Delivery of RGD-modified liposome as a targeted colorectal carcinoma therapy and its autophagy mechanism

Nanomaterials in crossroad of autophagy control in human cancers: Amplification of cell death mechanisms

Cancer is the result of genetic abnormalities that cause normal cells to grow into neoplastic cells. Cancer is characterized by several distinct features, such as uncontrolled cell growth, extensive spreading to other parts of the body, and the ability to resist treatment. The scientists have stressed the development of nanostructures as novel therapeutic options in suppressing cancer, in response to the emergence of resistance to standard medicines. One of the specific mechanisms with dysregulation during cancer is autophagy. Nanomaterials have the ability to specifically carry medications and genes, and they can also enhance the responsiveness of tumor cells to standard therapy while promoting drug sensitivity. The primary mechanism in this process relies on autophagosomes and their fusion with lysosomes to break down the components of the cytoplasm. While autophagy was initially described as a form of cellular demise, it has been demonstrated to play a crucial role in controlling metastasis, proliferation, and treatment resistance in human malignancies. The pharmacokinetic profile of autophagy modulators is poor, despite their development for use in cancer therapy. Consequently, nanoparticles have been developed for the purpose of delivering medications and autophagy modulators selectively and specifically to the cancer process. Furthermore, several categories of nanoparticles have demonstrated the ability to regulate autophagy, which plays a crucial role in defining the biological characteristics and response to therapy of tumor cells.

Functionalized liposomes as a potential drug delivery systems for colon cancer treatment: A systematic review

Colon cancer is one of the lethal diseases in the world with approximately 700,000 fatalities annually. Nowadays, due to the side effects of existing methods in the treatment of colon cancer such as radiotherapy and chemotherapy, the use of targeted nanocarriers in cancer treatment has received wide attention, and among them, especially liposomes have been studied a lot. Based on this, anti-tumor drugs hidden in targeted active liposomes can selectively act on cancer cells. In this systematic review, the use of various ligands such as folic acid, transferrin, aptamer, hyaluronic acid and cRGD for active targeting of liposomes to achieve improved drug delivery to colon cancer cells has been reviewed. The original articles published in English in the databases of Science Direct, PubMed and Google scholar from 2012 to 2022 were reviewed. From the total of 26,256 published articles, 19 studies met the inclusion criteria. The results of in vitro and in vivo studies have revealed that targeted liposomes lead to increasing the efficacy of anti-cancer agents on colon cancer cells with reducing side effects compared to free drugs and non-targeted liposomes. To the best of our knowledge, this is the first systematic review showing promising results for improvement treatment of colon cancer using targeted liposomes.

Preparation, in vitro anti-tumour activity and in vivo pharmacokinetics of RGD-decorated liposomes loaded with shikonin

Shikonin (SHK) has been evidenced to possess effects against various cancer cells. However, poor aqueous solubility and high toxicity restrict its application. In the study, RGD-decorated liposomes loaded with SHK (RGD-Lipo-SHK) were prepared via thin-film hydration method. Characterization and cellular uptake of liposomes was evaluated. Cytotoxicity of blank liposomes and different SHK formulations was measured against breast cancer cells (MDA-MB-231, MCF-7, and MCF-10A). Anti-tumour effects and pharmacokinetic parameters of different SHK formulations were appraised in tumour spheroids and in rat model, respectively. Liposomes displayed a particle size of less than 127 nm with a polydispersity index about 0.21. The encapsulation efficiency was about 91% for SHK, and drug leakage rate of liposomes was less than 6%. RGD-Lipo-SHK showed superior cellular internalization in the αvβ3-positive MDA-MB-231 cells. Blank liposomes had no cytotoxicity to MDA-MB-231 and MCF-7 cells. Howbeit, different SHK formulations obviously inhibited proliferation of MCF-10A cells, especially free SHK. Meanwhile, RGD-Lipo-SHK significantly inhibited growth inhibition of tumour spheroids. The pharmacokinetics study indicated that the peak concentration, area under plasma concentration-time curves, half-life, and mean residence time of RGD-Lipo-SHK distinctly increased compared with those of free SHK. Altogether, these results demonstrated RGD-Lipo-SHK could reduce cytotoxicity, strengthen the antitumor-targeted effect, and prolong circulation time, which provides a foundation for further in vivo experimentations.

Autophagy-modulating biomembrane nanostructures: A robust anticancer weapon by modulating the inner and outer cancer environment

Recently, biomembrane nanostructures, such as liposomes, cell membrane-coated nanostructures, and exosomes, have demonstrated promising anticancer therapeutic effects. These nanostructures possess remarkable biocompatibility, multifunctionality, and low toxicity. However, their therapeutic efficacy is impeded by chemoresistance and radiotherapy resistance, which are closely associated with autophagy. Modulating autophagy could enhance the therapeutic sensitivity and effectiveness of these biomembrane nanostructures by influencing the immune system and the cancer microenvironment. For instance, autophagy can regulate the immunogenic cell death of cancer cells, antigen presentation of dendritic cells, and macrophage polarization, thereby activating the inflammatory response in the cancer microenvironment. Furthermore, combining autophagy-regulating drugs or genes with biomembrane nanostructures can exploit the targeting and long-term circulation properties of these nanostructures, leading to increased drug accumulation in cancer cells. This review explores the role of autophagy in carcinogenesis, cancer progression, metastasis, cancer immune responses, and resistance to treatment. Additionally, it highlights recent research advancements in the synergistic anticancer effects achieved through autophagy regulation by biomembrane nanostructures. The review also discusses the prospects and challenges associated with the future clinical translation of these innovative treatment strategies. In summary, these findings provide valuable insights into autophagy, autophagy-modulating biomembrane-based nanostructures, and the underlying molecular mechanisms, thereby facilitating the development of promising cancer therapeutics.

MicroRNA-195 liposomes for therapy of Alzheimer's disease

The complex etiologies and mechanisms of Alzheimer's disease (AD) underscore the importance for devising multitarget drugs to achieve effective therapy. MicroRNAs (miRNAs) are capable of concurrently regulating the expression of multiple proteins by selectively targeting disease- associated genes in a sequence-specific fashion. Nonetheless, as RNA-based drugs, their stability in the circulation and capacity of traversing the blood-brain barrier (BBB) is largely compromised, thereby limiting their potential clinical applications. In this study, we formulated the nanoliposomes encapsulating polyethyleneimine (PEI)/miR-195 complex (DPMT@PEI/miR-195) that was engineered through dual modifications to contain P-aminophenyl-alpha-d-mannopyranoside (MAN) and cationic cell-penetrating peptide (TAT). DPMT@PEI/miR-195 exhibited the enhanced BBB- and cell membrane penetrating capability. As expected, we observed that DPMT@PEI/miR-195 administered through intravenous tail injection of produced greater effectiveness than donepezil and the same range of effect as aducanumab in alleviating the cognitive decline in 7-month-old APP/PS1 mice. Moreover, the combination treatment with DPMT@PEI/miR-195 and donepezil effectively ameliorated the deterioration of cognition in 16-month-old APP/PS1 mice, with enhanced effects than either DPMT@PEI/miR-195 or donepezil alone. Furthermore, DPMT@PEI/miR-195 effectively attenuated the positive signals of Aβ, AT8, and CD68 in APP/PS1 mice without notable side effects. Our findings indicate DPMT@PEI/miR-195 as a promising potentially new agent or approach for the prophylaxis and treatment of early and advanced stages of Alzheimer's disease.

Specific surface modification of liposomes for gut targeting of food bioactive agents

Liposomes have become a research hotspot in recent years as food delivery systems with attractive properties, including the bilayer structure assembled like the cell membrane, reducing the side-effect and improving environmental stability of cargos, controlling release, extending duration of functional ingredients, and high biodegradable and biocompatible abilities in the body. However, the conventional liposomes lack stability during storage and are weak in targeted absorption in the gastrointestinal track. At present, surface modification has been approved to be an effective platform to shield these barricades and help liposomes deliver the agents safely and effectively to the ideal site. In this review, the gastrointestinal stability of conventional liposomes, cargo release models from liposomes, and the biological fate of the core materials after release were emphasized. Then, the strategies in both physical and chemical perspectives to improve the stability and utilization of liposomes in the gastrointestinal tract, and the emerging approaches for improving gut targeting by specifically modified liposomes and the intestinal receptors relative to liposomes/cargos absorption were highlighted. Last but not the least, the safety, challenges, and opportunities for the improvement of liposomal bioavailability were also discussed to inspire new applications of liposomes as oral carriers.

Liposome encapsulated anticancer drugs on autophagy in cancer cells - current and future perspective

Autophagy act as a double-edged sword in cancer with both tumor promoting and inhibiting roles. Under normal conditions of autophagy, the damaged cell organelles and other debris degrade inside the lysosome to provide energy and macromolecular precursors. However, enhanced autophagy can lead to apoptosis and programmed cell death highlighting its significance in cancer therapy. Liposome-based drug delivery systems for treating cancer patients have significant advantages over their non-formulated or free drug counterparts which could be effectively used to manipulate autophagy pathway in cancer patients. In the current review, drug uptake by the cells and its role in autophagy-mediated cancer cell death are discussed. Besides, the challenges and translational difficulties associated with the use of liposome-based chemotherapeutic drugs in clinical trials and in biomedical applications are also discussed.

The Role of Integrins for Mediating Nanodrugs to Improve Performance in Tumor Diagnosis and Treatment

Integrins are heterodimeric transmembrane proteins that mediate adhesive connections between cells and their surroundings, including surrounding cells and the extracellular matrix (ECM). They modulate tissue mechanics and regulate intracellular signaling, including cell generation, survival, proliferation, and differentiation, and the up-regulation of integrins in tumor cells has been confirmed to be associated with tumor development, invasion, angiogenesis, metastasis, and therapeutic resistance. Thus, integrins are expected to be an effective target to improve the efficacy of tumor therapy. A variety of integrin-targeting nanodrugs have been developed to improve the distribution and penetration of drugs in tumors, thereby, improving the efficiency of clinical tumor diagnosis and treatment. Herein, we focus on these innovative drug delivery systems and reveal the improved efficacy of integrin-targeting methods in tumor therapy, hoping to provide prospective guidance for the diagnosis and treatment of integrin-targeting tumors.

Antimicrobial peptides CS-piscidin-induced cell death involves activation of RIPK1/PARP, and modification with myristic acid enhances its stability and tumor-targeting capability

Ovarian cancer (OC) is a highly lethal gynecological malignancy, often diagnosed at advanced stages with limited treatment options. Here, we demonstrate that the antimicrobial peptide CS-piscidin significantly inhibits OC cell proliferation, colony formation, and induces cell death. Mechanistically, CS-piscidin causes cell necrosis by compromising the cell membrane. Furthermore, CS-piscidin can activate Receptor-interacting protein kinase 1 (RIPK1) and induce cell apoptosis by cleavage of PARP. To improve tumor targeting ability, we modified CS-piscidin by adding a short cyclic peptide, cyclo-RGDfk, to the C-terminus (CS-RGD) and a myristate to the N-terminus (Myr-CS-RGD). Our results show that while CS-RGD exhibits stronger anti-cancer activity than CS-piscidin, it also causes increased cytotoxicity. In contrast, Myr-CS-RGD significantly improves drug specificity by reducing CS-RGD toxicity in normal cells while retaining comparable antitumor activity by increasing peptide stability. In a syngeneic mouse tumor model, Myr-CS-RGD demonstrated superior anti-tumor activity compared to CS-piscidin and CS-RGD. Our findings suggest that CS-piscidin can suppress ovarian cancer via multiple cell death forms and that myristoylation modification is a promising strategy to enhance anti-cancer peptide performance.

Lantern-shaped flexible RNA origami for Smad4 mRNA delivery and growth suppression of colorectal cancer

mRNA delivery has shown high application value in the treatment of various diseases, but its effective delivery is still a major challenge at present. Herein, we propose a lantern-shaped flexible RNA origami for mRNA delivery. The origami is composed of a target mRNA scaffold and only two customized RGD-modified circular RNA staples, which can compress the mRNA into nanoscale and facilitate its endocytosis by cells. In parallel, the flexible structure of the lantern-shaped origami allows large regions of the mRNA to be exposed and translated, exhibiting a good balance between endocytosis and translation efficiency. The application of lantern-shaped flexible RNA origami in the context of the tumor suppressor gene, Smad4 in colorectal cancer models demonstrates promising potential for accurate manipulation of protein levels in in vitro and in vivo settings. This flexible origami strategy provides a competitive delivery method for mRNA-based therapies.

Recent Advance of Liposome Nanoparticles for Nucleic Acid Therapy

Gene therapy, as an emerging therapeutic approach, has shown remarkable advantages in the treatment of some major diseases. With the deepening of genomics research, people have gradually realized that the emergence and development of many diseases are related to genetic abnormalities. Therefore, nucleic acid drugs are gradually becoming a new boon in the treatment of diseases (especially tumors and genetic diseases). It is conservatively estimated that the global market of nucleic acid drugs will exceed $20 billion by 2025. They are simple in design, mature in synthesis, and have good biocompatibility. However, the shortcomings of nucleic acid, such as poor stability, low bioavailability, and poor targeting, greatly limit the clinical application of nucleic acid. Liposome nanoparticles can wrap nucleic acid drugs in internal cavities, increase the stability of nucleic acid and prolong blood circulation time, thus improving the transfection efficiency. This review focuses on the recent advances and potential applications of liposome nanoparticles modified with nucleic acid drugs (DNA, RNA, and ASO) and different chemical molecules (peptides, polymers, dendrimers, fluorescent molecules, magnetic nanoparticles, and receptor targeting molecules). The ability of liposome nanoparticles to deliver nucleic acid drugs is also discussed in detail. We hope that this review will help researchers design safer and more efficient liposome nanoparticles, and accelerate the application of nucleic acid drugs in gene therapy.

Cyclic RGD-Decorated Liposomal Gossypol AT-101 Targeting for Enhanced Antitumor Effect

Introduction

(-)-Gossypol (AT-101), the (-)-enantiomer of the natural compound gossypol, has shown significant inhibitory effects on various types of cancers such as osteosarcoma, myeloma, glioma, lung cancer, and prostate cancer. However, the clinical application of (-)-gossypol was often hindered by its evident side effects and the low bioavailability via oral administration, which necessitated the development of suitable (-)-gossypol preparations to settle the problems. In this study, injectable cyclic RGD (cRGD)-decorated liposome (cRGD-LP) was prepared for tumor-targeted delivery of (-)-gossypol.

Methods

The cRGD-LP was prepared based on cRGD-modified lipids. For comparison, a non-cRGD-containing liposome (LP) with a similar chemical composition to cRGD-LP was specially designed. The physicochemical properties of (-)-gossypol-loaded cRGD-LP (Gos/cRGD-LP) were investigated in terms of the drug loading efficiency, particle size, morphology, drug release, and so on. The inhibitory effect of Gos/cRGD-LP on the proliferation of tumor cells in vitro was evaluated using different cell lines. The biodistribution of cRGD-LP in vivo was investigated via the near-infrared (NIR) fluorescence imaging technique. The antitumor effect of Gos/cRGD-LP in vivo was evaluated in PC-3 tumor-bearing nude mice.

Results

Gos/cRGD-LP had an average particle size of about 62 nm with a narrow size distribution, drug loading efficiency of over 90%, and sustained drug release for over 96 h. The results of NIR fluorescence imaging demonstrated the enhanced tumor targeting of cRGD-LP in vivo. Moreover, Gos/cRGD-LP showed a significantly enhanced inhibitory effect on PC-3 tumors in mice, with a tumor inhibition rate of over 74% and good biocompatibility.

Conclusion

The incorporation of cRGD could significantly enhance the tumor-targeting effect of the liposomes and improve the antitumor effect of the liposomal (-)-gossypol in vivo, which indicated the potential of Gos/cRGD-LP that warrants further investigation for clinical applications of this single-isomer drug.

Cationic Liposome Decorated with Cyclic RGD Peptide for Targeted Delivery of anti-STAT3 siRNA to Melanoma Cancer Cells

Gene therapy is regarded as a valuable strategy for efficient cancer treatment. However, the design of effective delivery systems that can deliver gene materials such as siRNA specifically to the tumour tissues plays a pivotal role in cancer therapy. For this reason, a targeted cationic liposome for melanoma treatment was developed. This system consists of cyclic RGD peptide conjugated to DSPE-PEG2000, cholesterol, DOTAP, and DSPC as cationic and neutral lipids, respectively. Cyclic RGD was selected based on speculation that cyclic RGD would effectively transport anti-signal transducer and activator of transcription 3 (STAT3) siRNA into melanoma cell via integrin receptors. The prepared liposomes provided excellent stability against electrolyte and serum nucleases. Targeted liposomes remarkably exhibited higher cellular internalisation in comparison with the non-targeted system in flow cytometry and confocal microscopy. Furthermore, incorporating peptide on the surface of liposomes resulted in considerably high cytotoxicity, a 2.1-times raise in apoptosis induction, and a significantly enhanced STAT3 gene suppression as compared with the corresponding non-targeted formulation on B16F10 murine melanoma cells. Whole-body imaging confirmed the more significant tumour accumulation of targeted liposomes in B16F10 melanoma xenograft tumour-bearing mice. Consequently, c-RGD peptide modified liposome suggests a promising option for specific siRNA delivery into melanoma cells.