Chitosan nanoparticle-delivered siRNA reduces CXCR4 expression and sensitizes breast cancer cells to cisplatin

Effects of CD44 siRNA on inhibition, survival, and apoptosis of breast cancer cell lines (MDA-MB-231 and 4T1)

BACKGROUND

Breast cancer (BC) is one of the most common cancers in the world. Despite the many advances that have been made in treating patients, many patients are still resistant to treatment. CD44 is one of the surface glycoproteins of BC cells that plays an important role in the proliferation of these cells and inhibition of their apoptosis. Therefore, targeting it can be a treatment way for BC patients.

METHODS

In this study, the effect of anti-CD44 siRNA on the proliferation, apoptosis, and migration rate of MDA-MB-231 and 4T1 cells was investigated. The techniques used in this study were MTT assay, RT-PCR, and flow cytometry.

RESULTS

The apoptosis and proliferation rates in CD44 siRNA-treated cells were higher and lower, respectively, compared to untreated cells. Also, cell migration was less in treated cells compared to untreated cells. CD44 siRNA also decreased the expression of CXCR4, c-myc, Vimentin, ROCK, and MMP-9.

CONCLUSION

Finally, CD44 targeting can be a good treatment option to make BC cells more sensitive to apoptosis.

Chitosan nanocarriers for non-coding RNA therapeutics: A review

Non-coding RNA (ncRNA)-based therapies entail delivering ncRNAs to cells to regulate gene expression and produce proteins that combat infections, cancer, neurological diseases, and bone abnormalities. Nevertheless, the therapeutic potential of these ncRNAs has been limited due to the difficulties in delivering them to specific cellular targets within the body. Chitosan (CS), a biocompatible cationic polymer, interacts with negatively charged RNA molecules to form stable complexes. It is a promising biomaterial to develop nanocarriers for ncRNA delivery, overcoming several disadvantages of traditional delivery systems. CS-based nanocarriers can protect ncRNAs from degradation and target-specific delivery by surface modifications and intracellular release profiles over an extended period. This review briefly summarizes the recent developments in CS nanocarriers' synthesis and design considerations and their applications in ncRNA therapeutics for treating various diseases. We also discuss the challenges and limitations of CS-based nanocarriers for ncRNA therapeutics and potential strategies for overcoming these challenges.

Chitosan-functionalized bioplatforms and hydrogels in breast cancer: immunotherapy, phototherapy and clinical perspectives

Breast cancer is the most common and malignant tumor among women. Chitosan (CS)-based nanoparticles have been introduced into breast cancer therapy as a way to increase the targeted delivery of drugs and genes to the tumor site. CS nanostructures suppress tumorigenesis by enhancing both the targeted delivery of cargo (drug and gene) and its accumulation in tumor cells. The tumor cells internalize CS-based nanoparticles through endocytosis. Moreover, chitosan nanocarriers can also induce phototherapy-mediated tumor ablation. Smart and multifunctional types of CS nanoparticles, including pH-, light- and redox-responsive nanoparticles, can be used to improve the potential for breast cancer removal. In addition, the acceleration of immunotherapy by CS nanoparticles has also been achieved, and there is potential to develop CS-nanoparticle hydrogels that can be used to suppress tumorigenesis.

siRNA and targeted delivery systems in breast cancer therapy

Recently, nucleic acid drugs have been considered as promising candidates in treatment of various diseases, especially cancer. Because of developing resistance to conventional chemotherapy, use of genetic tools in cancer therapy appears inevitable. siRNA is a RNAi tool with capacity of suppressing target gene. Owing to overexpression of oncogenic factors in cancer, siRNA can be used for suppressing those pathways. This review emphasizes the function of siRNA in treatment of breast tumor. The anti-apoptotic-related genes including Bcl-2, Bcl-xL and survivin can be down-regulated by siRNA in triggering cell death in breast cancer. STAT3, STAT8, Notch1, E2F3 and NF-κB are among the factors with overexpression in breast cancer that their silencing by siRNA paves the way for impairing tumor proliferation and invasion. The oncogenic mechanisms in drug resistance development in breast tumor such as lncRNAs can be suppressed by siRNA. Furthermore, siRNA reducing P-gp activity can increase drug internalization in tumor cells. Because of siRNA degradation at bloodstream and low accumulation at tumor site, nanoplatforms have been employed for siRNA delivery to suppress breast tumor progression via improving siRNA efficacy in gene silencing. Development of biocompatible and efficient nanostructures for siRNA delivery can make milestone progress in alleviation of breast cancer patients.

Surface Design Options in Polymer- and Lipid-Based siRNA Nanoparticles Using Antibodies

The mechanism of RNA interference (RNAi) could represent a breakthrough in the therapy of all diseases that arise from a gene defect or require the inhibition of a specific gene expression. In particular, small interfering RNA (siRNA) offers an attractive opportunity to achieve a new milestone in the therapy of human diseases. The limitations of siRNA, such as poor stability, inefficient cell uptake, and undesired immune activation, as well as the inability to specifically reach the target tissue in the body, can be overcome by further developments in the field of nanoparticulate drug delivery. Therefore, types of surface modified siRNA nanoparticles are presented and illustrate how a more efficient and safer distribution of siRNA at the target site is possible by modifying the surface properties of nanoparticles with antibodies. However, the development of such efficient and safe delivery strategies is currently still a major challenge. In consideration of that, this review article aims to demonstrate the function and targeted delivery of siRNA nanoparticles, focusing on the surface modification via antibodies, various lipid- and polymer-components, and the therapeutic effects of these delivery systems.

A Poly-Chitosan and Cis-Platinum Conjugated Composite Nanoparticle System for Liver Cancer Therapy

The aim of this study was to test an effective nano-pole capsule loaded cis-platinum (CP) transplantation device for liver cancer (LC) therapy. A novel nano-pole capsule was designed as a new vector for storing CP. HepG2 cells and a B6/J mouse model were used to test the efficiency of polyethyleneimine-cis-platinum (PEI-CP) and poly-chitosan-cis-platinum (PC-CP). Infiltration efficiency and transplantation efficiency tests were performed to study the performance of the delivery system, and fibroblast reactions and macrophage numbers were observed, to test for immune rejection and foreign body reactions. The apoptosis rate and tumor diameter of hepatocellular carcinoma cells were used to evaluate the effect of the tumor therapy. We also studied the functional mechanism of different CP delivery systems. The infiltration and transplantation efficiencies of PC-CP were higher than that of PEI-CP; Less foreign body reaction appeared in PC system, with less fibroblast reaction and lower macrophage reaction. The clinical efficacy of PC-CP in terms of tumor apoptosis and diameter reduction was superior to that of PEI-CP. We demonstrated that PC-CP had a more significant alteration effect on mTOR, P-Ak, LC3 and P53. The PC system can better deliver and release drugs than PEI-CP, and may be a better choice for LC therapy in the future.

Pretreatment with licochalcone a enhances therapeutic activity of rat bone marrow mesenchymal stem cells in animal models of colitis

OBJECTIVES

Colitis has a high prevalence rate, limited treatment options, and needs to be solved urgently. Application of Licochacone A (LA) or rBMMSCs alone in the treatment of colitis has a certain but limited effect. This study aims to develop an LA-based strategy to improve mesenchymal stem cells' (MSCs') therapeutic capacity in mice DSS-induced colitis by increasing the number of MSCs migrating to the inflammation site.

MATERIALS AND METHODS

In vivo, we injected MSCs pretreated with LA, MSCs alone, or PBS into the tail vein of colitis mice, and assessed the colon length, disease activity index (DAI) score, body weight, HAI score, and tracked the location of MSCs at day 10. In vitro, we knocked down the CXCR4 gene by siRNA and then treated it with LA, then tested the mRNA level of CXCR4 and the migration ability of group CXCR4, CXCR4+LA, LA, and control to verify the relationship between this effect and the SDF-1-CXCR4 signaling pathway.

RESULTS

The mice that received LA- pretreated MSCs had ameliorated body weight loss, preserved colon morphology, and decreased DAI and histological activity index (HAI) compared with the MSCs group. Besides, the number of MSCs migrating to the inflammation site significantly increased in group LA+MSCs, and expression of CXCR4 significantly increased too. Furthermore, we found that LA could partly revise the decrease of the migration of MSCs and the expression of CXCR4 mRNA caused by CXCR4-siRNA.

CONCLUSION

LA may improve the migration ability of MSCs through increasing CXCR4 expression therapy enhancing their therapeutic activity.

NEAT1 siRNA Packed with Chitosan Nanoparticles Regulates the Development of Colon Cancer Cells via lncRNA NEAT1/miR-377-3p Axis

This study was for verifying that transfecting colon cancer cells (CCCs) with lncRNA NEAT1 packed with siRNA chitosan nanoparticles (CNPs) can suppress lncRNA NEAT1 and biological behaviors of the cells. siRNA targeting lncRNA NEAT1 expression vector was constructed and then transfected into CCCs after being packed with CNPs. Subsequently, the impact of the transfection on biological behaviors of the cells was evaluated. As a result, with high expression in CCCs, NEAT1 was negatively bound up with miR-377-3p in cases with colon cancer (CC), and dual luciferase reporter assay confirmed the potential binding region. Additionally, after downregulating NEAT1 in CCCs, transfection of NEAT1 siRNA packed with CNPs brought a great inhibition on cell proliferation and a promotion on apoptosis, and inhibiting miR-377-3p was able to offset the role of silencing NEAT1 in CCCs. Therefore, in our opinion, NEAT1 siRNA packed with CNPs can hinder the growth and metastasis of CCCs by knocking down NEAT1 in CC, and its mechanism may be achieved by targeting miR-377-3p, which offers a novel direction for treating CC.

Employing siRNA tool and its delivery platforms in suppressing cisplatin resistance: Approaching to a new era of cancer chemotherapy

Although chemotherapy is a first option in treatment of cancer patients, drug resistance has led to its failure, requiring strategies to overcome it. Cancer cells are capable of switching among molecular pathways to ensure their proliferation and metastasis, leading to their resistance to chemotherapy. The molecular pathways and mechanisms that are responsible for cancer progression and growth, can be negatively affected for providing chemosensitivity. Small interfering RNA (siRNA) is a powerful tool extensively applied in cancer therapy in both pre-clinical (in vitro and in vivo) and clinical studies because of its potential in suppressing tumor-promoting factors. As such oncogene pathways account for cisplatin (CP) resistance, their targeting by siRNA plays an important role in reversing chemoresistance. In the present review, application of siRNA for suppressing CP resistance is discussed. The first priority of using siRNA is sensitizing cancer cells to CP-mediated apoptosis via down-regulating survivin, ATG7, Bcl-2, Bcl-xl, and XIAP. The cancer stem cell properties and related molecular pathways including ID1, Oct-4 and nanog are inhibited by siRNA in CP sensitivity. Cell cycle arrest and enhanced accumulation of CP in cancer cells can be obtained using siRNA. In overcoming siRNA challenges such as off-targeting feature and degradation, carriers including nanoparticles and biological carriers have been applied. These carriers are important in enhancing cellular accumulation of siRNA, elevating gene silencing efficacy and reversing CP resistance.

Biomedical application of chitosan-based nanoscale delivery systems: Potential usefulness in siRNA delivery for cancer therapy

Gene therapy is an emerging and promising strategy in cancer therapy where small interfering RNA (siRNA) system has been deployed for down-regulation of targeted gene and subsequent inhibition in cancer progression; some issues with siRNA, however, linger namely, its off-targeting property and degradation by enzymes. Nanoparticles can be applied for the encapsulation of siRNA thus enhancing its efficacy in gene silencing where chitosan (CS), a linear alkaline polysaccharide derived from chitin, with superb properties such as biodegradability, biocompatibility, stability and solubility, can play a vital role. Herein, the potential of CS nanoparticles has been discussed for the delivery of siRNA in cancer therapy; proliferation, metastasis and chemoresistance are suppressed by siRNA-loaded CS nanoparticles, especially the usage of pH-sensitive CS nanoparticles. CS nanoparticles can provide a platform for the co-delivery of siRNA and anti-tumor agents with their enhanced stability via chemical modifications. As pre-clinical experiments are in agreement with potential of CS-based nanoparticles for siRNA delivery, and these carriers possess biocompatibiliy and are safe, further studies can focus on evaluating their utilization in cancer patients.

HER-2/neu and MYC gene silencing in breast cancer: therapeutic potential and advancement in nonviral nanocarrier systems

Globally, breast cancer is the second leading cause of cancer-related mortality among women, with approximately 1.4 million new cases diagnosed annually. Associated genetic perturbations are emerging in the face of intense scientific enquiry, facilitating its classification, prognostication and treatment. RNAi, utilizing siRNA, is a powerful treatment strategy to silence disease-causing genes. However, therapeutic siRNA instability and poor cellular uptake have limited its clinical application, necessitating the use of nanocarriers. In this review, we highlight the RNAi mechanism, HER-2/neu and MYC as breast cancer gene targets, and nonviral nanocarriers as potentially safe and efficient delivery systems.

Chitosan is a potential inhibitor of ovarian cancer: Molecular aspects

Although ovarian cancer has a lower prevalence than breast cancer, its mortality rate is three times higher, which is reported to increase in the coming years. As the early stages of ovarian cancer do not have any obvious symptoms, in most of the cases, this cancer is diagnosed at advanced stages with a poor prognosis. Moreover, in many patients who are diagnosed with advanced stage, relapse of the disease and drug resistance are observed. Over the past years, these women have been treated with chemotherapy and cytoreductive surgeries. However, the chemotherapy could affect the healthy tissues in addition to the malignancies. Therefore, discovering new diagnostic and therapeutic options seems to be a crucial need. Unlike the common invasive and/or nonspecific treatments, nanomedicine is trying to find a new way for cancer imaging, diagnosis, and drug delivery method. Nanoparticles (NPs), which has recently drawn attention, can be used in order to reduce the toxicity and frequent dosing of drugs, tumor-specific delivery, and early diagnosis for malignancies. Chitosan as an NP and product of chitin deacetylation has multiple characteristics, including biocompatibility, biodegradability, and safety. In this review, we cover the studies concerned with the role of chitosan in finding solutions to overcome the problems faced in ovarian cancer treatments. Furthermore, we highlight how chitosan is being used in delivering chemotherapy drugs, gene therapy, and imaging methods for both detection and image-guided therapies.

siRNA therapeutics for breast cancer: recent efforts in targeting metastasis, drug resistance, and immune evasion

Small interfering RNA (siRNA) has an established and precise mode of action to achieve protein knockdown. With the ability to target any protein, it is very attractive as a potential therapeutic for a plethora of diseases driven by the (over)expression of certain proteins. Utilizing siRNA to understand and treat cancer, a disease largely driven by genetic aberration, is thus actively investigated. However, the main hurdle for the clinical translation of siRNA therapeutics is to achieve effective delivery of siRNA molecules to tumors and the site of action, the cytosol, within cancer cells. Several nanoparticle delivery platforms for siRNA have been developed. In this Review, we describe recent efforts in developing siRNA therapeutics for the treatment of cancer, with particular emphasis on breast cancer. Instead of conventionally targeting proliferation and apoptosis aspects of tumorigenesis, we focus on recent attempts in targeting cancer's metastasis, drug resistance, and immune evasion, which are considered more challenging and less manageable in clinics with current therapeutic molecules. siRNA can target all proteins, including traditionally undruggable proteins, and is thus poised to address these clinical challenges. Evidence also suggests that siRNA can be superior to antibodies or small molecule inhibitors when inhibiting the same druggable pathway. In addition to cancer cells, the role of the tumor microenvironment has been increasingly appreciated. Components in the tumor microenvironment, particularly immune cells, and thus siRNA-based immunotherapy, are under extensive investigation. Lastly, multiple siRNAs with or without additional drugs can be codelivered on the same nanoparticle to the same target site of action, maximizing their potential synergy while limiting off-target toxicity.