Polysaccharides from Ulva prolifera O.F. Müller inhibit cell proliferation via activating MAPK signaling in A549 and H1650 cells

MYC Oncogene: A Druggable Target for Treating Cancers with Natural Products

Various diseases, including cancers, age-associated disorders, and acute liver failure, have been linked to the oncogene, MYC. Animal testing and clinical trials have shown that sustained tumor volume reduction can be achieved when MYC is inactivated, and different combinations of therapeutic agents including MYC inhibitors are currently being developed. In this review, we first provide a summary of the multiple biological functions of the MYC oncoprotein in cancer treatment, highlighting that the equilibrium points of the MYC/MAX, MIZ1/MYC/MAX, and MAD (MNT)/MAX complexes have further potential in cancer treatment that could be used to restrain MYC oncogene expression and its functions in tumorigenesis. We also discuss the multifunctional capacity of MYC in various cellular cancer processes, including its influences on immune response, metabolism, cell cycle, apoptosis, autophagy, pyroptosis, metastasis, angiogenesis, multidrug resistance, and intestinal flora. Moreover, we summarize the MYC therapy patent landscape and emphasize the potential of MYC as a druggable target, using herbal medicine modulators. Finally, we describe pending challenges and future perspectives in biomedical research, involving the development of therapeutic approaches to modulate MYC or its targeted genes. Patients with cancers driven by MYC signaling may benefit from therapies targeting these pathways, which could delay cancerous growth and recover antitumor immune responses.

Research Progress on the Anticancer Activity of Plant Polysaccharides

Tumor is a serious threat to human health, with extremely high morbidity and mortality rates. However, tumor treatment is challenging, and the development of antitumor drugs has always been a significant research focus. Plant polysaccharides are known to possess various biological activities. They have many pharmacological properties such as immunomodulation, antitumor, antiviral, antioxidative, antithrombotic, and antiradiation effects, reduction of blood pressure and blood sugar levels, and protection from liver injury. Among these effects, the antitumor effect of plant polysaccharides has been widely studied. Plant polysaccharides can inhibit tumor proliferation and growth by inhibiting tumor cell invasion and metastasis, inducing cell apoptosis, affecting the cell cycle, and regulating the tumor microenvironment. They also have the characteristics of safety, high efficiency, and low toxicity, which can alleviate, to a certain extent, the adverse reactions caused by traditional tumor treatment methods such as surgery, radiotherapy, and chemotherapy. Therefore, this paper systematically summarizes the direct antitumor effects of plant polysaccharides, their regulatory effects on the tumor microenvironment, and intervening many common high-incidence tumors in other ways. It also provides data support for the administration of plant polysaccharides in modern tumor drug therapy, enabling the identification of new targets and development of new drugs for tumor therapy.

Antimetastatic effect of fucoidan against non-small cell lung cancer by suppressing non-receptor tyrosine kinase and extracellular signal-related kinase pathway

BACKGROUND/OBJECTIVES

Fucoidan, a polysaccharide content in brown algae, has been reported to inhibit the growth of cancer cells. The present study aimed to investigate the suppression effects of fucoidan on A549 non-small cell lung cancer cells migration.

MATERIALS/METHODS

The anti-migratory activity of fucoidan in A549 cells was examined by wound healing assay and phalloidin-rhodamine staining in response to fucoidan (0-100 µg/mL) treatment for 48 h. Western blot analysis was performed to clarify the protein expressions relevant to migratory activity.

RESULTS

Fucoidan (25-100 µg/mL) significantly suppressed A549 cells migration together with reduced the intensity of phalloidin-rhodamine which detect filopodia and lamellipodia protrusions at 48 h of treatment. The protein expression indicated that fucoidan significantly suppressed the phosphorylation of focal adhesion kinase (FAK), Src, and extracellular signal-related kinase (ERK). In addition, the phosphorylation of p38 in A549 cells was found to be increased.

CONCLUSIONS

Our data conclude that fucoidan exhibits anti-migratory activities against lung cancer A549 cells mediated by inhibiting ERK1/2 and FAK-Src pathway.

Preparation and Characterization of an Anticancer Peptide from Oriental Tonic Food Enteromorpha prolifera

Enteromorpha prolifera (E. prolifera), a tonic food in East Asian countries, is frequently studied for their pharmaceutical and healthcare applications. However, limited research has focused on antitumor peptides derived from this edible seaweed. In this study, we aimed to investigate the anticancer properties of peptides isolated from the hydrolysate of E. prolifera generated by a plethora of proteases including trypsin, papain, bromelain, and alkaline protease. The results showed that the hydrolysate produced by papain digestion exhibited remarkably stronger anticancer activity and was subjected to further purification by ultrafiltration and sequential chromatography. One heptapeptide, designated HTDT-6-2-3-2, showed significant antiproliferation activity towards several human cancer cell lines. The IC50 values for NCI-H460, HepG2, and A549 were 0.3686 ± 0.0935 mg/mL, 1.2564 ± 0.0548 mg/mL, and 0.9867 ± 0.0857 mg/mL, respectively. Moreover, results from flow cytometry confirmed that cell apoptosis was induced by HTDT-6-2-3-2 in a dose-dependent manner. The amino acid sequence for this heptapeptide, GPLGAGP, was characterized by Edman degradation and further verified by Liquid Chromatography-Tandem Mass Spectrometry. In silico analysis results suggested that XIAP could be a potential target for HTDT-6-2-3-2. Molecular docking simulation showed that HTDT-6-2-3-2 could occupy a shallow pocket in the BIR3 domain of XIAP, which is involved in the inhibitory effect of caspase-9 activation. In conclusion, this E. prolifera derived peptide exhibited strong anticancer properties, which could be explored for pharmaceutical applications.

Understanding immune-modulatory efficacy in vitro

Boosting or suppressing our immune system represents an attractive adjunct in the treatment of infections including SARS-CoV-2, cancer, AIDS, malnutrition, age related problems and some inflammatory disorders. Thus, there has been a growing interest in exploring and developing novel drugs, natural or synthetic, that can manipulate our defence mechanism. Many of such studies, reported till date, have been designed to explore effect of the therapeutic on function of macrophages, being a key component in innate immune system. Indeed, RAW264.7, J774A.1, THP-1 and U937 cell lines act as ideal model systems for preliminary investigation and selection of dose for in vivo studies. Several bioassays have been standardized so far where many techniques require high throughput instruments, cost effective reagents and technical assistance that may hinder many scholars to perform a method demanding compilation of available protocols. In this review, we have taken an attempt for the first time to congregate commonly used in vitro immune-modulating techniques explaining their principles. The study detected that among about 40 different assays and more than 150 sets of primers, the methods of cell proliferation by MTT, phagocytosis by neutral red, NO detection by Griess reaction and estimation of expression of TLRs, COX-2, iNOS, TNF-α, IL-6 and IL-1β by PCR have been the most widely used to screen the therapeutics under investigation.