Cancer cell-specific and pro-apoptotic SMAC peptide-doxorubicin conjugated prodrug encapsulated aposomes for synergistic cancer immunotherapy.

BACKGROUND: Immunogenic cell death (ICD) is a crucial approach to turn immunosuppressive tumor microenvironment (ITM) into immune-responsive milieu and improve the response rate of immune checkpoint blockade (ICB) therapy. However, cancer cells show resistance to ICD-inducing chemotherapeutic drugs, and non-specific toxicity of those drugs against immune cells reduce the immunotherapy efficiency. METHODS: Herein, we propose cancer cell-specific and pro-apoptotic liposomes (Aposomes) encapsulating second mitochondria-derived activator of caspases mimetic peptide (SMAC-P)-doxorubicin (DOX) conjugated prodrug to potentiate combinational ICB therapy with ICD. The SMAC-P (AVPIAQ) with cathepsin B-cleavable peptide (FRRG) was directly conjugated to DOX, and the resulting SMAC-P-FRRG-DOX prodrug was encapsulated into PEGylated liposomes. RESULTS: The SMAC-P-FRRG-DOX encapsulated PEGylated liposomes (Aposomes) form a stable nanostructure with an average diameter of 109.1 ± 5.14 nm and promote the apoptotic cell death mainly in cathepsin B-overexpressed cancer cells. Therefore, Aposomes induce a potent ICD in targeted cancer cells in synergy of SMAC-P with DOX in cultured cells. In colon tumor models, Aposomes efficiently accumulate in targeted tumor tissues via enhanced permeability and retention (EPR) effect and release the encapsulated prodrug of SMAC-P-FRRG-DOX, which is subsequently cleaved to SMAC-P and DOX in cancer cells. Importantly, the synergistic activity of inhibitors of apoptosis proteins (IAPs)-inhibitory SMAC-P sensitizing the effects of DOX induces a potent ICD in the cancer cells to promote dendritic cell (DC) maturation and stimulate T cell proliferation and activation, turning ITM into immune-responsive milieu. CONCLUSIONS: Eventually, the combination of Aposomes with anti-PD-L1 antibody results in a high rate of complete tumor regression (CR: 80%) and also prevent the tumor recurrence by immunological memory established during treatments.

Hyaluronic acid-bilirubin nanomedicine for targeted modulation of dysregulated intestinal barrier, microbiome and immune responses in colitis.

While conventional approaches for inflammatory bowel diseases mainly focus on suppressing hyperactive immune responses, it remains unclear how to address disrupted intestinal barriers, dysbiosis of the gut commensal microbiota and dysregulated mucosal immune responses in inflammatory bowel diseases. Moreover, immunosuppressive agents can cause off-target systemic side effects and complications. Here, we report the development of hyaluronic acid-bilirubin nanomedicine (HABN) that accumulates in inflamed colonic epithelium and restores the epithelium barriers in a murine model of acute colitis. Surprisingly, HABN also modulates the gut microbiota, increasing the overall richness and diversity and markedly augmenting the abundance of Akkermansia muciniphila and Clostridium XIVα, which are microorganisms with crucial roles in gut homeostasis. Importantly, HABN associated with pro-inflammatory macrophages, regulated innate immune responses and exerted potent therapeutic efficacy against colitis. Our work sheds light on the impact of nanotherapeutics on gut homeostasis, microbiome and innate immune responses for the treatment of inflammatory diseases.

Prevalence and Duration of Acute Loss of Smell or Taste in COVID-19 Patients.

Initially, acute loss of smell (anosmia) and taste (ageusia) was not considered important symptoms for coronavirus disease 2019 (COVID-19). To determine the prevalence of these symptoms and to evaluate their diagnostic significance, we (approximately 150 physicians of the Daegu Medical Association) prospectively collected data of cases of anosmia and ageusia from March 8, 2020, via telephone interview among 3,191 patients in Daegu, Korea. Acute anosmia or ageusia was observed in 15.3% (488/3,191) patients in the early stage of COVID-19 and in 15.7% (367/2,342) patients with asymptomatic-to-mild disease severity. Their prevalence was significantly more common among females and younger individuals (P = 0.01 and P < 0.001, respectively). Most patients with anosmia or ageusia recovered within 3 weeks. The median time to recovery was 7 days for both symptoms. Anosmia and ageusia seem to be part of important symptoms and clues for the diagnosis of COVID-19, particularly in the early stage of the disease.

Interdigitated and Wave-Shaped Electrode-Based Capacitance Sensor for Monitoring Antibiotic Effects.

Label-free and real-time monitoring of the bacterial viability is essential for the accurate and sensitive characterization of the antibiotic effects. In the present study, we investigated the feasibility of the interdigitated and wave-shaped electrode (IWE) for monitoring the effect of tetracycline or kanamycin on Staphylococcus aureus (S. aureus) and methicillin-resistant S.aureus (MRSA). The electrical impedance spectra of the IWE immersed in the culture media for bacterial growth were characterized in a frequency range of 10 Hz to 1 kHz. The capacitance index (CI) (capacitance change relevant with the bacterial viability) was used to monitor the antibiotic effects on the S. aureus and MRSA in comparison to the traditional methods (disk diffusion test and optical density (OD) measurement). The experimental results showed that the percentage of change in CI (PCI) for the antibiotic effect on MRSA was increased by 51.58% and 57.83% in kanamycin and control, respectively. In contrast, the PCI value decreased by 0.25% for tetracycline, decreased by 52.63% and 37.66% in the cases of tetracycline and kanamycin-treated S. aureus, and increased 2.79% in the control, respectively. This study demonstrated the feasibility of the IWE-based capacitance sensor for the label-free and real-time monitoring of the antibiotic effects on S.aureus and MRSA.

Antibody-Assisted Delivery of a Peptide-Drug Conjugate for Targeted Cancer Therapy.

A number of cancer-targeting peptide-drug conjugates (PDCs) have been explored as alternatives to antibody-drug conjugates (ADCs) for targeted cancer therapy. However, the much shorter circulation half-life of PDCs compared with ADCs in vivo has limited their therapeutic value and thus their translation into the clinic, highlighting the need to develop new approaches for extending the half-life of PDCs. Here, we report a new strategy for targeted cancer therapy of a PDC based on a molecular hybrid between an antihapten antibody and a hapten-labeled PDC. An anticotinine antibody (Abcot) was used as a model antihapten antibody. The anticancer drug SN38 was linked to a cotinine-labeled aptide specific to extra domain B of fibronectin (cot-APTEDB), yielding the model PDC, cot-APTEDB-SN38. The cotinine-labeled PDC showed specific binding to and cytotoxicity toward an EDB-overexpressing human glioblastoma cell line (U87MG) and also formed a hybrid complex (HC) with Abcot in situ, designated HC[cot-APTEDB-SN38/Abcot]. In glioblastoma-bearing mice, in situ HC[cot-APTEDB-SN38/Abcot] significantly extended the circulation half-life of cot-APTEDB-SN38 in blood, and it enhanced accumulation and penetration within the tumor and, ultimately, inhibition of tumor growth. These findings suggest that the present platform holds promise as a new, targeted delivery strategy for PDCs in anticancer therapy.

A Hybrid Platform Based on a Bispecific Peptide-Antibody Complex for Targeted Cancer Therapy.

Peptide-based therapeutics have suffered from a short plasma half-life. On the other hand, antibodies suffer from poor penetration into solid tumors owing to their large size. Herein, we present a new molecular form, namely a hybrid complex between a hapten-labeled bispecific peptide and an anti-hapten antibody ("HyPEP-body"), that may be able to overcome the aforementioned limitation. The bispecific peptide containing a cotinine tag was synthesized by linking a peptide specific to fibronectin extra domain B (EDB) and a peptide able to bind and inhibit vascular endothelial growth factor (VEGF), yielding cot-biPEPEDB-VEGF . Simple mixing of cot-biPEPEDB-VEGF and anti-cotinine antibody (Abcot ) yielded the hybrid complex, HyPEPEDB-VEGF . HyPEPEDB-VEGF retained the characteristics of the included peptides, and showed improved pharmacokinetic behavior. Moreover, HyPEPEDB-VEGF showed tumor growth inhibition with excellent tumor accumulation and penetration. These findings suggest that the hybrid platform described here offers a solution for most peptide therapeutics that suffer from a short circulation half-life in blood.

Bilirubin Nanoparticle-Assisted Delivery of a Small Molecule-Drug Conjugate for Targeted Cancer Therapy.

Despite growing interest in targeted cancer therapy with small molecule drug conjugates (SMDCs), the short half-life of these conjugates in blood associated with their small size has limited their efficacy in cancer therapy. In this report, we propose a new approach for improving the antitumor efficacy of SMDCs based on nanoparticle-assisted delivery. Ideally, a nanoparticle-based delivery vehicle would prolong the half-life of an SMDC in blood and then release it in response to stimuli in the tumor microenvironment (TME). In this study, PEGylated bilirubin-based nanoparticles (BRNPs) were chosen as an appropriate delivery carrier because of their ability to release drugs in response to TME-associated reactive oxygen species (ROS) through rapid particle disruption. As a model SMDC, ACUPA-SN38 was synthesized by linking the prostate-specific membrane antigen (PSMA)-targeting ligand, ACUPA, to the chemotherapeutic agent, SN38. ACUPA-SN38 was loaded into BRNPs using a film-formation and rehydration method. The resulting ACUPA-SN38@BRNPs exhibited ROS-mediated particle disruption and rapid release of the SMDC, resulting in greater cytotoxicity toward PSMA-overexpressing prostate cancer cells (LNCaP) than toward ROS-unresponsive ACUPA-SN38@Liposomes. In a pharmacokinetic study, the circulation time of ACUPA-SN38@BRNPs in blood was prolonged by approximately 2-fold compared with that of the SMDC-based micellar nanoparticles. Finally, ACUPA-SN38@BRNPs showed greater antitumor efficacy in a PSMA-overexpressing human prostate xenograft tumor model than SN38@BRNPs or the SMDC alone. Collectively, these findings suggest that BRNPs are a viable delivery carrier option for various cancer-targeting SMDCs that suffer from short circulation half-life and limited therapeutic efficacy.

Black Pigment Gallstone Inspired Platinum-Chelated Bilirubin Nanoparticles for Combined Photoacoustic Imaging and Photothermal Therapy of Cancers.

Bilirubin (BR), a bile pigment that exerts potent antioxidant and anti-inflammatory effects, is also a major constituent of black pigment gallstones found in bile ducts under certain pathological conditions. Inspired by the intrinsic metal-chelating power of BR found in gallstones, herein we report a cisplatin-chelated BR-based nanoparticle (cisPt@BRNP) for use as a new photonic nanomedicine for combined photoacoustic imaging and photothermal therapy of cancers. The cisPt@BRNPs were prepared by simply mixing cisplatin with BRNPs, yielding ca. 150-nm-size NPs. Upon near-IR laser irradiation at 808 nm, cisPt@BRNPs generated considerable heat and induced clear death of cancer cells in vitro. Following intravenous injection into human colon cancer-bearing mice, cisPt@BRNPs allowed effective tumor visualization by photoacoustic imaging and remarkable antitumor efficacy by photothermal therapy, suggesting their potential for use as a new photonic nanomedicine for cancer therapy.

Self-assembled nanoparticles comprising aptide-SN38 conjugates for use in targeted cancer therapy.

Self-assembled nanoparticles (NPs) have been intensively utilized as cancer drug delivery carriers because hydrophobic anticancer drugs may be efficiently loaded into the particle cores. In this study, we synthesized and evaluated the therapeutic index of self-assembled NPs chemically conjugated to a fibronectin extra domain B-specific peptide (APTEDB) and an anticancer agent SN38. The APTEDB-SN38 formed self-assembled structures with a diameter of 58 ± 3 nm in an aqueous solution and displayed excellent drug loading, solubility, and stability properties. A pharmacokinetic study revealed that the blood circulation half-life of SN38 following injection of the APTEDB-SN38 NPs was markedly higher than that of the small molecule CPT-11. The APTEDB-SN38 NPs delivered SN38 to tumor sites by both passive and active targeting. Finally, the APTEDB-SN38 NPs exhibited potent antitumor activities and low toxicities against EDB-expressing tumors (LLC, U87MG) in mice. This system merits further preclinical and clinical investigations for SN38 delivery.

Multistimuli-Responsive Bilirubin Nanoparticles for Anticancer Therapy.

Although stimuli-responsive materials hold potential for use as drug-delivery carriers for treating cancers, their clinical translation has been limited. Ideally, materials used for the purpose should be biocompatible and nontoxic, provide "on-demand" drug release in response to internal or external stimuli, allow large-scale manufacturing, and exhibit intrinsic anticancer efficacy. We present multistimuli-responsive nanoparticles formed from bilirubin, a potent endogenous antioxidant that possesses intrinsic anticancer and anti-inflammatory activity. Exposure of the bilirubin nanoparticles (BRNPs) to either reactive oxygen species (ROS) or external laser light causes rapid disruption of the BRNP nanostructure as a result of a switch in bilirubin solubility, thereby releasing encapsulated drugs. In a xenograft tumor model, BRNPs loaded with the anticancer drug doxorubicin (DOX@BRNPs), when combined with laser irradiation of 650 nm, significantly inhibited tumor growth. This study suggests that BRNPs may be used as a drug-delivery carrier as well as a companion medicine for effectively treating cancers.

Bilirubin Nanoparticles as a Nanomedicine for Anti-inflammation Therapy.

Despite the high potency of bilirubin as an endogenous anti-inflammatory compound, its clinical translation has been hampered because of its insolubility in water. Bilirubin-based nanoparticles that may overcome this critical issue are presented. A polyethylene glycol compound (PEG) was covalently attached to bilirubin, yielding PEGylated bilirubin (PEG-BR). The PEG-BR self-assembled into nanoscale particles with a size of approximately 110 nm, termed bilirubin nanoparticles (BRNPs). BRNPs are highly efficient hydrogen peroxide scavengers, thereby protecting cells from H2 O2 -induced cytotoxicity. In a murine model of ulcerative colitis, intravenous injection of BRNPs showed preferential accumulation of nanoparticles at the sites of inflammation and significantly inhibited the progression of acute inflammation in the colon. Taken together, BRNPs show potential for use as a therapeutic nanomedicine in various inflammatory diseases.

Conversion of low-affinity peptides to high-affinity peptide binders by using a ß-hairpin scaffold-assisted approach.

Affinity maturation of protein-targeting peptides is generally accomplished by homo- or heterodimerization of known peptides. However, applying a heterodimerization approach is difficult because it is not clear a priori what length or type of linker is required for cooperative binding to a target. Thus, an efficient and simple affinity maturation method for converting low-affinity peptides into high-affinity peptides would clearly be advantageous for advancing peptide-based therapeutics. Here, we describe the development of a novel affinity maturation method based on a robust ß-hairpin scaffold and combinatorial phage-display technology. With this strategy, we were able to increase the affinity of existing peptides by more than four orders of magnitude. Taken together, our data demonstrate that this scaffold-assisted approach is highly efficient and effective in generating high-affinity peptides from their low-affinity counterparts.

Complete genome sequences of Klebsiella pneumoniae bacteriophages YMR1 and YMR2 isolated from sewage.

Two Klebsiella pneumoniae bacteriophages, YMR1 and YMR2, which form plaques with halos, were isolated from sewage in Seoul, South Korea. YMR1 and YMR2 have double-stranded DNA genomes of 40,338 bp and 40,756 bp with 49 and 52 predicted protein-coding genes, respectively. Both are predicted to be members of the family Autographiviridae.

Hyaluronic Acid-Bilirubin Nanoparticles as a Tumor Microenvironment Reactive Oxygen Species-Responsive Nanomedicine for Targeted Cancer Therapy.

Introduction: The tumor microenvironment (TME) has attracted considerable attention as a potential therapeutic target for cancer. High levels of reactive oxygen species (ROS) in the TME may act as a stimulus for drug release. In this study, we have developed ROS-responsive hyaluronic acid-bilirubin nanoparticles (HABN) loaded with doxorubicin (DOX@HABN) for the specific delivery and release of DOX in tumor tissue. The hyaluronic acid shell of the nanoparticles acts as an active targeting ligand that can specifically bind to CD44-overexpressing tumors. The bilirubin core has intrinsic anti-cancer activity and ROS-responsive solubility change properties. Methods & Results: DOX@HABN showed the HA shell-mediated targeting ability, ROS-responsive disruption leading to ROS-mediated drug release, and synergistic anti-cancer activity against ROS-overproducing CD44-overexpressing HeLa cells. Additionally, intravenously administered HABN-Cy5.5 showed remarkable tumor-targeting ability in HeLa tumor-bearing mice with limited distribution in major organs. Finally, intravenous injection of DOX@HABN into HeLa tumor-bearing mice showed synergistic anti-tumor efficacy without noticeable side effects. Conclusion: These findings suggest that DOX@HABN has significant potential as a cancer-targeting and TME ROS-responsive nanomedicine for targeted cancer treatment.

Antioxidative Hyaluronic Acid-Bilirubin Nanomedicine Targeting Activated Hepatic Stellate Cells for Anti-Hepatic-Fibrosis Therapy.

Liver fibrosis is a life-threatening and irreversible disease. The fibrosis process is largely driven by hepatic stellate cells (HSCs), which undergo transdifferentiation from an inactivated state to an activated one during persistent liver damage. This activated state is responsible for collagen deposition in liver tissue and is accompanied by increased CD44 expression on the surfaces of HSCs and amplified intracellular oxidative stress, which contributes to the fibrosis process. To address this problem, we have developed a strategy that combines CD44-targeting of activated HSCs with an antioxidative approach. We developed hyaluronic acid-bilirubin nanoparticles (HABNs), composed of endogenous bilirubin, an antioxidant and anti-inflammatory bile acid, and hyaluronic acid, an endogenous CD44-targeting glycosaminoglycan biopolymer. Our findings demonstrate that intravenously administered HABNs effectively targeted the liver, particularly activated HSCs, in fibrotic mice with choline-deficient l-amino acid-defined high-fat diet (CD-HFD)-induced nonalcoholic steatohepatitis (NASH). HABNs were able to inhibit HSC activation and proliferation and collagen production. Furthermore, in a murine CD-HFD-induced NASH fibrosis model, intravenously administered HABNs showed potent fibrotic modulation activity. Our study suggests that HABNs have the potential to serve as a targeted anti-hepatic-fibrosis therapy by modulating activated HSCs via CD44-targeting and antioxidant strategies. This strategy could also be applied to various ROS-related diseases in which CD44-overexpressing cells play a pivotal role.

Glycyrrhizin enhances therapeutic activity of a colon-specific methylprednisolone prodrug against experimental colitis.

BACKGROUND: Co-administration of a reduction inhibitor and a colon-specific prodrug of a glucocorticoid susceptible to colonic reductive metabolism is suggested as a strategy to circumvent the therapeutic loss of the glucocorticoid delivered to and acting locally at the large intestine. AIMS: We examined whether the strategy was feasible as a pharmacotherapy for treatment of inflammatory bowel disease. METHODS: Glycyrrhizin (GCZ), a reduction inhibitor, was tested for its inhibition of the colonic metabolism of methylprednisolone (MP). Therapeutic activity against TNBS-induced rat colitis and adrenal suppression were compared after oral administration of methylprednisolone 21-sulfate sodium (MPS), a colon-specific prodrug of MP, or MPS/GCZ to colitic rats. RESULTS: Upon incubation of MP with the cecal contents, MP disappeared, and this was delayed by addition of GCZ. In addition, more MP produced from MPS in the cecal contents accumulated in the presence of GCZ. Consistent with these results, upon oral administration of MPS/GCZ, MPS or MP, MP was detected at a greater level in the large intestine for MPS/GCZ. MPS/GCZ ameliorated TNBS-induced colitis of rats, and this therapeutic effect was superior to that of MPS and MP. Moreover, MPS/GCZ decreased the plasma levels of corticosterone and ACTH to a greater extent than MPS, but less than MP. CONCLUSIONS: Co-administration of GCZ, a reduction inhibitor, may be a plausible strategy to reduce the therapeutic loss of MP produced from MPS in the large intestine, thus improving the therapeutic property of the prodrug against inflammatory bowel disease.

Optic neuritis associated with seronegative autoimmune encephalitis: a case report.

Optic neuritis is an inflammatory demyelinating disorder that primarily affects the optic nerve and is often associated with multiple sclerosis. While it is rare for optic neuritis to be accompanied by autoimmune encephalitis, it can occur in some cases. A 65-year-old woman with bipolar disorder presented with a progressively altered mentality. Magnetic resonance imaging of the brain showed no definite abnormal findings. Electroencephalography revealed nonconvulsive status epilepticus. Cerebrospinal fluid study and autoimmune and paraneoplastic encephalitis antibodies were negative. The patient was diagnosed with seronegative autoimmune encephalitis and treated with methylprednisolone, intravenous immunoglobulin, and rituximab. Her condition gradually improved except for persistent blindness on the left side. This case highlights the importance of considering autoimmune encephalitis even in the absence of identifiable pathogenic antibodies when clinical manifestations and response to immunotherapy support such a diagnosis.

Hyaluronic acid-bilirubin nanomedicine-based combination chemoimmunotherapy.

Despite significant advances in immune checkpoint blockade (ICB), immunosuppression mediated by tumor-associated myeloid cells (TAMCs) poses a major barrier to cancer immunotherapy. In addition, while immunogenic cell death (ICD) provides a viable approach to inducing anti-tumor immune response, it remains unknown how to effectively trigger ICD while addressing immunosuppressive TAMCs. Here, we show that SC144, a gp130 inhibitor that blocks the IL-6/gp130/STAT3 pathway, induces ICD of tumor cells and polarizes macrophages to M1-phenotype in vitro. However, as SC144 also induces killing of CD8+ T-cells, we sought to deliver SC144 selectively to tumor cells and TAMCs. Toward this goal, we have developed hyaluronic acid-bilirubin nanoparticles (HABN) that accumulate in CD44hi tumor cells and TAMCs. Systemic administration of SC144 loaded in HABN (SC144@HABN) induces apoptosis and ICD of tumor cells, increases the ratio of M1-like to M2-like macrophages, and decreases the frequency of myeloid-derived suppressor cells and CD4+ regulatory T-cells, while promoting anti-tumor CD8+ T-cells. Moreover, SC144@HABN combined with anti-PD-L1 ICB efficiently eliminates MC38 tumors and ICB-resistant 4T1 tumors. Overall, our work demonstrates a therapeutic strategy based on coordinated ICD induction and TAMC modulation and highlights the potential of combination chemoimmunotherapy.

Smart pH-responsive nanomedicines for disease therapy.

Background: Currently nanomedicines are the focus of attention from researchers and clinicians because of the successes of lipid-nanoparticles-based COVID-19 vaccines. Nanoparticles improve existing treatments by providing a number of advantages including protection of cargo molecules from external stresses, delivery of drugs to target tissues, and sustained drug release. To prevent premature release-related side effects, stable drug loading in nanoformulations is required, but the increased stability of the formulation could also lead to a poor drug-release profile at the target sites. Thus, researchers have exploited differences in a range of properties (e.g., enzyme levels, pH, levels of reduced glutathione, and reactive oxygen species) between non-target and target sites for site-specific release of drugs. Among these environmental stimuli, pH gradients have been widely used to design novel, responsive nanoparticles. Area covered: In this review, we assess drug delivery based on pH-responsive nanoparticles at the levels of tissues (tumor microenvironment, pH ~ 6.5) and of intracellular compartments (endosome and lysosome, pH 4.5-6.5). Upon exposure to these pH stimuli, pH-responsive nanoparticles respond with physicochemical changes to their material structure and surface characteristics. These changes include swelling, dissociation, or surface charge switching, in a manner that favors drug release at the target site (the tumor microenvironment region and the cytosol followed by endosomal escape) rather than the surrounding tissues. Expert opinion: Lastly, we consider the challenges involved in the development of pH-responsive nanomedicines.

Effectiveness of yoga training programs to reduce depression and improve resilience of single mothers.

Single mothers are vulnerable to mental health such as depression, but emotional support is insufficient. Yoga is known to be effective in reducing negative emotions and promoting resilience. This study was conducted in order to verify the effectiveness of yoga training programs in reducing depression and improving the resilience of single mothers. Participants in the study included 20 single mothers who belonged to the Single Mothers Association, who were randomly assigned to training (n=10) and nontraining (n=10) groups. The yoga training program for single mothers consisted of Asana yoga, meditation, and mind expression through expert meetings; a total of eight sessions were conducted once a week for 120 min. Testing for depression and resilience was performed before and after the program in order to verify the effectiveness of the program. According to the results of the study, depression in single mothers who participated in the yoga training program was significantly decreased, and resilience was significantly increased. Therefore, the effectiveness of the yoga training program in lowering the depression of single mothers and improving resilience was confirmed. In the future conduct of many studies will be required in order to help the mental health of single mothers.