Exosomal fragment enclosed polyamine-salt nano-complex for co-delivery of docetaxel and mir-34a exhibits higher cytotoxicity and apoptosis in breast cancer cells.

A novel core-shell nanocarrier system has been designed for co-delivery of a small anticancer drug, docetaxel (DTX) and tumor suppressor (TS) miR-34a named as Exo(PAN34a+DTX). The core is formed by pH dependent polyamine salt aggregates (PSA) containing both the payloads and the shell is formed by RAW 264.7 cell derived exosomal fragments. Herein, phosphate driven polyallylamine hydrochloride (PAH, MW:17,500 Da) PSA was formed in presence of miR-34a and DTX to form PAN34a+DTX. The formulation exhibited pH dependent DTX release with only 33.55 ± 2.12% DTX release at pH 7.2 and 75.21 ± 1.8% DTX release till 144 h at pH 5.5. At 1.21 molar ratio of phosphate to the amine (known as R value), efficient complexation of miR-34a (3.6 µM) in the PAN particles was obtained. PAN34a+DTX demonstrated particle size (163.86 ± 12.89 nm) and zeta-potential value of 17.53 ± 5.10 mV which upon exosomal fragment layering changed to - 7.23 ± 2.75 mV which is similar to the zeta-potential of the exosomal fragments, i.e., - 8.40 ± 1.79 mV. The final formulation Exo(PAN34a+DTX), loaded with 40 ng/mL DTX and 50 nM miR-34a exhibited 48.20 ± 4.59% cytotoxicity in triple negative breast cancer (TNBC) cells, 4T1. Co-localization of CM-DiI (red fluorescence) stained exosomal fragments and FAM-siRNA (green fluorescence) in the cytoplasm of 4T1 cells after 6 h of Exo(PANFAM) treatment confirmed the efficiency of the designed system to co-deliver two actives. Exo(PAN34a+DTX) also reduced BCL-2 expression (target gene for miR-34a) by 8.98 folds in comparison to free DTX confirming promising co-delivery and apoptosis inducing effect of Exo(PAN34a+DTX) in 4T1.

Role of Exosomes in Epithelial-Mesenchymal Transition.

Epithelial-mesenchymal transition (EMT) is a fundamental process driving cancer metastasis, transforming non-motile cells into a motile population that migrates to distant organs and forms secondary tumors. In recent years, cancer research has revealed a strong connection between exosomes and the EMT. Exosomes, a subpopulation of extracellular vesicles, facilitate cellular communication and dynamically regulate various aspects of cancer metastasis, including immune cell suppression, extracellular matrix remodeling, metastasis initiation, EMT initiation, and organ-specific metastasis. Tumor-derived exosomes (TEXs) and their molecular cargo, comprising proteins, lipids, nucleic acids, and carbohydrates, are essential components that promote EMT in cancer. TEXs miRNAs play a crucial role in reprogramming the tumor microenvironment, while TEX surface integrins contribute to organ-specific metastasis. Exosome-based cancer metastasis research offers a deeper understanding about cancer and an effective theranostic platform development. Additionally, various therapeutic sources of exosomes are paving the way for innovative cancer treatment development. In this Review, we spotlight the role of exosomes in EMT and their theranostic impact, aiming to inspire cancer researchers worldwide to explore this fascinating field in more innovative ways.

Choline Transporter regulates olfactory habituation via a neuronal triad of excitatory, inhibitory and mushroom body neurons.

Choline is an essential component of Acetylcholine (ACh) biosynthesis pathway which requires high-affinity Choline transporter (ChT) for its uptake into the presynaptic terminals of cholinergic neurons. Previously, we had reported a predominant expression of ChT in memory processing and storing region of the Drosophila brain called mushroom bodies (MBs). It is unknown how ChT contributes to the functional principles of MB operation. Here, we demonstrate the role of ChT in Habituation, a non-associative form of learning. Odour driven habituation traces are laid down in ChT dependent manner in antennal lobes (AL), projection neurons (PNs), and MBs. We observed that reduced habituation due to knock-down of ChT in MBs causes hypersensitivity towards odour, suggesting that ChT also regulates incoming stimulus suppression. Importantly, we show for the first time that ChT is not unique to cholinergic neurons but is also required in inhibitory GABAergic neurons to drive habituation behaviour. Our results support a model in which ChT regulates both habituation and incoming stimuli through multiple circuit loci via an interplay between excitatory and inhibitory neurons. Strikingly, the lack of ChT in MBs shows characteristics similar to the major reported features of Autism spectrum disorders (ASD), including attenuated habituation, sensory hypersensitivity as well as defective GABAergic signalling. Our data establish the role of ChT in habituation and suggest that its dysfunction may contribute to neuropsychiatric disorders like ASD.

Cervical, Thoracic, and Lumbar Spine Epidural Abscess: Case Report and Literature Review.

We report a case of a spinal epidural abscess (SEA) in a patient without significant risk factors. The patient was treated in an outpatient setting for one week for worsening back pain and subsequently admitted to the hospital for the treatment of sepsis and suspected SEA. An MRI obtained on admission showed an epidural abscess extending from the lower cervical to the upper lumbar region and accompanying paraspinal cervical and psoas abscesses. The patient was successfully treated with antibiotics based on the sensitivity of the surgical cultures received from a needle aspiration of the abscess. SEA has a low incidence; however, the number of cases is consistently rising over the last two decades. The outcome of SEA treatment is related to the duration of the process prior to intuition of the treatment. Patients with no neurological symptoms, or with symptoms lasting less than 36 h, have the best recovery rate. As the typical symptoms of SEA are seen in only 13% of cases, physicians should have a low threshold to order MRI in patients with back pain that is new or changed from the baseline. With the help of CT-guided aspiration for culture analysis, patients can be successfully treated conservatively using antibiotics in cases where neurological signs are absent.

Dissolvable microneedle patch containing doxorubicin and docetaxel is effective in 4T1 xenografted breast cancer mouse model.

Microneedle-devices provide a promising alternative to syringe-injection-based administration of chemotherapeutics. Dissolvable polymeric microneedles provide possibility of carrying greater payload and dual drugs. Here, we report development of polyvinyl pyrrolidone and polyvinyl alcohol composite dissolvable polymeric microneedle system for co-delivery of doxorubicin HCl and docetaxel. Microneedle patches were characterized using stereomicroscope, scanning electron microscope, texture analyzer and confocal microscope. The greatest amount of doxorubicin and docetaxel loaded within one microneedle patch was 533 ±â€¯65 and 227 ±â€¯23 µg, respectively. Ex-vivo studies in excised murine skin revealed insertion of microneedles and permeation of chemotherapeutics without lag time. Microneedles dissolved within 1 h of insertion in excised skin. Effectiveness of the delivery system was determined in 4T1 breast cancer cells xenografted athymic Balb/c mouse model. Intra-tumoral injection of doxorubicin and doxorubicin + docetaxel combination showed significant toxicity to animals evidenced by drastic reduction in the body weight and 100 percent death within 9-days and after 2-dose administration. Interestingly, doxorubicin and docetaxel administered using microneedles either alone or in combination showed significantly greater survival (100% survival after 16-days and 4-dose administration) compared with intratumoral injections. The normalized body weight, tumor volume and DNA fragmentation assay indicated superior effect of microneedle patch application. Furthermore, co-delivery of doxorubicin and docetaxel, controlled the tumor growth better than the administration of single molecules. Taken together, minimally invasive dissolvable microneedle patch application could compliment painful catheter assisted syringe injections to deliver combination chemotherapeutics.