Increasing Drug Concentration Research Articles

Nose to brain delivery of escitalopram-loaded nano-structured lipid carriers thermosensitive gel: Formulation, physiochemical, pharmacokinetic and pharmacodynamics evaluation

The primary focus of the undertaken research was to design and develop poloxamer-based thermosensitive gel system of escitalopram-loaded nano-structured lipid carriers (ESC-NLCs gel) for nose to brain delivery. ESC-NLCs were optimized using Design Expert® (Version 12). The optimized formulation was encompassed in poloxamer-based thermosensitive gel and was characterized accordingly. In vitro release, ex vivo permeation and in vivo brain and plasma pharmacokinetics was investigated. Additionally, behavioral analysis of the lipopolysaccharide (LPS) induced depressed rats was performed followed by immunohistochemistry of the brain hippocampus and cortex regions. Particle size, polydispersity index and zeta potential of the optimized ESC-NLCs were respectively found as 131 nm, 0.278 and −24.9 mV with excellent entrapment efficiency (96 %). The optimized formulation showed suitable morphology, optimum thermal behavior, amorphous nature and drug-excipient compatibility. ESC-NLCs gel displayed sustained in vitro release profile, whereas permeation was enhanced 27-folds. Brain pharmacokinetics of ESC-NLCs explored 9 folds increased drug concentration in brain. Similarly, improved behavioral changes and reduced neuro inflammatory markers (NF-κB and TNF-α) were observed in LPS induced depressed rats after treatment with ESC-NLCs gel. It can be concluded that ESC-NLCs gel has the potential to sustain the drug release, improve the permeation and bioavailability and reduce the depression after nose to brain delivery in animal model.

Acidic Environment-Responsive Metal Organic Framework-Mediated Dihydroartemisinin Delivery for Triggering Production of Reactive Oxygen Species in Drug-Resistant Lung Cancer.

Dihydroartemisinin (DHA) has emerged as a promising candidate for anticancer therapy. However, the application of DHA in clinics has been hampered by several limitations including poor bioavailability, short circulation life, and low solubility, significantly restricting its therapeutic efficacy and leading to notable side effects during the treatment. We present DHA-loaded zeolitic imidazolate framework-8 (D-ZIF) with controllable and targeted DHA release properties, leading to enhanced antitumor effects while reducing potential side effects. D-ZIF was prepared by one-pot synthesis method using methylimidazole (MIM), Zn(NO3)2•6H2O and DHA. We characterized the physical and chemical properties of D-ZIF by TEM, DLS, XRD, FT-IR, and TG. We measured the drug loading efficiency and the cumulative release of DHA in different pH conditions. We evaluated the cytotoxicity of D-ZIF on renal cell carcinoma (RCC786-O), glioma cells (U251), TAX-resistant human lung adenocarcinoma (A549-TAX) cells by CCK8 in vitro. We explored the possible antitumor mechanism of D-ZIF by Western blot. We evaluated the biocompatibility and hemolysis of D-ZIF and explored the in vivo antitumor efficiency in mice model by TUNEL testing and blood biomarker evaluations. D-ZIF showed rhombic dodecahedral morphology with size of 129±7.2 nm and possessed a noticeable DHA encapsulation efficiency (72.9%). After 48 hours, D-ZIF released a cumulative 70.0% of the loaded DHA at pH 6.5, and only 42.1% at pH 7.4. The pH-triggered programmed release behavior of D-ZIF could enhance anticancer effect of DHA while minimizing side effects under normal physiological conditions. Compared with the free DHA group with 31.75% of A549-TAX cell apoptosis, the percentage of apoptotic cells was approximately 76.67% in the D-ZIF group. D-ZIF inhibited tumor growth by inducing tumor cell apoptosis through the mechanism of ROS production and regulation of Nrf2/HO-1 and P38 MAPK signaling pathways. D-ZIF showed potent effects in treating tumors with high safety in vivo. This pH-responsive release mechanism enhanced the targeting efficiency of DHA towards tumor cells, thereby increasing drug concentration in tumor sites with negligible side effects. Herein, D-ZIF holds great promise for curing cancers with minimal adverse effects.

An in vitro analysis of the interaction between infliximab and granulocyte–monocyte apheresis

ObjectivePrimary non-response and secondary loss of response to anti-TNF agents are common in inflammatory bowel disease. Increasing drug concentrations are correlated to better clinical response and remission rates. Combination of granulocyte–monocyte apheresis (GMA) with anti-tumor necrosis factor (TNF) agents could be an option in these patients. The objective of our study was to perform an in vitro assay to determine if the GMA device can lead to infliximab (IFX) adsorption. Patients and methodsA blood sample was obtained from a healthy control. It was incubated with three concentrations of IFX (3, 6, and 9μg/ml) at room temperature for 10min. At that time, 1ml was collected to determine the IFX concentration. Then, 10ml of each drug concentration was incubated with 5ml of cellulose acetate (CA) beads from the GMA device at 200rpm for 1h at 37°C to simulate physiological human conditions. A second sample of each concentration was collected and IFX levels were determined. ResultsNo statistically significant differences were observed in the IFX levels in the blood samples before and after incubation with the CA beads (p=0.41) and after repeated measurements (p=0.31). Mean change was 3.8μg/ml. ConclusionsThe in vitro combination of GMA and IFX did not change the circulating levels of IFX at the three concentrations tested, suggesting that there is no interaction between the drug and the apheresis device in vitro and that they might be safely combined with each other.

Abstract 2021: The RXR agonist MSU-42011 and the MEK inhibitor selumetinib reduce pERK levels in NF1-deficient cells and inhibit cytokine production in macrophages

Abstract Neurofibromatosis type 1 (NF1) is a common genetic disease that predisposes approximately 50% of affected individuals to develop plexiform neurofibromas (PNFs), which can progress to highly aggressive malignant peripheral nerve sheath tumors (MPNSTs) in approximately 10% of patients. NF1 is caused by mutations in the tumor suppressor gene NF1, which encodes for neurofibromin, a negative regulator of RAS activity. Selumetinib, a specific inhibitor of MEK1/2, is the only FDA-approved drug for NF1-associated PNFs. However, the anti-tumor effects of selumetinib are limited in MPNSTs and have dose-limiting side effects. Deficiency of the NF1 gene not only promotes tumorigenesis but also has broad effects on the immune cells and cytokine signaling driven by hyperactive RAS signaling. Because macrophages account for almost half of cells in NF1 lesions and their infiltration correlates with disease progression, we hypothesized that targeting tumor-promoting immune cells could be an alternative approach for treating NF1. The novel retinoid X receptor (RXR) agonist MSU-42011 reduces tumor growth in experimental Kras-driven cancers by decreasing pERK expression, reducing tumor-promoting immune cells like CD206+ macrophages and regulatory T cells, and increasing activated cytotoxic T cells. Here, we treated NF1-deficient cells and macrophages with MSU-42011 and selumetinib, either alone or in combination, using monoculture and conditioned media (CM) conditions. In human PNF cells and mouse MPNSTs, treatment with 200 nM MSU-40211 or 50 nM selumetinib for 3 hours reduced pERK protein levels compared with untreated controls, and the combination treatment enhanced this reduction in pERK protein levels. Additionally, there was a trend toward reduction in cell viability with increasing drug concentrations after 72 hours of the combination treatment. Moreover, CM from human and mouse PNF cells increased the mRNA expression of monocyte chemoattractant CCL2 (C-C motif chemokine ligand 2) and the secretion of IL-6 and TNFα in human THP1 monocytes/macrophages and bone marrow derived macrophages (BMDM). Notably, MSU-42011 and selumetinib alone inhibited CCL2 mRNA expression in THP1 macrophages and BMDM stimulated with CM from human and mouse PNF cells, respectively, and the inhibition of CCL2 mRNA expression was greatest with combination treatment. The combination of MSU42011 and selumetinib also significantly reduced tumor burden in a LL2 model of lung cancer driven by an activating Kras mutation. Based on the similarities in RAS activation and immune cell infiltration in NF1 and lung cancer, our next step is to confirm the immunomodulatory and anti-tumor effects of MSU-42011 and selumetinib in a syngeneic model of PNF and MPNST. Citation Format: Pei-Yu Hung, Jessica A. Moerland, Karen T. Liby. The RXR agonist MSU-42011 and the MEK inhibitor selumetinib reduce pERK levels in NF1-deficient cells and inhibit cytokine production in macrophages [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 2021.

Biomimetic nanoparticles for effective Celastrol delivery to targeted treatment of rheumatoid arthritis through the ROS-NF-κB inflammasome axis

Previous study has indicated that Celastrol (Cel) has various physiological and pharmacological effects, including antibacterial, antioxidant, pro-apoptotic, anticancer and anti-rheumatoid arthritis (RA) effects. However, low water solubility, low oral bioavailability, narrow treatment window, and high incidence of systemic adverse reactions still limit the further clinical application of Cel. Here, aiming at effectively overcome those shortcomings of Cel to boost its beneficial effects for treating RA, we developed the leukosome (LEUKO) coated biomimetic nanoparticles (NPs) for the targeted delivery of Cel to arthritis injury area in RA. LEUKO were synthesized using membrane proteins purified from activated J774 macrophage. LEUKO and Cel-loaded LEUKO (Cel@LEUKO) were characterized using dynamic light scattering and transmission electron microscopy. Our results demonstrated that Cel@LEUKO can inhibit the inflammatory response of lipopolysaccharide (LPS) induced mouse monocyte macrophage leukemia cells (RAW264.7 cells) and human rheumatoid arthritis synovial fibroblasts (MH7A) cells through the inhibition of reactive oxygen species (ROS)-NF-κB pathway. In addition, research has shown that LEUKO effectively targets and transports Cel to the inflammatory site of RA, increased drug concentration in affected areas, reduced systemic toxicity of Cel, and reduced clinical symptoms, inflammatory infiltration, bone erosion, and serum inflammatory factors in collagen-induced arthritis (CIA) rats.

Synthesis of chitosan-graphene oxide thermosensitive in situ hydrogel for nasal delivery of rasagiline mesylate: In-vitro-ex vivo characterization

Intranasal administration of a drug offers a way to bypass the blood-brain barrier, allowing for an increased drug concentration in the brain and improved bioavailability. In this context, the preference for polymeric thermoresponsive intranasal hydrogels has been widely documented. Here, there is a need to enhance the physical properties of the hydrogel and improve control over the release of the drug. In this work, we propose the incorporation of graphene oxide (GO) into a thermosensitive in situ hydrogel (RM@CS/B-GP-GO) based on chitosan (CS) and beta-glycerophosphate (B-GP) for intranasal delivery of rasagiline mesylate (RM). The prepared in situ hydrogel formulations were characterized using gelation temperature, gelation time, swelling, porosity, gel strength, mucoadhesive strength, pH, morphological features, spectral analysis, drug release, permeation study, and so on. In this work, the incorporation of GO showed a significant concentration-dependent effect on the properties of the thermosensitive CS hydrogel. In brief, the addition of GO in RM@CS/B-GP decreased the gelation time, porosity, and swelling of the hydrogel. Additionally, CS-hydrogel strength increased with higher concentrations of GO. The RM@CS/B-GP-GO hydrogel (1 mg/mL of GO) showed the customized release of RM almost 68.41 ± 2.01 % in 8 h than the RM@CS/B-GP hydrogel (log p < 0.05). Based on these findings, the physical and mechanical properties of the RM@CS/B-GP-GO thermosensitive hydrogel were improved by the addition of optimized concentration GO. Moreover, RM@CS/B-GP-GO hydrogel shows good biocompatibility with nasal mucosa. Overall, the design of RM@CS/B-GP-GO can open new options for the delivery of RM through the nasal route.

The role and the molecular mechanism of abietic acid in the proliferation, invasion and migration of cisplatin-resistant nasopharyngeal carcinoma cells

Objective:To investigate the effects and molecular mechanisms of abietic acid in the cell proliferation, invasion and migration of cisplatin-resistant nasopharyngeal carcinoma cells. Methods:①Cisplatin-resistant C666/DDP cell line was constructed by increasing drug concentration method. ②The effects of abietic acid on proliferation, invasion and migration of C666/DDP cells were investigated by CCK-8 method, reactive oxygen species（ROS） and mitochondrial membrane potential（MMP） level assay and subcutaneous tumorigenesis assay in nude mice to detect the effects of abietic acid on proliferation and apoptosis of C666/DDP cells in vitro and in vivo. The effect of abietic acid on the proliferation and apoptosis of C666/DDP cells in vitro and in vivo was measured by Transwell assay. ③Western blot and IHC method to detect the expression of PI3K/AKT/mTOR pathway related proteins. Results:①The IC50 of cisplatin cytotoxicity to C666-1 was about 25 μmol/L. RI=25 μmol/L /4 μmol/L=6.25, resistance was obtained, and the C666-1-DDP resistant strain was successfully constructed. ②Abietic acid promoted apoptosis and inhibited proliferation of C666/DDP cells, and showed G2/M phase block; transwell showed that abietic acid inhibited C666/DDP cell migration and invasion, increased ROS level of C666/DDP cells and decreased MMP. Transwell showed that abietic acid inhibited the migration and invasion ability of C666/DDP cells, increased the ROS level of C666/DDP cells and decreased MMP. ③Animal experiments showed that abietic acid inhibited the proliferation of cisplatin-resistant nasopharyngeal carcinoma in vivo in a concentration gradient and suppressed the expression of PI3K/AKT/mTOR signaling pathway-related proteins. Conclusion:Abietic acid inhibits proliferation, invasion and migration of cisplatin-resistant nasopharyngeal carcinoma cells by a mechanism related to inhibition of PI3K/AKT/mTOR signaling pathway.

Targeting lipid nanoparticles to the blood-brain barrier to ameliorate acute ischemic stroke

Effective delivery of mRNA or small molecule drugs to the brain is a significant challenge in developing treatment for acute ischemic stroke. To address the problem, we have developed targeted nanomedicine to increase drug concentrations in endothelial cells of the blood-brain barrier (BBB) of the injured brain. Inflammation during ischemic stroke causes continuous neuronal death and increase of the infarct volume. To enable targeted delivery to the inflamed BBB, we conjugated lipid nanocarriers with antibodies that bind cell adhesion molecules expressed at the BBB. In the transient middle cerebral artery occlusion mouse model, nanocarriers targeted to VCAM achieved the highest level of brain delivery, nearly 2 orders of magnitude higher than untargeted ones. VCAM-targeted lipid nanoparticles with luciferase-encoding mRNA and Cre-recombinase showed selective expression in the ischemic brain. Anti-inflammatory drugs administered intravenously after ischemic stroke reduced cerebral infarct volume by 62% (IL-10 mRNA) or 35% (dexamethasone) only when they were encapsulated in VCAM-targeted nanocarriers. Thus, VCAM-targeted lipid nanocarriers represent a new platform for strongly concentrating drugs within the compromised BBB of penumbra, thereby ameliorating acute ischemic stroke.

Therapeutic potential of tocotrienols as chemosensitizers in cancer therapy.

Chemoresistance is the adaptation of cancer cells against therapeutic agents. When exhibited by cancer cells, chemoresistance helps them to avoid apoptosis, cause relapse, and metastasize, making it challenging for chemotherapeutic agents to treat cancer. Various strategies like dosage modification of drugs, nanoparticle-based delivery of chemotherapeutics, antibody-drug conjugates, and so on are being used to target and reverse chemoresistance, one among such is combination therapy. It uses the combination of two or more therapeutic agents to reverse multidrug resistance and improve the effects of chemotherapy. Phytochemicals are known to exhibit chemosensitizing properties and are found to be effective against various cancers. Tocotrienols (T3) and tocopherols (T) are natural bioactive analogs of vitamin E, which exhibit important medicinal value and potential curative properties apart from serving as an antioxidant and nutrient supplement. Notably, T3 exhibits a variety of pharmacological activities like anticancer, anti-inflammatory, antiproliferative, and so on. The chemosensitizing property of tocotrienol is exhibited by modulating several signaling pathways and molecular targets involved in cancer cell survival, proliferation, invasion, migration, and metastasis like NF-κB, STATs, Akt/mTOR, Bax/Bcl-2, Wnt/β-catenin, and many more. T3 sensitizes cancer cells to chemotherapeutic drugs including cisplatin, doxorubicin, and paclitaxel increasing drug concentration and cytotoxicity. Discussed herewith are the chemosensitizing properties of tocotrienols on various cancer cell types when combined with various drugs and biological molecules.

Non-mitotic proliferation of malignant cancer cells revealed through live-cell imaging of primary and cell-line cultures

IntroductionAnti-mitosis has been a key strategy of anti-cancer therapies, targeting at a fundamental property of cancer cells, their non-controllable proliferation due to overactive mitotic divisions. For improved anti-cancer therapies, it is important to find out whether cancer cells can proliferate independent of mitosis and become resistant to anti-mitotic agents.ResultsIn this study, live-cell imaging was applied to both primary-cultures of tumor cells, and immortalized cancer cell lines, to detect aberrant proliferations. Cells isolated from various malignant tumors, such as Grade-III hemangiopericytoma, atypical meningioma, and metastatic brain tumor exhibit distinct cellular behaviors, including amoeboid sequestration, tailing, tunneling, nucleic DNA leakage, as well as prokaryote-like division such as binary fission and budding-shedding, which are collectively referred to and reported as ‘non-mitotic proliferation’ in this study. In contrast, benign tumors including Grade-I hemangiopericytoma and meningioma were not obvious in such behaviors. Moreover, when cultured in medium free of any anti-cancer drugs, cells from a recurrent Grade-III hemangiopericytoma that had been subjected to pre-operation adjuvant chemotherapy gradually shifted from non-mitotic proliferation to abnormal mitosis in the form of daughter number variation (DNV) and endomitosis, and eventually regular mitosis. Similarly, when treated with the anti-cancer drugs Epirubicin or Cisplatin, the cancer cell lines HeLa and A549 showed a shift from regular mitosis to abnormal mitosis, and further to non-mitosis as the dominant mode of proliferation with increasing drug concentrations. Upon removal of the drugs, the cells reversed back to regular mitosis with only minor occurrences of abnormal mitosis, accompanied by increased expression of the stem cell markers ALDH1, Sox, Oct4 and Nanog.ConclusionsThe present study revealed that various types of malignant, but not benign, cancer cells exhibited cellular behaviors indicative of non-mitotic proliferation such as binary fission, which was typical of prokaryotic cell division, suggesting cell level atavism. Moreover, reversible transitions through the three modes of proliferation, i.e., mitosis, abnormal mitosis and non-mitosis, were observed when anticancer drug concentrations were grossly increased inducing non-mitosis or decreased favoring mitosis. Potential clinical significance of non-mitotic proliferation in cancer drug resistance and recurrence, and its relationship with cancer stem cells are worthy of further studies.

Surface activity and micellization of streptomycin sulfate and diphenhydramine hydrochloride in the presence of alkali and alkaline earth metal chlorides

ABSTRACT The study investigated the surface tension of the surface-active drugs streptomycin sulfate and diphenhydramine hydrochloride using three uni-univalent and three bi-univalent electrolytes: NaCl, KCl, and RbCl (0.01 mol.kg−1), and MgCl2, CaCl2, and SrCl2 (0.002 mol.kg−1) over a temperature range of 298.15 to 313.15 K. Surface tension determination has proven instrumental in examining the micellization and surface-active properties of these drugs in the presence of specific electrolytes. The surface tension values of these drugs exhibit a decrease in magnitude with increasing drug concentration, particularly noticeable in streptomycin sulfate. This phenomenon can be elucidated by considering the delicate balance between hydrophobic and hydrophilic forces within the system. Additionally, the impact of the nature of metal halides and temperature on surface tension magnitude has been scrutinised, with interpretations focused on alterations in size. From surface tension values, the interfacial parameters, such as Γ max , A min , and π CMC were examined. The results indicate a strong affinity between drug-electrolyte molecules that reduces the surface tension values. The CMC relations govern the hydrophobic and hydrophilic interactions in the ternary system of water-drug-electrolyte. The thermodynamics of micellization explains the work done for micellization and illuminates the surface and bulk properties of drugs.

Computational drug repurposing for primary hyperparathyroidism

In hyperparathyroidism (hyperPTH), excessive amounts of PTH are secreted, interfering with calcium regulation in the body. Several drugs can control the disease's side effects, but none of them is an alternative treatment to surgery. Therefore, new drug candidates are necessary. In this study, three computationally repositioned drugs, DG 041, IMD 0354, and cucurbitacin I, are evaluated in an in vitro model of hyperPTH. First, we integrated publicly available transcriptomics datasets to propose drug candidates. Using 3D spheroids derived from a single primary hyperPTH patient, we assessed their in vitro efficacy. None of the proposed drugs affected the viability of healthy cell control (HEK293) or overactive parathyroid cells at the level of toxicity. This behavior was attributed to the non-cancerous nature of the parathyroid cells, establishing the hyperPTH disease model. Cucurbitacin I and IMD 0354 exhibited a slight inverse relationship between increased drug concentrations and cell viability, whereas DG 041 increased viability. Based on these results, further studies are needed on the mechanism of action of the repurposed drugs, including determining the effects of these drugs on cellular PTH synthesis and secretion and on the metabolic pathways that regulate PTH secretion.

Major Drug-Drug Interaction Exposure Among Medicaid-Insured Children in the Outpatient Setting.

Drug-drug interactions (DDIs) can cause adverse drug events, but little is known about DDI exposure in children in the outpatient setting. This study aimed to determine the prevalence of major DDI exposure and factors associated with higher DDI exposure rates among children in an outpatient setting. We performed a cross-sectional study of children aged 0 to 18 years with ≥1 ambulatory encounter, and ≥2 dispensed outpatient prescriptions study using the 2019 Marketscan Medicaid database. DDIs (exposure to a major DDI for ≥1 day) and the adverse physiologic effects of each DDI were identified using DrugBank's interaction database. Primary outcomes included the prevalence and rate of major DDI exposure. We used logistic regression to assess patient characteristics associated with DDI exposure. We examined the rate of DDI exposures per 100 children by adverse physiologic effects category, and organ-level effects (eg, heart rate-corrected QT interval prolongation). Of 781 019 children with ≥2 medication exposures, 21.4% experienced ≥1 major DDI exposure. The odds of DDI exposure increased with age and with medical and mental health complexity. Frequently implicated drugs included: Clonidine, psychiatric medications, and asthma medications. The highest adverse physiologic effect exposure rate per 100 children included: Increased drug concentrations (14.6), central nervous system depression (13.6), and heart rate-corrected QT interval prolongation (9.9). One in 5 Medicaid-insured children with ≥2 prescription medications were exposed to major DDIs annually, with higher exposures in those with medical or mental health complexity. DDI exposure places children at risk for negative health outcomes and adverse drug events, especially in the harder-to-monitor outpatient setting.

Non-invasive hERG channel screening based on electrical impedance tomography and extracellular voltage activation (EIT-EVA).

hERG channel screening has been achieved based on electrical impedance tomography and extracellular voltage activation (EIT-EVA) to improve the non-invasive aspect of drug discovery. EIT-EVA screens hERG channels by considering the change in extracellular ion concentration which modifies the extracellular resistance in cell suspension. The rate of ion passing in cell suspension is calculated from the extracellular resistance Rex, which is obtained from the EIT measurement at a frequency of 500 kHz. In the experiment, non-invasive screening is applied by a novel integrated EIT-EVA printed circuit board (PCB) sensor to human embryonic kidney (HEK) 293 cells transfected with the human ether-a-go-go-related gene (hERG) ion channel, while the E-4031 antiarrhythmic drug is used for hERG channel inhibition. The extracellular resistance Rex of the HEK 293 cells suspension is measured by EIT as the hERG channels are activated by EVA over time. The Rex is reconstructed into extracellular conductivity distribution change Δσ to reflect the extracellular K+ ion concentration change Δc resulting from the activated hERG channel. Δc is increased rapidly during the hERG channel non-inhibition state while Δc is increased slower with increasing drug concentration cd. In order to evaluate the EIT-EVA system, the inhibitory ratio index (IR) was calculated based on the rate of Δc over time. Half-maximal inhibitory concentration (IC50) of 2.7 nM is obtained from the cd and IR dose-response relationship. The IR from EIT-EVA is compared with the results from the patch-clamp method, which gives R2 of 0.85. In conclusion, EIT-EVA is successfully applied to non-invasive hERG channel screening.

Triptolide inhibits proliferation and invasion of colorectal cancer cells by blocking Nrf2 expression.

Triptolide (TPL), the main active ingredient of Tripterygium wilfordii, has anti-inflammatory, immunomodulatory, and antitumor actions. It can also inhibit cell proliferation and metastasis while promoting apoptosis of several tumors, such as colorectal cancer (CRC). However, the mechanism of TPL against CRC is not clear. This study was designed to investigate the effects and molecular mechanisms of TPL on the proliferation and invasion ability of CRC cells. A human CRC cell line (HT29 cell line) cultured invitro was treated with different concentrations of TPL (0, 25, 50, and 100 nmol/L). The proliferation of cells was detected by MTT, the invasion ability of cells by Transwell, and the apoptosis level by flow cytometry. The protein expression levels of nuclear factor-erythroid 2-related factor 2 (Nrf2), matrix metalloproteinase (MMP)-2, and MMP-9 were detected by western blotting. After transfection with sh-Nrf2, HT29 cells were divided into NC group, NC + TPL group and sh-Nrf2 + TPL group, and the above assays were repeated for each group. TPL significantly inhibited the proliferation and invasion ability of HT29 cells and promoted apoptosis (p < .05). Notably, its inhibitory or promotional effects were concentration-dependent, which were enhanced with increasing drug concentration (p < .05). After silencing Nrf2 expression, the proliferation, and invasion ability of HT29 cells were further significantly inhibited while cells apoptosis was further promoted (p < .05). Besides, the decreased Nrf2 expression reduced the protein expression levels of MMP-2 and MMP-9 (p < .05). TPL can effectively inhibit the proliferation and invasion while promoting apoptosis of HT29 cells. And its mechanism of action may be related to the inhibition of Nrf2 signaling expression.

What Should We Know about Drug Levels and Therapeutic Drug Monitoring during Pregnancy and Breastfeeding in Inflammatory Bowel Disease under Biologic Therapy?

Data on the real long-term influences of in utero drug exposure in pregnant women on childhood development are scarce and remain not well determined and depend on the duration of in utero drug exposure and maternal drug levels. Therapeutic drug monitoring (TDM) during pregnancy may help limit fetal drug exposure while maintaining an effective dose for the treatment of the underlying inflammatory bowel disease (IBD) in women. Most antibody therapies used in patients with IBD are IgG molecules which are actively transported across the placenta, especially during the third trimester of the pregnancy. Here, we propose an up-to-date clinical review to summarize the available findings of serum drug levels in maternal blood during pregnancy, in the cord blood, infants at delivery and in breast milk of patients with IBD treated with biologics. Conversely, in comparison to adalimumab (ADA) levels, which are relatively stable during pregnancy, infliximab (IFX) drug clearance decreased significantly during the last two trimesters of the pregnancy, leading to increasing drug concentrations in the blood of the pregnant women. As most guidelines recommend using live vaccines in infants at the age of one or earlier in case of negative serum drug levels in newborns, statistical models could help clinicians in making a decision to adjust the last dose of the biologic during pregnancy and to determine the optimal date to vaccinate. Altogether, data from the literature offers strong reassurance in terms of safety for anti-TNFα therapies during pregnancy not only for IBD patients who intend to conceive, but also for pregnant women and for the physicians taking care of these patients. ADA and IFX levels in breast milk are detectable, but at very low levels, and therefore, it is recommended to pursue breast feeding under anti-TNFα therapy. Our knowledge on ustekinumab or vedolizumab levels in pregnant women remains unclear and scarce. These drugs are currently not recommended for patients with IBD in clinical practice. Therefore, TDM and proactive dose adjustment are not necessary during pregnancy since its impact on making a clinical decision have not yet been clearly demonstrated in routine practice. Overall, drug concentrations in the cord blood, an infant at birth and postpartum serum concentrations in infants, due to active placental drug transfer, may have a greater impact than the limited drug transfer in breast milk during lactation on the risk of infection and developmental outcomes. Ustekinumab and vedolizumab exposure during pregnancy and lactation are both considered low risk by the recent ECCO guidelines despite the limited data that are currently available.

A novel strategy to increase the therapeutic potency of GBM chemotherapy via altering parenchymal/cerebral spinal fluid clearance rate

Patients with glioblastoma (GBM) face a poor prognosis with a median survival of less than two years. Escalating the dose of chemotherapy is often impossible due to patient comorbidities; thus, we focused on modulating brain clearance as a mechanism to enhance drug accumulation. Given the recently identified interconnectivity between brain parenchymal fluid and cerebral spinal fluid (CSF), we reasoned enhancing drug concentration in the CSF also increases drug concentration in the parenchyma where a GBM resides. To improve drug accumulation in the CSF, we impair the motility of ependymal cell cilia. We identified FDA-approved therapeutics that interact with cilia as a “side effect.” Therapeutics that inhibit airway cilia also inhibit ependymal cilia. Multiple cilia-inhibiting drugs, when administered in combination with GBM chemotherapy temozolomide (TMZ), significantly improved the overall survival of mice bearing orthotopic GBM. Combining TMZ with lidocaine results in 100% of animals surviving tumor-free to the study endpoint. This treatment results in a ~ 40-fold increase in brain TMZ levels and is well-tolerated. Mice bearing MGMT methylated, human PDX orthotopic GBM also responded with 100% of animals surviving tumor-free to the study endpoint. Finally, even mice bearing TMZ-resistant, orthotopic GBM responded to the combination treatment with 40% of animals surviving tumor-free to the study endpoint, implying this strategy can sensitize TMZ-resistant GBM. These studies offer a new concept for treating malignant brain tumors by improving the accumulation of TMZ in the CNS. In the future, this regimen may also improve the treatment of additional encephalopathies treated by brain-penetrating therapeutics. SignificanceWe exploit the interconnectivity of parenchymal and cerebral spinal fluid to enhance the amount of temozolomide that accumulates in the central nervous system to improve the survival of mice bearing brain tumors.

The effect of PLK1 inhibitor in Osimertinib resistant NCI-H1975 cell lines.

To investigate the effects of PLK1 inhibitors on Osimertinib-resistant NCI-H1975 cell lines and the anti-tumor effect combined with Osimertinib. Osimertinib resistant NCI-H1975 cell lines were constructed by the methods of concentration-increasing.; The classical tumor pathway inhibitor library compounds were combined with Osimertinib on Osimertinib-resistant cells to screen compounds with synergistic effects with Osimertinib; The gene set enrichment analysis (GSEA) was used to investigate the activations of signaling pathways in Osimertinib-resistant cells; Sulforhodamine B (SRB) staining was used to investigate the inhibitory effect of PLK1 inhibitors on Osimertinib-resistant cells and the anti-tumor effect of PLK1 inhibitors combined with Osimertinib. Osimertinib-resistant cells lines H1975-resistance (resistance index=43.45) were successfully established. The PLK1 inhibitors BI 2536 and GSK461324 have synergistic effect with Osimertinib. Compared with Osimertinib-sensitive cells, PLK1 regulatory pathway and cell cycle pathway were significantly activated in Osimertinib-resistant cells. In a cohort of NSCLC patients with epidermal growth factor receptor mutations treated with Osimertinib, PLK1 mRNA levels were negatively correlated with progression free survival of patients (R=0.62, P<0.05), confirming that excessive activation of PLK1 in NSCLC cells may cause cell resistance to Osimertinib. Further vitro experiments showed that, The IC50 of PLK1 inhibitors BI 6727 and GSK461324 in Osimertinib-resistant cells were lower than those in sensitive ones. Compared to the mono treatment of Osimertinib, PLK1 inhibitors combined with Osimertinib behave significantly stronger effect on the proliferation of Osimertinib-resistant cells. PLK1 inhibitors combined with Osimertinib behave stronger anti-tumor effect to Osimertinib-resistant NSCLC cells and may be used for intervention and treatment of Osimertinib resistance.

Pharmacokinetics, quorum-sensing signal molecules and tryptophan-related metabolomics of the novel anti-virulence drug Fluorothiazinon in a Pseudomonas aeruginosa-induced pneumonia murine model

Pseudomonas aeruginosa (PA) infection is commonly associated with hospital-acquired infections in patients with immune deficiency and/or severe lung diseases. Managing this bacterium is complex due to drug resistance and high adaptability. Fluorothiazinon (FT) is an anti-virulence drug developed to suppress the virulence of bacteria as opposed to bacterial death increasing host’s immune response to infection and improving treatment to inhibit drug resistant bacteria. We aimed to evaluate FT pharmacokinetics, quorum sensing signal molecules profiling and tryptophan-related metabolomics in blood, liver, kidneys, and lungs of mice. Study comprised three groups: a group infected with PA that was treated with 400 mg/kg FT (“infected treated group”); a non-infected group, but also treated with the same single drug dose (“non-infected treated group”); and an infected group that received a vehicle (“infected non-treated group”). PA-mediated infection blood pharmacokinetics profiling was indicative of increased drug concentrations as shown by increased Cmax and AUCs. Tissue distribution in liver, kidneys, and lungs, showed that liver presented the most consistently higher concentrations of FT in the infected versus non-infected mice. FT showed that HHQ levels were decreased at 1 h after dosing in lungs while PQS levels were lower across time in lungs of infected treated mice in comparison to infected non-treated mice. Metabolomics profiling performed in lungs and blood of infected treated versus infected non-treated mice revealed drug-associated metabolite alterations, especially in the kynurenic and indole pathways.

A comparison of mutation and amplification-driven resistance mechanisms and their impacts on tumor recurrence.

Tumor recurrence, driven by the evolution of drug resistance is a major barrier to therapeutic success in cancer. Tumor drug resistance is often caused by genetic alterations such as point mutation, which refers to the modification of a single genomic base pair, or gene amplification, which refers to the duplication of a region of DNA that contains a gene. These mechanisms typically confer varying degrees of resistance, and they tend to occur at vastly different frequencies. Here we investigate the dependence of tumor recurrence dynamics on these mechanisms of resistance, using stochastic multi-type branching process models. We derive tumor extinction probabilities and deterministic estimates for the tumor recurrence time, defined as the time when an initially drug sensitive tumor surpasses its original size after developing resistance. For models of amplification-driven and mutation-driven resistance, we prove law of large numbers results regarding the convergence of the stochastic recurrence times to their mean. Additionally, we prove sufficient and necessary conditions for a tumor to escape extinction under the gene amplification model, discuss behavior under biologically relevant parameters, and compare the recurrence time and tumor composition in the mutation and amplification models both analytically and using simulations. In comparing these mechanisms, we find that the ratio between recurrence times driven by amplification versus mutation depends linearly on the number of amplification events required to acquire the same degree of resistance as a mutation event, and we find that the relative frequency of amplification and mutation events plays a key role in determining the mechanism under which recurrence is more rapid for any specific system. In the amplification-driven resistance model, we also observe that increasing drug concentration leads to a stronger initial reduction in tumor burden, but that the eventual recurrent tumor population is less heterogeneous, more aggressive and harbors higher levels of drug-resistance.