Geraniin suppresses ovarian cancer growth through inhibition of NF-κB activation and downregulation of Mcl-1 expression

Geraniin: A dietary ellagitannin as a modulator of signalling pathways in cancer progression

Cancer remains a global health challenge, necessitating the exploration of novel therapeutic agents. Current treatment options are unable to overwhelm and cure the cancer burden. Hence, identifying new bioactive molecular entities with potent anticancer activity is the need of the hour. Ellagitannin Geraniin (GN) is one such evidence-based novel bioactive molecular entity (BME) available from different natural sources that can effectively combat cancer. This narrative review attempts to investigate the potential of BME-GN from 2005 to 2023 as an efficient molecular anti-cancer therapeutic against diverse cancers. We provide information on GN's pharmacological advantages, metabolite profile, and capacity to modulate multiple molecular targets involved in the hallmarks of cancer. Using the search terms "Geraniin," "Gallic acid," "Ellagitannin," "pharmacological properties," "health," "antioxidant," "apoptosis," "disease management," "anti-proliferative," "in vitro," "anti-inflammatory," "anti-angiogenic," "in vivo," and "clinical trials," We searched the scientific literature using Scopus, Web of Science, Google Scholar, and PubMed. We removed publications that included overlap or equivalent content and used the most recent review on each issue as our primary reference. From an initial pool of 430 articles, 52 studies met the search criteria. These studies collectively provide substantial in vitro, in vivo, and clinical evidence of GN's potential to combat diverse cancers. Mechanistic insights revealed its involvement in fostering apoptosis, anti-inflammatory, and modulation of key signalling pathways implicated in the hallmarks of cancer. GN's pleiotropic pharmacological and molecular therapeutic properties strongly suggest its potential as a promising anticancer agent.

Fuzheng Jiedu Decoction Induces Apoptosis and Enhances Cisplatin Efficacy in Ovarian Cancer Cells In Vitro and In Vivo through Inhibiting the PI3K/AKT/mTOR/NF-κB Signaling Pathway

Objectives

This study is aimed at investigating the anticancer activity of Fuzheng Jiedu decoction (FJD) alone or in combination with cisplatin in ovarian cancer (OC) models, as well as its underlying mechanisms of action.

Methods

The anticancer activities of FJD, cisplatin, and the combination of the PI3K inhibitor (LY294002, LY) or activator (IGF-1) were evaluated in OC cell lines in vitro and in a SKOV3 xenograft mouse model in vivo. The cell proliferation and invasion ability were measured using MTT, EdU, and transwell assays, respectively. The cell apoptosis was examined by flow cytometry and JC-1 assays. The expression levels of the Bcl-2 family and the PI3K/AKT/mTOR/NF-κB pathway-related proteins were analyzed by Western blot.

Results

The in vivo and in vitro studies showed that FJD administration could significantly inhibit cell proliferation and promote cell apoptosis in two OC cell lines SKOV3 and 3AO and partially decreased the tumor volumes and weights. In addition, FJD could significantly downregulate the protein levels of p-PI3K/PI3K, p-AKT/AKT, p-mTOR/mTOR, NF-κB, p38, and Bcl-2 and upregulate the Bax, Cyt-C, and cleaved caspase-3 in OC tumor tissues and cells. FJD cotreatment increased the efficacy of cisplatin, including inhibiting OC cell proliferation and invasion, promoting cell apoptosis, and inhibiting the PI3K/AKT/mTOR signaling pathway, while this enhancement was suppressed by IGF-1. Similarly, LY also enhanced the anticancer efficacy of cisplatin.

Conclusions

This study indicated that FJD could improve the efficacy of cisplatin by inhibiting the PI3K/AKT/mTOR/NF-κB signaling pathway. It is suggested that FJD may be a valuable adjuvant drug for the treatment of OC.

CircACC1 Promotes NSCLC Proliferation via miR-29c-3p/MCL-1 Signaling Pathway

Non-small cell lung cancer remains the leading cause of cancer-related deaths worldwide with high morbidity and mortality. There is an urgent need to reveal new molecular mechanisms that contribute to NSCLC progression to facilitate drug development and to improve overall survival. Much attention has been paid to the role of circRNAs in NSCLC development. However, the knowledge of circRNAs in NSCLC is still limited, and need to be further explored. The dysregulation of circACC1 was evaluated by qRT-PCR in NSCLC samples and cell lines. The oncogenic role of circACC1 in NSCLC progression was analyzed by CCK8 and colony formation assays. The interaction between the circACC1 and miR-29c-3p, as well as MCL-1, was verified by qRT-PCR, Western blot, luciferase reporter assay, and RIP experiment. Elevated levels of circACC1 were found in NSCLC patients and were negatively correlated with OS. Ectopic expression of circACC1 promoted the capacity of cell growth and clonogenicity, while the inhibition of circACC1 decreased the proliferation and clonogenicity potential. Mechanism studies elucidated that circACC1 contributes to cell growth via directly binding to miR-29c-3p. Transfection of miR-29c-3p mimic blocked circACC1 mediated NSCLC cell proliferation. MCL-1 is a downstream target of miR-29c-3p in NSCLC cells. The circACC1/miR-29c-3p/MCL-1 axis is important in NSCLS proliferation.

Geraniin inhibits whole blood IFN-γ and IL-6 and promotes IL-1β and IL-8, and stimulates calcium-dependent and sucrose-sensitive erythrocyte death

Correlations between circulating cytokine levels and disease states are well established, and pharmacological modulation of the immune response is thus an important aspect of the assessment of investigational new drugs. Moreover, chemotherapy-related anemia is a major obstacle in cancer treatment. Geraniin (GRN), a tannin extracted from Geranium and other plants, possesses promising antitumor potential. However, the effect of GRN on whole blood (WB) cytokine response and RBC physiology remains unexplored. Heparinized blood from consented, healthy adults was challenged with 100 ng/mL of lipopolysaccharide (LPS) with and without pretreatment with 10 μM of GRN for 24 h at 37 °C, and tumor necrosis factor-α (TNF-α), interferon-γ (IFN-γ), interleukin-1β (IL-1β), IL-6, IL-8, and IL-10 were assayed by ELISA. Moreover, single-cell RBC suspensions were treated with 5-100 μM of GRN for 24 or 48 h at 37 °C and cytotoxicity and canonical eryptotic markers were examined by flow cytometry. It was revealed that GRN significantly attenuated LPS-induced IFN-γ levels, increased IL-1β, decreased IL-6 only in absence of LPS, and aggravated LPS-induced IL-8 while together with LPS significantly diminished IL-10. Furthermore, GRN induced dose-responsive, Ca²⁺-dependent, and sucrose-sensitive hemolysis, along with phosphatidylserine exposure and Ca²⁺ accumulation with no appreciable cell shrinkage or oxidative damage. GRN was also selectively toxic to platelets, significantly delayed reticulocyte maturation, and significantly disrupted leukocyte proportions. In conclusion, GRN regulates the WB cytokine response and promotes premature hemolysis and eryptosis. This study provides insights into the therapeutic utility of GRN in a highly relevant cellular model system.

Antiviral Role of Phenolic Compounds against Dengue Virus: A Review

Phenolic compounds have been related to multiple biological activities, and the antiviral effect of these compounds has been demonstrated in several viral models of public health concern. In this review, we show the antiviral role of phenolic compounds against dengue virus (DENV), the most widespread arbovirus globally that, after its re-emergence, has caused multiple epidemic outbreaks, especially in the last two years. Twenty phenolic compounds with anti-DENV activity are discussed, including the multiple mechanisms of action, such as those directed against viral particles or viral proteins, host proteins or pathways related to the productive replication viral cycle and the spread of the infection.

Geraniin Protects PC12 Cells Against Aβ25-35-Mediated Neuronal Damage: Involvement of NF-κB and MAPK Signaling Pathways

β-amyloid peptide (Aβ) has been considered a critical factor that is associated with the development of oxidative stress and neuroinflammation in the pathogenesis of Alzheimer's disease. This study was performed to evaluate the effect of geraniin on Aβ_25-35-caused oxidative damage and neuroinflammatory response, and its underlying mechanism. Geraniin protected pheochromocytoma12 (PC12) cells from Aβ_25-35-mediated cell death by reducing oxidative stress and restoring cell cycle dysregulation. Moreover, geraniin markedly attenuated Aβ-triggered DNA injury that was partially associated with decreases in caspase-3 activity. Moreover, the compound significantly downregulated the release of neuroinflammatory factors. Upregulation of nuclear factor-κB activity was suppressed by geraniin, which was due to suppression of JNK, ERK1/2, and the p38 mitogen-activated protein kinase (MAPK) pathway. This was the first study to support further understanding of geraniin as a promising agent against neurotoxicity in the reduction of oxidative stress and neuroinflammation.

MCL1 regulates cell death, tumor growth and chemosensitivity to sabutoclax in ovarian adenocarcinoma

This research was conducted to study the role of MCL1 in ovarian adenocarcinoma cell death and survival as well as chemosensitivity to sabutoclax. Both in vitro and in vivo assays including qRT-PCR, Western blot, CCK-8, caspase 3/7 activation, colony foci formation assay and xenograft assay were conducted. Except for the xenograft assay, the other experiments were conducted at the cellular level and they were carried out to assess cell activities such as viability, programmed death and proliferation. SKOV3 and OVCAR3 cell lines were used as the cell models for all experiments. It was proved that MCL1 was overexpressed in ovarian adenocarcinoma (tissues and cells) at RNA and protein levels. MCL1 knockdown was also discovered to suppress the viability and proliferation of ovarian adenocarcinoma cells in vivo and in vitro. Lastly, it was found that MCL1 knockdown significantly promoted ovarian carcinoma cell death and the sensitivity to sabutoclax. Thus, we concluded that MCL1 acted as a cancer facilitator in ovarian adenocarcinoma and it is also a suppressor of sabutoclax sensitivity.

The Promising Role of Plant Tannins as Bioactive Antidiabetic Agents

BACKGROUND

Plant tannins are polyphenolic substances with various molecular weights and a variable complexity. Due to the beneficial effects for controlling chronic disorders particularly diabetes mellitus, this class of secondary metabolites has gained more interest in the recent years.

OBJECTIVE

We aimed through this review to collect, analyze and discuss all available information related to the antidiabetic effect of isolated tannins (including both condensed and hydrolysable varieties) and tannin-rich plants as well as the possible mechanisms of action involved in this antidiabetic activity.

METHODS AND RESULTS

Our bibliographic research was conducted to gather more than 41 medicinal plants containing tannins and 19 isolated tannins and tannin-rich crud extracts which were revealed to possess glucose lowering effect according to pharmacological studies.

CONCLUSION

Hence, according to findings of the present review, tannins could be useful for prevention and management of diabetes mellitus and its associated complications and these natural products could be promising compounds for the discovery of new hypoglycemic agents.

Geraniin inhibits oral cancer cell migration by suppressing matrix metalloproteinase-2 activation through the FAK/Src and ERK pathways

Geraniin has been reported to have numerous biological activities, including antiviral, antihypertensive, antihyperglycaemic, liver protective, antidiabetic, and apoptotic activities. However, the anti-migration effects of geraniin on oral cancer remain elusive. In this study, we revealed the potential antitumor mechanisms of geraniin through the inhibition of the migration and invasion of human oral cancer cell lines SCC-9 and SCC-14. The results of gelatin zymography and Western blot assays revealed that geraniin significantly reduced the activity and expression of matrix metalloproteinase-2 (MMP-2) of oral cancer cells in a concentration-dependent manner. Furthermore, geraniin potently suppressed the phosphorylation of focal adhesion kinase (FAK), Src, and extracellular signal-regulated kinase (ERK)1/2 but did not affect the phosphorylation of p38 mitogen-activated protein kinase (MAPK) and c-Jun N-terminal kinase 1/2. Moreover, blocking the MAPK/ERK1/2 pathway significantly enhanced the anti-migration ability of geraniin in oral cancer cells. In conclusion, we demonstrated that geraniin inhibits the motility of SCC-9 and SCC-14 cells in vitro through a molecular mechanism that involves the attenuation of MMP-2 expression and activity mediated by decreased FAK/Src and ERK1/2 pathways.

Geraniin Differentially Modulates Chromosome Stability of Colon Cancer and Noncancerous Cells by Oppositely Regulating their Spindle Assembly Checkpoint

Geraniin has been reported to specifically induce apoptosis in multiple human cancers, but the underlying mechanism is poorly defined. The spindle assembly checkpoint (SAC) is a surveillance system to ensure high-fidelity chromosome segregation during mitosis. Weakening of SAC to enhance chromosome instability (CIN) can be therapeutic because very high levels of CIN are lethal. In this study, we have investigated the effects of geraniin on the SAC of colorectal cancer HCT116 cells and noncancerous colon epithelial CCD841 cells. We find that treatment of HCT116 cells with geraniin leads to dose-dependent decrease of cell proliferation, colony formation, and anchorage-independent growth. Geraniin is found to induce apoptosis in mitotic and postmitotic HCT116 cells. Furthermore, geraniin weakens the SAC function of HCT116 cells by decreasing the transcriptional expression of several SAC kinases (particularly Mad2 and Bub1), which in turn leads to premature anaphase entry, mitotic aberrations, and CIN in HCT116 cells. In contrast, the proliferation of CCD841 cells is slightly inhibited by geraniin. Even more interestingly, geraniin increases the transcriptional expression of several SAC kinases (e.g., Mad1 and BubR1) to strengthen SAC efficiency, which contributes to the reduction of mitotic aberrations and CIN in CCD841 cells. Altogether, our findings reveal that the SAC pathway in human colon cancer and noncancerous cell lineages responses oppositely to geraniin treatment, resulting CIN promotion and suppression, respectively. Specific abrogation of SAC to induce catastrophic CIN in HCT116 cells may account for the selective anticancer action of geraniin.. Environ. Mol. Mutagen. 60:254-268, 2019. © 2018 Wiley Periodicals, Inc.

MGMT-activated DUB3 stabilizes MCL1 and drives chemoresistance in ovarian cancer

Chemoresistance is a severe outcome among patients with ovarian cancer that leads to a poor prognosis. MCL1 is an antiapoptotic member of the BCL-2 family that has been found to play an essential role in advancing chemoresistance and could be a promising target for the treatment of ovarian cancer. Here, we found that deubiquitinating enzyme 3 (DUB3) interacts with and deubiquitinates MCL1 in the cytoplasm of ovarian cancer cells, which protects MCL1 from degradation. Furthermore, we identified that O⁶-methylguanine-DNA methyltransferase (MGMT) is a key activator of DUB3 transcription, and that the MGMT inhibitor PaTrin-2 effectively suppresses ovarian cancer cells with elevated MGMT-DUB3-MCL1 expression both in vitro and in vivo. Most interestingly, we found that histone deacetylase inhibitors (HDACis) could significantly activate MGMT/DUB3 expression; the combined administration of HDACis and PaTrin-2 led to the ideal therapeutic effect. Altogether, our results revealed the essential role of the MGMT-DUB3-MCL1 axis in the chemoresistance of ovarian cancer and identified that a combined treatment with HDACis and PaTrin-2 is an effective method for overcoming chemoresistance in ovarian cancer.

Dichloromethane Extracts of Geranium Koreanum Kom. Alleviates Esophagus Damage in Acute Reflux Esophagitis-Induced Rats by Anti-Inflammatory Activities

Reflux esophagitis (RE) is a gastrointestinal disease caused by the reflux of gastric acid and stomach contents, and it leads to esophageal damage. Therefore, it is necessary to study the improvement of esophageal damage on a RE-induced model. The present study was accomplished to demonstrate the protective effects of a dichloromethane fraction of Geranium koreanum (DGK) plant on esophageal damage in an acute RE rat model. First, we examined the potential of anti-inflammatory effects of various fractions measured by cell cytotoxicity, morphological changes and nitric oxide (NO) production on lipopolysaccharide (LPS)-induced Raw 264.7 macrophage cells. Then, to evaluate the protective effects on RE, rats were partitioned into the following groups: normal control, RE-induced control and RE rats pre-treated with DGK 100 and 200 mg/kg body weight. The esophageal mucosal ulcer ratio was measured by the Image J program and histological changes were examined using a hematoxylin and eosin staining of the esophageal mucosa. The expression of pro-inflammatory proteins, cytokines and tight junction proteins involved in the esophageal mucosal damage were investigated using Western blotting and an enzyme-linked immunosorbent assay (ELISA) kit with esophagus tissue. DGK chemical profile and phenolic contents were analyzed by liquid chromatography-mass spectrometry (LC-MS/MS). The results showed that DGK exhibited anti-inflammatory effects against LPS-stimulated cells by significantly inhibiting NO production. Additionally, the results in vivo showed that improvement effects of DGK on esophageal mucosal damage. The expression of inflammatory proteins involved in nuclear factor κB (NF-κB) signaling pathways and tight junction protein (claudin-4 and -5) were significantly decreased in esophageal mucosa. We found the potential of DGK as source of replacement therapy products for inflammatory and RE disease.

An increased autophagic flux contributes to the anti-inflammatory potential of urolithin A in macrophages

BACKGROUND

An extract of Phyllanthus muellerianus and its constituent geraniin have been reported to exert anti-inflammatory activity in vivo. However, orally consumed geraniin, an ellagitannin, shows low bioavailability and undergoes metabolization to urolithins by gut microbiota. This study aimed at comparing geraniin and urolithin A with respect to inhibition of M1 (LPS) polarization of murine J774.1 macrophages and shedding more light on possible underlying mechanisms.

METHODS

Photometric, fluorimetric as well as luminescence-based assays monitored production of reactive oxygen species (ROS) and nitric oxide (NO), cell viability or reporter gene expression. Western blot analyses and confocal microscopy showed abundance and localization of target proteins, respectively.

RESULTS

Urolithin A is a stronger inhibitor of M1 (LPS) macrophage polarization (production of NO, ROS and pro-inflammatory proteins) than geraniin. Urolithin A leads to an elevated autophagic flux in macrophages. Inhibition of autophagy in M1 (LPS) macrophages overcomes the suppressed nuclear translocation of p65 (NF-kB; nuclear factor kB), the reduced expression of pro-inflammatory genes as well as the diminished NO production brought about by urolithin A. The increased autophagic flux is furthermore associated with impaired Akt/mTOR (mammalian target of rapamycin) signaling in urolithin A-treated macrophages.

CONCLUSIONS AND GENERAL SIGNIFICANCE

Intestinal metabolization may boost the potential health benefit of widely consumed dietary ellagitannins, as suggested by side by side comparison of geraniin and urolithin A in M1(LPS) macrophages. Increased activity of the autophagic cellular recycling machinery aids the anti-inflammatory bioactivity of urolithin A.