Marine lysozyme from a marine bacterium that inhibits angiogenesis and tumor growth

Fabrication of targeted and pH responsive lysozyme-hyaluronan nanoparticles for 5-fluorouracil and curcumin co-delivery in colorectal cancer therapy

Green nanotechnology is considered a promising method to construct functional materials with significant anticancer activity, while overcoming the shortcomings of traditional synthesis process complexity and high organic solvents consumption. Thus, in this study, we report for the first time the rational design and green synthesis of functionalized 5-fluorouracil and curcumin co-loaded lysozyme-hyaluronan composite colloidal nanoparticles (5-Fu/Cur@LHNPs) for better targeted colorectal cancer therapy with minimized side effects. The functionalized 5-Fu/Cur@LHNPs exhibit stabilized particle size (126.1 nm) with excellent homogeneity (PDI = 0.1), favorable colloidal stabilities, and excellent re-dispersibility. In vitro cell experiments illustrate that the cellular uptake of 5-Fu/Cur@LHNPs was significantly improved and further promoted a higher apoptosis ratio of HCT-116 cells. Compared with the control group, the 5-Fu/Cur@LHNPs formulation group achieved effective inhibition (60.1 %) of colorectal tumor growth. The alcohol-free self-assembly method to construct 5-Fu/Cur@LHNPs is simple and safe for a translational chemotherapy drug, also to promote more robust delivery systems for treating colorectal cancer.

Proteins and their functionalization for finding therapeutic avenues in cancer: Current status and future prospective

Despite the remarkable advancement in the health care sector, cancer remains the second most fatal disease globally. The existing conventional cancer treatments primarily include chemotherapy, which has been associated with little to severe side effects, and radiotherapy, which is usually expensive. To overcome these problems, target-specific nanocarriers have been explored for delivering chemo drugs. However, recent reports on using a few proteins having anticancer activity and further use of them as drug carriers have generated tremendous attention for furthering the research towards cancer therapy. Biomolecules, especially proteins, have emerged as suitable alternatives in cancer treatment due to multiple favourable properties including biocompatibility, biodegradability, and structural flexibility for easy surface functionalization. Several in vitro and in vivo studies have reported that various proteins derived from animal, plant, and bacterial species, demonstrated strong cytotoxic and antiproliferative properties against malignant cells in native and their different structural conformations. Moreover, surface tunable properties of these proteins help to bind a range of anticancer drugs and target ligands, thus making them efficient delivery agents in cancer therapy. Here, we discuss various proteins obtained from common exogenous sources and how they transform into effective anticancer agents. We also comprehensively discuss the tumor-killing mechanisms of different dietary proteins such as bovine α-lactalbumin, hen egg-white lysozyme, and their conjugates. We also articulate how protein nanostructures can be used as carriers for delivering cancer drugs and theranostics, and strategies to be adopted for improving their in vivo delivery and targeting. We further discuss the FDA-approved protein-based anticancer formulations along with those in different phases of clinical trials.

Recent Insights Into the Prognostic and Therapeutic Applications of Lysozymes

Lysozymes are naturally occurring enzymes present in a variety of biological organisms, such as bacteria, fungi, and animal bodily secretions and tissues. It is also the main ingredient of many ethnomedicines. It is well known that lysozymes and lysozyme-like enzymes can be used as anti-bacterial agents by degrading bacterial cell wall peptidoglycan that leads to cell death, and can also inhibit fungi, yeasts, and viruses. In addition to its direct antimicrobial activity, lysozyme is also an important component of the innate immune system in most mammals. Increasing evidence has shown the immune-modulatory effects of lysozymes against infection and inflammation. More recently, studies have revealed the anti-cancer activities of lysozyme in multiple types of tumors, potentially through its immune-modulatory activities. In this review, we summarized the major functions and underlying mechanisms of lysozymes derived from animal and plant sources. We highlighted the therapeutic applications and recent advances of lysozymes in cancers, hypertension, and viral diseases, aiming toseeking alternative therapies for standard medical treatment bypassing side effects. We also evaluated the role of lysozyme as a promising cancer marker for prognosis to indicate the outcomes recurrence for patients.

Noncovalent molecular interactions between antineoplastic drug gemcitabine and a carrier protein identified through spectroscopic and in silico methods

Herein we have studied the noncovalent molecular interactions between hen egg white lysozyme (HEWL) and the commonly employed antineoplastic drug gemcitabine through the cumulative implementation of spectroscopic techniques and in silico approaches. The formation of a complex between HEWL and gemcitabine was made evident by the differences between the UV-visible spectra of the protein and protein-gemcitabine complex. Fluorescence quenching of HEWL by gemcitabine was hardly detectable at room temperature, but it became prominent at higher temperatures. Very low values for the bimolecular quenching constant and the non-reciprocal dependence of quenching on temperature indicated that dynamic quenching was taking place. Analysis of experimental data indicated that the interaction was dominated by hydrophobic forces, while the results of a computational investigation suggested the concomitant contribution of hydrogen bonding. Gemcitabine binding induced modifications of the secondary structure of HEWL by slightly increasing the α-helical content of the protein. Finally, gemcitabine binding site was inferred to be located in HEWL big hydrophobic cavity.

Use of magnetic Fe3O4 nanoparticles coated with bovine serum albumin for the separation of lysozyme from chicken egg white

Fe₃O₄ magnetic nanoparticles modified with tetraethyl orthosilicate and bovine serum albumin (Fe₃O₄@TEOS@BSA) were synthesized and efficiently used to separate lysozyme from egg white. Glutaraldehyde was used to crosslink the bovine serum albumine molecules around the nanoparticles. The surface modifications were attested by transmission electron microscopy, infrared spectroscopy, thermogravimetry analysis, and zeta potential. The material was thermally stable, and its surface charge was pH-dependent. The best lysozyme adsorption and desorption were obtained at pHs 10.0 and 5.0, respectively. The pseudo-second-order model fitted well into the lysozyme adsorption kinetic data and the time for the equilibrium was 15 min. The adsorption equilibrium results were best described by the Freundlich model. Fe₃O₄@TEOS@BSA particles were very efficient to extract lysozyme from chicken egg, according to the SDS-PAGE analyses. The extracted molecules maintained their enzymatic activity in about 90%. Fe₃O₄@TEOS@BSA particles were easily recycled, with their reuse being possible 5 times with the same performance.

Pro-apoptotic action of protein-carbohydrate fraction isolated from coelomic fluid of the earthworm Dendrobaena veneta against human colon adenocarcinoma cells

Earthworm coelomic fluid (CF) is known as a rich source of various bioactive compounds with promising anticancer features. However, it has been demonstrated that CF affects functionality of both, cancer and normal cells. This non-selective activity causes a major problem for medical application of CF. In this study, we present the anticancer activity of the active protein-carbohydrate fraction (AF) isolated from thermally treated CF of earthworm Dendrobaena veneta. The in vitro effect of the AF was examined in human colon model including normal human colon epithelium (CCD 841 CoTr) and human colon adenocarcinoma (HT-29 and LS180) cell lines. We investigated the impact of AF on cell viability neutral red and lactate dehydrogenase assays, morphology May-Grünwald-Giemsa staining assay proliferation MTT tetrazolium salt and BrdU incorporation assays as well as cell cycle progression propidium iodide/RNase staining and the activity of human 20S proteasome the hydrolysis of AMC from a Suc-LLVY-AMC peptide substrate. Additionally, the influence of AF on apoptosis was examined in HT-29 cells by Annexin V/PI, Hoechst 33342 staining and active caspase-3 assays. Our investigation demonstrated that AF at the tested concentration range does not affect the viability and morphology of CCD 841 CoTr cells. Simultaneously, AF inhibits human 20S proteasome activity as well as significantly decreases mitochondrial metabolism, disturbs cell cycle and induces apoptosis via activation of procaspase-3 in HT-29 cancer cells. Obtained results demonstrate the antiproliferative and proapoptotic activity of AF that can be useful in developing therapeutic strategies to treat human colon cancer.

Identification of angiogenesis-inhibiting peptides from Chan Su

Chan Su is a traditional medicine prepared from toxic secretions from the auricular and skin glands of Chinese toads. Previous studies show that active components in Chan Su can inhibit the proliferation of tumor cells. To study the effect of Chan Su peptides on angiogenesis, fresh Chan Su was collected and its component peptides were isolated by an extraction and precipitation method. A high-performance liquid chromatography (HPLC) fingerprint of the Chan Su component peptides revealed that there were more than 18 peptide component peaks. We demonstrate that Chan Su peptides inhibit angiogenesis in vitro by inhibiting human umbilical vein endothelial cell (HUVEC) proliferation and tube formation in a dose-dependent manner. Western blots indicated that Chan Su peptides inhibited the protein expression of VEGF165 and Ras, leading us to conclude that Chan Su peptide components exert anti-angiogenic effects by suppressing the VEGF165-VEGFR2-Ras signalling pathway. Finally, we identified the partial amino acid sequences of seven Chan Su peptides using the shotgun proteomics method.

Lysozyme as the anti-proliferative agent to block the interaction between S100A6 and the RAGE V domain

In this report, using NMR and molecular modeling, we have studied the structure of lysozyme-S100A6 complex and the influence of tranilast [N-(3, 4-dimethoxycinnamoyl) anthranilic acid], an antiallergic drug which binds to lysozyme, on lysozyme-S100A6 and S100A6-RAGE complex formation and, finally, on cell proliferation. We have found that tranilast may block the S100A6-lysozyme interaction and enhance binding of S100A6 to RAGE. Using WST1 assay, we have found that lysozyme, most probably by blocking the interaction between S100A6 and RAGE, inhibits cell proliferation while tranilast may reverse this effect by binding to lysozyme. In conclusion, studies presented in this work, describing the protein-protein/-drug interactions, are of great importance for designing new therapies to treat diseases associated with cell proliferation such as cancers.

Nanocomposites as biomolecules delivery agents in nanomedicine

Nanoparticles (NPs) are atomic clusters of crystalline or amorphous structure that possess unique physical and chemical properties associated with a size range of between 1 and 100 nm. Their nano-sized dimensions, which are in the same range as those of vital biomolecules, such as antibodies, membrane receptors, nucleic acids, and proteins, allow them to interact with different structures within living organisms. Because of these features, numerous nanoparticles are used in medicine as delivery agents for biomolecules. However, off-target drug delivery can cause serious side effects to normal tissues and organs. Considering this issue, it is essential to develop bioengineering strategies to significantly reduce systemic toxicity and improve therapeutic effect. In contrast to passive delivery, nanosystems enable to obtain enhanced therapeutic efficacy, decrease the possibility of drug resistance, and reduce side effects of "conventional" therapy in cancers. The present review provides an overview of the most recent (mostly last 3 years) achievements related to different biomolecules used to enable targeting capabilities of highly diverse nanoparticles. These include monoclonal antibodies, receptor-specific peptides or proteins, deoxyribonucleic acids, ribonucleic acids, [DNA/RNA] aptamers, and small molecules such as folates, and even vitamins or carbohydrates.

Supramolecular nanoassembly of lysozyme and α-lactalbumin (apo α-LA) exhibits selective cytotoxicity and enhanced bioavailability of curcumin to cancer cells

Hybrid supramolecular spherical nanoassembly of hen egg white lysozyme and bovine apo α lactalbumin (SN_LYZ-BLA) was prepared with a mean size of ˜55.2 nm using an optimized desolvation method via chemical crosslinking. The nanoassembly, SN_LYZ-BLA demonstrated dose-dependent reactive oxygen species (ROS) mediated cytotoxicity in multiple cancer cells such as MCF-7, MDA-MB231, HeLa and MG 63. It also demonstrated high loading capacity of a phytochemical based anticancer agent, curcumin (248.8 mg/g) and target-based pH-responsive in vitro drug release with around 85.8% curcumin release observed under acidic condition. Moreover, curcumin loaded SN_LYZ-BLA (SN_LYZ-BLA-CUR) induced cell viability reduction in all cancer cells including mouse melanoma (B16F10) by more than 90% within 24 h. Further, SN_LYZ-BLA and SN_LYZ-BLA-CUR when conjugated with folic acid enhanced the cytotoxicity via folate receptor-based targeting. Both drug loading and release induced conformational change and folding reconstitution of the protein nano-assembly, respectively, which made the whole system an efficient therapeutic agent that works via a dual mode of action. We demonstrated that SN_LYZ-BLA and SN_LYZ-BLA-CUR were highly biocompatible in vitro. Therefore, our supramolecular protein nanoassembly loaded with curcumin could emerge as a comprehensive cancer therapeutics that acts via a strategic mode of dual therapeutic mechanisms.

O-carboxymethyl chitosan Schiff base complexes as affinity ligands for immobilized metal-ion affinity chromatography of lysozyme

We synthesized Ni²⁺-attached O-Carboxymethyl chitosan Schiff base complexes embedded composite cryogels (Ni²⁺-O-CMCS-CCs) by means of polymerization of gel-forming precursors at subzero temperatures. Prepared affinity cryogel showed excellent adsorption performance for lysozyme selected as model protein to test adsorption parameters, demonstrating an adsorption capacity of 244.6 mg/g (15.3 mg/g for Ni²⁺ minus O-CMCS-CCs), with fast adsorption equilibrium within 30 min and good reversibility. The performance of Ni²⁺-O-CMCS-CCs for lysozyme was also evaluated by SDS-PAGE, and a purification efficiency of 86.9% with 89.5% purification yield was determined. The swelling test, FT-IR, and SEM analysis were carried out for the characterization of Ni²⁺-O-CMCS-CCs. At the end of 35 adsorption-desorption cycles, there was no significant change in the adsorption capacity.

A facile and efficient strategy to encapsulate the model basic protein lysozyme into porous CaCO3

A method to load lysozyme, a model of basic protein, with high efficiency and high capacity has been developed by doping heparin into porous CaCO₃ particles. Choosing suitable polyelectrolyte pairs during the layer-by-layer capsule fabrication process avoided losing the loaded lysozyme, and fully retained the bioactivity.

Angiosuppressive properties of marine-derived compounds-a mini review

Angiogenesis, formation of new blood vessels from preexisting one, is a critical step of tumorgenesis of solid tumors. Therefore, antiangiogenic therapy is one of the promising approaches to control tumor growth. In the past 20 years, a lot of compounds have been tested for their antiangiogenic properties. Bevacizumab, Avastin^®, the first antiangiogenic drug approved by the US FDA, has been widely used in clinic for treating cancer. Indeed, many synthetic compounds are highly toxic and exert side effects even though they are effective in inhibiting neovessel formation and cancer cell growth. Using natural compounds or their derivatives is one of the ways to solve these problems. Sinomenine and ginsenosides are common antiangiogenic and anticancer compounds that are extracted from herbal medicines. Recent findings suggested that marine algae-derived natural pigments also possess similar activities. It has been reported that fucoxanthin from Undaria pinnatifida, Siphonaxanthin from Codium fragile, can inhibit angiogenesis and cancer growth effectively. In conclusion, natural compounds derived from marine algae could provide a novel and safe source for new drug development in anticancer and antiangiogenic properties in the future.

LYG1 exerts antitumor function through promoting the activation, proliferation, and function of CD4+ T cells

Identification of novel stimulatory cytokines with antitumor function would have great value in tumor immunotherapy investigations. Here, we report LYG1 (Lysozyme G-like 1) identified through the strategy of Immunogenomics as a novel classical secretory protein with tumor-inhibiting function. LYG1 recombinant protein (rhLYG1) could significantly suppress the growth of B16 tumors in WT B6 mice, but not in SCID-beige mice, Rag1^-/- mice, CD4⁺- or CD8⁺ T cell-deleted mice. It could increase the number of CD4⁺ and CD8⁺ T cells in tumor-infiltrating lymphocytes, tumor-draining lymph nodes, and spleens, and promote IFNγ production by T cells in tumor-bearing mice. In vitro experiments demonstrated that rhLYG1 could directly enhance IFNγ secretion by CD4⁺ T cells, but not CD8⁺ T cells. Moreover, it could promote the activation, proliferation, and IFNγ production of tumor antigen-specific CD4⁺ T cells. The tumor-inhibiting effect of LYG1 was eliminated in Ifng^-/- mice. Furthermore, LYG1 deficiency accelerated B16 and LLC1 tumor growth and inhibited the function of T cells. In summary, our findings reveal a tumor-inhibiting role for LYG1 through promoting the activation, proliferation, and function of CD4⁺ T cells in antitumor immune responses, offering implications for novel tumor immunotherapy.

Marine Enzymes in Cancer: A New Paradigm

Over the last decades, the vast chemical and biodiversity of marine environment has been identified as an important source of new anticancer drugs. The evolution of marine life is a result of competition among microorganisms for space and nutrients in the marine environment, which drives marine microorganisms to generate diverse enzyme systems with unique properties to adapt to harsh conditions of ocean. Therefore, marine-derived sources offer novel enzymes endowed with extraordinary properties. Recent advances in cancer therapy have facilitated enzyme therapy as a promising tool. But, the available information on the use of enzymes derived from marine sources as therapeutic agents for cancer therapy is scanty. The potential utility of marine enzymes in cancer therapy will be discussed in this chapter.

Expression, characterization, and antimicrobial ability of T4 lysozyme from methylotrophic yeast Hansenula polymorpha A16

Lysozyme is an enzyme that is essential for protection against bacterial infections. In this study, a T4 lysozyme gene was cloned into the yeast expression vector pPIC9K under the control of the Pichia pastoris glyceraldehyde-3-phosphate dehydrogenase promoter (pGAP). A Hansenula polymorpha-derived ribosomal DNA (rDNA)-targeting element was inserted into the expression vector and was critical for stable DNA integration into the H. polymorpha chromosome. Recombinant T4 lysozyme was successfully expressed in the yeast H. polymorpha A16; 0.49 g L(-1) secreted recombinant T4 lysozyme was obtained 72 h after incubation in culture broth that had an initial pH of 6.0. Recombinant T4 lysozyme showed lytic activity against the cell walls of the gram positive bacteria, Micrococcus lysodeikticus, and the gram negative bacteria Xanthomonas campestris pv. malvacearum and Xanthomonas oryzae pv. oryzae. The zone of inhibition assay was used to evaluate antimicrobial activity. Mass spectrometry showed the N-terminal sequence of recombinant T4 lysozyme was identical to that of the native enzyme. SDS-PAGE indicated that the molecular mass of recombinant T4 lysozyme was 18.7 kD which corresponds to a monomer of the native enzyme. SDS-PAGE without 0.2 mol L(-1) dithiothreitol treatment detected two bands (15 and 31 kD) suggesting that some recombinant T4 lysozyme formed inter- and intra-molecular disulfide bonds which resulted in loss of enzyme activity.

The Chick Embryo Chorioallantoic Membrane as an In Vivo Assay to Study Antiangiogenesis

Antiangiogenesis, e.g., inhibition of blood vessel growth, is being investigated as a way to prevent the growth of tumors and other angiogenesis-dependent diseases. Pharmacological inhibition interferes with the angiogenic cascade or the immature neovasculature with synthetic or semi-synthetic substances, endogenous inhibitors or biological antagonists.The chick embryo chorioallantoic membrane (CAM) is an extraembryonic membrane, which serves as a gas exchange surface and its function is supported by a dense capillary network. Because its extensive vascularization and easy accessibility, CAM has been used to study morphofunctional aspects of the angiogenesis process in vivo and to study the efficacy and mechanism of action of pro- and anti-angiogenic molecules. The fields of application of CAM in the study of antiangiogenesis, including our personal experience, are illustrated in this review article.