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1.
AAPS J ; 26(4): 84, 2024 Jul 15.
Article in English | MEDLINE | ID: mdl-39009791

ABSTRACT

Measurement of anti-drug antibodies (ADA) to assess the incidence of ADA in a clinical trial is a critical step in immunogenicity assessment during the development of a protein therapeutic. We developed novel graphical approaches to illustrate clinical trial ADA data for the PD-L1 inhibitor atezolizumab (Tecentriq) that included a systematic analysis of the impact of the timing of ADA sampling and ADA assay drug tolerance on reported ADA incidence. We found that approaches used across the industry for ADA incidence analysis provide a limited view of immunogenicity in oncology studies, where ADA detection may be confounded by both drug dosage and patient attrition. Moreover, these approaches can miss important temporal information about the immune response. Our results demonstrated that the methodology of ADA assessment for the atezolizumab program was specifically designed to capture most ADA responses to ensure accurate reporting of ADA incidence. We further showed that the use of sparse sampling and/or ADA test methods with insufficient drug tolerance may result in a significant underreporting of ADA incidence. We conclude that the comparison of ADA incidence between different drugs can be highly misleading and that a test method with appropriate sensitivity in the presence of the drug and a clinical sampling scheme that is aligned with ADA responses to a drug is required to accurately report ADA incidence.


Subject(s)
Antibodies, Monoclonal, Humanized , Humans , Antibodies, Monoclonal, Humanized/immunology , Antibodies/immunology , Drug Tolerance/immunology , Immune Checkpoint Inhibitors/immunology
2.
Cancers (Basel) ; 16(13)2024 Jun 30.
Article in English | MEDLINE | ID: mdl-39001489

ABSTRACT

Drug tolerance is a major cause of relapse after cancer treatment. Despite intensive efforts, its molecular basis remains poorly understood, hampering actionable intervention. We report a previously unrecognized signaling mechanism supporting drug tolerance in BRAF-mutant melanoma treated with BRAF inhibitors that could be of general relevance to other cancers. Its key features are cell-intrinsic intracellular Ca2+ signaling initiated by P2X7 receptors (purinergic ligand-gated cation channels) and an enhanced ability for these Ca2+ signals to reactivate ERK1/2 in the drug-tolerant state. Extracellular ATP, virtually ubiquitous in living systems, is the ligand that can initiate Ca2+ spikes via P2X7 channels. ATP is abundant in the tumor microenvironment and is released by dying cells, ironically implicating treatment-initiated cancer cell death as a source of trophic stimuli that leads to ERK reactivation and drug tolerance. Such a mechanism immediately offers an explanation of the inevitable relapse after BRAFi treatment in BRAF-mutant melanoma and points to actionable strategies to overcome it.

3.
Genes (Basel) ; 15(7)2024 Jul 11.
Article in English | MEDLINE | ID: mdl-39062685

ABSTRACT

Lung cancer patients treated with targeted therapies frequently respond well but invariably relapse due to the development of drug resistance. Drug resistance is in part mediated by a subset of cancer cells termed "drug-tolerant persisters" (DTPs), which enter a dormant, slow-cycling state that enables them to survive drug exposure. DTPs also exhibit stem cell-like characteristics, broad epigenetic reprogramming, altered metabolism, and a mutagenic phenotype mediated by adaptive mutability. While several studies have characterised the transcriptional changes that lead to the altered phenotypes exhibited in DTPs, these studies have focused predominantly on protein coding changes. As long non-coding RNAs (lncRNAs) are also implicated in the phenotypes altered in DTPs, it is likely that they play a role in the biology of drug tolerance. In this review, we outline how lncRNAs may contribute to the key characteristics of DTPs, their potential roles in tolerance to targeted therapies, and the emergence of genetic resistance in lung adenocarcinoma.


Subject(s)
Adenocarcinoma of Lung , Drug Resistance, Neoplasm , Lung Neoplasms , RNA, Long Noncoding , Humans , RNA, Long Noncoding/genetics , Lung Neoplasms/genetics , Lung Neoplasms/drug therapy , Lung Neoplasms/pathology , Drug Resistance, Neoplasm/genetics , Adenocarcinoma of Lung/genetics , Adenocarcinoma of Lung/drug therapy , Adenocarcinoma of Lung/pathology , Gene Expression Regulation, Neoplastic/drug effects , Antineoplastic Agents/therapeutic use , Antineoplastic Agents/pharmacology , Drug Tolerance/genetics
4.
ACS Infect Dis ; 2024 Jun 28.
Article in English | MEDLINE | ID: mdl-38940498

ABSTRACT

The ability of pathogenic bacteria to evade antibiotic treatment is an intricate and multifaceted phenomenon. Over the years, treatment failure among patients due to determinants of antimicrobial resistance (AMR) has been the focal point for the research and development of new therapeutic agents. However, the survival of bacteria by persisting under antibiotic stress has largely been overlooked. Bacterial persisters are a subpopulation of sensitive bacterial cells exhibiting a noninheritable drug-tolerant phenotype. They are linked to the recalcitrance of infections in healthcare settings, in turn giving rise to AMR variants. The importance of bacterial persistence in recurring infections has been firmly recognized. Fundamental work over the past decade has highlighted numerous unique tolerance factors contributing to the persister phenotype in many clinically relevant pathogens. This review summarizes contributing factors that could aid in developing new strategies against bacterial antibiotic persisters.

5.
Korean J Pain ; 37(3): 211-217, 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38881281

ABSTRACT

Background: Tolerance to the analgesic effects of opioids and non-steroidal anti-inflammatory drugs (NSAIDs) is a major concern for relieving pain. Thus, it is highly valuable to find new pharmacological strategies for prolonged therapeutic procedures. Biguanide-type drugs such as metformin (MET) are effective for neuroprotection and can be beneficial for addressing opioid tolerance in the treatment of chronic pain. It has been proposed that analgesic tolerance to NSAIDs is mediated by the endogenous opioid system. According to the cross-tolerance between NSAIDs, especially sodium salicylate (SS), and opiates, especially morphine, the objective of this study was to investigate whether MET administration can reduce tolerance to the anti-nociceptive effects of SS. Methods: Fifty-six male Wistar rats were used in this research (weight 200-250 g). For induction of tolerance, SS (300 mg/kg) was injected intraperitoneally for 7 days. During the examination period, animals received MET at doses of 50, 75, or 100 mg/kg for 7 days to evaluate the development of tolerance to the analgesic effect of SS. The hot plate test was used to evaluate the drugs' anti-nociceptive properties. Results: Salicylate injection significantly increased hot plate latency as compared to the control group, but the total analgesic effect of co-treatment with SS + Met50 was stronger than the SS group. Furthermore, the effect of this combination undergoes less analgesic tolerance over time. Conclusions: It can be concluded that MET can reduce the analgesic tolerance that is induced by repeated intraperitoneal injections of SS in Wister rats.

6.
EMBO Mol Med ; 16(7): 1603-1629, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38886591

ABSTRACT

Despite clinical benefits of tyrosine kinase inhibitors (TKIs) in cancer, most tumors can reactivate proliferation under TKI therapy. Here we present transcriptional profiling of HER2+ breast cancer cells transitioning from dormant drug tolerant cells to re-proliferating cells under continuous HER2 inhibitor (HER2i) therapy. Focusing on phosphatases, expression of dual-specificity phosphatase DUSP6 was found inhibited in dormant cells, but strongly induced upon regrowth. DUSP6 expression also selectively associated with poor patient survival in HER2+ breast cancers. DUSP6 overexpression conferred apoptosis resistance, whereas its pharmacological blockade prevented therapy tolerance development under HER2i therapy. DUSP6 targeting also synergized with clinically used HER2i combination therapies. Mechanistically DUSP6 is a positive regulator of HER3 expression, and its impact on HER2i tolerance was mediated by neuregulin-HER3 axis. In vivo, genetic targeting of DUSP6 reduced tumor growth in brain metastasis model, whereas its pharmacological targeting induced synthetic lethal therapeutic effect in combination with HER2i. Collectively this work demonstrates that DUSP6 drives escape from HER2i-induced dormancy, and that DUSP6 is a druggable target to overcome HER3-driven TKI resistance.


Subject(s)
Breast Neoplasms , Dual Specificity Phosphatase 6 , Receptor, ErbB-2 , Receptor, ErbB-3 , Dual Specificity Phosphatase 6/metabolism , Dual Specificity Phosphatase 6/genetics , Humans , Breast Neoplasms/drug therapy , Breast Neoplasms/pathology , Breast Neoplasms/metabolism , Breast Neoplasms/genetics , Female , Receptor, ErbB-2/metabolism , Animals , Receptor, ErbB-3/metabolism , Receptor, ErbB-3/genetics , Receptor, ErbB-3/antagonists & inhibitors , Cell Line, Tumor , Mice , Drug Resistance, Neoplasm/drug effects , Antineoplastic Agents/pharmacology , Antineoplastic Agents/therapeutic use , Protein Kinase Inhibitors/pharmacology
7.
Front Cell Dev Biol ; 12: 1394140, 2024.
Article in English | MEDLINE | ID: mdl-38887520

ABSTRACT

Leukemia is a life-threatening malignant tumor of the hematopoietic system. Currently, the main treatment modalities are chemotherapy and hematopoietic stem cell transplantation. However, increased drug resistance due to decreased sensitivity of leukemia cells to chemotherapeutic drugs presents a major challenge in current treatments. Autophagy-associated proteins involved in autophagy initiation have now been shown to be involved in the development of various types of leukemia cells and are associated with drug resistance. Therefore, this review will explore the roles of autophagy-related proteins involved in four key autophagic processes: induction of autophagy and phagophore formation, phagophore extension, and autophagosome formation, on the development of various types of leukemias as well as drug resistance. Autophagy may become a promising therapeutic target for treating leukemia.

8.
Infect Immun ; 92(6): e0010324, 2024 Jun 11.
Article in English | MEDLINE | ID: mdl-38722168

ABSTRACT

Candida auris is an opportunistic fungal pathogen with high mortality rates which presents a clear threat to public health. The risk of C. auris infection is high because it can colonize the body, resist antifungal treatment, and evade the immune system. The genetic mechanisms for these traits are not well known. Identifying them could lead to new targets for new treatments. To this end, we present an analysis of the genetics and gene expression patterns of C. auris carbon metabolism, drug resistance, and macrophage interaction. We chose to study two C. auris isolates simultaneously, one drug sensitive (B11220 from Clade II) and one drug resistant (B11221 from Clade III). Comparing the genomes, we confirm the previously reported finding that B11220 was missing a 12.8 kb region on chromosome VI. This region contains a gene cluster encoding proteins related to alternative sugar utilization. We show that B11221, which has the gene cluster, readily assimilates and utilizes D-galactose and L-rhamnose as compared to B11220, which harbors the deletion. B11221 exhibits increased adherence and drug resistance compared to B11220 when grown in these sugars. Transcriptomic analysis of both isolates grown on glucose or galactose showed that the gene cluster was upregulated when grown on D-galactose. These findings reinforce growing evidence of a link between metabolism and drug tolerance. B11221 resists phagocytosis by macrophages and exhibits decreased ß-1,3-glucan exposure, a key determinant that allows Candida to evade the host immune system, as compared to B11220. In a transcriptomic analysis of both isolates co-cultured with macrophages, we find upregulation of genes associated with transport and transcription factors in B11221. Our studies show a positive correlation between membrane composition and immune evasion, alternate sugar utilization, and drug tolerance in C. auris.


Subject(s)
Antifungal Agents , Candida auris , Virulence/genetics , Candida auris/genetics , Candida auris/drug effects , Antifungal Agents/pharmacology , Candidiasis/microbiology , Candidiasis/immunology , Drug Resistance, Fungal/genetics , Genome, Fungal , Humans , Macrophages/microbiology , Macrophages/immunology , Gene Expression Regulation, Fungal , Gene Expression Profiling , Animals
9.
J Cell Mol Med ; 28(9): e18329, 2024 May.
Article in English | MEDLINE | ID: mdl-38693863

ABSTRACT

Therapy failure with the tyrosine kinase inhibitor (TKI) sunitinib remains a great challenge in metastatic renal cell carcinoma (mRCC). Growing evidence indicates that the tumour subpopulation can enter a transient, non-mutagenic drug-tolerant state to endure the treatment underlying the minimal residual disease and tumour relapse. Drug tolerance to sunitinib remains largely unexplored in RCC. Here, we show that sunitinib-tolerant 786-O/S and Caki-2/S cells are induced by prolonged drug treatment showing reduced drug sensitivity, enhanced clonogenicity, and DNA synthesis. Sunitinib-tolerance developed via dynamic processes, including (i) engagement of c-MET and AXL pathways, (ii) alteration of stress-induced p38 kinase and pro-survival BCL-2 signalling, (iii) extensive actin remodelling, which was correlated with activation of focal adhesion proteins. Remarkably, the acute drug response in both sensitive and sunitinib-tolerant cell lines led to dramatic fine-tuning of the actin-cytoskeleton and boosted cellular migration and invasion, indicating that the drug-response might depend on cell state transition rather than pre-existing mutations. The drug-tolerant state was transiently acquired, as the cells resumed initial drug sensitivity after >10 passages under drug withdrawal, reinforcing the concept of dynamic regulation and phenotypic heterogeneity. Our study described molecular events contributing to the reversible switch into sunitinib-tolerance, providing possible novel therapeutic opportunities in RCC.


Subject(s)
Carcinoma, Renal Cell , Cell Movement , Drug Resistance, Neoplasm , Kidney Neoplasms , Sunitinib , Humans , Carcinoma, Renal Cell/drug therapy , Carcinoma, Renal Cell/genetics , Carcinoma, Renal Cell/pathology , Carcinoma, Renal Cell/metabolism , Sunitinib/pharmacology , Sunitinib/therapeutic use , Cell Line, Tumor , Kidney Neoplasms/drug therapy , Kidney Neoplasms/genetics , Kidney Neoplasms/pathology , Kidney Neoplasms/metabolism , Drug Resistance, Neoplasm/genetics , Drug Resistance, Neoplasm/drug effects , Cell Movement/drug effects , Receptor Protein-Tyrosine Kinases/metabolism , Receptor Protein-Tyrosine Kinases/genetics , Signal Transduction/drug effects , Proto-Oncogene Proteins c-met/metabolism , Proto-Oncogene Proteins c-met/genetics , Antineoplastic Agents/pharmacology , Proto-Oncogene Proteins c-bcl-2/metabolism , Proto-Oncogene Proteins c-bcl-2/genetics , Axl Receptor Tyrosine Kinase , Pyrroles/pharmacology , Proto-Oncogene Proteins/metabolism , Proto-Oncogene Proteins/genetics , Cell Proliferation/drug effects , Indoles/pharmacology
10.
Pharmacol Res ; 204: 107208, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38729587

ABSTRACT

Cancer cell line is commonly used for discovery and development of anti-cancer drugs. It is generally considered that drug response remains constant for a certain cell line due to the identity of genetics thus protein patterns. Here, we demonstrated that cancer cells continued dividing even after reaching confluence, in that the proteomics was changed continuously and dramatically with strong relevance to cell division, cell adhesion and cell metabolism, indicating time-dependent intrinsically reprogramming of cells during expansion. Of note, the inhibition effect of most anti-cancer drugs was strikingly attenuated in culture cells along with cell expansion, with the strongest change at the third day when cells were still expanding. Profiling of an FDA-approved drug library revealed that attenuation of response with cell expansion is common for most drugs, an exception was TAK165 that was a selective inhibitor of mitochondrial respiratory chain complex I. Finally, we screened a panel of natural products and identified four pentacyclic triterpenes as selective inhibitors of cancer cells under prolonged growth. Taken together, our findings underscore that caution should be taken in evaluation of anti-cancer drugs using culture cells, and provide agents selectively targeting overgrowth cancer cells.


Subject(s)
Antineoplastic Agents , Cell Proliferation , Proteomics , Humans , Antineoplastic Agents/pharmacology , Cell Line, Tumor , Cell Proliferation/drug effects , Neoplasms/drug therapy , Neoplasms/metabolism , Neoplasms/pathology , Time Factors , Biological Products/pharmacology , Pentacyclic Triterpenes/pharmacology
11.
FEBS J ; 2024 Apr 27.
Article in English | MEDLINE | ID: mdl-38676952

ABSTRACT

The emergence of antimicrobial resistance (AMR) across bacterial pathogens presents a serious threat to global health. This threat is further exacerbated in tuberculosis (TB), mainly due to a protracted treatment regimen involving a combination of drugs. A diversity of factors contributes to the emergence of drug resistance in TB, which is caused by the pathogen Mycobacterium tuberculosis (Mtb). While the traditional genetic mutation-driven drug resistance mechanisms operate in Mtb, there are also several additional unique features of drug resistance in this pathogen. Research in the past decade has enriched our understanding of such unconventional factors as efflux pumps, bacterial heterogeneity, metabolic states, and host microenvironment. Given that the discovery of new antibiotics is outpaced by the emergence of drug resistance patterns displayed by the pathogen, newer strategies for combating drug resistance are desperately needed. In the context of TB, such approaches include targeting the efflux capability of the pathogen, modulating the host environment to prevent bacterial drug tolerance, and activating the host anti-mycobacterial pathways. In this review, we discuss the traditional mechanisms of drug resistance in Mtb, newer understandings and the shaping of a set of unconventional approaches to target both the emergence and treatment of drug resistance in TB.

12.
Article in English | MEDLINE | ID: mdl-38476122

ABSTRACT

Background: The clinical efficacy of roflumilast, an oral phosphodiesterase-4 inhibitor, has been demonstrated in patients with severe chronic obstructive pulmonary disease (COPD). However, roflumilast has shown frequent adverse drug reactions (ADRs). This study was performed to investigate the dosing strategy that will improve adherence to roflumilast in COPD. Methods: We conducted a systematic review and meta-analysis using PubMed, Embase, and Cochrane Central Register. The dosing strategy for roflumilast was classified into a dose-escalation group and a low-dose group. We investigated clinical outcomes according to dosing strategy. Results: Five clinical trials involving 2424 patients were included. Both the dose-escalation and the low-dose groups showed a decrease in discontinuation rate compared to the standard dosing group for roflumilast (risk ratio [RR], 0.81; 95% confidence interval [CI], 0.67-0.97; P = 0.02 and RR, 0.62; 95% CI, 0.48-0.80; P < 0.01, respectively). In the two strategies, the pooled proportions of discontinuation were 27.9% and 11.7%, respectively. Although the pooled proportion of any ADR was not statistically decreased in the two strategies, diarrhea was significantly reduced in the low-dose group compared to the standard group (RR, 0.58; 95% CI, 0.42-0.82; P < 0.01). The pooled incidence of acute exacerbations was similar between the low-dose and the standard groups (22.9% and 20.1%, respectively; P = 0.27). Conclusion: Our findings show that the two alternative dosing strategies might have the benefit of improving adherence to roflumilast in COPD. Further large-scale trials are required to support our findings.

13.
Trends Cancer ; 10(5): 393-406, 2024 May.
Article in English | MEDLINE | ID: mdl-38429144

ABSTRACT

The persistence of drug-sensitive tumors poses a significant challenge in cancer treatment. The concept of bacterial persisters, which are a subpopulation of bacteria that survive lethal antibiotic doses, is frequently used to compare to residual disease in cancer. Here, we explore drug tolerance of cancer cells and bacteria. We highlight the fact that bacteria, in contrast to cancer cells, have been selected for survival at the population level and may therefore possess contingency mechanisms that cancer cells lack. The precise mechanisms of drug-tolerant cancer cells and bacterial persisters are still being investigated. Undoubtedly, by understanding common features as well as differences, we, in the cancer field, can learn from microbiology to find strategies to eradicate persisting cancer cells.


Subject(s)
Anti-Bacterial Agents , Bacteria , Neoplasms , Humans , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Antineoplastic Agents/pharmacology , Antineoplastic Agents/therapeutic use , Bacteria/drug effects , Drug Resistance, Neoplasm/drug effects , Neoplasm, Residual , Neoplasms/drug therapy , Neoplasms/pathology
14.
J Cannabis Res ; 6(1): 3, 2024 Feb 03.
Article in English | MEDLINE | ID: mdl-38308382

ABSTRACT

BACKGROUND: Acute cannabis use has been demonstrated to slow reaction time and affect decision-making and short-term memory. These effects may have utility in identifying impairment associated with recent use. However, these effects have not been widely investigated among individuals with a pattern of daily use, who may have acquired tolerance. The purpose of this study was to examine the impact of tolerance to cannabis on the acute effects as measured by reaction time, decision-making (gap acceptance), and short-term memory. METHODS: Participants (ages 25-45) completed a tablet-based (iPad) test battery before and approximately 60 min after smoking cannabis flower. The change in performance from before to after cannabis use was compared across three groups of cannabis users: (1) occasional use (n = 23); (2) daily use (n = 31); or (3) no current use (n = 32). Participants in the occasional and daily use group self-administered ad libitum, by smoking or vaping, self-supplied cannabis flower with a high concentration of total THC (15-30%). RESULTS: The occasional use group exhibited decrements in reaction time (slowed) and short-term memory (replicated fewer shapes) from before to after cannabis use, as compared to the no-use group. In the gap acceptance task, daily use participants took more time to complete the task post-smoking cannabis as compared to those with no use or occasional use; however, the level of accuracy did not significantly change. CONCLUSIONS: The findings are consistent with acquired tolerance to certain acute psychomotor effects with daily cannabis use. The finding from the gap acceptance task which showed a decline in speed but not accuracy may indicate a prioritization of accuracy over response time. Cognitive and psychomotor assessments may have utility for identifying impairment associated with recent cannabis use.

15.
Seizure ; 117: 44-49, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38308908

ABSTRACT

OBJECTIVE: Perampanel (PER) is a new anti-seizure medication (ASM) with a novel mechanism of action. This study aimed to determine the efficacy and safety of PER when added to monotherapy in children and adolescents (age, 4-18 years) with epilepsy. METHOD: A multicenter prospective observational study was performed on children and adolescents (age, 4-18 years) with epilepsy who did not respond to ASM monotherapy between July 2021 and October 2022. PER was used as the first add-on therapy for the enrolled patients. Seizure-free rate, response rate, inefficacy rate, and drug retention rate were the main observation indicators during the 6 months of treatment. The patients were grouped based on treatment efficacy, and factors affecting efficacy were statistically analyzed. Adverse reactions were also recorded. RESULTS: In this study, 93 patients with epilepsy were enrolled; among them, 9 patients were lost to follow-up (attrition rate, 9.7 %), and 84 were included in the analysis. Five patients with unknown efficacy discontinued taking PER early due to intolerable adverse reactions, and 79 patients (48 males, 31 females; mean age, 11.0 ± 3.9 years) finally remained. Genetic epilepsy and structural epilepsy were found in 22 patients and 36 patients, respectively. The mean duration of epilepsy history at the time of PER initiation was 4.0 ± 3.8 years, and the mean maintenance dosage of add-on PER was 4.5 ± 1.8 mg/day (equivalent to 0.14 ± 0.07 mg/kg/day). Among the 79 patients, 28 patients were diagnosed with epilepsy syndrome, including 13 patients having self-limited epilepsy with centrotemporal spikes, among whom 9 patients were seizure-free after adding PER during the 6-month follow-up (seizure-free rate, 69.2 %). For these 79 patients, the seizure-free, response, and retention rates at the end of follow-up were 45.6 %, 74.7 %, and 82.1 %, respectively. Among the 84 patients included in the analyses, adverse reactions occurred in 20 patients, mainly dizziness (8 patients), somnolence (6 patients), and irritability (4 patients), and 4 patients developed two adverse reactions simultaneously. Univariate analyses revealed statistically significant differences in efficacy between groups with structural and non-structural epilepsy and between groups with different baseline concomitant ASMs, suggesting that these factors affected the efficacy of PER as the first add-on therapy. CONCLUSION: The overall response rate of PER as the first add-on therapy for children and adolescents with epilepsy who were followed up for 6 months was 74.7 %, indicating a relatively favorable safety and tolerability profile. The group of the baseline concomitant ASM administered and the etiological classification of epilepsy as either structural or non-structural were the factors influencing the efficacy of PER as the first add-on therapy.


Subject(s)
Anticonvulsants , Drug Therapy, Combination , Epilepsy , Nitriles , Pyridones , Humans , Child , Male , Female , Anticonvulsants/administration & dosage , Anticonvulsants/adverse effects , Pyridones/adverse effects , Pyridones/administration & dosage , Pyridones/therapeutic use , Adolescent , Child, Preschool , Prospective Studies , Epilepsy/drug therapy , Treatment Outcome
16.
Res Sq ; 2024 Apr 16.
Article in English | MEDLINE | ID: mdl-38410476

ABSTRACT

Clinical data revealed that KRAS mutant tumors, while initially sensitive to treatment, rapidly bypass KRAS dependence to acquire a drug-tolerant phenotype. However, the mechanisms underlying the transition from a drug-sensitive to a drug-tolerant state still elude us. Here, we show that global chromatin reorganization is a recurrent and specific feature of KRAS-dependent cells that tolerated KRAS silencing. We show that KRAS-dependent cells undergo G0/G1 cell cycle arrest after KRAS silencing, presenting a transcriptomic signature of quiescence. Proteomic analysis showed upregulated chromatin-associated proteins and transcription-associated biological processes. Accordingly, these cells shifted euchromatin/heterochromatin states, gained topologically associating domains, and altered the nanoscale physical organization of chromatin, more precisely by downregulating chromatin packing domains, a feature associated with the induction of quiescence. In addition, they also accumulated transcriptional alterations over time leading to a diversification of biological processes, linking chromatin alterations to transcriptional performance. Overall, our observations pinpoint a novel molecular mechanism of tolerance to KRAS oncogenic loss driven not by specific gene alterations but by global reorganization of genomic information, in which cells transition chromatin domain structure towards a more quiescent state and gain transcriptional reprogramming capacity.

17.
Biochimie ; 220: 67-83, 2024 May.
Article in English | MEDLINE | ID: mdl-38168626

ABSTRACT

In the ongoing battle against antimicrobial resistance, phenotypic drug tolerance poses a formidable challenge. This adaptive ability of microorganisms to withstand drug pressure without genetic alterations further complicating global healthcare challenges. Microbial populations employ an array of persistence mechanisms, including dormancy, biofilm formation, adaptation to intracellular environments, and the adoption of L-forms, to develop drug tolerance. Moreover, molecular mechanisms like toxin-antitoxin modules, oxidative stress responses, energy metabolism, and (p)ppGpp signaling contribute to this phenomenon. Understanding these persistence mechanisms is crucial for predicting drug efficacy, developing strategies for chronic bacterial infections, and exploring innovative therapies for refractory infections. In this comprehensive review, we dissect the intricacies of drug tolerance and persister formation, explore their role in acquired drug resistance, and highlight emerging therapeutic approaches to combat phenotypic drug tolerance. Furthermore, we outline the future landscape of interventions for persistent bacterial infections.


Subject(s)
Anti-Bacterial Agents , Bacteria , Humans , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Bacteria/drug effects , Bacteria/genetics , Bacteria/metabolism , Bacterial Infections/drug therapy , Bacterial Infections/microbiology , Drug Tolerance , Drug Resistance, Bacterial , Oxidative Stress/drug effects , Biofilms/drug effects , Biofilms/growth & development , Phenotype
18.
Tuberculosis (Edinb) ; 145: 102479, 2024 03.
Article in English | MEDLINE | ID: mdl-38262199

ABSTRACT

Persistence of Mycobacterium tuberculosis (Mtb) is one of the challenges to successful treatment of tuberculosis (TB). In vitro models of non-replicating Mtb are used to test the efficacy of new molecules against Mtb persisters. The H37Ra strain is attenuated for growth in macrophages and mice. We validated H37Ra-infected immunocompetent mice for testing anti-TB molecules against slow/non-replicating Mtb in vivo. Swiss mice were infected intravenously with H37Ra and monitored for CFU burden and histopathology for a period of 12 weeks. The bacteria multiplied at a slow pace reaching a maximum load of ∼106 in 8-12 weeks depending on the infection dose, accompanied by time and dose-dependent histopathological changes in the lungs. Surprisingly, four-weeks of treatment with isoniazid-rifampicin-ethambutol-pyrazinamide combination caused only 0.4 log10 and 1 log10 reduction in CFUs in lungs and spleen respectively. The results show that ∼40 % of the H37Ra bacilli in lungs are persisters after 4 weeks of anti-TB therapy. Isoniazid/rifampicin monotherapy also showed similar results. A combination of bedaquiline and isoniazid reduced the CFU counts to <200 (limit of detection), compared to ∼5000 CFUs by isoniazid alone. The study demonstrates an in vivo model of Mtb persisters for testing new leads using a BSL-2 strain.


Subject(s)
Mycobacterium tuberculosis , Tuberculosis , Animals , Mice , Isoniazid/pharmacology , Isoniazid/therapeutic use , Rifampin/pharmacology , Rifampin/therapeutic use , Tuberculosis/drug therapy , Tuberculosis/microbiology , Pyrazinamide/therapeutic use , Antitubercular Agents/pharmacology , Antitubercular Agents/therapeutic use
19.
J Thorac Dis ; 15(11): 5913-5921, 2023 Nov 30.
Article in English | MEDLINE | ID: mdl-38090320

ABSTRACT

Background: The role of combination treatments with two antifibrotic agents, pirfenidone and nintedanib, has been not established in idiopathic pulmonary fibrosis (IPF). This study was performed to investigate the safety and tolerability of combination antifibrotic treatment in patients with IPF. Methods: We conducted a proportional meta-analysis and searched PubMed, EMBASE, and the Cochrane Central Register for relevant clinical trials. The primary outcome was the proportion of discontinuation of combination treatment over the treatment period. We also examined the pooled proportions of serious and any adverse drug reactions (ADRs). Results: Four clinical trials involving 191 patients were analyzed. In pooled estimates, 29% of patients discontinued treatment during the study period [95% confidence interval (CI): 17-41%, I2=65.42%]. The pooled proportions of serious and any ADRs were 10% (95% CI: 1-19%; I2=79.13%) and 82% (95% CI: 75-90%; I2=39.20%), respectively. During the follow-up period, gastrointestinal symptoms were the most frequent ADR. Acute exacerbation (AE) of IPF was reported in 7.0% of patients. Conclusions: Our findings showed relatively frequent incidence of discontinuation and ADRs for combination therapy in IPF. Further large-scale, randomized, controlled trials are needed to support our results because of the methodological limitations of the included trials and a scarcity of trials for analysis.

20.
Aging (Albany NY) ; 15(24): 14733-14748, 2023 12 29.
Article in English | MEDLINE | ID: mdl-38159250

ABSTRACT

BACKGROUND: Anoikis is a speed-limited procedure to inhibit tumor metastasis during epithelial-mesenchymal transition (EMT). Previous studies have explored anoikis-related genes (ARG) in predicting prognosis and distinguishing tumoral immunity in many types of cancer. However, the role of ARGs in regulating NK cell exhaustion (NKE) and in predicting chemotherapy sensitivity is not clear. Therefore, it is necessary to work on it. METHODS: Gene expression profiles and clinical features are collected from TCGA and GEO, and data analysis is performed in R4.2.0. RESULTS: The ARGs-based no-supervised learning algorithm identifies three ARG subgroups, amongst which the prognosis is different. WCGNA and Artificial intelligence (AI) are applied to construct an NKE-related drug sensitivity stratification and prognosis identification model in digestive system cancer. Pathways association analysis screens out GLI2 is a key gene in regulating NKE by non-classic Hedgehog signaling (GLI2/TGF-ß/IL6). In vitro experiments show that down-regulation of GLI2 enhances the CAPE-mediated cell toxicity and accompanies with down-regulation of PD-L1, tumor-derive IL6, and snial1 whereas the expression of cleaved caspas3, cleaved caspase4, cleaved PARP, and E-cadherin are up-regulated in colorectal cancer. Co-culture experiments show that GLI2- decreased colorectal tumor cells lead to down-regulation of TIM-3 and PD1 in NK cells, which are restored by TGF-bate active protein powder. Besides, the Elisa assay shows that GLI2-decreased colorectal tumor cells lead to up-regulation of IFN-gamma in NK cells.


Subject(s)
Anoikis , Colorectal Neoplasms , Hedgehog Proteins , Zinc Finger Protein Gli2 , Humans , Anoikis/genetics , Artificial Intelligence , Cell Line, Tumor , Colorectal Neoplasms/genetics , Hedgehog Proteins/genetics , Hedgehog Proteins/metabolism , Interleukin-6 , Nuclear Proteins/genetics , Transforming Growth Factor beta , Zinc Finger Protein Gli2/genetics
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