A resveratrol analog, phoyunbene B, induces G2/M cell cycle arrest and apoptosis in HepG2 liver cancer cells

Bioactive natural products from orchids native to the Americas - A review

The purpose of this review is to provide information on the traditional uses, phytochemical and pharmacological studies performed with species of orchids native to the Americas and the Caribbean Islands. The treatment of inflammation is the most traditional use for plants of this family, specially in Central America, while anti-inflammatory and anticancer assays are oftenly reported in pharmacological investigations. From the chemical point of view, they are sources of phenanthrenoids and stilbenes, rare secondary metabolites not commonly found in other families of plants, as well as cycloartane triterpenes, pyrrolizidine alkaloids and flavonoids. Since just few species were chemically and pharmacologically studied, in comparison to the large number of native species (less than 0.5% of the total), the orchids of the New World may be an interesting niche for the discovery of new, bioactive natural products.

Applications of resveratrol in the treatment of gastrointestinal cancer

Natural product compounds have lately attracted interest in the scientific community as a possible treatment for gastrointestinal (GI) cancer, due to their anti-inflammatory and anticancer properties. There are many preclinical, clinical, and epidemiological studies, suggesting that the consumption of polyphenol compounds, which are abundant in vegetables, grains, fruits, and pulses, may help to prevent various illnesses and disorders from developing, including several GI cancers. The development of GI malignancies follows a well-known path, in which normal gastrointestinal cells acquire abnormalities in their genetic composition, causing the cells to continuously proliferate, and metastasize to other sites, especially the brain and liver. Natural compounds with the ability to affect oncogenic pathways might be possible treatments for GI malignancies, and could easily be tested in clinical trials. Resveratrol is a non-flavonoid polyphenol and a natural stilbene, acting as a phytoestrogen with anti-cancer, cardioprotective, anti-oxidant, and anti-inflammatory properties. Resveratrol has been shown to overcome resistance mechanisms in cancer cells, and when combined with conventional anticancer drugs, could sensitize cancer cells to chemotherapy. Several new resveratrol analogs and nanostructured delivery vehicles with improved anti-GI cancer efficacy, absorption, and pharmacokinetic profiles have already been developed. This present review focuses on the in vitro and in vivo effects of resveratrol on GI cancers, as well as the underlying molecular mechanisms of action.

Experience of Endoscopic Endonasal Approach for 803 Pituitary Tumors With Cavernous Sinus Invasion

OBJECTIVE

The aim of this study was to investigate the effectiveness, safety, complications, and prognosis of endoscopic endonasal surgery for pituitary adenomas with cavernous sinus invasion (CSI).

METHODS

The clinical data of 803 pituitary adenomas with CSI surgeries performed in our single ward between January 1, 2006 and December 31, 2018 were retrospectively reviewed. The resection degree, bone invasion, endocrine examination, complications, and outcome were retrospectively summarized.

RESULTS

Gross total resection was achieved in 394 patients (49.1%) subtotal resection in 171 patients (21.3%) and partial resection in 238 patients (29.6%). Clinically variable analyses showed that there was a significant correlation between CSI and female, older age, operation history, and non-gross total resection (NGTR). Among the pituitary adenomas with CSI, there was a significant correlation between bone invasive and NGTR, Knosp classification, recurrence. K-M curves showed that young age, larger tumors, bilateral invasion, Grade 4 of Knosp classification, NGTR, and bone invasion were associated with pituitary adenomas regrowth. Multivariate analysis revealed that bone invasion, NGTR, and Grade 4 of Knosp classification were independent risk factors for pituitary adenomas regrowth. There was a significant correlation between CSI and female, older age, operation history, and tumor resection degree.

CONCLUSIONS

There was a significant correlation between CSI and female, older age, operation history, and tumor resection degree. The patients with CSI and bone invasion were likely to recurrent. Non-gross total resection, bone invasion, and Grade 4 of Knosp classification were independent risk factors for pituitary adenomas regrowth. Endoscopic endonasal surgery is an excellent choice for pituitary adenomas with CSI.

Anticancer Potential of Resveratrol, β-Lapachone and Their Analogues

This review aims to explore the potential of resveratrol, a polyphenol stilbene, and beta-lapachone, a naphthoquinone, as well as their derivatives, in the development of new drug candidates for cancer. A brief history of these compounds is reviewed along with their potential effects and mechanisms of action and the most recent attempts to improve their bioavailability and potency against different types of cancer.

Effects of Resveratrol, Berberine and Their Combinations on Reactive Oxygen Species, Survival and Apoptosis in Human Squamous Carcinoma (SCC-25) Cells

Background:

Levels of cellular Reactive Oxygen Species (ROS) influence the oxidized/reduced states of cellular proteins, and create redox-signaling pathways that can activate transcription factors, kinases, and phosphatases. ROS levels can be increased radically by external factors, including ionizing and UV radiation or exposure to chemical compounds. These increased ROS levels can, in turn, lead to oxidative damage of DNA. Natural plant treatments against cancer can modulate these processes by inducing or decreasing ROS production.

Methods:

Here we report new observations that squamous carcinoma (SCC-25) cells, exposed to 24 hours of combined resveratrol and berberine treatment, contain increased ROS levels. Using flow cytometry, for drug activity characteristics, an accumulation of ROS was observed. A combination of different dyes, CellROX Green (Life Technologies) and DCFH-DA (Sigma), allowed for flow cytometric estimation of levels of cellular ROS as well as cellular localization.

Results:

Live staining and microscopic observations confirmed the accumulation of ROS in SCC-25 cells following a combination treatment at concentrations of 10μg/ml. Additionally, the cytotoxicity of the compounds was significantly improved after their combined application. Additive effects were observed for doses lower than the calculated IC50 of berberine [IC50=23µg/ml] and resveratrol [IC50=9µg/ml]. Viability (MTS) assays and analysis of isobolograms revealed a significant impact on cell viability upon combination treatment.

Conclusion:

These results suggest that administration of berberine, in the presence of resveratrol, could be decreased even to 50% (half the IC50 for berberine) for cancer treatment.

Regulating the CCNB1 gene can affect cell proliferation and apoptosis in pituitary adenomas and activate epithelial-to-mesenchymal transition

The aim of the present study was to investigate the role and potential regulatory mechanisms of cyclin B1 (CCNB1) in the proliferation, apoptosis and epithelial-to-mesenchymal transition (EMT) in pituitary adenomas. A total of 24 specimens were included in the present study. The expression levels of CCNB1 protein in two normal pituitary and 22 pituitary adenoma tissues were determined by western blotting. CCNB1 was knocked-down by lentiviral-mediated infection of short hairpin RNA (shRNA) in GH3 and MMQ cell lines. The proliferation, cell cycle and apoptosis of GH3 and MMQ cell lines were detected using a Cell Counting Kit-8 and flow cytometer. Reverse transcription-quantitative PCR was utilized to detect the expression level of CCNB1 gene and EMT markers. In the present study, resveratrol (RES) was used as an inhibitor of CCNB1. The protein expression level of CCNB1 in pituitary adenomas was higher than that in normal pituitary tissue, as assessed by western blot analysis. In addition, the expression level of CCNB1 in invasive pituitary adenomas was higher when comparing invasive pituitary adenomas and non-invasive pituitary adenomas. Knockdown of CCNB1 resulted in significant decreases in cell viability and proliferation, arrested cell cycle at the G₂/M phase and increased apoptosis. In addition, knockdown of CCNB1 significantly decreased the expression levels of the mesothelial cell marker N-cadherin (P<0.001), but significantly increased the expression levels of the epithelial cell markers E-cadherin (P<0.01) and p120-catenin (P<0.001). Further analyses identified that RES inhibited the expression level of CCNB1, and RES treatment exhibited a similar effect as CCNB1 shRNA infection. The present study suggested that suppressing the expression level of CCNB1 could regulate the proliferation and apoptosis of pituitary tumor cells and alter the expression level of various EMT markers. In addition, RES treatment could be used as an inhibitor of CCNB1. The present study also identified the molecular mechanisms underlying CCNB1 role in EMT.

Integrated systems-genetic analyses reveal a network target for delaying glioma progression

Objective

To identify a convergent, multitarget proliferation characteristic for astrocytoma transformation that could be targeted for therapy discovery.

Methods

Using an integrated functional genomics approach, we prioritized networks associated with astrocytoma progression using the following criteria: differential co‐expression between grade II and grade III IDH1‐mutated and 1p/19q euploid astrocytomas, preferential enrichment for genetic risk to cancer, association with patient survival and sample‐level genomic features. Drugs targeting the identified multitarget network characteristic for astrocytoma transformation were computationally predicted using drug transcriptional perturbation data and validated using primary human astrocytoma cells.

Results

A single network, M2, consisting of 177 genes, was associated with glioma progression on the basis of the above criteria. Functionally, M2 encoded physically interacting proteins regulating cell cycle processes and analysis of genome‐wide gene‐regulatory interactions using mutual information and DNA–protein interactions revealed the known regulators of cell cycle processes FoxM1, B‐Myb, and E2F2 as key regulators of M2. These results suggest functional disruption of M2 via gene mutation or altered expression as a convergent pathway regulating astrocytoma transformation. By considering M2 as a multitarget drug target regulating astrocytoma transformation, we identified several drugs that are predicted to restore M2 expression in anaplastic astrocytoma toward its low‐grade profile and of these, we validated the known antiproliferative drug resveratrol as down‐regulating multiple nodes of M2 including at nanomolar concentrations achievable in human cerebrospinal fluid by oral dosing.

Interpretation

Our results identify M2 as a multitarget network characteristic for astrocytoma progression and encourage M2‐based drug screening to identify new compounds for preventing glioma transformation.

Therapeutic Versatility of Resveratrol Derivatives

Resveratrol, a natural phytoalexin, exhibits a remarkable range of biological activities, such as anticancer, cardioprotective, neuroprotective and antioxidant properties. However, the therapeutic application of resveratrol was encumbered for its low bioavailability. Therefore, many researchers focused on designing and synthesizing the derivatives of resveratrol to enhance the bioavailability and the pharmacological activity of resveratrol. During the past decades, a large number of natural and synthetic resveratrol derivatives were extensively studied, and the methoxylated, hydroxylated and halogenated derivatives of resveratrol received particular more attention for their beneficial bioactivity. So, in this review, we will summarize the chemical structure and the therapeutic versatility of resveratrol derivatives, and thus provide the related structure activity relationship reference for their practical applications.

Chemical constituents of Pholidota cantonensis

Two 9,10-dihydrophenanthrenes trivially named phocantol and phocantone, two diterpenoid glycosidesnamed phocantoside A and phocantoside B were isolated from the ethanol extract of the air-dried whole plant of Pholidota cantonensis Rolfe, together with seventeen known compounds. The structures of the four compounds were identified as 1-hydroxy-2,7-dimethoxy-9,10-dihydrophenanthro-[4,5-bcd]furan, 5-hydroxy-2,7-dimethoxy-9,10-dihydro-1,4-phenanthrenedione, (8R,13E)-ent-labd-13-ene-3α,8,15-triol 15-O-β-D-gluco-pyranoside and (5S,8R,9S,10R)-cis-cleroda-3,13(E)-diene-15,18-diol 15-O-β-D-glucopyranosyl-18-O-β-D-glucopyranoside by chemical and spectroscopic methods, including 1D and 2D NMR. Twenty compounds were evaluated for their cytotoxic activities against mouse leukemia p388D1 cancer cells, and compound phocantone, phocantoside A, tanshinone IIA and syringate exhibited cytotoxic activity against the mouse leukemia p388D1 cancer cells with IC₅₀ values ranging from 13.37 to 27.5 μM.

Effect of resveratrol on cancer progression through the REG Ⅲ expression pathway in head and neck cancer cells

Identification of reliable markers of chemo- and radiosensitivity and the key molecules that enhance the susceptibility of head and neck squamous cell carcinoma (HNSCC) to anticancer treatments is highly desirable. Previously, we have reported that regenerating gene (REG) Ⅲ expression was such a marker associated with an improved survival rate for HNSCC patients. In the present study, we investigated the stimulators for induction of REG Ⅲ expression using REG Ⅲ promoter assay in HNSCC cells transfected with REG Ⅲ promoter vector. We tested inflammatory cytokines, growth factors, polyphenols, PPARγ activator of thiazolidinediones, and histone deacetylase inhibitors, and found that 3,4',5-trihydroxy-trans-stilbene (resveratrol) significantly increased the REG Ⅲ promoter activity and the mRNA levels of REG Ⅲ in HNSCC cells. Moreover, we demonstrated the effect of resveratrol on cancer cell progression, such as cell proliferation, chemo‑ and radiosensitivity and cancer invasion of HNSCC cells. Resveratrol significantly inhibited cell growth, enhanced chemo‑ and radiosensitivity, and blocked cancer invasion of HNSCC cells. These data suggested that resveratrol could inhibit cancer progression through the REG Ⅲ expression pathway in HNSCC cells.

Role of Natural Stilbenes in the Prevention of Cancer

Natural stilbenes are an important group of nonflavonoid phytochemicals of polyphenolic structure characterized by the presence of a 1,2-diphenylethylene nucleus. Stilbenes have an extraordinary potential for the prevention and treatment of different diseases, including cancer, due to their antioxidant, cell death activation, and anti-inflammatory properties which associate with low toxicity under in vivo conditions. This review aims to discuss various approaches related to their mechanisms of action, pharmacological activities in animal models and humans, and potential chemoprevention in clinical studies. The biological activity of natural stilbenes is still incompletely understood. Furthermore, after administration to animals or humans, these molecules are rapidly metabolized. Thus pharmacokinetics and/or activities of the natural structures and their metabolites may be very different. Novel drug formulations have been postulated in order to improve stability and bioavailability, to minimize side effects, and to facilitate interaction with their domains in target proteins. These pharmacological improvements should lead stilbenes to become effective candidates as anticancer drugs.

Resveratrol and liver: A systematic review

Background:

Recent studies demonstrated that resveratrol has many therapeutic effects on liver disorders. Resveratrol significantly increased survival after liver transplantation, decreased fat deposition, necrosis, and apoptosis which induced by ischemia in Wistar rats. It provided liver protection against chemical, cholestatic, and alcohol injury. Resveratrol can improve glucose metabolism and lipid profile and decrease liver fibrosis and steatosis. Furthermore, it was able to alter hepatic cell fatty acid composition. According to extension of liver disease around the world and necessity of finding new threat, this review critically examines the current preclinical in vitro and in vivo studies on the preventive and therapeutic effects of resveratrol in liver disorders.

Materials and Methods:

A search in PubMed, Google Scholar, and Scopus was undertaken to identify relevant literature using search terms, including “liver,” “hepatic,” and “Resveratrol.” Both in vivo and in vitro studies were included. No time limiting considered for this search.

Results:

A total of 76 articles were eligible for this review. In these articles, resveratrol shows antioxidative properties in different models of hepatitis resulting in reducing of hepatic fibrosis.

Conclusion:

Resveratrol could reduce hepatic steatosis through modulating the insulin resistance and lipid profile in animals. These high quality preclinical studies propose the potential therapeutic implication of resveratrol in liver disorders especially those with hepatic steatosis. Resveratrol can play a pivotal role in prevention and treatment of liver disorders by reducing hepatic fibrosis.

Cancer prevention and therapy through the modulation of the tumor microenvironment

Cancer arises in the context of an in vivo tumor microenvironment. This microenvironment is both a cause and consequence of tumorigenesis. Tumor and host cells co-evolve dynamically through indirect and direct cellular interactions, eliciting multiscale effects on many biological programs, including cellular proliferation, growth, and metabolism, as well as angiogenesis and hypoxia and innate and adaptive immunity. Here we highlight specific biological processes that could be exploited as targets for the prevention and therapy of cancer. Specifically, we describe how inhibition of targets such as cholesterol synthesis and metabolites, reactive oxygen species and hypoxia, macrophage activation and conversion, indoleamine 2,3-dioxygenase regulation of dendritic cells, vascular endothelial growth factor regulation of angiogenesis, fibrosis inhibition, endoglin, and Janus kinase signaling emerge as examples of important potential nexuses in the regulation of tumorigenesis and the tumor microenvironment that can be targeted. We have also identified therapeutic agents as approaches, in particular natural products such as berberine, resveratrol, onionin A, epigallocatechin gallate, genistein, curcumin, naringenin, desoxyrhapontigenin, piperine, and zerumbone, that may warrant further investigation to target the tumor microenvironment for the treatment and/or prevention of cancer.

Anti-tumor effects and cellular mechanisms of resveratrol

Resveratrol (3, 5, 4'-trihydroxystilbene) is a phytoalexin contained in a variety of plants, such as grapes, berries and especially in the dried roots of Polygonum cuspidatum Sieb. et Zucc. It has been shown to exhibit anti-oxidative and anti-inflammation activity, and to reverse the effects of aging. Its ability to suppress cell proliferation, induce apoptosis and suppress the metastasis and invasion in a number of cell lines has prompted a large interest from people for its use as an anti-tumor component. In this review, evidence of resveratrol's anti-tumor effects and molecular mechanisms are recapitulated. First, we present the anti-apoptosis, anti-invasion/metastasis and anti-inflammation effect of resveratrol; second, the main signaling pathways involved in these activities are described and summarized with the studies of different tumors involved. Resveratrol not only induces apoptosis of tumor cells through intrinsic/extrinsic pathways and cell cycle arrest, but also inhibits the invasion and metastasis abilities of tumors via modulating collagen degradation-related molecular targets. Altogether, the present findings suggest the anti-tumor potential of resveratrol against various types of cancers.

Regulation by resveratrol of the cellular factors mediating liver damage and regeneration after acute toxic liver injury

BACKGROUND AND AIM

Acute liver injury is manifested by different degree of hepatocyte necrosis and may recover via the process of hepatocyte regeneration once the injury is discontinued. Most of the liver injury is associating with inflammatory cytokines. Resveratrol (RSV) is a natural phytoalexin with powerful anti-inflammatory effects.

AIM

The effects of RSV on cellular factors mediating liver damage and regeneration in acute carbon tetrachloride (CCl4 ) liver injury were investigated.

RESULTS

RSV decreased alanine aminotransferase, aspartate aminotransferase, necrosis, and 4-hydroxynonenal in the CCl4 -injured liver. RSV decreased hepatocyte apoptosis by reducing caspase 8 and caspase 3 but not Bax and Bcl-xL. RSV reduced Kupffer cells recruitment, the expressions of tumor necrosis factor-α and interleukin-6, but not interleukin-10. RSV lowered the numbers of anti-5-bromon-2'-deoxyuridine and anti-Ki67-positive hepatocytes. Hepatic hepatocyte growth factor, c-Met and transforming growth factor-α expressions were reduced by RSV, while transforming growth factor-β1 and hepatic stellate cells activation were not changed. RSV reduced the injury-induced CXCL10 elevations in serum and liver in vivo. Besides, RSV inhibited CXCL10 release from CCl4 -injured hepatocytes in vitro. In contrast, recombinant CXCL10 improved the viability of CCl4 -injured hepatocytes.

CONCLUSIONS

RSV therapy can be beneficial for acute toxic liver injury. RSV reduced hepatocyte apoptosis but limited hepatocyte regeneration possibly through reducing the hepatomitogenic signaling and the release of CXCL10.

Synergistic anti-proliferative effect of resveratrol and etoposide on human hepatocellular and colon cancer cell lines

Resveratrol is an active component of grape, which has been shown to inhibit proliferation of a wide variety of tumor cells. The ability of resveratrol to enhance anti-proliferative effects of etoposide in wild type p53 liver carcinoma (HepG2) and colon cancer (HCT-116) cells was investigated with focusing on p53 activation. HepG2 cells and HCT-116 cells were treated with resveratrol and/or etoposide in a time- and dose-dependent manner and their proliferative response was evaluated by XTT assay. The expression of p53 protein was assessed using Western blot. Resveratrol exerted anti-proliferative activity on both cell types in a dose (25-100 μM)- and time (24-72 h)-dependent manner. Interestingly in HepG2 cells, resveratrol exhibited the same levels of cytotoxicity as etoposide (10 μM) when the cells treated with ≥ 25 μM for 48-72 h. In contrast to HepG2, resveratrol significantly enhanced anti-proliferative effects of etoposide in HCT-116 cells. P53 expression was up-regulated by resveratrol and etoposide and pre-incubation of both cells with resveratrol increased levels of etoposide-induced p53 expression. In line with cytotoxicity effect, combination therapy showed stronger activation of p53 in HCT-116 compared to HepG2. It seems that resveratrol exerts differential synergistic effect with etoposide on proliferation of cancer cells from different origin which is mainly accompanied by p53 activation. Our data represent a future strategy to provide much safer and more effective treatment for colon cancer.