LTK mutations responsible for resistance to lorlatinib in non-small cell lung cancer harboring CLIP1-LTK fusion.

The CLIP1-LTK fusion was recently discovered as a novel oncogenic driver in non-small cell lung cancer (NSCLC). Lorlatinib, a third-generation ALK inhibitor, exhibited a dramatic clinical response in a NSCLC patient harboring CLIP1-LTK fusion. However, it is expected that acquired resistance will inevitably develop, particularly by LTK mutations, as observed in NSCLC induced by oncogenic tyrosine kinases treated with corresponding tyrosine kinase inhibitors (TKIs). In this study, we evaluate eight LTK mutations corresponding to ALK mutations that lead to on-target resistance to lorlatinib. All LTK mutations show resistance to lorlatinib with the L650F mutation being the highest. In vitro and in vivo analyses demonstrate that gilteritinib can overcome the L650F-mediated resistance to lorlatinib. In silico analysis suggests that introduction of the L650F mutation may attenuate lorlatinib-LTK binding. Our study provides preclinical evaluations of potential on-target resistance mutations to lorlatinib, and a novel strategy to overcome the resistance.

Cost-effectiveness of first-line versus second-line use of brigatinib followed by lorlatinib in patients with ALK-positive non-small cell lung cancer.

Background: The ALTA-1 L trial and EXP-3B arm of NCT01970865 trial found that both brigatinib and lorlatinib showed durable and robust responses in treating ALK-positive non-small cell lung cancer (NSCLC) patients. However, brigatinib and lorlatinib treatments are costly and need indefinite administration until the disease progression. Thus, it remains uncertain whether using brigatinib followed by lorlatinib before chemotherapy is cost-effective compared to reserving these two drugs until progression after chemotherapy. Methods: We used a Markov model to assess clinical outcomes and healthcare costs of treating ALK-positive NSCLC individuals with brigatinib followed by lorlatinib before chemotherapy versus a strategy of reserving these drugs until progression after chemotherapy. Transition probabilities were estimated using parametric survival modeling based on multiple clinical trials. The drug acquisition costs, adverse events costs, administration costs were extracted from published studies before and publicly available data. We calculated lifetime direct healthcare costs, quality-adjusted life-years (QALYs), and incremental cost-effectiveness ratios from the perspective of a United States payer. Results: Our base-case analysis indicated that the incremental cost-effectiveness ratios of using first-line brigatinib followed by lorlatinib compared with second-line brigatinib followed by lorlatinib is $-400,722.09/QALY which meant that second-line brigatinib followed by lorlatinib had less costs and better outcomes. Univariate sensitivity analysis indicated the results were most sensitive to the cost of brigatinib. Probability sensitivity analysis revealed that using brigatinib followed by lorlatinib before chemotherapy had a 0% probability of cost-effectiveness versus delaying these two drugs until progression after chemotherapy at a willingness-to-pay threshold of $150,000 per QALY. Sensitivity analyses conducted revealed the robustness of this result, as incremental cost-effectiveness ratios never exceeded the willingness-to-pay threshold. Conclusion: Using brigatinib as first-line treatment followed by lorlatinib for ALK-positive NSCLC may not be cost-effective given current pricing from the perspective of a United States payer. Delaying brigatinib followed by lorlatinib until subsequent lines of treatment may be a reasonable strategy that could limit healthcare costs without affecting clinical outcomes. More mature data are needed to better estimate cost-effectiveness in this setting.

Comparison of Glecaprevir/Pibrentasvir and Sofosbuvir/Ledipasvir in Patients with Hepatitis C Virus Genotype 1 and 2 in South Korea.

Background/Aims: This study compared the effectiveness and safety of glecaprevir/pibrentasvir (GLE/PIB) and sofosbuvir/ledipasvir (SOF/LDV) in real-life clinical practice. Methods: The data from genotype 1 or 2 chronic hepatitis C patients treated with GLE/PIB or sofosbuvir + ribavirin or SOF/LDV in South Korea were collected retrospectively. The analysis included the treatment completion rate, sustained virologic response at 12 weeks (SVR12) test rate, treatment effectiveness, and adverse events. Results: Seven hundred and eighty-two patients with genotype 1 or 2 chronic hepatitis C who were treated with GLE/PIB (n=575) or SOF/LDV (n=207) were included in this retrospective study. The baseline demographic and clinical characteristics revealed significant statistical differences in age, genotype, ascites, liver cirrhosis, and hepatocellular carcinoma between the GLE/PIB and SOF/LDV groups. Twenty-two patients did not complete the treatment protocol. The treatment completion rate was high for both regimens without statistical significance (97.7% vs. 95.7%, p=0.08). The overall SVR12 of intention-to-treat analysis was 81.2% vs. 80.7% without statistical significance (p=0.87). The overall SVR12 of per protocol analysis was 98.7% vs. 100% without statistical significance (p=0.14). Six patients treated with GLE/PIB experienced treatment failure. They were all male, genotype 2, and showed a negative hepatitis C virus RNA level at the end of treatment. Two patients treated with GLE/PIB stopped medication because of fever and abdominal discomfort. Conclusions: Both regimens had similar treatment completion rates, effectiveness, and safety profiles. Therefore, the SOF/LDV regimen can also be considered a viable DAA for the treatment of patients with genotype 1 or 2 chronic hepatitis C.

An angiogenesis-associated gene-based signature predicting prognosis and immunotherapy efficacy of head and neck squamous cell carcinoma patients.

OBJECTIVES: To develop a model that can assist in the diagnosis and prediction of prognosis for head and neck squamous cell carcinoma (HNSCC). MATERIALS AND METHODS: Data from TCGA and GEO databases were used to generate normalized gene expression data. Consensus Cluster Plus was used for cluster analysis and the relationship between angiogenesis-associated gene (AAG) expression patterns, clinical characteristics and survival was examined. Support vector machine (SVM) and least absolute shrinkage and selection operator (LASSO) analyzes and multiple logistic regression analyzes were performed to determine the diagnostic model, and a prognostic nomogram was constructed using univariate and multivariate Cox regression analyses. ESTIMATE, XCELL, TIMER, QUANTISEQ, MCPCOUNTER, EPIC, CIBERSORT-ABS, CIBERSORT algorithms were used to assess the immune microenvironment of HNSCC patients. In addition, gene set enrichment analysis, treatment sensitivity analysis, and AAGs mutation studies were performed. Finally, we also performed immunohistochemistry (IHC) staining in the tissue samples. RESULTS: We classified HNSCC patients into subtypes based on differences in AAG expression from TCGA and GEO databases. There are differences in clinical features, TME, and immune-related gene expression between two subgroups. We constructed a HNSCC diagnostic model based on nine AAGs, which has good sensitivity and specificity. After further screening, we constructed a prognostic risk signature for HNSCC based on six AAGs. The constructed risk score had a good independent prognostic significance, and it was further constructed into a prognostic nomogram together with age and stage. Different prognostic risk groups have differences in immune microenvironment, drug sensitivity, gene enrichment and gene mutation. CONCLUSION: We have constructed a diagnostic and prognostic model for HNSCC based on AAG, which has good performance. The constructed prognostic risk score is closely related to tumor immune microenvironment and immunotherapy response.

Intervention treatment reducing cellular senescence inhibits tubulointerstitial fibrosis in diabetic mice following acute kidney injury.

Senescence of kidney tubules leads to tubulointerstitial fibrosis (TIF). Proximal tubular epithelial cells undergo stress-induced senescence during diabetes and episodes of acute kidney injury (AKI), and combining these injuries promotes the progression of diabetic kidney disease (DKD). Since TIF is crucial to progression of DKD, we examined the therapeutic potential of targeting senescence with a senolytic drug (HSP90 inhibitor) and/or a senostatic drug (ASK1 inhibitor) in a model of TIF in which AKI is superimposed on diabetes. After 8 weeks of streptozotocin-induced diabetes, mice underwent bilateral clamping of renal pedicles to induce mild AKI, followed by 28 days of reperfusion. Groups of mice (n=10-12) received either vehicle, HSP90 inhibitor (alvespimycin), ASK1 inhibitor (GS-444217), or both treatments. Vehicle-treated mice displayed tubular injury at day 3 and extensive tubular cell senescence at day 10, which remained unresolved at day 28. Markers of senescence (Cdkn1a and Cdkn2a), inflammation (Cd68, Tnf, and Ccl2), and TIF (Col1a1, Col4a3, α-Sma/Acta2, and Tgfb1) were elevated at day 28, coinciding with renal function impairment. Treatment with alvespimycin alone reduced kidney senescence and levels of Col1a1, Acta2, Tgfb1, and Cd68; however, further treatment with GS-444217 also reduced Col4a3, Tnf, Ccl2, and renal function impairment. Senolytic therapy can inhibit TIF during DKD, but its effectiveness can be improved by follow-up treatment with a senostatic inhibitor, which has important implications for treating progressive DKD.

Mechanisms of Resistance to Tyrosine Kinase Inhibitors in ROS1 Fusion-Positive Nonsmall Cell Lung Cancer.

BACKGROUND: ROS1 fusion-positive (ROS1+) nonsmall cell lung cancer (NSCLC) patients are highly sensitive to tyrosine kinase inhibitor (TKI) treatments. However, acquired TKI resistance remains the major hurdle preventing patients from experiencing prolonged benefits. METHODS: 107 advanced or metastatic ROS1+ NSCLC patients who progressed on crizotinib and lorlatinib were recruited. Tissue and plasma samples were collected at baseline (N = 50), postcrizotinib (N = 91), and postlorlatinib (N = 21), which were all subject to the 139-gene targeted next-generation DNA sequencing. Molecular dynamics modeling was performed to investigate the effects of ROS1 mutations on binding to different TKIs. RESULTS: In patients with postcrizotinib and postlorlatinib samples, an accumulation of on- and off-target resistance alterations after multiple TKI treatments was observed. ROS1 G2032R and MET amplification were the most common on-target and off-target alterations, respectively. Patients with CD74-ROS1 and SLC34A2-ROS1 had longer progression-free survival (PFS) (P < 0.001) and higher rates of resistance mutations (on-target, P = 0.001; off-target, P = 0.077) than other ROS1 fusion variants following crizotinib treatment. Ten distinct on-target resistance mutations were detected after TKI therapies, of which 4 were previously unreported (ROS1 L2010M, G1957A, D1988N, L1982V). Molecular dynamics simulations showed that all 4 mutations were refractory to crizotinib, while G1957A, D1988N, and L1982V were potentially sensitive to lorlatinib and entrectinib. CONCLUSIONS: This study provided a comprehensive portrait of TKI-resistance mechanisms in ROS1+ NSCLC patients. Using in silico simulations of TKI activity, novel secondary mutations that may confer TKI resistance were identified and may support clinical therapeutic decision-making.

An Infant-Type Hemispheric Glioma With SOX5::ALK: A Novel Fusion.

Infant-type hemispheric glioma (IHG) is a rare pediatric brain tumor with variable response to chemotherapy and radiotherapy. Molecular insights into IHG can be useful in identifying potentially active targeted therapy. A male fetus was found to have congenital hydrocephalus at the gestational age of 37 weeks. Fetal MRI showed a 2.6 × 2.0-cm tumor located at the frontal horn of the left lateral ventricle, involving the left basal nuclei and thalamus. Tumor biopsy at the age of 2 days revealed an IHG consisting of spindle tumor cells with strong expression of GFAP and ALK. Targeted RNA sequencing detected a novel fusion gene of SOX5::ALK. After initial chemotherapy with cyclophosphamide, carboplatin, and etoposide for 2 cycles, the tumor size progressed markedly and the patient underwent a subtotal resection of brain tumor followed by treatment with lorlatinib, an ALK tyrosine kinase inhibitor with central nervous system (CNS) activity. After 3 months of treatment, reduction of tumor size was observed. After 14 months of treatment, partial response was achieved, and the infant had normal growth and development. In conclusion, we identified a case of congenital IHG with a novel SOX5::ALK fusion that had progressed after chemotherapy and showed partial response and clinical benefit after treatment with the CNS-active ALK inhibitor lorlatinib.

Detection of antibiotic residues in groundwater with a validated multiresidue UHPLC-MS/MS quantification method.

The occurrence of antibiotic residues in the environment has received considerable attention because of their potential to select for bacterial resistance. The overuse of antibiotics in human medicine and animal production results in antibiotic residues entering the aquatic environment, but concentrations are currently not well determined. This study investigates the occurrence of antibiotics in groundwater in areas strongly related to agriculture and the antibiotic treatment of animals. A multiresidue method was validated according to EU Regulation 2021/808, to allow (semi-)quantitative analysis of 78 antibiotics from 10 different classes: ß-lactams, sulfonamides, tetracyclines, lincosamides, amphenicols, (fluoro)quinolones, macrolides, pleuromutilins, ansamycins and diaminopyrimidines using ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). This method was used to test different storage conditions of these water samples during a stability study over a period of 2 weeks. Sulfonamides, lincosamides and pleuromutilins were the most stable. Degradation was most pronounced for ß-lactam antibiotics, macrolides and ansamycins. To maintain stability, storage of samples at -18 °C is preferred. With the validated method, antibiotic residues were detected in groundwater, sampled from regions associated with intensive livestock farming in Flanders (Belgium). Out of 50 samples, 14% contained at least one residue. Concentrations were low, ranging from < LOD to 0.03 µg/L. Chloramphenicol, oxolinic acid, tetracycline and sulfonamides (sulfadiazine, sulfadoxine, sulfamethazine and sulfisoxazole) were detected. This study presents a new method for the quantification of antibiotic residues, which was applied to investigate the presence of antibiotic residues in groundwater in Flanders.

Comparative efficacy and safety of Sofosbuvir/Velpatasvir and Danoprevir for the treatment of chronic hepatitis C: the real-world data in China.

BACKGROUND: Sofosbuvir/Velpatasvir (Epclusa, ECS) is the first pan-genotype direct-acting antiviral agent (DAA) for hepatitis C virus (HCV) infection, and Danoprevir (DNV) is the first DAA developed by a Chinese local enterprise, which is suitable for combined use with other drugs to treat genotype 1b chronic hepatitis C. However, previous reports have never compared the real-world data of ECS and DNV. PATIENTS AND METHODS: 178 chronic hepatitis C patients were retrospectively recruited, and 94cases were accepted with Sofosbuvir/Velpatasvir ± Ribavirin (ECS group), and others (n = 84 treated with DNV combination therapy (DNV group). The HCV genotype, virological response, adverse effects and some laboratory biochemical indexes were contrasted between above two groups in the real world study. RESULTS: DNV group had significantly lower level of alpha-fetoprotein (AFP), lower rates of decompensated cirrhosis ( P < 0.05). ECS group possessed more 6a (31.91% vs.13.10%) while DNV group was provided with more 1b (48.81% vs. 22.34%) patients. Significantly poor liver function was detected in ECS group at 4-week treatment (ALT and AST) and 12-week follow-up (AST) (all P < 0.05). The SVR12 undetectable rates of both groups were 100%, and no serious event was observed during the treatment and follow-up in both groups. CONCLUSION: In this retrospective real-world study, the efficacy of DNV combined therapy is similar to Sofosbuvir/Velpatasvir ± Ribavirin for chronic HCV infection, and the safety is comparable. DNV based therapy is a promising regimen for chronic hepatitis C.

Real-World Safety and Effectiveness of an 8-Week Regimen of Glecaprevir/Pibrentasvir in Patients with Hepatitis C and Cirrhosis.

INTRODUCTION: In 2019, an 8-week regimen of glecaprevir/ pibrentasvir (GLE/PIB) was FDA-approved for treatment of chronic hepatitis C (HCV) in patients with cirrhosis. We used data from the Chronic Hepatitis Cohort Study (CHeCS) to evaluate treatment response and adverse events among patients with HCV and cirrhosis under routine clinical care. METHODS: Using an intention-to-treat (ITT)/modified ITT (mITT) approach, endpoints were (1) sustained virological response (SVR) at 12 weeks (SVR12) post-treatment; and (2) adverse events (AEs)/serious AEs during treatment. Patients with cirrhosis from two CHeCS sites were included if they were prescribed GLE/PIB from August 2017 to June 2020. Detailed treatment and clinical data were collected. Patient baseline characteristics were described with mean/standard deviation (std) for continuous variables, and proportions for categorical variables. Analyses were propensity score adjusted. The final model retained variables that were significant with p value < 0.05. RESULTS: The ITT sample included 166 patients, with 43, 116, and 7 patients in the 8-week, 12-week, and > 12-week planned treatment groups. Among them, 159 had confirmed SVR (95.8%, LCL 93.2%). The mITT analysis included 160 patients after excluding 6 with unknown HCV RNA results; 159 achieved SVR (99.4%, LCL 98.3%). There were no significant differences in rates of SVR between the 8-week and 12-week regimens in either analysis, nor any association with patient characteristics. SAEs were experienced by 1 patient (2%) in the 8-week group, 7 (5%) in the 12-week group (including one death), and 2 (29%) in the > 12-week group; 4 patients (from the 12-week group) experienced serious AEs or hepatic events that were "likely attributable" to GLE/PIB treatment. CONCLUSION: An 8-week regimen of GLE/PIB is well tolerated and highly effective among US patients with HCV and cirrhosis receiving routine clinical care.

An algorithm for simplified hepatitis C virus treatment with non-specialist care based on nation-wide data from Taiwan.

BACKGROUND: Both European Association for the Study of the Liver (EASL) and American Association for the Study of Liver Diseases and the Infectious Diseases Society of America (AASLD-IDSA) guidelines recommend simplified hepatitis C virus (HCV) treatment with pan-genotypic sofosbuvir/velpatasvir or glecaprevir/pibrentasvir for eligible patients. This observational study used real-world data to assess these regimens' safety in eligible patients and develop an algorithm to identify patients suitable for simplified treatment by non-specialists. METHODS: 7,677 HCV-infected patients from Taiwan Hepatitis C Registry (TACR) who received at least one dose of sofosbuvir/velpatasvir or glecaprevir/pibrentasvir, and fulfilled the EASL/AASLD-IDSA criteria for simplified treatment were analyzed. Multivariate analysis was conducted on patient characteristics and safety data. RESULTS: Overall, 92.8% (7,128/7,677) of patients achieved sustained virological response and only 1.9% (146/7,677) experienced Grades 2-4 laboratory abnormalities in key liver function parameters (alanine aminotransferase, aspartate aminotransferase, and total bilirubin), with only 18 patients (0.23%) experiencing Grades 3-4 abnormalities. Age > 70 years old, presence of hepatocellular carcinoma, total bilirubin > 1.2 mg/dL, estimated glomerular filtration rate < 60 mL/min/1.73 m2, and Fibrosis-4 > 3.25 were associated with higher risks of Grades 2-4 abnormalities. Patients with any of these had an odds of 4.53 times than that of those without in developing Grades 2-4 abnormalities (p < 0.01). CONCLUSIONS: Real-world data from Taiwan confirmed that simplified HCV treatment for eligible patients with pan-genotypic regimens is effective and well tolerated. The TACR algorithm, developed based on this study's results, can further identify patients who can be safely managed by non-specialist care.

Diverse ansamycin derivatives from the marine-derived Streptomyces sp. ZYX-F-97 and their antibacterial activities.

Four new ansamycin derivatives, named 1,19-epithio-geldanamycin A (1), 17-demethoxylherbimycin H (2), herbimycin M (3), and seco-geldanamycin B (4), together with eight known ansamycin analogues (5-12) were isolated from the solid fermentation of marine-derived actinomycete Streptomyces sp. ZYX-F-97. The structures of new compounds were elucidated by extensive spectroscopic analysis as well as nuclear magnetic resonance (NMR) and electronic circular dichroism (ECD) calculations. All the compounds were assayed for their antibacterial activity. Among them, compounds 4, 8, and 12 exhibited remarkable inhibition against Listeria monocytogenes with minimum inhibitory concentrations (MIC) values ranging from 8 µg·mL-1 to 64 µg·mL-1, and displayed moderate inhibition against methicillin-resistant Staphylococcus aureus (MRSA) with MIC value of 64 µg·mL-1. Compounds 4, 8, 9, and 12 showed moderate inhibition activities against both Staphylococcus aureus and Bacillus subtilis with MIC values ranging from 32 µg·mL-1 to 128 µg·mL-1.

Successful application of lorlatinib in a 23-year-old patient with anaplastic lymphoma kinase (ALK)-positive lung cancer and multiple brain metastases.

BACKGROUND: Anaplastic lymphoma kinase (ALK)-positive lung cancer has a better long-term prognosis with ALK-inhibitor than other lung cancers. However, resistance to ALK-inhibitors and the control of metastases in the central nervous system (CNS) remain to be a challenge in the management of ALK-positive lung cancer. CASE: We present the case of a 23-year-old man who developed multiple brain metastases while receiving alectinib treatment for ALK-positive lung cancer. After 3 months of lorlatinib initiation, brain metastases disappeared, and complete response (CR) was maintained. CONCLUSION: While lorlatinib can be used as first line therapy, this drug may be considered as second line or later option for patients with multiple brain metastases if the patient has already been treated with other ALK-inhibitors since lorlatinib is thought to have good CNS penetration. This treatment option should be verified by further research.

Structurally Diverse Macrolactams from an Antarctic Streptomyces Species.

Twelve new polyenic macrolactams, cyclamenols G-R (1 and 3-13), together with the known analogue cyclamenol A (2), were isolated from Streptomyces sp. OUCMDZ-4348. Their structures were elucidated by spectroscopic analysis, quantum chemical calculations, chemical derivatizations, and Mosher's methods. The sequenced genome of OUCMDZ-4348 revealed the putative biosynthetic gene cluster of cyclamenols. It was proposed that the polycyclic natural products, cyclamenols H-R, might be formed from cyclamenols A and G through nonenzymatic intramolecular cycloadditions and oxidative cyclizations.

Efficacy and safety of glecaprevir and pibrentasvir in Saudi patients with chronic hepatitis C virus infection at a major tertiary hospital.

OBJECTIVES: To evaluate the effectiveness and safety of glecaprevir/pibrentasvir (GLE/PIB) in chronic hepatitis C (HCV) patients, and to assess the prescribers' adherence to Food and Drug Administration recommendations on treatment duration. METHODS: A retrospective cohort study was carried out on chronic HCV patients of ≥18 years, with or without cirrhosis, naive or experienced, and with normal kidney function or chronic kidney disease (including dialysis patients) at Prince Sultan Military Medical City in Riyadh, Saudi Arabia, between February 2020 and March 2021. The primary effectiveness end-point was the number and percentage of patients who achieved a sustained virologic response (SVR12), virologic failure, and non-response. Safety was determined considering both serious and non-serious adverse events. RESULTS: A total of 92 patients were enrolled in this study. Among patients, 52 (56.5%) were female, 84 (91.3%) were naive, and 45 (48.9 %) had HCV genotype 4. The SVR12 was achieved in 91 (98.9%, 95% CI: [94-99.8]) patients. Only one patient (1.1%, 95% CI: [0.2-5.9]) developed virologic non-response and there were missing data on virologic failure. Overall, non-serious adverse events were observed in 26 (28.5%) patients, and none of them had serious adverse events that led to treatment discontinuation. Approximately 75% of the patients received an inappropriate treatment duration (12 weeks vs. the recommended 8 weeks) and most (n=40, 58%; p<0.022) of the exceedingly long treatments were prescribed by registrars. CONCLUSION: The GLE/PIB was highly effective and safe in chronic HCV Saudi patients.

HSP90 Inhibition Attenuated Isoflurane-Induced Neurotoxicity in Mice and Human Neuroglioma Cells.

Isoflurane, a widely used inhalation anesthetic in clinical practice, is associated with an increased risk of neuronal injury. Heat shock protein 90 (HSP90) plays a crucial role in maintaining neuronal homeostasis under stress conditions; however, its role during isoflurane exposure remains poorly understood. In this study, we aimed to investigate the protective effects of HSP90 inhibition and explore the regulatory mechanisms underlying these effects during isoflurane exposure. We found that the HSP90 inhibitor 17-N-allylamino-17-demethoxygeldanamycin (17 AAG) has great protective effects in mitigating isoflurane-induced ferroptosis of mouse hippocampus and cultured neuronal cells. We focused on the activity of the crucial protein GPX4 in ferroptosis and found that 17 AAG exerted protective effects, preserving the physiological GPX4 activity under isoflurane exposure; further, 17 AAG restored the protein level of GPX4. Further, we observed that the chaperone-mediated autophagy (CMA) pathway was activated; 17 AAG also mediated GPX4 degradation under isoflurane exposure. Additionally, it interfered with the formation of complexes between HSP90 and Lamp-2a, inhibiting CMA activity, followed by the blockade of GPX4 degradation, further affecting the isoflurane-induced ferroptosis. Based on these findings, we proposed HSP90 inhibition as a protective mechanism against isoflurane-induced ferroptosis in neurons.

Lorlatinib as a first-line treatment of adult patients with anaplastic lymphoma kinase-positive advanced non-small cell lung cancer: Α cost-effectiveness analysis in Greece.

OBJECTIVES: To evaluate the cost-effectiveness of lorlatinib compared to 1st generation anaplastic lymphoma kinase (ALK) TKI crizotinib, and 2nd generation TKIs alectinib and brigatinib, for previously untreated patients with ALK+ advanced Non-Small Cell Lung Cancer (aNSCLC). METHODS: A partitioned survival model was locally adapted from a Greek payer perspective over a lifetime horizon. Clinical, safety and utility data were extracted from literature. Direct medical costs reflecting the year 2023 were included in the analysis (€). Model outcomes were patients' life years (LYs), quality-adjusted life years (QALYs), total costs and incremental cost-effectiveness ratios (ICERs). RESULTS: Total cost per patient with lorlatinib, alectinib, crizotinib, and brigatinib was estimated to be €188,205, €183,343, €75,028, and €145,454 respectively. Lorlatinib appeared to yield more LYs and QALYs gained versus alectinib, crizotinib, and brigatinib. Hence, lorlatinib resulted in ICERs of €4,315 per LY gained and €4,422 per QALY gained compared to alectinib, €34,032 per LY gained and €48,256 per QALY gained versus crizotinib and €16,587 per LY gained and €26,271 per QALY gained compared to brigatinib. CONCLUSION: Lorlatinib provides substantial clinical benefit and appears to be a cost - effective treatment option compared to 1st and 2nd generation TKIs for previously untreated patients with ALK+ aNCSLC in Greece.

Differential network analysis of ROS1 inhibitors reveals lorlatinib polypharmacology through co-targeting PYK2.

Multiple tyrosine kinase inhibitors (TKIs) are often developed for the same indication. However, their relative overall efficacy is frequently incompletely understood and they may harbor unrecognized targets that cooperate with the intended target. We compared several ROS1 TKIs for inhibition of ROS1-fusion-positive lung cancer cell viability, ROS1 autophosphorylation and kinase activity, which indicated disproportionately higher cellular potency of one TKI, lorlatinib. Quantitative chemical and phosphoproteomics across four ROS1 TKIs and differential network analysis revealed that lorlatinib uniquely impacted focal adhesion signaling. Functional validation using pharmacological probes, RNA interference, and CRISPR-Cas9 knockout uncovered a polypharmacology mechanism of lorlatinib by dual targeting ROS1 and PYK2, which form a multiprotein complex with SRC. Rational multi-targeting of this complex by combining lorlatinib with SRC inhibitors exhibited pronounced synergy. Taken together, we show that systems pharmacology-based differential network analysis can dissect mixed canonical/non-canonical polypharmacology mechanisms across multiple TKIs enabling the design of rational drug combinations.

Inhibition of Heat Shock Protein 90 Lowered Intraocular Pressure without Affecting the Production of Aqueous Humor in Rabbits.

INTRODUCTION: Heat shock protein (Hsp) 90 is one of the most abundant proteins in unstressed cells and regulates stability and functional maintenance of client proteins. In ocular tissue, Hsp90 is widely expressed in the cornea and retina and has multiple roles in these tissues. The expression of HSPs was induced in the retinas of glaucomatous patients and laser-induced glaucoma in monkey while their mechanisms remain to be elucidated. For this reason, we tried to elucidate the role of Hsp90 in intraocular pressure (IOP) regulation in rabbits. METHODS: IOP was measured by a pneumatonometer before and after intracameral injection of Hsp90 inhibitors. The aqueous flow rate was measured by fluorophotometry. Trans-epithelial electrical resistance was measured in primary human trabecular meshwork cells. RESULTS: 17-AAG, a specific Hsp90 inhibitor, significantly lowered IOP at concentrations of more than 30 µm in normotensive rabbits. Other Hsp90 inhibitors also significantly lowered IOP in normotensive rabbits at a dose of 100 µm. No reduction of aqueous humor production was observed by injection of 17-AAG in rabbits. Topical administration of pilocarpine tended to attenuate the IOP-lowering effects induced by the Hsp90 inhibitor. No reduction of trans-epithelial electrical resistance was observed by inhibition of Hsp90 in culture cells. CONCLUSIONS: These results indicated that intraocular Hsp90 regulates IOP, and the inhibition of Hsp90 by Hsp90 inhibitor decreases IOP without affecting aqueous humor production in rabbits. Further research in elucidating the mechanism of Hsp90 inhibitors will result in a better understanding of the role of Hsp90 in the regulation of IOP.