Microarray analysis of altered long non-coding RNA expression profile in liver cancer cells treated by ginsenoside Rh2

Ginsenosides in cancer: Targeting cell cycle arrest and apoptosis

Despite the existence of extensive clinical research and novel therapeutic treatments, cancer remains undefeated and the significant cause of death worldwide. Cancer is a disease in which growth of cells goes out of control, being also able to invade other parts of the body. Cellular division is strictly controlled by multiple checkpoints like G1/S and G2/M which, when dysregulated, lead to uncontrollable cell division. The current remedies which are being utilized to combat cancer are monoclonal antibodies, chemotherapy, cryoablation, and bone marrow transplant etc. and these have also been greatly disheartening because of their serious adverse effects like hypotension, neuropathy, necrosis, leukemia relapse and many more. Bioactive compounds derived from natural products have marked the history of the development of novel drug therapies against cancer among which ginsenosides have no peer as they target several signaling pathways, which when abnormally regulated, lead to cancer. Substantial research has reported that ginsenosides like Rb1, Rb2, Rb3, Rc, Rd, Rg3, Rh2 etc. can prevent and treat cancer by targeting different pathways and molecules by induction of autophagy, neutralizing ROS, induction of cancerous cell death by controlling the p53 pathway, modulation of miRNAs by decreasing Smad2 expression, regulating Bcl-2 expression by normalizing the NF-Kb pathway, inhibition of inflammatory pathways by decreasing the production of cytokines like IL-8, causing cell cycle arrest by restricting cyclin E1 and CDC2, and induction of apoptosis during malignancy by decreasing β-catenin levels etc. In this review, we have analyzed the anti-cancer therapeutic potential of various ginsenoside compounds in order to consider their possible use in new strategies in the fight against cancer.

Ginsenoside Rh2 Regulates the CFAP20DC-AS1/MicroRNA-3614-3p/BBX and TNFAIP3 Axis to Induce Apoptosis in Breast Cancer Cells

While a number of coding genes have explained the anticancer activity of ginsenoside Rh2, little is known about noncoding RNAs. This study was performed to elucidate the regulatory activity of long noncoding RNA (lncRNA) CFAP20DC-AS1, which is known to be downregulated by Rh2. MiR-3614-3p, which potentially binds CFAP20DC-AS1, was screened using the LncBase Predicted program, and the binding was verified by assaying the luciferase activity of a luciferase/lncRNA recombinant plasmid construct. The competitive endogenous RNA (ceRNA) relationship of the two RNAs was further validated by quantitative PCR after deregulation of each RNA using siRNA. The effect of miRNA and target genes on the MCF-7 cancer cell growth was determined by monitoring proliferation and apoptosis in the presence of Rh2 after deregulating the corresponding gene. The miRNA decreased the luciferase activity of the luciferase/CFAP20DC-AS1 fusion vector, confirming the binding. SiRNA-based deregulation of CFAP20DC-AS1 attenuated the expression of miR-3614-3p and vice versa. In contrast to CFAP20DC-AS1, miR-3614-3p was upregulated by Rh2, inhibiting proliferation but stimulating apoptosis of the MCF-7 cells. Target genes of miR-3614-3p, BBX and TNFAIP3, were downregulated by Rh2 and the miRNA but upregulated by the lncRNA. Rh2 inhibits CFAP20DC-AS1, which obscures the association of the lncRNA with miR-3614-3p, resulting in the suppression of oncogenic BBX and TNFAIP3. Taken together, the Rh2/CFAP20DC-AS1/miR-3614-3p/target gene axis contributes to the antiproliferation activity of Rh2 in cancer cells.

Targeting long non coding RNA by natural products: Implications for cancer therapy

In spite of achieving substantial progress in its therapeutic strategies, cancer-associated prevalence and mortality are persistently rising globally. However, most malignant cancers either cannot be adequately diagnosed at the primary phase or resist against multiple treatments such as chemotherapy, surgery, radiotherapy as well as targeting therapy. In recent decades, overwhelming evidences have provided more convincing words on the undeniable roles of long non-coding RNAs (lncRNAs) in incidence and development of various cancer types. Recently, phytochemical and nutraceutical compounds have received a great deal of attention due to their inhibitory and stimulatory effects on oncogenic and tumor suppressor lncRNAs respectively that finally may lead to attenuate various processes of cancer cells such as growth, proliferation, metastasis and invasion. Therefore, application of phytochemicals with anticancer characteristics can be considered as an innovative approach for treating cancer and increasing the sensitivity of cancer cells to standard prevailing therapies. The purpose of this review was to investigate the effect of various phytochemicals on regulation of lncRNAs in different human cancer and evaluate their capabilities for cancer treatment and prevention.

Ginsenoside Rh2 upregulates long noncoding RNA STXBP5-AS1 to sponge microRNA-4425 in suppressing breast cancer cell proliferation

Background

Ginsenoside Rh2, a major saponin derivative in ginseng extract, is recognized for its anticancer activities. Compared to coding genes, studies on long noncoding RNAs (lncRNAs) and microRNAs (miRNAs) that are regulated by Rh2 in cancer cells, especially on competitive endogenous RNA (ceRNA) are sparse.

Methods

LncRNAs whose promoter DNA methylation level was significantly altered by Rh2 were screened from methylation array data. The effect of STXBP5-AS1, miR-4425, and RNF217 on the proliferation and apoptosis of MCF-7 breast cancer cells was monitored in the presence of Rh2 after deregulating the corresponding gene. The ceRNA relationship between STXBP5-AS1 and miR-4425 was examined by measuring the luciferase activity of a recombinant luciferase/STXBP5-AS1 plasmid construct in the presence of mimic miR-4425.

Results

Inhibition of STXBP5-AS1 decreased apoptosis but stimulated growth of the MCF-7 cells, suggesting tumor-suppressive activity of the lncRNA. MiR-4425 was identified to have a binding site on STXBP5-AS1 and proven to be downregulated by STXBP5-AS1 as well as by Rh2. In contrast to STXBP5-AS1, miR-4425 showed pro-proliferation activity by inducing a decrease in apoptosis but increased growth of the MCF-7 cells. MiR-4425 decreased luciferase activity from the luciferase/STXBP5-AS1 construct by 26%. Screening the target genes of miR-4425 and Rh2 revealed that Rh2, STXBP5-AS1, and miR-4425 consistently regulated tumor suppressor RNF217 at both the RNA and protein level.

Conclusion

LncRNA STXBP5-AS1 is upregulated by Rh2 via promoter hypomethylation and acts as a ceRNA, sponging the oncogenic miR-4425. Therefore, Rh2 controls the STXBP5-AS1/miR-4425/RNF217 axis to suppress breast cancer cell growth.

Modulation of Long Non-Coding RNAs by Different Classes of Secondary Metabolites from Plants: A Mini-Review on Antitumor Effects

The broad pharmacological spectrum of plants is related to their secondary metabolism, which is responsible for the synthesis of different compounds that have multiple effects on cellular physiology. Among the biological effects presented by phytochemicals, their use for the prevention and treatment of cancer can be highlighted. This occurs due to several mechanisms of antitumor action demonstrated by these compounds, including regulation of the cell signaling pathways and inhibition of tumor growth. In this way, long non-coding RNAs (lncRNAs) appear to be promising targets for the treatment of cancer. Their deregulation has already been related to a variety of clinical-pathological parameters. However, the effects of secondary metabolites on lncRNAs are still restricted. For this reason, the present review aimed to gather data on phytochemicals with action on lncRNAs in order to confirm their possible antitumor potential. According to the literature, terpenoid and flavonoid are the main examples of secondary metabolites involved with lncRNAs activity. In addition, the lncRNAs H19, CASC2, HOTAIR, NKILA, CCAT1, MALAT1, AFAP1-AS1, MEG3, and CDKN2B-AS1 can be highlighted as important targets in the search for new anti-tumor agents since they act as modulating pathways related to cell proliferation, cell cycle, apoptosis, cell migration and invasion. Finally, challenges for the use of natural products as a commercial drug were also discussed. The low yield, selectivity index and undesirable pharmacokinetic parameters were emphasized as a difficulty for obtaining these compounds on a large scale and for improving the potency of its biological effect. However, the synthesis and/or development of formulations were suggested as a possible approach to solve these problems. All of these data together confirm the potential of secondary metabolites as a source of new anti-tumor agents acting on lncRNAs.

Natural products: Potential targets of TME related long non-coding RNAs in lung cancer

BACKGROUND

Lung cancer is a significant health concern worldwide due to high mortality and morbidity, despite the advances in diagnosis, treatment, and management. Recent experimental evidence from different models suggested long non-coding RNAs (lncRNAs) as major modulators of cancer stem cells (CSCs) in the tumor microenvironment (TME) to support metastasis and drug resistance in lung cancer. Evidence-based studies demonstrated that natural products interfere with TME functions.

PURPOSE OF STUDY

To establish lncRNAs of TME as novel targets of natural compounds for lung cancer management.

STUDY DESIGN

Current study used a combination of TME and lung CSCs, lncRNAs and enrichment and stemness maintenance, natural products and stem cell management, natural products and lncRNAs, natural products and targeted delivery as keywords to retrieve the literature from Scopus, Web of Science, PubMed, and Google Scholar. This study critically reviewed the current literature and presented cancer stem cells' ability in reprogramming lung TME.

RESULTS

This review found that TME related oncogenic and tumor suppressor lncRNAs and their signaling pathways control the maintenance of stemness in lung TME. This review explored natural phenolic compounds and found that curcumin, genistein, quercetin epigallocatechin gallate and ginsenoside Rh2 are efficient in managing lung CSCs. They modulate lncRNAs and their upstream mediators by targeting signaling and epigenetic pathways. This review also identified relevant nanotechnology-based phytochemical delivery approaches for targeting lung cancer.

CONCLUSION

By critical literature analysis, TME related lncRNAs were identified as potential therapeutic targets, aiming to develop natural product-based therapeutics to treat metastatic and drug-resistant lung cancers.

Advances in Biocatalytic Synthesis, Pharmacological Activities, Pharmaceutical Preparation and Metabolism of Ginsenoside Rh2

Ginsenoside Rh2 (3β-O-Glc-protopanaxadiol), a trace but characteristic pharmacological component of red ginseng, exhibited versatile pharmacological activities, such as antitumor effects, improved cardiac function and fibrosis, anti-inflammatory effects, antibiosis and excellent medicinal potential. In recent years, increased research has been performed on the biocatalytic synthesis of ginsenoside Rh2. In this paper, advances in the biocatalytic synthesis, pharmacological activities, pharmaceutical preparation and metabolism of ginsenoside Rh2 are reviewed.

Knockdown of p62/sequestosome enhances ginsenoside Rh2-induced apoptosis in cervical cancer HeLa cells with no effect on autophagy

p62/sequestosome is a multifunctional adaptor protein that participates in a wide variety of cellular processes. 20(S)-Ginsenoside Rh2 (G-Rh2) has various biological effects, including anticancer activity. We found that G-Rh2 can induce apoptosis and autophagy in HeLa cells. G-Rh2 significantly enhanced the transcriptional level of p62. A siRNA was constructed to knock down p62 and assess its effect on apoptosis induced by G-Rh2. p62 protein levels were successfully downregulated in cells transfected with the p62-specific siRNA. Silencing of p62 further decreased cell viability while also enhancing cell apoptosis, reactive oxygen species generation, the ratio of Bax to Bcl-2, and the cleavage of PARP. p62 knockdown decreased expression levels of Nrf2. Moreover, silencing of p62 had no significant effect on autophagy induced by G-Rh2. These results suggest that combining G-Rh2 treatment with inhibition of p62 may be a potential treatment strategy for cervical cancer.

Therapeutic effects of ginsenosides on breast cancer growth and metastasis

Breast cancer is the most common cause of cancer-related deaths among women worldwide. Thus, the development of new and effective low-toxicity drugs is vital. The specific characteristics of breast cancer have allowed for the development of targeted therapy towards each breast cancer subtype. Nevertheless, increasing drug resistance is displayed by the changing phenotype and microenvironments of the tumor through mutation or dysregulation of various mechanisms. Recently, emerging data on the therapeutic potential of biocompounds isolated from ginseng have been reported. Therefore, in this review, various roles of ginsenosides in the treatment of breast cancer, including apoptosis, autophagy, metastasis, epithelial-mesenchymal transition, epigenetic changes, combination therapy, and drug delivery system, have been discussed.

Ginsenoside Rh2 activates α-catenin phosphorylation to inhibit lung cancer cell proliferation and invasion

The efficacy of ginsenoside Rh2 (Rh2) in cancer therapy has been reported; however, its function in lung cancer remains unknown. To analyze the role of Rh2 in the inhibition of lung cancer cell proliferation in the present study, protein expression levels of E-cadherin, vimentin, β-catenin, Smo, Gli1, and α-catenin were assessed by western blotting, whilst mRNA expression levels of TCF7 FZD8, Smo, Gli1, Gli2, and Gli3 were determined by reverse transcription-quantitative PCR in the A549 cell line. Phosphorylation sites were detected by proteomic methods and cell proliferation was analyzed by MTT assay. The present study revealed that Rh2 treatment significantly inhibited cell proliferation. Western blotting indicated that the expression levels of E-cadherin were increased and vimentin was downregulated in Rh2-treated cells compared with control cells. Treatment of A549 cells with Rh2 suppressed phosphorylation of five distinct proteins and increased phosphorylation of nine proteins. Among them, the phosphorylation of α-catenin at S641 was significantly induced. Rh2 treatment suppressed the expression levels of key genes involved in Wnt (Wnt3, transcription factor 7 and frizzled class receptor 8) and hedgehog [smoothened, frizzled class receptor (Smo), GLI family zinc finger (Gli)1, Gli2, and Gli3] signaling. Immunoblotting results indicated that β-catenin, Smo and Gli1 protein expression levels were also suppressed by treatment with Rh2 compared with control treatment. Expression of α-catenin S641D, a phosphomimetic form of α-catenin, inhibited the accumulation of β-catenin and Gli1 and inhibited cell proliferation and invasion. Furthermore, knockdown of β-catenin (CTNNB1) or Gli1 with specific small interfering RNAs inhibited cell proliferation, whereas overexpression of these genes had an opposite effect. Additionally, overexpression of β-catenin or Gli1 activated cell proliferation, even in the presence of Rh2, suggesting that Rh2 affects A549 cell proliferation through inhibition of Wnt and hedgehog signaling by phosphorylation of α-catenin at S641. Together, these data suggested that Rh2 treatment may inhibit the proliferation of A549 lung cancer cells. Further exploration of the underlying mechanism by which Rh2 inhibits cell proliferation is warranted.

2-Deoxy-Rh2: A novel ginsenoside derivative, as dual-targeting anti-cancer agent via regulating apoptosis and glycolysis

20(S)-Rh2 is a ginsenoside isolated from Panax ginseng, which exhibits anti-cancer activities on various human cancer cells. A novel 20(S)-Rh2 derivative, 2-Deoxy-Rh2 was synthesized and hybridized with protopanaxadiol and 2-deoxy-glucose in an attempt to enhance the anticancer activity. Through screening the antitumor effect against various cell lines by MTT assay, 2-Deoxy-Rh2 especially resulted in a concentration-dependent and time-dependent inhibition of viability in MCF-7 human breast cancer cells. Multiple methods were used to explore the cellular and molecular mechanisms of 2-Deoxy-Rh2 as a potent anti-cancer agent. In MCF-7 cells, 2-Deoxy-Rh2 triggered apoptosis, stimulated ROS production and disrupted normal mitochondrial membrane potential. Meantime, 2-Deoxy-Rh2 eff ;ectively suppressed the glucose uptake capabilities and intracellular ATP production. The cellular oxygen consumption rate (OCR) and extracellular acidification rate (ECAR) were significantly decreased in response to 2-Deoxy-Rh2, which were carried out to assess the overall glycolytic flux and mitochondrial respiration. Docking studies and molecular dynamics simulations were performed to verify the binding mode of 2-DG and 2-Deoxy-Rh2 with hexokinase II, with results showing that 2-Deoxy-Rh2 could easily fit into the similar active site of 2-DG, finally binding to hexokinase II to suppress glycolysis. Taken together, the results suggest that 2-Deoxy-Rh2 exhibited remarkable anticancer activity based on regulating mitochondrial apoptosis pathway, dampening glycolysis and inhibiting mitochondrial respiration, which support development of 2-Deoxy-Rh2 as a potential agent for cancer therapy.