China 
Africa 
Explore chapters and articles related to this topic
Nanoparticle-Mediated Small RNA Deliveries for Molecular Therapies
Published in D. Sakthi Kumar, Aswathy Ravindran Girija, Bionanotechnology in Cancer, 2023
Ramasamy Paulmurugan, Uday Kumar Sukumar, Tarik F. Massoud
The miRNAs are small, highly conserved, non-coding RNAs of 18–24 nucleotides in length endogenously expressed in cells that are engaged in the post transcriptional regulation of gene expression through the RNAi pathway [16, 89, 91–94, 113–118]. The miRNA expression is dysregulated in cellular diseases including cancer, where miRNA expressions are closely associated with cancer development, growth, invasion, and metastasis [16, 89, 91–94, 113–118]. Based on their functions, they are categorized as oncogenic miRNAs (oncomiRs) and tumor suppressor miRNAs. OncomiRs promote tumor growth by inhibiting tumor suppressor and apoptotic genes, whereas anti-oncomiRs block the function of proteins involved in cell cycle and apoptosis [93, 116]. There are numerous miRNAs that are reported to be tumor suppressors (miR-17-5p, miR-21, miR-29, miR-34, miR-127, miR-155, let-7, etc.) [115]. This list has been growing, and it is expected that there may be many more miRNAs with important functions yet to be discovered. Recently, we and several other groups have been investigating miRNAs as a new class of molecularly targeted anticancer therapeutics [4, 5].
RNA Nanotechnology and Extracellular Vesicles (EVs) for Gene Therapy
Published in Peixuan Guo, Kirill A. Afonin, RNA Nanotechnology and Therapeutics, 2022
Zhefeng Li, Fengmei Pi, Peixuan Guo
Despite the challenge in efficient delivery, RNA interference (RNAi) holds great potential for therapeutic applications by specific gene suppression (Whitehead et al., 2009), (Zhang et al., 2013a). During the last few decades, major efforts had been spent on achieving efficient in vivo delivery of siRNA (Whitehead et al., 2009) or miRNA (Zhang et al., 2013b) to target cell using different strategies, including the recent approval of Onpattro (patisiran), the first-ever RNAi therapeutic using a lipid nanoparticle platform (Garber, 2018). Delivery strategies including cationic lipids (Semple et al., 2010), cationic liposomes (Reddy et al., 2002), and cationic polymers (Li et al., 2018b) that can deliver the RNAi to cells but specific targeting is still challenging. The attempted approaches for specific targeting includes the use of peptide (Ben et al., 2018), antibody (Toloue & Ford, 2011), chemical ligands (Teo et al., 2015), and RNA aptamers (Chu et al., 2006), etc. Polymers (Priegue et al., 2016), gold nanoparticles (Guo et al., 2010), RNA nanoparticles (Shu et al., 2011a; Shu et al., 2015; Binzel et al., 2016; Guo et al., 2018), and liposomes (Yang et al., 2011) have been used as delivery vesicles (Dong et al., 2019). However, it remains challenging to make the siRNA interference functional after delivery into the cells via folate receptor, mainly due to the difficulty in endosomal escape.
Clinical Applications of siRNA
Published in Yashwant V. Pathak, Gene Delivery Systems, 2022
Seth Kwabena Amponsah, Ismaila Adams, Kwasi Agyei Bugyei
Colorectal cancer is a common digestive system malignancy (34). Surgery, radiation and chemotherapeutic interventions are unable to increase survival among patients with colorectal cancer beyond five years (35). Given that colonic epithelial cells undergo neoplastic transformation, RNAi has been recommended as a treatment approach. RNAi offers greater efficacy and reduced toxicity. However, due to transfection, limited specificity, low immune response and superfluous gene insertion, only a handful of RNAi-based treatments have undergone clinical trials (28). New molecular targets for RNAi are still being studied (36). Novel intracellular targeting technologies, such as siRNA, and new nano-delivery systems have been reported to have high anticancer potential and few side effects (37). Furthermore, colon cancer causes carcinogenesis via a number of molecular mechanisms, including overexpression of EGFR (38). Dimerized EGFR is known to deliver mitotic signals to tumor cells, causing cell proliferation and resistance to apoptosis. As a result, siRNA knockout of EGFR has been proposed as a plausible treatment option for colon cancer (39).
Synthesis of PEGylated cationic curdlan derivatives with enhanced biocompatibility
Published in Journal of Biomaterials Science, Polymer Edition, 2022
Muqier Muqier, Hai Xiao, Xiang Yu, Yifeng Li, Mingming Bao, Qingming Bao, Shuqin Han, Huricha Baigude
RNA interference (RNAi) is a natural cellular process that silences gene expression by degrading target messenger RNA (mRNA) through the efficient and specific recognition of complementary sequences with double stranded RNA (dsRNA) [1–4]. Small interfering RNAs (siRNAs) are noncoding RNAs consisting of 20–23 nucleotides with complete complementarity to the target mRNA [5, 6]. The therapeutic potential of siRNA has been proven in the clinical treatment of various diseases [7], including hereditary transthyretin-mediated amyloidosis [8], acute hepatic porphyria [9] and primary hyperoxaluria type 1 [10]. Despite such tremendous progress at the clinical level, siRNA therapies still face several challenges due to the intrinsic immunogenicity and nuclease susceptibility of RNA molecules [11–13].
Applications and hazards associated with carbon nanotubes in biomedical sciences
Published in Inorganic and Nano-Metal Chemistry, 2020
Ali Hassan, Afraz Saeed, Samia Afzal, Muhammad Shahid, Iram Amin, Muhammad Idrees
Small interfering RNA(RNAi) is a process of gene silencing at co-transcriptional level triggered by micro RNA and small interfering RNA.[65] Due to gene silencing ability, RNAi has applications in gene therapy. Small RNA encoding extracellular signal-regulated kinase was delivered to cardiomyocyte cells by using functional SWCNTs. The result obtained with approximately 75% knockdown of extracellular signal-regulated kinase target protein.[66] In chemically functionalized CNTs, negatively charge small RNA condense successfully with the amino group of CNTs. This reduces the need for linker molecules and transports small RNA inside the cell efficiently which then down-regulate the expression of target gene significantly.[67]
Intracellular controlled release prolongs the time period of siRNA-based gene suppression
Published in Journal of Biomaterials Science, Polymer Edition, 2021
Kazuki Chujo, Jun-ichiro Jo, Yasuhiko Tabata
RNA interference (RNAi) is a gene silencing process by inhibiting target messenger RNA (mRNA) in the sequence-specific manner in the cell cytoplasm. The RNAi was initially discovered by Fire et al. in 1998 [1]. Small interfering RNA (siRNA) is a synthetic double-stranded RNA (dsRNA) of 21–23 base pairs. SiRNA binds to the RNA-induced silencing complex (RISC) in the cell cytoplasm, and then recognizes and cleaves the target mRNA [2, 3]. This RNAi is useful for in the research field of basic cell biology and has extensively utilized to investigate the mechanism of cell functions. In addition, the technology of specific gene suppression is also a promising tool to regulate the cell functions, which plays an important role in regenerative medicine. The regenerative medicine is one of the research fields to control the cell functions aiming at cell-based therapy. However, generally siRNA is not always internalized into cells in the native state. The siRNA-induced suppression of gene expression is not achieved efficiently. As one trial to tackle the issue, it is necessary to develop the vectors to deliver siRNA to the interior of cells. There are some problems to be improved, such as the low efficiency of cellular internalization and the short time period of gene expression suppression [4]. Several viral [5–7] and non-viral vectors [8–10] have been investigated to improve the efficacy of gene expression. In addition, for the viral vectors have issues to be resolved, such as the immunogenicity and cytotoxicity. On the other hand, as the non-viral vectors, cationic liposomes [11–13], micelles [14, 15], nanospheres [16, 17] and gold nanospheres [18, 19] have been extensively investigated. However, the transfection efficiency is low compared with that of viral vectors and the time period of gene expression suppression is short.