Lapatinib antitumor effect is associated with PI3K and MAPK pathway: An analysis in human and canine prostate cancer cells.

The aberrant activation of HER2 has a pivotal role in bone metastasis implantation and progression in several tumor types, including prostate cancer (PC). Trastuzumab and other anti-HER2 therapies, such as lapatinib, have been used in human breast cancer HER2 positive. Although HER2 overexpression has been reported in PC, anti-HER2 therapy response has revealed conflicting results. We investigated the potential of lapatinib in inhibiting cell migration and inducing apoptosis in two human (LNCaP and PC3) and two canine PC cell lines (PC1 and PC2). Cell migration and apoptosis were evaluated by Annexin V/PI analysis after lapatinib treatment. The transcriptome analysis of all cell lines before and after treatment with lapatinib was also performed. We found increased apoptosis and migration inhibition in LNCaP cells (androgen-sensitive cell line), while PC1, PC2, and PC3 cells showed no alterations after the treatment. The transcriptome analysis of LNCaP and PC3 cell lines showed 158 dysregulated transcripts in common, while PC1 and PC2 cell lines presented 82. At the doses of lapatinib used, we observed transcriptional modifications in all cell lines. PI3K/AKT/mTOR pathway were enriched in human PC cells, while canine PC cells showed enrichment of tyrosine kinase antitumor response and HER2-related pathways. In canine PC cells, the apoptosis failed after lapatinib treatment, possibly due to the downregulation of MAPK genes. Prostate cancer cells insensitive to androgens may be resistant to lapatinib through PI3K gene dysregulation. The association of lapatinib with PI3K inhibitors may provide a more effective antitumor response and clinical benefits to PC patients.

Tucatinib Combination Treatment After Trastuzumab-Deruxtecan in Patients With ERBB2-Positive Metastatic Breast Cancer.

Importance: Little is known regarding the outcomes associated with tucatinib combined with trastuzumab and capecitabine (TTC) after trastuzumab-deruxtecan exposure among patients with ERBB2 (previously HER2)-positive metastatic breast cancer (MBC). Objective: To investigate outcomes following TTC treatment in patients with ERBB2-positive MBC who had previously received trastuzumab-deruxtecan. Design, Setting, and Participants: This cohort study included all patients with MBC who were treated in 12 French comprehensive cancer centers between August 1, 2020, and December 31, 2022. Exposure: Tucatinib combined with trastuzumab and capecitabine administered at the recommended dose. Main Outcomes and Measures: Clinical end points included progression-free survival (PFS), time to next treatment (TTNT), overall survival (OS), and overall response rate (ORR). Results: A total of 101 patients with MBC were included (median age, 56 [range, 31-85] years). The median number of prior treatment lines for metastatic disease at TTC treatment initiation was 4 (range, 2-15), including 82 patients (81.2%) with previous trastuzumab and/or pertuzumab and 94 (93.1%) with previous ado-trastuzumab-emtansine) exposure. The median duration of trastuzumab-deruxtecan treatment was 8.9 (range, 1.4-25.8) months, and 82 patients (81.2%) had disease progression during trastuzumab-deruxtecan treatment, whereas 18 (17.8%) had stopped trastuzumab-deruxtecan for toxic effects and 1 (1.0%) for other reasons. Tucatinib combined with trastuzumab and capecitabine was provided as a third- or fourth-line treatment in 37 patients (36.6%) and was the immediate treatment after trastuzumab-deruxtecan in 86 (85.1%). With a median follow-up of 11.6 (95% CI, 10.5-13.4) months, 76 of 101 patients (75.2%) stopped TTC treatment due to disease progression. The median PFS was 4.7 (95% CI, 3.9-5.6) months; median TTNT, 5.2 (95% CI, 4.5-7.0) months; and median OS, 13.4 (95% CI, 11.1 to not reached [NR]) months. Patients who received TTC immediately after trastuzumab-deruxtecan had a median PFS of 5.0 (95% CI, 4.2-6.0) months; median TTNT of 5.5 (95% CI, 4.8-7.2) months, and median OS of 13.4 (95% CI, 11.9-NR) months. Those who received TTC due to trastuzumab-deruxtecan toxicity-related discontinuation had a median PFS of 7.3 (95% CI, 3.0-NR) months. Best ORR was 29 of 89 patients (32.6%). Sixteen patients with active brain metastasis had a median PFS of 4.7 (95% CI, 3.0-7.3) months, median TTNT of 5.6 (95% CI, 4.4 to NR), and median OS of 12.4 (95% CI, 8.3-NR) months. Conclusions and Relevance: In this study, TTC therapy was associated with clinically meaningful outcomes in patients with ERBB2-positive MBC after previous trastuzumab-deruxtecan treatment, including those with brain metastases. Prospective data on optimal drug sequencing in this rapidly changing therapeutic landscape are needed.

Letermovir prophylaxis for cytomegalovirus in lung-transplant recipients: a comprehensive study with literature review of off-label use and real-world experiences.

Letermovir, initially approved for cytomegalovirus (CMV) prophylaxis in hematopoietic stem-cell transplantation, has gained attention for off-label use in lung-transplant (LTx) recipients. Given the high susceptibility of LTx recipients to CMV infection, this study explores the effectiveness and safety of letermovir prophylaxis. A retrospective analysis of using letermovir for LTx recipients at Tohoku University Hospital (January 2000 to November 2023) was conducted. Case summaries from other Japanese transplant centers and a literature review were included. Six cases at Tohoku University Hospital and one at Kyoto University Hospital were identified. Prophylactic letermovir use showed positive outcomes in managing myelosuppression and preventing CMV replication. The literature review supported the safety of letermovir in high-risk LTx recipients. Despite limited reports, our findings suggest letermovir's potential as prophylaxis for LTx recipients intolerant to valganciclovir. Safety, especially in managing myelosuppression, positions letermovir as a promising option. However, careful consideration is important in judiciously integrating letermovir into the treatment protocol.

Telangiectasias induced by combination tucatinib and ado-trastuzumab emtansine in a patient with metastatic breast cancer.

BACKGROUND: Tucatinib is a tyrosine kinase inhibitor currently used in salvage therapy for human epidermal growth factor receptor 2 (HER2)-positive breast and colorectal cancer. The use of tucatinib alone or in combination with ado-trastuzumab emtansine (T-DM1) in the treatment of advanced HER2-positive cancers is rapidly expanding. OBJECTIVE/METHODS: We report the case of a 66-year-old female who presented to the dermatology clinic with a one-year history of widespread telangiectasias that began after initiation of combination chemotherapy with tucatinib and T-DM1 for metastatic HER2-positive invasive ductal carcinoma. RESULTS: The patient's lesions regressed upon cessation of combination therapy and reappeared in the setting of tucatinib re-initiation, with gradual improvement over the following four months following electrocautery to the affected regions. CONCLUSIONS: We postulate that telangiectasias may be a previously unreported dermatologic side effect of combination treatment with tucatinib and T-DM1. Electrocautery is a safe and effective procedure to reduce the appearance of telangiectasias and improve patient satisfaction during chemotherapy.

Synergistic anti-tumor effects of lenalidomide and gefitinib by upregulating ADRB2 and inactivating the mTOR/PI3K/AKT signaling pathway in lung adenocarcinoma.

Gefitinib is commonly used to be the first-line therapy for advanced non-small cell lung cancer (NSCLC). Therapeutic effect of gefitinib is reduced due to acquired resistance, and combined treatment is recommended. In this research, we planned to explore the impacts of combined treatment of lenalidomide and gefitinib on gefitinib-sensitive or -resistant NSCLC cells. The co-treatment results demonstrated that enhanced antitumor impact on NSCLC cell growth, migration, invasion, cell cycle process and apoptosis. The tumor-bearing mouse models were established using PC9/GR cells. In vivo assays also showed that lenalidomide and gefitinib synergistically inhibited mouse tumor growth along increased the survival of mice. ADRB2 was identified as a lowly expressed gene in PC9/GR cells and LUAD tumor tissues. LUAD patients with high ADRB2 expression were indicated with favorable survival outcomes. Moreover, ADRB2 was upregulated in lenalidomide and/or gefitinib-treated PC9/GR cells. ADRB2 deficiency partially offsets the suppressive impacts of lenalidomide and gefitinib co-treatment on the viability and proliferation of PC9/GR cells. Additionally, lenalidomide and gefitinib cotreatment significantly inactivated the mTOR/PI3K/AKT signaling pathway compared with each treatment alone. Rescue assays were performed to explore whether lenalidomide and gefitinib synergistically inhibited the growth of PC9/GR cells via the PI3K/AKT pathway. PI3K activator SC79 significantly restored reduced cell proliferation, migration and invasion along with elevated cell cycle arrest and apoptosis caused by lenalidomide and gefitinib cotreatment. In conclusion, lenalidomide and gefitinib synergistically suppressed LUAD progression and attenuated gefitinib resistance by upregulating ADRB2 and inactivating the mTOR/PI3K/AKT signaling pathway in lung adenocarcinoma.

Efficacy of tyrosine kinase inhibitors examined by a combination of Raman micro-spectroscopy and a deep wavelet scattering-based multivariate analysis framework.

HER2 is a crucial therapeutic target in breast cancer, and the survival rate of breast cancer patients has increased because of this receptor's inhibition. However, tumors have shown resistance to this therapeutic strategy due to oncogenic mutations that decrease the binding of several HER2-targeted drugs, including lapatinib, and confer resistance to this drug. Neratinib can overcome this drug resistance and effectively inhibit HER2 signaling and tumor growth. In the present study, we examined the efficacy of lapatinib and neratinib using breast cancer cells by Raman microscopy combined with a deep wavelet scattering-based multivariate analysis framework. This approach discriminated between control cells and drug-treated cells with high accuracy, compared to classical principal component analysis. Both lapatinib and neratinib induced changes in the cellular biochemical composition. Furthermore, the Raman results were compared with the results of several in vitro assays. For instance, drug-treated cells exhibited (i) inhibition of ERK and AKT phosphorylation, (ii) inhibition of cellular proliferation, (iii) cell-cycle arrest, and (iv) apoptosis as indicated by western blotting, real-time cell analysis (RTCA), cell-cycle analysis, and apoptosis assays. Thus, the observed Raman spectral changes are attributed to cell-cycle arrest and apoptosis. The results also indicated that neratinib is more potent than lapatinib. Moreover, the uptake and distribution of lapatinib in cells were visualized through its label-free marker bands in the fingerprint region using Raman spectral imaging. These results show the prospects of Raman microscopy in drug evaluation and presumably in drug discovery.

Discovery of anticancer function of Febrifugine: Inhibition of cell proliferation, induction of apoptosis and suppression steroid synthesis in bladder cancer cells.

Bladder cancer is a prevalent malignancy affecting the urinary system, which presents a significant global health concern. Although there are many treatments for bladder cancer, identifying more effective drugs and methods remains an urgent problem. As a pivotal component of contemporary medical practice, traditional Chinese medicine (TCM) assumes a crucial role in the realm of anti-tumor therapy, especially with the identification of active ingredients and successful exploration of pharmacological effects. Febrifugine, identified as a quinazoline-type alkaloid compound extracted from the Cytidiaceae family plant Huangchangshan, exhibits heightened sensitivity to bladder cancer cells in comparison to control cells (non-cancer cells) group. The proliferation growth of bladder cancer cells T24 and SW780 was effectively inhibited by Febrifugine, and the IC50 was 0.02 and 0.018 µM respectively. Febrifugine inhibits cell proliferation by suppressing DNA synthesis and induces cell death by reducing steroidogenesis and promoting apoptosis. Combined with transcriptome analysis, Febrifugine was found to downregulate low density lipoprotein receptor-associated protein, lanosterol synthase, cholesterol biosynthesis second rate-limiting enzyme, 7-dehydrocholesterol reductase, flavin adenine dinucleotide dependent oxidoreductase and other factors to inhibit the production of intracellular steroids in bladder cancer T24 cells. The results of animal experiments showed that Febrifugine could inhibit tumor growth. In summary, the effect of Febrifugine on bladder cancer is mainly through reducing steroid production and apoptosis. Therefore, this study contributes to the elucidation of Febrifugine's potential as an inhibitor of bladder cancer and establishes a solid foundation for the future development of novel therapeutic agents targeting bladder cancer.

Tryptanthrin Derivative B1 Binds Viral Genome-Linked Protein (VPg) of Potato Virus Y.

Potato virus Y (PVY) is a plant virus that is known to be responsible for substantial economic losses in agriculture. Within the PVY genome, viral genome-linked protein (VPg) plays a pivotal role in the viral translation process. In this study, VPg was used as a potential target for analyzing the antiviral activity of tryptanthrin derivatives. In vitro, the dissociation constants of B1 with PVY VPg were 0.69 µmol/L (measured by microscale thermophoresis) and 4.01 µmol/L (measured via isothermal titration calorimetry). B1 also strongly bound to VPg proteins from three other Potyviruses. Moreover, in vivo experiments demonstrated that B1 effectively suppressed the expression of the PVY gene. Molecular docking experiments revealed that B1 formed a hydrogen bond with N121 and that no specific binding occurred between B1 and the PVY VPgN121A mutant. Therefore, N121 is a key amino acid residue in PVY VPg involved in B1 binding. These results highlight the potential of PVY VPg as a potential target for the development of antiviral agents.

Letermovir use may impact on the Cytomegalovirus DNA fragmentation profile in plasma from allogeneic hematopoietic stem cell transplant recipients.

Cytomegalovirus (CMV) DNA in plasma is mainly unprotected and highly fragmented. The size of the amplicon largely explains the variation in CMV DNA loads quantified across PCR platforms. In this proof-of-concept study, we assessed whether the CMV DNA fragmentation profile may vary across allogeneic hematopoietic stem cell transplant recipients (allo-SCT), within the same patient over time, or is affected by letermovir (LMV) use. A total of 52 plasma specimens from 14 nonconsecutive allo-SCT recipients were included. The RealTime CMV PCR (Abbott Molecular), was used to monitor CMV DNA load in plasma, and fragmentation was assessed with a laboratory-designed PCR generating overlapping amplicons (around 90-110 bp) within the CMV UL34, UL80.5, and UL54 genes. Intrapatient, inter-patient, and LMV-associated qualitative and quantitative variations in seven amplicons were observed. These variations were seemingly unrelated to the CMV DNA loads measured by the Abbott PCR assay. CMV DNA loads quantified by UL34_4, UL54.5, and UL80.5_1 PCR assays discriminate between LMV and non-LMV patients. Our observations may have relevant implications in the management of active CMV infection in allo-SCT recipients, either treated or not with LMV, although the data need further validation.

Synthesis of bioactive evodiamine and rutaecarpine analogues under ball milling conditions.

Mechanochemical reactions achieved by processes such as milling and grinding are promising alternatives to traditional solution-based chemistry. This approach not only eliminates the need for large amounts of solvents, thereby reducing waste generation, but also finds applications in chemical and materials synthesis. The focus of this study is on the synthesis of quinazolinone derivatives by ball milling, in particular evodiamine and rutaecarpine analogues. These compounds are of interest due to their diverse bioactivities, including potential anticancer properties. The study examines the reactions carried out under ball milling conditions, emphasizing their efficiency in terms of shorter reaction times and reduced environmental impact compared to conventional methods. The ball milling reaction of evodiamine and rutaecarpine analogues resulted in yields of 63-78% and 22-61%, respectively. In addition, these compounds were tested for their cytotoxic activity, and evodiamine exhibited an IC50 of 0.75 ± 0.04 µg mL-1 against the Ca9-22 cell line. At its core, this research represents a new means to synthesise these compounds, providing a more environmentally friendly and sustainable alternative to traditional approaches.

YES1 as a potential target to overcome drug resistance in EGFR-deregulated non-small cell lung cancer.

Epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors (TKIs) such as gefitinib and osimertinib have primarily been used as first-line treatments for patients with EGFR-activating mutations in non-small cell lung cancer (NSCLC). Novel biomarkers are required to distinguish patients with lung cancer who are resistant to EGFR-TKIs. The aim of the study is to investigate the expression and functional role of YES1, one of the Src-family kinases, in EGFR-TKI-resistant NSCLC. YES1 expression was elevated in gefitinib-resistant HCC827 (HCC827/GR) cells, harboring EGFR mutations. Moreover, HCC827/GR cells exhibited increased reactive oxygen species (ROS) levels compared to those of the parent cells, resulting in the phosphorylation/activation of YES1 due to oxidation of the cysteine residue. HCC827/GR cells showed elevated expression levels of YES1-associated protein 1 (YAP1), NF-E2-related factor 2 (Nrf2), cancer stemness-related markers, and antioxidant proteins compared to those of the parent cells. Knockdown of YES1 in HCC827/GR cells suppressed YAP1 phosphorylation, leading to the inhibition of Bcl-2, Bcl-xL, and Cyclin D1 expression. Silencing YES1 markedly attenuated the proliferation, migration, and tumorigenicity of HCC827/GR cells. Dasatinib inhibited the proliferation of HCC827/GR cells by targeting YES1-mediated signaling pathways. Furthermore, the combination of gefitinib and dasatinib demonstrated a synergistic effect in suppressing the proliferation of HCC827/GR cells. Notably, YES1- and Nrf2-regulated genes showed a positive regulatory relationship in patients with lung cancer and in TKI-resistant NSCLC cell lines. Taken together, these findings suggest that modulation of YES1 expression and activity may be an attractive therapeutic strategy for the treatment of drug-resistant NSCLC.

Erlotinib combination with a mitochondria-targeted ubiquinone effectively suppresses pancreatic cancer cell survival.

BACKGROUND: Pancreatic cancer is a leading cause of cancer-related deaths. Increased activity of the epidermal growth factor receptor (EGFR) is often observed in pancreatic cancer, and the small molecule EGFR inhibitor erlotinib has been approved for pancreatic cancer therapy by the food and drug administration. Nevertheless, erlotinib alone is ineffective and should be combined with other drugs to improve therapeutic outcomes. We previously showed that certain receptor tyrosine kinase inhibitors can increase mitochondrial membrane potential (Δψm), facilitate tumor cell uptake of Δψm-sensitive agents, disrupt mitochondrial homeostasis, and subsequently trigger tumor cell death. Erlotinib has not been tested for this effect. AIM: To determine whether erlotinib can elevate Δψm and increase tumor cell uptake of Δψm-sensitive agents, subsequently triggering tumor cell death. METHODS: Δψm-sensitive fluorescent dye was used to determine how erlotinib affects Δψm in pancreatic adenocarcinoma (PDAC) cell lines. The viability of conventional and patient-derived primary PDAC cell lines in 2D- and 3D cultures was measured after treating cells sequentially with erlotinib and mitochondria-targeted ubiquinone (MitoQ), a Δψm-sensitive MitoQ. The synergy between erlotinib and MitoQ was then analyzed using SynergyFinder 2.0. The preclinical efficacy of the two-drug combination was determined using immune-compromised nude mice bearing PDAC cell line xenografts. RESULTS: Erlotinib elevated Δψm in PDAC cells, facilitating tumor cell uptake and mitochondrial enrichment of Δψm-sensitive agents. MitoQ triggered caspase-dependent apoptosis in PDAC cells in culture if used at high doses, while erlotinib pretreatment potentiated low doses of MitoQ. SynergyFinder suggested that these drugs synergistically induced tumor cell lethality. Consistent with in vitro data, erlotinib and MitoQ combination suppressed human PDAC cell line xenografts in mice more effectively than single treatments of each agent. CONCLUSION: Our findings suggest that a combination of erlotinib and MitoQ has the potential to suppress pancreatic tumor cell viability effectively.

ERBB1 alleviates secondary brain injury induced by experimental intracerebral hemorrhage in rats by modulating neuronal death via PLC-γ/PKC pathway.

AIMS: Intracerebral hemorrhage (ICH) is a disease with high rates of disability and mortality. The role of epidermal growth factor receptor 1 (ERBB1) in ICH was elucidated in this study. METHODS: ICH model was constructed by injecting autologous arterial blood into the right basal ganglia. The protein level of ERBB1 was detected by western blot analysis. To up- and downregulation of ERBB1 in rats, intraventricular injection of a lentivirus overexpression vector of ERBB1 and AG1478 (a specific inhibitor of ERBB1) was used. The cell apoptosis, neuronal loss, and pro-inflammatory cytokines were assessed by TUNEL, Nissl staining, and ELISA. Meanwhile, behavioral cognitive impairment of ICH rats was evaluated after ERBB1-targeted interventions. RESULTS: ERBB1 increased significantly in brain tissue of ICH rats. Overexpression of ERBB1 remarkably reduced cell apoptosis and neuronal loss induced by ICH, as well as pro-inflammatory cytokines and oxidative stress. Meanwhile, the behavioral and cognitive impairment of ICH rats were alleviated after upregulation of ERBB1; however, the secondary brain injury (SBI) was aggravated by AG1478 treatment. Furthermore, the upregulation of PLC-γ and PKC in ICH rats was reversed by AG1478 treatment. CONCLUSIONS: ERBB1 can improve SBI and has a neuroprotective effect in experimental ICH rats via PLC-γ/PKC pathway.

Hit-to-lead optimization of 2-aminoquinazolines as anti-microbial agents against Leishmania donovani.

Visceral leishmaniasis is a potentially fatal disease caused by infection by the intracellular protist pathogens Leishmania donovani or Leishmania infantum. Present therapies are ineffective because of high costs, variable efficacy against different species, the requirement for hospitalization, toxicity and drug resistance. Detailed analysis of previously published hit molecules suggested a crucial role of 'guanidine' linkage for their efficacy against L. donovani. Here we report the design of 2-aminoquinazoline heterocycle as a basic pharmacophore-bearing guanidine linkage. The introduction of various groups and functionality at different positions of the quinazoline scaffold results in enhanced antiparasitic potency with modest host cell cytotoxicity using a physiologically relevant THP-1 transformed macrophage infection model. In terms of the ADME profile, the C7 position of quinazoline was identified as a guiding tool for designing better molecules. The good ADME profile of the compounds suggests that they merit further consideration as lead compounds for treating visceral leishmaniasis.

Design, synthesis and biological evaluation of quinazoline and pyrrolo[3,2-d]pyrimidine derivatives as TLR7 agonists for antiviral agents.

Pattern recognition receptors (PRRs) play a critical role in the innate immune response, and toll-like receptor 7 (TLR7) is an important member of PRRs. Although several TLR7 agonists are available, most of them are being tested clinically, with only one available on the market. Thus, it is imperative to develop new TLR7 agonists. In this study, we designed and synthesized three kinds of quinazoline derivatives and five kinds of pyrrolo[3,2-d]pyrimidine derivatives targeting TLR7. The antiviral efficacy of these compounds was evaluated in vitro and in vivo. Our findings indicated that four kinds of compounds showed exceptional antiviral activity. Furthermore, molecular docking studies confirmed that compound 11 successfully positioned itself in the pocket of the TLR7 guanosine loading site with a binding energy of -4.45 kcal mol-1. These results suggested that these compounds might be potential antiviral agents.

A pyrene-induced PET-based chemosensor for biologically important Zn(II) ions: application in test strips and live cell imaging studies.

Cation and anion sensing is vital owing to their universal dispersion in ecosystems and biological functions. It has been shown that fluorescent receptors based on organic platforms are efficient for detecting a number of ions and have many advantages such as low cost, superior sensitivity and simplicity in installation. This study demonstrates the design and synthesis of a novel receptor (E)-3-[(3,5-di-tert-butyl-2-hydroxybenzylidene)amino]-2-(pyren-1-yl)-2,3-dihydroquinazolin-4(1H)-one (DTQ) for the rapid recognition of Zn(II) ions. DTQ exhibited a significant fluorometric "turn-on" characteristic towards Zn(II) at λmax 444 nm in aqueous acetonitrile by inhibiting the photo-induced electron transfer (PET) and -CN- process. The ESI-MS analysis and Job's plot experimental results confirmed stoichiometric 1 : 1 complex formation between DTQ and Zn(II). Fluorometric investigations revealed the detection limit and association constant of DTQ towards Zn(II), which were found to be 13.4 nM and 1.47 × 105 M-1, respectively. DTQ was employed to sense Zn(II) on low-cost test strips. The present research findings imply that DTQ can function as an effective sensor for Zn(II).

Redirecting raltitrexed from cancer cell thymidylate synthase to Mycobacterium tuberculosis phosphopantetheinyl transferase.

There is a compelling need to find drugs active against Mycobacterium tuberculosis (Mtb). 4'-Phosphopantetheinyl transferase (PptT) is an essential enzyme in Mtb that has attracted interest as a potential drug target. We optimized a PptT assay, used it to screen 422,740 compounds, and identified raltitrexed, an antineoplastic antimetabolite, as the most potent PptT inhibitor yet reported. While trying unsuccessfully to improve raltitrexed's ability to kill Mtb and remove its ability to kill human cells, we learned three lessons that may help others developing antibiotics. First, binding of raltitrexed substantially changed the configuration of the PptT active site, complicating molecular modeling of analogs based on the unliganded crystal structure or the structure of cocrystals with inhibitors of another class. Second, minor changes in the raltitrexed molecule changed its target in Mtb from PptT to dihydrofolate reductase (DHFR). Third, the structure-activity relationship for over 800 raltitrexed analogs only became interpretable when we quantified and characterized the compounds' intrabacterial accumulation and transformation.

Effect of vine leaves processing on Azoxystrobin, Fenazaquin and Indoxacarb residues dissipation: processing factors and consumer safety assessment.

The effect of vine leaves processing techniques on Azoxystrobin, Fenazaquin, and Indoxacarb residues was investigated. Residue extraction following field application of pesticides and leaf processing was carried out using the QuEChERS method, with analysis conducted by LC-MS/MS. In dry conservation, Azoxystrobin's half-life was estimated to exceed a year, Fenazaquin's was 18 days, and Indoxacarb's was 142 days. Azoxystrobin had a half-life of 261 days, Fenazaquin had a half-life of 9 days, and Indoxacarb's half-life exceeded a year in brine conservation. It is recommended to use dry conservation because it results in an average 60 % reduction in residue levels for the three pesticides. Boiling water significantly reduced pesticide residues (Azoxystrobin -40.3 %, Indoxacarb -22.4 %, and Fenazaquin -28.8 %). It is recommended to use boiling water for washing, as it shows an average removal rate of approximately 30 %. The health risk assessment indicated that consuming vine leaves posed no health risk for consumers, but overall exposure to residues must be considered.

Activation of epidermal growth factor receptors in triple-negative breast cancer cells by morphine; analysis through Raman spectroscopy and machine learning.

Triple negative breast cancer (TNBC) is a very aggressive form of breast cancer, and the analgesic drug morphine has been shown to promote the proliferation of TNBC cells. This article investigates whether morphine causes activation of epidermal growth factor receptors (EGFR), the roles of µ-opioid and EGFR receptors on TNBC cell proliferation and migration. While examining the changes with molecular techniques, we also aimed to investigate the analysis ability of Raman spectroscopy and machine learning-based approach. Effects of morphine on the proliferation and migration of MDA.MB.231 cells were evaluated by MTT and scratch wound-healing tests, respectively. Morphine-induced phosphorylation of the EGFR was analyzed by western blotting in the presence and absence of µ-receptor antagonist naltrexone and the EGFR-tyrosine kinase inhibitor gefitinib. Morphine-induced EGFR phosphorylation and cell migration were significantly inhibited by pretreatments with both naltrexone and gefitinib; however, morphine-increased cell proliferation was inhibited only by naltrexone. While morphine-induced changes were observed in the Raman scatterings of the cells, the inhibitory effect of naltrexone was analyzed with similarity to the control group. Principal component analysis (PCA) of the Raman confirmed the epidermal growth factor (EGF)-like effect of morphine and was inhibited by naltrexone and partly by gefitinib pretreatments. Our in vitro results suggest that combining morphine with an EGFR inhibitor or a peripherally acting opioidergic receptor antagonist may be a good strategy for pain relief without triggering cancer proliferation and migration in TNBC patients. In addition, our results demonstrated the feasibility of the Raman spectroscopy and machine learning-based approach as an effective method to investigate the effects of agents in cancer cells without the need for complex and time-consuming sample preparation. The support vector machine (SVM) with linear kernel automatically classified the effects of drugs on cancer cells with ∼95% accuracy.

Humanization of SLCO2B1 in Rats Increases rCYP3A1 Protein Expression but Not the Metabolism of Erlotinib to OSI-420.

The organic anion transporting polypeptide (OATP)2B1 [(gene: solute carrier organic anion transporter family member 2B1 (SLCO2B1)] is an uptake transporter that facilitates cellular accumulation of its substrates. Comparison of SLCO2B1+/+ knockin and rSlco2b1-/- knockout rats showed a higher expression of rCYP3A1 in the humanized animals. We hypothesize that humanization of OATP2B1 not only affects cellular uptake but also metabolic activity. To further investigate this hypothesis, we used SLCO2B1+/+ and rSlco2b1-/ - rats and the OATP2B1 and rCYP3A1 substrate erlotinib, which is metabolized to OSI-420, for in vivo and ex vivo experiments. One hour after administration of a single dose of erlotinib, the knockin rats exhibited significantly lower erlotinib serum levels, but no change was observed in metabolite concentration or the OSI-420/erlotinib ratio. Similar results were obtained for liver tissue levels comparing SLCO2B1+/+ and rSlco2b1-/- rats. Liver microsomes isolated from the erlotinib-treated animals were characterized ex vivo for rCYP3A activity using testosterone, showing higher activity in the knockin rats. The contrary was observed when microsomes isolated from treatment-naïve animals were assessed for the metabolism of erlotinib to OSI-420. The latter is in contrast to the higher rCYP3A1 protein amount observed by western blot analysis in rat liver lysates and liver microsomes isolated from untreated rats. In summary, rats humanized for OATP2B1 showed higher expression of rCYP3A1 in liver and reduced serum levels of erlotinib but no change in the OSI-420/erlotinib ratio despite a lower OSI-420 formation in isolated liver microsomes. Studies with CYP3A-specific substrates are warranted to evaluate whether humanization affects not only rCYP3A1 expression but also metabolic activity in vivo. SIGNIFICANCE STATEMENT: Humanization of rats for the organic anion transporting polypeptide (OATP)2B1 increases rCYP3A1 expression and activity in liver. Using the OATP2B1/CYP3A-substrate erlotinib to assess the resulting phenotype, we observed lower erlotinib serum and liver concentrations but no impact on the liver/serum ratio. Moreover, there was no difference in the OSI-420/erlotinib ratio comparing humanized and knockout rats, suggesting that OSI-420 is not applicable to monitor differences in rCYP3A1 expression as supported by data from ex vivo experiments with rat liver microsomes.