Targeting AMPK, mTOR and β-Catenin by Combined Metformin and Aspirin Therapy in HCC: An Appraisal in Egyptian HCC Patients

Aspirin in Cancer Therapy: Pharmacology and Nanotechnology Advances

Aspirin, a non-steroidal anti-inflammatory drug (NSAID), has garnered significant attention for its anti-cancer potential. This review explores the pharmacological properties, chemical dynamics, and evolving therapeutic applications of aspirin, with an emphasis on its integration into advanced cancer therapies. Aspirin demonstrates broad-spectrum efficacy across diverse cancer types by modulating signaling pathways such as COX-dependent and COX-independent mechanisms, including Wnt, NF-κB, β-catenin/TCF, and IL-6/STAT3. Recent advancements highlight the role of nanotechnology in enhancing aspirin's targeted delivery, therapeutic effectiveness, and patient outcomes. Nanoparticle-based formulations, including liposomes, solid lipid nanoparticles, and mesoporous silica nanoparticles, offer improved solubility, stability, and bioavailability, enabling controlled drug release and tumor-specific targeting. These innovations reduce systemic toxicity and enhance therapeutic effects, paving the way for aspirin's integration into personalized cancer treatments. Ongoing clinical studies reinforce its safety profile, underscoring aspirin's role in cancer pharmacotherapy. This review calls for continued research into aspirin's repurposing in combination therapies and novel delivery systems to maximize its therapeutic potential.

Multi-omics Insights into PDHA1 as a Predictive Biomarker for Prognosis, Immunotherapy Efficacy, and Drug Sensitivity in Hepatocellular Carcinoma

PDHA1 was associated with metabolic reprogramming in tumor progression. However, the clinical value of PDHA1, especially for prediction of drug sensitivity in hepatocellular carcinoma (HCC), has not been fully investigated. In this study, we found that PDHA1 expression was higher in HCC tissues compared to normal tissues and was correlated with poor prognosis in HCC patients. PDHA1 expression was mainly positively associated with immune cell infiltration using the TIMER, XCell, MCPCOUNTER, CIBERSORT, EPIC, and QUANTISEQ algorithms, which was validated by single-cell RNA-sequencing analysis. We also discovered that PDHA1 expression was correlated with six immune checkpoint-related genes. Univariate and multivariate Cox regression analyses revealed that PDHA1 expression was an independent prognostic indicator for HCC patients, and the nomogram incorporating PDHA1 expression exhibited excellent predictive capacity. Furthermore, PDHA1 expression was positively linked to the sensitivity of 5-fluorouracil, gemcitabine, paclitaxel, and sorafenib, and the molecular docking analysis demonstrated their excellent binding affinity.

Additive Cytotoxic and Colony-Formation Inhibitory Effects of Aspirin and Metformin on PI3KCA-Mutant Colorectal Cancer Cells

Human malignancies are one of the major health-related issues throughout the world and are anticipated to rise in the future. Despite huge investments made in anticancer drug development, limited success has been obtained and the average number of FDA approvals per year is declining. So, an increasing interest in drug repurposing exists. Metformin (MET) and aspirin (ASP) possess anticancer properties. This work aims to test the effect of these two drugs in combination on colorectal cancer (CRC) cells in vitro. The effects of MET and/or ASP on cell proliferation, viability, migratory ability, anchorage-independent growth ability (colony formation), and nutrient uptake were determined in two (HT-29 and Caco-2) human CRC cell lines. Individually, MET and ASP possessed antiproliferative, cytotoxic, and antimigratory effects and reduced colony formation in HT-29 cells (BRAF- and phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit α (PI3KCA)-mutant), although MET did not affect either 3H-deoxy-D-glucose or 14C-butyrate uptake and lactate production, and ASP caused only a small decrease in 14C-butyrate uptake. Moreover, in these cells, the combination of MET and ASP resulted in a tendency to an increase in the cytotoxic effect and in a potentiation of the inhibitory effect on colony formation, although no additive antiproliferative and antimigratory effects, and no effect on nutrient uptake and lactate production were observed. In contrast, MET and ASP, both individually and in combination, were almost devoid of effects on Caco-2 cells (BRAF- and PI3KCA-wild type). We suggest that inhibition of PI3K is the common mechanism involved in the anti-CRC effect of both MET, ASP and their combination and, therefore, that the combination of MET + ASP may especially benefit PI3KCA-mutant CRC cases, which currently have a poor prognostic.

Leveraging metformin to combat hepatocellular carcinoma: its therapeutic promise against hepatitis viral infections

Hepatocellular carcinoma (HCC) is categorized among the most common primary malignant liver cancer and a primary global cause of death from cancer. HCC tends to affect males 2-4 times more than females in many nations. The main factors that raise the incidence of HCC are chronic liver diseases, hepatotropic viruses like hepatitis B (HBV) and C (HCV), non-alcoholic fatty liver disease, exposure to toxins like aflatoxin, and non-alcoholic steatohepatitis (NASH). Among these, hepatitis B and C are the most prevalent causes of chronic hepatitis globally. Metformin, which is made from a naturally occurring compound called galegine, derived from the plant Galega officinalis (G. officinalis ), has been found to exhibit antitumor effects in a wide range of malignancies, including HCC. In fact, compared to patients on sulphonylureas or insulin, studies have demonstrated that metformin treatment significantly lowers the risk of HCC in patients with chronic liver disease. This article will first describe the molecular mechanism of hepatitis B and C viruses in the development of HCC. Then, we will provide detailed explanations about metformin, followed by a discussion of the association between metformin and hepatocellular carcinoma caused by the viruses mentioned above.

Analysis of differential membrane proteins related to matrix stiffness-mediated metformin resistance in hepatocellular carcinoma cells

BACKGROUND

Our previous work shows that increased matrix stiffness not only alters malignant characteristics of hepatocellular carcinoma (HCC) cells, but also attenuates metformin efficacy in treating HCC cells. Here, we identified differential membrane proteins related to matrix stiffness-mediated metformin resistance for better understand therapeutic resistance of metformin in HCC.

METHODS

Differential membrane proteins in HCC cells grown on different stiffness substrates before and after metformin intervention were screened and identified using isobaric tags for relative and absolute quantification (iTRAQ) labeling coupled with the liquid chromatography-tandem mass spectrometry (LC-MS/MS), then bioinformatic analysis were applied to determine candidate membrane protein and their possible signaling pathway.

RESULTS

A total of 5159 proteins were identified and 354 differential membrane proteins and membrane associated proteins, which might be associated with matrix stiffness-mediated metformin resistance were discovered. Then 94 candidate membrane proteins including 21 up-regulated protein molecules and 73 down-regulated protein molecules were further obtained. Some of them such as Annexin A2 (ANXA2), Filamin-A (FLNA), Moesin (MSN), Myosin-9 (MYH9), Elongation factor 2 (eEF2), and Tax1 binding Protein 3 (TAX1BP3) were selected for further validation. Their expressions were all downregulated in HCC cells grown on different stiffness substrates after metformin intervention. More importantly, the degree of decrease was obviously weakened on the higher stiffness substrate compared with that on the lower stiffness substrate, indicating that these candidate membrane proteins might contribute to matrix stiffness-mediated metformin resistance in HCC.

CONCLUSIONS

There was an obvious change in membrane proteins in matrix stiffness-mediated metformin resistance in HCC cells. Six candidate membrane proteins may reflect the response of HCC cells under high stiffness stimulation to metformin intervention, which deserve to be investigated in the future.

The mechanism of ferroptosis in early brain injury after subarachnoid hemorrhage

Subarachnoid hemorrhage (SAH) is a cerebrovascular accident with an acute onset, severe disease characteristics, and poor prognosis. Within 72 hours after the occurrence of SAH, a sequence of pathological changes occur in the body including blood-brain barrier breakdown, cerebral edema, and reduced cerebrovascular flow that are defined as early brain injury (EBI), and it has been demonstrated that EBI exhibits an obvious correlation with poor prognosis. Ferroptosis is a novel programmed cell death mode. Ferroptosis is induced by the iron-dependent accumulation of lipid peroxides and reactive oxygen species (ROS). Ferroptosis involves abnormal iron metabolism, glutathione depletion, and lipid peroxidation. Recent study revealed that ferroptosis is involved in EBI and is significantly correlated with poor prognosis. With the gradual realization of the importance of ferroptosis, an increasing number of studies have been conducted to examine this process. This review summarizes the latest work in this field and tracks current research progress. We focused on iron metabolism, lipid metabolism, reduction systems centered on the GSH/GPX4 system, other newly discovered GSH/GPX4-independent antioxidant systems, and their related targets in the context of early brain injury. Additionally, we examined certain ferroptosis regulatory mechanisms that have been studied in other fields but not in SAH. A link between death and oxidative stress has been described. Additionally, we highlight the future research direction of ferroptosis in EBI of SAH, and this provides new ideas for follow-up research.

AMPK/mTOR-mediated therapeutic effect of metformin on myocardial ischaemia reperfusion injury in diabetic rat

BACKGROUND

The autophagy associated signalling pathways such as AMPK/mTOR previously were suggested to play a crucial role in protecting from ischaemia-reperfusion injury (IRI). The objective of this study was to evaluate the effect of metformin (DMBG) on autophagy during myocardial IRI with diabetes mellitus (DM).

METHODS

The DM rat model was established using streptozocin, and further induced ischaemia model via transitory ligation of the left anterior coronary artery and following reperfusion. The model rats were treated with 400 mg/kg/day DMBG for 1 week. Autophagosomes were investigated using transmission electron microscopy. Autophagy-associated signalling pathways were detected by western blot.

RESULTS

The myocardial infarct size was shown to significantly increase in the DM rats exposed to IRI compared to negative control, but decrease in DMBG treated. The mature autophagosomes were elevated in infarction and marginal zones of DM + IRI + DMBG compared to DM + IRI. Furthermore, the increasing protein levels of LC3-II, BECLIN 1, autophagy related 5 (ATG5) and AMP-activated protein kinase suggested activated autophagy-associated intracellular signalling AMPK and mTOR pathways upon DMBG treated.

CONCLUSIONS

Taken together, the outcomes determinate a novel mechanism that DMBG could activate autophagy process to provide a cardio-protective effect against DM induced myocardial IRI.

Magnolol-loaded Cholesteryl Biguanide Conjugate Hydrochloride Nanoparticles for Triple-negative Breast Cancer Therapy

The potential of combination therapy using nanoparticle delivery systems in improving triple-negative breast cancer treatment efficacy remains to be explored. Here, we report a novel nanoparticle system using a cholesterol biguanide conjugate hydrochloride (CBH) as both a drug and carrier to load magnolol (MAG). Poly(ethylene glycol)-poly(lactic-co-glycolic acid) (mPEG-PLGA) and aminoethyl anisamide-poly(ethylene glycol)-poly(lactic-co-glycolic acid) (AEAA-PEG-PLGA) were added to form nanoparticles. Nanoparticles accumulated most in tumor tissues when the weight ratio of AEAA-PEG-PLGA to mPEG-PLGA was 4:1. MAG and CBH exerted a synergistic inhibitory effect on 4T1 cells. An in vitro study showed that nanoparticles displayed the highest tumor cell uptake rate, highest apoptosis rate, and strongest inhibitory effect on tumor cell migration and monoclonal formation. CBH might promote nanoparticle uptake by cells and lysosomal escape. After intravenous administration to mice with 4T1 breast tumors in situ, the nanoparticles inhibited tumor growth without obvious toxicity. Western blot results showed that nanoparticles altered the levels of p53, p-AKT, and p-AMPK in the tumor tissue. Moreover, cell apoptosis was found in the same area of H&E-stained and TUNEL-stained tumors treated with the nanoparticles. Collectively, this nanoparticle system provides a novel combination drug delivery strategy for treating triple-negative breast cancer.

Crosstalk of hypothalamic chemerin, histamine, and AMPK in diet-and olanzapine-induced obesity in rats

AIM

Contradiction overwhelms chemerin link to feeding behavior. Neither the chemerin central role on appetite regulation nor its relation to hypothalamic histamine and AMPK is verified.

MAIN METHODS

Food intake, body weight and hypothalamic biochemical changes were assessed after a single intra-cerebroventricular or intraperitoneal injection (ip) (1 μg/kg or 16 μg/kg, respectively) or chronic ip administration (8 μg/kg/day) of chemerin for 14 or 28 days. Hypothalamic neurobiochemical changes in chemerin/histamine/AMPK induced by either 8-week high fat diet (HFD) or food restriction were also investigated. To confirm chemerin-histamine crosstalk, these neurobiochemical changes were assessed under settings of H1-receptor agonism and/or antagonism by betahistine and/or olanzapine, respectively for 3 weeks.

KEY FINDINGS

Chemerin-injected rats exhibited anorexigenic behavior in both acute and chronic studies that was associated with a decreased AMPK activity in the arcuate nucleus (ARC). However, with long-term administration, chemerin anorexigenic effect gradually ceased. Contrarily to food restriction, 8-week HFD increased ARC expression of chemerin and its receptor CMKLR1, reducing food intake via an interplay of H1-receptors and AMPK activity. Blockage of H1-receptors by olanzapine disrupted chemerin signaling pathway with an increased AMPK activity, augmenting food intake. These changes were reversed to normal by betahistine coadministration.

SIGNIFICANCE

Chemerin is an anorexigenic adipokine, whose dysregulation is implicated in diet, and olanzapine-induced obesity through a histamine/AMPK axis in the ARC. Hypothalamic chemerin/CMKLR1 expression is a dynamic time-dependent response to changes in body weight and/or food intake. Targeting chemerin as a novel therapeutic approach against antipsychotic- or diet-induced obesity is worth to be further delineated.

Systematic review with meta-analysis: The effects of non-steroidal anti-inflammatory drugs and anti-platelet therapy on the incidence and recurrence of hepatocellular carcinoma

BACKGROUND

Chemoprevention with NSAIDs, including aspirin, and anti-platelet therapy (APT), has been suggested to reduce the incidence and recurrence of hepatocellular carcinoma (HCC).

AIM

To determine by meta-analysis whether NSAIDs and APT use affected HCC incidence, HCC recurrence and liver-related mortality in at-risk populations with chronic liver disease.

METHOD

Electronic databases including Pubmed, Scopus, Medline, Embase and Cochrane Library were searched (from inception to 31 May 2021) for eligible studies evaluating the impacts of NSAID or APT use on HCC incidence, recurrence and mortality. Data on HCC incidence, recurrence, liver-related mortality or bleeding complications had to be available. Studies were included if they evaluated adults with hepatitis B virus (HBV), hepatitis C virus (HCV), alcohol-related liver disease (ALD) or nonalcoholic steatohepatitis that were administered at least one NSAID or APT for a defined period of time and were followed for at least 6 months. The primary outcome was HCC incidence. Secondary outcomes included: HCC recurrence, liver-related mortality and bleeding complications. Data were pooled using a random effects model with hazard ratios (HRs) or odds ratio (OR), and 95% confidence intervals (CIs) presented.

RESULTS

Of 3773 articles screened, 19 studies were included, with a total of 147 283 participants. Aspirin use reduced the risk of HCC incidence (HR: 0.51, 95% CI: 0.36-0.72); and improved liver-related mortality (OR: 0.32, 95% CI: 0.15-0.70), with a small increased risk of gastrointestinal bleeding events (OR: 1.32, 95% CI: 1.08-1.94). With respect to HCC recurrence following treatment, analysis of all aspirin and NSAID treatment (including; aspirin only; non-aspirin NSAIDs only; and combination NSAIDs groups) was associated with a decreased risk of HCC recurrence (HR: 0.80, 95% CI: 0.75-0.86). By stratified analysis, only the non-aspirin NSAID group showed significant risk reduction (HR: 0.73, 95% CI: 0.63-0.84).

CONCLUSION

The study supports the use of aspirin in at-risk individuals to reduce the incidence of HCC and liver-related mortality. HCC recurrence following treatment was lower with NSAID treatment.

Manuka honey enhanced sensitivity of HepG2, hepatocellular carcinoma cells, for Doxorubicin and induced apoptosis through inhibition of Wnt/β-catenin and ERK1/2

Background

Recently, there is increasing awareness focused on the identification of naturally occurring anticancer agents derived from natural products. Manuka honey (MH) has been recognized for its biological properties as antimicrobial, antioxidant, and anticancer properties. However, its antiproliferative mechanism in hepatocellular carcinoma is not investigated. The current study focused mainly on investigating the molecular mechanism and synergistic effect of anticancer properties of MH on Doxorubicin (DOX)-mediated apoptotic cell death, using two different p53 statuses (HepG2 and Hep3B) and one non-tumorigenic immortalized liver cell line.

Results

MH treatment showed a proliferative inhibitory effect on tested cells in a dose-dependent manner with IC₅₀ concentration of (6.92 ± 0.005%) and (18.62 ± 0.07%) for HepG2 and Hep3B cells, respectively, and induced dramatic morphological changes of Hep-G2 cells, which considered as characteristics feature of apoptosis induction after 48 h of treatment. Our results showed that MH or combined treatments induced higher cytotoxicity in p53-wild type, HepG2, than in p53-null, Hep3B, cells. Cytotoxicity was not observed in normal liver cells. Furthermore, the synergistic effect of MH and Dox on apoptosis was evidenced by increased annexin-V-positive cells and Sub-G1 cells in both tested cell lines with a significant increase in the percentage of Hep-G2 cells at late apoptosis as confirmed by the flow cytometric analysis. Consistently, the proteolytic activities of caspase-3 and the degradation of poly (ADP-ribose) polymerase were also higher in the combined treatment which in turn accompanied by significant inhibitory effects of pERK1/2, mTOR, S6K, oncogenic β-catenin, and cyclin D1 after 48 h. In contrast, the MH or combined treatment-induced apoptosis was accompanied by significantly upregulated expression of proapoptotic Bax protein and downregulated expression of anti-apoptotic Bcl-2 protein after 48 h.

Conclusions

Our data showed a synergistic inhibitory effect of MH on DOX-mediated apoptotic cell death in HCC cells. To our knowledge, the present study provides the first report on the anticancer activity of MH and its combined treatment with DOX on HCC cell lines, introducing MH as a promising natural and nontoxic anticancer compound.

Extracellular vesicles miRNA-21: a potential therapeutic tool in premature ovarian dysfunction

Chemotherapy induces an irreversible premature ovarian dysfunction (POD). Amniotic fluid mesenchymal stem cells (AFMSCs) can rescue fertility; however, the notion that stem cells can rejuvenate follicles is highly controversial due to the predetermined ovarian reserve. This study aims to isolate AFMSC-derived extracellular vesicles (EVs) and investigate their abundancy for the anti-apoptotic miRNA-21 as a means of ovarian restoration. Female rats were divided into healthy controls and POD-induced groups. The POD induced groups were subdivided into three groups according to the therapies they received: placebo-treated POD, AFMSC and EVs groups. Rats were assessed for serum anti-Müllerian hormone (AMH) levels, ovarian caspase 3 and PTEN protein levels in the ovarian lysate. Total follicular counts (TFCs) were estimated from stained ovarian sections. Functional recovery was investigated through daily vaginal smears and mating trials. In vitro chemical transfection of the AFMSCs with selective miRNA-21 mimics/inhibitors followed by isolation of EVs for therapy was conducted in two additional groups. At the interval points studied, treatment with AFMSCs and EVs equally restored TFC, AMH levels, regular estrous cycles and fruitful conception, while it both diminished caspase 3 and PTEN levels. EVs carrying miRNA-21 mimics recapitulated the short-term effects. Placebo-treated POD or EVs carrying miRNA-21 inhibitors showed augmented ovarian follicular damage demonstrated the low AMH levels, TFC and high levels of PTEN and caspase 3. miRNA-21 allowed regeneration by modulating PTEN and caspase 3 apoptotic pathways. Our findings exemplify that EVs could serve as an innovative cell-free therapeutic tool functioning through their miRNA content and that miRNA-21 has a chief regenerative role through modulating PTEN and caspase 3 apoptotic pathways.

Melanotic neuroectodermal tumor of infancy successfully treated with metformin: A case report

RATIONALE

Melanotic neuroectodermal tumor of infancy (MNTI) is a rare tumor originated from neural crest cells with the potential for recurrence and metastasis. The peak age for the disease is during the first year after birth. The current therapy is primarily surgery. The patient reported here is the first case of MNTI treated with metformin.

PATIENT CONCERNS

A case of a 4-month-old infant with a history of swelling in the mouth for 1 month.

DIAGNOSIS

The tumor was diagnosed using radiology, pathology, and immunohistochemistry, and it was performed with complete surgical resection. Unfortunately, the tumor recurred 3 months after surgery.

INTERVENTIONS

We prescribed metformin for the infant.

OUTCOMES

Currently, after 9 months of treatment, the tumor is well controlled without apparent side effects.

LESSONS

The case presented suggested that metformin may be an underlying therapy for MNTI.

Novel combination of celecoxib and metformin improves the antitumor effect by inhibiting the growth of Hepatocellular Carcinoma

Objective: To explore the effect of COX-2 inhibitor celecoxib in combination with metformin on the prevention of Hepatocellular carcinoma (HCC) and the mechanisms involved.

Methods: HCC cell lines and an HCC rat model were treated with celecoxib, metformin or a combination of both. Cell viability and tumor formation were measured.

Results:In vitro and in vivo studies showed that treatment with a combination of celecoxib and metformin inhibited proliferation of HCC to a greater extent than either treatment alone, by reducing the phosphorylation of MTOR.

Conclusion: The study suggested that celecoxib combined with metformin would be more effective for the preventing occurrence of HCC than either treatment alone and this combination of therapy is worthy of further study.

Metformin Induces Autophagy via the AMPK-mTOR Signaling Pathway in Human Hepatocellular Carcinoma Cells

Background

Metformin may exert the anticancer effect on multiple types of cancers and some potential mechanisms have been suggested. Our study was designed to determine the effect of metformin on the cell autophagy and autophagic flux via the AMPK-mTOR signaling pathway in human hepatocellular carcinoma (HCC) cells.

Methods

MHCC97H and HepG2 cell lines were cultured and treated without and with metformin at various concentrations (2, 5, 10 and 20 mM) for 48 h. Then, 10 mM was determined as the optimal concentration and the HCC cells were treated with metformin for 12, 24, 48, and 72 h. MTT assay was used to assess the cell viability and Western blotting was used to determine the expression of proteins (LC3-II, p62, phospho-AMPKα, phospho-mTOR, mTOR, phospho-p70 S6 Kinase, p70 S6 Kinase, PARP1, Caspase-9 and Caspase-3). Autophagy inhibitor 3-methyladenine, EGFP-LC3 and mCherry-GFP-LC3B plasmid transfection were used for further study.

Results

Metformin inhibited significantly the viability of MHCC97H and HepG2 cells in a dose- and time-dependent manner. For the apoptotic properties, activation of Caspase-9 and Caspase-3 and PARP cleavage were not observed after treatment with metformin. MHCC97H cells were transfected with a EGFP-LC3 plasmid and treatment with metformin could lead to the increased level of LC3-II and decreased level of p62. In metformin-induced autophagy, AMPK expression was activated, and the phosphorylation levels of mTOR and p70 S6 Kinase were inhibited. Metformin treatment and mCherry-GFP-LC3B plasmid transfection showed that metformin could induce the autophagic flux. 3-Methyladenine (3-MA) partly abolished this effect.

Conclusion

Metformin could induce the autophagy, autophagic flux, and activate the AMPK-mTOR signaling pathway in human HCC cells.

Combination of aloin and metformin enhances the antitumor effect by inhibiting the growth and invasion and inducing apoptosis and autophagy in hepatocellular carcinoma through PI3K/AKT/mTOR pathway

Hepatocellular carcinoma (HCC) is a devastating and highly metastatic cancer worldwide. Metformin (MET) is the priority drug for treatment of type 2 diabetes; however, it possesses multiple biological effects like anticancer and hepatoprotective activity. Herein, we examined the effects of aloin (barbaloin) and MET as well as combination treatment in HCC cell line in vitro and in vivo. As a result, aloin and MET alone exhibited inhibitory effects on proliferation and invasion of HepG2 and Bel-7402 cells. Specially, combination treatment of aloin and MET showed enhanced inhibitory effects in vitro. Aloin and MET alone induced apoptosis and autophagy in vitro. Similarly, aloin and MET cooperated to promote apoptosis and autophagy in HepG2 and Bel-7402 cells. In the HepG2 xenograft models, aloin in combination with MET confine tumor growth and facilitate apoptosis and autophagy. Both the in vitro and in vivo results showed that aloin and MET alone as well as combination treatment activated the PI3K/AKT/mTOR pathway. Overall, our research demonstrated that the concomitant treatment with aloin and MET enhances the antitumor effect by inhibiting the growth and invasion as well as inducing apoptosis and autophagy in HCC through PI3K/AKT/mTOR pathway.

Suppressive effects of metformin on colorectal adenoma incidence and malignant progression

BACKGROUND

The linear progression from normal colonic epithelium to adenoma initiation, carcinoma transformation and metastasis is considered the classical model of colorectal cancer (CRC) development. Although metformin has been extensively reported to be negatively related to cancer incidence, the effect of metformin on CRC development remains unclear. We aimed to evaluate the role of metformin in the entire CRC linear progression.

METHODS

Systematic searches and data extraction were performed in the PubMed, Embase, and Cochrane Library databases on Jan 31, 2019. The combined relative ratios (RRs) of colorectal tumor incidence and the hazard ratios (HRs) of overall survival (OS) and cancer-specific survival (CSS) were evaluated by a random-effects model. Then, the effects of metformin were further assessed through stratified analyses by population, medication duration and dosage, dose-response analysis and comparison with other antidiabetic agents.

RESULTS

A total of 50 studies consisting of 238,540 cases of diabetes mellitus (DM) were included in this study. Metformin use was negatively associated with the incidence of colorectal adenoma (RR: 0.75, 95% CI: 0.65-0.86) and CRC (RR: 0.73, 95% CI: 0.58-0.90). Moreover, CRC patients benefited from metformin in terms of both OS (HR: 0.73, 95% Cl: 0.63-0.84) and CSS (HR: 0.60, 95% Cl: 0.50-0.73). Stratified analyses suggested that a long duration of high-dose metformin (RR: 0.52, 95% Cl: 0.36-0.83) was more effective than a short duration in Asian populations against colorectal adenoma (RR: 0.66, 95% Cl: 056-0.70) and CRC (RR: 0.45, 95% Cl: 0.29-0.70). Interestingly, metformin use decreased CRC risk in a dose-dependent manner (RR: 0.91, 95% CI: 0.87-0.95). In addition, the benefit of metformin on CRC was more significant than that of other antidiabetic agents, including insulin.

CONCLUSIONS

The use of metformin is associated with a lower incidence of adenoma and CRC and a better prognosis, especially in Asian populations.

Drp1 and RB interaction to mediate mitochondria-dependent necroptosis induced by cadmium in hepatocytes

Mitochondrial quality control (MQC) is implicated in cell death induced by heavy metal pollutants. Dynamin-related protein 1 (Drp1) regulates mitochondrial fission, which is an important part of MQC. Retinoblastoma (RB) protein can regulate MQC in a transcription-independent manner. Necroptosis plays a critical role in hepatic pathologies such as inflammatory, infectious, and xenobiotics-induced injury and diseases. We aimed to explore the role and mechanism of Drp1 interaction with RB in hepatocyte's necroptosis caused by cadmium (Cd). CdCl₂ was employed to expose to Institute of Cancer Research (ICR) mice and human hepatic L02 cells. CdCl₂ exposure induced necroptosis and hepatic injury both in vivo and in vitro. Moreover, Drp1 and RB protein were up-regulated and translocated to mitochondria in CdCl₂-exposed hepatocytes. Inhibition of Drp1 with siRNA (siDNM1L) or inhibitors not only suppressed the RB expression and its mitochondrial translocation, but also alleviated MQC disorder, necroptosis, and hepatotoxicity caused by CdCl₂. Moreover, blocking Drp1 with metformin rescued necroptosis and hepatic injury triggered by CdCl₂. RB was proved to directly interact with Drp1 at mitochondria to form a complex which then bound to receptor interaction protein kinase (RIPK3) and enhanced the formation of necrosome after CdCl₂ exposure. In summary, we found a new molecular mechanism of regulated cell death that Drp1 interacted with RB and promoted them mitochondrial translocation to mediate necroptosis and hepatic injury in hepatocytes induced by Cd-exposure. The mitochondrial Drp1-RB axis would be a novel target for the protection cells from xenobiotics triggering hepatic injury and diseases involved in necroptosis.

Role of p53 Family Proteins in Metformin Anti-Cancer Activities

Metformin has been used as therapy for type 2 diabetes for many years. Clinical and basic evidence as indicated that metformin has anti-cancer activities. It has been well-established that metformin activates AMP-activated protein kinase (AMPK), which in turn regulates energy homeostasis. However, the mechanistic aspects of metformin anti-cancer activity remain elusive. p53 family proteins, including p53, p63 and p73, have diverse biological functions, including regulation of cell growth, survival, development, senescence and aging. In this review, we highlight the evidence and mechanisms by which metformin inhibits cancer cell survival and tumor growth. We also aimed to discuss the role of p53 family proteins in metformin-mediated suppression of cancer growth and survival.

MicroRNA-1271 functions as a potential tumor suppressor in hepatitis B virus-associated hepatocellular carcinoma through the AMPK signaling pathway by binding to CCNA1

Hepatocellular carcinoma (HCC) is mainly associated with hepatitis B virus (HBV) infection and characterized by metastasizing and infiltrating adjacent and distant tissues. Notably, microRNA-1271 (miR-1271) is a tumor suppressor in various cancers. Therefore, we evaluate the ability of miR-1271 to influence cell proliferation, migration, invasion, and apoptosis in HBV-associated HCC through the Adenosine monophosphate-activated protein kinase (AMPK) signaling pathway via targeting CCNA1. HBV-associated HCC and adjacent normal tissues were collected to identify the expression of miR-1271 and CCNA1. To verify the relationship between miR-1271 and CCNA1, we used bioinformatics prediction and the dual-luciferase reporter gene assay. The effects of miR-1271 on HBV-associated HCC cell behaviors were investigated by treatment of the miR-1271 mimic, the miR-1271 inhibitor, or small interfering RNA against CCNA1. The HBV-DNA quantitative assay, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromid assay, scratch test, transwell assay, and flow cytometry were used to detect HBV-DNA replication, cell proliferation, invasion, migration, and apoptosis. MiR-1271 showed a low expression, whereas CCNA1 showed a high expression in HBV-associated HCC tissues. We identified that miR-1271 targeted and negatively regulated CCNA1. Upregulated miR-1271 and downregulated CCNA1 inhibited the HBV-associated HCC cell HBV-DNA replication, proliferation, migration, and invasion, while accelerating apoptosis by activating the AMPK signaling pathway. MiR-1271 promotes the activation of the AMPK signaling pathway by binding to CCNA1, whereby miR-1271 suppresses HBV-associated HCC progression. This study points to a potential therapeutic approach of downregulation of miR-1271 in HBV-associated HCC treatment.

Ferroptosis, a new form of cell death: opportunities and challenges in cancer

Ferroptosis is a novel type of cell death with distinct properties and recognizing functions involved in physical conditions or various diseases including cancers. The fast-growing studies of ferroptosis in cancer have boosted a perspective for its usage in cancer therapeutics. Here, we review the current findings of ferroptosis regulation and especially focus on the function of ncRNAs in mediating the process of cell ferroptotic death and on how ferroptosis was in relation to other regulated cell deaths. Aberrant ferroptosis in diverse cancer types and tissues were summarized, and we elaborated recent data about the novel actors of some “conventional” drugs or natural compounds as ferroptosis inducers in cancer. Finally, we deliberate future orientation for ferroptosis in cancer cells and current unsettled issues, which may forward the speed of clinical use of ferroptosis induction in cancer treatment.

Pre-clinical effects of metformin and aspirin on the cell lines of different breast cancer subtypes

Background Breast cancer is highly prevalent among women worldwide. It is classified into three main subtypes: estrogen receptor positive (ER+), human epidermal growth factor receptor 2 positive (HER2+), and triple negative breast cancer (TNBC). This study has evaluated the effects of aspirin and metformin, isolated or in a combination, in breast cancer cells of the different subtypes. Methods The breast cancer cell lines MCF-7, MDA-MB-231, and SK-BR-3 were treated with aspirin and/or metformin (0.01 mM - 10 mM); functional in vitro assays were performed. The interactions with the estrogen receptors (ER) were evaluated in silico. Results Metformin (2.5, 5 and 10 mM) altered the morphology and reduced the viability and migration of the ER+ cell line MCF-7, whereas aspirin triggered this effect only at 10 mM. A synergistic effect for the combination of metformin and aspirin (2.5, 5 or 10 mM each) was observed in the TNBC cell subtype MDA-MB-231, according to the evaluation of its viability and colony formation. Partial inhibitory effects were observed for either of the drugs in the HER2+ cell subtype SK-BR-3. The effects of metformin and aspirin partly relied on cyclooxygenase-2 (COX-2) upregulation, without the production of lipoxins. In silico, metformin and aspirin bound to the ERα receptor with the same energy. Conclusion We have provided novel evidence on the mechanisms of action of aspirin and metformin in breast cancer cells, showing favorable outcomes for these drugs in the ER+ and TNBC subtypes.