In vitro evaluation of the anticancer effect of lactoferrin and tea polyphenol combination on oral carcinoma cells

Insights into Nimbolide molecular crosstalk and its anticancer properties

Nimbolide, one of the main ingredients constituent of Azadirachta indica (neem) leaf extract, has garnered attention for its potential as an anticancer agent. Its efficacy against various cancers and chemopreventive action has been demonstrated through numerous in vivo and in vitro studies. This updated review aims to comprehensively explore the chemopreventive and anticancer properties of nimbolide, emphasizing its molecular mechanisms of action and potential therapeutic applications in oncology. The review synthesizes evidence from various studies that examine nimbolide's roles in apoptosis induction, anti-proliferation, cell death, metastasis inhibition, angiogenesis suppression, and modulation of carcinogen-metabolizing enzymes. Nimbolide exhibits multifaceted anticancer activities, including the modulation of multiple cell signaling pathways related to inflammation, invasion, survival, growth, metastasis, and angiogenesis. However, its pharmacological development is still in the early stages, mainly due to limited pharmacokinetic and comprehensive long-term toxicological studies. Nimbolide shows promising anticancer and chemopreventive properties, but there is need for systematic preclinical pharmacokinetic and toxicological research. Such studies are essential for establishing safe dosage ranges for first-in-human clinical trials and further advancing nimbolide's development as a therapeutic agent against various cancers. The review highlights the potential of nimbolide in cancer treatment and underscores the importance of rigorous preclinical evaluation to realize its full therapeutic potential.

Coleus vettiveroides ethanolic root extract induces cytotoxicity by intrinsic apoptosis in HepG2 cells

Hepatocellular carcinoma (HCC) contributes to more than 80% of all primary cancers globally and ranks fourth in cancer-related deaths, due to the lack of an effective, definite therapeutic drug. Coleus vettiveroides (CV) has been used in Indian traditional medicine to treat diabetes, liver ailments, skin diseases, leukoderma, and leprosy. This study investigates the anticancer effect of CV ethanolic root extract in HepG2 cells. HepG2 cells were treated with CV extract, and its cytotoxicity was analyzed by MTT assay. AO/EB staining, propidium iodide staining, DCFH-DA assay, phalloidine staining, flow cytometry, and qPCR studies were performed for ROS expression, apoptosis and cell cycle analysis. The phytochemical analysis confirmed the presence of quercetin and galangin in CV root extract. The results showed that CV inhibited the proliferation of HepG2 cells, with altered cellular and nuclear morphology. CV was also found to increase intracellular ROS levels and oxidative stress markers in HepG2 cells. CV significantly altered the actin microfilament distribution in HepG2 cells and caused cell cycle arrest at the sub G0 -G1 phase. CV also induced mitochondria-mediated apoptosis, as evidenced by increased expression of p53, Bax, cytochrome C, Apaf-1, PARP, caspase-3 and caspase-9, and downregulated Bcl-2 expression. Therefore, CV exerts its anticancer effect by inducing mitochondrial dysfunction, oxidative stress, cytoskeletal disorganization, cell cycle arrest, and mitochondria-mediated apoptosis, and it could be a potent therapeutic option for HCC.

Can a cup a day keep cancer away? A systematic review exploring the potential of coffee constituents in preventing oral squamous cell carcinoma

BACKGROUND

Coffee is one of the most consumed beverages in the world. Containing an abundance of bioactive molecules including polyphenols and flavonoids, the constituents of this beverage may exert antiproliferative, antioxidant and anti-inflammatory effects.

METHODS

We conducted a systematic review to summarise the available evidence on the anticancer effects of coffee constituents and their potential therapeutic use for oral squamous cell carcinoma (OSCC). Studies were identified through a comprehensive search of OVID MEDLINE, OVID EMBASE and Web of Science, including articles from any year up to 15 May 2023.

RESULTS

Of the 60 reviewed papers, 45 were in vitro, 1 was in silico and 8 were in vivo exclusively. The remaining studies combined elements of more than one study type. A total of 55 studies demonstrated anti-proliferative effects, whilst 12 studies also investigated migration and invasion of neoplastic cells. The constituents studied most frequently were quercetin and epigallocatechin gallate (EGCG), demonstrating various cytotoxic effects whilst also influencing apoptotic mechanisms in cancer cell lines. Dose-dependent responses were consistently found amongst the studied constituents.

CONCLUSION

Whilst there was heterogeneity of study models and methods, consistent use of specific models such as SCC25 for in vitro studies and golden hamsters for in vivo studies enabled relative comparability. The constituents of coffee have gained significant interest over the last 30 years, particularly in the last decade, and present an area of interest with significant public health implications. Currently, there is a paucity of literature on utilization of active coffee constituents for the therapeutic treatment of oral cancers.

Enhancing Osteoblastic Cell Cultures with Gelatin Methacryloyl, Bovine Lactoferrin, and Bioactive Mesoporous Glass Scaffolds Loaded with Distinct Parsley Extracts

The increasing interest in innovative solutions for addressing bone defects has driven research into the use of Bioactive Mesoporous Glasses (MBGs). These materials, distinguished by their well-ordered mesoporous structure, possess the capability to accommodate plant extracts with well-established osteogenic properties, including bovine lactoferrin (bLF), as part of their 3D scaffold composition. This harmonizes seamlessly with the ongoing advancements in the field of biomedicine. In this study, we fabricated 3D scaffolds utilizing MBGs loaded with extracts from parsley leaves (PL) and embryogenic cultures (EC), rich in bioactive compounds such as apigenin and kaempferol, which hold potential benefits for bone metabolism. Gelatin Methacryloyl (GelMa) served as the polymer, and bLF was included in the formulation. Cytocompatibility, Runx2 gene expression, ALP enzyme activity, and biomineralization were assessed in preosteoblastic MC3T3-E1 cell cultures. MBGs effectively integrated PL and EC extracts with loadings between 22.6 ± 0.1 and 43.6 ± 0.3 µM for PL and 26.3 ± 0.3 and 46.8 ± 0.4 µM for EC, ensuring cell viability through a release percentage between 28.3% and 59.9%. The incorporation of bLF in the 3D scaffold formulation showed significant differences compared to the control in all assays, even at concentrations below 0.2 µM. Combinations, especially PL + bLF at 0.19 µM, demonstrated additive potential, with superior biomineralization compared to EC. In summary, this study highlights the effectiveness of MBGs in incorporating PL and EC extracts, along with bLF, into 3D scaffolds. The results underscore cytocompatibility, osteogenic activity, and biomineralization, offering exciting potential for future in vivo applications.

Polyphenols in Oral Health: Homeostasis Maintenance, Disease Prevention, and Therapeutic Applications

Polyphenols, a class of bioactive compounds with phenolic structures, are abundant in human diets. They have gained attention in biomedical fields due to their beneficial properties, including antioxidant, antibacterial, and anti-inflammatory activities. Therefore, polyphenols can prevent multiple chronic or infectious diseases and may help in the prevention of oral diseases. Oral health is crucial to our well-being, and maintaining a healthy oral microbiome is essential for preventing various dental and systemic diseases. However, the mechanisms by which polyphenols modulate the oral microbiota and contribute to oral health are still not fully understood, and the application of polyphenol products lies in different stages. This review provides a comprehensive overview of the advancements in understanding polyphenols' effects on oral health: dental caries, periodontal diseases, halitosis, and oral cancer. The mechanisms underlying the preventive and therapeutic effects of polyphenols derived from dietary sources are discussed, and new findings from animal models and clinical trials are included, highlighting the latest achievements. Given the great application potential of these natural compounds, novel approaches to dietary interventions and oral disease treatments may emerge. Moreover, investigating polyphenols combined with different materials presents promising opportunities for developing innovative therapeutic strategies in the treatment of oral diseases.

Low-level Cu-fortification of bovine lactoferrin: Focus on its effect on in vitro anti-inflammatory activity in LPS-stimulated macrophages

Bovine lactoferrin (LF) per 1 g was reacted with 0.16, 0.32, and 0.64 mg CuCl₂ to reach 10%, 20%, and 40% copper-saturation, respectively, aiming to assess their anti-inflammatory activities to lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages. The macrophages treated with CuCl₂ at 0.051 μg/mL dose did not have obvious change in cell viability, lactate dehydrogenase (LDH) release, and intracellular reactive oxygen species (ROS) production. However, LF and Cu-fortified LF products (10-80 μg/mL doses) mostly showed inhibitory effects on the stimulated macrophages dose-dependently. Moreover, Cu-fortified LF products of lower Cu-fortifying levels at lower doses exerted weaker inhibition on the stimulated macrophages than LF, leading to higher cell viability but decreased LDH release. Meanwhile, LF and Cu-fortified LF products at 10 and 20 μg/mL doses showed different activities to the stimulated cells, via partly decreasing or increasing the production of inflammatory mediators namely prostaglandin E₂ (PGE₂), nitric oxide, tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), IL-1β, and ROS production, depending on the used Cu-fortifying and dose levels. Compared with LF, Cu-fortified LF product (Cu-fortifying level of 0.16 mg/g LF) at 10 μg/mL dose showed enhanced inhibition on the production of PGE₂, ROS, IL-1β, and TNF-α, evidencing increased anti-inflammatory activity. However, the inhibition of Cu-fortified LF product (Cu-fortifying level of 0.32 mg/g LF) at 20 μg/mL dose on the production of these inflammatory mediators was mostly reduced. It is thus proposed that both Cu-fortifying and dose levels could affect LF's anti-inflammatory activity in LPS-stimulated macrophages, while the Cu-fortifying level of LF could govern activity change.

Inhibition of Cell Proliferation and Cell Viability by Sinecatechins in Cutaneous SCC Cells Is Related to an Imbalance of ROS and Loss of Mitochondrial Membrane Potential

The term sinecatechins designates an extract containing a high percentage of catechins obtained from green tea, which is commercially registered as Veregen or Polyphenon E (PE) and may be considered for treatment of cutaneous squamous cell carcinoma (cSCC) and actinic keratosis (AK). As shown here, treatment of four cSCC cell lines with 200 µg/mL of PE resulted in strong, dose-dependent decrease in cell proliferation (20–30%) as well as strongly decreased cell viability (4–21% of controls, 48 h). Effects correlated with loss of mitochondrial membrane potential, whereas early apoptosis was less pronounced. At the protein level, some activation of caspase-3 and enhanced expression of the CDK inhibitor p21 were found. Loss of MMP and induced cell death were, however, largely independent of caspases and of the proapoptotic Bcl-2 proteins Bax and Bak, suggesting that sinecatechins induce also non-apoptotic, alternative cell death pathways, in addition to apoptosis. Reactive oxygen species (ROS) were downregulated in response to PE at 4 h, followed by an increase at 24 h. The contributory role of initially reduced ROS was supported by the antioxidant N-acetyl cysteine, which in combination with PE further enhanced the negative effects on cell viability. Thus, sinecatechins inhibited cell proliferation and viability of cSCC cells, which could suggest the use of PE for AK treatment. The mechanisms appear as linked to an imbalance of ROS levels.

Baicalein inhibits cell proliferation and enhances apoptosis in human A549 cells and benzo(a)pyrene-induced pulmonary carcinogenesis in mice

Our current study is done to explore the possible mechanisms to elaborate on the growth inhibitory effect of baicalein (BE) in human lung carcinoma. Initially, BE (25 and 50 µM) treatment for 24 h, suppressed the viability and inhibited population growth in A549 cells. BE upholds the production of reactive oxygen species (ROS) with concomitant replenishment of glutathione, catalase, and glutathione peroxidase activity. The expression level of nuclear factor erythroid 2-related factor 2 and heme oxygenase-1 markedly increased after BE treatment will intimidate A549 cells proliferation by the ROS-independent pathway via the antioxidant pathway. In vivo investigations were carried out on BE (12 mg/kg, oral) in benzo(a)pyrene (B(a)P; 50 mg/kg, oral) induced lung carcinogenesis in mice. BE induces caspase-dependent apoptosis by increasing the levels of cytosolic cytochrome c accompanied by upregulating the outflow of p53, Bax, and caspase-3 with a concomitant abatement in the outflow of Bcl-2 in both in vitro and in vivo. In the murine model, BE treatment hindered the countenance of proliferation-related proteins (argyrophilic nucleolar organizing regions and proliferating cell nuclear antigen). Additionally, appraisal of the cell nucleus by transmission electron microscopic assessment uncovered that BE treatment adequately counteracts B(a)P-induced lung cancer cell survival. During the transition of the G₀ /G₁ phase, BE is arrested in the cell cycle process. This might be the cause of a substantial increase in the appearance of p21^Cip1 with concomitant downregulating the expressions of CDK4, cyclin D, and cyclin E both in vitro and in vivo. Our results conclude that BE treatment induced apoptosis and repressed proliferation both in vitro and in vivo of human lung carcinoma.

Milk-Derived Proteins and Peptides in Head and Neck Carcinoma Treatment

Research investigating milk-derived proteins has brought to light the potential for their use as novel anticancer agents. This paper aims to systematically review studies examining the effectiveness of milk-derived proteins in the treatment of head and neck cancer. A systematic literature search of Medline, Evidence-Based Medicine, and Web of Science databases including papers published from all dates was completed. Inter-rater reliability was high during the title, abstract, and full-text screening phases. Inclusion criteria, exclusion criteria, and data extraction were based on the PICOS tool and research questions. Reporting followed the Preferred Reporting Items for Systematic Review and Meta-Analysis criteria. Eligible in vitro and in vivo studies (n = 8/658) evaluated lactoferrin, α-lactalbumin, and its complexes, such as HAMLET, BAMLET and lactalbumin-oleic acid complexes, as well as lactoperoxidase, whey, and casein. Their effectiveness in the treatment of head and neck cancer cells lines found that these compounds can inhibit tumour growth modulate cancer gene expression, and have cytotoxic effects on cancer cells. However, the exact mechanisms by which these effects are achieved are not well understood. Systematically designed, large, optimally controlled, collaborative studies, both in vitro and in vivo, will be required to gain a better understanding of their potential role in the treatment of head and neck cancer.

Therapeutic potential of camel milk exosomes against HepaRG cells with potent apoptotic, anti-inflammatory, and anti-angiogenesis effects for colostrum exosomes

This study aimed to evaluate and compare the therapeutic effect of camel milk exosomes derived from colostrum, early, mid, and late lactation periods on liver cancer HepaRG cells. These exosomes showed cytotoxicity on HepaRG while being safer on normal human liver THLE-2 cells. Among the four different isolated exosome groups, exosomes isolated from colostrum exhibited the highest apoptotic potential on HepaRG as indicated by highest DNA damage and upregulated expression of Bax and caspase3 expression, but with lowest Bcl2 expression. HepaRG-treated with colostrum-derived exosomes also exhibited the lowest expression of inflammation-related genes (TNFα, NFkB, TGFβ1, and Cox2) and the angiogenesis-related gene VEGF. Colostrum-derived exosomes had significantly higher expression of lactoferrin and kappa casein than other milk-derived exosomes. These results indicate that colostrum-derived exosomes have a more potent anti-cancer effect on HepaRG cells than exosomes derived from the early, mid, and lat lactation periods. This effect could be mediated through induction of apoptosis and inhibition of inflammation and angiogenesis. Therefore, these exosomes could be used as safe adjuvants/carriers to deliver chemotherapeutics and to potentiate their anticancer effect on liver cancer cells.

Effects of bioactive components of Pu-erh tea on gut microbiomes and health: A review

Pu-erh tea is a post-fermentation tea with unique flavor and multiple health benefits. Due to the various microorganisms involved in the post-fermentation process, Pu-erh tea contains highly complex components, which have rich interactions with the gut microbiomes (GMs). Because the structure and homeostasis of GMs are closely related to human wellness and the various diseases progress, the beneficial effects of Pu-erh tea on GMs have a great potential for application in health care. However, there is no systematic summary of the bioactive components of Pu-erh tea, and their effects on the GMs. Here, we review the current studies on the effects of Pu-erh tea and its bioactive components on the structure of GMs as well as on health improvement, and further discuss the relevant quality indicators. This "components - function - indicators" clue will hopefully stimulate the standardization of Pu-erh tea fermentation process and the development of its functional products.

Protein Nanoparticles for Enhanced Oral Delivery of Coenzyme-Q10: in Vitro and in Silico Studies

Coenzyme-Q10 (CoQ10) is a hydrophobic benzoquinone with antioxidant and anti-inflammatory properties. It is known to reduce oxidative stress in various health conditions. However, due to the low solubility, permeability, stability, and poor oral bioavailability, the oral dose of CoQ10 required for the desired therapeutic effect is very high. In the present study, CoQ10 is encapsulated into two milk derived proteins β-lactoglobulin and lactoferrin (BLG and LF) to produce self-assembled nanostructures of around 100-300 nm with high encapsulation efficiency (5-10% w/w). Both CoQ10-BLG and CoQ10-LF nanoparticles (NPs) significantly improved the aqueous solubility of CoQ10 60-fold and 300-fold, compared to CoQ10 alone, which hardly dissolves in water. Insight into the difference in solubility enhancement between BLG and LF was obtained using in silico modeling, which predicted that LF possesses multiple prospective CoQ10 binding sites, potentially enabling greater loading of CoQ10 on LF compared to BLG, which was predicted to be less capable of binding CoQ10. At pH 7.4, CoQ10-LF NPs showed a burst release between 30 min and 2 h then plateaued at 12 h with 30% of the total drug released over 48 h. However, pure CoQ10-BLG and pure CoQ10 had a significantly lower release rate with less than 15% and 8% cumulative release in 48 h, respectively. Most importantly, both BLG and LF NPs significantly improved CoQ10 permeability compared to the pre-dissolved drug across the Caco-2 monolayer with up to 2.5-fold apparent permeability enhancement for CoQ10-LF-further confirming the utility of this nanoencapsulation approach. Finally, in murine macrophage cells (J774A.1), CoQ10-LF NPs displayed significantly higher anti-ROS properties compared to CoQ10 (predissolved in DMSO) without affecting the cell viability. This study paves the way in improving oral bioavailability of poorly soluble drugs and nutraceuticals using milk-based self-assembled nanoparticles.

Wine Consumption and Oral Cavity Cancer: Friend or Foe, Two Faces of Janus

The health benefits of moderate wine consumption have been extensively studied during the last few decades. Some studies have demonstrated protective associations between moderate drinking and several diseases including oral cavity cancer (OCC). However, due to the various adverse effects related to ethanol content, the recommendation of moderate wine consumption has been controversial. The polyphenolic components of wine contribute to its beneficial effects with different biological pathways, including antioxidant, lipid regulating and anti-inflammatory effects. On the other hand, in the oral cavity, ethanol is oxidized to form acetaldehyde, a metabolite with genotoxic properties. This review is a critical compilation of both the beneficial and the detrimental effects of wine consumption on OCC.

Effects of flavonoids on tongue squamous cell carcinoma

Squamous cell carcinoma (SCC) of the tongue is associated with tobacco use, alcohol abuse, and human papillomavirus (HPV) infections. While clinical outcomes have recently improved for HPV-positive patients in general, 50% of patients suffering from tongue cancer die within 5 years of being diagnosed. Flavonoids are secondary plant metabolites with a wide range of biological activities including antioxidant, anti-inflammatory, and anticancer activities. Flavonoids have generated high interest as therapeutic agents owing to their low toxicity and their effects on a large variety of cancer cell types. In this literature review, we evaluate the actions of flavonoids on SCC of the tongue demonstrated in both in vivo and in vitro models.

Fabrication of surface-active antioxidant biopolymers by using a grafted scallop (Patinopecten yessoensis) gonad protein isolate–epigallocatechin gallate (EGCG) conjugate: improving the stability of tuna oil-loaded emulsions

A novel antioxidant system was developed to improve stability of tuna oil-loaded emulsions.

Studies on the Interaction between Three Small Flavonoid Molecules and Bovine Lactoferrin

The interaction between three flavonoids, i.e., Luteolin (LTL), Quercetin (QCT), and Naringenin (NGN) and bovine lactoferrin (BLF) at pH 7.4 was investigated by fluorescence quenching spectra, synchronous fluorescence spectra, and UV-visible absorption spectra. The results indicate the fluorescence of BLF quenched by Luteolin (LTL), Quercetin (QCT), and Naringenin (NGN) via static quenching. The main force between QCT and LTL with BLF was van der Waals interactions and hydrogen bonds. Electrostatic interactions played a major role in the binding process of interaction between NGN and BLF. Synchronous fluorescence was used to study the conformational changes of BLF. The values of binding constant (Ka) and number of binding sites (n) at different temperatures (300K, 305K, 310K) were also calculated, respectively. The results of corresponding thermodynamic parameters as well as binding distance between BLF and LTL, QCT, or GNG were obtained. These results implied that Luteolin (LTL), Quercetin (QCT), and Naringenin (NGN) could provide important guides for compound quantity (e.g., medicine dosage) and the design of new compounds (or drugs).

Independent and joint effects of tea and milk consumption on oral cancer among non-smokers and non-drinkers: a case-control study in China

This study aims to evaluate the independent and joint effects of tea and milk consumption on oral cancer risk among non-smokers and non-drinkers (NS/ND). A hospital-based case-control study was performed in Fujian, China. 421 cases and frequency-matched 1398 controls were included without tobacco smoking and alcohol drinking habits. Unconditional logistic regression model was used to assess the relationship of tea and milk consumption with oral cancer risk. Tea and milk consumption were significantly associated with decreased risk of oral cancer, the adjusted odds ratios (aORs) were 0.73 (95% CI: 0.54-0.97) and 0.69 (95% CI: 0.55-0.88), respectively. According to subgroup analysis, the inverse associations between tea consumption and oral cancer risk were only observed among the elders (>60 years) and urban residents. While the protect effect of milk drinking was more obvious in males, normal body mass index population (18.5–23.9), urban residents and those age ≤ 60 years. Additionally, a significantly multiplicative interaction between tea and milk consumption was observed for oral cancer risk (P = 0.001). The present study is the first to simultaneously assess the association of tea consumption and milk drinking with oral cancer risk. The results suggest that tea and milk consumption are independent protective factors for oral cancer among NS/ND, with a joint effect between them.

Acacia catechu Ethanolic Seed Extract Triggers Apoptosis of SCC-25 Cells

Background:

Acacia catechu Willd (Fabaceae), commonly known as catechu, cachou, and black cutch, has been studied for its hepatoprotective, antipyretic, antidiarrheal, hypoglycemic, anti-inflammatory, immunomodulatory, antinociceptive, antimicrobial, free radical scavenging, and antioxidant activities.

Objective:

We evaluated the cytotoxic activity of ethanol extract of A. catechu seed (ACS) against SCC-25 human oral squamous carcinoma cell line.

Methods:

Cytotoxic effect of ACS extract was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, using concentrations of 0.1–1000 μg/mL for 24 h. A. catechu ethanol seed extract was treated SCC-25 cells with 25 and 50 μg/mL. At the end of treatment period, apoptotic marker gene expressions such as caspase 8, 9, Bcl-2, Bax, and cytochrome c were evaluated by semiquantitative reverse transcription-polymerase chain reaction. Morphological changes of ACS treated SCC-25 cells was evaluated by acridine orange/ethidium bromide (AO/EB) dual staining. Nuclear morphology and DNA fragmentation was evaluated by propidium iodide (PI) staining.

Results:

A. catechu ethanol seed extract treatment caused cytotoxicity in SCC-25 cells with an IC₅₀ value of 100 μg/mL. Apoptotic markers caspases 8 and 9, cytochrome c, Bax gene expressions were significantly increased upon ACS extract treatment indicate the apoptosis induction in SCC-25 cells. This treatment also caused significant downregulation of Bcl-2 gene expression. Staining with AO/EB and PI shows membrane blebbing, and nuclear membrane distortion further confirms the apoptosis induction by ACS treatment in SCC-25 cells.

Conclusion:

The ethanol seed extracts of A. catechu was found to be cytotoxic at lower concentrations and induced apoptosis in human oral squamous carcinoma SCC-25 cells.

SUMMARY

Acacia catechu ethanolic seed extract contains phytochemicals such as epicatechin, rutin, and quercetin

Acacia catechu seed (ACS) extract significantly (P < 0.001) inhibits the active proliferation of human oral squamous carcinoma (SCC-25) cells

ACS extract treatment to SCC-25 cells significantly modulated the gene expressions pertaining to apoptosis and propidium iodide and acridine orange/ethidium bromide staining also confirm the apoptosis induction

Antiproliferative and apoptosis inducing activities of ACS extract is correlated with phytochemical contents.

Abbreviations used: ACS: Acacia catechu seed extract; MTT: 3 (4,5 dimethylthiazol 2 yl) 2,5 diphenyltetrazolium bromide; DMSO: Dimethyl sulfoxide; AO/EO: Acridine orange/ethidium bromide; LC MS: Liquid chromatography mass spectrometry.

Acacia catechu ethanolic bark extract induces apoptosis in human oral squamous carcinoma cells

Oral cancer is in approximately 30% of all cancers in India. This study was conducted to evaluate the cytotoxic activity of ethanolic extract of Acacia catechu bark (ACB) against human squamous cell carcinoma cell line-25 (SCC-25). Cytotoxic effect of ACB extract was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium Bromide assay. A. catechu extract was treated SCC-25 cells with 25 and 50 μg/mL for 24 h. Apoptosis markers such as caspases-8 and 9, bcl-2, bax, and cytochrome c (Cyt-c) were done by RT-PCR. Morphological changes of ACB treated cells were evaluated using acridine orange/ethidium bromide (AO/EB) dual staining. Nuclear morphology and DNA fragmentation were evaluated using propidium iodide (PI) staining. Further, cell cycle analysis was performed using flow cytometry. A. catechu treatment caused cytotoxicity in SCC-25 cells with an IC₅₀ of 52.09 μg/mL. Apoptotic marker gene expressions were significantly increased on ACB treatment. Staining with AO/EB and PI shows membrane blebbing and nuclear membrane distortion, respectively, and it confirms the apoptosis induction in SCC-25 cells. These results suggest that ACB extract can be used as a modulating agent in oral squamous cell carcinoma.

Pro-apoptotic and anti-proliferative effects of corn silk extract on human colon cancer cell lines

Corn silk is an economically and nutritionally significant natural product as it represents a staple food for a large proportion of the world population. This study investigated the anticancer activity of corn silk extract in human colon cancer cells and human gastric cancer cells. Following treatment with corn silk extract, certain apoptosis-related events were observed, including inhibition of cell proliferation, loss of mitochondrial membrane potential (ΔΨm), release of Ca2+ and release of cytochrome c from the mitochondria into the cytosol. Our results revealed that corn silk extract inhibited the proliferation of cancer cells and increased the level of apoptosis in a concentration-dependent manner. Western blot analysis revealed that corn silk extract upregulated the levels of Bax, cytochrome c, caspase-3 and caspase-9, but downregulated the levels of B-cell lymphoma 2. These results suggest that corn silk extract may induce apoptosis through the mitochondria-mediated pathway.

Green tea and anticancer perspectives: updates from last decade

Green tea is the most widely consumed beverage besides water and has attained significant attention owing to health benefits against array of maladies, e.g., obesity, diabetes mellitus, cardiovascular disorders, and cancer insurgence. The major bioactive molecules are epigallocatechin-3-gallate, epicatechin, epicatechin-3-gallate, epigallocatechin, etc. The anticarcinogenic and antimutagenic activities of green tea were highlighted some years ago. Several cohort studies and controlled randomized trials suggested the inverse association of green tea consumption and cancer prevalence. Cell culture and animal studies depicted the mechanisms of green tea to control cancer insurgence, i.e., induction of apoptosis to control cell growth arrest, altered expression of cell-cycle regulatory proteins, activation of killer caspases, and suppression of nuclear factor kappa-B activation. It acts as carcinoma blocker by modulating the signal transduction pathways involved in cell proliferation, transformation, inflammation, and metastasis. However, results generated from some research interventions conducted in different groups like smokers and nonsmokers, etc. contradicted with aforementioned anticancer perspectives. In this review paper, anticancer perspectives of green tea and its components have been described. Recent findings and literature have been surfed and arguments are presented to clarify the ambiguities regarding anticancer perspectives of green tea and its component especially against colon, skin, lung, prostate, and breast cancer. The heading of discussion and future trends is limelight of the manuscript. The compiled manuscript provides new avenues for researchers to be explored in relation to green tea and its bioactive components.

Biodegradable Eri silk nanoparticles as a delivery vehicle for bovine lactoferrin against MDA-MB-231 and MCF-7 breast cancer cells

This study used the Eri silk nanoparticles (NPs) for delivering apo-bovine lactoferrin (Apo-bLf) (~2% iron saturated) and Fe-bLf (100% iron saturated) in MDA-MB-231 and MCF-7 breast cancer cell lines. Apo-bLf and Fe-bLf-loaded Eri silk NPs with sizes between 200 and 300 nm (±10 nm) showed a significant internalization within 4 hours in MDA-MB-231 cells when compared to MCF-7 cells. The ex vivo loop assay with chitosan-coated Fe-bLf-loaded silk NPs was able to substantiate its future use in oral administration and showed the maximum absorption within 24 hours by ileum. Both Apo-bLf and Fe-bLf induced increase in expression of low-density lipoprotein receptor-related protein 1 and lactoferrin receptor in epidermal growth factor (EGFR)-positive MDA-MB-231 cells, while transferrin receptor (TfR) and TfR2 in MCF-7 cells facilitated the receptor-mediated endocytosis of NPs. Controlled and sustained release of both bLf from silk NPs was shown to induce more cancer-specific cytotoxicity in MDA-MB-231 and MCF-7 cells compared to normal MCF-10A cells. Due to higher degree of internalization, the extent of cytotoxicity and apoptosis was significantly higher in MDA-MB-231 (EGFR+) cells when compared to MCF-7 (EGFR−) cells. The expression of a prominent anticancer target, survivin, was found to be downregulated at both gene and protein levels. Taken together, all the observations suggest the potential use of Eri silk NPs as a delivery vehicle for an anti-cancer milk protein, and indicate bLf for the treatment of breast cancer.

Structural characterization and functional evaluation of lactoferrin–polyphenol conjugates formed by free-radical graft copolymerization

Covalent modifications of lactoferrin with EGCG, chlorogenic acid and gallic acid were performed by adopting a free-radical grafting procedure in aqueous media and they affect both structural and functional properties of the protein.

Native and thermally modified protein-polyphenol coassemblies: lactoferrin-based nanoparticles and submicrometer particles as protective vehicles for (-)-epigallocatechin-3-gallate

The interactions between native, thermally modified lactoferrin (LF) and (-)-epigallocatechin-3-gallate (EGCG) at pH 3.5, 5.0, and 6.5 were investigated. Turbidity, particle size, and charge of LF-EGCG complexes were mainly dominated by pH value and secondary structure of protein. At pH 3.5 and 5.0, LF-EGCG complexes were nanoparticles which had high ζ-potential, small size, and soluble state. At pH 6.5, they were submicrometer particles which exhibited low ζ-potential, large size, and insoluble state. The infrared spectra of freeze-dried LF-EGCG complexes showed that they were different from LF and EGCG alone. Far-UV CD results indicated that heat denaturation might irreversibly alter the secondary structure of LF and EGCG induced a progressive increase in the proportion of α-helix structure at the cost of β-sheet and unordered coil structure of LF at pH 3.5, 5.0, and 6.5. EGCG exhibited a strong affinity for native LF but a weak affinity for thermally modified LF at pH 5.0 and 6.5. An inverse result was observed at pH 3.5. These results could have potential for the development of food formulations based on LF as a carrier of bioactive compounds.

MAPLE-based method to obtain biodegradable hybrid polymeric thin films with embedded antitumoral agents

In this work, antitumor compounds, lactoferrin [recombinant iron-free (Apo-rLf)], cisplatin (Cis) or their combination were embedded within a biodegradable polycaprolactone (PCL) polymer thin film, by a modified approach of a laser-based technique, matrix-assisted pulsed laser evaporation (MAPLE). The structural and morphological properties of the deposited hybrid films were analyzed by Fourier-transform infrared spectroscopy (FTIR) and atomic force microscopy (AFM). The in vitro effect on the cells' morphology and proliferation of murine melanoma B16-F10 cells was investigated and correlated with the films' surface chemistry and topography. Biological assays revealed decreased viability and proliferation, lower adherence, and morphological modifications in the case of melanoma cells cultured on both Apo-rLf and Cis thin films. The antitumor effect was enhanced by deposition of Apo-rLf with Cis within the same film. The unique capability of the new approach, based on MAPLE, to embed antitumor active factors within a biodegradable matrix for obtaining novel biodegradable hybrid platform with increased antitumor efficiency has been demonstrated.

Chemopreventive and therapeutic effects of nimbolide in cancer: the underlying mechanisms

Cancer chemoprevention is a strategy taken to block, reverse or retard the multistep process of carcinogenesis, including the blockage of its vital morphogenetic milestones viz. normal-preneoplasia-neoplasia-metastasis. Naturally occurring phytochemicals are becoming increasingly popular over synthetic drugs for several reasons, including safety, efficacy and easy availability. Nimbolide, a triterpene derived from the leaves and flowers of neem, is widely used in traditional medical practices for treating various human ailments. The neem limonoid exhibits multiple pharmacological effects among which its anticancer activity is the most promising. The preclinical and mechanistic studies carried over the decades have shown that nimbolide inhibits tumorigenesis and metastasis without any toxicity and unwanted side effects. Nimbolide exhibits anticancer activity through selective modulation of multiple cell signaling pathways linked to inflammation, survival, growth, invasion, angiogenesis and metastasis. The present review highlights the current knowledge on molecular targets that contribute to the observed anticancer activity of nimbolide related to (i) inhibition of carcinogenic activation and induction of antioxidant and carcinogen detoxification enzymes, (ii) induction of growth arrest and apoptosis; and (iii) suppression of proinflammatory signaling pathways related to cancer progression.

Apoptosis and autophagy induction as mechanism of cancer prevention by naturally occurring dietary agents

Nontoxic naturally occurring compounds, especially those from dietary sources, are receiving increasing consideration for prevention and treatment of diseases including cancer. There is a growing need for innovative anticancer therapies and therefore search for natural compounds with novel biological activities or antineoplastic potential is currently an important area in drug discovery. Support for this interest also comes from increasing concern over the efficacy and safety of many conventional therapies, especially those that run over a long course of time. Laboratory studies in different in vitro and in vivo systems have shown that many natural compounds possess the capacity to regulate response to oxidative stress and DNA damage, suppress angiogenesis, inhibit cell proliferation and induce autophagy and apoptosis. This review discusses the induction of apoptosis and autophagy as a mechanism of cancer prevention by some of the most studied naturally occurring dietary compounds.

Antiproliferative properties of methanolic extract of Nigella sativa against the MDA-MB-231 cancer cell line

Breast cancer is the most commonly diagnosed cancer in women in the world and is one of the leading causes of death due to cancer. Health benefits have been linked to additive and synergistic combinations of phytochemicals in fruits and vegetables. Nigella sativa has been shown to possess anti-carcinogenic activity, inhibiting growth of several cancer cell lines in vitro. However, the molecular mechanisms of the anti-cancer properties of Nigella sativa phytochemical extracts have not been completely understood. Our data showed that Nigella sativa extracts significantly inhibited human breast cancer MDA-MB-231 cell proliferation at doses of 2.5-5 μg/mL (P<0.05). Apoptotic induction in MDA-MB-231 cells was observed in a dose-dependent manner after exposure to Nigella sativa extracts for 48 h. Real time PCR and flow cytometry analyses suggested that Nigella sativa extracts possess the ability to suppress the proliferation of human breast cancer cells through induction of apoptosis.

Protection of dietary polyphenols against oral cancer

Oral cancer represents a health burden worldwide with approximate 275,000 new cases diagnosed annually. Its poor prognosis is due to local tumor invasion and frequent lymph node metastasis. Better understanding and development of novel treatments and chemo-preventive approaches for the preventive and therapeutic intervention of this type of cancer are necessary. Recent development of dietary polyphenols as cancer preventives and therapeutic agents is of great interest due to their antioxidant and anti-carcinogenic activities. Polyphenols may inhibit carcinogenesis in the stage of initiation, promotion, or progression. In particular, dietary polyphenols decrease incidence of carcinomas and exert protection against oral cancer by induction of cell death and inhibition of tumor growth, invasion, and metastasis. In this review, we discuss current progress of dietary polyphenols against oral cancers in vitro, in vivo, and at population levels.

Autophagy is induced by 3β-O-succinyl-lupeol (LD9-4) in A549 cells via up-regulation of Beclin 1 and down-regulation mTOR pathway

The purpose of this study is to investigate the antitumor activity of a new derivative of lupeol-3β-O-succinyl-lupeol (LD9-4) and the molecular mechanism underlying cell death in human non-small cell lung cancer A549 cells. The results revealed that LD9-4 inhibited A549 cell proliferation in a time- and dose-dependent manner, with an IC(50) value of 5.78 ± 0.48 μM after cells exposed to LD9-4 for 72 h. Markers indicative of apoptosis (cell cycle arrest, phosphatidylserine externalization and Hoechst33258 staining) were uniformly negative in LD9-4 exposed cells. Interestingly, transmission electron microscope, MDC staining and LC3 level determination all confirmed that autophagy was induced in LD9-4 treated A549 cells. Furthermore, we found that LD9-4-induced autophagy in A549 cells was associated with the increase of intracellular reactive oxygen species and the decrease of phosphorylated mTOR and p70S6K levels. In the meanwhile, both mRNA and protein levels of Beclin 1 were up-regulated in a time-dependent manner. Our data suggest that autophagy is induced by LD9-4 in A549 cells, and the accumulating reactive oxygen species, up-regulation of Beclin 1 and inhibition of the mTOR signaling pathway are involved in this process.

The chemopreventive properties and therapeutic modulation of green tea polyphenols in oral squamous cell carcinoma

Chemoprevention is a relatively novel and promising approach for controlling cancer that uses specific natural products or synthetic agents to suppress, reverse, or prevent premalignancy before transformation into invasive cancer. Oral cavity squamous cell carcinoma (OCSCC) represents a large, worldwide health burden with approximately 274,000 cases diagnosed annually worldwide. Smoking and alcohol consumption are major inducers of OCSCC. Recently, the human papilloma virus was also shown to potentially be an etiologic factor. Due to its easily identifiable risk factors and the presence of premalignant regions, oral cancer makes a good candidate for chemoprevention. Green tea is the most widely consumed beverage in the world, and it has received considerable attention because of its abundant, scientifically proven, beneficial effects on human health. In this review, we discuss the role of green tea in oral cancer chemoprevention with regard to the multiple molecular mechanisms proposed in various in vitro, in vivo, and clinical trials.

The role of nutraceutical proteins and peptides in apoptosis, angiogenesis, and metastasis of cancer cells

The process of carcinogenesis is complex and not easy to eliminate. It includes the initial occurrence of genetic alterations which can lead to the inactivation of tumor-suppressor genes and further accumulation of genetic alterations during tumor progression. Looking for food and food components with biological properties, collectively called nutraceuticals, that can hinder such alterations and prevent the inactivation of tumor-suppressor genes is a very promising area for cancer prevention. Proteins and peptides are one group of nutraceuticals that show potential results in preventing the different stages of cancer including initiation, promotion, and progression. In this review, we summarized current knowledge on the use of nutraceutical proteins and peptides in cancer prevention and treatment. We focused on the role of plant protease inhibitors, lactoferrin and lactoferricin, shark cartilage, plant lectins, and lunasin in the apoptosis, angiogenesis, and metastasis of cancer cells. Also included are studies on bioavailability and clinical trials conducted on these promising proteins and peptides.

The neem limonoids azadirachtin and nimbolide induce cell cycle arrest and mitochondria-mediated apoptosis in human cervical cancer (HeLa) cells

Limonoids from the neem tree (Azadirachta indica) have attracted considerable research attention in recent years owing to their potent antioxidant and anti-proliferative effects. The present study was designed to investigate the cellular and molecular mechanisms by which azadirachtin and nimbolide exert cytotoxic effects in the human cervical cancer (HeLa) cell line. Both azadirachtin and nimbolide significantly suppressed the viability of HeLa cells in a dose-dependent manner by inducing cell cycle arrest at G0/G1 phase accompanied by p53-dependent p21 accumulation and down-regulation of the cell cycle regulatory proteins cyclin B, cyclin D1 and PCNA. Characteristic changes in nuclear morphology, presence of a subdiploid peak and annexin-V staining pointed to apoptosis as the mode of cell death. Increased generation of reactive oxygen species with decline in the mitochondrial transmembrane potential and release of cytochrome c confirmed that the neem limonoids transduced the apoptotic signal via the mitochondrial pathway. Altered expression of the Bcl-2 family of proteins, inhibition of NF-kappaB activation and over-expression of caspases and survivin provide compelling evidence that azadirachtin and nimbolide induce a shift of balance toward a pro-apoptotic phenotype. Antioxidants such as azadirachtin and nimbolide that can simultaneously arrest the cell cycle and target multiple molecules involved in mitochondrial apoptosis offer immense potential as anti-cancer therapeutic drugs.

[6]-Gingerol induces reactive oxygen species regulated mitochondrial cell death pathway in human epidermoid carcinoma A431 cells

Since skin cancer incidence and prevalence is constantly rising up the charts despite all efforts, search for newer, better agents for protection and treatment is required. Ginger (Zingiber officinale Roscoe), a monocotyledonous herb, is widely used as a herbal medicine, given the presence of homologous phenolic ketones, of which [6]-gingerol is the major one. The quantity of [6]-gingerol in the fresh ginger rhizome was found to be 104-965 microg/g in common varieties of ginger available in Indian market. Herein, [6]-gingerol was assessed for its anti-apoptotic effects in human epidermoid carcinoma A431 cells. [6]-Gingerol treatment exhibited considerable cytotoxicity as indicated by growth inhibition of A431 cells mediated via generation of reactive oxygen species (ROS). Increase in ROS led to decrease in mitochondrial membrane potential (MMP) and subsequent induction of apoptosis. Results revealed that perturbations in mitochondrial membrane are associated with deregulation of Bax/Bcl-2 ratio at gene transcriptional level as well as protein level, where treatment with [6]-gingerol leads to up-regulation of Cytochrome-c and Apaf-1 subsequently culminating in triggering of Caspase cascade. These firmly suggest that [6]-gingerol can be effectively used for the treatment of skin cancer.