Recent Advances in Immune Regulation by Targeting Dendritic Cells using Small Interfering RNAs.

Gene silencing through RNA interference (RNAi) technology has provided forceful therapeutic modalities to specific knockdown of the genes' expression related to diseases. Small interfering RNAs (siRNAs) can start a process that specifically degrades and silences the expression of cognate mRNAs. These RNA interference processes could effectively adjust many biological processes, including immune responses. Dendritic cells (DCs) are specialist antigen-presenting cells with potent functions in regulating innate and adaptive immunity. SiRNAs performed vital roles in coordinating immune processes mediated by DCs. This review describes the findings that shed light on the significance of siRNAs in DC immune regulation and highlight their potential applications for improving DC-based immunotherapies.

Recent advances and applications of peptide-agent conjugates for targeting tumor cells.

BACKGROUND: Cancer, being a complex disease, presents a major challenge for the scientific and medical communities. Peptide therapeutics have played a significant role in different medical practices, including cancer treatment. METHOD: This review provides an overview of the current situation and potential development prospects of anticancer peptides (ACPs), with a particular focus on peptide vaccines and peptide-drug conjugates for cancer treatment. RESULTS: ACPs can be used directly as cytotoxic agents (molecularly targeted peptides) or can act as carriers (guiding missile) of chemotherapeutic agents and radionuclides by specifically targeting cancer cells. More than 60 natural and synthetic cationic peptides are approved in the USA and other major markets for the treatment of cancer and other diseases. Compared to traditional cancer treatments, peptides exhibit anticancer activity with high specificity and the ability to rapidly kill target cancer cells. ACP's target and kill cancer cells via different mechanisms, including membrane disruption, pore formation, induction of apoptosis, necrosis, autophagy, and regulation of the immune system. Modified peptides have been developed as carriers for drugs, vaccines, and peptide-drug conjugates, which have been evaluated in various phases of clinical trials for the treatment of different types of solid and leukemia cancer. CONCLUSIONS: This review highlights the potential of ACPs as a promising therapeutic option for cancer treatment, particularly through the use of peptide vaccines and peptide-drug conjugates. Despite the limitations of peptides, such as poor metabolic stability and low bioavailability, modified peptides show promise in addressing these challenges. Various mechanism of action of anticancer peptides. Modes of action against cancer cells including: inducing apoptosis by cytochrome c release, direct cell membrane lysis (necrosis), inhibiting angiogenesis, inducing autophagy-mediated cell death and immune cell regulation.

Exosomal microRNAs: A Diagnostic and Therapeutic Small Bio-molecule in Esophageal Cancer.

Esophageal cancer (EC) is one of the major causes of cancer-related death worldwide. EC is usually diagnosed at a late stage, and despite aggressive therapy, the five-year survival rate of patients remains poor. Exosomes play important roles in cancer biology. Indeed, exosomes are implicated in tumor proliferation, angiogenesis, and invasion. They contain bioactive molecules such as lipids, proteins, and non-coding RNAs. Exosome research has recently concentrated on microRNAs, which are tiny noncoding endogenous RNAs that can alter gene expression and are linked to nearly all physiological and pathological processes, including cancer. It is suggested that deregulation of miRNAs results in cancer progression and directly induces tumor initiation. In esophageal cancer, miRNA dysregulation plays an important role in cancer prognosis and patients' responsiveness to therapy, indicating that miRNAs are important in tumorigenesis. In this review, we summarize the impact of exosomal miRNAs on esophageal cancer pathogenesis and their potential applications for EC diagnosis and therapy.

The modulatory role of dendritic cell-T cell cross-talk in breast cancer: Challenges and prospects.

Antigen recognition and presentation are highlighted as the first steps in developing specialized antigen responses. Dendritic cells (DCs) are outstanding professional antigen-presenting cells (APCs) responsible for priming cellular immunity in pathological states, including cancer. However, the diminished or repressed function of DCs is thought to be a substantial mechanism through which tumors escape from the immune system. In this regard, DCs obtained from breast cancer (BC) patients represent a notably weakened potency to encourage specific T-cell responses. Additionally, impaired DC-T-cell cross-talk in BC facilitates the immune evade of cancer cells and is connected with tumor advancement, immune tolerance, and adverse prognosis for patients. In this review we aim to highlight the available knowledge on DC-T-cell interactions in BC aggressiveness and show its therapeutic potential in BC treatment.

The regulatory role of autophagy-related miRNAs in lung cancer drug resistance.

Autophagy is conserved cellular machinery that degrades un-usable proteins and cellular components and has a crucial role in the pathogenesis and drug resistance of various diseases such as lung cancer (LC). Multiple types of endogenous molecules (i.e. miRNAs) have been found to regulate multiple biological processes, such as autophagy. Dysfunction of these molecules is associated with the onset and progression of a variety of human malignancies. Several studies had shown that some miRNAs could mediate autophagy activity in LC cells, which would affect drug resistance as a major problem in LC therapy. Therefore, identifying the underlying molecular targets of miRNAs and their function in autophagy pathways could develop new treatment interventions for LC patients. In this review, we will summarize the interplay between miRNAs, autophagy, and drug resistance of LC patients, as well as the genes and molecular pathways that are involved.

Knockdown of Myeloid Cell Leukemia-1 by MicroRNA-101 Increases Sensitivity of A549 Lung Cancer Cells to Etoposide.

Background: Studies have shown that myeloid cell leukemia-1 (Mcl-1) is the target gene for microRNA -101 (miRNA-101), and decreased levels of miRNA-101 are associated with elevated levels of Mcl-1 and lung cancer survival. The objective of the present study was to investigate the effect of miRNA-101 on the sensitivity of A549 lung cancer cells to etoposide. Methods: The study was conducted during 2018 and 2019 at Arak University of Medical Sciences, Arak, Iran. The effect of miRNA-101 on Mcl-1 expression was assessed using reverse transcription-quantitative polymerase chain reaction 3-(4, 5-Dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT), and trypan blue exclusion assays were performed to determine the effect of treatments on cell survival and proliferation, respectively. The interaction between miRNA-101 and etoposide was evaluated using the combination index analysis of Chou-Talalay. Apoptosis was quantified using ELISA cell death assay. ANOVA and Bonferroni's tests were used to determine statistical differences between the groups (P<0.05). GraphPad Prism software (version 6.01) was used for data analysis. Results: The results showed that miRNA-101 clearly inhibited the expression of Mcl-1 and reduced the growth of A549 cells, relative to blank control and negative control miRNA (P<0.05). Transfection of miRNA-101 synergistically enhanced the sensitivity of the A549 cells to etoposide. Apoptosis assay data also showed that miRNA-101 triggered apoptosis and augmented the etoposide-mediated apoptosis. Conclusion: Up-regulation of miRNA-101 inhibited cell survival and proliferation, and sensitized A549 cells to etoposide by suppressing Mcl-1 expression. miRNA-101 replacement therapy can be considered as an effective therapeutic strategy in non-small cell lung cancer.

Therapeutic Measures for the Novel Coronavirus: A Review of Current Status and Future Perspective.

The coronavirus disease 19 (COVID-19) is a highly pathogenic and transmissible viral disease caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which originated in the city of Wuhan, Hubei Province, Central China and spread quickly around the world. The genome sequence of SARSCoV- 2 is phylogenetically related to bat-derived severe acute respiratory syndrome-like (SARS-like) coronaviruses; therefore bats could be the possible primary reservoirs. At present, there are no clinically approved vaccines or specific antiviral drugs for COVID- 19. However, several broad-spectrum antiviral drugs have been evaluated against COVID-19 in clinical studies and resulted in the improvement of patients. In this regard, other therapies such as antiviral drugs, antibodies, stem cells and plasma therapy are being studied. In the current study, we reviewed the emergence, pathogenicity and the genome structure of COVID-19 infection. The main focus of this study is on the therapeutic approaches that may be effective against SARS-CoV-2.

Gene Therapy with MiRNA-Mediated Targeting of Mcl-1 Promotes the Sensitivity of Non-Small Cell Lung Cancer Cells to Treatment with ABT-737.

BACKGROUND: Despite the dramatic efficacy of ABT-737, a large percentage of cancer cells ultimately become resistance to this drug. Evidences show that over-expression of Mcl-1 is linked to ABT-737 resistance in NSCLC cells. The aim of this study was to investigate the effect of miRNA-101 on Mcl-1 expression and sensitivity of the A549 NSCLC cells to ABT-737. METHODS: After miRNA-101 transfection, the Mcl-1 mRNA expression levels were quantified by RT-qPCR. Trypan blue staining was used to explore the effect of miRNA-101 on cell growth. The cytotoxic effects of miRNA-101 and ABT-737, alone and in combination, were measured using MTT assay. The effect of drugs combination was determined using the method of Chou-Talalay. Cell death was assessed using cell death detection ELISA assay kit. RESULTS: Results showed that miRNA-101 markedly suppressed the expression of Mcl-1 mRNA in a time dependent manner, which led to A549 cell proliferation inhibition and enhancement of apoptosis (p < 0.05, relative to blank control). Pretreatment with miRNA-101 synergistically decreased the cell survival rate and lowered the IC50 value of ABT-737. Furthermore, miRNA-101 dramatically enhanced the apoptotic effect of ABT-737. Negative control miRNA had no remarkable effect on cellular parameters. CONCLUSIONS: Our findings propose that suppression of Mcl-1 by miRNA-101 can effectively inhibit the cell growth and sensitize A549 cells to ABT-737. Therefore, miRNA-101 can be considered as a potential therapeutic target in patients with non-small cell lung cancer.
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