, The activation of AMPK/mTOR/p70s6k/4EBP1 and JNK signalling pathways induced by NP could be efficiently reversed by pretreatment of N-acetylcysteine or 3-MA. Collectively, our findings provide the first evidence that NP promotes apoptosis, autophagy and necrosis simultaneously in SCs and that this process may involve ROS-dependent JNK- and Akt/AMPK/mTOR pathways. Modulation of autophagy induced by NP may serve as a survival mechanism against apoptosis and necrosis.