Nuclear factor kappa B expression in non-small cell lung cancer.

In this mini-review, we discuss the role of NF-κB, a proinflammatory transcription factor, in the expression of genes involved in inflammation, proliferation, and apoptosis pathways, and link it with prognosis of various human cancers, particularly non-small cell lung cancer (NSCLC). We and others have shown that NF-κB activity can be impacted by post-translational S-glutathionylation through reversible formation of a mixed disulfide bond between its cysteine residues and glutathione (GSH). Clinical data analysis showed that high expression of NF-κB correlated with shorter overall survival (OS) in NSCLC patients, suggesting a tumor promotion function for NF-κB. Moreover, NF-κB expression was associated with tumor stage, lymph node metastasis, and 5-year OS in these patients. NF-κB was over-expressed in the cytoplasm of tumor tissue compared to adjacent normal tissues. S-glutathionylation of NF-κB caused negative regulation by interfering with DNA binding activities of NF-κB subunits. In response to oxidants, S-glutathionylation of NF-κB also correlated with enhanced lung inflammation. Thus, S-glutathionylation is an important contributor to NF-κB regulation and clinical results highlight the importance of NF-κB in NSCLC, where NF-κB levels are associated with unfavorable prognosis.

Alpha-tocopheryl succinate and doxorubicin-loaded liposomes improve drug uptake and tumor accumulation in a murine breast tumor model.

Liposomes composed of a rigid bilayer have high plasma stability; however, they can be challenged in efficacy due to complications in releasing the encapsulated drug as well as being internalized by the tumor cell. On the other hand, fusogenic liposomes may fuse with the plasmatic membrane and release encapsulated material directly into the cytoplasm. In a previous study, fusogenic liposomes composed of alpha-tocopheryl succinate (TS) and doxorubicin (DOX) were developed (pHSL-TS-DOX). These stabilized tumor growth and reduced toxicity compared to a commercial formulation. In the present study, we investigated whether cellular uptake or DOX accumulation in the tumor could justify the better performance of the pHSL-TS-DOX formulation. Release, deformability, and DOX plasmatic concentration studies were also carried out. pHSL-TS-DOX showed an adequate release profile and demonstrated characteristics of a deformable formulation. Data from apoptosis, cell cycle, and nuclear morphology studies have shown that the induction of cell death caused by pHSL-TS-DOX occurred more quickly. Higher DOX cellular uptake and tumor accumulation were observed when pHSL-TS-DOX was administered, demonstrating better drug delivery capacity. Therefore, better DOX uptake as well as tumor accumulation explain the great antitumor activity previously demonstrated for this formulation.

Recent advances in point of care testing for COVID-19 detection.

The World Health Organizations declaration of the COVID-19 pandemic was a milestone for the scientific community. The high transmission rate and the huge number of deaths, along with the lack of knowledge about the virus and the evolution of the disease, stimulated a relentless search for diagnostic tests, treatments, and vaccines. The main challenges were the differential diagnosis of COVID-19 and the development of specific, rapid, and sensitive tests that could reach all people. RT-PCR remains the gold standard for diagnosing COVID-19. However, new methods, such as other molecular techniques and immunoassays emerged. Also, the need for accessible tests with quick results boosted the development of point of care tests (POCT) that are fast, and automated, with high precision and accuracy. This assay reduces the dependence on laboratory conditions and mass testing of the population, dispersing the pressure regarding screening and detection. This review summarizes the advances in the diagnostic field since the pandemic started, emphasizing various laboratory techniques for detecting COVID-19. We reviewed the main existing diagnostic methods, as well as POCT under development, starting with RT-PCR detection, but also exploring other nucleic acid techniques, such as digital PCR, loop-mediated isothermal amplification-based assay (RT-LAMP), clustered regularly interspaced short palindromic repeats (CRISPR), and next-generation sequencing (NGS), and immunoassay tests, and nanoparticle-based biosensors, developed as portable instruments for the rapid standard diagnosis of COVID-19.

pH-sensitive doxorubicin-tocopherol succinate prodrug encapsulated in docosahexaenoic acid-based nanostructured lipid carriers: An effective strategy to improve pharmacokinetics and reduce toxic effects.

Side effects often limit the use of doxorubicin (DOX) in cancer treatment. We have recently developed a nanostructured lipid carrier (NLC) formulation for synergistic chemotherapy, encapsulating DOX and the anticancer adjuvants docosahexaenoic acid (DHA) and α-tocopherol succinate (TS). Hydrophobic ion-pairing with TS allowed a high DOX entrapment in the nanocarrier. In this work, we investigated the pharmacokinetics of this formulation after intravenous administration in mice. The first data obtained led us to propose synthesizing covalent DOX-TS conjugates to increase DOX retention in the NLC. We successfully conjugated DOX to TS via an amide or hydrazone bond. In vitro studies in 4T1 tumor cells indicated low cytotoxicity of the amide derivative, while the hydrazone conjugate was effective in killing cancer cells. We encapsulated the hydrazone derivative in a DHA-based nanocarrier (DOX-hyd-TS/NLC), which had reduced particle size and high drug encapsulation efficiency. The pH-sensitive hydrazone bond allowed controlled DOX release from the NLC, with increased drug release at acidic conditions. In vivo studies revealed that DOX-hyd-TS/NLC had a better pharmacokinetic profile than free DOX and attenuated the short-term cardiotoxic effects caused by DOX, such as QT prolongation and impaired left ventricular systolic function. Moreover, this formulation showed excellent therapeutic performance by reducing tumor growth in 4T1 tumor-bearing mice and decreasing DOX-induced toxicity to the heart and liver, demonstrated by hematologic, biochemical, and histologic analyses. These results indicate that DOX-hyd-TS/NLC may be a promising nanocarrier for breast cancer treatment.

pH-responsive and folate-coated liposomes encapsulating irinotecan as an alternative to improve efficacy of colorectal cancer treatment.

Irinotecan (IRN) is a semisynthetic derivative of camptothecin that acts as a topoisomerase I inhibitor. IRN is used worldwide for the treatment of several types of cancer, including colorectal cancer, however its use can lead to serious adverse effects, as diarrhea and myelosuppression. Liposomes are widely used as drug delivery systems that can improve chemotherapeutic activity and decrease side effects. Liposomes can also be pH-sensitive to release its content preferentially in acidic environments, like tumors, and be surface-functionalized for targeting purposes. Herein, we developed a folate-coated pH-sensitive liposome as a drug delivery system for IRN to reach improved tumor therapy without potential adverse events. Liposomes were prepared containing IRN and characterized for particle size, polydispersity index, zeta potential, concentration, encapsulation, cellular uptake, and release profile. Antitumor activity was investigated in a murine model of colorectal cancer, and its toxicity was evaluated by hematological/biochemical tests and histological analysis of main organs. The results showed vesicles smaller than 200 nm with little dispersion, a surface charge close to neutral, and high encapsulation rate of over 90%. The system demonstrated prolonged and sustained release in pH-dependent manner with high intracellular drug delivery capacity. Importantly, the folate-coated pH-sensitive formulation had significantly better antitumor activity than the pH-dependent system only or the free drug. Tumor tissue of IRN-containing groups presented large areas of necrosis. Furthermore, no evidence of systemic toxicity was found for the groups investigated. Thus, our developed nanodrug IRN delivery system can potentially be an alternative to conventional colorectal cancer treatment.

Thermosensitive Nanosystems Associated with Hyperthermia for Cancer Treatment.

Conventional chemotherapy regimens have limitations due to serious adverse effects. Targeted drug delivery systems to reduce systemic toxicity are a powerful drug development platform. Encapsulation of antitumor drug(s) in thermosensitive nanocarriers is an emerging approach with a promise to improve uptake and increase therapeutic efficacy, as they can be activated by hyperthermia selectively at the tumor site. In this review, we focus on thermosensitive nanosystems associated with hyperthermia for the treatment of cancer, in preclinical and clinical use.

Identification of Staphylococcus aureus infection by aptamers directly radiolabeled with technetium-99m.

INTRODUCTION: Aptamers are oligonucleotides that have high affinity and specificity for their molecular targets which are emerging as a new class of molecules for radiopharmaceuticals development. In this study, aptamers selected to Staphylococcus aureus were evaluated for bacterial infection identification. METHODS: Anti S. aureus aptamers were labeled with (99m)Tc by the direct method. The radiolabel yield and complex stability were assessed by thin-layer chromatography (TLC). Three groups of Swiss mice containing 6 animals each were used. The first group was infected intramuscularly in the right thigh with S. aureus. The second group was infected in the same way with C. albicans and the third group was injected with zymosan to induce aseptic inflammation. After 24 h, radiolabeled aptamers (22.2 MBq) were injected by the tail vein. The mice were euthanized 4 h post injection and tissue sample activities measured in a gamma counter. RESULTS: The (99m)Tc labeled aptamers were stable in saline, plasma and cystein excess. Radiolabeled aptamers showed increased uptake in the kidneys for all groups indicating a main renal excretion, which is consistent with the hydrophilic nature and small size of aptamers. The radiopharmaceutical showed rapid blood clearance indicated by a reduced dose (% ID/g) in the blood. The biodistribution showed that aptamers were able to identify the infection foci caused by S. aureus displaying a target/non-target ratio of 4.0±0.5. This ratio for mice infected with C. albicans was 2.0±0.4 while for mice with aseptic inflammation was 1.2±0.2. Histology confirmed the presence of infection in groups 1 and 2, and inflammation in group 3. CONCLUSIONS: The biodistibution study demonstrated a statistically higher uptake in the S. aureus foci relative to inflammation and C. albicans infected areas. These results highlight the potential of aptamers labeled directly with (99m)Tc for bacterial infection diagnosis by scintigraphy.