Effect of streptomycin sulphate on the nitrification system in activated sludge: insight into nitrification characteristic, antibiotic resistance gene and microbial community.

Wastewater with residual streptomycin sulphate usually contains high content of ammonia-nitrogen. However, the biological removal process of ammonia-nitrogen under streptomycin sulphate circumstance was unclear. In this study, short-term and long-term effects of streptomycin sulphate on biological nitrification systems, including AOB, NOB, SAOR, SNOR and SNPR, were evaluated comprehensively. The results indicated IC50 for AOB and NOB were 7.5 and 6.6 mg/L. SAOR and SNPR could be decreased to 3.43 ± 0.52 mg N/(g MLSS·h) and 0.24 ± 0.03 mg N/(g MLSS·h) while the addition of streptomycin sulphate was 10 mg/L. When streptomycin sulphate addition was stopped, nitrification ability recovered slightly, SAOR and SNPR increased to 9.37 ± 0.36 mg N/(g MLSS·h) and 1.66 ± 0.49 mg N/(g MLSS·h), respectively. The protein of EPS increased gradually during the acclimatization process, and the maximal protein value was 68.24 mg/g MLSS on the 100th day, however, no significant change of polysaccharose was observed during the acclimatization process. High abundance of ARGs and intI1 was detected in effluent and sludge of the biological treatment system. The maximal relative abundance of aadA1 in the sludge appeared on the 140th day, and increased by 0.99 orders of magnitude. Biological diversity decreased significantly during the acclimatization process, relative abundance of nitrosomonas was changed from 9.07% to 38.68% on the 61st day, while relative abundance of nitrobacter was changed from 1.30% to 0.64%. It should be noted that relative abundances of nitrosomonas and nitrobacter were reduced to 16.17% and 0.25% on the 140th day. This study would be helpful for nitrogen removal in wastewater with antibiotic.

Coordinated modulation of long non-coding RNA ASBEL and curcumin co-delivery through multicomponent nanocomplexes for synchronous triple-negative breast cancer theranostics.

BACKGROUND: Abnormally regulated long non-coding RNAs (lncRNAs) functions in cancer emphasize their potential to serve as potential targets for cancer therapeutic intervention. LncRNA ASBEL has been identified as oncogene and an anti-sense transcript of tumor-suppressor gene of BTG3 in triple-negative breast cancer (TNBC). RESULTS: Herein, multicomponent self-assembled polyelectrolyte nanocomplexes (CANPs) based on the polyelectrolytes of bioactive hyaluronic acid (HA) and chitosan hydrochloride (CS) were designed and prepared for the collaborative modulation of oncogenic lncRNA ASBEL with antago3, an oligonucleotide antagonist targeting lncRNA ASBEL and hydrophobic curcumin (Cur) co-delivery for synergetic TNBC therapy. Antago3 and Cur co-incorporated CANPs were achieved via a one-step assembling strategy with the cooperation of noncovalent electrostatic interactions, hydrogen-bonding, and hydrophobic interactions. Moreover, the multicomponent assembled CANPs were ulteriorly decorated with a near-infrared fluorescence (NIRF) Cy-5.5 dye (FCANPs) for synchronous NIRF imaging and therapy monitoring performance. Resultantly, MDA-MB-231 cells proliferation, migration, and invasion were efficiently inhibited, and the highest apoptosis ratio was induced by FCANPs with coordination patterns. At the molecular level, effective regulation of lncRNA ASBEL/BTG3 and synchronous regulation of Bcl-2 and c-Met pathways could be observed. CONCLUSION: As expected, systemic administration of FCANPs resulted in targeted and preferential accumulation of near-infrared fluorescence signal and Cur in the tumor tissue. More attractively, systemic FCANPs-mediated collaborative modulating lncRNA ASBEL/BTG3 and Cur co-delivery significantly suppressed the MDA-MB-231 xenograft tumor growth, inhibited metastasis and extended survival rate with negligible systemic toxicity. Our present study represented an effective approach to developing a promising theranostic platform for combating TNBC in a combined therapy pattern.

Effects of plant residues on C:N:P of soil, microbial biomass, and extracellular enzyme in an alpine mea-dow on the Qinghai-Tibetan Plateau, China.

Plant residues can affect C:N:P of soil, microbial biomass, and extracellular enzyme, but the effects are still unclear. We conducted a field experiment in an alpine meadow on the eastern part of the Qinghai-Tibetan Plateau to explore the effects of removing aboveground plant or roots and adding plant residues on the C:N:P of soil, microbial biomass, and extracellular enzyme. The results showed that removing aboveground plant biomass significantly decreased soil C:N (the change was -23.7%, the same below) and C:P (-14.7%), microbial biomass C:P and N:P, while significantly increased microbial biomass C:N, and enzyme C:N:P compared with meadow without human disturbance. Removing all plant biomass (aboveground and roots) significantly reduced soil C:N (-11.6%), C:P (-24.0%), N:P (-23.3%) and microbial biomass C:N in comparison to removing aboveground plant, while significantly improved microbial biomass N:P and enzyme N:P. Adding plant residues after removing aboveground plant significantly increased microbial biomass C:N and C:P, enzyme C:N compared with removing aboveground plant, while significantly decreased enzyme N:P. Compared with removing all the plant, adding plant residues after removing whole plant significantly reduced soil C:N (-16.4%), microbial biomass C:P, N:P and enzyme N:P, while significantly increased enzyme C:N. Our results suggest that removal of plants could have a strong effect on C:N:P of soil, microbial biomass, and extracellular enzyme, and C:N:P of microbial biomass and that extracellular enzyme woule be more sensitive to plant residues. Roots could play a key role in stabilizing C:N:P of soil, microbial biomass, and extracellular enzyme under plant residues addition. Adding plant residues could be a suitable solution for restoring alpine meadows under the circumstance of intact roots, which was conducive to soil C storage, but might not be suitable for alpine meadows with serious root damage, which would increase soil CO2 emission.

A multifunctional nanodiamond-based nanoplatform for the enhanced mild-temperature photothermal/chemo combination therapy of triple negative breast cancer via an autophagy regulation strategy.

Owing to its aggressive biological behavior, the lack of specific targets, and the strong therapeutic resistance of triple negative breast cancer (TNBC), current therapeutic strategies are still limited. The combination of multiple treatments has been confirmed as a promising strategy for TNBC therapy. However, the efficacy of combination therapy can be restricted due to increasing therapeutic resistance to various treatments. Herein, we constructed a nanodiamond (ND)-based nanoplatform for augmented mild-temperature photothermal/chemo combination therapy against TNBC, weakening the therapeutic resistance via autophagy inhibition enabled by the NDs. A layer-by-layer self-assembly approach was utilized to construct the ND-based nanoplatform. First, the NDs were modified with protamine sulphate (PS). Meanwhile, the photosensitizer indocyanine green (ICG) and the HSP70 small molecule inhibitor apoptozole (APZ) could be synchronously incorporated to form positively charged PS@ND (ICG + APZ). Then negatively charged hyaluronic acid (HA) was assembled onto the outer face of PS@ND (ICG + APZ) to form the NPIAs. Finally, the positively charged small molecule anti-cancer drug doxorubicin (DOX) could be adsorbed onto the surface of the NPIAs through electrostatic interactions (NPIADs). The resulting NPIADs could be triggered by NIR laser irradiation to exhibit enhanced mild-temperature photothermal therapy (PTT) effects via suppressing the expression of HSP70, and PTT combined with chemotherapy could further enhance the anti-tumor efficacy. Subsequently, the sensitivity of MDA-MB-231 cells could be significantly improved through the weakening of the thermal/drug resistance via autophagy inhibition, leading to augmented combination therapy that is efficient both in vitro and in vivo. Furthermore, the NPIADs could be used as a theranostic nanoplatform for fluorescence (FL) and photoacoustic (PA) imaging. Taken together, this study demonstrated a multifunctional ND-based nanoplatform for FL/PA imaging-guided augmented mild-temperature photothermal/chemo combination therapy via an autophagy regulation strategy against TNBC.

Multicomponent-assembled nanodiamond hybrids for targeted and imaging guided triple-negative breast cancer therapy via a ternary collaborative strategy.

Uniting combinational strategies has been confirmed to be a robust choice for high-performance cancer treatment due to their abilities to overcome tumor heterogeneity and complexity. However, the development of a simple, effective, and multifunctional theranostics nanoplatform still remains a challenge. In this study, we integrated multicomponent hyaluronic acid (HA), protamine (PS), nanodiamonds (NDs), curcumin (Cur), and IR780 into a single nanoplatform (denoted as HPNDIC) based on the combination of hydrophobic and electrostatic noncovalent interactions for dual-modal fluorescence/photoacoustic imaging guided ternary collaborative Cur/photothermal/photodynamic combination therapy of triple-negative breast cancer (TNBC). A two-step coordination assembly strategy was utilized to realize this purpose. In the first step, PS was utilized to modify the NDs clusters to form positively charged PS@NDs (PND) and the simultaneous encapsulation of the natural small-molecule drug Cur and the photosensitive small-molecule IR780 (PNDIC). Second, HA was adsorbed onto the outer surface of the PNDIC through charge complexation for endowing a tumor-targeting ability (HPNDIC). The resulting HPNDIC had a uniform size, high drug-loading ability, and excellent colloidal stability. It was found that under the near-infrared irradiation condition, IR780 could be triggered to exhibit both PTT/PDT dual-pattern therapy effects, leading to an enhanced therapy efficiency of Cur both in vitro and in vivo with good biocompatibility. Due to the intrinsic imaging property of IR780, the biodistribution and accumulation behavior of HPNDIC in vivo could be monitored by dual-modal fluorescence/photoacoustic imaging. Taken together, our current work demonstrated the assembly of a NDs-based multicomponent theranostic platform for dual-modal fluorescence/photoacoustic imaging guided triple-collaborative Cur/photothermal/photodynamic against TNBC.

Apoptotic Effect of 1800 MHz Electromagnetic Radiation on NIH/3T3 Cells.

To investigate the effect of 1800 MHz electromagnetic radiation (EMR) on apoptosis, we exposed NIH/3T3 cells at 1800 MHz with a specific absorption rate (SAR) of 2 W/kg intermittently for 12, 24, 36, and 48 h. After exposure, Cell Counting Kit-8 (CCK-8) and flow cytometry were used to detect cell viability and apoptosis; the expression of p53, a molecule with the key role in apoptosis, was measured by real-time qPCR, western blot, and immunofluorescence; and images of the structure of the mitochondria, directly reflecting apoptosis, were captured by electron microscopy. The results showed that the viability of cells in the 12, 36, and 48 h exposure groups significantly decreased compared with the sham groups; after 48 h of exposure, the percentage of late apoptotic cells in the exposure group was significantly higher. Real-time qPCR results showed that p53 mRNA in the 48 h exposure group was 1.4-fold of that in the sham group; significant differences of p53 protein fluorescence expression were observed between the exposure groups and the sham groups after 24 h and 48 h. The mitochondrial swelling and vesicular morphology were found in the electron microscopy images after 48 h exposure. These findings demonstrated 1800 MHz, SAR 2 W/kg EMR for 48 h may cause apoptosis in NIH/3T3 cells and that this apoptosis might be attributed to mitochondrial damage and upregulation of p53 expression.

Self-assembled nanovehicle-mediated co-encapsulation of inactivated EV71 virus and CpG oligonucleotides elicits potent anti-EV71 humoral and cellular immune protective responses.

Inactivated vaccines are widely used for prevention of viral disease. Both humoral and cellular immune responses have been shown to play important roles in the control and clearance of virus infections. CpG motif containing oligodeoxynucleotides (ODN) have recently gained considerable interest and been used as vaccine adjuvant due to their potent abilities to modulate host immune response. In this study, CpG-ODN adjuvant and inactivated viral particles of enterovirus 71 (EV71) were co-encapsulated into nanoparticles (NP) generated by using protamine sulfate (PS) and carboxymethyl ß-glucan (CMG) through a self-assembly approach. The administration of EV71 nanovaccine elicited not only specific anti-EV71 neutralizing antibody response, but also cellular immune response characterized by strong productions of IFN-α and IFN-γ. The results suggest that CMG/PS-based nanovehicles hold a great potential to be a novel platform for nanovaccine development against viral disease.

Recombinant DENV 2 NS5: An effective antigen for diagnosis of DENV infection.

Dengue fever is a mosquito-borne viral disease with dramatically increasing morbidity rate worldwide in decades. Since there is no specific treatment to date, early diagnosis is important for providing proper timely medical care to minimize mortality, and for the prompt initiation of public health control measures. NS5 is a potential biomarker for dengue virus infection due to its highly conserved and immunogenic properties. In this study, the DENV 2 NS5 full-length and the DENV 2 NS5 C-terminus RNA-dependent RNA polymerase domain fragment (NS5-C70) expression plasmids were constructed, and the 104 kDa full-length NS5 and the 70 kDa NS5-C70 were respectively expressed in Escherichia coli. These two purified recombinant products were found to react with the sera of patients infected with dengue virus when analyzed by an enzyme-linked immunosorbent assay (ELISA), which resulted in significantly higher absorption values than those of control sera. The recombinant DENV 2 NS5 exhibited strong reactivity to each of the four types of sera, whereas the NS5-C70 showed strong reactivity only to DENV 2 and 4. In comparison, the positive agreement value of recombinant NS5-based assay with either MyBioSource or Panbio assay was higher than that of the two commercially available IgG indirect ELISA kits. These results suggest that the recombinant DENV 2 NS5 be an effective antigen for detection of dengue virus infection. The recombinant NS5-C70 may also be used as an auxiliary antigen for diagnostic purposes.

Nanodiamond-based layer-by-layer nanohybrids mediate targeted delivery of miR-34a for triple negative breast cancer therapy.

Triple-negative breast cancer (TNBC) is the most lethal subtype of breast cancer and significantly associated with poor prognosis and high risk of recurrence. miR-34a has been identified as a potent tumor suppressor whose expression is dramatically downregulated in TNBC. Currently, rectification of miRNA abnormality serves as a novel tumor therapeutic strategy. miR-34a is thus used as powerful antitumor agent for miRNA-based therapy against TNBC. However, miRNA-based antitumor therapy is challenged by effective targeted delivery of miRNA. In the present study, nanodiamond (ND), protamine (PS) and folic acid (FA) were used to construct ND-based layer-by-layer nanohybrids through a self-assembly approach for targeted miR-34a delivery in TNBC cells and xenograft TNBC tumors. We found that the targeted delivery of miR-34a remarkably suppressed cell proliferation, migration and induced the apoptosis of TNBC cells in vitro and inhibited tumor growth in vivo via down-regulating Fra-1 expression. The data suggest a great potential of ND-based nanohybrids for targeted intratumoral delivery of miR-34a for TNBC therapy.

Targeting long non-coding RNA ASBEL with oligonucleotide antagonist for breast cancer therapy.

Long non-coding RNAs (lncRNAs) are defined as a class of RNA transcripts longer than 200 nucleotides encoded by mammalian genomes that lack protein-coding potential. LncRNA ASBEL has been identified as an anti-sense transcript of BTG3 (B cell translocation gene 3) gene, which encodes an anti-proliferation protein. Remarkable down-regulation of BTG3 has been reported in triple-negative breast cancer (TNBC). In the present study, a number of single-stranded modified anti-sense DNA oligonucleotides (antago) were designed, synthesized and screened for specific lncRNA ASBEL knockdown. We showed here that anti-ASBEL antago played a significant tumor suppressive role in TNBC by effective down-regulating lncRNA ASBEL, which in turn led to increased BTG3 expression. The obtained data suggest lncRNA ASBEL as a novel therapeutic target in TNBC.

miR-100 suppresses the proliferation and tumor growth of esophageal squamous cancer cells via targeting CXCR7.

MicroRNAs are highly conserved non-coding RNAs that regulate gene expression at the post-transcriptional level, and play pivotal roles in cancer development and progression. miR-100 has been reported to be significantly downregulated in a variety of cancers, including esophageal cancer. However, the role of miR-100 in human esophageal cancer has not been fully elucidated. We demonstrated that overexpression of miR-100 in esophageal cancer cells markedly inhibited cell proliferation, migration and invasion as well as tumor growth. We subsequently showed that CXCR7 is a direct target gene of miR-100. Our results indicated that miR-100 plays a tumor-suppressor role in esophageal cancer and suggest its potential application for esophageal cancer treatment.

C3-Luc Cells Are an Excellent Model for Evaluation of Cellular Immunity following HPV16L1 Vaccination.

C3 and TC-1 are the two model cell lines most commonly used in studies of vaccines and drugs against human papillomavirus (HPV) infection. Because C3 cells contain both the HPV16 E and L genes, but TC-1 cells contain only the HPV16 E genes, C3 cells are usually used as the model cell line in studies targeting the HPV16 L protein. However, expression of the L1 protein is difficult to detect in C3 cells using common methods. In our study, Short tandem repeat analysis (STR) was used to demonstrate that C3 cells are indeed derived from mice, PCR results show that HPV16 L1, E6 and E7 genes were detected in C3 genomic DNA, and RT-PCR results demonstrated that L1 transcription had occurred in C3 cells. However, the expression of C3 protein was not found in the results of western blot and immunohistochemistry (IHC). Growth and proliferation of C3 were inhibited by mice spleen lymphocytes that had been immunized with a vaccine against HPV16L1. The luciferase gene was integrated into C3 cells, and it was confirmed that addition of the exogenous gene had no effect on C3 cells by comparing cell growth and tumor formation with untransformed cells. Cells stably expressing luciferase (C3-luc) were screened and subcutaneously injected into the mice. Tumors became established and were observed using a Spectrum Pre-clinical in Vivo Imaging System. Tumor size of mice in the different groups at various time points was calculated by counting photons. The sensitivity of the animals to the vaccine was quantified by statistical comparison. Ten or 30 days following injection of the C3-luc cells, tumor size differed significantly between the PBS and vaccine groups, indicating that C3 cells were susceptible to vaccination even after tumors were formed in vivo.

One-prime multi-boost strategy immunization with recombinant DNA, adenovirus, and MVA vector vaccines expressing HPV16 L1 induces potent, sustained, and specific immune response in mice.

Human papillomavirus (HPV) is associated with various human diseases, including cancer, and developing vaccines is a cost-efficient strategy to prevent HPV-related disease. The major capsid protein L1, which an increasing number of studies have confirmed is typically expressed early in infection, is a promising antigen for such a vaccine, although the E6 and E7 proteins have been characterized more extensively. Thus, the L1 gene from HPV16 was inserted into a recombinant vector, AdHu5, and MVA viral vectors, and administered by prime-boost immunization. Virus-like particles were used as control antigens. Our results indicate that prime-boost immunization with heterologous vaccines induced robust and sustained cellular and humoral response specific to HPV16 L1. In particular, sera obtained from mice immunized with DNA + DNA + Ad + MVA had excellent antitumor activity in vivo. However, the data also confirm that virus-like particles can only elicit low levels cellular immunity and not be long-lasting, and are therefore unsuitable for treatment of existing HPV infections.

EV71 virus-like particles produced by co-expression of capsid proteins in yeast cells elicit humoral protective response against EV71 lethal challenge.

BACKGROUND: Enterovirus 71 (EV71) is the most common causative pathogens of hand, foot and mouth disease (HFMD) associated with severe neurological complications. There is a great need to develop prophylactic vaccine against EV71 infection. RESULTS: EV71 virus-like particle (VLP) was produced in yeast expression system by the co-expression of four EV71 structural proteins VP1-VP4. Immunization with the recombinant VLPs elicited potent anti-EV71 antibody responses in adult mice and anti-VLP sera were able to neutralize EV71 virus in vitro. Neonatal mice model demonstrated VLP immunization conferred protection to suckling mice against the lethal viral challenge. CONCLUSIONS: Co-expression of four EV71 structural proteins VP1-VP4 in yeast expression systems is an effective method to produce EV71 VLPs. VLP-based vaccine shows great potential to prevent EV71 infection.

Transient Tear Film Dysfunction after Cataract Surgery in Diabetic Patients.

PURPOSE: Diabetes mellitus is an increasingly common systemic disease. Many diabetic patients seek cataract surgery for a better visual acuity. Unlike in the general population, the influence of cataract surgery on tear film function in diabetic patients remains elusive. The aim of this study was to evaluate the tear function in diabetic and nondiabetic patients following cataract surgery. METHODS: In this prospective, interventional case series, 174 diabetic patients without dry eye syndrome (DES) and 474 age-matched nondiabetic patients as control who underwent phacoemulsification were enrolled at two different eye centers between January 2011 and January 2013. Patients were followed up at baseline and at 7 days, 1 month, and 3 months postoperatively. Ocular symptom scores (Ocular Surface Disease Index, OSDI) and tear film function including tear film stability (tear film break-up time, TBUT), corneal epithelium integrity (corneal fluorescein staining, CFS), and tear secretion (Schirmer's I test, SIT) were evaluated. RESULTS: In total, 83.9% of the diabetic patients (146 cases with 185 eyes) and 89.0% of the nondiabetic patients (422 cases with 463 eyes) completed all check-ups after the interventions (P = 0.095). The incidence of DES was 17.1% in the diabetic patients and 8.1% in the nondiabetic patients at 7 days after cataract surgery. In the diabetic patients, the incidence of DES remained 4.8% at 1 month postoperatively and decreased to zero at 3 months after surgery. No DES was diagnosed in nondiabetic patients at either the 1-month or 3-month follow-up. Compared with the baseline, the diabetic patients had worse symptom scores and lower TBUT values at 7 days and 1 month but not at 3 months postoperatively. In the nondiabetic patients, symptom scores and TBUT values had returned to preoperative levels at 1-month check-up. CFS scores and SIT values did not change significantly postoperatively in either group (P = 0.916 and P = 0.964, respectively). CONCLUSIONS: Diabetic patients undergoing cataract surgery are prone to DES. Ocular symptoms and tear film stability are transiently worsened in diabetic patients and are restored more slowly than those in nondiabetic patients.

Acidic pH-induced charge-reversal nanoparticles for accelerated endosomal escape and enhanced microRNA modulation in cancer cells.

pH-Induced charge-reversal nanoparticles incorporating microRNA (miRNA) were engineered through a single-step self-assembly of polyelectrolyte complexes. We found that the endosomal/lysosomal acidic environment could trigger the charge reversal of the nanoparticles from negative charge to positive charge and induce the structure alteration of the nanoparticles, which in turn led to accelerated endosomal escape and enhanced miRNA modulation in esophageal cancer cells.

Phage Display-Derived Cross-Reactive Neutralizing Antibody against Enterovirus 71 and Coxsackievirus A16.

Enterovirus 71 (EV71) and coxsackievirus A16 (CVA16) are members of the Picornaviridae family and are considered the main causative agents of hand, foot and mouth disease (HFMD). In recent decades large HFMD outbreaks caused by EV71 and CVA16 have become significant public health concerns in the Asia-Pacific region. Vaccines and antiviral drugs are unavailable to prevent EV71 and CVA16 infection. In the current study, a chimeric antibody targeting a highly conserved peptide in the EV71 VP4 protein was isolated by using a phage display technique. The antibody showed cross-neutralizing capability against EV71 and CVA16 in vitro. The results suggest that this phage display-derived antibody will have great potential as a broad neutralizing antibody against EV71 and CVA16 after affinity maturation and humanization.

Design, synthesis and biological evaluation of quinoxalin-2(1H)-one derivatives as EGFR tyrosine kinase inhibitors.

With the successful use of gefitinib and erlotinib in clinic, some potent EGFR tyrosine kinase receptor inhibitors have gained widespread concern in the treatment of ovarian or non-small-cell lung cancer. However, the emergence of EGFR-activating mutations resist to the drugs, there is an impending need to design new inhibitor targeted EGFR. Furthermore, the understanding of mutual effect between EGFR and drug has been available, it has become a hot spot for the research of anticancer drugs. We have designed and synthesized a series of 6-methoxy-7-(3-morpholinopropoxy)-1-(2- phenoxyethyl)-quinoxalin-2(1H)-one derivatives as novel EGFR inhibitors. Most of the compounds have showed inhibitory activity toward EGFR kinase. This work has demonstrated it is possible to construct a new type of EGFR protein kinase inhibitor using a designin strategy.

Degradable hyaluronic acid/protamine sulfate interpolyelectrolyte complexes as miRNA-delivery nanocapsules for triple-negative breast cancer therapy.

Metastatic relapse is a leading cause of cancer-associated death and one of the major obstacles for effective therapy against triple-negative breast cancer. To address this problem, a miRNA-delivering nanocapsule technology based on hyaluronic acid (HA)/protamine sulfate (PS) interpolyelectrolyte complexes (HP-IPECs) is developed for efficient encapsulation and intracellular delivery microRNA-34a (miR-34a), which is a potent endogenous tumor suppressor of breast cancer. The nanocapsules are successfully generated through a self-assembly approach mediated by an electrostatic interaction. In vitro and in vivo experiments illustrate that miR-34a can be efficiently encapsulated into HP-IPECs and delivered into breast cancer cells or breast cancer tissues. Nanocomplex-assisted delivery of miR-34a induces cell apoptosis and suppresses migration, proliferation, and tumor growth of breast cancer cells via targeting CD44 and a Notch-1-signaling pathway. The obtained results suggest that HP-IPECs have a great potential as a biodegradable vector for microRNA-based therapy against triple-negative breast cancer.

Hyaluronic acid-chitosan nanoparticles for co-delivery of MiR-34a and doxorubicin in therapy against triple negative breast cancer.

Metastatic relapse, development of drug resistance in cancer cells and adverse side effects of chemotherapeutic agents are the major obstacles for effective chemotherapy against triple-negative breast cancer. To address these problems, miR-34a, a potent endogenous tumor suppressive molecule in breast cancer, was co-encapsulated with doxorubicin (DOX) into hyaluronic acid (HA)-chitosan (CS) nanoparticles (NPs) and simultaneously delivered into breast cancer cells for improved therapeutic effects of drug. DOX-miR-34a co-loaded HA-CS NPs were successfully prepared through ionotropic gelation method in water. In vitro and in vivo experiments showed that miR-34a and DOX can be efficiently encapsulated into HA-CS NPs and delivered into tumor cells or tumor tissues and enhance anti-tumor effects of DOX by suppressing the expression of non-pump resistance and anti-apoptosis proto-oncogene Bcl-2. In addition, intracellular restoration of miR-34a inhibited breast cancer cell migration via targeting Notch-1 signaling. The obtained data suggest that co-delivery of DOX and miR-34a could achieve synergistic effects on tumor suppression and nanosystem-based co-delivery of tumor suppressive miRNAs and chemotherapeutic agents may be a promising combined therapeutic strategy for enhanced anti-tumor therapy.