Engineering Transferrin-Decorated Pullulan-Based Prodrug Nanoparticles for Redox Responsive Paclitaxel Delivery to Metastatic Lung Cancer Cells.

Paclitaxel (PTX) remains a cornerstone in the treatment of locally advanced and metastatic lung cancer. To improve its therapeutic indices against lung cancer, novel redox-sensitive pullulan/PTX-based prodrug NPs (PULL-SS-PTX NPs) were accomplished, which were further surface-decorated with transferrin (TF), a cancer cell-targeting ligand, to afford TF-PULL-SS-PTX NPs. These prodrug NPs (drug content, >37% and average size, 134-163 nm) rapidly dismantled their self-assembled architecture upon exposure to simulated reducing conditions, causing a triggered drug release as compared to the control scaffold (PULL-CC-PTX NPs). These scaffolds also evidenced outstanding colloidal stability, cellular uptake efficiency, and discriminating cytotoxicity between the cancer and healthy cells. Intravenously delivered redox-sensitive NPs exhibited improved tumor-suppressing properties as compared to the control nanovesicles (PULL-CC-PTX NPs) in a B16-F10 melanoma lung metastasis mice model. The targeting efficiency and associated augmented anticancer potentials of TF-PULL-SS-PTX NPs relative to TF-free redox-responsive NPs and Taxol intravenous injection were also established on the transferrin receptor (TFR) overexpressed Lewis lung carcinoma (LLC-luc) cell-bearing mice model. Moreover, the TF-functionalized scaffold displayed a reduced systemic toxicity compared to that of Taxol intravenous injection. Overall, the proposed TF-decorated prodrug NPs could be a promising nanomedicine for intracellular PTX delivery against metastatic lung cancer.

Airway epithelial cell-specific delivery of lipid nanoparticles loading siRNA for asthma treatment.

With specific and inherent mRNA cleaving activity, small interfering RNA (siRNA) has been deemed promising therapeutics to reduce the exacerbation rate of asthma by inhibiting the expression and release of proinflammatory cytokines from airway epithelial cells (AECs). To exert the therapeutic effects of siRNA drugs, nano-formulations with high efficiency and safety are required to deliver these nucleic acids to the target cells. Herein, we exploited novel inhaled lipid nanoparticles (LNPs) targeting intercellular adhesion molecule-1 (ICAM-1) receptors on the apical side of AECs. This delivery system is meant to enhance the specific delivery efficiency of siRNA in AECs to prevent the expression of proinflammatory cytokines in AECs and the concomitant symptoms in parallel. A cyclic peptide that resembles part of the capsid protein of rhinovirus and binds to ICAM-1 receptors was initially conjugated with cholesterol and subsequently assembled with ionizable cationic lipids to form the LNPs (Pep-LNPs) loaded with siRNA against thymic stromal lymphopoietin (TSLP siRNA). The obtained Pep-LNPs were subjected to thorough characterization and evaluations in vitro and in vivo. Pep-LNPs significantly enhanced cellular uptake and gene silencing efficiency in human epithelial cells expressing ICAM-1 in vitro, exhibited AEC-specific delivery and improved the gene silencing effect in ovalbumin-challenged asthmatic mice after pulmonary administration. More importantly, Pep-LNPs remarkably downregulated the expression of TSLP in AECs, effectively alleviated inflammatory cell infiltration, and reduced the secretion of other proinflammatory cytokines, including IL-4 and IL-13, as well as mucus production in asthmatic mice. This study demonstrates that Pep-LNPs are safe and efficient to deliver siRNA drugs to asthmatic AECs and could potentially alleviate allergic asthma by inhibiting the overexpression of proinflammatory cytokines in the airway.

Enzalutamide-Induced Upregulation of PCAT6 Promotes Prostate Cancer Neuroendocrine Differentiation by Regulating miR-326/HNRNPA2B1 Axis.

Our previous studies have demonstrated that Enzalutamide-induced upregulation of long non-coding RNA p21 (lncRNA-p21) facilitates prostate cancer (PCa) neuroendocrine differentiation (NED). Given the important role of lncRNAs in PCa pathogenesis, and given that lots of lncRNAs are dys-regulated in neuroendocrine PCa (NEPC) patients, we next explored the biological function and underlying mechanism of lncRNA-PCAT6 (PCAT6) in mediating Enzalutamide-induced NED. The level of PCAT6 in Enzalutamide-treated PCa cells and NEPC samples were assessed using quantitative RT-PCR (qPCR). The effect of PCAT6 on PCa cell proliferation, invasion, and NED was evaluated through CCK-8, transwell, qPCR, western blot analysis, Xenograft mouse model, and in vivo lung metastasis model. We found that PCAT6 was highly expressed in NE-like cells (PC3, DU145, and NCI-H660) compared with androgen-sensitive LNCaP cells. PCAT6 was also highly expressed in NEPC tissues. Enzalutamide treatment resulted in a significant increase of PCAT6 level in a dose- and time-dependent fashion. Functionally, PCAT6 overexpression promoted NED of C4-2 cells, as evidenced by an increased expression of NE markers (NSE, ChgA, and SYP), whereas PCAT6 knockdown in NCI-H661 cells repressed NED. Furthermore, PCAT6 overexpression promoted PCa cell proliferation and invasion in vitro and in vivo. Mechanistically, PCAT6 functioned as competing endogenous (ce) RNA via absorbing miR-326, thus resulting in a de-suppression of Hnrnpa2b1 target gene. The current results demonstrate that PCAT6 acted as a tumor activator in PCa progression by sponging miR-326 and increasing Hnrnpa2b1 expression and that the PCAT6/miR-326/Hnrnpa2b1 signaling might be a new therapeutic target for PCa.

Long Non-coding RNA AFAP1-AS1 Facilitates Prostate Cancer Progression by Regulating miR-15b/IGF1R Axis.

BACKGROUND: Prostate cancer (PCa) is a commonly diagnosed malignant cancer and is the second- highest cause of cancer death in men worldwide. Enzalutamide is the second-generation inhibitor of androgen receptor signaling and is the fundamental drug for the treatment of advanced PCa. However, the disease will eventually progress to metastatic castration-resistant prostate cancer (CRPC) and aggressive neuroendocrine prostate cancer (NEPC) because of androgen-deprivation therapy (ADT) resistance. The aim of the study was to investigate the role of long non-coding RNA (lncRNA) AFAP1-AS1 in ADT resistance. METHODS: Quantitative real-time PCR analysis (qPCR) was used to assess the expression of AFAP1-AS1 in PCa cell lines and tissues. Cell proliferation and invasion were assessed after AFAP1-AS1 knockdown using Cell Counting Kit (CCK)-8 and Transwell assay, respectively. A dual-luciferase reporter gene assay was carried out to validate the regulatory relationship among AFAP1-AS1, microRNA (miR)-15b, and insulin-like growth factor1 receptor (IGF1R). RESULTS: AFAP1-AS1 level was markedly increased in castration-resistant C4-2 cells and NE-like cells (PC3, DU145, and NCI-H660), compared with androgen-sensitive LNCaP cells. Enzalutamide treatment increased the expression of AFAP1-AS1 in vitro and in vivo. Functionally, AFAP1-AS1 knockdown repressed tumor cell proliferation and invasion. Mechanistically, AFAP1-AS1 functioned as an oncogene in PCa through binding to miR-15b and destroying its tumor suppressor function. Finally, we identified that AFAP1-AS1 up-regulated IGF1R expression by competitively binding to miR-15b to de-repress IGF1R. CONCLUSION: AFAP1-AS1 facilitates PCa progression by regulating miR-15b/IGF1R axis, indicating that AFAP1-AS1 may serve as a diagnostic biomarker and therapeutic target for PCa.

FBLN5 is targeted by microRNA­27a­3p and suppresses tumorigenesis and progression in high­grade serous ovarian carcinoma.

High-grade serous ovarian carcinoma (HGSOC) is one of the most lethal gynecological malignancies; however, the precise molecular mechanisms have not been fully characterized. Fibulin­5 (FBLN­5) is an extracellular matrix (ECM) glycoprotein, and plays a crucial role in maintaining the stability of ECM structures, regulating cell proliferation and tumorigenesis. In the present study, the expression of FBLN­5, as determined by western blot analysis and immunohistochemistry, was significantly increased in normal fallopian tube (FT) samples compared with that in HGSOC samples, and decreased FBLN5 expression was associated with unfavorable prognosis of HGSOC. Functional characterization revealed that FBLN5 overexpression significantly inhibited migration, invasion and proliferation abilities of ovarian cancer cells in vitro. Furthermore, micro (mi)RNA­27a­3p (miR­27a­3p) was revealed to be increased in HGSOC, and dual­luciferase reporter assay indicated that miR­27a­3p was functioned as a negative regulator of FBLN5 by directly binding with its 3'­untranslated region. Collectively, FBLN5 expression was associated with prognosis, proliferation, and metastasis in HGSOC. We hypothesized that FBLN5 was targeted by miR­27a­3p and may serve as a biomarker and provide a new therapeutic approach for the treatment of HGSOC.

Correction to: Kallistatin inhibits tumour progression and platinum resistance in high-grade serous ovarian cancer.

The original article [1] contains errors in Fig. 3C, Results and Discussion.

A Novel Androgen-Induced lncRNA FAM83H-AS1 Promotes Prostate Cancer Progression via the miR-15a/CCNE2 Axis.

Prostate cancer (PCa) is one of the most common types of tumors among males worldwide. However, the roles of long noncoding RNAs (lncRNAs) in PCa remain unclear. This study shows that lncRNA FAM83H-AS1 is upregulated in prostate adenocarcinoma, bladder urothelial carcinoma, and kidney renal papillary cell carcinoma samples. Androgen receptor (AR) signaling plays the most important role in PCa tumorigenesis and development. In this study, the results validate that AR signaling is involved in upregulating FAM83H-AS1 expression in PCa cells. Loss-of-function assays demonstrate that FAM83H-AS1 acts as an oncogene in PCa by modulating cell proliferation, cell cycle, and migration. Bioinformatics analysis demonstrates that FAM83H-AS1 is remarkably related to the regulation of the cell cycle and DNA replication through affecting multiple regulators related to these pathways, such as CCNE2. Mechanically, we found that FAM83H-AS1 plays its roles through sponging miR-15a to promote CCNE2 expression. These findings indicate that FAM83H-AS1 is a novel diagnostic and therapeutic marker for PCa.

Kallistatin inhibits tumour progression and platinum resistance in high-grade serous ovarian cancer.

Ovarian cancer is the most lethal gynaecologic malignancy. Although there are various subtypes of ovarian cancer, high-grade serous ovarian cancer (HGSOC) accounts for 70% of ovarian cancer deaths. Chemoresistance is the primary reason for the unfavourable prognosis of HGSOC. Kallistatin (KAL), also known as SERPINA4, is part of the serpin family. Kallistatin has been discovered to exert multiple effects on angiogenesis, inflammation and tumour progression. However, the roles and clinical significance of kallistatin in HGSOC remain unclear. Here, we showed that kallistatin was significantly downregulated in HGSOC compared to normal fallopian tube (FT) tissues. Low expression of kallistatin was associated with unfavourable prognosis and platinum resistance in HGSOC. Overexpression of kallistatin significantly inhibited proliferation and metastasis, and enhanced platinum sensitivity and apoptosis in ovarian cancer cells. Collectively, these findings demonstrate that kallistatin serves as a prognostic predictor and provide a potential therapeutic target for HGSOC.

miR-1303 promotes the proliferation, migration and invasion of prostate cancer cells through regulating the Wnt/ß-catenin pathway by targeting DKK3.

MicroRNA-1303 (miR-1303) is involved in the tumorigenesis and progression of several cancers, and yet the role of miR-1303 in prostate cancer (PCa) and its underlying mechanism are unknown. To explore this issue, the present study aimed to use PCa tissues, cell lines and a PCa-engrafted mouse model to determine the expression and roles of miR-1303 in PCa. Furthermore, a series of experiments were conducted to explore the underlying mechanisms of action of miR-1303 in PCa cells. miR-1303 was demonstrated to be highly expressed in PCa tissues and cell lines. The level of miR-1303 expression was closely associated with higher Gleason scores and a more developed tumor stage in patients with PCa, and patients with higher levels of miR-1303 displayed a reduced overall survival rate. miR-1303 overexpression promoted the proliferation, migration and invasion of PCa cells. In vivo experiments showed that miR-1303 inhibition suppressed the growth of PCa tumors in mice. Additionally, dickkopf Wnt signaling pathway inhibitor 3 (DKK3) was identified as a target of miR-1303. Knockdown of miR-1303 suppressed the proliferation, migration and invasion of PCa cells, increased DKK3 expression, and inhibited the activity of the Wnt/ß-catenin pathway. In conclusion, miR-1303 may promote proliferation, migration and invasion of PCa cells through activating the Wnt/ß-catenin pathway by regulating DKK3 expression. These results indicated that miR-1303 may be considered as a potential biomarker for PCa treatment.