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Chi Y, Li Y, Ding C, Liu X, Luo M, Wang Z, Bi Y, Luo S. Structural and biofunctional diversity of sulfated polysaccharides from the genus Codium (Bryopsidales, Chlorophyta): A review. Int J Biol Macromol 2024; 263:130364. [PMID: 38401579 DOI: 10.1016/j.ijbiomac.2024.130364] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2023] [Revised: 01/14/2024] [Accepted: 02/20/2024] [Indexed: 02/26/2024]
Abstract
It is believed that polysaccharides will become a focal point for future production of food, pharmaceuticals, and materials due to their ubiquitous and renewable nature, as well as their exceptional properties that have been extensively validated in the fields of nutrition, healthcare, and materials. Sulfated polysaccharides derived from seaweed sources have attracted considerable attention owing to their distinctive structures and properties. The genus Codium, represented by the species C. fragile, holds significance as a vital economic green seaweed and serves as a traditional Chinese medicinal herb. To date, the cell walls of the genus Codium have been found to contain at least four types of sulfated polysaccharides, specifically pyruvylated β-d-galactan sulfates, sulfated arabinogalactans, sulfated β-l-arabinans, and sulfated β-d-mannans. These sulfated polysaccharides exhibit diverse biofunctions, including anticoagulant, immune-enhancing, anticancer, antioxidant activities, and drug-carrying capacity. This review explores the structural and biofunctional diversity of sulfated polysaccharides derived from the genus Codium. Additionally, in addressing the impending challenges within the industrialization of these polysaccharides, encompassing concerns regarding scale-up production and quality control, we outline potential strategies to address these challenges from the perspectives of raw materials, extraction processes, purification technologies, and methods for quality control.
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Affiliation(s)
- Yongzhou Chi
- School of Life Science and Food Engineering, Huaiyin Institute of Technology, Huai'an, Jiangsu 223003, China.
| | - Yang Li
- School of Life Science and Food Engineering, Huaiyin Institute of Technology, Huai'an, Jiangsu 223003, China
| | - Chengcheng Ding
- School of Life Science and Food Engineering, Huaiyin Institute of Technology, Huai'an, Jiangsu 223003, China
| | - Xiao Liu
- School of Life Science and Food Engineering, Huaiyin Institute of Technology, Huai'an, Jiangsu 223003, China
| | - Meilin Luo
- School of Life Science and Food Engineering, Huaiyin Institute of Technology, Huai'an, Jiangsu 223003, China
| | - Zhaoyu Wang
- School of Life Science and Food Engineering, Huaiyin Institute of Technology, Huai'an, Jiangsu 223003, China
| | - Yanhong Bi
- School of Life Science and Food Engineering, Huaiyin Institute of Technology, Huai'an, Jiangsu 223003, China
| | - Si Luo
- School of Life Science and Food Engineering, Huaiyin Institute of Technology, Huai'an, Jiangsu 223003, China
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Sun A, Chen Y, Tian X, Lin Q. The Role of HECT E3 Ubiquitin Ligases in Colorectal Cancer. Biomedicines 2023; 11:biomedicines11020478. [PMID: 36831013 PMCID: PMC9953483 DOI: 10.3390/biomedicines11020478] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2022] [Revised: 01/31/2023] [Accepted: 02/06/2023] [Indexed: 02/11/2023] Open
Abstract
Colorectal cancer (CRC) is estimated to rank as the second reason for cancer-related deaths, and the prognosis of CRC patients remains unsatisfactory. Numerous studies on gastrointestinal cell biology have shown that the E3 ligase-mediated ubiquitination exerts key functions in the pathogenesis of CRC. The homologous to E6-associated protein C-terminus (HECT) family E3 ligases are a major group of E3 enzymes, featured with the presence of a catalytic HECT domain, which participate in multiple cellular processes; thus, alterations in HECT E3 ligases in function or expression are closely related to the occurrence and development of many human malignancies, including-but not limited to-CRC. In this review, we summarize the potential role of HECT E3 ligases in colorectal carcinogenesis and the related underlying molecular mechanism to expand our understanding of their pathological functions. Exploiting specific inhibitors targeting HECT E3 ligases could be a potential therapeutic strategy for CRC therapy in the future.
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Potential Prebiotic and Anti-Obesity Effects of Codium fragile Extract. APPLIED SCIENCES-BASEL 2022. [DOI: 10.3390/app12030959] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Polysaccharides from marine algae exhibit beneficial biological activities. In this study, we examined the effect of Codium fragile extract (CFE) on prebiotic and anti-obesity activity through in vitro experiments. CFE increases the growth of specific beneficial microbial populations with concomitant decrease in pathogenic microbes. Further, total phenolic content (TPC), total flavonoid content (TFC), and DPPH radical scavenging activity (DPPH activity) after fermentation with CFE as the carbon source were higher than for glucose as the control. Moreover, CFE inhibited adipocyte differentiation by inducing differentiation-related factors when the induction of 3T3-L1 preadipocytes into adipocytes was induced. Therefore, we suggest that CFE can be used as a prebiotic material with an anti-obesity effect for human health.
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Razeghian E, Suksatan W, Sulaiman Rahman H, Bokov DO, Abdelbasset WK, Hassanzadeh A, Marofi F, Yazdanifar M, Jarahian M. Harnessing TRAIL-Induced Apoptosis Pathway for Cancer Immunotherapy and Associated Challenges. Front Immunol 2021; 12:699746. [PMID: 34489946 PMCID: PMC8417882 DOI: 10.3389/fimmu.2021.699746] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2021] [Accepted: 08/05/2021] [Indexed: 01/04/2023] Open
Abstract
The immune cytokine tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) has attracted rapidly evolving attention as a cancer treatment modality because of its competence to selectively eliminate tumor cells without instigating toxicity in vivo. TRAIL has revealed encouraging promise in preclinical reports in animal models as a cancer treatment option; however, the foremost constraint of the TRAIL therapy is the advancement of TRAIL resistance through a myriad of mechanisms in tumor cells. Investigations have documented that improvement of the expression of anti-apoptotic proteins and survival or proliferation involved signaling pathways concurrently suppressing the expression of pro-apoptotic proteins along with down-regulation of expression of TRAILR1 and TRAILR2, also known as death receptor 4 and 5 (DR4/5) are reliable for tumor cells resistance to TRAIL. Therefore, it seems that the development of a therapeutic approach for overcoming TRAIL resistance is of paramount importance. Studies currently have shown that combined treatment with anti-tumor agents, ranging from synthetic agents to natural products, and TRAIL could result in induction of apoptosis in TRAIL-resistant cells. Also, human mesenchymal stem/stromal cells (MSCs) engineered to generate and deliver TRAIL can provide both targeted and continued delivery of this apoptosis-inducing cytokine. Similarly, nanoparticle (NPs)-based TRAIL delivery offers novel platforms to defeat barricades to TRAIL therapeutic delivery. In the current review, we will focus on underlying mechanisms contributed to inducing resistance to TRAIL in tumor cells, and also discuss recent findings concerning the therapeutic efficacy of combined treatment of TRAIL with other antitumor compounds, and also TRAIL-delivery using human MSCs and NPs to overcome tumor cells resistance to TRAIL.
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Affiliation(s)
- Ehsan Razeghian
- Human Genetics Division, Medical Biotechnology Department, National Institute of Genetics Engineering and Biotechnology (NIGEB), Tehran, Iran
| | - Wanich Suksatan
- Faculty of Nursing, HRH Princess Chulabhorn College of Medical Science, Chulabhorn Royal Academy, Bangkok, Thailand
| | - Heshu Sulaiman Rahman
- Department of Physiology, College of Medicine, University of Suleimanyah, Suleimanyah, Iraq
- Department of Medical Laboratory Sciences, Komar University of Science and Technology, Sulaimaniyah, Iraq
| | - Dmitry O. Bokov
- Institute of Pharmacy, Sechenov First Moscow State Medical University, Moscow, Russia
- Laboratory of Food Chemistry, Federal Research Center of Nutrition, Biotechnology and Food Safety, Moscow, Russia
| | - Walid Kamal Abdelbasset
- Department of Health and Rehabilitation Sciences, College of Applied Medical Sciences, Prince Sattam bin Abdulaziz University, Al Kharj, Saudi Arabia
- Department of Physical Therapy, Kasr Al-Aini Hospital, Cairo University, Giza, Egypt
| | - Ali Hassanzadeh
- Department of Applied Cell Sciences, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran, Iran
| | - Faroogh Marofi
- Immunology Research Center (IRC), Tabriz University of Medical Sciences, Tabriz, Iran
| | - Mahboubeh Yazdanifar
- Stem Cell Transplantation and Regenerative Medicine, Department of Pediatrics, Stanford University School of Medicine, Palo Alto, CA, United States
| | - Mostafa Jarahian
- Toxicology and Chemotherapy Unit (G401), German Cancer Research Center, Heidelberg, Germany
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Paul T, Roy R, Sarkar RD, Sinha S, Biswas N. H 2O 2 mediated FLIP and XIAP down-regulation involves increased ITCH expression and ERK-Akt crosstalk in imatinib resistant Chronic Myeloid Leukemia cell line K562. Free Radic Biol Med 2021; 166:265-276. [PMID: 33631302 DOI: 10.1016/j.freeradbiomed.2021.02.024] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Revised: 01/29/2021] [Accepted: 02/13/2021] [Indexed: 11/19/2022]
Abstract
Regulation of anti-apoptotic protein FLICE-like inhibitory protein (FLIP) and X-linked inhibitor of apoptosis protein (XIAP) remains a crucial step in the cell fate determination and thus targeting these anti-apoptotic proteins could be a viable strategy for the treatment of cancer. However the regulation of FLIP and XIAP is not very well established till date. Here we have shown that ROS decreased XIAP and FLIP by activation of ubiquitin-proteasomal pathway in imatinib resistant K562 cells. Activation of the components of MAPK pathway, ERK and JNK, played a crucial role in XIAP and FLIP degradation because ectopic expression or knock down of ERK and JNK changed the pattern of ROS mediated down-regulation of these two proteins. We have also found that JNK and ERK differentially regulates FLIP and XIAP, respectively. Moreover, our data suggests that activated ERK decreased Akt phosphorylation and thus its binding to and stabilization of XIAP. On the other hand, JNK activation increased E3 ubiquitin ligase ITCH expression and its binding to FLIP which leads to its degradation. Thus, we have, for the first time elucidated that ROS mediated ERK-Akt crosstalk regulates XIAP. We have also shown for the first time that ROS regulates ITCH expression which controls FLIP degradation.
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Affiliation(s)
- Tamalika Paul
- Department of Life Sciences, Presidency University, Kolkata, India
| | - Rajdeep Roy
- Department of Life Sciences, Presidency University, Kolkata, India
| | - Rupak Dey Sarkar
- Department of Life Sciences, Presidency University, Kolkata, India
| | - Samraj Sinha
- Department of Life Sciences, Presidency University, Kolkata, India
| | - Nabendu Biswas
- Department of Life Sciences, Presidency University, Kolkata, India.
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Pereira AG, Fraga-Corral M, Garcia-Oliveira P, Lourenço-Lopes C, Carpena M, Prieto MA, Simal-Gandara J. The Use of Invasive Algae Species as a Source of Secondary Metabolites and Biological Activities: Spain as Case-Study. Mar Drugs 2021; 19:178. [PMID: 33805184 PMCID: PMC8064379 DOI: 10.3390/md19040178] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2021] [Revised: 03/18/2021] [Accepted: 03/22/2021] [Indexed: 12/23/2022] Open
Abstract
In the recent decades, algae have proven to be a source of different bioactive compounds with biological activities, which has increased the potential application of these organisms in food, cosmetic, pharmaceutical, animal feed, and other industrial sectors. On the other hand, there is a growing interest in developing effective strategies for control and/or eradication of invasive algae since they have a negative impact on marine ecosystems and in the economy of the affected zones. However, the application of control measures is usually time and resource-consuming and not profitable. Considering this context, the valorization of invasive algae species as a source of bioactive compounds for industrial applications could be a suitable strategy to reduce their population, obtaining both environmental and economic benefits. To carry out this practice, it is necessary to evaluate the chemical and the nutritional composition of the algae as well as the most efficient methods of extracting the compounds of interest. In the case of northwest Spain, five algae species are considered invasive: Asparagopsis armata, Codium fragile, Gracilaria vermiculophylla, Sargassum muticum, and Grateulopia turuturu. This review presents a brief description of their main bioactive compounds, biological activities, and extraction systems employed for their recovery. In addition, evidence of their beneficial properties and the possibility of use them as supplement in diets of aquaculture animals was collected to illustrate one of their possible applications.
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Affiliation(s)
- Antia G. Pereira
- Nutrition and Bromatology Group, Department of Analytical and Food Chemistry, Faculty of Food Science and Technology, University of Vigo, Ourense Campus, E32004 Ourense, Spain; (A.G.P.); (M.F.-C.); (P.G.-O.); (C.L.-L.); (M.C.)
- Centro de Investigação de Montanha (CIMO), Instituto Politécnico de Bragança, Campus de Santa Apolonia, 5300-253 Bragança, Portugal
| | - Maria Fraga-Corral
- Nutrition and Bromatology Group, Department of Analytical and Food Chemistry, Faculty of Food Science and Technology, University of Vigo, Ourense Campus, E32004 Ourense, Spain; (A.G.P.); (M.F.-C.); (P.G.-O.); (C.L.-L.); (M.C.)
- Centro de Investigação de Montanha (CIMO), Instituto Politécnico de Bragança, Campus de Santa Apolonia, 5300-253 Bragança, Portugal
| | - Paula Garcia-Oliveira
- Nutrition and Bromatology Group, Department of Analytical and Food Chemistry, Faculty of Food Science and Technology, University of Vigo, Ourense Campus, E32004 Ourense, Spain; (A.G.P.); (M.F.-C.); (P.G.-O.); (C.L.-L.); (M.C.)
- Centro de Investigação de Montanha (CIMO), Instituto Politécnico de Bragança, Campus de Santa Apolonia, 5300-253 Bragança, Portugal
| | - Catarina Lourenço-Lopes
- Nutrition and Bromatology Group, Department of Analytical and Food Chemistry, Faculty of Food Science and Technology, University of Vigo, Ourense Campus, E32004 Ourense, Spain; (A.G.P.); (M.F.-C.); (P.G.-O.); (C.L.-L.); (M.C.)
| | - Maria Carpena
- Nutrition and Bromatology Group, Department of Analytical and Food Chemistry, Faculty of Food Science and Technology, University of Vigo, Ourense Campus, E32004 Ourense, Spain; (A.G.P.); (M.F.-C.); (P.G.-O.); (C.L.-L.); (M.C.)
| | - Miguel A. Prieto
- Nutrition and Bromatology Group, Department of Analytical and Food Chemistry, Faculty of Food Science and Technology, University of Vigo, Ourense Campus, E32004 Ourense, Spain; (A.G.P.); (M.F.-C.); (P.G.-O.); (C.L.-L.); (M.C.)
- Centro de Investigação de Montanha (CIMO), Instituto Politécnico de Bragança, Campus de Santa Apolonia, 5300-253 Bragança, Portugal
| | - Jesus Simal-Gandara
- Nutrition and Bromatology Group, Department of Analytical and Food Chemistry, Faculty of Food Science and Technology, University of Vigo, Ourense Campus, E32004 Ourense, Spain; (A.G.P.); (M.F.-C.); (P.G.-O.); (C.L.-L.); (M.C.)
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Naimi A, Safaei S, Entezari A, Solali S, Hassanzadeh A. Knockdown of Enhancer of Zeste Homolog 2 Affects mRNA Expression of Genes Involved in the Induction of Resistance to Apoptosis in MOLT-4 Cells. Anticancer Agents Med Chem 2021; 20:571-579. [PMID: 32000648 DOI: 10.2174/1871520620666200130091955] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Revised: 11/06/2019] [Accepted: 12/05/2019] [Indexed: 12/21/2022]
Abstract
BACKGROUND The Enhancer of Zeste Homolog 2 (EZH2) is a subunit of the polycomb repressive complex 2 that silences the gene transcription via H3K27me3. Previous studies have shown that EZH2 has an important role in the induction of the resistance against the Tumor necrosis factor-Related Apoptosis-Inducing Ligand (TRAIL)-Induced Apoptosis (TIA) in some leukemia cells. OBJECTIVE The aim of this study was to determine the effect of silencing EZH2 gene expression using RNA interference on the expression of death receptors 4 and 5 (DR4/5), Preferentially expressed Antigen in Melanoma (PRAME), and TRAIL human lymphoid leukemia MOLT-4 cells. METHODS Quantitative RT-PCR was used to detect the EZH2 expression and other candidate genes following the siRNA knockdown in MOLT-4 cells. The toxicity of the EZH2 siRNA was evaluated using Annexin V/PI assay following the transfection of the cells by 80 pM EZH2 siRNA at 48 hours. RESULTS Based on the flow-cytometry results, the EZH2 siRNA had no toxic effects on MOLT-4 cells. Also, the EZH2 inhibition increased the expression of DR4/5 but reduced the PRAME gene expression at the mRNA levels. Moreover, the EZH2 silencing could not change the TRAIL mRNA in the transfected cells. CONCLUSION Our results revealed that the down-regulation of EZH2 in MOLT-4 cells was able to affect the expression of important genes involved in the induction of resistance against TIA. Hence, we suggest that the silencing of EZH2 using RNA interference can be an effective and safe approach to help defeat the MOLT-4 cell resistance against TIA.
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Affiliation(s)
- Adel Naimi
- Cellular and Molecular Research Center, Sabzevar University of Medical Science, Sabzevar, Iran.,Department of Medical Laboratory Sciences, Faculty of Paramedicine, Sabzevar University of Medical Sciences, Sabzevar, Iran
| | - Sahar Safaei
- Immunology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Atefeh Entezari
- Department of Medical Genetics, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Saeed Solali
- Department of Immunology, Division of Hematology, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Ali Hassanzadeh
- Department of Immunology, Division of Hematology, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
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Human Peripheral Blood Dendritic Cell and T Cell Activation by Codium fragile Polysaccharide. Mar Drugs 2020; 18:md18110535. [PMID: 33120897 PMCID: PMC7692045 DOI: 10.3390/md18110535] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Revised: 10/11/2020] [Accepted: 10/23/2020] [Indexed: 12/11/2022] Open
Abstract
Natural polysaccharides exhibit an immunostimulatory effect with low toxicity in humans and animals. It has shown that polysaccharide extracted from Codium fragile (CFP) induces anti-cancer immunity by dendritic cell (DC) activation, while the effect of CFP has not examined in the human immune cells. In this study, we found that CFP promoted the upregulation of CD80, CD83 and CD86 and major histocompatibility complex (MHC) class I and II in human monocyte-derived dendritic cells (MDDCs). In addition, CFP induced the production of proinflammatory cytokines in MDDCs. Moreover, CFP directly induced the activation of Blood Dendritic Cell Antigen (BDCA)1+ and BDCA3+ subsets of human peripheral blood DCs (PBDCs). The CFP-stimulated BDCA1+ PBDCs further promoted activation and proliferation of syngeneic CD4 T cells. The CFP-activated BDCA3+ PBDCs activated syngeneic CD8 T cells, which produced cytotoxic mediators, namely, cytotoxic T lymphocytes. These results suggest that CFP may be a candidate molecule for enhancing immune activation in humans.
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Wang L, Oh JY, Je JG, Jayawardena TU, Kim YS, Ko JY, Fu X, Jeon YJ. Protective effects of sulfated polysaccharides isolated from the enzymatic digest of Codium fragile against hydrogen peroxide-induced oxidative stress in in vitro and in vivo models. ALGAL RES 2020. [DOI: 10.1016/j.algal.2020.101891] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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Targeting TRAIL. Bioorg Med Chem Lett 2019; 29:2527-2534. [PMID: 31383590 DOI: 10.1016/j.bmcl.2019.07.053] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Revised: 07/24/2019] [Accepted: 07/29/2019] [Indexed: 12/11/2022]
Abstract
Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), also known as Apo2L, has been investigated in the past decade for its promising anticancer activity due to its ability to selectively induce apoptosis in tumoral cells by binding to TRAIL receptors (TRAIL-R). Macromolecules such as agonistic monoclonal antibodies and recombinant TRAIL have not proven efficacious in clinical studies, therefore several small molecules acting as TRAIL-R agonists are emerging in the scientific literature. In this work we focus on systemizing these drug molecules described in the past years, in order to better understand and predict the requirements for a novel anti-tumoral therapy based on the TRAIL-R-induced apoptotic mechanism.
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Sea Cucumber ( Stichopus japonicas) F2 Enhanced TRAIL-Induced Apoptosis via XIAP Ubiquitination and ER Stress in Colorectal Cancer Cells. Nutrients 2019; 11:nu11051061. [PMID: 31083595 PMCID: PMC6567290 DOI: 10.3390/nu11051061] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2019] [Accepted: 05/08/2019] [Indexed: 01/16/2023] Open
Abstract
Natural products have shown great promise in sensitizing cells to TNF-related apoptosis-inducing ligand (TRAIL) therapy. Sea cucumber (SC) extracts possess antitumor activity, and hence their potential to sensitize colorectal cancer (CRC) cells to TRAIL therapy was evaluated. This study used Western blotting to evaluate the combination effects of SC and TRAIL in CRC, and determined the molecular mechanism underlying these effects. SC fractions and TRAIL alone did not affect apoptosis; however, combined treatment dramatically induced the apoptosis of CRC cells, but not of normal colon cells. Combined treatment induced the expression of apoptotic proteins (poly (ADP-ribose) polymerase (PARP), caspase 3, and 8), and this effect was markedly inhibited by the ubiquitination of X-linked inhibitor of apoptosis protein (XIAP). SC did not affect the mRNA levels, but it increased proteasomal degradation and ubiquitination of the XIAP protein. Furthermore, SC induced reactive oxygen species (ROS) production, thereby activating c-Jun N-terminal kinase (JNK) and endoplasmic reticulum (ER) stress-related apoptotic pathways in CRC. Altogether, our results demonstrate that the SC F2 fraction may sensitize CRC cells to TRAIL-induced apoptosis through XIAP ubiquitination and ER stress.
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