Synergistic apoptotic effect of celecoxib and luteolin on breast cancer cells

Progress, pharmacokinetics and future perspectives of luteolin modulating signaling pathways to exert anticancer effects: A review

Luteolin (3, 4, 5, 7-tetrahydroxyflavone) are natural flavonoids widely found in vegetables, fruits and herbs, with anti-tumor, anti-inflammatory and antioxidant effects, and also play an anti-cancer effect in various cancers such as lung, breast, prostate, and liver cancer, etc. Specifically, the anti-cancer mechanism includes regulation of various signaling pathways to induce apoptosis of tumor cells, inhibition of tumor cell proliferation and metastasis, anti-angiogenesis, regulation of immune function, synergistic anti-cancer drugs and regulation of reactive oxygen species levels of tumor cells. Specific anti-cancer mechanisms include regulation of various signaling pathways to induce apoptosis, inhibition of tumor cell proliferation and metastasis, anti-angiogenesis, reversal of epithelial-mesenchymal transition, regulation of immune function, synergism with anti-cancer drugs and regulation of reactive oxygen species levels in tumor cells. This paper integrates the latest cutting-edge research on luteolin and combines it with the prospect of future clinical applications, aiming to explore the mechanism of luteolin exerting different anticancer effects through the regulation of different signaling pathways, so as to provide a practical theoretical basis for the use of luteolin in clinical treatment and hopefully provide some reference for the future research direction of luteolin.

Contribution of non-steroidal anti-inflammatory drugs to breast cancer treatment: In vitro and in vivo studies

Chronic inflammation plays a crucial role in carcinogenesis. High levels of serum prostaglandin E2 and tissue overexpression of cyclooxygenase-2 (COX-2) have been described in breast, urinary, colorectal, prostate, and lung cancers as being involved in tumor initiation, promotion, progression, angiogenesis, and immunosuppression. Non-steroidal anti-inflammatory drugs (NSAIDs) are prescribed for several medical conditions to not only decrease pain and fever but also reduce inflammation by inhibiting COX and its product synthesis. To date, significant efforts have been made to better understand and clarify the interplay between cancer development, inflammation, and NSAIDs with a view toward addressing their potential for cancer management. This review provides readers with an overview of the potential use of NSAIDs and selective COX-2 inhibitors for breast cancer treatment, highlighting pre-clinical in vitro and in vivo studies employed to evaluate the efficacy of NSAIDs and their use in combination with other antineoplastic drugs.

Application of Luteolin in Neoplasms and Nonneoplastic Diseases

Researchers are amazed at the multitude of biological effects of 3',4',5,7-tetrahydroxyflavone, more commonly known as luteolin, as it simultaneously has antioxidant and pro-oxidant, as well as antimicrobial, anti-inflammatory, and cancer-preventive, properties. The anticancer properties of luteolin constitute a mosaic of pathways due to which this flavonoid influences cancer cells. Not only is it able to induce apoptosis and inhibit cancer cell proliferation, but it also suppresses angiogenesis and metastasis. Moreover, luteolin succeeds in cancer cell sensitization to therapeutically induced cytotoxicity. Nevertheless, apart from its promising role in chemoprevention, luteolin exhibits numerous potential utilizations in patients with conditions other than neoplasms, which include inflammatory skin diseases, diabetes mellitus, and COVID-19. This review aims to present the multidimensionality of the luteolin's impact on both neoplastic and nonneoplastic diseases. When it comes to neoplasms, we intend to describe the complexity of the molecular mechanisms that underlay luteolin's anticancer effectiveness, as well as to prove the usefulness of integrating this flavonoid in cancer therapy via the analysis of recent research on breast, colon, and lung cancer. Regarding nonneoplastic diseases, this review aims to emphasize the importance of researching the potential of luteolin in areas such as diabetology, virology, and dermatology as it summarizes the most important discoveries in those fields regarding its application.

Concomitant effects of paclitaxel and celecoxib on genes involved in apoptosis of triple-negative metastatic breast cancer cells

Although triple-negative breast cancer accounts for less than one-fifth of breast cancers, it has a higher rate of metastasis and mortality. This study investigated the effects of combination treatment with paclitaxel and celecoxib on the expression of genes involved in the apoptosis of triple-negative metastatic breast cancer cells. MDA-MB-231 cells were cultured and then treated with certain concentrations of celecoxib (CLX), paclitaxel (PTX), and combination of them for 24 and 48 h. Cell viability was assessed by the MTT method. The real-time PCR method was utilized to assess the expression level of the genes involved in apoptosis. Western blotting was used for evaluating protein expression. IC50 values for CLX and PTX were 73.95 μM and 3.15 μM, respectively. The results demonstrated that PTX, CLX, and PTX + CLX significantly (p < 0.05) reduced cell viability. The comparison of combination treatment with PTX showed a significant increase in caspase 3 gene expression at both time points, in Bax gene expression after 48 h, and a remarkable decrease in Bcl-2 gene expression at both times. Western blotting results were in line with genes' expression. These findings indicate that a combination of PTX and CLX results in a significantly more reduction in cell viability of breast cancer cells. In addition, it seems CLX may be an effective agent in regulating the expression level of caspase 3, Bax, and Bcl-2 when combined with PTX.

Therapeutic Potential of Luteolin on Cancer

Cancer is a global concern, as the rate of incidence is increasing each year. The challenges related to the current chemotherapy drugs, such as the concerns related to toxicity, turn to cancer therapeutic research to discover alternative therapy strategies that are less toxic to normal cells. Among those studies, the use of flavonoids—natural compounds produced by plants as secondary metabolites for cancer therapy—has been a hot topic in cancer treatment. Luteolin, a flavonoid that has been present in many fruits, vegetables, and herbs, has been identified to exhibit numerous biological activities, including anti-inflammatory, antidiabetic, and anticancer properties. The anticancer property of Luteolin has been extensively researched in many cancer types and has been related to its ability to inhibit tumor growth by targeting cellular processes such as apoptosis, angiogenesis, migration, and cell cycle progression. It achieves this by interacting with various signaling pathways and proteins. In the current review, the molecular targets of Luteolin as it exerts its anticancer properties, the combination therapy that includes Luteolin with other flavonoids or chemotherapeutic drugs, and the nanodelivery strategies for Luteolin are described for several cancer types.

Synergistic Combination of Luteolin and Asiatic Acid on Cervical Cancer In Vitro and In Vivo

Cervical cancer is an important issue globally because it is the second most common gynecological malignant tumor and conventional treatment effects have been shown to be limited. Lut and AsA are plant-derived natural flavonoid and triterpenoid products that have exhibited anticancer activities and can modulate various signaling pathways. Thus, the aim of the present study was to evaluate whether Lut combined with AsA could enhance the anticancer effect to inhibit cervical cancer cell proliferation and examine the underlying molecular mechanisms in vitro and in vivo. The results of a CCK-8 assay showed that Lut combined with AsA more effectively inhibited the proliferation of CaSki and HeLa cells than Lut or AsA treatment alone. Lut combined with AsA caused apoptosis induction and sub-G1-phase arrest in CaSki and HeLa cells, as confirmed by flow cytometry, mitoROS analysis, antioxidant activity measurement and western blot assay. In addition, Lut combined with AsA significantly inhibited the cell migration ability of CaSki and HeLa cells in a wound-healing assay. Furthermore, Lut combined with AsA induced apoptosis and inhibited migration through downregulated PI3K/AKT (PI3K, AKT and p70S6K), JNK/p38 MAPK and FAK (integrin β1, paxillin and FAK) signaling and upregulated ERK signaling. In an in vivo study, Lut combined with AsA markedly inhibited cervical cancer cell-derived xenograft tumor growth. Collectively, the present study showed that Lut combined with AsA may be used as an anticancer agent to improve the prognosis of cervical cancer. Indeed, with additional research to develop standardized dosages, Lut and AsA combination therapy could also be applied in clinical medicine.

Luteolin, a Potent Anticancer Compound: From Chemistry to Cellular Interactions and Synergetic Perspectives

Increasing rates of cancer incidence and the toxicity concerns of existing chemotherapeutic agents have intensified the research to explore more alternative routes to combat tumor. Luteolin, a flavone found in numerous fruits, vegetables, and herbs, has exhibited a number of biological activities, such as anticancer and anti-inflammatory. Luteolin inhibits tumor growth by targeting cellular processes such as apoptosis, cell-cycle progression, angiogenesis and migration. Mechanistically, luteolin causes cell death by downregulating Akt, PLK-1, cyclin-B1, cyclin-A, CDC-2, CDK-2, Bcl-2, and Bcl-xL, while upregulating BAX, caspase-3, and p21. It has also been reported to inhibit STAT3 signaling by the suppression of STAT3 activation and enhanced STAT3 protein degradation in various cancer cells. Therefore, extensive studies on the anticancer properties of luteolin reveal its promising role in chemoprevention. The present review describes all the possible cellular interactions of luteolin in cancer, along with its synergistic mode of action and nanodelivery insight.

The Potential of Plant-Derived Extracts and Compounds to Augment Anticancer Effects of Chemotherapeutic Drugs

Plant extracts comprise a complex mixture of natural compounds with diverse biological activities including anticancer activities. This has made the use of plant extracts a trending strategy in cancer treatment. In addition, plants' active constituents such as polyphenols could confer protective effects on normal cells against damage by free radicals as well as lessen the toxicity of chemotherapeutic drugs. Recently, many emerging studies revealed the combinatory uses of plant extracts and individual therapeutic compounds that could be a promising panacea in hampering multiple signaling pathways involved in cancer development and progression. Besides enhancing the therapeutic efficacy, this has also been proven to reduce the dosage of chemotherapeutic drugs used, and hence overcome multiple drug resistance and minimize treatment side effects. Notably, combined use of plant extracts with chemotherapeutics drugs was shown to enhance anticancer effects through modulating various signaling pathways, such as P13K/AKT, NF-κB, JNK, ERK, WNT/β-catenin, and many more. Hence, this review aims to comprehensively summarize both In Vitro and In Vivo mechanisms of actions of well-studied plant extracts, such as Ganoderma Lucidum, Korean red ginseng, Garcinia sp., curcumin, and luteolin extracts in augmenting anticancer properties of the conventional chemotherapeutic drugs from an extensive literature search of recent publications.

Orobanche crenata Forssk. Extract Affects Human Breast Cancer Cell MCF-7 Survival and Viral Replication

BACKGROUND

Breast cancer (BC) is the leading cause of death worldwide. The severity of BC strictly depends on the molecular subtype. The less aggressive hormone-positive subtype is treated with adjuvant endocrine therapy (AET), which causes both physical and psychological side effects. This condition strongly impacts the adherence and persistence of AET among oncologic patients. Moreover, viral infections also constitute a serious problem for public health. Despite their efficacy, antiviral agents present several therapeutic limits. Accordingly, in the present work, we investigated the antitumor and antiviral activities of Orobanche crenata Forssk. (O. crenata), a parasitic plant, endemic to the Mediterranean basin, traditionally known for its beneficial properties for human health.

METHODS

The MTT assay was carried out to evaluate the cytotoxic effect of O. crenata leaf extract (OCLE) on human breast cancer cells (MCF-7 and MDA-MB-231) and the primary HFF-1 cell line. The lactic dehydrogenase (LDH) assay was performed on MCF-7 cells to analyze necrotic cell death. The antioxidant effect of OCLE was evaluated by intracellular determination of the reactive oxygen species and thiol groups, by DPPH and ABTS assays. The antiviral activity of OCLE was determined against Poliovirus 1, Echovirus 9, Human respiratory syncytial virus, Adenovirus type 2 and type 5, Coxsackievirus B1 (CoxB1) and B3 (CoxB3), Herpes simplex type 1 (HSV-1) and type 2 (HSV-2), and β-Coronavirus by the plaque reduction assay.

RESULTS

The extract, after 24 h of incubation, did not affect MDA-MB-231 and HFF-1 cell viability. However, at the same time point, it showed a dose-dependent inhibitory effect on MCF-7 cells, with an increase in LDH release. OCLE exhibited free radical scavenging activity and significantly increased non-protein thiol levels in MCF-7 cells. OCLE effectively inhibited HSV-1, HSV-2, CoxB1, and CoxB3 replication.

CONCLUSIONS

The overall results showed an interesting inhibitory effect of OCLE on both MCF-7 cell survival and viral replication.

Orientin, a Bio-Flavonoid from Trigonella hamosa L., Regulates COX-2/PGE-2 in A549 Cell Lines via miR-26b and miR-146a

Cancer is a severe health condition and considered one of the major healthcare issues and is in need of innovative strategy for a cure. The current study aimed to investigate the chemical profile of Trigonella hamosa L. and a potential molecular approach to explain its regulation in cancer progression through an inflammatory mediator (COX-2) in A549 non-small lung cancer cell lines via in silico, mechanistic and molecular aspects. T. hamosa was extracted and then subjected to a CCK-8 cell viability assay in different cancer cell lines including MDA-MB-231, A549 and HCT-116. Total extract was subjected to several chromatographic techniques to yield orientin (OT); the structure was elucidated by inspection of NMR spectroscopic data. To achieve anticancer effects of OT, a cell viability assay using a CCK-8 kit, immunoprecipitation by Western blot, cell migration using a wound healing assay, cell invasion using a Matrigel-Transwell assay, apoptosis by AO/EB dual staining, flow cytometric analysis and DAPI staining, a silenced COX-2 model to determine PGE-2 production and real-time PCR and Western blot of BCL-2, CYP-1A1, iNOS and COX-2 markers were carried out. The results demonstrated that OT decreased the cell proliferation and controlled cell migration and invasive properties. OT destabilized the COX-2 mRNA and downregulated its expression in A549 cell lines. Virtual binding showed interaction (binding energy −10.43) between OT and COX-2 protein compared to the selective COX-2 inhibitor celecoxib (CLX) (binding energy −9.4). The OT-CLX combination showed a superior anticancer effect. The synergistic effect of OT-CLX combination was noticed in controlling the migration and invasion of A549 cell lines. OT-CLX downregulated the expression of BCL-2, iNOS and COX-2 and activated the proapoptotic gene CYP-1A1. OT mitigated the COX-2 expression via upregulation of miR-26b and miR-146a. Interestingly, COX-2-silenced transfected A549 cells exhibited reduced expression of miR-26b and miR-146a. The findings confirmed the direct interaction of OT with COX-2 protein. PGE-2 expression was quantified in both naïve and COX-2-silenced A549 cells. OT downregulated the release of PGE-2 in both tested conditions. These results confirmed the regulatory effect of OT on A549 cell growth in a COX-2-dependent manner. OT activated apoptosis via activation of CYP-1A1 expression in an independent manner. These results revealed that the OT-CLX combination could serve as a potential synergistic treatment for effective inflammatory-mediated anticancer strategies.

Influence of Olive Oil and Its Components on Breast Cancer: Molecular Mechanisms

Breast cancer is the most frequent malignant neoplasia and a leading cause of mortality in women worldwide. The Mediterranean diet has been proposed as a healthy dietary pattern with protective effects in several chronic diseases, including breast cancer. This diet is characterized by the consumption of abundant plant foods and olive oil as the principal source of fat, which is considered one of the main components with potential antioxidant, anti-inflammatory and anticancer effects. Extra-virgin olive oil (EVOO) has several bioactive compounds, mainly including monounsaturated fatty acids, triterpenes and polyphenols, such as phenolic alcohols (e.g., hydroxytyrosol), secoiridoids (e.g., oleuropein and oleocanthal), lignans (e.g., pinoresinol) or flavonoids (e.g., luteolin). While epidemiological evidence is still limited, experimental in vivo and in vitro data have shown a protective effect of this oil and its compounds on mammary carcinogenesis. Such effects account through complex and multiple mechanisms, including changes in epigenetics, transcriptome and protein expression that modulate several signaling pathways. Molecular targets of EVOO compounds have a role in the acquisition of cancer hallmarks. Although further research is needed to elucidate their beneficial effects on human prevention and progression of the disease, evidence points to EVOO in the context of the Mediterranean diet as a heathy choice, while EVOO components may be promising adjuvants in anticancer strategies.

Hepatoprotective Effects of Bioflavonoid Luteolin Using Self-Nanoemulsifying Drug Delivery System

Luteolin (LUT) is a natural pharmaceutical compound that is weakly water soluble and has low bioavailability when taken orally. As a result, the goal of this research was to create self-nanoemulsifying drug delivery systems (SNEDDS) for LUT in an attempt to improve its in vitro dissolution and hepatoprotective effects, resulting in increased oral bioavailability. Using the aqueous phase titration approach and the creation of pseudo-ternary phase diagrams with Capryol-PGMC (oil phase), Tween-80 (surfactant), and Transcutol-HP (co-emulsifier), various SNEDDS of LUT were generated. SNEDDS were assessed for droplet size, polydispersity index (PDI), zeta potential (ZP), refractive index (RI), and percent of transmittance (percent T) after undergoing several thermodynamic stability and self-nanoemulsification experiments. When compared to LUT suspension, the developed SNEDDS revealed considerable LUT release from all SNEDDS. Droplet size was 40 nm, PDI was <0.3, ZP was -30.58 mV, RI was 1.40, percent T was >98 percent, and drug release profile was >96 percent in optimized SNEDDS of LUT. For in vivo hepatoprotective testing in rats, optimized SNEDDS was chosen. When compared to LUT suspension, hepatoprotective tests showed that optimized LUT SNEDDS had a substantial hepatoprotective impact. The findings of this investigation suggested that SNEDDS could improve bioflavonoid LUT dissolution rate and therapeutic efficacy.

Old and New Players of Inflammation and Their Relationship With Cancer Development

Pathogens or genotoxic agents continuously affect the human body. Acute inflammatory reaction induced by a non-sterile or sterile environment is triggered for the efficient elimination of insults that caused the damage. According to the insult, pathogen-associated molecular patterns, damage-associated molecular patterns, and homeostasis-altering molecular processes are released to facilitate the arrival of tissue resident and circulating cells to the injured zone to promote harmful agent elimination and tissue regeneration. However, when inflammation is maintained, a chronic phenomenon is induced, in which phagocytic cells release toxic molecules damaging the harmful agent and the surrounding healthy tissues, thereby inducing DNA lesions. In this regard, chronic inflammation has been recognized as a risk factor of cancer development by increasing the genomic instability of transformed cells and by creating an environment containing proliferation signals. Based on the cancer immunoediting concept, a rigorous and regulated inflammation process triggers participation of innate and adaptive immune responses for efficient elimination of transformed cells. When immune response does not eliminate all transformed cells, an equilibrium phase is induced. Therefore, excessive inflammation amplifies local damage caused by the continuous arrival of inflammatory/immune cells. To regulate the overstimulation of inflammatory/immune cells, a network of mechanisms that inhibit or block the cell overactivity must be activated. Transformed cells may take advantage of this process to proliferate and gradually grow until they become preponderant over the immune cells, preserving, increasing, or creating a microenvironment to evade the host immune response. In this microenvironment, tumor cells resist the attack of the effector immune cells or instruct them to sustain tumor growth and development until its clinical consequences. With tumor development, evolving, complex, and overlapping microenvironments are arising. Therefore, a deeper knowledge of cytokine, immune, and tumor cell interactions and their role in the intricated process will impact the combination of current or forthcoming therapies.

Luteolin-Loaded Elastic Liposomes for Transdermal Delivery to Control Breast Cancer: In Vitro and Ex Vivo Evaluations

The study aimed to prepare and optimize luteolin (LUT)-loaded transdermal elastic liposomes (LEL1-LEL12), followed by in vitro and ex vivo evaluations of their ability to control breast cancer. Various surfactants (Span 60, Span 80, and Brij 35), and phosphatidyl choline (PC) as a lipid, were used to tailor various formulation as dictated by “Design Expert^® software (DOE). These were characterized for size, polydispersity index (PDI), and zeta potential. The optimized formulation (OLEL1) was selected for comparative investigations (in vitro and ex vivo) against lipo (conventional liposomes) and drug suspension (DS). Moreover, the in vitro anticancer activity of OLEL1 was compared against a control using MCF-7 cell lines. Preliminary selection of the suitable PC: surfactant ratio for formulations F1–F9 showed relative advantages of Span 80. DOE suggested two block factorial designs with four center points to identify the design space and significant factors. OLEL1 was the most robust with high functional desirability (0.95), minimum size (202 nm), relatively high drug release, increased drug entrapment (92%), and improved permeation rate (~3270 µg/cm²) as compared with liposomes (~1536 µg/cm²) over 24 h. OLEL1 exhibited a 6.2- to 2.9-fold increase in permeation rate as compared with DS (drug solution). The permeation flux values of OLEL1, and lipo were found to be 136.3, 64 and 24.3 µg/h/cm², respectively. The drug disposition values were 670 µg, 473 µg and 148 µg, for OLEL1, lipo and DS, respectively. Thus, ex vivo parameters were significantly better for OLEL1 compared with lipo and DS which is attributed to the flexibility and deformability of the optimized formulation. Furthermore, OLEL1 was evaluated for anticancer activity and showed maximized inhibition as compared with DS. Thus, elastic liposomes may be a promising approach for improved transdermal delivery of luteolin, as well as enhancing its therapeutic efficacy in controlling breast cancer.

Research Progress in Flavonoids as Potential Anticancer Drug Including Synergy with Other Approaches

BACKGROUND

In chemotherapy for cancer, conventional drugs aim to target the rapidly growing and dividing cells at the early stages. However, at an advanced stage, cancer cells become less susceptible because of the multidrug resistance and the recruitment of alternative salvage pathways for their survival. Besides, owing to target non-selectivity, healthy proliferating cells also become vulnerable to the damage. The combination therapies offered using flavonoids to cure cancer not only exert an additive effect against cancer cells by targetting supplementary cell carnage pathways but also hampers the drug resistance mechanisms. Thus, the review aims to discuss the potential and pharmacokinetic limitations of flavonoids in cancer treatment. Further successful synergistic studies reported using flavonoids to treat cancer has been described along with potential drug delivery systems.

METHODS

A literature search was done by exploring various online databases like Pubmed, Scopus, and Google Scholar with the specific keywords like "Anticancer drugs", "flavonoids", "oncology research", and "pharmacokinetics".

RESULTS

Dietary phytochemicals, mainly flavonoids, hinder cell signalling responsible for multidrug resistance and cancer progression, primarily targeting cancer cells sparing normal cells. Such properties establish flavonoids as a potential candidate for synergistic therapy. However, due to low absorption and high metabolism rates, the bioavailability of flavonoids becomes a challenge. Such challenges may be overcome using novel approaches like derivatization, and single or co-delivery nano-complexes of flavonoids with conventional drugs. These new approaches may improve the pharmacokinetic and pharmacodynamic of flavonoids.

CONCLUSION

This review highlights the application of flavonoids as a potential anticancer phytochemical class in combination with known anti-cancer drugs/nanoparticles. It also discusses flavonoid's pharmacokinetics and pharmacodynamics issues and ways to overcome such issues. Moreover, it covers successful methodologies employed to establish flavonoids as a safe and effective phytochemical class for cancer treatment.

Luteolin-Fabricated ZnO Nanostructures Showed PLK-1 Mediated Anti-Breast Cancer Activity

The present work describes a facile and convenient procedure for synthesizing zinc oxide nanoparticles using luteolin isolated from Eclipta alba plant (L-ZnONPs) at room temperature. The formation of as-grown L-ZnONPs was confirmed by X-ray diffraction analysis (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HR-TEM), and selected area electron diffraction (SAED). The Wurtzite structure of ZnO was observed by its hexagonal phases in diffraction patterns. The SEM images revealed the different sizes and morphologies of L-ZnONPs, with diameters between 12 and 25 nm. The HR-TEM result showed that the inter-planar distance between two lattice fringes was 0.262 nm, which coincides with the d-spacing of (002) and (101) lattice planes of the as-obtained material. The anticancer activity of L-ZnONPs against the breast cancer cell line MCF-7 was greater as compared to that of luteolin or ZnO alone. The mechanistic evaluation of such an activity carried out using in silico methods suggested that the anti-breast cancer activity of L-ZnONPs was mediated by polo-like kinase 1 (PLK1) proteins.

A Network Pharmacology Study on the Molecular Mechanisms of FDY003 for Breast Cancer Treatment

Herbal medicines have drawn considerable attention with regard to their potential applications in breast cancer (BC) treatment, a frequently diagnosed malignant disease, considering their anticancer efficacy with relatively less adverse effects. However, their mechanisms of systemic action have not been understood comprehensively. Based on network pharmacology approaches, we attempted to unveil the mechanisms of FDY003, an herbal drug comprised of Lonicera japonica Thunberg, Artemisia capillaris Thunberg, and Cordyceps militaris, against BC at a systemic level. We found that FDY003 exhibited pharmacological effects on human BC cells. Subsequently, detailed data regarding the biochemical components contained in FDY003 were obtained from comprehensive herbal medicine-related databases, including TCMSP and CancerHSP. By evaluating their pharmacokinetic properties, 18 chemical compounds in FDY003 were shown to be potentially active constituents interacting with 140 BC-associated therapeutic targets to produce the pharmacological activity. Gene ontology enrichment analysis using g:Profiler indicated that the FDY003 targets were involved in the modulation of cellular processes, involving the cell proliferation, cell cycle process, and cell apoptosis. Based on a KEGG pathway enrichment analysis, we further revealed that a variety of oncogenic pathways that play key roles in the pathology of BC were significantly enriched with the therapeutic targets of FDY003; these included PI3K-Akt, MAPK, focal adhesion, FoxO, TNF, and estrogen signaling pathways. Here, we present a network-perspective of the molecular mechanisms via which herbal drugs treat BC.

COX-2 promotes mammary adipose tissue inflammation, local estrogen biosynthesis, and carcinogenesis in high-sugar/fat diet treated mice

Obesity is a major risk factor for breast cancer, especially in post-menopausal women. In the breast tissue of obese women, cyclooxygenase-2 (COX-2)-dependent prostaglandin E2 (PGE2) production has been correlated with inflammation and local estrogen biosynthesis via aromatase. Using a mouse model of 7,12-dimethylbenz[a]anthracene/medroxyprogesterone-acetate (DMBA/MPA)-induced carcinogenesis, we demonstrated that an obesogenic diet promotes mammary tissue inflammation and local estrogen production, and accelerates mammary tumor formation in a COX-2-dependent manner. High-sugar/fat (HSF) diet augmented the levels of the pro-inflammatory mediators MCP-1, IL-6, COX-2, and PGE2 in mammary tissue, and this was accompanied by crown-like structures of breast (CLS-B) formation and aromatase/estrogen upregulation. Treatment with a COX-2 selective inhibitor, etoricoxib, decreased PGE2, IL-6, MCP-1, and CLS-B formation as well as reduced aromatase protein and estrogen levels in the mammary tissue of mice fed a HSF diet. Etoricoxib-treated mice showed increased latency and decreased incidence of mammary tumors, which resulted in prolonged animal survival when compared to HSF diet alone. Inhibition of tumor angiogenesis also seemed to account for the prolonged survival of COX-2 inhibitor-treated animals. In conclusion, obesogenic diet-induced COX-2 is sufficient to trigger inflammation, local estrogen biosynthesis, and mammary tumorigenesis.

Plant-Derived Natural Products in Cancer Research: Extraction, Mechanism of Action, and Drug Formulation

Cancer is one of the main causes of death globally and considered as a major challenge for the public health system. The high toxicity and the lack of selectivity of conventional anticancer therapies make the search for alternative treatments a priority. In this review, we describe the main plant-derived natural products used as anticancer agents. Natural sources, extraction methods, anticancer mechanisms, clinical studies, and pharmaceutical formulation are discussed in this review. Studies covered by this review should provide a solid foundation for researchers and physicians to enhance basic and clinical research on developing alternative anticancer therapies.

Aspirin potentiates celecoxib-induced growth inhibition and apoptosis in human non-small cell lung cancer by targeting GRP78 activity

Background:

Aspirin has recently emerged as an anticancer drug, but its therapeutic effect on lung cancer has been rarely reported, and the mechanism of action is still unclear. Long-term use of celecoxib in large doses causes serious side effects, and it is necessary to explore better ways to achieve curative effects. In this study, we evaluated the synergistic anticancer effects of celecoxib and aspirin in non-small cell lung cancer (NSCLC) cells.

Methods:

In vitro, we evaluated the combined effects of celecoxib (40 μM) and aspirin (8 mM) on cell apoptosis, cell cycle distribution, cell proliferation, cell migration and signaling pathways. Furthermore, the effect of aspirin (100 mg/kg body weight) and celecoxib (50 mg/kg body weight) on the growth of xenograft tumors was explored in vivo.

Results:

Our data suggest that cancer sensitivity to combined therapy using low concentrations of celecoxib and aspirin was higher than that of celecoxib or aspirin alone. Further research showed that the anti-tumor effect of celecoxib combined with aspirin was mainly produced by activating caspase-9/caspase-3, arresting cell cycle and inhibiting the ERK-MAPK signaling pathway. In addition, celecoxib alone or in combination with aspirin inhibited the migration and invasion of NSCLC cells by inhibiting MMP-9 and MMP-2 activity levels. Moreover, we identified GRP78 as a target protein of aspirin in NSCLC cells. Aspirin induced an endoplasmic reticulum stress response by inhibiting GRP78 activity. Furthermore, combination therapy also exhibited a better inhibitory effect on tumor growth in vivo.

Conclusions:

Our study provides a rationale for further detailed preclinical and potential clinical studies of the combination of celecoxib and aspirin for NSCLC therapy.

Interaction of apigenin-7-O-glucoside with pyrimethamine against Toxoplasma gondii growth

Apigenin-7-O-glucoside, a flavonoid glucoside known to inhibit cancer cell growth, fungi growth, both intra and extracellular reactive oxygen species generation, causing cell arrest and damage to the plasma membrane, was tested alone or in combination with a dihydrofolate inhibitor (pyrimethamine) against Toxoplasma gondii (T. gondii) growth. The anti-T. gondii activity was carried out using a high throughput antiparasitic drug screening cell-based assay known as 2-(2-methoxy-4-nitrophenyl)-3-(4-nitrophenyl)-5-(2,4-disulfophenyl)-2H tetrazolium, monosodium salt (WST-8) and fluorescence plate reader. The 50% effective concentration inhibition and 95% confidence interval values for individual and combination treatments against T. gondii were 0.80 (0.38-1.29) µg/mL, 1.05 (0.275-2.029) µg/mL, and 0.40 (0-1.06) µg/mL for apigenin-7-O-glucoside, pyrimethamine, and apigenin-7-O-glucoside plus pyrimethamine, respectively. Interestingly, the apigenin-7-O-glucoside plus pyrimethamine combination showed an additive inhibition effect against T. gondii growth in vitro using the fractional inhibitory concentration index method. It was discovered that the apigenin-7-O-glucoside combination with pyrimethamine had a high selectivity index 62.5, which implies 62-fold inhibition activity against the parasite versus human foreskin fibroblast cell cytotoxicity. This new combination hit is novel and will have the potential for future effective, safe, and less costly anti-Toxoplasma drug development, if its in vivo activity shows similar findings.

Combination of celecoxib and calyculin-A inhibits epithelial-mesenchymal transition in human oral cancer cells

Expression of cyclo-oxygenase-2 (COX-2) and protein phosphatase 2A (PP2A) deactivation occurs frequently in oral squamous cell carcinoma (OSCC). We initially assessed COX-2 and PP2A protein expression in OSCC specimens using immunohistochemical (IHC) staining and western blot analysis. We found strong COX-2 and phosphorylated PP2A (p-PP2A) expression in OSCC samples. No significant difference in total PP2A expression was observed between cancer and nontumor tissues. The effect of combining COX-2 inhibitor and celecoxib (CXB) with the PP2A inhibitor, calyculin-A (CLA) on the OSCC cell line, HSC3, was evaluated in vitro. We found that a combination of 1 nM CLA and 50 µM CXB significantly inhibited cell viability, and migration and invasion of HSC3 cells. Western blots for AKT, p-AKT, ERK, p-ERK, E-cadherin, vimentin and β-catenin were conducted after treatment with CXB and/or CLA. Increased E-cadherin and decreased β-catenin expression were found in CXB or CLA treated hsc-3 cells, whereas the combined CXB and CLA treatment showed no difference in E-cadherin or β-catenin expression. Our findings suggest that CLA alone was more effective than CXB alone, but not in the combined drug treatment.

Selective COX-2 inhibitors as anticancer agents: a patent review (2014-2018)

INTRODUCTION

COX-2 is a key enzyme in the process of prostaglandins (PGs) synthesis. The products of this enzyme could play a major role as the mediators of the inflammatory response and some other medical states such as cancer. The design and synthesis of novel selective COX-2 inhibitors have always been attractive to researchers. This review discusses the structures of novel COX-2 inhibitors synthesized during the last five years and describes their efficacy as anticancer agents.

AREAS COVERED

It is well established that COX-2 is overexpressed in many different cancers and treatment with selective COX-2 inhibitors could relieve their symptoms and limit their adverse sequences.

EXPERT OPINION

The diversity of selective COX-2 inhibitors is mainly related to the types of scaffolds. Monocyclic, bicyclic, tricyclic, and acyclic scaffolds with different pharmacological effects and toxicological profiles could be found in the family of selective COX-2 inhibitors. The great interest of the researchers in this field is due to the importance of selective COX-2 inhibitors as a relatively safe and effective set of compounds which could present different properties such as antirheumatic, anti-inflammatory, antiplatelet, anti-Alzheimer's disease, anti-Parkinson's disease, and anticancer.

Apoptosis induced by luteolin in breast cancer: Mechanistic and therapeutic perspectives

BACKGROUND

Breast cancer is worldwide commonly found malignancy in women and effective treatment is regarded as a huge clinical challenge even in the presence of several options. Extensive literature is available that demonstrating polyphenols, the richly introduce phytopharmaceuticals as anticancer agents. Among these polyphenols, resveratrol, silibinin, quercetin, genistein, curcumin reported to have an awesome potential against breast cancer. However, till now no comprehensive survey found about the anticarcinogenic properties of luteolin against breast cancer.

SCOPE AND APPROACH

This review targeted the available literature on luteolin in the treatment of breast cancer, effects in combination with other anticancer drugs with possible mechanisms.

KEY FINDINGS AND CONCLUSION

An outstanding therapeutic potential of luteolin in the treatment of breast cancer has been recorded not just as a chemopreventive and chemotherapeutic agent yet complemented by its synergistic effects with other anticancer therapies such as cyclophosphamide, doxorubicin, and NSAID such as celecoxib, and possible underlying mechanisms. Ideally, this review will open new dimensions for luteolin as an effective and safe therapeutic agent in diminishing breast cancer.

Heat processing effect of luteolin on anti-metastasis activity of human glioblastoma cells U87

Among the flavonoïds, luteolin is a flavone that has been identified in many plants. It is known for its apoptotic potential with damage to DNA and cell cycle blockage. Many studies have shown that luteolin has anti-oxidant, anti-inflammatory, and anti-cancer activities. However, it is known that heat treatment (boiling, cooking, and treating with microwaves …) can influence the structure of flavonoïds, which often leads to changes in their activities. The present study was conducted to study the effect of heated luteolin on anti-tumor activity of glioblastoma cells U87. Glioblastoma cell viability was evaluated by MTT assay. Adhesion assay was performed on different protein matrices (collagen type 1, vitronectin, fibronectin, and poly-L-lysine); migration assay was determined by modified Boyden chambers and videomicroscopy, and finally, angiogenesis was tested in vitro by capillary network formation on Matrigel™. The results obtained show that the thermal treatment significantly reduces its cytotoxic activity and ability to inhibit cell adhesion to different protein matrices. It was also found that the heat processed significantly reduced the ability of luteolin to inhibit cell migration, cell invasion, and endothelial cell angiogenesis (HMEC-1). This suggests that heat treated luteolin has a lower anti-tumor potential than native luteolin. Graphical abstract ᅟ.

Celecoxib in breast cancer prevention and therapy

Breast cancer has a high incidence worldwide. The results of substantial studis reveal that inflammation plays an important role in the initiation, development, and aggressiveness of many malignancies. The use of celecoxib, a novel NSAID, is repetitively associated with the reduced risk of the occurrence and progression of a number of types of cancer, particularly breast cancer. This observation is also substantiated by various meta-analyses. Clinical trials have been implemented on integration treatment of celecoxib and shown encouraging results. Celecoxib could be treated as a potential candidate for antitumor agent. There are, nonetheless, some unaddressed questions concerning the precise mechanism underlying the anticancer effect of celecoxib as well as its activity against different types of cancer. In this review, we discuss different mechanisms of anticancer effect of celecoxib as well as preclinical/clinical results signifying this beneficial effect.

Mechanism of metastasis suppression by luteolin in breast cancer

Metastatic breast cancer is typically an extremely aggressive cancer with poor prognosis. Metastasis requires the orchestration of homeostatic factors and cellular programs, many of which are potential therapeutic targets. Luteolin (2-[3,4-dihydroxyphenyl]-5,7-dihydroxy-4-chromenone), is a naturally occurring flavonoid found in fruits and vegetables that exhibits many anticancer properties. Luteolin obstructs metastasis through both direct and indirect mechanisms. For instance, luteolin may suppress breast cancer invasion by acting as an antiangiogenic therapeutic inhibiting VEGF production and its receptor’s activity. Furthermore, luteolin decreases epithelial–mesenchymal transition markers and metastatic proclivity. Luteolin also acts as an antiproliferative by suppressing receptor tyrosine-kinase activity and apoptosis, both of which could prevent incipient colonization of breast cancer. Many of these antimetastatic characteristics accredited to luteolin are likely functionally related. For instance, the PI3K/Akt pathway, which is impeded by luteolin, has several downstream programs involved in increased proliferation, survival, and metastatic potential in breast cancer. In this review, luteolin’s ability to ameliorate breast cancer is summarized. The paper also offers insight into the molecular mechanisms by which luteolin may suppress breast cancer metastasis.

Curcumol potentiates celecoxib-induced growth inhibition and apoptosis in human non-small cell lung cancer

Combinatorial therapies that target multiple signaling pathways may provide improved therapeutic responses over monotherapies. Celecoxib and curcumol are two highly hydrophobic drugs which show bioavailability problems due to their poor aqueous solubility. In the present study, we evaluated the effects of celecoxib and curcumol alone and in combination on cell proliferation, invasion, migration, cell cycle and apoptosis induction in non-small cell lung cancer (NSCLC) cells using in vitro and in vivo experiments. Our data showed that the sensitivity of a combined therapy using low concentration of celecoxib and curcumol was higher than that of celecoxib or curcumol alone. Suppression of NF-κB transcriptional activity, activation of caspase-9/caspase-3, cell cycle G1 arrest, and inhibition of survival MAPK and PI3K/AKT signaling pathway contributed to the synergistic effects of this combination therapy for induction of apoptosis. Additionally, either celecoxib alone or in combination with curcumol inhibited NSCLC cell migration and invasion by suppressing FAK and matrix metalloproteinase-9 activities. Furthermore, the combined treatment reduced tumor volume and weight in xenograft mouse model, and significantly decreased tumor metastasis nodules in lung tissues by tail vein injection. Our results confirm and provide mechanistic insights into the prominent anti-proliferative activities of celecoxib and/or curcumol on NSCLC cells, which provide a rationale for further detailed preclinical and potentially clinical studies of this combination for the therapy of lung cancer.

Facile synthesis of mPEG-luteolin-capped silver nanoparticles with antimicrobial activity and cytotoxicity to neuroblastoma SK-N-SH cells

We firstly report a facile route for the green synthesis of mPEG-luteolin-capped silver nanoparticles (mPEG-luteolin-AgNPs) using mPEG-luteolin as both the reducer and stabilizer. The reaction was carried out in a stirred aqueous solution at 50°C without additional poisonous reagents. The prepared mPEG-luteolin-AgNPs was characterized by scanning electron microscope (SEM), transmission electron microscopy (TEM), fourier transform infrared spectroscopy (FTIR), X-ray powder diffraction (XRD), zeta potential and UV-vis (UV-vis) spectrum, respectively. The proportions of mPEG-luteolin capped silver nanoparticles is about 89.9%, and the content of silver is 6.65%. The mPEG-luteolin-AgNPs was evaluated the antimicrobial effects on Staphlococcus aureus, Extended spectrum β-Lactamases Staphlococcus aureus, Escherichia Coli and Extended spectrum β-Lactamases Escherichia Coli using drilling hole method. The results showed that both gram-positive and gram-negative bacteria were killed by the mPEG-luteolin-AgNPs at low concentration. Meanwhile, the cell viability assay demonstrated that mPEG-luteolin-AgNPs had toxic effects on human neuroblastoma SK-N-SH cells.

Preparation and Characterization of Copolymer Micelles for the Solubilization and In Vitro Release of Luteolin and Luteoloside

Luteolin (LUT) and luteoloside (LUS) belong to flavonoids with high anticancer potential and were loaded into biodegradable diblock copolymer micelles of methoxy polyethylene glycol-polycaprolactone (mPEG_5K-PCL_10K), methoxy polyethylene glycol-polylactide-co-glycolide (mPEG_5K-PLGA_10K), and methoxy polyethylene glycol-polylactide (mPEG_5K-PDLLA_10K) by a self-assembly method, creating water-soluble LUT and LUS copolymer micelles, respectively. The solubilization formulations of the copolymer micelles were optimized with response surface methodology (RSM). The obtained drug micelles are torispherical under transmission electron microscope (TEM) with an average diameter of about 70 nm. The mPEG_5K-PLGA_10K exhibited higher loading capacity for LUS which was 4.33%, and LUT- (or LUS)-loaded mPEG_5K-PCL_10K exhibited a better stability and encapsulation efficiency which was 65.1 and 55.8%, respectively. The in vitro drug release study showed above 47% of LUT was released from micelles at pH 7.4 PBS; however, no more than 35% of LUT was released at pH 6.4 PBS within 24 h. Meanwhile, no more than 30% of LUS was released from micelles whether at pH 6.4 or 7.4 PBS solution within 24 h.

Improving In Vivo Efficacy of Bioactive Molecules: An Overview of Potentially Antitumor Phytochemicals and Currently Available Lipid-Based Delivery Systems

Cancer is among the leading causes of morbidity and mortality worldwide. Many of the chemotherapeutic agents used in cancer treatment exhibit cell toxicity and display teratogenic effect on nontumor cells. Therefore, the search for alternative compounds which are effective against tumor cells but reduce toxicity against nontumor ones is of great importance in the progress or development of cancer treatments. In this sense, scientific knowledge about relevant aspects of nutrition intimately involved in the development and progression of cancer progresses rapidly. Phytochemicals, considered as bioactive ingredients present in plant products, have shown promising effects as potential therapeutic/preventive agents on cancer in several in vitro and in vivo assays. However, despite their bioactive properties, phytochemicals are still not commonly used in clinical practice due to several reasons, mainly attributed to their poor bioavailability. In this sense, new formulation strategies are proposed as carriers to improve their bioefficacy, highlighting the use of lipid-based delivery systems. Here, we review the potential antitumoral activity of the bioactive compounds derived from plants and the current studies carried out in animal and human models. Furthermore, their association with lipids as a formulation strategy to enhance their efficacy in vivo is also reported. The development of high effective bioactive supplements for cancer treatment based on the improvement of their bioavailability goes through this association.

Hydrogels generated by low-molecular-weight PEGylated luteolin and α-cyclodextrin through self-assembly for 5-fluorouracil delivery

Hydrophobic luteolin (LUT) was conjugated to the oligomeric chain of methoxypoly(ethylene glycol) (mPEG) to form novel amphiphilic mPEG₁₉₀₀–LUT conjugates.

Mast cells in meningiomas and brain inflammation

Background

Research focus in neuro-oncology has shifted in the last decades towards the exploration of tumor infiltration by a variety of immune cells and their products. T cells, macrophages, B cells, and mast cells (MCs) have been identified.

Methods

A systematic review of the literature was conducted by searching PubMed, EMBASE, Google Scholar, and Turning Research into Practice (TRIP) for the presence of MCs in meningiomas using the terms meningioma, inflammation and mast cells.

Results

MCs have been detected in various tumors of the central nervous system (CNS), such as gliomas, including glioblastoma multiforme, hemangioblastomas, and meningiomas as well as metastatic brain tumors. MCs were present in as many as 90 % of all high-grade meningiomas mainly found in the perivascular areas of the tumor. A correlation between peritumoral edema and MCs was found.

Interpretation

Accumulation of MCs in meningiomas could contribute to the aggressiveness of tumors and to brain inflammation that may be involved in the pathogenesis of additional disorders.

Luteolin as an anti-inflammatory and neuroprotective agent: A brief review

According to the World Health Organization, two billion people will be aged 60 years or older by 2050. Aging is a major risk factor for a number of neurodegenerative disorders. These age-related disorders currently represent one of the most important and challenging health problems worldwide. Therefore, much attention has been directed towards the design and development of neuroprotective agents derived from natural sources. These phytochemicals have demonstrated high efficacy and low adverse effects in multiple in vitro and in vivo studies. Among these phytochemicals, dietary flavonoids are an important and common chemical class of bioactive products, found in several fruits and vegetables. Luteolin is an important flavone, which is found in several plant products, including broccoli, pepper, thyme, and celery. Numerous studies have shown that luteolin possesses beneficial neuroprotective effects both in vitro and in vivo. Despite this, an overview of the neuroprotective effects of luteolin has not yet been accomplished. Therefore, the aim of this paper is to provide a review of the available literature regarding the neuroprotective effects of luteolin and its molecular mechanisms of action. Herein, we also review the available literature regarding the chemistry of luteolin, its herbal sources, and bioavailability as a pharmacological agent for the treatment and management of age-related neurodegenerative disorders.

Synergistic effect between celecoxib and luteolin is dependent on estrogen receptor in human breast cancer cells

The anti-cancer effects of celecoxib and luteolin are well known. Although our previous study demonstrated that the combination of celecoxib and luteolin synergistically inhibits breast tumor growth compared with each of the treatments alone, we did not uncover the molecular mechanisms of these effects. The aims of our present study were to compare the effects of a celecoxib and luteolin combination treatment in four different human breast cell lines and to determine the mechanisms of action in vitro and in vivo. The synergistic effects of a celecoxib and luteolin combination treatment yielded significantly greater cell growth inhibition in all four breast cancer cell lines compared with the single agents alone. In particular, combined celecoxib and luteolin treatment significantly decreased the growth of MDA-MB-231 cancer cells in vivo compared with either agent alone. The celecoxib and luteolin combination treatment induced synergistic effects via Akt inactivation and extracellular signal-regulated kinase (ERK) signaling inhibition in MCF-7 and MCF7/HER18 cells and via Akt inactivation and ERK signaling activation in MDA-MB-231 and SkBr3 cells. These results demonstrate the synergistic anti-tumor effect of the celecoxib and luteolin combination treatment in different four breast cancer cell lines, thus introducing the possibility of this combination as a new treatment modality.

Poly-γ-glutamic acid induces apoptosis via reduction of COX-2 expression in TPA-induced HT-29 human colorectal cancer cells

Poly-γ-glutamic acid (PGA) is one of the bioactive compounds found in cheonggukjang, a fast-fermented soybean paste widely utilized in Korean cooking. PGA is reported to have a number of beneficial health effects, and interestingly, it has been identified as a possible anti-cancer compound through its ability to promote apoptosis in cancer cells, although the precise molecular mechanisms remain unclear. Our findings demonstrate that PGA inhibits the pro-proliferative functions of the phorbol ester 12-O-tetradecanoylphorbol-13-acetate (TPA), a known chemical carcinogen in HT-29 human colorectal cancer cells. This inhibition was accompanied by hallmark apoptotic phenotypes, including DNA fragmentation and the cleavage of poly (ADP-ribose) polymerase (PARP) and caspase 3. In addition, PGA treatment reduced the expression of genes known to be overexpressed in colorectal cancer cells, including cyclooxygenase 2 (COX-2) and inducible nitric oxide synthase (iNOS). Lastly, PGA promoted activation of 5' adenosine monophosphate-activated protein (AMPK) in HT-29 cells. Taken together, our results suggest that PGA treatment enhances apoptosis in colorectal cancer cells, in part by modulating the activity of the COX-2 and AMPK signaling pathways. These anti-cancer functions of PGA make it a promising compound for future study.

Luteolin and Gemcitabine Protect Against Pancreatic Cancer in an Orthotopic Mouse Model

OBJECTIVE

This study aimed to evaluate the ability of luteolin (Lut), gemcitabine (Gem), and their combination (Lut + Gem) to prevent the growth of pancreatic tumors in vivo.

METHODS

The antitumor effect of intraperitoneally administered Lut, Gem, and Lut + Gem was evaluated using an orthotopic mouse model for 6 weeks. Tumor growth after injection of human pancreatic cancer cells was assessed by measuring pancreatic tumor mass. The mechanism of action of antitumor effect was assessed by immunohistochemistry and Western blot procedures.

RESULTS

Luteolin + Gem significantly lowered (P = 0.048) the pancreatic tumor mass compared with control. Luteolin, Gem, and Lut + Gem significantly reduced the proliferating cell nuclear antigen expression (25%, 37%, and 37%, respectively). Luteolin + Gem treatment led to a significant reduction in the expressions of K-ras (46%, P = 0.0006), GSK-3β (34%, P = 0.014), P(Tyr216)GSK-3β (16%, P = 0.033), P(Ser311)NF-κB p65 (27%, P = 0.036), and bcl-2/bax ratio (68%, P = 0.006) while significantly increasing the expressions of cytochrome c (44%, P = 0.035) and caspase 3 (417%, P = 0.003).

CONCLUSIONS

Luteolin + Gem promoted apoptotic cell death in pancreatic tumor cells in vivo through inhibition of the K-ras/GSK-3β/NF-κB signaling pathway, leading to a reduction in the Bcl-2/Bax ratio, release of cytochrome c, and activation of caspase 3.

Differential metabolomic analysis of the potential antiproliferative mechanism of olive leaf extract on the JIMT-1 breast cancer cell line

A new differential metabolomic approach has been developed to identify the phenolic cellular metabolites derived from breast cancer cells treated with a supercritical fluid extracted (SFE) olive leaf extract. The SFE extract was previously shown to have significant antiproliferative activity relative to several other olive leaf extracts examined in the same model. Upon SFE extract incubation of JIMT-1 human breast cancer cells, major metabolites were identified by using HPLC coupled to electrospray ionization quadrupole-time-of-flight mass spectrometry (ESI-Q-TOF-MS). After treatment, diosmetin was the most abundant intracellular metabolite, and it was accompanied by minor quantities of apigenin and luteolin. To identify the putative antiproliferative mechanism, the major metabolites and the complete extract were assayed for cell cycle, MAPK and PI3K proliferation pathways modulation. Incubation with only luteolin showed a significant effect in cell survival. Luteolin induced apoptosis, whereas the whole olive leaf extract incubation led to a significant cell cycle arrest at the G1 phase. The antiproliferative activity of both pure luteolin and olive leaf extract was mediated by the inactivation of the MAPK-proliferation pathway at the extracellular signal-related kinase (ERK1/2). However, the flavone concentration of the olive leaf extract did not fully explain the strong antiproliferative activity of the extract. Therefore, the effects of other compounds in the extract, probably at the membrane level, must be considered. The potential synergistic effects of the extract also deserve further attention. Our differential metabolomics approach identified the putative intracellular metabolites from a botanical extract that have antiproliferative effects, and this metabolomics approach can be expanded to other herbal extracts or pharmacological complex mixtures.

Combined cetuximab and celecoxib treatment exhibits a synergistic anticancer effect on human oral squamous cell carcinoma in vitro and in vivo

The aim of the present study was to evaluate the potency of epidermal growth factor receptor (EGFR) pathway inhibition achieved by combining cetuximab (CET), an anti-EGFR monoclonal antibody, and celecoxib (CXB), a cyclooxygenase-2 (COX-2) inhibitor, in oral squamous cell carcinoma (OSCC) in vitro and in vivo. The OSCC cell line, HSC3, was treated with CET (0-400 µg/ml), CXB (0-40 µM), or a combination of both at a range of concentrations. Cell proliferation, apoptosis, migration and invasion were determined to assess the anticancer effects in vitro. The in vivo effects of CET and CXB on tumor cell growth were examined using an OSCC xenograft nude mouse model. In addition, downstream protein expression levels of EGFR, p-EGFR, PI3K, p-PI3K, AKT and p-Akt were evaluated by western blot analysis. It was found that the combination of low concentrations of CET and CXB significantly suppressed the proliferation, migration and invasion of the HSC3 tumor cells and decreased PEG2 production and VEGF expression in vitro, and inhibited tumor growth in vivo compared to the action of either agent alone. The results also showed that this combination significantly induced apoptosis and increased caspase-3 and caspase-8 activity compared to the action of either agent alone (P<0.01). Furthermore, the combination treatment significantly reduced the expression of p-EGFR, p-PI3K and p-Akt in the HSC3 cell line, which may contribute to the inhibition of tumor growth. Taken together, our findings revealed that the additive combination of CET and CXB is a potential drug candidate for the treatment of OSCC.