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Gastrointestinal cancer (GIC), including gastric cancer and colorectal cancer, is a common malignant tumor originating from the gastrointestinal epithelium. Although the pathogenesis of GIC has not been fully elucidated, angiogenesis is recognized as the key pathological basis for the growth, invasion and metastasis of cancer cells, and GIC angiogenesis is closely related to vascular endothelial growth factor family, hypoxia-inducible factor family, fibroblast growth factor family and matrix metalloproteinase family. Recently, many natural products have shown a wide range of pharmacological biological activities against GIC. In this review, the effects and mechanisms of natural compounds on the angiogenesis of gastric and colorectal cancer were summarized. The results show that some natural compounds, especially gallic catechin gallate, astragaloside and curcumin, can effectively inhibit angiogenesis; the HIF-1α/VEGF, COX-2/PGE2, HGF/c-Met and PI3K/Akt/mTOR are involved in these inhibition effects. This review examines the anti-angiogenesis potential of natural products in the GIC treatment and provides clues to the development of vascular targeted agents.

Gastric cancer, a common malignant disease, seriously endangers human health and life. The high mortality rate due to gastric cancer can be attributed to a lack of effective therapeutic drugs. Cancer cells utilize the glycolytic pathway to produce energy even under aerobic conditions, commonly referred to as the Warburg effect, which is a characteristic of gastric cancer. The identification of new targets based on the glycolytic pathway for the treatment of gastric cancer is a viable option, and accumulating evidence has shown that phytochemicals have extensive anti-glycolytic properties. We reviewed the effects and mechanisms of action of phytochemicals on aerobic glycolysis in gastric cancer cells. Phytochemicals can effectively inhibit aerobic glycolysis in gastric cancer cells, suppress cell proliferation and migration, and promote apoptosis, via the PI3K/Akt, c-Myc, p53, and other signaling pathways. These pathways affect the expressions of HIF-1α, HK2, LDH, and other glycolysis-related proteins. This review further assesses the potential of using plant-derived compounds for the treatment of gastric cancer and sheds insight into the development of new drugs.

Berberis amurensis Rupr. is used to treat cancer as a traditional herbal medicine. Berbamine (BBM) is a natural bisbenzylisoquinoline alkaloid extracted from Berberis amurensis which possesses multiple pharmacological activity including anticancer.To investigate the influence of BBM on the progression of colorectal cancer (CRC) and further explore the underlying mechanism of BBM based on the RTKs/Akt signaling pathway.In vitro, cell viability and colony formation were conducted to detect BBM inhibitory of CRC cell lines. Transwell was detected the ability of migration and invasion by BBM. Apoptosis detection assay, cell cycle assay and the measurement of ROS were detected to confirm the inductive effect of cell apoptosis. RT-qPCR and Western blot to clarify the specific mechanism of anticancer. Finally, we conducted HE staining, Ki67, Tunnel and immunochemistry were confirmed the anti-colorectal cancer activity of BBM from vivo study.We found that BBM could inhibit CRC cell lines growth. Moreover, BBM presented an inhibitory effect the ability of migration and invasion in CRC cells. Furthermore, the occurrence of apoptosis was involved in the anti-colorectal cancer role of BBM. BBM also triggered ROS accumulation in CRC cells that might be a key factor for the inductive effect of BBM in cell apoptosis. Cell cycle assay revealed that BBM induced the arrest of G1-S phase and increased the p21 levels but decreased CyclinE1, CyclinE2, CDK6, CyclinD1. RT-qPCR manifested that the down-regulation effect of BBM on AKT1, EGFR, PDGFRα and FGFR4 genes. The results also showed that BBM could decreased the expression levels of phosphor-AKT, PDGFRα, PDGFRβ, EGFR, FGFR3 and FGFR4 which belong to RTKs family. Consistently, BBM remarkably suppressed tumor xenograft growth in nude mice.Taken together, all the results as presented above suggest that BBM as a novel multitargeted receptor tyrosine kinase inhibitor plays a crucial role in the inhibitory effect of CRC and may be a promising therapeutic agent for the CRC in clinic.

Background: Blocking and even reversing gastric precancerous lesions (GPL) is a key measure to lower the incidence of gastric cancer. Atractylenolide III (AT-III) is a mainly active component of the Atractylodes rhizome and has been widely used in tumor treatment. However, the effects of AT-III on GPL and its mechanisms have not been reported.Methods: H & E staining and AB-PAS staining were employed to evaluate the histopathology in the gastric mucosa. In parallel, CD34 immunostaining was performed for angiogenesis assessment, and transmission electron microscope for microvessel ultrastructural observation. Investigation for the possible mechanism in vivo and in vitro was conducted using immunohistochemistry, RT-qPCR and western blotting.Results: In most GPL specimens, AT-III treatment reduced microvascular abnormalities and attenuated early angiogenesis, with the regression of most intestinal metaplasia and partial dysplasia. Meanwhile, the expression of VEGF-A and HIF-1α was enhanced in GPL samples of model rats, and their expressions were decreased in AT-III-treated GPL rats. Moreover, DLL4 mRNA and protein expression were higher in GPL rats than in control rats. DLL4 protein expression was significantly enhanced in human GPL tissues. In addition, AT-III treatment could diminish DLL4 mRNA level and protein expression in the MNNG-induced GPL rats. In vitro study showed that in AGS and HGC-27 cells, DLL4 mRNA level and protein expression were significantly decreased after AT-III treatment. However, AT-III had no significant regulatory effect on Notch1 and Notch4.Conclusion: AT-III treatment is beneficial in lessening gastric precancerous lesions and attenuating angiogenesis in rats, and that may be contributed by the decrease of angiogenesis-associated HIF-1α and VEGF-A, and downregulation of DLL4.

Cancer stem cells (CSCs) are strongly associated with high tumourigenicity, chemotherapy or radiotherapy resistance, and metastasis and recurrence, particularly in colorectal cancer (CRC). Therefore, targeting CSCs may be a promising approach. Recently, discovery and research on phytochemicals that effectively target colorectal CSCs have been gaining popularity because of their broad safety profile and multi-target and multi-pathway modes of action.This review aimed to elucidate and summarise the effects and mechanisms of phytochemicals with potential anti-CSC agents that could contribute to the better management of CRC.We reviewed PubMed, EMBASE, Web of Science, Ovid, ScienceDirect and China National Knowledge Infrastructure databases from the original publication date to March 2022 to review the mechanisms by which phytochemicals inhibit CRC progression by targeting CSCs and their key signalling pathways. Phytochemicals were classified and summarised based on the mechanisms of action.We observed that phytochemicals could affect the biological properties of colorectal CSCs. Phytochemicals significantly inhibit self-renewal, migration, invasion, colony formation, and chemoresistance and induce apoptosis and differentiation of CSCs by regulating the Wnt/β-catenin pathway (e.g., diallyl trisulfide and genistein), the phosphatidylinositol-3-kinase/protein kinase B/mammalian target of rapamycin pathway (e.g., caffeic acid and piperlongumine), the neurogenic locus notch homolog protein pathway (e.g., honokiol, quercetin, and α-mangostin), the Janus kinase-signal transducer and activator of transcription pathway (e.g., curcumin, morin, and ursolic acid), and other key signalling pathways. It is worth noting that several phytochemicals, such as resveratrol, silibinin, evodiamine, and thymoquinone, highlight multi-target and multi-pathway effects in restraining the malignant biological behaviour of CSCs.This review demonstrates the potential of targeted therapies for colorectal CSCs using phytochemicals. Phytochemicals could serve as novel therapeutic agents for CRC and aid in drug development.

Ginsenoside Rg3 (GRg3) is a ginsenoside extracted from Panax ginseng. GRg3 displays multiple pharmacological properties, such as antitumor, anti-inflammatory, antioxidative and antifibrotic properties. However, whether GRg3 inhibits angiogenesis in gastric precancerous lesions (GPLs) and the possible mechanisms remain unknown. GRg3 attenuated gastric intestinal metaplasia and gastric dysplasia, the hallmark of GPL pathology, in rats with MNNG-ammonia compound induced GPLs. Increased CD34+ microvessel density and VEGF expression, which indicate the presence of angiogenesis, were evident in the rats with GPLs. GRg3 administration reduced VEGF protein expression and CD34+ microvessel density. In addition, GRg3 was capable of attenuating microvascular abnormalities. Data analysis revealed that enhanced protein expression of GLUT1, GLUT3 and GLUT4 were present in both human and animal GPL specimens. The administration of GRg3 caused significant decreases in the mRNA and protein expression levels of GLUT1 and GLUT4 in the rats with GPLs. However, the GRg3-treated rats with GPLs did not demonstrate regulatory effects on GLUT3, GLUT6, GLUT10, and GLUT12. Consistent with in vitro results, GRg3 administration significantly reduced the protein expression levels of GLUT1 and GLUT4 in both AGS and HGC-27 human gastric cancer cells in vitro. In conclusion, GRg3 can attenuate angiogenesis and temper microvascular abnormalities in rats with GPLs, which may be associated with its inhibition on the aberrant activation of GLUT1 and GLUT4.

Gallic acid (GA) is a natural polyphenolic compound derived from Rhus chinensis Mill. with a variety of biological activities such as astringent sweat, cough, dysentery, hemostasis, and detoxification, and is widely used in China as a treatment for cough, bleeding, and gastrointestinal disorders. In recent years, the anticancer activity of GA has been demonstrated in a variety of cancers, affecting multiple cellular pathways associated with cancer onset, development and progression.To investigate the role and potential mechanism of GA on gastric precancerous lesions (GPL), the key turning point of gastritis to gastric cancer, with the aim of delaying, blocking or reversing the dynamic overall process of "inflammation-cancer transformation" and thus blocking GPL to prevent the development of gastric cancer.In this study, we established N-Nitroso-N-methylurea (MNU)-induced GPL mice model and induced precancerous lesions of gastric cancer cells (MC), i.e. epithelial mesenchymal transition (EMT), in human gastric mucosal epithelial cells (GES-1) with N-methyl-N'-nitro-N-nitrosoguanidine (MNNG). We used conventional pathology, immunohistochemistry, RNA sequencing, Western blot and other techniques to study the therapeutic effect of GA on GPL and its possiblemechanism in vitro and in vivo.The results showed that compared with normal GES-1 cells, MC cells had the characteristics of malignant cells such as abnormal proliferation, invasion and metastasis, accompanied by decreased expression of EMT-related protein E-cadherin and increased expression of N-cadherin and Vimentin. GA can inhibit the malignant behavior of MC cell proliferation and induce its G0/G1 phase arrest, which is achieved by downregulating the Wnt/β-catenin signaling pathway and thereby inhibiting the EMT process. However, when we incubated with the Wnt pathway activator (Wnt agonist 1), the effect of GA was reversed. Furthermore, analysis of human gastric specimens showed that activation of the Wnt/β-catenin pathway was significantly associated with GPL pathological changes. Meanwhile, GA reversed MNU-induced intestinal metaplasia and partial dysplasia in GPL mice.Taken together, these results indicate that GA prevents the occurrence and development of GPL by inhibiting the Wnt/β-catenin signaling pathway and then inhibiting the EMT process, which may become potential candidates for the treatment of GPL.

Mitochondria are the energy factories of cells with the ability to modulate the cell cycle, cellular differentiation, signal transduction, growth, and apoptosis. Existing drugs targeting mitochondria in cancer treatment have disadvantages of drug resistance and side effects. Phytochemicals, which are widely found in plants, are bioactive compounds that could facilitate the development of new drugs for gastric cancer. Studies have shown that some phytochemicals can suppress the development of gastric cancer.We searched for data from PubMed, China National Knowledge Infrastructure, Web of Science, and Embase databases from initial establishment to December 2021 to review the mechanism by which phytochemicals suppress gastric cancer cell growth by modulating mitochondrial function. Phytochemicals were classified and summarized by their mechanisms of action.Phytochemicals can interfere with mitochondria through several mechanisms to reach the goal of promoting apoptosis in gastric cancer cells. Some phytochemicals, e.g., daidzein and tetrandrine promoted cytochrome c spillover into the cytoplasm by modulating the members of the B-cell lymphoma-2 protein family and induced apoptotic body activity by activating the caspase protein family. Phytochemicals (e.g., celastrol and shikonin) could promote the accumulation of reactive oxygen species and reduce the mitochondrial membrane potential. Several phytochemicals (e.g., berberine and oleanolic acid) activated mitochondrial apoptotic submission via the phosphatidylinositol-3-kinase/Akt signaling pathway, thereby triggering apoptosis in gastric cancer cells. Several well-known phytochemicals that target mitochondria, including berberine, ginsenoside, and baicalein, showed the advantages of multiple targets, high efficacy, and fewer side effects.Phytochemicals could target the mitochondria in the treatment of gastric cancer, providing potential directions and evidence for clinical translation. Drug discovery focused on phytochemicals has great potential to break barriers in cancer treatment.

Background: Seeking novel and effective therapies for gastric precancerous lesions (GPL) is crucial to reducing the incidence of gastric cancer. Ginsenoside Rb1 (GRb1) is a major ginsenoside in ginseng and has been proved to possess multiple bioactivities. However, whether GRb1 could protect against GPL and the underlying mechanisms have not been explored.Methods: We evaluated the effects of GRb1 on gastric precancerous lesions in rats on macroscopic, microscopic and ultramicroscopic levels. Then, an antibody array was employed to screen differential expression proteins (DEPs). Validation for the targeting DEP and investigation for the possible mechanism was conducted using immunohistochemistry, qRT-PCR, TUNEL apoptosis assay, immunoprecipitation and immunoblotting.Results: GRb1 was found to reverse intestinal metaplasia and a portion of dysplasia in the MNNG-induced GPL rats. The antibody array assay revealed seven DEPs in GPL rats as compared to control rats (5 DEPs were up-regulated, while two DEPs were down-regulated). Among the DEPs, β-catenin, beta-NGF and FSTL1 were significantly down-regulated after GRb1 administration. Our validation results revealed that enhanced protein expression and nuclear translocation of β-catenin were present in animal GPL samples. In addition, analysis of human gastric specimens demonstrated that β-catenin up-regulation and nuclear translocation were significantly associated with advanced GPL pathology. GRb1 intervention not only decreased protein expression and nuclear translocation of β-catenin, but interfered with β-catenin/TCF4 interaction. Along with this, declined transcriptional and protein expression levels of downstream target genes including c-myc, cyclin D1 and Birc5 were observed in GRb1-treated GPL rats.Conclusion: GRb1 is capable of preventing the occurrence and progression of GPL, which might be contributed by diminishing protein expression and nuclear translocation of β-catenin and interfering with β-catenin/TCF4 interaction.

Nan Zhang,* Yanyang Liu,* Yuyi Wang, Maoyuan Zhao, Li Tu, Feng Luo Department of Medical Oncology, Cancer Center, Lung Cancer Center and State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, Sichuan, People’s Republic of China *These authors contributed equally to this work Objective: Epithelial–mesenchymal transition (EMT) is a crucial driver of tumor progression. Tumor growth factor-beta 1 (TGF-β1) is an important factor in EMT induction in tumorigenesis. The targeting of EMT may, therefore, represent a promising approach in anticancer treatment. Methods: In this study, we determined the effect of decitabine, a DNA methyltransferase inhibitor, on TGF-β1-induced EMT in non-small-cell lung cancer (NSCLC) PC9 and A549 cells. We also assessed the involvement of the miR-200/ZEB axis. Results: Decitabine reversed TGF-β1-induced EMT in PC9 cells, but not in A549 cells. This phenomenon was associated with epigenetic changes in the miR-200 family, which regulated EMT by altering the expression of ZEB1 and ZEB2. TGF-β1 induced aberrant methylation in miR-200 promoters, leading to EMT in PC9 cells. Decitabine attenuated this effect and inhibited tumor cell migration in vitro and in vivo. In A549 cells, however, neither TGF-β1 nor decitabine exhibited an effect on miR-200 promoter methylation. Conclusion: Our findings suggest that epigenetic regulation of the miR-200/ZEB axis is responsible for EMT induction by TGF-β1 in PC9 cells. Decitabine inhibits EMT in NSCLC cell PC9 through its epigenetic-based therapeutic activity. Keywords: DNA methyltransferase inhibitor, EMT, miRNA, epigenetics, NSCLC