Silkworm Pupa Protein Hydrolysate Induces Mitochondria-Dependent Apoptosis and S Phase Cell Cycle Arrest in Human Gastric Cancer SGC-7901 Cells

Insects as a Prospective Source of Biologically Active Molecules and Pharmaceuticals-Biochemical Properties and Cell Toxicity of Tenebrio molitor and Zophobas morio Cell-Free Larval Hemolymph

Insects are of great interest as novel sources of alternative proteins and biologically active compounds, primarily anticancer agents. Protein-rich insect larval hemolymph is a prospective candidate for pharmaceutical and food industry-related research. In this study, selected biochemical properties and cell toxicity of larval hemolymph from two mealworm species, Tenebrio molitor and Zophobas morio, were analyzed. Total proteins and carbohydrates, antioxidant capacity, and the level of lipid peroxidation were determined. Human cancer (U-87) and normometabolic (MRC-5) cells were treated with different concentrations of larval hemolymph proteins, and the effects on cell viability were assayed 24, 48, and 72 h after treatments. Z. morio hemolymph was shown to be richer in total proteins, showing a higher antioxidant capacity and lipid peroxidation level than T. molitor hemolymph, which was richer in total carbohydrates. Cytotoxicity assays showed that T. molitor and Z. morio hemolymphs differently affect the viability of U-87 and MRC-5 cells in cell type-, dose-, and time-dependent manners. Hemolymph from both species was more cytotoxic to U-87 cells than to MRC-5 cells, which was particularly prominent after 48 h. Additionally, a more potent cytotoxic effect of Z. morio hemolymph was observed on both cell lines, likely due to its higher antioxidant capacity, compared to T. molitor hemolymph.

Revisiting edible insects as sources of therapeutics and drug delivery systems for cancer therapy

Cancer has been medicine's most formidable foe for long, and the rising incidence of the disease globally has made effective cancer therapy a significant challenge. Drug discovery is targeted at identifying efficacious compounds with minimal side effects and developments in nanotechnology and immunotherapy have shown promise in the fight against this complicated illness. Since ancient times, insects and insect-derived products have played a significant role in traditional medicine across several communities worldwide. The aim of this study was to inspect the traditional use of edible insects in various cultures and to explore their modern use in cancer therapy. Edible insects are sources of nutrients and a variety of beneficial substances with anticancer and immunomodulatory potential. Recently, insect derived bioactive-components have also been used as nanoparticles either in combination with chemotherapeutics or as a nano-cargo for the enhanced delivery of chemotherapeutic drugs due to their high biocompatibility, low bio-toxicity, and their antioxidant and anticancer effects. The crude extracts of different edible insects and their active components such as sericin, cecropin, solenopsin, melittin, antimicrobial peptides and fibroin produce anti-cancer and immunomodulatory effects by various mechanisms which have been discussed in this review.

Nutritional aspects and dietary benefits of "Silkworms": Current scenario and future outlook

In the current scenario, it is estimated that by 2050, there will be an additional 2.5 billion people and a 70% increase in food demand. Crop yields are not increasing fast enough to support global needs, and world agriculture is facing several serious challenges. Therefore, insects can be a nutritious alternative to meet the ever-increasing food demand in the present and future. The majority of insect consumption occurs in developing countries, with approximately 1,900 insect species consumed worldwide. Food and feed derived from them are of high quality, have a high feed conversion ratio and emit a low level of greenhouse gases. Among insects silkworms are beneficial to humans, not only because of their high nutritional value, but also because of their several pharmacological properties. Silkworm eggs, larvae, and pupae contains high amount of proteins, oils, minerals, vitamins, and several other beneficial components which are nutritious as well as have positive effect on human health. Studies have shown that silkworm pupae protect the liver, enhance immunity, inhibit apoptosis, inhibit cancer, inhibit tumor growth, inhibit microbial growth, regulate blood glucose and blood lipids, and lower blood pressure. This review paper summerized the nutritional value of different life stages of silkworm, nutritional comparison of silkworm with the major human foods, and the effects of silkworm consumption on human health, thus ittargets to generate interest toward in sericulture and improve human health by using silkworm as a nutritious food and attain sustainability in food and nutritional security.

Nutritional Composition, Health Benefits, and Application Value of Edible Insects: A Review

For thousands of years, edible insects have been used as food to alleviate hunger and improve malnutrition. Some insects have also been used as medicines because of their therapeutic properties. This is not only due to the high nutritional value of edible insects, but more importantly, the active substances from edible insects have a variety of biofunctional activities. In this paper, we described and summarized the nutritional composition of edible insects and discussed the biological functions of edible insects and their potential benefits for human health. A summary analysis of the findings for each active function confirms that edible insects have the potential to develop functional foods and medicines that are beneficial to humans. In addition, we analyzed the issues that need to be considered in the application of edible insects and the current status of edible insects in food and pharmaceutical applications. We concluded with a discussion of regulations related to edible insects and an outlook on future research and applications of edible insects. By analyzing the current state of research on edible insects, we aim to raise awareness of the use of edible insects to improve human health and thus promote their better use and development.

Effect of Silkworm Pupa Protein Hydrolysates on Proliferation of Gastric Cancer Cells In Vitro

The proliferation inhibition effects of the hydrolysates from silkworm pupa proteins on MGC-803 gastric cancer cells were investigated in this study. The specific morphological changes (cell membrane, cell nucleus and cytoskeleton) of cells were measured. In vitro, the proliferation of MGC-803 cells was inhibited by silkworm pupa protein hydrolysates (SPPHs) in a dose-dependent manner. The flow cytometry analysis showed that the blocking effect of SPPHs on the MGC-803 cells was mainly in the G₀/G₁-phase. The morphological changes, disintegration of the cytoskeleton and retardant cell cycles were probably related to the activation of apoptosis. Thus, SPPHs could be promising as a chemopreventive agent due to their ability to promote apoptosis of tumor cells.

Silkworm Pupae: A Functional Food with Health Benefits for Humans

Silkworm pupae are insects that are beneficial to human health, not only for their high nutritional value but, more importantly, for the variety of pharmacological functions they can perform when consumed. Currently, there is a lot of interest in the pharmaceutical applications of silkworm pupae. In recent years, the biological functions of domestic silkworm pupae have gradually been identified and confirmed, especially for their beneficial effects on human health. Studies have found that silkworm pupae have positive effects on liver protection, immune enhancement, antiapoptosis, antitumour, antibacterial, regulation of blood glucose and blood lipids, and lowering of blood pressure. However, the pharmacological mechanisms and systemic safety of silkworm pupae have not been systematically evaluated. In this paper, the nutritional composition of the pupae of the domestic silkworm is first summarised. The pharmacological functions of silkworm pupae and their components are then classified, and their mechanisms of occurrence are described. In addition, we provide a preliminary evaluation of the safety of silkworm pupae, analyse their application prospects, and suggest future directions for further pharmacological function studies. The aim is to generate interest in the promotion of human health through the use of silkworm pupae.

Nano-liposomal zein hydrolysate for improved apoptotic activity and therapeutic index in lung cancer treatment

Lung cancer is one of the most common cancers in the world with a high mortality rate. Zein is a protein compound whose protein isolate is not useful and whose protein hydrolysis produces biological activity. By encapsulating this bioactive compound inside the nanoparticles (NPs), it causes itself to reach the tumor site and destroy it rapidly. In this study, the effects of zein hydrolysate (ZH) and nano-liposomal ZH (N-ZH) were investigated on the human A549 cell line. Western blotting and cell cycle analyses showed that ZH and N-ZH caused cytotoxicity. They induced apoptosis via cell cycle arrest at the G0 phase, as well as significant increases in pro-apoptotic genes, such as Bax, caspase-3, -8, -9, and p53, accompanied with significant decreases in the anti-apoptotic marker Bcl-2. Based on the results, the cytotoxic and anticancer effects of N-ZH were higher than those of free ZH. In conclusion, liposomes improved the performance of ZH and dramatically reduced the IC₅₀ value of ZH. These findings provided the experimental evidence that N-ZH with favorable anticancer activity can be used as a therapeutic agent and strategy for lung cancer treatment in future clinical trials.

A Lipidated Peptide with Mitochondrial Membrane Localization in Human A549 Lung Cells: From Enhanced Cell-Penetrating Properties to Biological Activity Mechanism

Here, a lipidated peptide Pal-pHK-pKV with self-assembly properties and the ability to provoke the disruption of the mitochondrial voltage-dependent anion channel-1 protein (VDAC1)-hexokinase-II (HK-II) complex is reported. The effects of the peptide pHK (N-terminal 15-amino acid fragment of HK-II that specifically binds VDAC1) are compared to those of a designed biomimetic amphiphilic pHK-pKV conjugate (pHK coupled with a cell-penetrating peptide pKV) and Pal-pHK-pKV (a lipidated conjugate modified with a hydrophobic palmitic (Pal) alkyl chain). The Pal-pHK-pKV exhibits a stronger interaction with the membrane as compared to pHK-pKV, which is demonstrated by the Langmuir-Blodgett technique and two-photon excitation microscopy. The amphiphilic peptide derivatives are cytotoxic to the A549 cells, but Pal-pHK-pKV is more cytotoxic. The inhibitory effects of the pHK derivatives on the A549 cells growth are investigated through induced apoptosis pathway, depolarized mitochondrial membrane potential, inhibited glycolysis, and activated caspase. The results of the immunofluorescence evidence the specific mitochondrial targeting by those derivatives.

Products of Sericulture and Their Hypoglycemic Action Evaluated by Using the Silkworm, Bombyx mori (Lepidoptera: Bombycidae), as a Model

Simple Summary

The use of invertebrates as animal models is gaining attention within the scientific community due to numerous advantages during the development of the experiments, low cost of rearing, and fewer ethical problems. The well-documented biology of the silkworm (Bombyx mori) makes this insect an ideal candidate to be used in different fields of research. In this study, we demonstrated the feasibility of using the silkworm to evaluate the hypoglycemic action of various products of sericulture included in the diet after promoting glucose or sucrose-induced hyperglycemia in silkworms. The postprandial antihyperglycemic activity of fibroin, sericin, and powder made from pupae of silkworms is confirmed. These natural products are therefore ideal candidates for the prevention and treatment of diabetes, obesity, and other lifestyle-related diseases.

Abstract

Sericulture generates different natural products with potential medical applications. Silk peptides, worms, or even pupae are commonly employed in traditional Asian medicine with a wide variety of purposes, and some scientific work has been focused on their antidiabetic properties. This work evaluates the postprandial antihyperglycemic activity of fibroin, sericin, and powder made from either larvae or pupae of silkworms, and Bombyx mori L. (Lepidoptera: Bombycidae), employing the silkworm itself as an animal model. The results indicate a reduction in the glucose levels in hemolymph after sucrose or glucose-induced hyperglycemia when these products are included in the diet of the worms.

Nutritional, functional, and allergenic properties of silkworm pupae

Edible insects are a food source that has high nutritional value. Domestic silkworm pupae are an important by-product of sericulture and have a long history as food and feed ingredients in East Asia. Silkworm pupae are a good source of protein, lipids, minerals, and vitamins and are considered a good source of nutrients for humans. Silkworm pupae are a valuable insect source of substances used in healthcare products, medicines, food additives, and animal feed. Because silkworm pupae are being increasingly used in the human diet, potential allergic reactions to the substances they contain must be elucidated. Here, we present an overview of the benefits of silkworm pupae. First, we describe their nutritional value. Second, we report their functional properties and applications, focusing on their potential use in the food and pharmaceutical industries. Finally, we consider the current state of research regarding silkworm pupae-induced allergies.

Benefits and Challenges in the Incorporation of Insects in Food Products

Edible insects are being accepted by a growing number of consumers in recent years not only as a snack but also as a side dish or an ingredient to produce other foods. Most of the edible insects belong to one of these groups of insects such as caterpillars, butterflies, moths, wasps, beetles, crickets, grasshoppers, bees, and ants. Insect properties are analyzed and reported in the articles reviewed here, and one common feature is nutrimental content, which is one of the most important characteristics mentioned, especially proteins, lipids, fiber, and minerals. On the other hand, insects can be used as a substitute for flour of cereals for the enrichment of snacks because of their high content of proteins, lipids, and fiber. Technological properties are not altered when these insects-derived ingredients are added and sensorial analysis is satisfactory, and only in some cases, change in color takes place. Insects can be used as substitute ingredients in meat products; the products obtained have higher mineral content than traditional ones, and some texture properties (like elasticity) can be improved. In extruded products, insects are an alternative source of proteins to feed livestock, showing desirable characteristics. Isolates of proteins of insects have demonstrated bioactive activity, and these can be used to improve food formulations. Bioactive compounds, as antioxidant agents, insulin regulators, and anti-inflammatory peptides, are high-value products that can be obtained from insects. Fatty acids that play a significant role in human health and lipids from insects have showed positive impacts on coronary disease, inflammation, and cancer. Insects can be a vector for foodborne microbial contamination, but the application of good manufacturing practices and effective preservation techniques jointly with the development of appropriate safety regulations will decrease the appearance of such risks. However, allergens presented in some insects are a hazard that must be analyzed and taken into account. Despite all the favorable health-promoting characteristics present in insects and insects-derived ingredients, willingness to consume them has yet to be generalized.

Litter to Leaf: The Unexplored Potential of Silk Byproducts

Silk has remained the most preferred protein fiber since its discovery in 3000 BC. However, the cost, availability, and resources required to rear the silkworms and process silk are imposing considerable constraints on the future of silk. It is often unrealized that apart from the fibers, production and processing of silk are a source for a diverse range of sustainable, biodegradable, and biocompatible polymers. Hence, delineating itself from being the primary source of protein fibers for millenniums, the silk industry worldwide is transitioning into a biobased industry and as a source for pharmaceuticals, biomaterials, cosmetics, food, and energy. Toward this, byproducts (BPs) and co-products (CPs) that are inevitably generated are now being considered to be of immense economic value and could be up to 10 times more valuable than the silk fibers. Here, we elucidate the properties and potential applications of silk BPs and CPs to present the true potential of silkworms and to promote the establishment of silkworm-based bioeconomy and biorefineries.

Effect of heat, enzymatic hydrolysis and acid-alkali treatment on the allergenicity of silkworm pupa protein extract

Silkworm pupae are edible insects with high-quality nutrition in many Asian countries, but consumption of silkworm pupae can cause severe IgE-mediated allergic disease. The aim of this study was to investigate the effect of heat, enzymatic hydrolysis and acid-alkali treatment on the allergenicity of silkworm pupa protein extract (SPPE). Heating reduced the allergenicity of SPPE when the temperature was higher than 60 °C. Spectroscopy studies suggested an unfolded conformation of SPPE with heating, dependent on temperature and time. Enzymatic hydrolysis revealed that SPPE at 25 to 33 kDa contained pepsin- and trypsin-resistant allergens. The results of acid-alkali treatment suggested that low pH can promote hydrolysis of SPPE and decrease its allergenicity. Thus, heat, enzymatic hydrolysis and acid-alkali treatment can significantly decrease the allergenicity of SPPE, with heat-, enzyme- and acid-alkali-resistant allergens at 25 to 33 kDa SPPE. This study can help in the development of methods to prepare silkworm pupa protein.

Edible Oxya chinensis sinuosa-Derived Protein as a Potential Nutraceutical for Anticancer Immunity Improvement

Oxya chinensis sinuosa (Ocs) is consumed as representative edible insects in Asia, but its function in various immune systems remains unclear. This study aimed to demonstrate the immunomodulatory effect, particularly on the innate and adaptive immune response, of Ocs protein (Ocs-P) and to investigate its function as a potent anticancer immunostimulant when administered during the progression stage of colon carcinoma in tumor-bearing mice. Our in vitro results demonstrated that Ocs-P treatment induces phenotypic alteration (increased expression of surface molecules and production of Th1-polarizing cytokines and decreased antigen uptake ability) of dendritic cells (DCs) through the activation of MAPK and NF-κB-dependent signaling pathways. Additionally, Ocs-P-stimulated DCs initiated differentiation of naive T cells into IFN-γ-producing Th1-type T cells effectively and activated cytotoxic CD8⁺ T cell response. In colon carcinoma-bearing mouse models, oral administration of Ocs-P inhibited tumor growth and restored the expression of decreased surface molecules in lineage^-CD11c⁺MHC-II⁺ splenic DCs. Furthermore, Ocs-P administration enhanced the generation of multifunctional CD4⁺ and CD8⁺ T cells expressing Th1-type cytokines (TNF-α, IFN-γ, and IL-2) and the degranulation marker (CD107a). Collectively, these results suggest that Ocs-P demonstrates an immunostimulatory effect and may induce powerful anticancer immunity.

Use of Alcalase in the production of bioactive peptides: A review

This review aims to cover the uses of the commercially available protease Alcalase in the production of biologically active peptides since 2010. Immobilization of Alcalase has also been reviewed, as immobilization of the enzyme may improve the final reaction design enabling the use of more drastic conditions and the reuse of the biocatalyst. That way, this review presents the production, via Alcalase hydrolysis of different proteins, of peptides with antioxidant, angiotensin I-converting enzyme inhibitory, metal binding, antidiabetic, anti-inflammatory and antimicrobial activities (among other bioactivities) and peptides that improve the functional, sensory and nutritional properties of foods. Alcalase has proved to be among the most efficient proteases for this goal, using different protein sources, being especially interesting the use of the protein residues from food industry as feedstock, as this also solves nature pollution problems. Very interestingly, the bioactivities of the protein hydrolysates further improved when Alcalase is used in a combined way with other proteases both in a sequential way or in a simultaneous hydrolysis (something that could be related to the concept of combi-enzymes), as the combination of proteases with different selectivities and specificities enable the production of a larger amount of peptides and of a smaller size.

N6-(2-hydroxyethyl)-Adenosine Induces Apoptosis via ER Stress and Autophagy of Gastric Carcinoma Cells In Vitro and In Vivo

Gastric cancer is the most common malignant tumor of the digestive tract and is great challenge in clinical treatment. N6-(2-Hydroxyethyl)-adenosine (HEA), widely present in various fungi, is a natural adenosine derivative with many biological and pharmacological activities. Here, we assessed the antineoplastic effect of HEA on gastric carcinoma. HEA exerted cytotoxic effects against gastric carcinoma cells (SGC-7901 and AGS) in a dose and time-dependent manner. Additionally, we found that HEA induced reactive oxygen species production and mitochondrial membrane potential depolarization. Moreover, it could trigger caspase-dependent apoptosis, promoting intracellular Ca²⁺-related endoplasmic reticulum (ER) stress and autophagy. On the other hand, HEA could significantly inhibit the growth of transplanted tumors in nude mice and induce apoptosis of tumor tissues cells in vivo. In conclusion, HEA induced apoptosis of gastric carcinoma cells in vitro and in vivo, demonstrating that HEA is a potential chemotherapeutic agent for gastric carcinoma.

Protective effect of a 3 kDa peptide obtained from beef myofibrillar protein using alkaline-AK on neuronal cells

The protective effect of two 3 kDa peptide fractions (AK3KF1 and AK3KF2), obtained from beef myofibrillar protein using an inexpensive enzyme (alkaline-AK) on human neuronal cells (SH-SY5Y) against H₂O₂-induced apoptosis was investigated. These peptides were isolated and further separated by fast protein liquid chromatography (FPLC), and their protective effect against H₂O₂-mediated cell death was measured by determining cell viability, nitric oxide (NO) production, mitochondrial membrane potential (MMP), apoptosis, morphological changes in cell nuclei, and in vitro antioxidant assays. The results indicated that treatment with peptide fractions increased cell viability and MMP, and decreased NO production, fragmentation of cell nuclei, and apoptosis in H₂O₂-treated SH-SY5Y cells. This is the first study to report neuroprotective effects of a peptide obtained from beef myofibrillar protein. The peptide sequence was identified as Thr-Gln-Lys-Lys-Val-Ile-Phe-Cys (TQKKVIFC). Thus, these findings suggest that TQKKVIFC can prevent neuronal cell death and could be useful in preventing neurodegenerative diseases.

Ethanolic extract of Cordyceps cicadae exerts antitumor effect on human gastric cancer SGC-7901 cells by inducing apoptosis, cell cycle arrest and endoplasmic reticulum stress

ETHNOPHARMACOLOGICAL RELEVANCE

Cordyceps cicadae (Miq.) Massee is a traditional Chinese medicine that has been used for approximately 1600 years in China. C. cicadae, a member of the Cordyceps genus, exerts a therapeutic effect on many diseases, such as cancer.

OBJECTIVE

This study aimed to evaluate the antineoplasmic activity of C. cicadae and to identify its molecular mechanism of cell death.

MATERIALS AND METHODS

The toxicity of the ethanolic extract of C. cicadae (EEC) against different cancer cell lines was determined through MTT assay. Human gastric cancer SGC-7901 cells were treated with EEC for 48 h. Cell morphology was examined by using an Olympus phase-contrast microscope. The cell apoptosis was quantified through Annexin V-FITC/PI staining. Cells were stained with PI and then subjected to flow cytometry for the investigation of cell cycle status. Cells were subjected to mitochondrial membrane potential (MMP) assay after incubation with JC-1 probes and to intracellular Ca²⁺ measurement through flow cytometry after incubation with Fluo-3 AM fluorescent probes. Western blot analysis was conducted to quantify the expression of proteins related to apoptosis, cell cycle and endoplasmic reticulum stress. High-performance liquid chromatography (HPLC) analysis was performed to analyse the biological activity components of EEC.

RESULTS

EEC suppressed the proliferation of SGC-7901 cells and induced the development of abnormal morphological features in a dose-dependent manner. Flow cytometry results indicated that EEC treatment caused cell apoptosis and arrested the cell cycle in the S phase. In addition, EEC treatment triggered MMP depolarization and Ca²⁺ overloading in the cytosol of SGC-7901 cells. Western blot analysis demonstrated that EEC increased Bax, AIF, caspase-8, caspase-6 and caspase-3 activities and decreased Bcl-2 activity. The release of cytochrome c from mitochondria was associated with mitochondrial dysfunction, which was caused by the activation of the cell surface receptor Fas and the cleavage of PARP. EEC-induced S phase arrest was associated with the up-regulation of E2F1, cyclin A2, cyclin E and p53 expression levels and the down-regulation of CDK2 expression. In addition, EEC increased the expression of endoplasmic reticulum stress-related proteins, such as calpain-1, caspase-12 and caspase-9. HPLC assay results suggested that EEC contained adenine, uridine, adenosine and N6-(2-Hydroxyethyl)-adenosine.

CONCLUSION

EEC inhibited the proliferation of SGC-7901 cells by inducing caspase-dependent apoptosis, arresting the cell cycle in the S phase and increasing endoplasmic reticulum stress. This study revealed that C. cicadae is a potential natural source of anticancer drugs.

Stromal fibroblast activation protein alpha promotes gastric cancer progression via epithelial-mesenchymal transition through Wnt/ β-catenin pathway

BACKGROUND

To investigate the influence of fibroblast activation protein alpha (FAP) derived from cancer-associated fibroblasts (CAFs), as well as potential mechanism of epithelial mesenchymal transition (EMT), on gastric cancer (GC) progression.

METHODS

Correlation between CAFs-derived FAP and clinical results has been studied by using 60 GC cases. To confirm this relationship, SGC7901 cells were co-cultured with pre-established FAP-overexpressed fibroblasts in vitro and the characteristics including proliferation, migration, invasion and apoptosis abilities were detected subsequently. Meanwhile, SGC and GES1 cells cocultured with FAP-overexpressed fibroblasts were treated with cis-platinum for apoptotic analysis. The underlying EMT was detected by analyzing expression level of E-cadherin, ZO-1, N-cadherin, Vimentin, α-SMA, DKK1 and LEF-1 through western blot and immunofluorescence staining assay. Finally, the tumor-promoting ability of FAP was investigated by utlizing a xenograft gastric cancer nude mouse model.

RESULTS

It show that FAP has a high-risk correlation with the malignant level of clinical outcomes in GC patients. FAP promotes the ability of proliferation, migration, invasion, apoptosis-inhibition of SGC7901 cells and induces apoptosis of GES1 cells in vitro. The mechanism study shows that epithelial markers have been down-regulated and mesenchymal markers and Wnt/β-catenin signal pathway related proteins have been up-regulated. Animal assay suggests that tumor burden has been enhanced by FAP significantly in vivo.

CONCLUSIONS

Stromal FAP could be a potential prognostic biomarker in GC by promoting cancer progression via EMT through Wnt/ β-catenin signal pathway.

Clinical significance and biological roles of cyclins in gastric cancer

Background and aim

Cyclins have been reported to be overexpressed with poor prognosis in several human cancers. However, limited numbers of studies evaluated the expressions and prognostic roles of cyclins in gastric cancer (GC). We aim to evaluate the expressions and prognostic roles of cyclins. Also, further efforts were made to explore biological function of the differentially expressed cyclins.

Methods

Cyclins expressions were analyzed by Oncomine and The Cancer Genome Atlas datasets, and the prognostic roles of cyclins in GC patients were investigated by the Kaplan–Meier Plotter database. Then, a comprehensive PubMed literature search was performed to identify expression and prognosis of cyclins in GC. Biological functions of the differentially expressed cyclins were explored through Enrich R platform, and KEGG and transcription factor were analyzed.

Results

The expression levels of CCNA2 (cyclin A2), CCNB1 (cyclin B1), CCNB2 (cyclin B2), and CCNE1 (cyclin E1) mRNAs were identified to be significantly higher in GC tissues than in normal tissues in both Oncomine and The Cancer Genome Atlas datasets. High expressions of CCNA2, CCNB1, and CCNB2 mRNAs were identified to be related with poor overall survival in Kaplan–Meier Plotter dataset. Evidence from clinical studies showed that CCNB1 was related with overall survival in GC patients. Cyclins were associated with several biological pathways, including cell cycle, p53 signaling pathway, FoxO signaling pathway, viral carcinogenesis, and AMPK signaling pathway. Enrichment analysis also showed that cyclins interacted with some certain transcription factors, such as FOXM1, SIN3A, NFYA, and E2F4.

Conclusion

Based on our results, high expressions of cyclins were related with poor prognosis in GC patients. The above information might be useful for better understanding the clinical and biological roles of cyclins mRNA and guiding individualized treatments for GC patients.