A universal gene carrier platform for treatment of human prostatic carcinoma by p53 transfection

Caspase-3 and gasdermin E mediate macrophage pyroptosis in periodontitis

BACKGROUND AND OBJECTIVES

Periodontitis is a chronic inflammatory disease linked to pyroptosis, an inflammatory cell death process. Macrophages are essential for maintaining microenvironment homeostasis, which is crucial for periodontal health. This study explores the mechanisms underlying the relationship between macrophage pyroptosis and periodontitis.

METHODS

Expression of the pyroptosis marker gasdermin E (GSDME) and the macrophage surface marker CD68 was examined by immunofluorescence double staining in healthy and periodontitis gingival tissues. In an in vitro pyroptosis model, RAW264.7 cells were irritated using Porphyromonas gingivalis-lipopolysaccharide (P. gingivalis-LPS) after treatment with either a nuclear factor kappa-B (NF-κB) agonist or inhibitor. The mRNA and protein levels of NF-κB, caspase-3, GSDME, and interleukin-1β (IL-1β) were evaluated through qRT-PCR, western blotting, and ELISA techniques.

RESULTS

GSDME and CD68 were heavily elevated in inflamed gingival tissues compared to healthy tissues and co-localized in the same region. Furthermore, exposure to P. gingivalis-LPS resulted in a significant upregulation of NF-κB, caspase-3, GSDME, and IL-1β at both the mRNA and protein levels in RAW264.7 cells. NF-κB agonist or inhibitor pretreatment enhanced or inhibited these effects.

CONCLUSIONS

GSDME-mediated macrophage pyroptosis is implicated in periodontitis. Based on in vitro experiments, P. gingivalis-LPS causes pyroptosis in RAW264.7 cells through the caspase-3/GSDME pathway. Furthermore, NF-κB regulates this pyroptotic pathway.

AKT activation by SC79 to transiently re-open pathological blood brain barrier for improved functionalized nanoparticles therapy of glioblastoma

Glioblastoma (GBM) is one of the malignant tumors with high mortality, and the presence of the blood brain barrier (BBB) severely limits the penetration and tissue accumulation of therapeutic agents in the lesion of GBM. Active targeting nanotechnologies can achieve efficient drug delivery in the brain, while still have a very low success rate. Here we revealed a previously unexplored phenomenon that chemotherapy with active targeting nanotechnologies causes pathological BBB functional recovery through VEGF-PI3K-AKT signaling pathway inhibition, accompanied with up-regulated expression of Claudin-5 and Occludin. Seriously, pathological BBB functional recovery induces a significant decrease of intracerebral active targeting nanotechnologies transport during GBM multiple administration, leading to chemotherapy failure in GBM therapeutics. To address this issue, we chose AKT agonist SC79 to transiently re-open functional recovering pathological BBB for continuously intracerebral delivery of brain targeted nanotherapeutics, finally producing an observable anti-GBM effect in vivo, which may offer new sight for other CNS disease treatment.

Redox-responsive polymer inhibits macrophages uptake for effective intracellular gene delivery and enhanced cancer therapy

The development of advanced gene delivery carriers with stimuli-responsive release manner for tumor therapeutics is desirable, since they can exclusively release the therapeutic gene via their structural changes in response to the specific stimuli of the target site. Moreover, interactions between macrophages and drug delivery systems (DDSs) seriously impair the treatment efficiency of DDSs, thus macrophages uptake inhibition would to some extent improve the intracellular uptake of DDSs in tumor cells. Herein, a PEGylated redox-responsive gene delivery system was developed for effective cancer therapy. PEG modified glycolipid-like polymer (P-CSSO) was electrostatic interacted with p53 to form P-CSSO/p53 complexes, which exhibited an enhanced redox sensitivity in that the disulfide bond was degraded and the rate the plasmid released from P-CSSO was 2.29-fold that of nonresponsive platform (P-CSO-SA) in 10 mM levels of glutathione (GSH). PEGylation could significantly weaken macrophages uptake, while enhance the accumulation of P-CSSO in tumor cells both in vitro and in vivo. Compared with nonresponsive complexes (P-CSO-SA/p53) (59.2%) and Lipofectamine™ 2000/p53 complexes (52.0%), the tumor inhibition rate of P-CSSO/p53 complexes (77.1%) significantly increased, which was higher than CSSO/p53 complexes (69.9%). The present study indicates that tumor microenvironment sensitive and macrophages uptake suppressive P-CSSO/p53 is a powerful in vivo gene delivery system for enhanced anticancer therapy.

Dendritic Cells Targeting and pH-Responsive Multi-layered Nanocomplexes for Smart Delivery of DNA Vaccines

Specific and effective delivery of DNA vaccines into dendritic cells (DCs) to express antigens is a precondition for induction of immune responses. Construction of a new DNA vaccine delivery system with the ability of programmed gene transfection may achieve this objective. In this study, we successfully integrated dendritic lipopeptide, charge-reversible polymer, and APC-targeted material into DNA vaccine delivery system through layer-by-layer (LBL) assembly. By the means of adjusting the weight ratios and concentration ratios of components, stable complexes were formulated with a particle size of 256.8 ± 10.7 nm and zeta potential of 25.1 ± 2.3 mV. Moreover, this DNA vaccine delivery system could achieve specific delivery into DCs, high transfection efficiency and low cytotoxicity, holding great promise for immunotherapy.

Multifunctional Nucleus-targeting Nanoparticles with Ultra-high Gene Transfection Efficiency for In Vivo Gene Therapy

Cancer stem cell-like cells (CSCL) are responsible for tumor recurrence associated with conventional therapy (e.g. surgery, radiation, and chemotherapy). Here, we developed a novel multifunctional nucleus-targeting nanoparticle-based gene delivery system which is capable of targeting and eradicating CSCL. These nanoparticles can facilitate efficient endosomal escape and spontaneously penetrate into nucleus without additional nuclear localization signal. They also induced extremely high gene transfection efficiency (>95%) even in culture medium containing 30% serum, which significantly surpassed that of some commercial transfection reagents, such as Lipofectamine 2000 and Lipofectamine 3000 etc. Especially, when loaded with the TRAIL gene, this system mediated remarkable depletion of CSCL. Upon systemic administration, the nanoparticles accumulated in tumor sites while sparing the non-cancer tissues and significantly inhibited the growth of tumors with no evident systemic toxicity. Taken together, our results suggest that these novel multifunctional, nucleus-targeting nanoparticles are a very promising in vivo gene delivery system capable of targeting CSCL and represent a new treatment candidate for improving the survival of cancer patients.

Highly effective photothermal chemotherapy with pH-responsive polymer-coated drug-loaded melanin-like nanoparticles

Dopamine is a neurotransmitter commonly used in clinical treatment. Polydopamine (PDA) has excellent histocompatibility and biosafety and can efficiently convert near-infrared reflection (NIR) to thermal energy. In this study, PDA was used as a promising carrier, and pH-responsive polymer-coated drug-loaded PDA nanoparticles (NPs; doxorubicin@ poly(allylamine)-citraconic anhydride [Dox@PAH-cit]/PDA NPs) were developed. As expected, the Dox@PAH-cit/PDA NPs exhibited excellent photothermal efficiency. In addition, at a low pH condition, the loaded Dox was released from the NPs due to the amide hydrolysis of PAH-cit. Upon NIR exposure (808 nm), the temperature of the NP solution rapidly increases to kill tumor cells. Compared with unbound chemotherapy drugs, the NPs have a stronger cell uptake ability. In vivo, the PDA NPs were able to efficiently accumulate at the tumor location. After intravenous administration and NIR exposure, tumor growth was significantly inhibited. In summary, the present investigation demonstrated that the Dox@PAH-cit/PDA NPs presented highly effective photothermal chemotherapy for prostate cancer.

Combined bortezomib-based chemotherapy and p53 gene therapy using hollow mesoporous silica nanospheres for p53 mutant non-small cell lung cancer treatment

Hollow mesoporous silica nanospheres (HMSN)-based co-delivery of bortezomib (BTZ) and the tumor suppressor gene p53 was developed for p53 signal impaired NSCLC therapy.

Engineering nanolayered particles for modular drug delivery

Layer-by-layer (LbL) based self-assembly of nanoparticles is an emerging and powerful method to develop multifunctional and tissue responsive nanomedicines for a broad range of diseases. This unique assembly technique is able to confer a high degree of modularity, versatility, and compositional heterogeneity to nanoparticles via the sequential deposition of alternately charged polyelectrolytes onto a colloidal template. LbL assembly can provide added functionality by directly incorporating a range of functional materials within the multilayers including nucleic acids, synthetic polymers, polypeptides, polysaccharides, and functional proteins. These materials can be used to generate hierarchically complex, heterogeneous thin films on an extensive range of both traditional and novel nanoscale colloidal templates, providing the opportunity to engineer highly precise systems capable of performing the numerous tasks required for systemic drug delivery. In this review, we will discuss the recent advancements towards the development of LbL nanoparticles for drug delivery and diagnostic applications, with a special emphasis on the incorporation of biostability, active targeting, desirable drug release kinetics, and combination therapies into LbL nanomaterials. In addition to these topics, we will touch upon the next steps for the translation of these systems towards the clinic.

Liposome-mediated transfection of wild-type P53 DNA into human prostate cancer cells is improved by low-frequency ultrasound combined with microbubbles

Prostate cancer is a common type of cancer in elderly men. The aim of the present study was to evaluate the effects of ultrasound exposure in combination with SonoVue microbubbles on liposome-mediated transfection of wild-type P53 genes into human prostate cancer cells. PC-3 human prostate cancer cells were exposed to ultrasound; duty cycle was controlled at 20% (2 sec on, 8 sec off) for 5 min with and without SonoVue microbubble echo-contrast agent using a digital sonifier (frequency, 21 kHz; intensity, 46 mW/cm²). The cells were divided into eight groups, as follows: Group A (SonoVue + wild-type P53), group B (ultrasound + wild-type P53), group C (SonoVue + ultrasound + wild-type P53), group D (liposome + wild-type P53), group E (liposome + SonoVue + wild-type P53), group F (liposome + wild-type P53 + ultrasound), group G (liposome + wild-type P53 + ultrasound + SonoVue) and the control group (wild-type P53). Following treatment, a hemocytometer was used to measure cell lysis, reverse transcription-quantitative polymerase chain reaction and western blotting were performed to detect P53 gene transfection efficiency, Cell Counting Kit-8 was employed to reveal cell proliferation and Annexin V/propidium iodide staining was used to determine cell apoptosis. Cell lysis was minimal in each group. Wild-type P53 gene and protein expression were significantly increased in the PC-3 cells in group G compared with the control and all other groups (P<0.01). Cell proliferation was significantly suppressed in group G compared with the control group and all other groups (P<0.01). Cell apoptosis levels in group G were significantly improved compared with the control group and all other groups (P<0.01). Thus, the results of the present study indicate that the use of low-frequency and low-energy ultrasound in combination with SonoVue microbubbles may be a potent physical method for increasing liposome gene delivery efficiency.

Quercetin-loaded nanomicelles to circumvent human castration-resistant prostate cancer in vitro and in vivo

Prostate cancer is highly prevalent and has become the second leading cause of cancer-related death in men. Its treatment remains a challenge in the clinic, particularly in patients who have advanced to "castration-resistant prostate cancer" (CRPC). Thus, more effective therapeutic strategies are required. Quercetin (QCT) is a natural flavonoid compound that has attracted increasing interest due to its anticancer activity. However, the clinical application of quercetin is largely hampered by its poor water solubility and low bioavailability. The objective of this study was to evaluate the therapeutic potential of novel QCT-loaded nanomicelles (M-QCTs) assembled from DSPE-PEG2000 for prostate cancer treatment. Our results indicated that QCT was efficiently encapsulated into micelles up to 1 mg mL(-1), which corresponds to a 450-fold increase of its water solubility. In vitro studies showed that the half-maximal inhibitory concentration (IC50) value (20.2 μM) of M-QCTs was much lower than free QCT (>200 μM). Thus, M-QCTs were considerably more effective than free QCT in proliferation inhibition and apoptosis induction of human androgen-independent PC-3 cells. Furthermore, M-QCTs showed superior antitumor efficacy and the tumor proliferation rate reduced by 52.03% compared to the control group in the PC-3 xenograft mouse model, possibly due to increased accumulation of M-QCTs at the tumor site by the enhanced permeability and retention (EPR) effect. Collectively, our studies demonstrated that M-QCTs significantly increase drug accumulation at the tumor site and exhibit superior anticancer activity in prostate cancer. Thus, our nanomicelle-based drug delivery system constitutes a promising and effective therapeutic strategy for clinical treatment.

p53 overexpression increases chemosensitivity in multidrug-resistant osteosarcoma cell lines

PURPOSE

Multidrug resistance (MDR) is a major obstacle to the successful treatment of osteosarcoma with chemotherapy. Effectiveness of cancer therapy correlates with the ability to induce a p53-dependent apoptotic response. p53 is a tumor suppressor gene that is mutated in 22 % of osteosarcomas. While impaired p53 has been implicated in the oncogenesis of osteosarcoma, it is unclear whether overexpression of wild-type p53 can increase chemosensitivity in MDR osteosarcoma cells.

METHODS

We transfected a plasmid encoding the wild-type p53 gene to MDR osteosarcoma cell lines, which have different p53 statuses, U-2OSR2 with wild-type p53 (Wt-p53) and KHOSR2 with mutant p53 (Mt-p53), and determined the effect of p53 overexpression on chemosensitivities.

RESULTS

Both of the U-2OSR2 and KHOSR2 cell lines displayed similar trends in p53-induced drug sensitivities. However, it seems that the impact of p53 overexpression is different based on the differential intrinsic p53 status in these cell lines. In the KHOSR2 cell line (Mt-p53), overexpression of p53 up-regulates the expression of pro-apoptotic protein p21 and Bax, while in the U-2OSR2 cell line (Wt-p53), overexpression of p53 down-regulates IGF-1r expression significantly.

CONCLUSIONS

These results demonstrated that transfection of wild-type p53 increases chemosensitivity either through inhibiting IGF-1r or through increasing the expression of pro-apoptotic proteins p21 and Bax in human MDR osteosarcoma cell lines.

Co-delivery of doxorubicin and tumor-suppressing p53 gene using a POSS-based star-shaped polymer for cancer therapy

In this work, a star-shaped polymer consisting of a cationic poly[2-(dimethylamino) ethyl methacrylate] (PDMAEMA) shell and a zwitterionic poly[N-(3-(methacryloylamino) propyl)-N,N-dimethyl-N-(3-sulfopropyl) ammonium hydroxide] (PMPD) corona was grafted from a polyhedral oligomeric silsesquioxanes (POSS)-based initiator via atomic transfer radical polymerization (ATRP). The reported star-shaped polymer could form stable micelles in aqueous solutions even in the presence of serum. In addition, anti-cancer drug doxorubicin and tumor-suppressing p53 gene were loaded in the process of micelle formation. The formed polyplex was biocompatible and highly efficient for both drug and gene delivery. Furthermore, the polyplex was able to cause a high apoptotic rate of tumor cells both in vitro and in vivo. This combination delivery strategy offers a promising method for cancer therapy and can be used for further clinical applications.