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Background: Curcumin is a polyphenol compound with many therapeutic effects. Despite the anti -tumor, antioxidant and anti - inflammatory properties of this pigment, due to poor solubility and instability in the aqueous environments and physiological conditions of the body, its application in the treatment of diseases has been limited. Today researchers are trying to design an efficient nanocarrier for employing this pigment in pharmaceutical applications. Exosomes are lipid nanovesicles are released into the extracellular environment by all types of cells and are responsible for the transfer of biological materials between cells, so they are considered the best candidate for this goal. In this study, we aimed to load curcumin into the exosomes to increase its solubility and stability and facilitate its delivery into ovarian cancer cells. Methods: After isolating the exosome by ultracentrifugation and verifying its structure with SEM, TEM and DLS, curcumin was loaded into the exosome by three methods of incubation, sonication and freeze-thaw cycles. Then, using MTT assay, the toxicity effect of curcumin on SKOV3 cells was investigated. Results: The results showed that the amount of curcumin loading into exosome was very low (less than 10%) and it was found that sonication and freeze-thaw cycles have no effect on increasing the loading of curcumin into the exosome. Based on the results of the toxicity test, IC50 value of free curcumin and exosome-loaded curcumin was 150 µg/ml and 200 µg/ml, respectively. Although the loading percentage of curcumin in the exosome was very low, the MTT results showed that the loading of curcumin in the exosome plays a significant role in its efficient delivery to SKOV3 cells. Conclusions: It can be concluded that despite the very high stability of exosomes and the safety of these cellular nanovesicles, for better efficiency in drug delivery, more studies should be done for optimizing the methods of drug loading into exosomes. [ABSTRACT FROM AUTHOR]

Colorectal cancer (CRC) is recognized as one of the most common gastrointestinal malignancies across the globe. Despite significant progress in designing novel treatments for CRC, there is a pressing need for more effective therapeutic approaches. Unfortunately, many patients undergoing chemotherapy develop drug resistance, posing a significant challenge for cancer treatment. Non‐coding RNAs (ncRNAs) have been found to play crucial roles in CRC development and its response to chemotherapy. However, there are still gaps in our understanding of interactions among various ncRNAs, such as long non‐coding RNAs (lncRNAs), circular RNAs (circRNAs) and microRNAs (miRNAs). These ncRNAs can act as either oncogenes or tumour suppressors, affecting numerous biological functions in different cancers including CRC. A class of ncRNA molecules known as competitive endogenous RNAs (ceRNAs) has emerged as a key player in various cellular processes. These molecules form networks through lncRNA/miRNA/mRNA and circRNA/miRNA/mRNA interactions. In CRC, dysregulation of ceRNA networks has been observed across various cellular processes, including proliferation, apoptosis and angiogenesis. These dysregulations are believed to play a significant role in the progression of CRC and, in certain instances, may contribute to the development of chemoresistance. Enriching our knowledge of these dysregulations holds promise for advancing the field of diagnostic and therapeutic modalities for CRC. In this review, we discuss lncRNA‐ and circRNA‐associated ceRNA networks implicated in the emergence and advancement of drug resistance in colorectal carcinogenesis. [ABSTRACT FROM AUTHOR]

Given that tumor cells primarily instigate systemic changes through exosome secretion, our study delved into the role of colorectal cancer (CRC)-secreted exosomal miR-224 in stromal reprogramming and its impact on endothelial cell angiogenesis. Furthermore, we assessed the potential clinical significance of a specific signature of circulating serum-derived miRNAs, serving as a non-invasive biomarker for CRC diagnosis. Circulating serum-derived miR-103a-3p, miR-135b-5p, miR-182-5p, and miR-224-5p were significantly up-regulated, while miR-215-5p, and miR-455-5p showed a significant down-regulation in CRC patients than in healthy individuals. Our findings indicated that the expressions of CAF-specific markers (a-SMA and FAP) and CAF-derived cytokines (IL-6, and SDF-1) were induced in fibroblasts stimulated with SW480 CRC exosomes, partly due to Akt activation. As a plausible mechanism, exosomal transfer of miR-224 from SW40 CRC cells may activate stromal fibroblasts, which in turn, may promote endothelial cell sprouting. The study identified PHLPP1 and PHLPP2 as direct targets of miR-224 and demonstrated that CRC-secreted exosomal miR-224 activates Akt signaling by regulating PHLPP1/2 in activated fibroblasts, thereby affecting the stromal cell proliferation and migration. This study established a panel of six-circulating serum-derived miRNAs as a non-invasive biomarker for CRC diagnosis. Also, we proposed a supporting model in which CRC-secreted exosomal miR-224 takes part in the stromal reprogramming to CAFs partly through regulating Akt signaling. This may affect the malignant biological behavior of activated stromal cells and thereby elicit a vascular response within the microenvironment of CRC cells. [ABSTRACT FROM AUTHOR]

Background: Megakaryopoiesis is characterized by progressive polyploidization and the expression of megakaryocytic markers. Numerous transcription factors and physiological signaling pathways regulate this phenomenon. Megakaryocyte differentiation induction in the K562 cell line and hematopoietic stem cells via nanocurcumin drug has been identified in our previous study. K562 cells are typical Chronic Myelogenous Leukemia (CML) cells that are resistant to apoptosis and express the bcr-abl fusion gene. These cells have the potential to differentiate into erythrocytes and megakaryocytes. Curcumin is well known as a component with strong potential to alter NFκB activity in various cells. NFκB pathway regulates various genes such as apoptotic and immune response genes. The aim of the current study is to evaluate the possible role of nanocurcumin in NFκB pathway regulation during the megakaryopoiesis process in the K562 cell line. Materials and Methods: Megakaryocyte markers expression and phenotype alteration of nanocurcumintreated K562 cells have been detected by flow cytometry and microscopy imaging. The nuclear level of the RelA (p65) subunit of NFκB was determined by western blot test in K562 cells during megakaryopoiesis induction via nanocurcumin treatment at different times. The expression of NFκB target genes including c-MYC, BAX, and NQO1 was also analyzed in nanocurcumin-treated K562 cells by quantitative RT-PCR assay at different times. Results: It was demonstrated that nanocurcumin leads to an increase in NFκB activity transiently during megakaryocyte differentiation, which is followed by a change in the expression of c-MYC, BAX, and NQO1 target genes. Conclusion: The NFκB pathway can be considered a new pathway for inducing megakaryocyte differentiation by nanocurcumin for the purposes of in vitro and in vivo megakaryopoiesis experiments. [ABSTRACT FROM AUTHOR]

Hepatocellular carcinoma (HCC), as the most prevalent liver malignancy, is annually diagnosed in more than half a million people worldwide. HCC is strongly associated with hepatitis B and C viral infections as well as alcohol abuse. Obesity and nonalcoholic fatty liver disease (NAFLD) also significantly enhance the risk of liver cancer. Despite recent improvements in therapeutic approaches, patients diagnosed in advanced stages show poor prognosis. Accumulating evidence provides support for the regulatory role of non‐coding RNAs (ncRNAs) in cancer. There are a variety of reports indicating the regulatory role of microRNAs (miRNAs) in different stages of HCC. Long non‐coding RNAs (LncRNAs) exert their effects by sponging miRNAs and controlling the expression of miRNA‐targeted genes. Circular RNAs (circRNAs) perform their biological functions by acting as transcriptional regulators, miRNA sponges and protein templates. Diverse studies have illustrated that dysregulation of competing endogenous RNA networks (ceRNETs) is remarkably correlated with HCC‐causing diseases such as chronic viral infections, nonalcoholic steatohepatitis and liver fibrosis/cirrhosis. The aim of the current article was to provide an overview of the role and molecular mechanisms underlying the function of ceRNETs that modulate the characteristics of HCC such as uncontrolled cell proliferation, resistance to cell death, metabolic reprogramming, immune escape, angiogenesis and metastasis. The current knowledge highlights the potential of these regulatory RNA molecules as novel diagnostic biomarkers and therapeutic targets in HCC. [ABSTRACT FROM AUTHOR]

microRNAs (miRNAs or miRs) play key roles in different stages of chronic myeloid leukemia (CML) pathogenesis. The present study aimed to demonstrate whether miR-155 enables CD34+ CML cells to escape from the growth-inhibitory effects of TGF-β1 and bone morphogenetic protein (BMP) signaling. Among differentially expressed miRNAs in CD34+ CML cells, miR-155 was highly up-regulated. QRT-PCR revealed an inverse correlation between miR-155 and two key members of the TGF-β pathway—TGF-βR2 and SMAD5. Results showed that SMAD5 is not only up-regulated through BMPs treatment, but recombinant TGF-β1 can also induce SMAD5 in CML cells. We also demonstrated that TGF-β1-mediated phosphorylation of SMAD1/5 was abolished by pretreatment with the blocking TGF-βR2 antibody, suggesting a possible involvement of TGF-βR2. Additionally, overexpression of miR-155 significantly promoted the proliferation rate of CD34+ CML cells. Results showed that siRNA-mediated knockdown of SMAD5 had a promoting effect on CD34+ CML cell proliferation, suggesting that SMAD5 knock-down recapitulates the proliferative effects of miR-155. Importantly, TGF-β1 and BMP2/4 treatment had inhibitory effects on cell proliferation; however, miR-155 overexpression enabled CD34+ CML cells to evade the anti-proliferative effects of TGF-β1 and BMPs. Consistently, down-regulation of miR-155 augmented the promoting effects of TGF-β1 and BMP signaling on inducing apoptosis in CD34+ CML stem cells. Our findings demonstrated that targeting of SMAD5 and TGF-βR2 links miR-155 to TGF-β signaling in CML. Overexpression of miR-155 enables CD34+ CML cells to evade growth-inhibitory effects of the TGF-β1 and BMP signaling, providing new perspectives for miR-155 as a therapeutic target for CML. [ABSTRACT FROM AUTHOR]

Multiple sclerosis (MS) is a demyelinating disease of the central nervous system (CNS), characterized by neuroinflammation, oligodendrocytes (OLs) loss, and demyelination Curcumin, a natural phenolic substance, has been shown to have significant therapeutic properties in various neurodegenerative diseases, including MS. In our laboratory by loading curcumin in dendrosome nanoparticles we improved its solubility and bioavailability. Our previous study showed antiinflammatory and anti-oxidative effects of dendrosomal nano-curcumin (DNC) in experimental autoimmune encephalomyelitis (EAE) model of MS. Here, by using a toxic demyelination model, induced by cuprizone (CPZ), we investigated the protective effect of DNC on oligodendroglial lineage cells (OLLC) and myelin preservation in context of acute demyelination. CPZ is a copper chelator, thus its intake reduces the mitochondrial activity, activates oxidative stress response, leading to specific OLs death, due to their high-energy consumption. We also evaluated DNC effect on activation of astrocytes and microglia, which are enriched in both MS and CPZ demyelinated lesions. Our results demonstrated that DNC treatment protected Oligodendrocyte lineage cells (OLLCs) against CPZ toxin. Besides DNC treatment suppressed accumulation of astrocytes and microglia in CC of CPZ-fed mice, compared to PBS treated onse. Moreover, DNC treatment lead to higher index of luxol fast bluefast blue (LFB) and myelin-specific proteins, myelin basic protein (MBP) intensity in the corpus callosum (CC), as indicators of myelin content. These results suggest a potent pleiotropic therapeutic efficiency for DNC for protection of myelinating cells, possibly via suppression of astrocytes and microglia. [ABSTRACT FROM AUTHOR]