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1.
N Engl J Med ; 382(1): 41-50, 2020 01 02.
Article in English | MEDLINE | ID: mdl-31751012

ABSTRACT

BACKGROUND: Osimertinib is a third-generation, irreversible tyrosine kinase inhibitor of the epidermal growth factor receptor (EGFR-TKI) that selectively inhibits both EGFR-TKI-sensitizing and EGFR T790M resistance mutations. A phase 3 trial compared first-line osimertinib with other EGFR-TKIs in patients with EGFR mutation-positive advanced non-small-cell lung cancer (NSCLC). The trial showed longer progression-free survival with osimertinib than with the comparator EGFR-TKIs (hazard ratio for disease progression or death, 0.46). Data from the final analysis of overall survival have not been reported. METHODS: In this trial, we randomly assigned 556 patients with previously untreated advanced NSCLC with an EGFR mutation (exon 19 deletion or L858R allele) in a 1:1 ratio to receive either osimertinib (80 mg once daily) or one of two other EGFR-TKIs (gefitinib at a dose of 250 mg once daily or erlotinib at a dose of 150 mg once daily, with patients receiving these drugs combined in a single comparator group). Overall survival was a secondary end point. RESULTS: The median overall survival was 38.6 months (95% confidence interval [CI], 34.5 to 41.8) in the osimertinib group and 31.8 months (95% CI, 26.6 to 36.0) in the comparator group (hazard ratio for death, 0.80; 95.05% CI, 0.64 to 1.00; P = 0.046). At 3 years, 79 of 279 patients (28%) in the osimertinib group and 26 of 277 (9%) in the comparator group were continuing to receive a trial regimen; the median exposure was 20.7 months and 11.5 months, respectively. Adverse events of grade 3 or higher were reported in 42% of the patients in the osimertinib group and in 47% of those in the comparator group. CONCLUSIONS: Among patients with previously untreated advanced NSCLC with an EGFR mutation, those who received osimertinib had longer overall survival than those who received a comparator EGFR-TKI. The safety profile for osimertinib was similar to that of the comparator EGFR-TKIs, despite a longer duration of exposure in the osimertinib group. (Funded by AstraZeneca; FLAURA ClinicalTrials.gov number, NCT02296125.).


Subject(s)
Acrylamides/therapeutic use , Aniline Compounds/therapeutic use , Carcinoma, Non-Small-Cell Lung/drug therapy , Lung Neoplasms/drug therapy , Protein Kinase Inhibitors/therapeutic use , Acrylamides/adverse effects , Aged , Aniline Compounds/adverse effects , Antineoplastic Agents/adverse effects , Antineoplastic Agents/therapeutic use , Carcinoma, Non-Small-Cell Lung/genetics , Carcinoma, Non-Small-Cell Lung/mortality , Double-Blind Method , ErbB Receptors/antagonists & inhibitors , ErbB Receptors/genetics , Erlotinib Hydrochloride/therapeutic use , Female , Gefitinib/therapeutic use , Humans , Kaplan-Meier Estimate , Lung Neoplasms/genetics , Lung Neoplasms/mortality , Male , Middle Aged , Mutation , Proportional Hazards Models , Protein Kinase Inhibitors/adverse effects
2.
RNA Biol ; 20(1): 681-692, 2023 01.
Article in English | MEDLINE | ID: mdl-37676049

ABSTRACT

Lamotrigine (Ltg), an anticonvulsant drug, targets initiation factor 2 (IF2), compromises ribosome biogenesis and causes toxicity to Escherichia coli. However, our understanding of Ltg toxicity in E. coli remains unclear. While our in vitro assays reveal no effects of Ltg on the ribosome-dependent GTPase activity of IF2 or its role in initiation as measured by dipeptide formation in a fast kinetics assay, the in vivo experiments show that Ltg causes accumulation of the 17S precursor of 16S rRNA and leads to a decrease in polysome levels in E. coli. IF2 overexpression in E. coli increases Ltg toxicity. However, the overexpression of initiator tRNA (i-tRNA) protects it from the Ltg toxicity. The depletion of i-tRNA or overexpression of its 3GC mutant (lacking the characteristic 3GC base pairs in anticodon stem) enhances Ltg toxicity, and this enhancement in toxicity is synthetic with IF2 overexpression. The Ltg treatment itself causes a detectable increase in IF2 levels in E. coli and allows initiation with an elongator tRNA, suggesting compromise in the fidelity/specificity of IF2 function. Also, Ltg causes increased accumulation of ribosome-binding factor A (RbfA) on 30S ribosomal subunit. Based on our genetic and biochemical investigations, we show that Ltg compromises the function of i-tRNA/IF2 complex in ribosome maturation.


Subject(s)
Anticonvulsants , Escherichia coli Proteins , Lamotrigine/pharmacology , Escherichia coli/genetics , Prokaryotic Initiation Factor-2 , RNA, Transfer, Met/genetics , RNA, Ribosomal, 16S/genetics , Ribosomes , Ribosomal Proteins , Escherichia coli Proteins/genetics
3.
Nucleic Acids Res ; 47(4): 1908-1919, 2019 02 28.
Article in English | MEDLINE | ID: mdl-30608556

ABSTRACT

Initiator tRNAs (i-tRNAs) possess highly conserved three consecutive GC base pairs (GC/GC/GC, 3GC pairs) in their anticodon stems. Additionally, in bacteria and eukaryotic organelles, the amino acid attached to i-tRNA is formylated by Fmt to facilitate its targeting to 30S ribosomes. Mutations in GC/GC/GC to UA/CG/AU in i-tRNACUA/3GC do not affect its formylation. However, the i-tRNACUA/3GC is non-functional in initiation. Here, we characterised an Escherichia coli strain possessing an amber mutation in its fmt gene (fmtam274), which affords initiation with i-tRNACUA/3GC. Replacement of fmt with fmtam274 in the parent strain results in production of truncated Fmt, accumulation of unformylated i-tRNA, and a slow growth phenotype. Introduction of i-tRNACUA/3GC into the fmtam274 strain restores accumulation of formylated i-tRNAs and rescues the growth defect of the strain. We show that i-tRNACUA/3GC causes a low level suppression of am274 in fmtam274. Low levels of cellular Fmt lead to compromised efficiency of formylation of i-tRNAs, which in turn results in distribution of the charged i-tRNAs between IF2 and EF-Tu allowing the plasmid borne i-tRNACUA/3GC to function at both the initiation and elongation steps. We show that a speedy formylation of i-tRNA population is crucial for its preferential binding (and preventing other tRNAs) into the P-site.


Subject(s)
Anticodon/genetics , Nucleic Acid Conformation , RNA, Transfer, Met/chemistry , Ribosomes/chemistry , Anticodon/chemistry , Escherichia coli/chemistry , Escherichia coli/genetics , Plasmids/genetics , RNA, Transfer, Met/genetics , Ribosome Subunits, Small, Bacterial/chemistry , Ribosome Subunits, Small, Bacterial/genetics , Ribosomes/genetics
4.
Nucleic Acids Res ; 47(17): 9115-9131, 2019 09 26.
Article in English | MEDLINE | ID: mdl-31372634

ABSTRACT

Global protein synthesis is emerging as an important player in the context of aging and age-related diseases. However, the intricate molecular networks that regulate protein synthesis are poorly understood. Here, we report that SIRT6, a nuclear-localized histone deacetylase represses global protein synthesis by transcriptionally regulating mTOR signalling via the transcription factor Sp1, independent of its deacetylase activity. Our results suggest that SIRT6 deficiency increases protein synthesis in mice. Further, multiple lines of in vitro evidence suggest that SIRT6 negatively regulates protein synthesis in a cell-autonomous fashion and independent of its catalytic activity. Mechanistically, SIRT6 binds to the zinc finger DNA binding domain of Sp1 and represses its activity. SIRT6 deficiency increased the occupancy of Sp1 at key mTOR signalling gene promoters resulting in enhanced expression of these genes and activation of the mTOR signalling pathway. Interestingly, inhibition of either mTOR or Sp1 abrogated the increased protein synthesis observed under SIRT6 deficient conditions. Moreover, pharmacological inhibition of mTOR restored cardiac function in muscle-specific SIRT6 knockout mice, which spontaneously develop cardiac hypertrophy. Overall, these findings have unravelled a new layer of regulation of global protein synthesis by SIRT6, which can be potentially targeted to combat aging-associated diseases like cardiac hypertrophy.


Subject(s)
Histone Deacetylases/metabolism , Protein Biosynthesis , Sirtuins/metabolism , Sp1 Transcription Factor/metabolism , TOR Serine-Threonine Kinases/metabolism , Transcription, Genetic , Animals , Cardiomegaly/genetics , Gene Expression Regulation , HEK293 Cells , HeLa Cells , Histone Deacetylases/genetics , Humans , Mice , Mice, Knockout , Promoter Regions, Genetic , Signal Transduction , Sirtuins/genetics , Sp1 Transcription Factor/chemistry , Zinc Fingers
5.
J Immunol ; 201(12): 3617-3629, 2018 12 15.
Article in English | MEDLINE | ID: mdl-30429285

ABSTRACT

Tissue repair is a complex process that necessitates an interplay of cellular processes, now known to be dictated by epigenetics. Intriguingly, macrophages are testimony to a large repertoire of evolving functions in this process. We identified a role for BMP signaling in regulating macrophage responses to Candida albicans infection during wound repair in a murine model. In this study, the RNA binding protein, AU-rich element-binding factor 1, was posttranslationally destabilized to bring about ubiquitin ligase, NEDD4-directed activation of BMP signaling. Concomitantly, PI3K/PKCδ mobilized the rapid phosphorylation of BMP-responsive Smad1/5/8. Activated BMP pathway orchestrated the elevated recruitment of EZH2 at promoters of genes assisting timely wound closure. In vivo, the repressive H3K27 trimethylation was observed to persist, accompanied by a robust upregulation of BMP pathway upon infection with C. albicans, culminating in delayed wound healing. Altogether, we uncovered the signaling networks coordinated by fungal colonies that are now increasingly associated with the infected wound microbiome, resulting in altered wound fate.


Subject(s)
Bone Morphogenetic Proteins/metabolism , Candida albicans/physiology , Candidiasis/immunology , Enhancer of Zeste Homolog 2 Protein/metabolism , Heterogeneous-Nuclear Ribonucleoprotein D/metabolism , Macrophages/physiology , Wound Healing , Animals , Candidiasis/metabolism , Disease Models, Animal , Heterogeneous Nuclear Ribonucleoprotein D0 , Humans , Mice , Mice, Inbred BALB C , Protein Processing, Post-Translational , RAW 264.7 Cells , Signal Transduction
6.
Nucleic Acids Res ; 45(4): 2040-2050, 2017 02 28.
Article in English | MEDLINE | ID: mdl-28204695

ABSTRACT

Eubacterial translation initiation involves assembly of tRNAfMet, mRNA, initiation factors (IFs) and 30S ribosome in a 30S pre-initiation complex (30S pre-IC), which rearranges and joins 50S ribosome to form 70S IC. Upon releasing IFs, 70S IC becomes elongation-competent 70S. The direct recruitment of initiator tRNA (tRNAfMet) into the ribosomal P-site, crucial in accurate initiation of translation, is attributed to two conserved features of tRNAfMet: (i) formylation of amino acid attached to it and, (ii) the presence of three consecutive G-C base pairs (3GC base pairs) in the anticodon stem. However, the precise roles of these two conserved features of tRNAfMet during the various steps of initiation remain unclear. Using natural and engineered tRNAs, we show that the 3GC pairs license tRNAfMet transitions from 30S to 70S IC and then to elongation-competent 70S by release of IF3. Of the 3GC pairs, the middle GC pair (G30-C40), or merely G30 (in a specific context) suffices in this role and is essential for the sustenance of Escherichia coli. Furthermore, rescue of formylase deficient E. coli by overproduced tRNAfMet reveals that the feature of formylation licenses initial targeting of tRNAfMet to 30S ribosome


Subject(s)
Peptide Chain Initiation, Translational , RNA, Transfer, Met/chemistry , Anticodon , Base Pairing , Escherichia coli/genetics , Escherichia coli/growth & development , Mutation , Prokaryotic Initiation Factor-3/metabolism , RNA, Transfer, Met/metabolism , Ribosome Subunits, Small, Bacterial/metabolism , Ribosomes/metabolism
7.
Lancet Oncol ; 19(6): 799-811, 2018 06.
Article in English | MEDLINE | ID: mdl-29753703

ABSTRACT

BACKGROUND: Malignant pleural mesothelioma is an aggressive cancer with highly vascularised tumours. It has poor prognosis and few treatment options after failure of first-line chemotherapy. NGR-hTNF is a vascular-targeting drug that increases penetration of intratumoral chemotherapy and T-cell infiltration by modifying the tumour microenvironment. In this trial, we aimed to investigate the efficacy and safety of NGR-hTNF in patients with malignant pleural mesothelioma who had progressed during or after a first-line treatment. METHODS: NGR015 was a randomised, double-blind, placebo-controlled phase 3 trial done in 41 centres in 12 countries. Eligible participants had malignant pleural mesothelioma of any histological subtype (epithelial, sarcomatoid, or mixed), were aged 18 years or older, and had an Eastern Cooperative Oncology Group performance status of 0-2 and radiologically documented progressive disease after one pemetrexed-based chemotherapy regimen. Participants were randomly assigned to receive weekly NGR-hTNF 0·8 µg/m2 intravenously plus best investigator choice (n=200), or placebo plus best investigator choice (n=200). Best investigator choice was decided before random assignment and could be single-agent gemcitabine (1000-1250 mg/m2 intravenously), vinorelbine (25 mg/m2 intravenously or 60 mg/m2 orally), doxorubicin (60-75 mg/m2 intravenously), or best supportive care only. Patients were randomised (1:1) with a block size of four after stratification for performance status and best investigator choice. The primary study endpoint was overall survival in the intention-to-treat population. The trial is closed to new participants and is registered with ClinicalTrials.gov (NCT01098266). FINDINGS: Between April 12, 2010 and Jan 21, 2013, we enrolled 400 eligible participants. 381 (95%) of 400 patients were selected to receive chemotherapy before all participants were randomly assigned to receive NGF-hTNF plus best investigator choice (n=200) or placebo plus best investigator choice (n=200). At the cutoff date (April 29, 2014), the median follow-up was 18·7 months (IQR 15·1-24·4), and overall survival did not differ between the two treatment groups (median 8·5 months [95% CI 7·2-9·9] in the NGR-hTNF group vs 8·0 months [6·6-8·9] in the placebo group; hazard ratio 0·94, 95% CI 0·75-1·18; p=0·58). Grade 3 or worse study-emergent adverse events occurred in 136 (70%) of patients receiving NGR-hTNF versus 118 (61%) of patients receiving placebo, with the most common being neutropenia (35 [18%] of 193 patients vs 36 [19%] of 193 patients), pain (11 [6%] vs 16 [8%]), dyspnoea (nine [5%] vs seven [4%]), and chills (nine [5%] vs none). 50 (26%) patients in the NGR-hTNF group had a serious adverse event, compared with 47 (24%) in the placebo group. Treatment-related serious adverse events occurred in 17 (9%) patients in the NGR-hTNF group and 20 patients (10%) in the placebo group. There were 12 deaths in the NGR-hTNF group and 13 deaths in the placebo group, but none were treatment related. INTERPRETATION: The study did not meet its primary endpoint. The hypothesis-generating findings from the subgroup analyses deserve a confirmatory randomised trial because patients who rapidly progress after first-line treatment have a poor prognosis. FUNDING: MolMed.


Subject(s)
Angiogenesis Inhibitors/administration & dosage , Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Lung Neoplasms/drug therapy , Mesothelioma/drug therapy , Pleural Neoplasms/drug therapy , Recombinant Fusion Proteins/administration & dosage , Tumor Necrosis Factor-alpha/administration & dosage , Administration, Intravenous , Administration, Oral , Adult , Aged , Aged, 80 and over , Angiogenesis Inhibitors/adverse effects , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Clinical Decision-Making , Disease Progression , Double-Blind Method , Drug Administration Schedule , Female , Humans , Lung Neoplasms/mortality , Lung Neoplasms/pathology , Male , Mesothelioma/mortality , Mesothelioma/pathology , Mesothelioma, Malignant , Middle Aged , Patient Selection , Pleural Neoplasms/mortality , Pleural Neoplasms/pathology , Recombinant Fusion Proteins/adverse effects , Retreatment , Time Factors , Treatment Outcome , Tumor Necrosis Factor-alpha/adverse effects
8.
Microbiology (Reading) ; 164(7): 982-991, 2018 07.
Article in English | MEDLINE | ID: mdl-29799386

ABSTRACT

Dihydrofolate reductase (DHFR) and 5-aminoimidazole-4-carboxamide ribonucleotide (AICAR) transformylase/IMP cyclohydrolase (PurH) play key roles in maintaining folate pools in cells, and are targets of antimicrobial and anticancer drugs. While the activities of bacterial DHFR and PurH on their classical substrates (DHF and 10-CHO-THF, respectively) are known, their activities and kinetic properties of utilisation of 10-CHO-DHF are unknown. We have determined the kinetic properties (kcat/Km) of conversion of 10-CHO-DHF to 10-CHO-THF by DHFR, and to DHF by PurH. We show that DHFR utilises 10-CHO-DHF about one third as efficiently as it utilises DHF. The 10-CHO-DHF is also utilised (as a formyl group donor) by PurH albeit slightly less efficiently than 10-CHO-THF. The utilisation of 10-CHO-DHF by DHFR is ~50 fold more efficient than its utilisation by PurH. A folate deficient Escherichia coli (∆pabA) grows well when supplemented with adenine, glycine, thymine and methionine, the metabolites that arise from the one-carbon metabolic pathway. Notably, when the ∆pabA strain harboured a folate transporter, it grew in the presence of 10-CHO-DHF alone, suggesting that it (10-CHO-DHF) can enter one-carbon metabolic pathway to provide the required metabolites. Thus, our studies reveal that both DHFR and PurH could utilise 10-CHO-DHF for folate homeostasis in E. coli.


Subject(s)
Escherichia coli/metabolism , Folic Acid/analogs & derivatives , Nucleotide Deaminases/metabolism , Phosphoribosylaminoimidazolecarboxamide Formyltransferase/metabolism , Tetrahydrofolate Dehydrogenase/metabolism , 4-Aminobenzoic Acid , Cloning, Molecular , Escherichia coli/genetics , Escherichia coli/growth & development , Folic Acid/metabolism , Folic Acid Deficiency/genetics , Homeostasis , Kinetics , Metabolic Networks and Pathways , Nucleotide Deaminases/genetics , Phosphoribosylaminoimidazolecarboxamide Formyltransferase/genetics , Tetrahydrofolate Dehydrogenase/genetics
9.
RNA Biol ; 15(1): 70-80, 2018 01 02.
Article in English | MEDLINE | ID: mdl-28901843

ABSTRACT

Initiator tRNAs (i-tRNAs) are characterized by the presence of three consecutive GC base pairs (GC/GC/GC) in their anticodon stems in all domains of life. However, many mycoplasmas possess unconventional i-tRNAs wherein the highly conserved sequence of GC/GC/GC is represented by AU/GC/GC, GC/GC/GU or AU/GC/GU. These mycoplasmas also tend to preferentially utilize non-AUG initiation codons. To investigate if initiation with the unconventional i-tRNAs and non-AUG codons in mycoplasmas correlated with the changes in the other components of the translation machinery, we carried out multiple sequence alignments of genes encoding initiation factors (IF), 16S rRNAs, and the ribosomal proteins such as uS9, uS12 and uS13. In addition, the occurrence of Shine-Dalgarno sequences in mRNAs was analyzed. We observed that in the mycoplasmas harboring AU/GC/GU i-tRNAs, a highly conserved position of R131 in IF3, is represented by P, F or Y and, the conserved C-terminal tail (SKR) of uS9 is represented by the TKR sequence. Using the Escherichia coli model, we show that the change of R131 in IF3 optimizes initiation with the AU/GC/GU i-tRNAs. Also, the SKR to TKR change in uS9 was compatible with the R131P variation in IF3 for initiation with the AU/GC/GU i-tRNA variant. Interestingly, the mycoplasmas harboring AU/GC/GU i-tRNAs are also human pathogens. We propose that these mycoplasmas might have evolved a relaxed translational apparatus to adapt to the environment they encounter in the host.


Subject(s)
Evolution, Molecular , Mycoplasma/genetics , Protein Biosynthesis , RNA, Transfer/genetics , Anticodon/genetics , Codon, Initiator/genetics , Escherichia coli/genetics , Humans , Mycoplasma/pathogenicity , Nucleic Acid Conformation , RNA, Ribosomal, 16S/genetics , RNA, Transfer, Met/genetics , Ribosomal Proteins/genetics
10.
Proc Natl Acad Sci U S A ; 111(40): E4224-33, 2014 Oct 07.
Article in English | MEDLINE | ID: mdl-25246575

ABSTRACT

Initiator tRNAs are special in their direct binding to the ribosomal P-site due to the hallmark occurrence of the three consecutive G-C base pairs (3GC pairs) in their anticodon stems. How the 3GC pairs function in this role, has remained unsolved. We show that mutations in either the mRNA or 16S rRNA leading to extended interaction between the Shine-Dalgarno (SD) and anti-SD sequences compensate for the vital need of the 3GC pairs in tRNA(fMet) for its function in Escherichia coli. In vivo, the 3GC mutant tRNA(fMet) occurred less abundantly in 70S ribosomes but normally on 30S subunits. However, the extended SD:anti-SD interaction increased its occurrence in 70S ribosomes. We propose that the 3GC pairs play a critical role in tRNA(fMet) retention in ribosome during the conformational changes that mark the transition of 30S preinitiation complex into elongation competent 70S complex. Furthermore, treating cells with kasugamycin, decreasing ribosome recycling factor (RRF) activity or increasing initiation factor 2 (IF2) levels enhanced initiation with the 3GC mutant tRNA(fMet), suggesting that the 70S mode of initiation is less dependent on the 3GC pairs in tRNA(fMet).


Subject(s)
RNA, Messenger/genetics , RNA, Transfer, Met/genetics , Ribosomes/metabolism , Aminoglycosides/pharmacology , Anticodon/genetics , Base Sequence , Binding Sites/genetics , Blotting, Northern , Escherichia coli/drug effects , Escherichia coli/genetics , Escherichia coli/metabolism , Mutation , Peptide Chain Initiation, Translational/genetics , Prokaryotic Initiation Factor-2/metabolism , RNA, Messenger/metabolism , RNA, Ribosomal, 16S/metabolism , RNA, Transfer, Met/metabolism , Ribosomal Proteins/metabolism
11.
JCO Glob Oncol ; 10: e2300330, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38484196

ABSTRACT

PURPOSE: Accurate understanding of the genomic and transcriptomic data provided by next-generation sequencing (NGS) is essential for the effective utilization of precision oncology. Molecular tumor boards (MTBs) aim to translate the complex data in NGS reports into effective clinical interventions. Often, MTB treatment recommendations differ from those in the NGS reports. In this study, we analyze the discordance between these recommendations and the rationales behind the discordances, in a non-high-income setting, with international input to evaluate the necessity of MTB in clinical practice. METHODS: We collated data from MTB that were virtually hosted in Chennai, India. We included patients with malignancies who had NGS reports on solid tissue or liquid biopsies, and excluded those with incomplete data. MTB forms and NGS reports of each clinical case were analyzed and evaluated for recommendation concordance. Concordance was defined as an agreement between the first recommendation in the MTB forms and the therapeutic recommendations suggested in the NGS report. Discordance was the absence of the said agreement. The rationales for discordance were identified and documented. RESULTS: Seventy MTB reports were analyzed with 49 cases meeting the inclusion criteria. The recommendation discordance was 49% (24 of 49). Discordant recommendations were mainly due to low level of evidence for the drug (75% of cases). CONCLUSION: The discordance between MTB and NGS vendor recommendations highlights the clinical utility of MTB. The educational experiences provided by this initiative are an example of how virtual academic collaborations can enhance patient care and provider education across geographic borders.


Subject(s)
Neoplasms , Humans , Neoplasms/diagnosis , Neoplasms/genetics , Neoplasms/therapy , Precision Medicine , India , Medical Oncology , High-Throughput Nucleotide Sequencing
12.
Lancet Respir Med ; 12(6): 457-466, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38740044

ABSTRACT

BACKGROUND: Extended pleurectomy decortication for complete macroscopic resection for pleural mesothelioma has never been evaluated in a randomised trial. The aim of this study was to compare outcomes after extended pleurectomy decortication plus chemotherapy versus chemotherapy alone. METHODS: MARS 2 was a phase 3, national, multicentre, open-label, parallel two-group, pragmatic, superiority randomised controlled trial conducted in the UK. The trial took place across 26 hospitals (21 recruiting only, one surgical only, and four recruiting and surgical). Following two cycles of chemotherapy, eligible participants with pleural mesothelioma were randomly assigned (1:1) to surgery and chemotherapy or chemotherapy alone using a secure web-based system. Individuals aged 16 years or older with resectable pleural mesothelioma and adequate organ and lung function were eligible for inclusion. Participants in the chemotherapy only group received two to four further cycles of chemotherapy, and participants in the surgery and chemotherapy group received pleurectomy decortication or extended pleurectomy decortication, followed by two to four further cycles of chemotherapy. It was not possible to mask allocation because the intervention was a major surgical procedure. The primary outcome was overall survival, defined as time from randomisation to death from any cause. Analyses were done on the intention-to-treat population for all outcomes, unless specified. This study is registered with ClinicalTrials.gov, NCT02040272, and is closed to new participants. FINDINGS: Between June 19, 2015, and Jan 21, 2021, of 1030 assessed for eligibility, 335 participants were randomly assigned (169 to surgery and chemotherapy, and 166 to chemotherapy alone). 291 (87%) participants were men and 44 (13%) women, and 288 (86%) were diagnosed with epithelioid mesothelioma. At a median follow-up of 22·4 months (IQR 11·3-30·8), median survival was shorter in the surgery and chemotherapy group (19·3 months [IQR 10·0-33·7]) than in the chemotherapy alone group (24·8 months [IQR 12·6-37·4]), and the difference in restricted mean survival time at 2 years was -1·9 months (95% CI -3·4 to -0·3, p=0·019). There were 318 serious adverse events (grade ≥3) in the surgery group and 169 in the chemotherapy group (incidence rate ratio 3·6 [95% CI 2·3 to 5·5], p<0·0001), with increased incidence of cardiac (30 vs 12; 3·01 [1·13 to 8·02]) and respiratory (84 vs 34; 2·62 [1·58 to 4·33]) disorders, infection (124 vs 53; 2·13 [1·36 to 3·33]), and additional surgical or medical procedures (15 vs eight; 2·41 [1·04 to 5·57]) in the surgery group. INTERPRETATION: Extended pleurectomy decortication was associated with worse survival to 2 years, and more serious adverse events for individuals with resectable pleural mesothelioma, compared with chemotherapy alone. FUNDING: National Institute for Health and Care Research (NIHR) Health Technology Assessment programme (15/188/31), Cancer Research UK Feasibility Studies Project Grant (A15895).


Subject(s)
Mesothelioma , Pleural Neoplasms , Humans , Female , Male , Pleural Neoplasms/surgery , Pleural Neoplasms/drug therapy , Pleural Neoplasms/mortality , Middle Aged , Aged , Mesothelioma/surgery , Mesothelioma/drug therapy , Mesothelioma/mortality , Treatment Outcome , United Kingdom , Pleura/surgery , Mesothelioma, Malignant/surgery , Mesothelioma, Malignant/drug therapy , Combined Modality Therapy/methods , Adult , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Lung Neoplasms/surgery , Lung Neoplasms/drug therapy , Lung Neoplasms/mortality , Lung Neoplasms/pathology
13.
BMC Cancer ; 13: 207, 2013 Apr 26.
Article in English | MEDLINE | ID: mdl-23617826

ABSTRACT

BACKGROUND: Single arm phase 1 and 2 studies on Crizotinib in ALK-positive patients so far have shown rapid and durable responses. Spontaneous pneumothoraces as a result of response to anti-cancer therapy are rare in oncology but have been documented in a number of tumour types including lung cancer. This includes cytotoxic chemotherapy as well as molecular targeted agents such as gefitinib and Bevacizumab. These often require chest drain insertion or surgical intervention with associated morbidity and mortality. They have also been associated with response to treatment. This is the first report we are aware of documenting pneumothorax as response to crizotinib therapy. CASE PRESENTATION: A 48-year-old Caucasian male presented with a Stage IV, TTF1 positive, EGFR wild-type adenocarcinoma of the lung. He received first line chemotherapy with three cycles of cisplatin-pemetrexed chemotherapy with a differential response, and then second-line erlotinib for two months before further radiological evidence of disease progression. Further analysis of his diagnostic specimen identified an ALK rearrangement by fluorescence in situ hybridization (FISH). He was commenced on crizotinib therapy 250 mg orally twice daily. At his 4-week assessment he had a chest radiograph that identified a large left-sided pneumothorax with disease response evident on the right. Chest CT confirmed a 50% left-sided pneumothorax on a background of overall disease response. A chest tube was inserted with complete resolution of the pneumothorax that did not recur following its removal. CONCLUSION: Our case demonstrates this potential complication of crizotinib therapy and we therefore recommend that pneumothorax be considered in patients on crizotinib presenting with high lung metastatic burden and with worsening dyspnoea.


Subject(s)
Adenocarcinoma/drug therapy , Carcinoma, Non-Small-Cell Lung/drug therapy , Gene Rearrangement , Lung Neoplasms/drug therapy , Pneumothorax/chemically induced , Protein Kinase Inhibitors/adverse effects , Pyrazoles/adverse effects , Pyridines/adverse effects , Receptor Protein-Tyrosine Kinases/genetics , Adenocarcinoma/complications , Adenocarcinoma/genetics , Adenocarcinoma/pathology , Anaplastic Lymphoma Kinase , Carcinoma, Non-Small-Cell Lung/complications , Carcinoma, Non-Small-Cell Lung/genetics , Carcinoma, Non-Small-Cell Lung/pathology , Crizotinib , Humans , In Situ Hybridization, Fluorescence , Lung Neoplasms/complications , Lung Neoplasms/genetics , Lung Neoplasms/pathology , Male , Middle Aged , Pneumothorax/diagnosis , Prognosis
14.
Cell Death Dis ; 14(7): 467, 2023 07 26.
Article in English | MEDLINE | ID: mdl-37495584

ABSTRACT

Impairment of protein translation can cause stalling and collision of ribosomes and is a signal for the activation of ribosomal surveillance and rescue pathways. Despite clear evidence that ribosome collision occurs stochastically at a cellular and organismal level, physiologically relevant sources of such aberrations are poorly understood. Here we show that a burst of the cellular signaling molecule nitric oxide (NO) reduces translational activity and causes ribosome collision in human cell lines. This is accompanied by activation of the ribotoxic stress response, resulting in ZAKα-mediated activation of p38 and JNK kinases. In addition, NO production is associated with ZNF598-mediated ubiquitination of the ribosomal protein RPS10 and GCN2-mediated activation of the integrated stress response, which are well-described responses to the collision of ribosomes. In sum, our work implicates a novel role of NO as an inducer of ribosome collision and activation of ribosomal surveillance mechanisms in human cells.


Subject(s)
Nitric Oxide , Ribosomes , Humans , Nitric Oxide/metabolism , Ribosomes/metabolism , Protein Biosynthesis , Ribosomal Proteins/genetics , Ribosomal Proteins/metabolism , Ubiquitination , Carrier Proteins/metabolism
15.
Nat Commun ; 14(1): 1070, 2023 02 27.
Article in English | MEDLINE | ID: mdl-36849494

ABSTRACT

Osimertinib, an epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI), potently and selectively inhibits EGFR-TKI-sensitizing and EGFR T790M resistance mutations. In the Phase III FLAURA study (NCT02296125), first-line osimertinib improved outcomes vs comparator EGFR-TKIs in EGFRm advanced non-small cell lung cancer. This analysis identifies acquired resistance mechanisms to first-line osimertinib. Next-generation sequencing assesses circulating-tumor DNA from paired plasma samples (baseline and disease progression/treatment discontinuation) in patients with baseline EGFRm. No EGFR T790M-mediated acquired resistance are observed; most frequent resistance mechanisms are MET amplification (n = 17; 16%) and EGFR C797S mutations (n = 7; 6%). Future research investigating non-genetic acquired resistance mechanisms is warranted.


Subject(s)
Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , Humans , Carcinoma, Non-Small-Cell Lung/drug therapy , Carcinoma, Non-Small-Cell Lung/genetics , ErbB Receptors/genetics , Lung Neoplasms/drug therapy , Lung Neoplasms/genetics , Mutation , Protein Kinase Inhibitors/pharmacology , Protein Kinase Inhibitors/therapeutic use
16.
J Clin Oncol ; 41(16): 2869-2876, 2023 Jun 01.
Article in English | MEDLINE | ID: mdl-37235976

ABSTRACT

PURPOSE: The LUX-Lung 3 study investigated the efficacy of chemotherapy compared with afatinib, a selective, orally bioavailable ErbB family blocker that irreversibly blocks signaling from epidermal growth factor receptor (EGFR/ErbB1), human epidermal growth factor receptor 2 (HER2/ErbB2), and ErbB4 and has wide-spectrum preclinical activity against EGFR mutations. A phase II study of afatinib in EGFR mutation-positive lung adenocarcinoma demonstrated high response rates and progression-free survival (PFS). PATIENTS AND METHODS: In this phase III study, eligible patients with stage IIIB/IV lung adenocarcinoma were screened for EGFR mutations. Mutation-positive patients were stratified by mutation type (exon 19 deletion, L858R, or other) and race (Asian or non-Asian) before two-to-one random assignment to 40 mg afatinib per day or up to six cycles of cisplatin plus pemetrexed chemotherapy at standard doses every 21 days. The primary end point was PFS by independent review. Secondary end points included tumor response, overall survival, adverse events, and patient-reported outcomes (PROs). RESULTS: A total of 1,269 patients were screened, and 345 were randomly assigned to treatment. Median PFS was 11.1 months for afatinib and 6.9 months for chemotherapy (hazard ratio [HR], 0.58; 95% CI, 0.43 to 0.78; P = .001). Median PFS among those with exon 19 deletions and L858R EGFR mutations (n = 308) was 13.6 months for afatinib and 6.9 months for chemotherapy (HR, 0.47; 95% CI, 0.34 to 0.65; P = .001). The most common treatment-related adverse events were diarrhea, rash/acne, and stomatitis for afatinib and nausea, fatigue, and decreased appetite for chemotherapy. PROs favored afatinib, with better control of cough, dyspnea, and pain. CONCLUSION: Afatinib is associated with prolongation of PFS when compared with standard doublet chemotherapy in patients with advanced lung adenocarcinoma and EGFR mutations.

17.
J Immunother Cancer ; 11(10)2023 10.
Article in English | MEDLINE | ID: mdl-37880184

ABSTRACT

BACKGROUND: Few tissue biomarkers exist to date that could enrich patient with cancer populations to benefit from immune checkpoint blockade by programmed cell death protein 1/ligand-1 (PD-/L-1) inhibitors. PD-L1 expression has value in this context in some tumor types but is an imperfect predictor of clinical benefit. In malignant pleural mesothelioma, PD-L1 expression is not predictive of the benefit from PD-1 blockade. We aimed to identify novel markers in malignant pleural mesothelioma to select patients better. METHODS: We performed a multiplex-immune histochemistry analysis of tumor samples from the phase III PROMISE-meso study, which randomized 144 pretreated patients to receive either pembrolizumab or standard second-line chemotherapy. Our panel focused on CD8+T cell, CD68+macrophages, and the expression of PD-1 and PD-L1 on these and cancer cells. We analyzed single and double positive cells within cancer tissues (infiltrating immune cells) and in the stroma. In addition, we performed cell neighborhood analysis. The cell counts were compared with clinical outcomes, including responses, progression-free and overall survivals. RESULTS: We confirmed the absence of predictive value for PD-L1 in this cohort of patients. Furthermore, total CD8 T cells, CD68+macrophages, or inflammatory subtypes (desert, excluded, inflamed) did not predict outcomes. In contrast, PD-1-expressing CD8+T cells (exhausted T cells) and PD-1-expressing CD68+macrophages were both independent predictors of progression-free survival benefit from pembrolizumab. Patients with tumors simultaneously harboring PD1+T cells and PD-1+macrophages benefited the most from immune therapy. CONCLUSION: We analyzed a large cohort of patients within a phase III study and found that not only PD-1+CD8 T cells but also PD-1+CD68+ macrophages are predictive. This data provides evidence for the first time for the existence of PD-1+macrophages in mesothelioma and their clinical relevance for immune checkpoint blockade.


Subject(s)
Lung Neoplasms , Mesothelioma, Malignant , Mesothelioma , Humans , Mesothelioma, Malignant/drug therapy , Mesothelioma, Malignant/metabolism , B7-H1 Antigen/metabolism , Programmed Cell Death 1 Receptor , Lung Neoplasms/pathology , Immune Checkpoint Inhibitors/therapeutic use , Mesothelioma/drug therapy , Mesothelioma/pathology , CD8-Positive T-Lymphocytes , Macrophages
18.
J Mol Biol ; 434(12): 167588, 2022 06 30.
Article in English | MEDLINE | ID: mdl-35439479

ABSTRACT

The fidelity of initiator tRNA (i-tRNA) selection in the ribosomal P-site is a key step in translation initiation. The highly conserved three consecutive G:C base pairs (3GC pairs) in the i-tRNA anticodon stem play a crucial role in its selective binding in the P-site. Mutations in the 3GC pairs (3GC mutant) render the i-tRNA inactive in initiation. Here, we show that a mutation (E265K) in the unique C-terminal tail domain of RluD, a large ribosomal subunit pseudouridine synthase, results in compromised fidelity of initiation and allows initiation with the 3GC mutant i-tRNA. RluD modifies the uridine residues in H69 to pseudouridines. However, the role of its C-terminal tail domain remained unknown. The E265K mutation does not diminish the pseudouridine synthase activity of RluD, or the growth phenotype of Escherichia coli, or cause any detectable defects in the ribosomal assembly in our assays. However, in our in vivo analyses, we observed that the E265K mutation resulted in increased retention of the ribosome binding factor A (RbfA) on 30S suggesting a new role of RluD in contributing to RbfA release, a function which may be attributed to its (RluD) C-terminal tail domain. The studies also reveal that deficiency of RbfA release from 30S compromises the fidelity of i-tRNA selection in the ribosomal P-site.


Subject(s)
Escherichia coli Proteins , Escherichia coli , Peptide Chain Initiation, Translational , Ribosomal Proteins , Anticodon/genetics , Anticodon/metabolism , Escherichia coli/genetics , Escherichia coli/metabolism , Escherichia coli Proteins/genetics , Escherichia coli Proteins/metabolism , Hydro-Lyases/chemistry , Mutation , Pseudouridine/biosynthesis , RNA, Transfer, Met/genetics , RNA, Transfer, Met/metabolism , Ribosomal Proteins/genetics , Ribosomal Proteins/metabolism
19.
Lung Cancer ; 171: 26-33, 2022 09.
Article in English | MEDLINE | ID: mdl-35872530

ABSTRACT

OBJECTIVES: Small cell lung cancer (SCLC) responds well to chemoradiotherapy but frequently relapses. Here, we evaluate activity and safety of the poly (adenosine diphosphate (ADP)-ribose) polymerase (PARP) inhibitor olaparib as maintenance treatment for patients with chemoresponsive SCLC. MATERIALS AND METHODS: Eligible patients had complete or partial response to first line chemotherapy or chemoradiotherapy for SCLC. Patients were randomised 2:2:1:1 to olaparib 300 mg twice a day (BD), olaparib 200 mg three times a day (TDS), placebo BD or placebo TDS. The primary outcome was progression-free survival time (PFS). The trial design had 80% power to detect a 3-month difference in median PFS based on a one-sided 5% significance level. Secondary outcome measures included overall survival time (OS), adverse events and quality of life. ISRCTN 73164486, EudraCT 2010-021165-76. RESULTS: 220 patients were randomised: 74 placebo, 73 olaparib BD, 73 olaparib TDS. Median PFS (90% confidence interval (CI)) was 2·5 (1·8, 3·7), 3·7 (3·1, 4·6) and 3·6 (2·8, 4·7) months in the placebo, olaparib BD and TDS arms, respectively. There was no significant difference in PFS between olaparib and placebo for either BD (Hazard Ratio (HR) (90%CI) 0·76 (0·57, 1·02), P = 0·125 or TDS 0·86, (0·64, 1·15), P = 0·402. Common adverse events on olaparib were fatigue, nausea, anaemia, vomiting and anorexia. Of 214 patients who discontinued treatment before 24 months, toxicity was the reason cited for 66 (18 placebo, 24 olaparib BD, 24 olaparib TDS). CONCLUSION: This trial does not provide sufficient evidence that either the BD or TDS regimen for maintenance olaparib monotherapy improves PFS or OS in an unselected SCLC population to warrant further research. Toxicity for olaparib was similar to other studies.


Subject(s)
Antineoplastic Agents , Lung Neoplasms , Ovarian Neoplasms , Small Cell Lung Carcinoma , Antineoplastic Agents/adverse effects , Double-Blind Method , Female , Humans , Lung Neoplasms/chemically induced , Lung Neoplasms/drug therapy , Neoplasm Recurrence, Local/drug therapy , Ovarian Neoplasms/chemically induced , Ovarian Neoplasms/drug therapy , Phthalazines , Piperazines , Quality of Life , Small Cell Lung Carcinoma/drug therapy
20.
Lung Cancer ; 169: 77-83, 2022 07.
Article in English | MEDLINE | ID: mdl-35660972

ABSTRACT

INTRODUCTION: Clinical and laboratory parameters associated with response for patients with advanced pre-treated malignant pleural mesothelioma (MPM) are lacking. We aimed to identify prognostic and predictive markers among patients with relapsed MPM who were randomised into the ETOP 9-15 PROMISE-meso phase III trial, evaluating pembrolizumab and chemotherapy. METHODS: Baseline clinical and laboratory parameters were investigated for prognostic or predictive value on progression-free survival (PFS) and overall survival (OS) in a retrospective analysis, based on the full cohort of 144 MPM patients. These consisted of immune-inflammatory indexes (neutrophil-lymphocyte ratio [NLR], systemic immune-inflammatory index [SII], lactate dehydrogenase [LDH]) along with other already known prognostic baseline characteristics and laboratory values. Cut-offs were chosen independently of outcome. Based on Cox multivariable analysis for PFS in the whole cohort, a risk factor model was built to illustrate the prognostic stratification of patients by the combination of the derived independent prognostic factors, taking into account the EORTC score, a validated prognostic score in MPM. All models were stratified by histology and adjusted by treatment. RESULTS: In the stratified multivariable analysis in the whole cohort, high SII (hazard ratio (HR) 2.06; 95%CI 1.39-3.05) and low haemoglobin (HR 1.62; 95%CI 1.06-2.50) were associated with worse PFS. Based on these two prognostic factors, a mesothelioma risk score (MRS) was constructed with three PFS risk prognosis categories: favourable, intermediate and poor with 0, 1 and 2 risk factors, respectively (corresponding percent of cohort: 24%, 34% and 42% and median PFS: 5.8, 4.2 and 2.1 months). The derived MRS stratified the prognosis for PFS and OS, overall and within each of the EORTC groups. No significant predictors of treatment benefit were identified. CONCLUSIONS: The proposed MRS is prognostic of patient outcome and it fine-tunes the prognosis of patients with pre-treated MPM alone or when used with the already established EORTC score.


Subject(s)
Lung Neoplasms , Mesothelioma, Malignant , Mesothelioma , Pleural Neoplasms , Humans , Immunotherapy , Lung Neoplasms/pathology , Mesothelioma/pathology , Pleural Neoplasms/pathology , Prognosis , Retrospective Studies
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