Targeting PI3K/Akt/mTOR signaling pathway by polyphenols: Implication for cancer therapy

Immunocytochemical examination of Akt, mTOR, and Pax-2 for endometrial carcinoma through thin-layer endometrial cytology

Objective

This study aimed to detect the expression of Akt, mTOR, and Pax-2 in differing endometrial tissue/cells, together with assessment of such molecular markers for improving accuracy within endometrial cytology screening for endometrial cancer (EC).

Methods

Overall, 92 hysteroscopy cases were included. This cohort comprised 32 endometrial carcinoma patients, 30 benign lesion patients, and 30 cases with normal endometrium. Endometrial cells were collected before hysteroscopy, for immunohistochemical (IHC) and immunocytochemical (ICC) detection of Akt, mTOR, and Pax-2. Expression levels were evaluated by semi-quantitative method, and ROC curves (Receiver Operating Characteristic Curve) were drawn to evaluate the application importance for all three biomarkers for EC diagnostics.

Results

IHC expression of Akt, mTOR, and Pax-2 was positively correlated with ICC expression within the endometrial carcinoma cohort, benign lesion cohort, and normal cohort. Using IHC and ICC, Akt/mTOR-marked upregulation was observed within the EC cohort, compared to all other cohorts. Pax-2 was also markedly upregulated within normal/benign lesion cohorts in comparison to the EC cohort (p < 0.01). The sensitivity and specificity of ICC was 73.33 and 91.53%, respectively, when Akt ≥ 190 was used as the diagnostic index for EC. When mTOR ≥ 255 was used as the diagnostic index for EC, such parameters were 84.38 and 95.00%, respectively. When Pax-2 ≤ 165 was used as the diagnostic index for EC, such parameters were 96.67 and 80.00%, respectively.

Conclusion

This investigation probed varying threshold levels pertaining to Akt, mTOR, and Pax-2, consequently assisting in endometrial lesion-type identification. IHC within ECT (endometrial cytology test) analyses for Akt, mTOR, and Pax-2 could enhance the capacity for diagnosing EC/pre-malignant lesions.

Pyrazolopyrimidines: A Promising Frontier in Cancer Treatment-Reviewing Their Potential as Inhibitors of Serine/Threonine Kinases

Pyrazolopyrimidine derivatives have emerged as potent inhibitors targeting a broad spectrum of kinases, particularly serine/threonine kinases (STK). This review provides a comprehensive overview of the structural modifications and pharmacological relevance of pyrazolopyrimidine compounds in the realm of kinase inhibition. Specifically, the focus is placed on their inhibitory action against STK, key players in cell signaling and potential therapeutic targets in various diseases, especially cancer. The structure-activity relationship (SAR) of these derivatives highlights the importance of specific substituents in enhancing inhibitory activity, and pyrazolopyrimidine derivatives have shown promising inhibitory activity against certain STK. Challenges remain, including issues related to drug resistance, off-target effects, and potential toxicity. Future research is geared toward designing more selective derivatives with improved pharmacokinetic properties and reduced side effects.

The Role of Pomegranate (Punica granatum) in Cancer Prevention and Treatment: Modulating Signaling Pathways From Inflammation to Metastasis

Punica granatum, commonly known as pomegranate, is a traditional medicinal agent owing to its antiquity. The scientific literature has shown that pomegranate extracts exhibit favorable modulation of diverse signaling pathways. These pathways encompass those implicated in inflammation, angiogenesis, hyperproliferation, cellular transformation, tumorigenesis initiation, and ultimately, a reduction in advanced metastasis and tumorigenesis. Pomegranate extracts in this context can be attributed to their high polyphenol content, which has been observed to possess inhibitory properties toward specific signaling pathways associated with cancer. As a formidable pathology, cancer is the most significant cause of death worldwide after cardiovascular disease. The annual incidence of cancer-related mortality has increased progressively. Modifying one's dietary patterns, engaging in regular physical exercise, and maintaining an optimal body mass index are three straightforward measures that an individual may undertake to mitigate their susceptibility to cancer. Incorporating diverse vegetables and fruits into one's dietary regimen exhibits promising potential for preventing a minimum of 20% cancer incidence and approximately 200,000 cancer-related mortalities annually. Vegetables and fruits contain high levels of minerals and phytochemicals, which help alleviate and prevent the harmful effects of cancer. These substances are safe and exhibit minimal toxicity in biological systems. Furthermore, they exhibit antioxidant properties and have garnered extensive approval for their use as nutritional supplements. Pomegranates are used in ancient cultures to prevent and treat various diseases. Extensive research on pomegranate extract, fruit, oil, and juice has revealed promising findings regarding their potential anti-proliferative, anti-tumorigenic, and anti-inflammatory properties through the modification of various signaling pathways related to cancer, thus demonstrating their potential as drugs to prevent and treat cancer. Emerging research indicates that pomegranate can potentially prevent and treat different cancers, including prostate, bladder, breast, skin, lung, and colon cancer.

The effect and mechanism of atorvastatin regulating PI3K-Akt-mTOR pathway on radiosensitivity of hepatocellular carcinoma cells

Radiation therapy is an important method to treat liver cancer, but because of the strong DNA repair ability of liver cancer cells, even after receiving high doses of radiation still can not get satisfactory results. Atorvastatin (ATO) is a lipophilic and tissue-selective inhibitor of HMG-CoA reductase whose anticancer effects have been validated in various cells, but its effect on the radiation sensitivity of hepatocellular carcinoma cells remains unclear. Therefore, Therefore, this study explored the radiosensitivity of ATO and its possible mechanism by pretreating HepG2 with ATO and collecting HepG2 cells after irradiation. It was found that atorvastatin can not only affect the survival of liver cancer cells when used alone, but also enhance the radiation sensitivity of HepG2 cells. The study found that ATO significantly exacerbated the inhibitory effects of IR on the growth, proliferation, and migration of HepG2 cells. Measurement of ROS, SOD, GPx, and MDA levels indicated that ATO enhanced IR-induced oxidative stress, further promoted the decrease of Mitochondrial Membrane Potential, increased the rate of apoptosis in HepG2, upregulating pro-apoptotic proteins Bax and Cleaved-Caspase 3, and downregulating anti-apoptotic proteins Bcl-2. Western blot analysis showed that the PI3K-Akt-mTOR pathway was inhibited, leading to the activation of cytotoxic autophagy in HepG2 and an increase in the expression of the LC-3II protein. In summary, ATO, in combination with IR, enhances the oxidative stress response of HepG2 induced by IR, promotes autophagy by inhibiting the PI3K-Akt-mTOR pathway, and thereby potentially enhances the radiosensitivity of HepG2 as a pharmacological intervention.

Oviductus Ranae Promotes Follicle Growth Through the PI3K/AKT Signaling Pathway In Vivo and In Vitro in Rat

The development status of follicles determines the menstrual cycle and estrogen levels, which is crucial to women's health. Oviductus Ranae is a natural product for both medicine and food, which has "estrogenic effect". However, few studies have systematically elaborated its mechanism of action. Hence, we hypothesize the "estrogen-like effects" of OR may stem from its positive influence on the growth and development of growing follicles in the ovaries. In this study, the effect of Oviductus Ranae (OR) on the growth and development of rat follicles and follicles cultured in vitro was investigated. The content of estrogen in rat serum and follicular culture medium in vitro was determined by radioimmunoassay, and the levels of PI3K-Akt signal pathway and FSHR expression in rat ovary and cultured follicles were detected by RT-PCR and Western Blot. The follicles at different developmental stages in rat ovaries were analyzed by H&E and TUNEL staining. Follicles cultured in a medium containing OR displayed a significant increase in diameter, and the E2 content in the medium was significantly increased. Moreover, Rats treated with OR showed significant increases in estradiol and progesterone levels. The number of antral follicles in the ovaries displayed a significant increase, while the percentage of atretic antral follicles and the total atretic follicles showed significant decreases. The relative expression levels of PI3K, Akt, and FSHR were significantly increased, while significantly decreased in that of PTEN In Vivo and In Vitro. OR may promote follicle growth through PI3K/ Akt pathway, exhibiting "estrogen-like effects".

Dietary interventions and tumor response to chemotherapy in breast cancer: A comprehensive review of preclinical and clinical data

BACKGROUND & AIMS

Optimizing treatment efficacy is still a critical part in advancing the treatment of breast cancer. Dietary interventions have drawn significant attention for their potential to increase tumor sensitivity, with a plethora of strategies evaluated both preclinically and clinically. The aim of this paper is to explore these strategies, ranging from entire dietary programs to specific supplements, for their potential to directly enhance tumor sensitivity and chemotherapy adherence.

METHODS

PubMed, Scopus, Embase and Web of Science databases were searched up to September 2023. In this comprehensive review, preclinical and clinical research on dietary interventions used in conjunction with chemotherapy for breast cancer was examined and synthesized, to identify potential causal mechanisms.

RESULTS

42 studies in total were identified and synthesized, 32 pre-clinical and 8 clinical studies.

CONCLUSION

Although a topic of intense interest, the heterogeneity in approaches has resulted in a large but minimally impactful evidence base, further complicated by a limited understanding of the mechanisms at play. This review highlights the areas for further research to increase opportunities for nutritional-based interventions as adjuvant to chemotherapy for breast cancer.

A bibliometric analysis of the application of the PI3K-AKT-mTOR signaling pathway in cancer

PI3K-AKT-mTOR plays as important role in the growth, metabolism, proliferation, and migration of cancer cells, and in apoptosis, autophagy, inflammation, and angiogenesis in cancer. In this study, the aim was to comprehensively review the current research landscape regarding the PI3K-AKT-mTOR pathway in cancer, using bibliometrics to analyze research hotspots, and provide ideas for future research directions. Literature published on the topic between January 2006 and May 2023 was retrieved from the Web of Science core database, and key information and a visualization map were analyzed using CiteSpace and VOSviewer. A total of 5800 articles from 95 countries/regions were collected, including from China and the USA. The number of publications on the topic increased year on year. The major research institution was the University of Texas MD Anderson Cancer Center. Oncotarget and Clinical Cancer Research were the most prevalent journals in the field. Of 26,621 authors, R Kurzrock published the most articles, and J Engelman was cited most frequently. "A549 cell," "first line treatment," "first in human phase I," and "inhibitor" were the keywords of emerging research hotspots. Inhibitors of the PI3K-AKT-mTOR pathway and their use in clinical therapeutic strategies for cancer were the main topics in the field, and future research should also focus on PI3K-AKT-mTOR pathway inhibitors. This study is the first to comprehensively summarize trends and development s in research into the PI3K-AKT-mTOR pathway in cancer. The information that was obtained clarified recent research frontiers and directions, providing references for scholars of cancer management.

Herbal Therapies for Cancer Treatment: A Review of Phytotherapeutic Efficacy

Natural products have proven to be promising anti-cancer agents due to their diverse chemical structures and bioactivity. This review examines their central role in cancer treatment, focusing on their mechanisms of action and therapeutic benefits. Medicinal plants contain bioactive compounds, such as flavonoids, alkaloids, terpenoids and polyphenols, which exhibit various anticancer properties. These compounds induce apoptosis, inhibit cell proliferation and cell cycle progression, interfere with microtubule formation, act on topoisomerase targets, inhibit angiogenesis, modulate key signaling pathways, improve the tumor microenvironment, reverse drug resistance and activate immune cells. Herbal anti-cancer drugs offer therapeutic advantages, particularly selective toxicity against cancer cells, reducing the adverse side effects associated with conventional chemotherapy. Recent studies and clinical trials highlight the benefits of herbal medicines in alleviating side effects, improving tolerance to chemotherapy and the occurrence of synergistic effects with conventional treatments. For example, the herbal medicine SH003 was found to be safe and potentially effective in the treatment of solid cancers, while Fucoidan showed anti-inflammatory properties that are beneficial for patients with advanced cancer. The current research landscape on herbal anticancer agents is extensive. Numerous studies and clinical trials are investigating their efficacy, safety and mechanisms of action in various cancers such as lung, prostate, breast and hepatocellular carcinoma. Promising developments include the polypharmacological approach, combination therapies, immunomodulation and the improvement of quality of life. However, there are still challenges in the development and use of natural products as anti-cancer drugs, such as the need for further research into their mechanisms of action, possible drug interactions and optimal dosage. Standardizing herbal extracts, improving bioavailability and delivery, and overcoming regulatory and acceptance hurdles are critical issues that need to be addressed. Nonetheless, the promising anticancer effects and therapeutic benefits of natural products warrant further investigation and development. Multidisciplinary collaboration is essential to advance herbal cancer therapy and integrate these agents into mainstream cancer treatment.

Combining In Vitro, In Vivo, and Network Pharmacology Assays to Identify Targets and Molecular Mechanisms of Spirulina-Derived Biomolecules against Breast Cancer

The current research employed an animal model of 7,12-dimethylbenz(a)anthracene (DMBA)-induced mammary gland carcinogenesis. The estrogen receptor-positive human breast adenocarcinoma cell line (MCF-7) was used for in vitro analysis. This was combined with a network pharmacology-based approach to assess the anticancer properties of Spirulina (SP) extract and understand its molecular mechanisms. The results showed that the administration of 1 g/kg of SP increased the antioxidant activity by raising levels of catalase (CAT) and superoxide dismutase (SOD), while decreasing the levels of malonaldehyde (MDA) and protein carbonyl. A histological examination revealed reduced tumor occurrence, decreased estrogen receptor expression, suppressed cell proliferation, and promoted apoptosis in SP protected animals. In addition, SP disrupted the G2/M phase of the MCF-7 cell cycle, inducing apoptosis and reactive oxygen species (ROS) accumulation. It also enhanced intrinsic apoptosis in MCF-7 cells by upregulating cytochrome c, Bax, caspase-8, caspase-9, and caspase-7 proteins, while downregulating Bcl-2 production. The main compounds identified in the LC-MS/MS study of SP were 7-hydroxycoumarin derivatives of cinnamic acid, hinokinin, valeric acid, and α-linolenic acid. These substances specifically targeted three important proteins: ERK1/2 MAPK, PI3K-protein kinase B (AKT), and the epidermal growth factor receptor (EGFR). Network analysis and molecular docking indicated a significant binding affinity between SP and these proteins. This was verified by Western blot analysis that revealed decreased protein levels of p-EGFR, p-ERK1/2, and p-AKT following SP administration. SP was finally reported to suppress MCF-7 cell growth and induce apoptosis by modulating the PI3K/AKT/EGFR and MAPK signaling pathways suggesting EGFR as a potential target of SP in breast cancer (BC) treatment.

Harnessing the capacity of phytochemicals to enhance immune checkpoint inhibitor therapy of cancers: A focus on brain malignancies

Brain cancers, particularly glioblastoma multiforme (GBM), are challenging health issues with frequent unmet aspects. Today, discovering safe and effective therapeutic modalities for brain tumors is among the top research interests. Immunotherapy is an emerging area of investigation in cancer treatment. Since immune checkpoints play fundamental roles in repressing anti-cancer immunity, diverse immune checkpoint inhibitors (ICIs) have been developed, and some monoclonal antibodies have been approved clinically for particular cancers; nevertheless, there are significant concerns regarding their efficacy and safety in brain tumors. Among the various tools to modify the immune checkpoints, phytochemicals show good effectiveness and excellent safety, making them suitable candidates for developing better ICIs. Phytochemicals regulate multiple immunological checkpoint-related signaling pathways in cancer biology; however, their efficacy for clinical cancer immunotherapy remains to be established. Here, we discussed the involvement of immune checkpoints in cancer pathology and summarized recent advancements in applying phytochemicals in modulating immune checkpoints in brain tumors to highlight the state-of-the-art and give constructive prospects for future research.

Metabolites of traditional Chinese medicine targeting PI3K/AKT signaling pathway for hypoglycemic effect in type 2 diabetes

Type 2 diabetes mellitus is a chronic metabolic disease characterized by insulin resistance, with high morbidity and mortality worldwide. Due to the tightly intertwined connection between the insulin resistance pathway and the PI3K/AKT signaling pathway, regulating the PI3K/AKT pathway and its associated targets is essential for hypoglycemia and the prevention of type 2 diabetes mellitus. In recent years, metabolites isolated from traditional Chinese medicine has received more attention and acceptance for its superior bioactivity, high safety, and fewer side effects. Meanwhile, numerous in vivo and in vitro studies have revealed that the metabolites present in traditional Chinese medicine possess better bioactivities in regulating the balance of glucose metabolism, ameliorating insulin resistance, and preventing type 2 diabetes mellitus via the PI3K/AKT signaling pathway. In this article, we reviewed the literature related to the metabolites of traditional Chinese medicine improving IR and possessing therapeutic potential for type 2 diabetes mellitus by targeting the PI3K/AKT signaling pathway, focusing on the hypoglycemic mechanism of the metabolites of traditional Chinese medicine in type 2 diabetes mellitus and elaborating on the significant role of the PI3K/AKT signaling pathway in type 2 diabetes mellitus. In order to provide reference for clinical prevention and treatment of type 2 diabetes mellitus.

Emodin ameliorates acute radiation proctitis in mice by regulating AKT/MAPK/NF-κB/VEGF pathways

BACKGROUND

Emodin, a natural anthraquinone derivative isolated from the roots of Rheum officinale Baill, has many pharmacological effects including anti-inflammatory, antioxidant, antiviral, antibacterial and anti-cancer. However, little is known about the effect of emodin on acute radiation proctitis (ARP). The present study was conducted to determine its effects and elucidate its mechanisms involving AKT/MAPK/NF-κB/VEGF pathways in ARP mice.

METHODS

Total 60 C57BL/6 mice were divided randomly into control group, ARP group, AKT inhibitor MK-2206 group, and different doses of emodin groups. ARP mice were induced by 27 Gy of 6 MV X-ray pelvic local irradiation. MK-2206 was given orally for 2 weeks on alternate days. Emodin was administered daily by oral gavage for 2 weeks. Subsequently, all mice were sacrificed on day 15. The rectal tissues were obtained for further tests. The general signs score and the pathological grade were used to evaluate the severity of ARP. The expression of NF-κB, VEGF and AQP1 were determined by immunohistochemistry and western blot. The expression of p-AKT, p-ERK, p-JNK, p-p38, Bcl-2 and Bax were assessed using western blot.

RESULTS

The worse general signs and damaged tissue structure of ARP mice were profoundly ameliorated by emodin. The expression of p-AKT, p-ERK, NF-κB, VEGF and AQP1 were significantly increased, resulting in the inflammation-induced angiogenesis in ARP mice. However, the expression of p-JNK and p-p38 were decreased, leading to the reduction of apoptosis in ARP mice. Excitedly, emodin reversed these changes, not only inhibited inflammation-induced angiogenesis, but also promoted apoptosis. Notably, the effects of emodin were similar to that of AKT inhibitor MK-2206, suggesting the involvement of AKT signaling in the effect of emodin.

CONCLUSION

These results suggest that emodin attenuates ARP in mice, and the underlying mechanism might involve inhibition of the AKT/ERK/NF-κB/VEGF pathways and the induction of apoptosis mediated by JNK and p38.

Metabolite Profiling of Colvillea racemosa via UPLC-ESI-QTOF-MS Analysis in Correlation to the In Vitro Antioxidant and Cytotoxic Potential against A549 Non-Small Cell Lung Cancer Cell Line

In this study, flower and leaf extracts of Colvillea racemosa were considered a source of bioactive compounds. In this context, the objective of the study focused on investigating the anticancer potential as well as the phytochemical composition of both extracts. The extracts were analyzed by UPLC-ESI-QTOF-MS, and the bioactivity was tested using in vitro antioxidant assays (FRAP, DPPH, and ABTS) in addition to cytotoxic assays on non-small cell lung cancer cell line (A549). Our results clearly indicated the potent radical scavenging capacity of both extracts. Importantly, the flower extract exhibited a greater antioxidant capacity than the leaf extract. In terms of cytotoxic activity, leaf and flower extracts significantly inhibited cell viability with IC50 values of 17.0 and 17.2 µg/mL, respectively. The phytochemical characterization enabled the putative annotation of 42 metabolites, such as saccharides, phenolic acids, flavonoids, amino acids, and fatty acids. Among them, the flavonoid C-glycosides stand out due to their high relative abundance and previous reports on their anticancer bioactivity. For a better understanding of the bioactive mechanisms, four flavonoids (vitexin, kaempferol-3-O-rutinoside, luteolin, and isoorientin) were selected for molecular docking on hallmark protein targets in lung cancer as represented by γ-PI3K, EGFR, and CDK2 through in-silico studies. In these models, kaempferol-3-O-rutinoside and vitexin had the highest binding scores on γ-PI3K and CDK2, followed by isoorientin, so they could be highly responsible for the bioactive properties of C. racemosa extracts.

Physicochemical Features and Applicability of Newly Fabricated Phytopharmaceutical-Loaded Hydrogel Alginate Microcarriers with Viscoelastic Polyelectrolyte Coatings

The design of novel polymeric carrier systems with functional coatings is of great interest for delivering various bioactive molecules. Microcapsules coated with polyelectrolyte (PE) films provide additional functionality and fine-tuning advantages essential for controlled drug release. We developed hydrogel microcarriers coated with functional PE films with encapsulated substances of natural origin, resveratrol (RES), curcumin (CUR), and epigallocatechin gallate (EGCG), which have cytotoxic and chemopreventive properties. Alginate (ALG) based microparticles were loaded with phytopharmaceuticals using the emulsification method, and then their surface was modified with PE coatings, such as chitosan (CHIT) or poly(allylamine hydrochloride) (PAH). The morphology and mean diameter of microcarriers were characterised by scanning electron microscopy, encapsulation efficiency was determined by UV-Vis spectroscopy, whereas the physicochemical properties of functional PE layers were studied using quartz crystal microbalance with dissipation monitoring and streaming potential measurements. The release profiles of active compounds from the hydrogel microparticles were described using the Peppas-Sahlin model. The cytotoxic effect of designed delivery systems was studied by evaluating their impact on the proliferation, mitochondrial metabolic function, and lipid peroxidation level of 5637 human bladder cancer cells. The present work demonstrates that the physicochemical and biological features of fabricated microcarriers can be controlled by the type of encapsulated anti-cancer agent and PE coating.

Polyphenol Supplementation Enhances the Efficacy of PD-1/PD-L1 Inhibitors Against Cancer: A Meta-Analysis of Animal Studies

BACKGROUND

This study performed a meta-analysis to evaluate the combined effects of polyphenols and anti-programmed cell death-1 (PD-1)/programmed cell death ligand-1 (PD-L1) inhibitors.

METHODS

Relevant studies were collected from electronic databases. Standardized mean differences (SMDs) or hazard ratio (HR) was calculated by Stata 15.0 software.

RESULTS

Sixteen preclinical studies were included. The overall meta-analysis showed that, compared to anti-PD-1/PD-L1 alone, polyphenol combined therapy significantly reduced the tumor volume (SMD = -3.28), weight (SMD = -2.18), number (SMD = -2.17), and prolonged the survival (HR = 0.45) of mice (all P < 0.001). Pooled analysis of mechanism studies indicated polyphenol combined therapy could increase the number of cytotoxic CD8+ T cells (SMD = 3.88; P < 0.001), IFN-γ+ CD8+ T cells (SMD = 2.38; P < 0.001), decrease the number of myeloid-derived suppressor cells (SMD = -2.52; P = 0.044) and Treg cells (SMD = -4.00; P = 0.004) and suppress PD-L1 expression in tumors (SMD = -13.41; P < 0.001). Subgroup analyses demonstrated curcuminoids, flavonoids, and stilbene changed the tumor volume, the percentage of CD8+ T cells, IFN-γ+CD8+ T cells, and PD-L1 expression.

CONCLUSION

Polyphenol supplementation may be a promising combined strategy for patients with poor response to anti-PD-1/PD-L1 monotherapy.

Synergistic anti-proliferative and apoptotic effect of NVP-BEZ235 and curcumin on human SH-SY5Y neuroblastoma cells

Neuroblastoma, a tumor of the sympathetic nervous system, is one of the most common tumors found in children. Most patients develop resistance to therapy and show poor prognosis, thus there is a need of novel therapeutic agents for the treatment of neuroblastoma. NVP-BEZ235 is a dual Phosphatidylinositol 3-kinase (PI3K)/mammalian target of rapamycin (mTOR) kinase inhibitor that induces apoptosis and suppresses the growth of cancer. Curcumin acts as an anticancer agent in certain cancers. This study investigated the synergetic effect of NVP-BEZ235 and curcumin against neuroblastoma SH-SY5Y cell line. In the current study, the synergic effect of NVP-BEZ235 and curcumin in SH-SY5Y was examined in terms of the cell growth by cell viability and colony forming assay, cell cycle and apoptotic cell death by flow cytometry and mRNA expression levels by quantitative Real Time Polymerase Chain Reaction (qRT-PCR). Curcumin, NVP-BEZ235 or a combination of both, showed cytotoxicity in a dose and time dependent manner in SH-SY5Y cells. 10 µM curcumin and 200 nM NVP-BEZ235 were chosen as combination therapy, as the combination index showed synergism. Colony forming assay showed decrease in cell growth in combination group. The cell cycle distribution for combination group demonstrated a decrease in G0/G1 phase at 48 h. Annexin V showed an anticancer effect in combination group when compared to control group. Moreover, qRT-PCR results showed a significant increase in caspase 3, caspase 7, Bax and p53 genes, while a decrease in Bcl-2 gene expression levels. These findings suggest that combination therapy of NVP-BEZ235 and curcumin may be a promising therapeutic candidate for treatment of neuroblastoma.

Investigation of the combined cytotoxicity induced by sodium butyrate and a flavonoid quercetin treatment on MCF-7 breast cancer cells

Quercetin (QUE) belonging to the flavonoid class is a common phytochemical present in the daily diet of some individuals. Quercetin is an important source of free radical scavengers. This property makes this flavonoid a reliable antioxidant with the following properties: anti-inflammatory, anti-diabetic, antimicrobial and anti-carcinogenic. Sodium butyrate (NaBu) acts as a histone deacetylase inhibitor (HDACi) and is known to regulate apoptosis in cancer cells. Combining natural flavonoids such as QUE with different substances may synergistically enhance their anti-carcinogenic capacity. Thus, the aim of this study was to examine the combined treatment effects of QUE and NaBu in hormone-sensitive breast cancer cells in vitro. MCF-7 breast cancer cells were treated with QUE alone, NaBu alone, as well as QUE and NaBu combined to determine the following: cell proliferation, levels of protein annexin A5 (ANXA5) and reactive oxygen species (ROS), mRNA protein expression, as well as cell and nuclear morphology. Data demonstrated that either QUE or NaBu alone inhibited cell proliferation, and reduced levels protein ANXA5, ROS and mRNA protein expression, The combination of QUE and NaBu produced a significant synergistic inhibitory effect compared to treatment groups of QUE or NaBu alone. In conclusion, our findings showed that the combination treatment of QUE and NaBu may constitute a promising therapeutic approach to breast cancer treatment but this needs further molecular and in vivo investigations.

Polyphenol-Based Nanosystems for Next-Generation Cancer Therapy: Multifunctionality, Design, and Challenges

With the continuous updating of cancer treatment methods and the rapid development of precision medicine in recent years, there are higher demands for advanced and versatile drug delivery systems. Scientists are committed to create greener and more effective nanomedicines where the carrier is no longer limited to a single function of drug delivery. Polyphenols, which can act as both active ingredients and fundamental building blocks, are being explored as potential multifunctional carriers that are efficient and safe for design purposes. Due to their intrinsic anticancer activity, phenolic compounds have shown surprising expressiveness in ablation of tumor cells, overcoming cancer multidrug resistance (MDR), and enhancing immunotherapeutic efficacy. This review provides an overview of recent advances in the design, synthesis, and application of versatile polyphenol-based nanosystems for cancer therapy in various modes. Moreover, the merits of polyphenols and the challenges for their clinical translation are also discussed, and it is pointed out that the novel polyphenol delivery system requires further optimization and validation.

Versatile function of AMPK signaling in osteosarcoma: An old player with new emerging carcinogenic functions

AMP-activated protein kinase (AMPK) signaling has a versatile role in Osteosarcoma (OS), an aggressive bone malignancy with a poor prognosis, particularly in cases that have metastasized or recurred. This review explores the regulatory mechanisms, functional roles, and therapeutic applications of AMPK signaling in OS. It focuses on the molecular activation of AMPK and its interactions with cellular processes like proliferation, apoptosis, and metabolism. The uncertain role of AMPK in cancer is also discussed, highlighting its potential as both a tumor suppressor and a contributor to carcinogenesis. The therapeutic potential of targeting AMPK signaling in OS treatment is examined, including direct and indirect activators like metformin, A-769662, resveratrol, and salicylate. Further research is needed to determine dosing, toxicities, and molecular mechanisms responsible for the anti-osteosarcoma effects of these compounds. This review underscores the complex involvement of AMPK signaling in OS and emphasizes the need for a comprehensive understanding of its molecular mechanisms. By elucidating the role of AMPK in OS, the aim is to pave the way for innovative therapeutic approaches that target this pathway, ultimately improving the prognosis and quality of life for OS patients.

Circ_0005276 Promotes Prostate Cancer Progression Through the Crosstalk of miR-128-3p/DEPDC1B Axis

This study aimed to investigate more detailed functions of circ_0005276 in prostate cancer (PCa) and provide a novel mechanism for circ_0005276 action. The expression of circ_0005276, microRNA-128-3p (miR-128-3p) and DEP domain containing 1B (DEPDC1B) was detected by quantitative real-time PCR. In functional assays, cell proliferation was determined by CCK-8 assay and EdU assay. Cell migration and invasion were determined by transwell assay. The ability of angiogenesis was determined by tube formation assay. Cell apoptosis was determined by flow cytometry assay. The potential binding relationship between miR-128-3p and circ_0005276 or DEPDC1B was ascertained by dual-luciferase reporter assay and RIP assay. Mouse models were used to verify the role of circ_0005276 in vivo. The upregulation of circ_0005276 was determined in PCa tissues and cells. Circ_0005276 knockdown inhibited proliferation, migration, invasion and angiogenesis in PCa cells, and circ_0005276 knockdown also blocks tumor growth in vivo. Mechanism analysis discovered that miR-128-3p was a target of circ_0005276, and miR-128-3p inhibition recovered circ_0005276 knockdown-inhibited proliferation, migration, invasion and angiogenesis. In addition, DEPDC1B was a target of miR-128-3p, and miR-128-3p restoration-inhibited proliferation, migration, invasion and angiogenesis were rescued by DEPDC1B overexpression. Circ_0005276 might promote the development of PCa by activating the expression of DEPDC1B via targeting miR-128-3p.

Relief of gouty arthritis in rats by total saponins from Dioscorea nipponica Makino through suppression of neutrophil extracellular trap formation via the PI3K/AKT/mTOR axis

Gouty arthritis (GA) is an inflammatory disorder that is associated with elevated serum levels of uric acid. Total saponins from Dioscorea nipponica Makino (TSDN) are a natural component that ameliorates inflammation while also decreasing uric acid levels. The aim of the present study was to unravel the mechanism of TSDN in gouty rats in regard to regulation of the formation of neutrophil extracellular traps (NETs) via the PI3K/AKT/mTOR axis. A total of 40 Wistar rats were divided into 4 groups: normal, model, TSDN and rapamycin groups. Reverse-transcription-quantitative PCR (RT-qPCR) and western blot analysis were used to assess the mRNA and protein expression levels of the PI3K/AKT/mTOR axis. The formation of NETs was detected by immunohistochemical and immunofluorescent methods. ELISA was used to measure the levels of IL-1β and TNF-α. RT-qPCR and western blotting demonstrated that TSDN compromised the mRNA and protein expression levels of activated protein kinase (AMPK) and mTOR, as well as the mRNA expression levels of AKT and PTEN. Furthermore, it increased the protein expression levels of phosphorylated (p-) PI3K, p-AKT and p-AMPK. Immunohistochemical and immunofluorescent analyses revealed that TSDN decreased the protein expression levels of neutrophil elastase, proteinase 3, cathepsin G, lactoferrin and myeloperoxidase, as well as the number of citrullinated histone 3+ cells. TSDN also reduced the release of IL-1β and TNF-α. Overall, the anti-inflammatory action of TSDN in gouty rats may be realized by suppressing the formation of NETs by regulating the PI3K/AKT/mTOR axis.

Design and synthesis of novel hexahydrobenzo[4,5]thieno[2,3-d]pyrimidine derivatives as potential anticancer agents with antiangiogenic activity via VEGFR-2 inhibition, and down-regulation of PI3K/AKT/mTOR signaling pathway

New thieno[2,3-d]pyrimidine derivatives were designed and synthesized. The National Cancer Institute (NCI) evaluated the synthesized novel compounds against a panel of 60 tumor cell lines for their antiproliferative activity. Compounds 6b, 6f, and 6g showed potent anticancer activity at 10 µM dose, with mean GI of 20.86%, 76.41%, and 31.49%, respectively. Compound 6f was selected for five-dose concentrations evaluation. Compound 6f scored a submicromolar range of GI50 values against 10 cancer cell lines, indicating broad-spectrum and potent antiproliferative activity. Compound 6f TGI values were recorded in the cytostatic range of 4.02-95.1 µM. In comparison to sorafenib, the tested compounds 6b, 6f, and 6g inhibited VEGFR-2 with IC50 values of 0.290 ± 0.032, 0.066 ± 0.004, and 0.16 ± 0.006 µM, correspondingly. Compound 6f significantly reduced the total VEGFR-2 expression and its phosphorylation. Additionally, 6f reduced the phosphorylation of PI3K, Akt, and mTOR pathway proteins. Moreover, the migratory potential of HUVECs was significantly reduced, after 72 h of treatment with compound 6f, resulting in disrupted wound healing patterns which verified the angiogenesis suppression properties of compound 6f. Compound 6f increased the total apoptosis percentage by 21.27-fold compared to sorafenib, which caused a 24.11-fold increase in the total apoptosis percentage. This apoptotic activity was accompanied by a 7.81-fold increase in the level of apoptotic caspase-3. Furthermore, the cell cycle analysis revealed that the target derivative 6f reduced cellular proliferation and induced an arrest in HCT-15 colon cancer cell cycle at the S phase. Molecular modeling was used to determine the binding profile and affinity of derivative 6f toward the VEGFR-2 active site.

Enhanced Expression of p53 and Suppression of PI3K/Akt/mTOR by Three Red Sea Algal Extracts: Insights on Their Composition by LC-MS-Based Metabolic Profiling and Molecular Networking

Brown algae comprise up to 2000 species with wide dissemination in temperate zones. A comprehensive untargeted metabolic profiling guided by molecular networking of three uninvestigated Red-Sea-derived brown algae, namely Sirophysalis trinodis, Polycladia myrica, and Turbinaria triquetra, led to the identification of over 115 metabolites categorized as glycerolipids, fatty acids, sterol lipids, sphingolipids, and phospholipids. The three algae exhibited low-to-moderate antioxidant capacity using DPPH and ABTS assays. Preliminary in vitro antiproliferative studies showed that the algal extracts displayed high cytotoxic activity against a panel of cancer cell lines. The most potent activity was recorded against MCF-7 with IC₅₀ values of 51.37 ± 1.19, 63.44 ± 1.13, and 59.70 ± 1.22 µg/mL for S. trinodis, P. myrica, and T. triquetra, respectively. The cytotoxicity of the algae was selective to MCF-7 without showing notable effects on the proliferation of normal human WISH cells. Morphological studies revealed that the algae caused cell shrinkage, increased cellular debris, triggered detachment, cell rounding, and cytoplasmic condensation in MCF-7 cancer cells. Mechanistic investigations using flow cytometry, qPCR, and Western blot showed that the algae induced apoptosis, initiated cell cycle arrest in the sub-G₀/G₁ phase, and inhibited the proliferation of cancer cells via increasing mRNA and protein expression of p53, while reducing the expression of PI3K, Akt, and mTOR.

Natural products modulate cell apoptosis: a promising way for treating endometrial cancer

Endometrial cancer (EC) is a prevalent epithelial malignancy in the uterine corpus's endometrium and myometrium. Regulating apoptosis of endometrial cancer cells has been a promising approach for treating EC. Recent in-vitro and in-vivo studies show that numerous extracts and monomers from natural products have pro-apoptotic properties in EC. Therefore, we have reviewed the current studies regarding natural products in modulating the apoptosis of EC cells and summarized their potential mechanisms. The potential signaling pathways include the mitochondria-dependent apoptotic pathway, endoplasmic reticulum stress (ERS) mediated apoptotic pathway, the mitogen-activated protein kinase (MAPK) mediated apoptotic pathway, NF-κB-mediated apoptotic pathway, PI3K/AKT/mTOR mediated apoptotic pathway, the p21-mediated apoptotic pathway, and other reported pathways. This review focuses on the importance of natural products in treating EC and provides a foundation for developing natural products-based anti-EC agents.

Inula viscosa (L.) Aiton Ethanolic Extract Inhibits the Growth of Human AGS and A549 Cancer Cell Lines

The present study shows the chemical profile and cytotoxic properties of the ethanolic extracts of Inula viscosa from Northeast Algeria. The extract was obtained by maceration using ethanol. Its phenolic profile was determined using ultra-high-performance liquid chromatography coupled with a diode array detector and an electrospray mass spectrometer (UHPLC-DAD-ESI/MS), which allowed the identification and quantification of 17 compounds, 1,5-O-caffeoylquinic acid being the most abundant. The cytotoxic activity was assessed against human gastric cancer (AGS) and human non-small-cell lung cancer (A549) cell lines, whereas ethanolic extract elicited nearly 60 % and 40 % viability loss toward AGS and A549 cancer cells, respectively. Results also showed that cell death is caspase-independent and confirmed the involvement of RIPK1 and the necroptosis pathway in the toxicity induced by the I. viscosa extract. In addition, the ethanolic extract would not provoke morphological traits in the cancer cells. These findings suggest that I. viscosa can be a source of new antiproliferative drugs or used in preparation plant-derived pharmaceuticals.

Cell-free Lactiplantibacillus plantarum OC01 supernatant suppresses IL-6-induced proliferation and invasion of human colorectal cancer cells: Effect on β-Catenin degradation and induction of autophagy

Background and aim

Gut microbiota is considered as a complex organ of human body. The interaction between the host and microbiota is dynamic and controlled by a huge number of factors, such as lifestyle, geography, pharmaceuticals, diet, and stress. The breakdown of this relationship could change microbiota composition favoring the onset of several diseases, including cancer. Metabolites released by microbiota bacterial strains have been reported to elicit protective effects on the mucosa that could contrast cancer development and progression. Here, we tested the ability of specific probiotic strain Lactiplantibacillus plantarum OC01-derived metabolites (NCIMB 30624) to contrast the malignant features of colorectal cancer (CRC) cells.

Experimental procedure

The study was performed on two cell lines, HCT116 and HT29, cultured in 2D and 3D, and focused on the hallmarks of cell proliferation and migration.

Results and conclusion

Probiotic metabolites reduced cell proliferation both in 2D and 3D-spheroid cultures, the latter model mimicking the growth in vivo. The bacterial metabolites also contrasted the pro-growth and pro-migratory activity of inteurleukin-6 (IL-6), an inflammatory cytokine abundantly found in the tumor microenvironment of CRC. These effects were associated with inhibition of the ERK and of the mTOR/p70S6k pathways and with the inhibition of the E-to N-Cadherin switch. In a parallel study, we found that sodium butyrate (a representative of the main probiotic metabolites) induced autophagy and β-Catenin degradation, which is consistent with the growth inhibitory activity. The present data indicate that the metabolites of Lactiplantibacillus plantarum OC01 (NCIMB 30624) elicits anti-tumor effect and support its possible inclusion as adjuvant therapy of CRC for limiting cancer growth and progression.

Metabolomics Analysis Reveals Novel Targets of Chemosensitizing Polyphenols and Omega-3 Polyunsaturated Fatty Acids in Triple Negative Breast Cancer Cells

Triple negative breast cancer (TNBC) is a subtype of breast cancer with typically poorer outcomes due to its aggressive clinical behavior and lack of targeted treatment options. Currently, treatment is limited to the administration of high-dose chemotherapeutics, which results in significant toxicities and drug resistance. As such, there is a need to de-escalate chemotherapeutic doses in TNBC while also retaining/improving treatment efficacy. Dietary polyphenols and omega-3 polyunsaturated fatty acids (PUFAs) have been demonstrated to have unique properties in experimental models of TNBC, improving the efficacy of doxorubicin and reversing multi-drug resistance. However, the pleiotropic nature of these compounds has caused their mechanisms to remain elusive, preventing the development of more potent mimetics to take advantage of their properties. Using untargeted metabolomics, we identify a diverse set of metabolites/metabolic pathways that are targeted by these compounds following treatment in MDA-MB-231 cells. Furthermore, we demonstrate that these chemosensitizers do not all target the same metabolic processes, but rather organize into distinct clusters based on similarities among metabolic targets. Common themes in metabolic targets included amino acid metabolism (particularly one-carbon and glutamine metabolism) and alterations in fatty acid oxidation. Moreover, doxorubicin treatment alone generally targeted different metabolites/pathways than chemosensitizers. This information provides novel insights into chemosensitization mechanisms in TNBC.

Targeting mTOR Signaling by Dietary Polysaccharides in Cancer Prevention: Advances and Challenges

Cancer is the most serious problem for public health. Traditional treatments often come with unavoidable side effects. Therefore, the therapeutic effects of natural products with wide sources and low toxicity are attracting more and more attention. Polysaccharides have been shown to have cancer-fighting potential, but the molecular mechanisms remain unclear. The mammalian target of rapamycin (mTOR) pathway has become an attractive target of antitumor therapy research in recent years. The regulation of mTOR pathway not only affects cell proliferation and growth but also has an important effect in tumor metabolism. Recent studies indicate that dietary polysaccharides play a vital role in cancer prevention and treatment by regulating mTOR pathway. Here, the progress in targeting mTOR signaling by dietary polysaccharides in cancer prevention and their molecular mechanisms are systemically summarized. It will promote the understanding of the anticancer effects of polysaccharides and provide reference to investigators of this cutting edge field.

Downregulation of MDM2 by small interference RNA induces apoptosis and sensitizes MCF-7 breast cells to resveratrol

Recent studies have demonstrated the mouse double minute gene (MDM2), a main oncogene, as a novel and interesting therapeutic target for cancer therapy. The aim of this study was to investigate the involvement of MDM2 in antiproliferative and antimetastatic effects of resveratrol in breast cancer cells. MCF-7 cells were transfected with siRNA against MDM2 and resveratrol. Proliferation and apoptosis were evaluated by MTT assay and cell death ELISA assay, respectively. MDM2, p53, Bax, Bcl-2, caspase-3, MMP-2, and MMP9 expressions were determined by qRT-PCR and Western blotting. Transfection with si-MDM2 significantly suppressed the expression of MDM2 expression, resulting in MCF-7 cell growth inhibition and spontaneous apoptosis. Pretreatment with Si-MDM2 synergically increased antiproliferation and antimetatstatic effects of resveratrol. No significant anticancer effects were detected with negative control siRNA treatment. Our findings suggest that silencing of MDM2 by specific siRNA effectively induce apoptosis and also enhanced anticancer effects of resveratrol. Therefore, siMDM2 may be a potent combination in breast therapy.

Molecular mechanisms underlying ameliorative impact of melatonin against age-dependent chronic arsenic toxicity in rats' brains

Accumulation of random molecular damage such as oxidative DNA damage and inflammation is extremely found to be involved in the aging process. Due to extreme energy requirements and high lipid levels, the brain is more susceptible to oxidative damage during aging especially under exposure to toxic elements such as arsenic. Therefore, this study was aimed to evaluate the ameliorative effects of melatonin, as a neurohormone, on the arsenic-induced behavioral abnormalities, and the underlying mechanisms. Forty-eight rats, as young and old aged groups were exposed to 5.55 g/kg body weight arsenic for 4 weeks and then 10 mg/kg melatonin for 2 weeks. Our results showed that arsenic led to anxiety-like behavioral abnormalities in rats. Increased oxidative stress-induced damage to DNA, lipids and proteins, decreased potential of antioxidant defense system, induced apoptosis, elevated inflammation, and alteration in the histology of cortical region of brains are observed in the rats exposed to arsenic. These effects were more prominent in aged rats in comparison to young rats. Melatonin successfully attenuates arsenic induced adverse effects on the brain in both age groups. In conclusion, our study shows that melatonin has significant ameliorative impact on age-dependent cytotoxicity of arsenic in rats' brains.

3-Deoxysappanchalcone isolated from Caesalpinia sinensis shows anticancer effects on HeLa and PC3 cell lines: invasion, migration, cell cycle arrest, and signaling pathway

To study the antitumor activity of compound 3-desoxysulforaphane (3-DSC) isolated from Caesalpinia sinensis, SRB assay, clone formation assay, flow cytometric cell cycle assay, scratch assay, transwell assay, and molecular docking were used to investigate the inhibitory effect of 3-DSC on HeLa and PC3 cells. The results showed that 3-DSC inhibited the cell migration and invasion by down-regulating expression of N-cadherin, Vimentin, MMP-2, and MMP-9 in HeLa and PC3 cells; It also inhibits cell proliferation by promoting the expression of CDK1 (cyclin-dependent kinases 1) and CDK2 (cyclin-dependent kinases 2), which arrests the tumor cell cycle at G2 phase. 3-DSC inhibits phosphorylation of AKT and ERK and upregulates the expression of the tumor suppressor gene p53. Molecular docking results confirmed that 3-DSC could bind firmly to AKT. In conclusion, 3-DSC inhibited the proliferation, migration and invasion of HeLa and PC3 cells.

1-(4-((5-chloro-4-((2-(isopropylsulfonyl)phenyl)amino)pyrimidin-2-yl)amino)-3-methoxyphenyl)-3-(2-(dimethylamino)ethyl)imidazolidin-2-one (ZX-42) inhibits cell proliferation and induces apoptosis via inhibiting ALK and its downstream pathways in Karpas299 cells

Anaplastic lymphoma kinase (ALK) belongs to the family of receptor tyrosine kinases. Recently, the incidence of anaplastic large cell lymphoma (ALCL) with ALK rearrangement has raised considerably. The application of ALK-targeted inhibitors such as ceritinib provides an effective therapy for the treatment of ALK-positive cancers. However, with the prolongation of treatment time, the emergence of resistance is inevitable. We found that 1-(4-((5-chloro-4-((2-(isopropylsulfonyl)phenyl)amino)pyrimidin-2-yl)amino)-3-methoxyphenyl)-3-(2-(dimethylamino)ethyl)imidazolidin-2-one (ZX-42), a novel ceritinib derivative, could inhibit the proliferation of ALK-positive ALCL cells, induce the apoptosis of Karpas299 cells through the mitochondrial pathway in a caspase-dependent manner. In addition, ZX-42 could suppress ALK and downstream pathways including PI3K/Akt, Erk and JAK3/STAT3 and reduce the nuclear translocation of NFκB by inhibiting TRAF2/IKK/IκB pathway. Taken together, our findings indicate that ZX-42 shows more effective activity than ceritinib against ALK-positive ALCL. We hope this study can provide a direction for the structural modification of ceritinib and lay the foundation for the further development of clinical research in ALK-positive ALCL.

SLC6A14 Depletion Contributes to Amino Acid Starvation to Suppress EMT-Induced Metastasis in Gastric Cancer by Perturbing the PI3K/AKT/mTORC1 Pathway

Metastasis is the main obstacle for the treatment of gastric cancer (GC), leading to low survival rate and adverse outcomes in CG patients. SLC6A14, a general amino acid transporter, can import all the essential amino acids in a manner dependent on the NaCl-generated osmotic gradients. Herein, we constructed GC cell sublines with high (SGC7901-M and MKN28-M) and low (MKN28-NM and SGC7901-NM) metastatic ability. Putative functional genes advancing GC metastasis were identified using mRNA microarray analysis and High-Content Screening. In particular, most significant change with a dampening trend in the migration potentiality of GC cells emerged after SLC6A14 gene was silenced. SLC6A14 expression was positively correlated with the migrated capability of different GC cell lines, and SLC6A14 was also constitutively expressed in GC patients with venous or lymphatic invasion, lymph node, or distant metastasis and poor prognosis, thus prompting SLC6A14 as a nonnegligible presence in supporting GC migration and invasion. Consistently, SLC6A14 depletion drastically depressed GC metastasis in vitro and in vivo. Most importantly, pharmacological blockade and gene silence of SLC6A14 both restricted epithelial-mesenchymal transition- (EMT-) driven GC metastasis, in which attenuated activation of the PI3K/AKT/mTORC1 pathway caused by amino acid starvation was involved. In summary, it is conceivable that targeting SLC6A14 has a tremendous promising for the treatment of metastatic GC.

Studies Regarding the Pharmaceutical Potential of Derivative Products from Plantain

In this study, three types of extracts isolated from leaves of Plantain (Plantago lanceolata) were tested for their chemical content and biological activities. The three bioproducts are combinations of polysaccharides and polyphenols (flavonoids and iridoidic compounds), and they were tested for antioxidant, antifungal, antitumor, and prebiotic activity (particularly for polysaccharides fraction). Briefly, the iridoid-enriched fraction has revealed a pro-oxidant activity, while the flavonoid-enriched fraction had a high antioxidant potency; the polysaccharide fraction also indicated a pro-oxidant activity, explained by the co-presence of iridoid glycosides. All three bioproducts demonstrated moderate antifungal effects against Aspergillus sp., Penicillium sp., and dermatophytes, too. Studies in vitro proved inhibitory activity of the three fractions on the leukemic tumor cell line THP-1, the main mechanism being apoptosis stimulation, while the polysaccharide fraction indicated a clear prebiotic activity, in the concentration range between 1 and 1000 µg/mL, evaluated as higher than that of the reference products used, inulin and dextrose, respectively.

The Therapeutic Potential of Kaemferol and Other Naturally Occurring Polyphenols Might Be Modulated by Nrf2-ARE Signaling Pathway: Current Status and Future Direction

Kaempferol is a natural flavonoid, which has been widely investigated in the treatment of cancer, cardiovascular diseases, metabolic complications, and neurological disorders. Nrf2 (nuclear factor erythroid 2-related factor 2) is a transcription factor involved in mediating carcinogenesis and other ailments, playing an important role in regulating oxidative stress. The activation of Nrf2 results in the expression of proteins and cytoprotective enzymes, which provide cellular protection against reactive oxygen species. Phytochemicals, either alone or in combination, have been used to modulate Nrf2 in cancer and other ailments. Among them, kaempferol has been recently explored for its anti-cancer and other anti-disease therapeutic efficacy, targeting Nrf2 modulation. In combating cancer, diabetic complications, metabolic disorders, and neurological disorders, kaempferol has been shown to regulate Nrf2 and reduce redox homeostasis. In this context, this review article highlights the current status of the therapeutic potential of kaempferol by targeting Nrf2 modulation in cancer, diabetic complications, neurological disorders, and cardiovascular disorders. In addition, we provide future perspectives on kaempferol targeting Nrf2 modulation as a potential therapeutic approach.

Thymoquinone Potentiates Methotrexate Mediated-Apoptosis in Saos-2 Osteosarcoma Cell Line

INTRODUCTION

Recently, various studies have concentrated on the therapeutic potential of thymoquinone (TQ), a natural polyphenol, in various human malignancies, including osteosarcoma. However, the underlying mechanisms in TQ-mediated anti-cancer effects are not yet fully understood. Therefore, the present study investigated the effect of TQ on methotrexate (MTX)-induced apoptosis in Saos-2 cells.

METHODS

Saos-2 cells were treated with MTX, TQ, and a combination of both, and cell viability was assessed by MTT assay. mRNA expression of apoptotic markers, including Bax, Bcl-2, and caspase-3, was assessed using quantitative real-time polymerase chain reaction (qRT-PCR).

RESULTS

MTX resulted in significant inhibition of cell proliferation in a dose-dependent manner. The combination of TQ and MTX inhibited proliferation compared to single treatments (P<0.05). TQ also induced apoptosis by regulating pro-apoptotic markers including Bax and caspase-3 and reducing anti-apoptotic mediators including Bcl-2. In addition, TQ increased MTX-induced apoptosis in Saos-2 cells.

CONCLUSION

The findings of the present study highlight new insights into understanding the role of TQ as a potential therapeutic agent in osteosarcoma by increasing MTX-induced apoptosis.

Health benefits of polyphenols: A concise review

Plants produce polyphenols, which are considered highly essential functional foods in our diet. They are classified into several groups according to their diverse chemical structures. Flavanoids, lignans, stilbenes, and phenolic acids are the four main families of polyphenols. Several in vivo and in vitro research have been conducted so far to evaluate their health consequences. Polyphenols serve a vital function in the protection of the organism from external stimuli and in eliminating reactive oxygen species (ROS), which are instigators of several illnesses. Polyphenols are present in tea, chocolate, fruits, and vegetables with the potential to positively influence human health. For instance, cocoa flavan-3-ols have been associated with a decreased risk of myocardial infarction, stroke, and diabetes. Polyphenols in the diet also help to improve lipid profiles, blood pressure, insulin resistance, and systemic inflammation. Quercetin, a flavonoid, and resveratrol, a stilbene, have been linked to improved cardiovascular health. Dietary polyphenols potential to elicit therapeutic effects might be attributed, at least in part, to a bidirectional association with the gut microbiome. This is because polyphenols are known to affect the gut microbiome composition in ways that lead to better human health. Specifically, the gut microbiome converts polyphenols into bioactive compounds that have therapeutic effects. In this review, the antioxidant, cytotoxicity, anti-inflammatory, antihypertensive, and anti-diabetic actions of polyphenols are described based on findings from in vivo and in vitro experimental trials. PRACTICAL APPLICATIONS: The non-communicable diseases (NCDs) burden has been increasing worldwide due to the sedentary lifestyle and several other factors such as smoking, junk food, etc. Scientific literature evidence supports the use of plant-based food polyphenols as therapeutic agents that could help to alleviate NCD's burden. Thus, consuming polyphenolic compounds from natural sources could be an effective solution to mitigate NCDs concerns. It is also discussed how natural antioxidants from medicinal plants might help prevent or repair damage caused by free radicals, such as oxidative stress.

Tanshinone IIA protects against chronic obstructive pulmonary disease via exosome‑shuttled miR‑486‑5p

Chronic obstructive pulmonary disease (COPD) is one of the major causes of death worldwide today, and its related morbidity has been predicted to show an increase in subsequent years. Recent studies have shown that Danshen, a Chinese herbal medicine, is a potential drug in the treatment of inflammation-related lung diseases. COPD was induced in this study using cigarette smoke (CS) exposure plus intranasal inhalation of lipopolysaccharide to ascertain whether the main pharmacological component from Danshen, tanshinone IIA (TIIA), and its water soluble form, sodium tanshinone IIA sulfonate (STS), protect against the development of COPD. The weight, lung function, hematoxylin and eosin staining, and Masson Trichrome determinations revealed that TIIA inhalation attenuated lung dysfunction in COPD mice induced by cigarette smoke and lipopolysaccharide exposure. In addition, exosomes derived from TIIA-treated COPD mice exerted similar protective effects against COPD, suggesting that TIIA may protect against COPD through exosome-shuttled signals. miR-486-5p was found to be a key molecule in mediating the protective effects of exosomes derived from TIIA-treated COPD mice using miRNA sequencing and cellular screening. Treatment of COPD mice with an agomiR of miR-486-5p protected lung function in COPD mice, and treatment of COPD mice with an antagomir of miR-486-5p abolished the protective effects of TIIA. Moreover, luciferase activity reporter assay, RT-qPCR, and western blot analyses showed that miR-486-5p exerted protective effects against COPD via targeting phosphoinositide-3-kinase regulatory subunit 1 (PIK3R1). These results suggest that STS protects against COPD through upregulation of miR-486-5p, and that TIIA or miR-486-5p is a potential drug for the treatment of COPD.

A Review of Twenty Years of Research on the Regulation of Signaling Pathways by Natural Products in Breast Cancer

Breast cancer (BC) is the second leading cause of death among women, and it has become a global health issue due to the increasing number of cases. Different treatment options, including radiotherapy, surgery, chemotherapy and anti-estrogen therapy, aromatase inhibitors, anti-angiogenesis drugs, and anthracyclines, are available for BC treatment. However, due to its high occurrence and disease progression, effective therapeutic options for metastatic BC are still lacking. Considering this scenario, there is an urgent need for an effective therapeutic strategy to meet the current challenges of BC. Natural products have been screened as anticancer agents as they are cost-effective, possess low toxicity and fewer side effects, and are considered alternative therapeutic options for BC therapy. Natural products showed anticancer activities against BC through the inhibition of angiogenesis, cell migrations, proliferations, and tumor growth; cell cycle arrest by inducing apoptosis and cell death, the downstream regulation of signaling pathways (such as Notch, NF-κB, PI3K/Akt/mTOR, MAPK/ERK, and NFAT-MDM2), and the regulation of EMT processes. Natural products also acted synergistically to overcome the drug resistance issue, thus improving their efficacy as an emerging therapeutic option for BC therapy. This review focused on the emerging roles of novel natural products and derived bioactive compounds as therapeutic agents against BC. The present review also discussed the mechanism of action through signaling pathways and the synergistic approach of natural compounds to improve their efficacy. We discussed the recent in vivo and in vitro studies for exploring the overexpression of oncogenes in the case of BC and the current status of newly discovered natural products in clinical investigations.

Silibinin exerts anti-cancer activity on human ovarian cancer cells by increasing apoptosis and inhibiting epithelial-mesenchymal transition (EMT)

BACKGROUND

Silibinin, the principal flavonoid derived from milk thistle seeds, has been demonstrated to have strong inhibitory effects against human malignancies. The inhibitory function of silibinin on ovarian cancer, however, is not fully identified. In this essay, both in vivo and in vitro investigations were conducted to survey the silibinin's blocking effects on ovarian cancer.

METHODS

The impacts of silibinin on two ovarian cancer cell lines, SKOV-3 and A2870, were determined by evaluating cell viability, migration, invasion, and apoptosis. Q-RT-PCR and western blotting techniques were carried out to explore the protein levels of signaling pathway markers. A mouse xenograft model was utilized to determine the silibinin efficacy in inhibiting tumor growth.

RESULTS

After cell treatment with silibinin, cell viability, migration, and invasion were appreciably inhibited in cancer cell lines, but cell apoptosis was promoted. Also, silibinin reversed the epithelial-mesenchymal transition (EMT) mechanism by inducing E-cadherin expression and reducing N-cadherin and vimentin expression, suppressing the levels of regulators related to EMT such as Snail, Slug, and ZEB1 transcription factors, and also decreasing PI3K/AKT, Smad2/3, and β-catenin intermediate molecules in vitro. Silibinin effectively ameliorated tumor growth in vivo.

CONCLUSION

silibinin could be considered a potent agent against ovarian cancer based on the results.

Associations of Genetic Polymorphisms of mTOR rs2295080 T/G and rs1883965 G/A with Susceptibility of Urinary System Cancers

Background. Genetic polymorphisms in mammalian target of rapamycin (mTOR) signaling axis can influence the susceptibility of cancer. The relationship between mTOR gene variants rs2295080 T/G and rs1883965 G/A and the risk of cancer remains inconsistent. The present study is aimed at comprehensively investigating the association between mTOR polymorphisms and susceptibility to cancer. Methods. We conducted a comprehensive assessment using odds ratios (ORs), corresponding 95% confidence intervals (CIs), and in silico tools to evaluate the effect of mTOR variations. Immunohistochemical staining (IHS) and GSEA analysis were used to investigate the expression of mTOR in urinary system cancer. Results. The pooled analysis involved 22 case-control studies including 14,747 cancer patients and 16,399 controls. The rs2295080 T/G polymorphism was associated with the risk of cancer (G-allele versus T-allele, $\text{OR}=0.89$ , $95\%\text{CI}=0.80$ –0.98, $P=0.023$ ; GT versus TT, $\text{OR}=0.88$ , $95\%\text{CI}=0.81$ –0.96, $P=0.004$ ; GG+GT versus TT, $\text{OR}=0.87$ , $95\%\text{CI}=0.78$ –0.96, $P=0.008$ ), especially for cancers of the urinary system, breast, and blood. Variation rs1883965 G/A was associated with cancer susceptibility, especially for digestive cancer. IHS analysis showed that mTOR was upregulated in prostate and bladder cancer. GSEA revealed that the insulin signaling pathway, lysine degradation pathway, and mTOR signaling pathway were enriched in the high mTOR expression group. Conclusions. The mTOR rs2295080 T/G polymorphism may be associated with susceptibility of urinary cancer. The expression of mTOR is positively correlated with tumor malignancy in prostate cancer.

Protein tyrosine phosphatase receptor type Z1 inhibits the cisplatin resistance of ovarian cancer by regulating PI3K/AKT/mTOR signal pathway

Most patients with ovarian cancer (OC) get remission after undergoing cytoreductive surgery and platinum-based standard chemotherapy, but more than 50% of patients with advanced OC relapse within the first 5 years after treatment and develop resistance to standard chemotherapy. The production of medicinal properties is the main reason for the poor prognosis and high mortality of OC patients. Cisplatin (DDP) resistance is a major cause for poor prognosis of OC patients. PTPRZ1 can regulate the growth and apoptosis of ovarian cancer cells, while the molecular mechanism remains unknown. This study was designed to investigate the roles of PTPRZ1 in DDP-resistant OC cells and possible mechanism. PTPRZ1 expression in OC tissues and normal tissues was analyzed by GEPIA database and verified by Real-time Quantitative Reverse Transcription PCR (RT-PCR) assay. PTPRZ1 expression in normal ovarian cancer cells and DDP-resistant OC cells was also analyzed. Subsequently, RT-PCR, Western blot, MTT experiment and flow cytometry were used to assess the effects of PTPRZ1-PI3K/AKT/mTOR regulating axis on DDP resistance of OC. PTPRZ1 expression was abnormally low in OC tissues, and notably reduced in DDP-resistant OC cells. MTT experiment and flow cytometer indicated that overexpression of PTPRZ1 enhanced the DDP sensitivity of OC cells and promoted the cell apoptosis. Moreover, the results of our research showed that PTPRZ1 might exert its biological effects through blocking PI3K/AKT/mTOR pathway. PTPRZ1 overexpression inhibitied OC tumor growth and resistance to DDP in vivo. Overall, PTPRZ1 might suppress the DDP resistance of OC and induce the cytotoxicity by blocking PI3K/AKT/mTOR pathway.

Crosstalk between miRNA and PI3K/AKT/mTOR signaling pathway in cancer

Phosphoinositide-3 kinase (PI3K)/AKT/mammalian target of rapamycin (mTOR) signaling pathway is one of the most important proliferative signaling pathways with critical undeniable function in various aspects of cancer initiation/progression, including proliferation, apoptosis, metastasis, angiogenesis, and drug resistance. On the other hand, numerous genetic alterations in the key genes involved in the PI3K/AKT/mTOR signaling pathway have been identified in multiple solid and hematological tumors. In addition, accumulating recent evidences have demonstrated a reciprocal interaction between this signaling pathway and microRNAs, a large group of small non-coding RNAs. Therefore, in this review, it was attempted to discuss about the interaction between key components of PI3K/AKT/mTOR signaling pathway with various miRNAs and their importance in cancer biology.

Function of selected natural antidiabetic compounds with potential against cancer via modulation of the PI3K/AKT/mTOR cascade

Diabetes mellitus (DM) is a metabolic disorder with growing global incidence, as 387 million people were diagnosed in 2014 with an expected projection of 642 million in 2040. Several complications are associated with DM including heart attack, stroke, kidney failure, blindness, and cancer. The latter is the second leading cause of death worldwide accounting for one in every six deaths, with liver, pancreas, and endometrium cancers are the most abundant among patients with diabetes. Phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt)/mammalian target of rapamycin (mTOR) pathway plays a vital role in developing a wide array of pathological disorders, among them diabetes and cancer. Natural secondary metabolites that counteract the deleterious effects of reactive oxygen species (ROS) and modulate PI3K/Akt/mTOR pathway could be a promising approach in cancer therapy. Here, 717 medicinal plants with antidiabetic activities were highlighted along with 357 bioactive compounds responsible for the antidiabetic activity. Also, 43 individual plant compounds with potential antidiabetic activities against cancer via the modulation of PI3K/Akt/mTOR cascade were identified. Taken together, the available data give an insight of the potential of repurposing medicinal plants and/or the individual secondary metabolites with antidiabetic activities for cancer therapy.

Chinese Medicine Leptochloa chinensis Inhibits the Malignant Behaviors of Renal Cell Carcinoma 786-O Cells by Regulating the mTOR Pathway

BACKGROUND

Renal cell carcinoma (RCC) is a common malignant tumor of the urinary system that seriously threatens human life and health. This study aims to explore the role of the traditional Chinese medicine Leptochloa chinensis in the pathogenesis of RCC. Meanwhile, this study also revealed the molecular biological mechanism of its antitumor activity.

METHODS

Human RCC 786-O cells were cultured in the RPMI-1640 medium, which contains different concentrations of Leptochloa chinensis (1,000, 3,000, and 9,000 μg/ml). MTT and flow cytometry assays were used to detect the viability of 786-O cells. Transwell and wound healing assays were used to detect cell metastasis. The protein expression was observed by western blot analysis.

RESULTS

Leptochloa can inhibit cell proliferation and induce apoptosis in RCC 786-O cells. In addition, Leptochloa can weaken the migration and invasion of 786-O cells. More importantly, Leptochloa can block the mTOR pathway by inhibiting the protein expression of p-mTOR. Moreover, the high concentration of Leptochloa chinensis has a better inhibitory effect on 786-O cells.

CONCLUSION

The traditional Chinese medicine Leptochloa chinensis inhibits the viability and metastasis of 786-O cells by blocking the mTOR pathway.

A dual-targeted molecular therapy of PP242 and cetuximab plays an anti-tumor effect through EGFR downstream signaling pathways in colorectal cancer

Background

Epidermal growth factor receptor (EGFR) and its downstream Ras-mitogen-activated protein kinase kinase (MAPKK, MEK)-extracellular regulated protein kinase (ERK) signaling pathway and phosphatidylinositol 3-kinase (PI3K)-protein kinase B (Akt)-mammalian target of rapamycin (mTOR) signaling pathway play important roles in the pathogenesis of colorectal cancer (CRC). The combination therapy of anti-EGFR and anti-mTOR needs to be explored.

Methods

Here we combined the anti-EGFR monoclonal antibody cetuximab (CTX) with the mTOR inhibitor PP242 in CRC cell lines and mouse xenograft models and discussed the changes of EGFR downstream signaling pathways of CRC cell lines.

Results

In HT-29 cells and Caco-2 cells, combined application of CTX and PP242 significantly inhibited the proliferation of CRC cells in vivo and in vitro. In BRAF wild-type Caco-2 cells, combined application of CTX and PP242 inhibited the activation of the EGFR and its downstream signaling pathways.

Conclusions

Our research further demonstrates the effectiveness of the combined application of CTX and PP242 in inhibiting CRC cell lines from the perspective of cell proliferation, cell cycle, apoptosis, and mouse xenografts. We revealed that the combined application of CTX and PP242 can inhibit tumor growth and proliferation by inhibiting the phosphorylation of key molecules in EGFR downstream MEK-ERK and MEK 4/7 (MKK)-c-Jun N-terminal kinase (JNK) signaling pathways in BRAF wild-type CRC cells. In addition, we found that in BRAF mutant CRC cells, the monotherapy of PP242 resulted in negative feedback increased EGFR phosphorylation rates, accompanied by significant up-regulation of downstream MEK and ERK phosphorylation.

Phytochemicals as PI3K/ Akt/ mTOR Inhibitors and Their Role in Breast Cancer Treatment

BACKGROUND

Breast cancer is the predominant form of cancer in women; various cellular pathways are involved in the initiation and progression of breast cancer. Among the various types of breast cancer that differ in their growth factor receptor status, PI3K/Akt signaling is a common pathway where all these converge. Thus, the PI3K signaling is of great interest as a target for breast cancer prevention; however, it is less explored.

OBJECTIVE

The present review is aimed to provide a concise outline of the role of PI3K/Akt/mTOR pathway in breast carcinogenesis and its progression events, including metastasis, drug resistance and stemness. The review emphasizes the role of natural and synthetic inhibitors of PI3K/Akt/m- TOR pathway in breast cancer prevention.

METHODS

The data were obtained from PubMed/Medline databases, Scopus and Google patent literature.

RESULTS

PI3K/Akt/mTOR signaling plays an important role in human breast carcinogenesis; it acts on the initiation and progression events associated with it. Numerous molecules have been isolated and identified as promising drug candidates by targeting the signaling pathway. Results from clinical studies confirm their application in the treatment of human breast cancer alone and in combination with classical chemotherapeutics as well as monoclonal antibodies.

CONCLUSION

PI3K/mTOR signaling blockers have evolved as promising anticancer agents by interfering breast cancer development and progression at various stages. Natural products and bioactive components are emerging as novel inhibitors of PI3K signaling and more research in this area may yield numerous drug candidates.

Anti-Cancer Activity and Phenolic Content of Extracts Derived from Cypriot Carob (Ceratonia siliqua L.) Pods Using Different Solvents

Extracts derived from the Ceratonia siliqua L. (carob) tree have been widely studied for their ability to prevent many diseases mainly due to the presence of polyphenolic compounds. In this study, we explored, for the first time, the anti-cancer properties of Cypriot carobs. We produced extracts from ripe and unripe whole carobs, pulp and seeds using solvents with different polarities. We measured the ability of the extracts to inhibit proliferation and induce apoptosis in cancer and normal immortalized breast cells, using the MTT assay, cell cycle analysis and Western Blotting. The extracts' total polyphenol content and anti-oxidant action was evaluated using the Folin-Ciocalteu method and the DPPH assay. Finally, we used LC-MS analysis to identify and quantify polyphenols in the most effective extracts. Our results demonstrate that the anti-proliferative capacity of carob extracts varied with the stage of carob maturity and the extraction solvent. The Diethyl-ether and Ethyl acetate extracts derived from the ripe whole fruit had high Myricetin content and also displayed specific activity against cancer cells. Their mechanism of action involved caspase-dependent and independent apoptosis. Our results indicate that extracts from Cypriot carobs may have potential uses in the development of nutritional supplements and pharmaceuticals.

Phloretin Alleviates Arsenic Trioxide-Induced Apoptosis of H9c2 Cardiomyoblasts via Downregulation in Ca2+/Calcineurin/NFATc Pathway and Inflammatory Cytokine Release

Arsenic trioxide (ATO) is among the first-line chemotherapeutic drugs for treating acute promyelocytic leukemia patients, but its clinical use is hampered due to cardiotoxicity. The present investigation unveils the mechanism underlying ATO-induced oxidative stress that promotes calcineurin (a ubiquitous Ca²⁺/calmodulin-dependent serine/threonine phosphatase expressed only during sustained Ca²⁺ elevation) expression, inflammatory cytokine release and apoptosis in H9c2 cardiomyoblasts, and its possible modulation with phloretin (PHL, an antioxidant polyphenol present in apple peel). ATO caused Ca²⁺ overload resulting in elevated expression of calcineurin and its downstream transcriptional effector NFATc causing the release of cytokines such as IL-2, IL-6, MCP-1, IFN-γ, and TNF-α in H9c2 cardiomyoblast. There was a visible increase in the nuclear fraction of NF-κB and ROS-mediated apoptotic cell death. The expression levels of cardiac-specific genes (troponin, desmin, and caveolin-3) and genes of the apoptotic signaling pathway (BCL-2, BAX, IGF1, AKT, ERK1, -2, RAF1, and JNK) in response to ATO and PHL were studied. The putative binding mode and the potential ligand-target interactions of PHL with calcineurin using docking software (Autodock and iGEMDOCKv2) showed the high binding affinity of PHL to calcineurin. PHL co-treatment significantly reduced Ca²⁺ influx and normalized the expression of calcineurin, NFATc, NF-κB, and other cytokines. PHL co-treatment resulted in activation of BCL-2, IGF1, AKT, RAF1, ERK1, and ERK2 and inhibition of BAX and JNK. Overall, these results revealed that PHL has a protective effect against ATO-induced apoptosis and we propose calcineurin as a druggable target for the interaction of PHL in ATO cardiotoxicity in H9c2 cells.

Mechanisms and Molecular Targets of Artemisinin in Cancer Treatment

The major problems with cancer therapy are drug-induced side effects. There is an urgent need for safe anti-tumor drugs. Artemisinin is a Chinese herbal remedy for malaria with efficacy and safety. However, several studies reported that artemisinin causes neurotoxicity and cardiotoxicity in animal models. Recently, nanostructured drug delivery systems have been designed to improve therapeutic efficacy and reduce toxicity. Artemisinin has been reported to show anticancer properties. The anticancer effects of artemisinin appear to be mediated by inducing cell cycle arrest, promoting ferroptosis and autophagy, inhibiting cell metastasis. Therefore, the review is to concentrate on mechanisms and molecular targets of artemisinin as anti-tumor agents. We believe these will be important topics in realizing the potential of artemisinin and its derivatives as potent anticancer agents.