A viroid-derived small interfering RNA targets bHLH transcription factor MdPIF1 to regulate anthocyanin biosynthesis in Malus domestica.

Fruit colour is a critical determinant for the appearance quality and commercial value of apple fruits. Viroid-induced dapple symptom severely affects the fruit coloration, however, the underlying mechanism remains unknown. In this study, we identified an apple dimple fruit viroid (ADFVd)-derived small interfering RNA, named vsiR693, which targeted the mRNA coding for a bHLH transcription factor MdPIF1 (PHYTOCHROME-INTERACTING FACTOR 1) to regulate anthocyanin biosynthesis in apple. 5' RLM-RACE and artificial microRNA transient expression system proved that vsiR693 directly targeted the mRNA of MdPIF1 for cleavage. MdPIF1 positively regulated anthocyanin biosynthesis in both apple calli and fruits, and it directly bound to G-box element in the promoter of MdPAL and MdF3H, two anthocyanin biosynthetic genes, to promote their transcription. Expression of vsiR693 negatively regulated anthocyanin biosynthesis in both apple calli and fruits. Furthermore, co-expression of vsiR693 and MdPIF1 suppressed MdPIF1-promoted anthocyanin biosynthesis in apple fruits. Infiltration of ADFVd infectious clone suppressed coloration surrounding the injection sites in apple fruits, while a mutated version of ADFVd, in which the vsiR693 producing region was mutated, failed to repress fruit coloration around the injection sites. These data provide evidence that a viroid-derived small interfering RNA targets host transcription factor to regulate anthocyanin biosynthesis in apple.

Integrated systematic functional screen and fine-mapping decipher the role and genetic regulation of RPS19 in colorectal cancer development.

Despite genome-wide association studies (GWAS) have identified more than 200 risk loci associated with colorectal cancer (CRC), the causal genes or risk variants within these loci and their biological functions remain not fully revealed. Recently, the genomic locus 19q13.2, with the lead SNP rs1800469 was identified as a crucial CRC risk locus in Asian populations. However, the functional mechanism of this region has not been fully elucidated. Here we employed an RNA interfering-based on-chip approach to screen for the genes essential for cell proliferation in the CRC risk locus 19q13.2. Notably, we found that RPS19 exhibited the most significant effect among the identified genes and acted as a critical oncogene facilitating CRC cell proliferation. Subsequently, combining integrative fine-mapping analysis and a large-scale population study consisting of 6027 cases and 6099 controls, we prioritized rs1025497 as a potential causal candidate for CRC risk, demonstrating that rs1025497[A] allele significantly reduced the risk of CRC (OR 0.70, 95% confidence interval = 0.56-0.83, P = 1.12 × 10-6), which was further validated in UK Biobank cohort comprising 5,313 cases and 21,252 controls. Mechanistically, we experimentally elucidated that variant rs1025497 might acted as an allele-specific silencer, inhibiting the expression level of oncogene RPS19 mediated by the transcription suppressive factor HBP1. Taken together, our sturdy unveils the significant role of RPS19 during CRC pathogenesis and delineates its distal regulatory mechanism mediated by rs1025497, advancing our understanding of the etiology of CRC and provided new insights into the personalized medicine of human cancer.

siRNA as potential therapeutic strategy for hypertension.

Hypertension, a well-known cardiovascular disorder noticed by rise in blood pressure, poses a significant global health challenge. The development RNA interfering (RNAi)-based therapies offers a ground-breaking molecular tool, holds promise for addressing hypertension's intricate molecular mechanisms. Harnessing the power of small interfering RNA (siRNA), researchers aim to selectively target and modulate genes associated with hypertension. Furthermore, they aim to downregulate the levels of mRNA by activating cellular nucleases in response to sequence homology between the siRNA and the corresponding mRNA molecule. As a result, genes involved in the cause of disorders linked to a known genetic background can be silenced using siRNA strategy. In the realm of hypertension, siRNA therapy emerges as a potential therapy for prognostics, diagnostics and treatments. It plays an important role in execution of targeting suppression of genes involved in vascular tone regulation, sodium handling, and pathways contributing to high blood pressure. A clinical trial involving intervention like angiotensinogen siRNA (AGT siRNA) is currently being carried out to treat hypertension. Genetic correlations between uromodulin (UMOD) and hypertension are investigated as emerging Non AGT siRNA target. Furthermore, expression of UMOD is responsible for regulation of sodium by modulating the tumor necrosis factor-α and regulating the Na + -K + -2Cl-cotransporter (NKCC2) in the thick ascending limb, which makes it an important target for blood pressure regulation.

Combined RNA interference and gene replacement therapy targeting MFN2 as proof of principle for the treatment of Charcot-Marie-Tooth type 2A.

Mitofusin-2 (MFN2) is an outer mitochondrial membrane protein essential for mitochondrial networking in most cells. Autosomal dominant mutations in the MFN2 gene cause Charcot-Marie-Tooth type 2A disease (CMT2A), a severe and disabling sensory-motor neuropathy that impacts the entire nervous system. Here, we propose a novel therapeutic strategy tailored to correcting the root genetic defect of CMT2A. Though mutant and wild-type MFN2 mRNA are inhibited by RNA interference (RNAi), the wild-type protein is restored by overexpressing cDNA encoding functional MFN2 modified to be resistant to RNAi. We tested this strategy in CMT2A patient-specific human induced pluripotent stem cell (iPSC)-differentiated motor neurons (MNs), demonstrating the correct silencing of endogenous MFN2 and replacement with an exogenous copy of the functional wild-type gene. This approach significantly rescues the CMT2A MN phenotype in vitro, stabilizing the altered axonal mitochondrial distribution and correcting abnormal mitophagic processes. The MFN2 molecular correction was also properly confirmed in vivo in the MitoCharc1 CMT2A transgenic mouse model after cerebrospinal fluid (CSF) delivery of the constructs into newborn mice using adeno-associated virus 9 (AAV9). Altogether, our data support the feasibility of a combined RNAi and gene therapy strategy for treating the broad spectrum of human diseases associated with MFN2 mutations.

Role of Plant Virus Movement Proteins in Suppression of Host RNAi Defense.

One of the systems of plant defense against viral infection is RNA silencing, or RNA interference (RNAi), in which small RNAs derived from viral genomic RNAs and/or mRNAs serve as guides to target an Argonaute nuclease (AGO) to virus-specific RNAs. Complementary base pairing between the small interfering RNA incorporated into the AGO-based protein complex and viral RNA results in the target cleavage or translational repression. As a counter-defensive strategy, viruses have evolved to acquire viral silencing suppressors (VSRs) to inhibit the host plant RNAi pathway. Plant virus VSR proteins use multiple mechanisms to inhibit silencing. VSRs are often multifunctional proteins that perform additional functions in the virus infection cycle, particularly, cell-to-cell movement, genome encapsidation, or replication. This paper summarizes the available data on the proteins with dual VSR/movement protein activity used by plant viruses of nine orders to override the protective silencing response and reviews the different molecular mechanisms employed by these proteins to suppress RNAi.

Antibacterial, Anti-Biofilm and Pro-Migratory Effects of Double Layered Hydrogels Packaged with Lactoferrin-DsiRNA-Silver Nanoparticles for Chronic Wound Therapy.

Antimicrobial resistance and biofilm formation in diabetic foot infections worsened during the COVID-19 pandemic, resulting in more severe infections and increased amputations. Therefore, this study aimed to develop a dressing that could effectively aid in the wound healing process and prevent bacterial infections by exerting both antibacterial and anti-biofilm effects. Silver nanoparticles (AgNPs) and lactoferrin (LTF) have been investigated as alternative antimicrobial and anti-biofilm agents, respectively, while dicer-substrate short interfering RNA (DsiRNA) has also been studied for its wound healing effect in diabetic wounds. In this study, AgNPs were complexed with LTF and DsiRNA via simple complexation before packaging in gelatin hydrogels. The formed hydrogels exhibited 1668% maximum swellability, with a 46.67 ± 10.33 µm average pore size. The hydrogels demonstrated positive antibacterial and anti-biofilm effects toward the selected Gram-positive and Gram-negative bacteria. The hydrogel containing AgLTF at 125 µg/mL was also non-cytotoxic on HaCaT cells for up to 72 h of incubation. The hydrogels containing DsiRNA and LTF demonstrated superior pro-migratory effects compared to the control group. In conclusion, the AgLTF-DsiRNA-loaded hydrogel possessed antibacterial, anti-biofilm, and pro-migratory activities. These findings provide a further understanding and knowledge on forming multipronged AgNPs consisting of DsiRNA and LTF for chronic wound therapy.

Role of the Ribonuclease ONCONASE in miRNA Biogenesis and tRNA Processing: Focus on Cancer and Viral Infections.

The majority of transcribed RNAs do not codify for proteins, nevertheless they display crucial regulatory functions by affecting the cellular protein expression profile. MicroRNAs (miRNAs) and transfer RNA-derived small RNAs (tsRNAs) are effectors of interfering mechanisms, so that their biogenesis is a tightly regulated process. Onconase (ONC) is an amphibian ribonuclease known for cytotoxicity against tumors and antiviral activity. Additionally, ONC administration in patients resulted in clinical effectiveness and in a well-tolerated feature, at least for lung carcinoma and malignant mesothelioma. Moreover, the ONC therapeutic effects are actually potentiated by cotreatment with many conventional antitumor drugs. This review not only aims to describe the ONC activity occurring either in different tumors or in viral infections but also to analyze the molecular mechanisms underlying ONC pleiotropic and cellular-specific effects. In cancer, data suggest that ONC affects malignant phenotypes by generating tRNA fragments and miRNAs able to downregulate oncogenes expression and upregulate tumor-suppressor proteins. In cells infected by viruses, ONC hampers viral spread by digesting the primer tRNAs necessary for viral DNA replication. In this scenario, new therapeutic tools might be developed by exploiting the action of ONC-elicited RNA derivatives.

Small RNAs Participate in Plant-Virus Interaction and Their Application in Plant Viral Defense.

Small RNAs are significant regulators of gene expression, which play multiple roles in plant development, growth, reproductive and stress response. It is generally believed that the regulation of plants' endogenous genes by small RNAs has evolved from a cellular defense mechanism for RNA viruses and transposons. Most small RNAs have well-established roles in the defense response, such as viral response. During viral infection, plant endogenous small RNAs can direct virus resistance by regulating the gene expression in the host defense pathway, while the small RNAs derived from viruses are the core of the conserved and effective RNAi resistance mechanism. As a counter strategy, viruses evolve suppressors of the RNAi pathway to disrupt host plant silencing against viruses. Currently, several studies have been published elucidating the mechanisms by which small RNAs regulate viral defense in different crops. This paper reviews the distinct pathways of small RNAs biogenesis and the molecular mechanisms of small RNAs mediating antiviral immunity in plants, as well as summarizes the coping strategies used by viruses to override this immune response. Finally, we discuss the current development state of the new applications in virus defense based on small RNA silencing.

CT23 knockdown attenuating malignant behaviors of hepatocellular carcinoma cell is associated with upregulation of metallothionein 1.

The cancer-testis antigen 23 (CT23) gene has been reported in association with the pathogenesis and progress of hepatocellular carcinoma (HCC). However, the alterations of gene expression profiling induced by CT23 knockdown in HCC cells remains largely unknown. In this study, the RNA interfering (RNAi) method was used to silence CT23 expression in BEL-7404 cells. Microarray analysis was performed on mRNA extracted from the CT23 knockdown cells and the control cells to determine the alterations of gene expression profiles. The result showed a total of 1051 genes expressed differentially (two-fold change), including 470 genes upregulated and 581 gene downregulated in the CT23 knockdown cells. A bioinformatic analysis showed that the functional differentially expressed genes (DEGs) were linked to cell proliferation, migration, and apoptosis, and metallothionein 1 (MT1) attained the maximum enrichment scores in functional annotation, classification, and pathway analysis of DEGs. Furthermore, Western blot analysis and cell behaviors assays verified that CT23 modulates cell proliferation, migration, and apoptosis by regulating MT1 expression in HCC cells and non-neoplastic hepatocytes. In summary, downregulated CT23 gene in BEL-7404 cells might change the expressions of carcinogenesis and progression related genes in HCC by upregulating MT1 expression, which would provide insight into searching for a novel therapeutic target for HCC.

TIMP1 down-regulation enhances gemcitabine sensitivity and reverses chemoresistance in pancreatic cancer.

The therapeutic effect of gemcitabine (GEM) in pancreatic ductal adenocarcinoma (PDAC) is limited due to low drug sensitivity and high drug resistance. Tissue inhibitor of matrix metalloprotease 1 (TIMP1) is reportedly associated with GEM resistance in PDAC. However, the effect of TIMP1 down-regulation in combination with GEM treatment is unknown. We analyzed the expression of TIMP1 in human PDAC tissue using western blot, quantitative real-time polymerase chain reaction (qRT-PCR), and immunohistochemistry. TIMP1 was highly expressed in PDAC specimens. Kaplan-Meier survival analysis suggested that a higher level of TIMP1 was correlated with poorer overall survival in 103 PDAC patients. The mRNA and protein expression profiles of TIMP1 were explored in the HTERT-HPNE human pancreatic ductal epithelium cell line, five PDAC cell lines (MIA PaCa-2, PANC-1, BxPC-3, Capan2, and SW1990), and two GEM-resistant PDAC cell lines (MIA PaCa-2R and PANC-1R). Compared with HTERT-HPNE, TIMP1 was highly expressed in the PDAC cell lines. In addition, TIMP1 was upregulated in GEM-resistant PDAC cell lines compared with their parental cells. When TIMP1 was knocked-down using short hairpin RNA, GEM-induced cytotoxicity and apoptosis were increased, while colony formation was repressed in MIA PaCa-2, PANC-1, and their GEM-resistant cells. When Bax was activated by BAM7 or Bcl-2 was inhibited by venetoclax, CCK-8 assays demonstrated that GEM sensitivity was restored in GEM-resistant cells. When Bax was down-regulated by siRNA, CCK-8 assays verified that GEM sensitivity was decreased in PDAC cells. The observations that TIMP1 knockdown enhanced GEM sensitivity and reversed chemoresistance by inducing cells apoptosis indicated cooperative antitumor effects of shTIMP1 and GEM therapy on PDAC cells. The combination may be a potential strategy for PDAC therapy.

Treatment of Colon Cancer by Degradable rrPPC Nano-Conjugates Delivered STAT3 siRNA.

BACKGROUND: Drugs that work based on the mechanism of RNA interference have shown strong potential in cancer gene therapy. Although significant progress has been made in small interfering RNA (siRNA) design and manufacturing, ideal delivery system remains a limitation for the development of siRNA-based drugs. Particularly, it is necessary to focus on parameters including delivery efficiency, stability, and safety when developing siRNA formulations for cancer therapy. METHODS: In this work, a novel degradable siRNA delivery system cRGD-R9-PEG-PEI-Cholesterol (rrPPC) was synthesized based on low molecular weight polyethyleneimine (PEI). Functional groups including cholesterol, cell penetrating peptides (CPPs), and poly(ethylene oxide) were introduced to PEI backbone to attain enhanced transfection efficiency and biocompatibility. RESULTS: The synthesized rrPPC was dispersed as nanoparticles in water with an average size of 195 nm and 41.9 mV in potential. rrPPC nanoparticles could efficiently deliver siRNA into C26 clone cancer cells and trigger caveolae-mediated pathway during transmembrane transportation. By loading the signal transducer and activator of transcription 3 (STAT3) targeting siRNA, rrPPC/STAT3 siRNA (rrPPC/siSTAT3) complex demonstrated strong anti-cancer effects in multiple colon cancer models following local delivery. In addition, intravenous (IV) injection of rrPPC/siSTAT3 complex efficiently suppressed lung metastasis tumor progression with ideal in vivo safety. CONCLUSION: Our results provide evidence that rrPPC nanoparticles constitute a potential candidate vector for siRNA-based colon cancer gene therapy.

Dual-action of thermoresponsive gels containing DsiRNA-loaded gold nanoparticles for diabetic wound therapy: Characterization, in vitro safety and healing efficacy.

Diabetic wounds are difficult to treat due to multiple causes, including reduced blood flow and bacterial infections. Reduced blood flow is associated with overexpression of prostaglandin transporter (PGT) gene, induced by hyperglycaemia which causing poor vascularization and healing of the wound. Recently, gold nanoparticles (AuNPs) have been biosynthesized using cold and hot sclerotium of Lignosus rhinocerotis extracts (CLRE and HLRE, respectively) and capped with chitosan (CS) to produce biocompatible antibacterial nanocomposites. The AuNPs have shown to produce biostatic effects against selected gram positive and negative bacteria. Therefore, in this study, a dual therapy for diabetic wound consisting Dicer subtract small interfering RNA (DsiRNA) and AuNPs was developed to improve vascularization by inhibiting PGT gene expression and preventing bacterial infection, respectively. The nanocomposites were incorporated into thermoresponsive gel, made of pluronic and polyethylene glycol. The particle size of AuNPs synthesized using CLRE (AuNPs-CLRE) and HLRE (AuNPs-HLRE) was 202 ± 49 and 190 ± 31 nm, respectively with positive surface charge (+30 to + 45 mV). The thermoresponsive gels containing DsiRNA-AuNPs gelled at 32 ± 1 °C and released the active agents in sufficient amount with good texture and rheological profiles for topical application. DsiRNA-AuNPs and those incorporated into thermoresponsive pluronic gels demonstrated high cell viability, proliferation and cell migration rate via in vitro cultured cells of human dermal fibroblasts, indicating their non-cytotoxicity and wound healing properties. Taken together, the thermoresponsive gels are expected to be useful as a potential dressing that promotes healing of diabetic wounds.

Safety, Efficacy and Pharcacokinetics of Targeted Therapy with The Liposomal RNA Interference Therapeutic Atu027 Combined with Gemcitabine in Patients with Pancreatic Adenocarcinoma. A Randomized Phase Ib/IIa Study.

BACKGROUND: Atu027 is a liposomally formulated short interfering RNA with anti-metastatic activity, which silences the expression of protein kinase N3 (PKN3) in the vascular endothelium. This trial was designed to assess the safety, pharmacokinetics and efficacy of Atu027 in combination with gemcitabine in advanced pancreatic carcinoma (APC). METHODS: In total, 23 patients (pts) with inoperable APC were randomly assigned to gemcitabine combined with two different Atu027 schedules (0.235 mg/kg once weekly vs. 0.235 mg/kg twice weekly). ClinicalTrials.gov Identifier: NCT01808638. RESULTS: The treatment was well-tolerated. There were Grade 3 adverse events (AEs) in 9/11 pts (arm 1) and 11/12 pts (arm 2), while Grade 4 AEs were reported for two pts in each arm. The AEs were mainly laboratory abnormalities without clinical significance. The median progression-free survival reached statistical significance in patients who had metastatic disease (1.6 vs. 2.9 months, p = 0.025). Disease control during treatment was achieved in 4/11 pts (arm 1) and in 7/12 pts (arm 2). Pts in arm 1 experienced stable global health status while pts in arm 2 reported improvement. CONCLUSIONS: Combining Atu027 with gemcitabine is safe and well tolerated. In pts with metastatic APC, twice-weekly Atu027 is associated with significantly improved outcomes. Our clinical results support the significant involvement of the vascular endothelium in the spread of cancer, and thus the further investigation of its target role.

[Reinforcement of Rhodobacter sphaeroides cofactor NADPH to increase the production of farnesol].

Farnesol (FOH) is produced by dephosphorylation of farnesyl diphosphate (FPP) derived from two universal building blocks, dimethylallyl diphosphate (DMAPP) and isopentenyl diphosphate (IPP). In Rhodobacter sphaeroides these building blocks are generated by MEP pathway, however, many of the biosynthetic reactions and biotransformations in the MEP pathway are limited by low availability of NADPH. Improvement of the amount of intracellular NADPH may enhance the synthesis of FOH. In this study, we utilized the strategies of increasing the production of NADPH and decreasing the consumption of NADPH. The expression of glucose 6-phosphate isomerase (pgi) and glutamate dehydrogenase (gdhA) were inhibited by RNA interference, respectively, and overexpression of 6-glucose phosphate dehydrogenase (zwf) and 6-glucose phosphate dehydrogenase (gnd) in the pentose phosphate pathway were carried out. The results showed that the content of NADPH in the recombinant strains increased significantly, the highest FOH production of RSpgii in the RNA interfered strain was 3.91 mg/g, and the FOH production increased to 3.43 mg/g after zwf gene and gnd gene has been overexpressed. In order to obtain strains with higher FOH production, we used RSpgii as the starting strain, and zwf, gnd and co-overexpressed zwf + gnd gene were overexpressed in RSpgii, respectively. The highest FOH production of the strain RSzgpi reached to 4.48 mg/g which was 2.24 times that of the starting strain RS-GY2.

Novel developments of hepatitis B: treatment goals, agents and monitoring tools.

INTRODUCTION: Chronic hepatitis B (CHB) infection causes considerable morbidity and mortality and hence should be a target for global elimination. In recent years, advances have been made in understanding the disease pathophysiology and the relationship to clinical outcome. Novel treatment targets are actively being sought in the hope of improving the treatment outlook. Areas covered: We discussed the cascade of cure of CHB with respect to the degree of persistence of viral genome and proteins. Several novel antiviral agents either targeting the virus or the host are in different clinical phases of development. Serum hepatitis B core-related antigen and HBV RNA are novel markers, which might have a role in the prediction of specific clinical outcomes such as development of hepatocellular carcinoma or virological relapse after cessation of antiviral therapy. These markers may also be used to monitor treatment response in the drug trials. Expert commentary: Global elimination of CHB is challenged by extremely low awareness of illness and poor access to care. CHB and its related complications can be reduced by birth dose vaccine, antiviral therapy, and alleviated by complication screening. Treatment options for CHB will expand in the next decade and early functional cure is not an impractical goal.

Exosome-based small RNA delivery: Progress and prospects.

RNA interfering (RNAi), mediated by small interfering RNAs and microRNAs, is currently one of the most promising tools of gene therapy. Small RNAs are capable of inducing specific post-transcriptional gene silencing, providing a potentially effective platform for the treatment of a wide array of diseases. However, similar to other nucleic acid-based drugs, the major hurdle of RNAi therapy is lack of efficient and non-immunogenic delivery vehicles. Currently, viruses, synthetic polymers, and lipid-based carriers are among the most widely studied vehicles for small RNA delivery. However, many drawbacks are reported to be associated with these delivery vehicles. There is a pressing need to replace them with more efficient and better-tolerated approaches. Exosomes secreted from the endocytic compartment of live cells, are a subtype of endogenous extracellular vesicles that transfer genetic and biochemical information among different cells, thus playing an important role in cell-cell communication. Recently, accumulating attention has been focused on harnessing exosomes as nanaocarriers for small RNAs delivery. Due to their natural role in shuttling endogenous nucleic acid in our body, exosomes may exhibit higher delivery efficiency, lower immunogenicity, and better compatibility than existing foreign RNA carriers. Importantly, exosomes own intrinsic homing capacity that can guide small RNAs across natural membranous barriers. Moreover, such a capacity can be further improved by adding appropriate targeting moieties. In this manuscript, we briefly review the progress and challenges of RNAi therapy, and discuss the potential of exosomes' applications in small RNA delivery with focus on the most recent advances in exosome-based small RNA delivery for disease therapy.

Amelioration of cirrhotic portal hypertension by targeted cyclooxygenase-1 siRNA delivery to liver sinusoidal endothelium with polyethylenimine grafted hyaluronic acid.

Portal hypertension (PH), a leading cause of mortality in cirrhosis, lacks effective clinical therapeutic strategies. The increased thromboxane A2 (TXA2), derived primarily from the upregulation of cyclooxygenase-1 (COX-1) in cirrhotic liver sinusoidal endothelial cells (LSECs), is responsible for hepatic endothelial dysfunction and PH. Thus, blocking the COX-1 pathway in cirrhotic LSECs may benefit the treatment of PH. In this study, hyaluronate-graft-polyethylenimine (HA-PEI) was synthesized for the targeted delivery of COX-1 siRNA to LSECs. Compared to non-targeted PEI, HA-PEI mediated much more efficient siRNA delivery, which resulted in potent targeted gene silencing in LSECs. In vivo, HA-PEI notably increased the accumulation of siRNA along the sinusoidal lining of the liver, inhibited over-activation of the COX-1/TXA2 pathway in LSECs, and successfully reduced portal pressure in cirrhotic mice. These results highlight the potential of HA-PEI complexed siRNA to serve as a LSECs-specific nanomedical system for effective gene therapy in PH.

Quantum Dots-siRNA Nanoplexes for Gene Silencing in Central Nervous System Tumor Cells.

RNA interfering (RNAi) using short interfering RNA (siRNA) is becoming a promising approach for cancer gene therapy. However, owing to the lack of safe and efficient carriers, the application of RNAi for clinical use is still very limited. In this study, we have developed cadmium sulphoselenide/Zinc sulfide quantum dots (CdSSe/ZnS QDs)-based nanocarriers for in vitro gene delivery. These CdSSe/ZnS QDs are functionalized with polyethyleneimine (PEI) to form stable nanoplex (QD-PEI) and subsequently they are used for siRNA loading which specially targets human telomerase reverse transcriptase (TERT). High gene transfection efficiency (>80%) was achieved on two glioblastoma cell lines, U87 and U251. The gene expression level (49.99 ± 10.23% for U87, 43.28 ± 9.66% for U251) and protein expression level (51.58 ± 7.88% for U87, 50.69 ± 7.59% for U251) of TERT is observed to decrease substantially after transfecting the tumor cells for 48 h. More importantly, the silencing of TERT gene expression significantly suppressed the proliferation of glioblastoma cells. No obvious cytotoxicity from these QD-PEI nanoplexes were observed over at 10 times of the transfected doses. Based on these results, we envision that QDs engineered here can be used as a safe and efficient gene nanocarrier for siRNA delivery and a promising tool for future cancer gene therapy applications.

Thermoresponsive curcumin/DsiRNA nanoparticle gels for the treatment of diabetic wounds: synthesis and drug release.

AIM: Chitosan (CS) has been extensively studied as drug delivery systems for wound healing. Results/methodology: CS nanoparticles were loaded with curcumin (Cur) and DsiRNA against prostaglandin transporter gene and they were incorporated into 20 and 25% w/v Pluronic F-127. The gels were later analyzed for their rheology, gelation temperature (Tgel), morphology, drug incorporation and in vitro drug release. The particle size was in the range of 231 ± 17-320 ± 20 nm, depending on CS concentration. The gels had Tgel of 23-28°C and exhibited sustained drug release with high accumulated amount of drugs over 48 h. CONCLUSION: A thermo-sensitive gel containing Cur/DsiRNA CS nanoparticles was successfully developed and has a great potential to be further developed.

Endogenous bone morphogenetic protein 2 plays a role in vascular smooth muscle cell calcification induced by interleukin 6 in vitro.

Systemic inflammation is involved in vascular calcification and cardiovascular disease which is the leading cause of mortality in rheumatoid arthritis (RA). A high level of serum interleukin (IL)-6 plays a key role in local and systemic inflammation in RA. However, the underlying mechanisms remain unclear. We established a human umbilical artery smooth muscle cell (HUASMC) culturing method to investigate the possible role of IL-6 on vascular calcification. HUASMCs were obtained from umbilical arteries of healthy neonates. To detect calcification effects, HUASMCs were treated with (experimental group) or without (control group) recombinant human (rh) IL-6. The calcium deposition stain and calcium concentrations were measured, as well as the mRNA and protein levels of the regulating factor of osteogenic differentiation-bone morphogenetic protein (BMP) 2 and those calcifying related molecules including bone-specific alkaline phosphatase (BAP), osteoprotegerin (OPG), and osteopontin (OPN). Our study showed that rhIL-6 induced calcification of HUASMCs in a time- and dose-dependent manner, and upregulated expressions of BMP2, BAP, OPG, and OPN of HUASMCs. We then used the anti-BMP2 siRNA to knockdown the expression of endogenous BMP2 to confirm its role. HUASMCs were transfected with negative siRNA (control group) or the valid anti-BMP2 siRNA (experimental group) before they were treated with rhIL-6. Cells transfected with negative siRNA without IL-6 stimulating served as the blank group. The results showed that anti-BMP2 siRNA markedly decreased expressions of BMP2, BAP, OPG, and OPN, and also partly reduced the calcification of HUASMCs induced by rhIL-6. Collectively, according to our study, rhIL-6 could induce the extracellular calcification and osteogenic differentiation of human artery smooth muscle cells through upregulating endogenous BMP2 in vitro. This may be one of the underlying mechanisms of the overwhelming vascular calcification in RA.