EpCAM-targeted liposomal si-RNA delivery for treatment of epithelial cancer

Recent Advancements in the Design of Nanodelivery Systems of siRNA for Cancer Therapy

RNA interference (RNAi) has increased the possibility of restoring RNA drug targets for cancer treatment. Small interfering RNA (siRNA) is a promising therapeutic RNAi tool that targets the defective gene by inhibiting its mRNA expression and stopping its translation. However, siRNAs have flaws like poor intracellular trafficking, RNase degradation, rapid kidney filtration, off-targeting, and toxicity, which limit their therapeutic efficiency. Nanocarriers (NCs) have been designed to overcome such flaws and increase antitumor activity. Combining siRNA and anticancer drugs can give synergistic effects in cancer cells, making them a significant gene-modification tool in cancer therapy. Our discussion of NCs-mediated siRNA delivery in this review includes their mechanism, limitations, and advantages in comparison with naked siRNA delivery. We will also discuss organic NCs (polymers and lipids) and inorganic NCs (quantum dots, carbon nanotubes, and gold) that have been reported for extensive delivery of therapeutic siRNA to tumor sites. Finally, we will conclude by discussing the studies based on organic and inorganic NCs-mediated siRNA drug delivery systems conducted in the years 2020 and 2021.

Nanotechnology in the diagnosis and treatment of stroke

Increasing developments in the field of nanotechnology have ignited its use in stroke diagnosis and treatment. The benefits of structural modification, ease of synthesis, and biocompatibility support the use of nanomaterials in the clinic. The pathophysiology of stroke is complex, involving different brain regions; hence, therapeutic agents are required to be delivered to specific regions. Nanoparticles (NPs) can be engineered to help improve the delivery and release of therapeutic agents in a localized manner, especially in the penumbra. This contributes not only to therapy, but also to neurosurgery and neuroimaging. Nanomaterials also offer high efficacy with few adverse effects. In this review, we provide a concise summary of the caveats associated with nanotechnology with respect to stroke therapy and diagnosis.

Anti-epithelial cell adhesion molecule RNA aptamer-conjugated liposomal doxorubicin as an efficient targeted therapy in mice bearing colon carcinoma tumor model

To overcome the lack of selectivity and nonspecific biodistribution of drugs in the body, targeted delivery of chemotherapeutic agents with aptamers is a very effective method. In this strategy, aptamers could be specifically identified and attach to targeted molecules on the cancerous cells and deliver the chemotherapeutic agents to desired tissue with minimal or no damage to the normal cells. In this study, we designed anti-epithelial cell adhesion molecule (EpCAM) RNA aptamer conjugated PEGylated liposomal doxorubicin (ER-lip) to investigate its in vitro and in vivo anticancer abilities. Data showed that EpCAM aptamer was able to enhance cell uptake and cytotoxic effects of Dox in C26 cell line. The biodistribution study indicated that ER-lip enhanced the tumor accumulation of Dox compared to Caelyx. Also, double staining of isolated tumor cells with anti-CD44-PE-cy5 and anti-EpCAM Cy-7 antibodies indicated that tumor cells expressed a high level of EpCAM⁺ CD44⁺ cells (p ≤ .001) compared to cultured C26 cell line. in vivo results showed that ER-lip promoted survival and reduced tumor growth rate in animal model compared to Caelyx. In conclusion, these results suggested that the ER-lip could be served as promising formulation for the treatment of cancers with the high expression of EpCAM.

Emerging paradigms in treating cerebral infarction with nanotheranostics: opportunities and clinical challenges

Interest is increasing in the use of nanotheranostics as diagnosis, imaging and therapeutic tools for stroke management, but movement to the clinic remains challenging.

In-vivo assessment of the osteo-protective effects of eugenol in alveolar bone tissues

Estrogen deficiency following menopausal provokes alveolar bone loss, remodeling and inflammation. Eugenol is a phenolic compound with wide dental applications and anti-inflammatory properties. In the present study, the potential protective role of eugenol against alveolar bone deformities was investigated in an ovariectomized (OVX) rodent model. Two doses of eugenol (2.5 and 5 mg/kg/d) were administered to OVX animals for 12 weeks. In Serum, markers of bone metabolism and pro-inflammatory cytokines were estimated using ELISA. Alveolar bone morphometry was analyzed using high-resolution micro-computed tomography (CT). Bone histological analysis (H&E stain) was also performed. Alveolar bone expression of osteoclastogenesis modulating factors, such as osteoprotegerin (OPG), receptor activator of nuclear factor kappa-b ligand (RANKL) and inflammatory mediators, were measured using immunohistochemistry. Eugenol failed to correct elevated body weights and uterine atrophy in OVX rats. The significant elevation of bone metabolic markers and inflammatory cytokines in OVX animals were markedly improved by eugenol treatment, particularly the higher dose. Eugenol treatment considerably attenuated morphometric trabecular alterations of the alveolar bone and improved alveolar resorption and gingival infiltration. Alveolar bone of OVX animals showed augmented expression of RANKL, OPG and inflammatory cytokines, which were corrected by eugenol treatment. Alveolar bone loss and remodeling associated with estrogen insufficiency was ameliorated by eugenol owing to its anti-inflammatory properties, suggesting an extra dental impact for eugenol.

'Nano-in-nano' hybrid liposomes increase target specificity and gene silencing efficiency in breast cancer induced SCID mice

Gene silencing has immense potential in the treatment of cancer. However, enhancement of its efficiency requires the development of specifically targeted and safe carrier systems. Cationic carriers are generally limited by their immunogenicity. Hence, in this study, we report hybrid liposomes encapsulating Poly (L-lysine)-siRNA complex to silence epithelial cell adhesion molecule (EpCAM), highly expressed in epithelial cancers. The hybrid liposomes LL1 (Egg PC:DSPE-PEG, 10:0) and hybrid immunoliposomes LL2 (Egg PC:DSPE-PEG, 8:2) linked with EpCAM antibody as the targeting ligand showed an encapsulation efficiency of 70% and 86%, respectively. LL2 liposomes with a zeta potential of -26mV exhibited good colloidal stability in phosphate buffered saline containing bovine serum albumin and fetal bovine serum at 37°C. Cell uptake studies showed increased uptake of the LL2 when compared to LL1 liposomes. Finally, the hybrid immunoliposomes were evaluated for their efficacy in regressing the tumor volume in SCID mice. Eight doses each of 0.15mg/kg, which is among the lowest reported siRNA concentrations, were administered to the animals. About 45% reduction in tumor volume was achieved after 28days in the mice treated with LL2 when compared with the positive control and LL1 treated groups. Thus, our results demonstrate that the 'nano-in-nano' concept of encapsulating poly (l-Lysine) complexed EpCAM siRNA in immunoliposomes may be a promising strategy to treat EpCAM-positive epithelial cancers, especially as an adjuvant therapy.