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Plant Lectins in Cancer Treatment: The Case of Viscum album L.
Published in Spyridon E. Kintzios, Maria G. Barberaki, Evangelia A. Flampouri, Plants That Fight Cancer, 2019
Advances in analytical techniques generate significant progress in lectinology, highlighting the insufficiency of existing classification systems to explain and describe new data. The traditional classifications are being supplanted by homology-based systems that incorporate sequence and structural homology plus evolutionary relations in order to categorize the plant lectins (De Hoff et al. 2009). A vast number of plant lectins have been identified and genome-transcriptome analyses revealed that groups are particularly widespread; thus many proteins contain one or more carbohydrate-binding domains, forming complex structures. Thorough analyses of the lectin sequences distinguish 12 different, evolutionary and structurally related carbohydrate-binding domains identified in plants. Every protein domain is characterized by unique folding with highly specific sugar binding sites. The domains are Agaricus bisporus agglutinin homologs, amaranthins, class V chitinase homologs, cyanovirin family, Euonymus europaeus agglutinin family, Galanthus nivalis agglutinin family, proteins with hevein domains, jacalins, proteins with a legume lectin domain, LysM domains, Nicotiana tabacum agglutinin family, and ricin-B family (Van Damme et al. 2008). Representative lectins from each family are listed in Table 8.1.
Human Parainfluenza Virus Infections
Published in Sunit K. Singh, Human Respiratory Viral Infections, 2014
Eric T. Beck, Kelly J. Henrickson
Finally, several compounds have been recently identified as having anti-HPIV activity in vitro. These compounds include novel small molecules, small interfering RNAs, neuraminidase inhibitors (zanamivir), protein synthesis inhibitors (puromycin), nucleic acid synthesis inhibitors, benzithiazole derivatives, carbocyclic-3-deezaadenosine, α-glucosidase inhibitors, a-mannosidase inhibitors, ascorbic acid, calcium elenolate, extracts of Sanicula europaea leaves, and legume lectins (including concanavalin A).318–335 Despite having some in vitro activity, none of these compounds has yet been used in a clinical setting.
Protein Function As Cell Surface And Nuclear Receptor In Human Diseases
Published in Debarshi Kar Mahapatra, Sanjay Kumar Bharti, Medicinal Chemistry with Pharmaceutical Product Development, 2019
Urmila Jarouliya, Raj K. Keservani
Signal transduction through cell-surface receptors is a common feature among living organisms. In plants, several different types of cell-surface receptors perceive diverse signals and stimuli from the environment (both abiotic and biotic) [82]. Among other receptors in plants, one of them is Receptor-like kinases (RLKs) is a class of transmembrane kinases similar in basic structure of receptor tyrosine kinases (RTKs) present in plants. RLKs are a single helical transmembrane segment that connects a ligand binding receptor domain to the outside of the membrane with a kinase protein (Ser/Thr kinase) on the cytoplasmic tail. These RLKs receptors mainly participate in the defense mechanism triggered by infection with a bacterial pathogen [83]. Some major functions of RLK members include developmental processes, such as the regulation of meristem proliferation, organ specification, reproduction and hormone signal transduction. Some of the receptor classes such as the nucleotide-binding site-leucine-rich repeat (NBS-LRR) receptors and histidine kinase receptors, can mediate responses to organic chemicals such as the hormones ethylene and cytokinin. Plants have threats from various pathogenic microbes and resist attacking pathogens through both constitutive and inducible defenses [84]. Pathogen entry into host tissue is a critical, first step in causing plant infection. The major protein of the bacterial flagellum is ‘flagellin’ when any pathogen attacks the plants; the signal to turn on the genes needed for defense against infection is a peptide (flg22) that is released by the breakdown of flagellin protein. Binding of flg22 to the FLS2 receptor of Arabidopsis induces receptor dimerization which, in turn, autophosphorylates the Ser and Thr residues and the downstream effect is activation of a MAPK pathway, this pathway activates a specific transcription factor (Jun, Fos, NFκB) that triggers the synthesis of the proteins that protect against the bacterial infection. Another receptor kinase in plants is lectin receptor kinases which have also a role in innate immunity signaling [85]. These lectin receptor kinases are classified into three types: G, C, and L [86]. G-type lectin receptor kinases are known as S-domain RLKs and are involved in self-incompatibility in flowering plants. C-type (calciumdependent) lectin can be found in a large number of mammalian proteins that mediate innate immune responses and play a major role in pathogen recognition [87], but are rare in plants. L-type lectin receptor kinases (LecRKs) are characterized by an extracellular legume lectin-like domain, a transmembrane domain and an intracellular kinase domain [88]; they were suggested to play a role in abiotic stress signal transduction. In the coming years, researchers need to explore the effect of protein structure on both upstream (ligands and their cofactors) and downstream (effectors and their signaling cascade) targets to develop a clearer picture of plant signal transduction pathways. Information obtained from such studies could lead to novel methods for managing plant disease resistance and signals are increased transcription of specific genes.
Concanavalin A promotes angiogenesis and proliferation in endothelial cells through the Akt/ERK/Cyclin D1 axis
Published in Pharmaceutical Biology, 2022
Jing-Zhou Li, Xiao-Xia Zhou, Wei-Yin Wu, Hai-Feng Qiang, Guo-Sheng Xiao, Yan Wang, Gang Li
Concanavalin A (Con A), a long-studied representative legume lectin, is extracted from jack beans and identified to bind to the surface of glycoproteins and glycolipids in many cell types, including leukocytes, keratinocytes, hepatocytes, and a large number of cell lines, and was also reported to directly stimulate B cells to synthesize DNA and to proliferate (Pink et al. 1983; McMillan et al. 1984; Peschke et al. 1990; Schaumburg-Lever 1990). Thus far, Con A has been generated rising attention for its anti-proliferative and antitumor activities towards various types of cancer cells. Con A has been reported to kill tumour cells targeting apoptosis, autophagy, anti-angiogenesis, and immunomodulatory (Li et al. 2011). However, the role of Con A on cell cycle progression and angiogenic activity in ECs was barely reported.
An Overview of Hepatocellular Carcinoma with Emphasis on Dietary Products and Herbal Remedies
Published in Nutrition and Cancer, 2022
Deepa S. Mandlik, Satish K. Mandlik
The research looked at the anti-proliferative properties of aqueous extracts from French bean aerial sections (Phaseolus vulgaris). The aqueous extracts showed strong antioxidant activity at 400 and 800 mg/mL doses and inhibited the development of HepG2 cells (62). The seed coats of P. vulgaris yielded several compounds, including triterpenoids and flavonoids, according to phytochemical review. Several compounds isolated from P. vulgaris showed anti-proliferative activity (63). The lectins are the most common protein found in legumes. Due to its assorted pharmacological roles such as antitumor, anti-HIV and antibacterial properties, lectin has gained a lot of attention as a therapeutic agent in recent years. The hemagglutinin extracted from the seeds of P. vulgaris had a moderate inhibitory effect on HepG2 cell growth but did not affect normal liver cells (64). According to their research, BTKL’s (legume lectin from the seeds) antitumor activities against HepG2 cells may be mediated by three mechanisms as inducing apoptosis and necrosis, promoting nitric oxide development through upregulation of iNOS and triggering the release of proinflammatory cytokines such as interleukin (IL)-1, IL-2, tumor necrosis factor (TNF)-α and Interferon (INF)-γ (65). A hemagglutinin isolated from P. vulgaris was found to have greater anti-proliferative activity than concanavalin A in the HepG2 cancer cells (66).
Wisteria floribunda agglutinin positive glycobiomarkers: a unique lectin as a serum biomarker probe in various diseases
Published in Expert Review of Proteomics, 2018
Hisashi Narimatsu, Takashi Sato
WFA, which is a legume lectin purified from W. floribunda seeds, is known to bind to Gal/GalNAc glycan moieties. WFA has been identified as an optimal biomarker probe in several other diseases, including liver fibrosis, liver cirrhosis (LC), cholangiocarcinoma (CC), ovarian cancer, IgA nephropathy (IgAN), and prostate cancer. In each of these diseases, WFA was able to detect disease-associated glyco-alterations on glycoproteins in patient serum. Several studies have found WFA to be an effective probe for distinguishing patients with several diseases, including cancer, from controls (Figure 1). This review summarizes the WFA-positive glycobiomarkers in several diseases and molecular characterization of the probe lectin, WFA.