Clinical evaluation of a low-coverage whole-genome test for detecting homologous recombination deficiency in ovarian cancer

BACKGROUND

The PAOLA-1/ENGOT-ov25 trial showed that maintenance olaparib plus bevacizumab increases survival of advanced ovarian cancer patients with homologous recombination deficiency (HRD). However, decentralized solutions to test for HRD in clinical routine are scarce. The goal of this study was to retrospectively validate on tumor samples from the PAOLA-1 trial, the decentralized SeqOne assay, which relies on shallow Whole Genome Sequencing (sWGS) to capture genomic instability and targeted sequencing to determine BRCA status.

METHODS

The study comprised 368 patients from the PAOLA-1 trial. The SeqOne assay was compared to the Myriad MyChoice HRD test (Myriad Genetics), and results were analyzed with respect to Progression-Free Survival (PFS).

RESULTS

We found a 95% concordance between the HRD status of the two tests (95% Confidence Interval (CI); 92%-97%). The Positive Percentage Agreement (PPA) of the sWGS test was 95% (95% CI; 91%-97%) like its Negative Percentage Agreement (NPA) (95% CI; 89%-98%). In patients with HRD-positive tumors treated with olaparib plus bevacizumab, the PFS Hazard Ratio (HR) was 0.38 (95% CI; 0.26-0.54) with SeqOne assay and 0.32 (95% CI; 0.22-0.45) with the Myriad assay. In patients with HRD-negative tumors, HR was 0.99 (95% CI; 0.68-1.42) and 1.05 (95% CI; 0.70-1.57) with SeqOne and Myriad assays. Among patients with BRCA-wildtype tumors, those with HRD-positive tumors, benefited from olaparib plus bevacizumab maintenance, with HR of 0.48 (95% CI: 0.29-0.79) and of 0.38 (95% CI: 0.23 to 0.63) with the SeqOne and Myriad assay.

CONCLUSION

The SeqOne assay offers a clinically validated approach to detect HRD.

Regulatory T-cell dysfunctions are associated with increase in tumor necrosis factor α in autoimmune hemolytic anemia and participate in Th17 polarization

Warm autoimmune hemolytic anemia (wAIHA) is a rare acquired autoimmune disease mediated by antibodies targeting red blood cells. The involvement of CD4 T-helper cells has been scarcely explored, with most findings extrapolated from animal models. Here, we performed quantification of both effector T lymphocytes (Teff) and regulatory T cells (Treg), associated with functional and transcriptomic analyses of Treg in human wAIHA. We observed a shift of Teff toward a Th17 polarization concordant with an increase in serum interleukin-17 concentration that correlates with red blood cell destruction parameters, namely lactate dehydrogenase and bilirubin levels. A decrease in circulating Treg, notably effector Treg, associated with a functional deficiency, as represented by their decrease capability to inhibit Teff proliferation, were also observed. Treg deficiency was associated with a reduced expression of Foxp3, the master transcription factor known to maintain the Treg phenotype stability and suppressive functions. Transcriptomic profiling of Treg revealed activation of the tumor necrosis facto (TNF)-α pathway, which was linked to increased serum TNF-α concentrations that were twice as high as in controls. Treg transcriptomic profiling also suggested that post-translational mechanisms possibly accounted for Foxp3 downregulation and Treg dysfunctions. Since TNF-α participates in the rupture of immune tolerance during wAIHA, its inhibition could be of interest. To this end, the effects of fostamatinib, a SYK inhibitor, were investigated in vitro, and we showed that besides the inhibition of erythrocyte phagocytosis by monocytes, fostamatinib is also able to dampen TNF-α production, thus appearing as a promising multitargeting therapy in wAIHA (clinicaltrials gov. Identifier: NCT02158195).

Durable response of lung carcinoma patients to EGFR tyrosine kinase inhibitors is determined by germline polymorphisms in some immune-related genes

BACKGROUND

Non-small cell lung cancer is a very poor prognosis disease. Molecular analyses have highlighted several genetic alterations which may be targeted by specific therapies. In clinical practice, progression-free survival on EGFR TKI treatment is between 12 and 14 months. However, some patients progress rapidly in less than 6 months, while others remain free of progression for 16 months or even longer during EGFR TKI treatment.

METHODS

We sequenced tumor exomes from 135 lung cancer patients (79 with EGFR-wildtype (WT), 56 with EGFR-mutant tumors) enrolled in the ALCAPONE trial (genomic analysis of lung cancers by next generation sequencing for personalized treatment).

RESULTS

Some germline polymorphisms were enriched in the EGFR-mutant subset compared to EGFR-WT tumors or to a reference population. However, the most interesting observation was the negative impact of some germline SNPs in immunity-related genes on survival on EGFR TKI treatment. Indeed, the presence of one of three particular SNPs in the HLA-DRB5 gene was associated with a decreased PFS on EGFR TKI. Moreover, some SNPs in the KIR3DL1 and KIR3DL2 genes were linked to a decrease in both progression-free and overall survival of patients with EGFR-mutant tumors.

CONCLUSION

Our data suggest that SNPs in genes expressed by immune cells may influence the response to targeted treatments, such as EGFR TKIs. This indicates that the impact of these cells may not be limited to modulating the response to immunotherapies. Further studies are needed to determine the exact mechanisms underlying this influence and to identify the associated predictive and prognostic markers that would allow to refine treatments and so improve lung cancer patient outcomes.

TRIAL REGISTRATION

NCT02281214: NGS Genome Analysis in Personalization of Lung Cancer Treatment (ALCAPONE).

Exome-Based Genomic Markers Could Improve Prediction of Checkpoint Inhibitor Efficacy Independently of Tumor Type

Immune checkpoint inhibitors (ICIs) have improved the care of patients in multiple cancer types. However, PD-L1 status, high Tumor Mutational Burden (TMB), and mismatch repair deficiency are the only validated biomarkers of efficacy for ICIs. These markers remain imperfect, and new predictive markers represent an unmet medical need. Whole-exome sequencing was carried out on 154 metastatic or locally advanced cancers from different tumor types treated by immunotherapy. Clinical and genomic features were investigated using Cox regression models to explore their capacity to predict progression-free survival (PFS). The cohort was split into training and validation sets to assess validity of observations. Two predictive models were estimated using clinical and exome-derived variables, respectively. Stage at diagnosis, surgery before immunotherapy, number of lines before immunotherapy, pleuroperitoneal, bone or lung metastasis, and immune-related toxicity were selected to generate a clinical score. KRAS mutations, TMB, TCR clonality, and Shannon entropy were retained to generate an exome-derived score. The addition of the exome-derived score improved the prediction of prognosis compared with the clinical score alone. Exome-derived variables could be used to predict responses to ICI independently of tumor type and might be of value in improving patient selection for ICI therapy.

Hematopoietic Prostaglandin D2 Synthase Controls Tfh/Th2 Communication and Limits Tfh Antitumor Effects

T follicular helper (Tfh) cells are a subset of CD4+ T cells essential in immunity and have a role in helping B cells produce antibodies against pathogens. However, their role during cancer progression remains unknown. The mechanism of action of Tfh cells remains elusive because contradictory data have been reported on their protumor or antitumor responses in human and murine tumors. Like Tfh cells, Th2 cells are also involved in humoral immunity and are regularly associated with tumor progression and poor prognosis, mainly through their secretion of IL4. Here, we showed that Tfh cells expressed hematopoietic prostaglandin D2 (PGD2) synthase in a pSTAT1/pSTAT3-dependent manner. Tfh cells produced PGD2, which led to recruitment of Th2 cells via the PGD2 receptor chemoattractant receptor homologous molecule expressed on Th type 2 cells (CRTH2) and increased their effector functions. This cross-talk between Tfh and Th2 cells promoted IL4-dependent tumor growth. Correlation between Th2 cells, Tfh cells, and hematopoietic PGD2 synthase was observed in different human cancers and associated with outcome. This study provides evidence that Tfh/Th2 cross-talk through PGD2 limits the antitumor effects of Tfh cells and, therefore, could serve as a therapeutic target.

A Natural Polyphenol Exerts Antitumor Activity and Circumvents Anti-PD-1 Resistance through Effects on the Gut Microbiota

Several approaches to manipulate the gut microbiome for improving the activity of cancer immune-checkpoint inhibitors (ICI) are currently under evaluation. Here, we show that oral supplementation with the polyphenol-rich berry camu-camu (CC; Myrciaria dubia) in mice shifted gut microbial composition, which translated into antitumor activity and a stronger anti-PD-1 response. We identified castalagin, an ellagitannin, as the active compound in CC. Oral administration of castalagin enriched for bacteria associated with efficient immunotherapeutic responses (Ruminococcaceae and Alistipes) and improved the CD8+/FOXP3+CD4+ ratio within the tumor microenvironment. Moreover, castalagin induced metabolic changes, resulting in an increase in taurine-conjugated bile acids. Oral supplementation of castalagin following fecal microbiota transplantation from ICI-refractory patients into mice supported anti-PD-1 activity. Finally, we found that castalagin binds to Ruminococcus bromii and promoted an anticancer response. Altogether, our results identify castalagin as a polyphenol that acts as a prebiotic to circumvent anti-PD-1 resistance.

SIGNIFICANCE

The polyphenol castalagin isolated from a berry has an antitumor effect through direct interactions with commensal bacteria, thus reprogramming the tumor microenvironment. In addition, in preclinical ICI-resistant models, castalagin reestablishes the efficacy of anti-PD-1. Together, these results provide a strong biological rationale to test castalagin as part of a clinical trial. This article is highlighted in the In This Issue feature, p. 873.

MER4 endogenous retrovirus correlated with better efficacy of anti-PD1/PD-L1 therapy in non-small cell lung cancer

Background

Endogenous retroviruses (ERVs) are highly expressed in various cancer types and are associated with increased innate immune response and better efficacy of antiprogrammed death-1/ligand-1 (anti-PD1/PD-L1)-directed immune checkpoint inhibitors (ICI) in preclinical models. However, their role in human non-small cell lung cancer (NSCLC) remains unknown.

Methods

We conducted a retrospective study of patients receiving ICI for advanced NSCLC in two independent cohorts. ERV expression was determined by RNA sequencing. The primary endpoint was progression-free survival (PFS) under ICI. The secondary endpoint was overall survival (OS) from ICI initiation. We studied expression of 6205 ERVs. Multivariate Cox regression model with lasso penalty was estimated on the training set to select ERVs significantly associated with survival. The predictive power of these ERVs was compared with that of previously described transcriptomic signatures.

Results

We studied two independent cohorts of 89 and 70 patients, used as training and validation sets. Clinicopathological characteristics included 75% of patients with non-squamous NSCLC. We selected four ERVs significantly associated with PFS. Only high MER4 ERV was associated with better PFS and OS in both cohorts. From a biological point of view, high MER4 expression is associated with higher infiltration of eosinophils and inflammatory gene signatures, while low MER4 expression is associated with enrichment in metabolism and proliferation signatures. Adding MER4 to previously described transcriptomic signatures of response to ICI improved their predictive power.

Conclusions

MER4 ERV expression is useful to stratify risk and predict PFS and OS in patients treated with ICI for NSCLC. It also improves the predictive power of other known transcriptomic signatures.

Custom multi‑tumor next‑generation sequencing panel for routine molecular diagnosis of solid tumors: Validation and results from three‑year clinical use

Molecular testing is extremely important in cancer care, starting as early as at diagnosis. In order to address the challenge of providing reliable results within the timeframe adapted to patient management and suitable to guide clinical decisions, a capture-based next-generation sequencing (NGS) panel focusing on ten genes known to harbor genetic variations which may be targeted by approved drugs in patients with cancer was designed and validated. Very favorable analytical performances were obtained for both solid and liquid biopsies. For solid biopsies, a low read depth (80X per nucleotide) led to the genotype detection accuracy of 100%. The read of raw data for liquid biopsies resulted in the 91.19% result concordance between paired solid and liquid samples. The present method met all the requirements for the ISO15189 certification. During our three-year experience of routinely using this panel, almost 2,300 samples from lung and colorectal cancers, melanomas and gastrointestinal stromal tumors have been analyzed. It was found that our panel detected slightly more gain-of-function variants than described in the literature. Surprisingly, loss-of-function variants were also detected in certain of the analyzed genes. Finally, liquid biopsy data revealed statistically different mutated allele frequencies between tumor types, but also between mutated genes and variants themselves. In conclusion, the use of our capture-based NGS panel is perfectly adapted to perform relevant molecular diagnosis in a time frame compatible with patient care.

Intestinal Akkermansia muciniphila predicts clinical response to PD-1 blockade in patients with advanced non-small-cell lung cancer

Aside from PD-L1 expression, biomarkers of response to immune checkpoint inhibitors (ICIs) in non-small-cell lung cancer (NSCLC) are needed. In a previous retrospective analysis, we documented that fecal Akkermansia muciniphila (Akk) was associated with clinical benefit of ICI in patients with NSCLC or kidney cancer. In the current study, we performed shotgun-metagenomics-based microbiome profiling in a large cohort of patients with advanced NSCLC (n = 338) treated with first- or second-line ICIs to prospectively validate the predictive value of fecal Akk. Baseline stool Akk was associated with increased objective response rates and overall survival in multivariate analyses, independent of PD-L1 expression, antibiotics, and performance status. Intestinal Akk was accompanied by a richer commensalism, including Eubacterium hallii and Bifidobacterium adolescentis, and a more inflamed tumor microenvironment in a subset of patients. However, antibiotic use (20% of cases) coincided with a relative dominance of Akk above 4.8% accompanied with the genus Clostridium, both associated with resistance to ICI. Our study shows significant differences in relative abundance of Akk that may represent potential biomarkers to refine patient stratification in future studies.

Does large NGS panel analysed using exome tumour sequencing improve the management of advanced non-small-cell lung cancers?

INTRODUCTION

Non-small-cell lung cancer (NSCLC) is one of the most common and deadly cancers. Several molecular drivers of oncogene addiction are now known to be strong predictive biomarkers for target therapies. Advances in large Next Generation Sequencing (LNGS) have improved the ability to detect potentially targetable mutations. However, the integration of LNGS into clinical management in an individualized manner remains challenging.

METHODS

In this single-center observational study we included all patients with advanced NSCLC who underwent LNGS. Somatic and germline exome analysis was performed with a restriction on 323 cancer related genes. Variants were classified and Molecular Tumour Board (MTB) made therapeutic propositions.

RESULTS

We performed LNGS analysis in 281 patients with advanced NSCLC between March 2015 and January 2018. Technical failure occurred in only 3% of cases. Three hundred and fifty-six targetable mutations were detected. At least one targetable mutation was found in 209 patients. For all these patients, the MTB was able to recommend treatment with a targeted agent based on the evaluation of the tumour's genetic profile and treatment history. Twenty-nine patients (13.9%) were subsequently treated with an MTB-recommended targeted therapy. We did not observe any improvement in terms of clinical benefit for these patients.

CONCLUSIONS

In this case series, we show that including LNGS into routine clinical management was feasible but does not appear to provide clinical benefit in the management of patients with advanced NSCLC.

An Algorithm Combining Patient Performance Status, Second Hit Analysis, PROVEAN and Dann Prediction Tools Could Foretell Sensitization to PARP Inhibitors in Digestive, Skin, Ovarian and Breast Cancers

Simple Summary

PARP inhibitors, a family of targeted cancer therapeutics, have been shown to be efficient in patients with some deficiencies in the homologous recombination machinery. However, a quick and reliable identification of patients who would benefit from such therapies remains a challenge. In particular, patients with tumors carrying variants of unknown significance (VUS) in homologous recombination genes do not currently benefit from PARP inhibitor treatments. In this study, we present an algorithm that may allow classification of these variants with regard to their impact on tumor responsiveness to PARP inhibitors. If validated on a larger patient sample, our algorithm would allow patients with tumors potentially responsive to PARP inhibitors to benefit from this therapy.

Abstract

PARP inhibitors yield interesting outcomes for patients with ovarian tumors harboring BRCA1 or BRCA2 mutation, but also with other tumors with homologous repair (HR) deficiency. About 40% of variants are variants of unknown significance (VUS), blocking the use of PARP inhibitors. In this study, we analyzed NGS data from 78 metastatic patients treated with PARP inhibitors. We tested NGS data and in silico predictions to classify VUS as potentially benign or deleterious. Among 41 patients treated with olaparib, three had tumors harboring benign and 26 pathogenic variants, while 12 had VUS. Progression-Free Survival (PFS) analysis showed that benign variants did not respond to olaparib whereas pathogenic variants were associated with a median PFS of 190 days. Surprisingly, median PFS of patients with VUS-carrying tumors suggested that some of them may be sensitive to PARP inhibitors. By testing different in silico predictions and variant allelic frequency, we obtained an algorithm predicting VUS sensitivity to PARP inhibitors for patients with a Performance Status below 3. Our work suggests that VUS in HR genes could be predicted as benign or deleterious, which may increase the number of patients eligible for PARP inhibitor treatment. Further studies in a larger sample are warranted to validate our prediction algorithm.

The Tumor Microenvironment Impairs Th1 IFNγ Secretion through Alternative Splicing Modifications of Irf1 Pre-mRNA

It is clearly established that the immune system can affect cancer response to therapy. However, the influence of the tumor microenvironment (TME) on immune cells is not completely understood. In this respect, alternative splicing is increasingly described to affect the immune system. Here, we showed that the TME, via a TGFβ-dependent mechanism, increased alternative splicing events and induced the expression of an alternative isoform of the IRF1 transcription factor (IRF1Δ7) in Th1 cells. We found that the SFPQ splicing factor (splicing factor, proline- and glutamine-rich) was responsible for the IRF1Δ7 production. We also showed, in both mice and humans, that the IRF1 alternative isoform altered the full-length IRF1 transcriptional activity on the Il12rb1 promoter, resulting in decreased IFNγ secretion in Th1 cells. Thus, the IRF1Δ7 isoform was increased in the TME, and inhibiting IRF1Δ7 expression could potentiate Th1 antitumor responses.

PARP inhibitor resistance and TP53 mutations in patients treated with olaparib for BRCA-mutated cancer: Four case reports

Loss‑of‑function BRCA mutations are frequent in high‑grade serous ovarian carcinoma. BRCA1 and ‑2 mutations lead to homologous recombination (HR) deficiency. Poly(ADP‑ribose) polymerases (PARP) are enzymes involved in DNA repair. PARP inhibitors (PARPi) lead to DNA damage accumulation in cells deficient in HR. Olaparib (a PARPi) is currently used for the treatment of high‑grade serous ovarian carcinoma with germline or somatic BRCA mutations; however, numerous patients do not respond or eventually develop resistance to these agents. The TP53 gene encodes the p53 protein, which is often referred to as the 'guardian of the genome'. TP53 mutations at diagnosis are known to promote resistance to chemotherapy. In the present study, four cases of patients with BRCA‑mutated cancer treated with olaparib, who progressed following the PARPi treatment, are reported. Exome analyses were performed on a primary tumor biopsy at diagnosis, then on a progressing metastasis following olaparib treatment. Exome analyses following olaparib treatment identified de novo TP53 mutations, as well as increased frequencies of pre‑existing TP53 mutations compared with the primary tumor. In HCT116 TP53^‑/‑ cells carrying BRCA2 pathogenic mutations, TP53 inactivating mutations were associated with lower sensitivity to olaparib in vitro. Thus, inactivating TP53 mutations may be associated to olaparib resistance in the presence of BRCA mutations. In conclusion, the present findings demonstrated resistance to PARPi with de novo TP53 mutations that may be clinically relevant. As TP53 mutations are easily detectable with targeted next‑generation sequencing panels, these may serve as surrogate markers for the onset of PARPi resistance in the context of routine patient management strategies.

Cleaved Caspase-3 Transcriptionally Regulates Angiogenesis-Promoting Chemotherapy Resistance

Caspases are well known for their role in apoptosis. Recently, nonapoptotic roles of caspases have been identified, however, these noncanonical roles are not well documented and the mechanisms involved are not fully understood. Here, we studied the role of cleaved caspase-3 using human- and mouse-proficient caspase-3 cancer cell lines and human-deficient caspase-3 cancer cells. Cleaved caspase-3 functioned as a transcription factor and directly bound to DNA. A DNA-binding domain was identified in the small subunit of caspase-3 and an active conformation was essential for caspase-3 transcriptional activity. Caspase-3 DNA binding enhanced angiogenesis by upregulating the expression of proangiogenic genes and by activating pathways that promoted endothelial cell activation. Some proapoptotic genes were downregulated in caspase-3-proficient cells. Inhibiting caspase-3 increased the efficacy of chemotherapy and decreased spontaneous tumor development. These data highlight a novel nonapoptotic role of caspase-3 and suggest that cleaved caspase-3 could be a new therapeutic target in cancer. SIGNIFICANCE: These findings report a noncanonical function of caspase-3 by demonstrating its ability to transcriptionally regulate the VEGFR pathway.

Prediction of olaparib sensitivity for variants of unknown significance in homologous repair genes

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Background: the recent use of PARP inhibitors in clinical practice gives very interesting outcome for ovary tumors with BRCA1 or BRCA2 mutation but also in other tumors with homologous repair deficiency. Nevertheless, no hotspot mutations are present, consequently, more than 85% of observed variants have unknown significance, blocking the use of PARP inhibitor. Methods: Exome analysis was performed on a cohort of 27 patients treated with olaparib. After bioinformatics analyses, variant interpretation was performed by interrogating different databases. For variants of unknown significance (VUS), PROVEAN software and allelic frequency normalized with tumor cellular content were used to classify VUS as potentially benign or potentially deleterious. Results: Among the 27 patients analyzed, 16 harbored already classified variants (3 benign and 13 pathogen variants) and 11 had VUS. The first Progression Free Survival (PFS) analysis showed that benign variants did not respond to olaparib with a median survival of 62 days, whereas pathogenic variants had a median of 109 days. Surprisingly, VUS had a median of 136 days, suggesting that some of them could be classified as potentially deleterious. On the subset of 11 patients with VUS, we applied PROVEAN prediction classifying 5 variants as benign and 6 variants as deleterious, with a median PFS of 54 days and 140 days ( p=0.3235), respectively. With the second prediction, based on variant allelic frequency, we obtained PFS of 73.5 months for benign variants and 210 days for deleterious ones ( p=0.29). By combining both predictions, we classified as benign, VUS predicted benign with both predictions, and as deleterious, VUS predicted as deleterious with at least one prediction. Consequently, we perfectly discriminated benign from deleterious variants with a median PFS of 36 days for predicted benign and 177 days for predicted deleterious ( p=0.0084). From all patients, PFS were significantly different ( p=0.0003) between benign (n=6, 56 days) and deleterious variants (n=21, 140 months). Conclusions: Our work tends to show that VUS of homologous repair genes could be predicted as benign or deleterious, and could increase the number of patients eligible for a treatment by PARP inhibitors. The number of patients needs to be increased in order to validate our prediction algorithm.

Transcriptome-wide identification of transient RNA G-quadruplexes in human cells

Guanine-rich RNA sequences can fold into four-stranded structures, termed G-quadruplexes (G4-RNAs), whose biological roles are poorly understood, and in vivo existence is debated. To profile biologically relevant G4-RNA in the human transcriptome, we report here on G4RP-seq, which combines G4-RNA-specific precipitation (G4RP) with sequencing. This protocol comprises a chemical crosslinking step, followed by affinity capture with the G4-specific small-molecule ligand/probe BioTASQ, and target identification by sequencing, allowing for capturing global snapshots of transiently folded G4-RNAs. We detect widespread G4-RNA targets within the transcriptome, indicative of transient G4 formation in living human cells. Using G4RP-seq, we also demonstrate that G4-stabilizing ligands (BRACO-19 and RHPS4) can change the G4 transcriptomic landscape, most notably in long non-coding RNAs. G4RP-seq thus provides a method for studying the G4-RNA landscape, as well as ways of considering the mechanisms underlying G4-RNA formation, and the activity of G4-stabilizing ligands.

Exome Analysis Reveals Genomic Markers Associated with Better Efficacy of Nivolumab in Lung Cancer Patients

PURPOSE

Immune checkpoint inhibitors revolutionized the treatment of non-small cell lung cancer (NSCLC). However, only one-quarter of patients benefit from these new therapies. PD-L1 assessment and tumor mutational burden (TMB) are available tools to optimize use of checkpoint inhibitors but novel tools are needed. Exome sequencing could generate many variables but their role in identifying predictors of response is unknown.

EXPERIMENTAL DESIGN

We performed somatic and constitutional exome analyses for 77 patients with NSCLC treated with nivolumab. We studied: one-tumor-related characteristics: aneuploidy, CNA clonality, mutational signatures, TMB, mutations in WNT, AKT, MAPK, and DNA repair pathways, and two-immunologic characteristics: number of intratumoral TCR clones, HLA types, and number of neoantigens; and six clinical parameters.

RESULTS

A high TMB per Mb, a high number of neoantigens, mutational signatures 1A and 1B, mutations in DNA repair pathways, and a low number of TCR clones are associated with greater PFS. Using a LASSO method, we established an exome-based model with nine exome parameters that could discriminate patients with good or poor PFS (P < 0.0001) and overall survival (P = 0.002). This model shows better ability to predict outcomes compared with a PD-L1 clinical model with or without TMB. It was externally validated on two cohorts of patients with NSCLC treated with pembrolizumab or with nivolumab and ipilimumab as well as in urothelial tumors treated with atezolizumab.

CONCLUSIONS

Altogether, these data provide a validated biomarker that predicts the efficacy of nivolumab or pembrolizumab in patients with NSCLC. Our biomarker seems to be superior to PD-L1 labeling and TMB models.

The transfer of multigene panel testing for hereditary breast and ovarian cancer to healthcare: What are the implications for the management of patients and families?

Until recently, the molecular diagnosis of hereditary breast and ovarian cancer (HBOC) was mostly based on BRCA1/2 testing. Next generation sequencing and the recent discovery of new genes involved in HBOC now permit the transfer of genomic capture targeting multiple candidate genes from research to clinical use. However, the implications for the management of patients and their families have not been extensively studied, in particular since some of these genes are not well-established cancer predisposing genes. We studied 583 consecutive patients from Burgundy (France) fulfilling the criteria for BRCA testing using a next generation sequencing 25-genes panel including 20 well-established high-risk cancer genes as well as more recently identified predisposing HBOC cancer. A pathogenic BRCA1/2 mutation was found in 51 patients (9%). Besides, we found 37 pathogenic or likely pathogenic mutations in 10 different high to low-risk genes in 34 patients (6%). The most frequently mutated genes were CHEK2 (n = 12; 2%), ATM (n = 9; 1.5%), and PALB2 (n = 4; 0.6%). Three patients had a mutation in two different predisposing genes. The analysis of clinical actionability conducted in mutation-positive individuals revealed that additional disease-specific screening and/or prevention measures beyond those based on personal and family history alone had been recommended in 69% of cases. In conclusion, multigene panel testing is a powerful tool to identifying high to low-risk HBOC susceptibility genes. The penetrance and spectrum of cancers with these other genes are sometimes undefined, and further collaborative work is crucial to address this question.

Use of dedicated gene panel sequencing using next generation sequencing to improve the personalized care of lung cancer

Advances in Next Generation Sequencing (NGS) technologies have improved the ability to detect potentially targetable mutations. However, the integration of NGS into clinical management in an individualized manner remains challenging. In this single-center observational study, we performed a dedicated NGS panel studying 41 cancer-related genes in 50 consecutive patients with metastatic non-small-cell lung cancer between May 2012 and October 2014. Molecular analysis could be performed in 48 patients with a good quality check. One hundred and thirty-three mutations, whose twenty-four unique mutations, were detected. At least one mutation was found in 46 patients. In 58% of cases, the Molecular Tumor Board (MTB) was able to recommend treatment with a targeted agent based on the evaluation of the tumor genetic profile and treatment history. Nine patients (18%) were subsequently treated with a MTB-recommended targeted therapy; four patients experienced a clinical benefit with a partial response or stabilization lasting more than 4 months. In this case series involving patients with metastatic non-small cell lung cancer, we show that including integrative clinical sequencing data into routine clinical management was feasible and could impact on patient therapeutic proposal.

Docetaxel-titanate nanotubes enhance radiosensitivity in an androgen-independent prostate cancer model

Around 40% of high-risk prostate cancer patients who undergo radiotherapy (RT) will experience biochemical failure. Chemotherapy, such as docetaxel (DTX), can enhance the efficacy of RT. Multidrug resistance mechanisms often limit drug efficacy by decreasing intracellular concentrations of drugs in tumor cells. It is, therefore, of interest to develop nanocarriers of DTX to maintain the drug inside cancer cells and thus improve treatment efficacy. The purpose of this study was to investigate the use of titanate nanotubes (TiONts) to develop a TiONts-DTX nanocarrier and to evaluate its radiosensitizing in vivo efficacy in a prostate cancer model. In vitro cytotoxic activity of TiONts-DTX was evaluated using an MTS assay. The biodistribution of TiONts-DTX was analyzed in vivo by single-photon emission computed tomography. The benefit of TiONts-DTX associated with RT was evaluated in vivo. Eight groups with seven mice in each were used to evaluate the efficacy of the nanohybrid combined with RT: control with buffer IT injection ± RT, free DXL ± RT, TiONts ± RT and TiONts-DXL ± RT. Mouse behavior, health status and tumor volume were monitored twice a week until the tumor volume reached a maximum of 2,000 mm³. More than 70% of nanohybrids were localized inside the tumor 96 h after administration. Tumor growth was significantly slowed by TiONts-DTX associated with RT, compared with free DTX in the same conditions (P=0.013). These results suggest that TiONts-DTX improved RT efficacy and might enhance local control in high-risk localized prostate cancer.

Efficiency of olaparib in colorectal cancer patients with an alteration of the homologous repair protein

Precision medicine is defined by the administration of drugs based on the tumor’s particular genetic characteristics. It is developing quickly in the field of cancer therapy. For example, KRAS, NRAS and BRAF genetic testing demonstrates its efficiency for precision medicine in colorectal cancer (CRC). Besides for these well-known mutations, the purpose of performing larger genetic testing in this pathology is unknown. Recent reports have shown that using the poly ADP ribose polymerase (PARP) inhibitor olaparib in patients with homologous repair enzyme deficiency gave positive clinical results in breast, ovarian and prostate cancers. We have reported here the cases of 2 patients with multi-treated metastatic CRC who underwent somatic and constitutional exome analyses. The analyses revealed a loss of function mutation in a homologous repair enzyme resulting in the loss of heterozygosity for both patients (Check2 for the first patient and RAD51C for the second one). Both patients were treated with off-label usage of olaparib. While the first patient showed clinical benefit, reduction of carcinoembryonic antigen tumor marker and radiologic response, the second patient quickly presented a progression of the tumor. Additional genetic analyses revealed a frameshift truncating mutation of the TP53BP1 gene in the patient who progressed. Interestingly, deficiency in TP53BP1 was previously described to confer resistance to olaparib in mice breast cancer models. Our findings suggest that exome analysis may be a helpful tool to highlight targetable mutations in CRC and that olaparib may be efficient in patients with a homologous repair deficiency.

Transcriptional expression of 8 genes predicts pathological response to first-line docetaxel + trastuzumab-based neoadjuvant chemotherapy

BACKGROUND

Overexpression of HER2 is observed in 20 to 30% of breast carcinomas. The use of trastuzumab has improved the treatment of these patients, especially when it is associated with docetaxel. To optimize the use of this treatment, it seems important to select putative complete responders before treatment administration.

METHODS

In this study, we analyzed by quantitative PCR the expression of 28 genes in HER2-overexpressing tumors treated with trastuzumab + docetaxel-based chemotherapy. We then correlated their expression profile with those of trastuzumab-sensitive and resistant cell lines to classify tumors as having a sensitive (pCR) or resistant (non-pCR) profile. Finally, we used public datasets from the GEO website to validate the reduced gene-expression profile obtained.

RESULTS

We identified an 8-gene-expression combination that predicted the response to treatment with an accuracy of 76%. Based on public microarray data, we showed that the expression profile was specific to first-line trastuzumab + docetaxel-based treatment with an accuracy of 85%.

CONCLUSIONS

Our results showed that by profiling the expression of 8 genes it was possible to predict the response to first-line trastuzumab + docetaxel-based chemotherapy. The use of cancer cell lines as the reference allowed a proper fit with the specificity of different tissues, such as lung or gastric cancers, which could also be eligible to concomitant HER2 inhibition by treatment with trastuzumab or tyrosine kinase inhibitors and docetaxel.

Preclinical development of a docetaxel nanocarrier to enhance prostate cancer radiosensitivity

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Background: From 30% to 50% of high risk prostate cancer patients who undergo radiation therapy (RT) will have a biochemical failure. Combining chemotherapy, such as Docetaxel (DXL), with RT can enhance its efficiency. Multidrug resistance mechanisms often limit drug efficacy by decreasing tumor cell intracellular concentration of drugs. There is interest to develop nanocarrier of DXL to maintain drug inside cancer cells by improving its efficacy. The purpose of this study was to develop a titanate-nanotube (TiONt)-DXL nanocarrier (nanohybrid) and to evaluate its in vivobiodistribution as well as its radiosensitizing efficacy in association with RT on a hormone-independent prostate cancer model. Methods: DXL molecules were grafted on TiONts using PEG-3000 molecules to generate the nanohybrid. In vitrocytotoxic activity of the nanohybrid was evaluated on PC-3 cell line using MTS assay. After intratumoral injection, biodistribution analysis was performed by SPEC-CT imaging of mice bearing subcutaneous PC-3 human prostate tumors. To evaluate the benefit of nanohybrid and RT association, tumors were irradiated using 3 fractions of 4Gy administrated after the injection of nanohybrids. Nine groups of 7 mice were used to evaluate nanohybrid and RT association efficacy : untreated, control with buffer IT injection, +/- RT, free DXL, +/- RT, TiONt +/- RT and TiONt-DXL +/- RT. Mice behavior, health status and tumor volume were monitored twice a week until tumor growth recovery. Results: Biodistribution kinetics showed that more than 70% of nanohybrids were localized into the tumor 96 hours after injection. Mice receiving nanohybrid-RT exhibited a significant tumor growth delay to reach a volume of 1,000mm3compared to mice receiving free DXL-RT: 73.7 days (median, [58.9-89]) vs 56 days (median, [31.5-74]) (p=0.0127). Conclusions: TiONt-DXL improves RT efficacy compared to free DXL. These results suggest that local control might be enhanced by TiONt-DXL. TiONt-DXL can be injected as a radiosensitizer in men harboring high risk localized prostate cancer with needles during prostate brachytherapy procedure.

gDNA enrichment by a transposase-based technology for NGS analysis of the whole sequence of BRCA1, BRCA2, and 9 genes involved in DNA damage repair

The widespread use of Next Generation Sequencing has opened up new avenues for cancer research and diagnosis. NGS will bring huge amounts of new data on cancer, and especially cancer genetics. Current knowledge and future discoveries will make it necessary to study a huge number of genes that could be involved in a genetic predisposition to cancer. In this regard, we developed a Nextera design to study 11 complete genes involved in DNA damage repair. This protocol was developed to safely study 11 genes (ATM, BARD1, BRCA1, BRCA2, BRIP1, CHEK2, PALB2, RAD50, RAD51C, RAD80, and TP53) from promoter to 3'-UTR in 24 patients simultaneously. This protocol, based on transposase technology and gDNA enrichment, gives a great advantage in terms of time for the genetic diagnosis thanks to sample multiplexing. This protocol can be safely used with blood gDNA.

Next-generation sequencing analysis of lung and colon carcinomas reveals a variety of genetic alterations

The development of targeted therapies in cancer has accelerated the development of molecular diagnosis. This new cancer discipline is booming, with an increasing number of gene alterations to analyze in a growing number of patients. To deal with this fast-developing activity, current analysis techniques (Sanger sequencing, allelic discrimination and high resolution melting) take more and more time. In recent years, next generation sequencing (NGS) technologies have appeared and given new perspectives in oncology. In this study, we analyzed FFPE lung and colon carcinomas using the Truseq Cancer Panel, which analyzes the mutation hotspots of 48 genes. We also tested the use of whole-genome amplification before NGS analysis. NGS results were compared with the data obtained from routine diagnosis. All of the alterations routinely observed were identified by NGS. Moreover, NGS revealed mutations in the KRAS and EGFR genes in patients diagnosed as wild-type by routine techniques. NGS also identified concomitant mutations in EGFR and KRAS or BRAF mutations, and a 15-nt deletion in exon 19 of EGFR in colon carcinomas. The study of the other genes sequenced in the Panel revealed 14 genes altered by 27 different mutations and three SNP with a possible role in cancer susceptibility or in the response to treatment. In conclusion, this study showed that NGS analysis could be used for the analysis of gDNA extracted from FFPE tissues. However, given the high sensitivity of this technology, high-throughput clinical trials are needed to confirm its reliability for the molecular diagnosis of cancer.

Only missense mutations affecting the DNA binding domain of p53 influence outcomes in patients with breast carcinoma

The presence of a TP53 gene mutation can influence tumour response to some treatments, especially in breast cancer. In this study, we analysed p53 mRNA expression, LOH at 17p13 and TP53 mutations from exons 2 to 11 in 206 patients with breast carcinoma and correlated the results with disease-free and overall survival. The observed mutations were classified according to their type and location in the three protein domains (transactivation domain, DNA binding domain, oligomerization domain) and correlated with disease-free and overall survival. In our population, neither p53 mRNA expression nor LOH correlated with outcome. Concerning TP53 mutations, 27% of tumours were mutated (53/197) and the presence of a mutation in the TP53 gene was associated with worse overall survival (p = 0.0026) but not with disease-free survival (p = 0.0697), with median survival of 80 months and 78 months, respectively. When alterations were segregated into mutation categories and locations, and related to survival, tumours harbouring mutations other than missense mutations in the DNA binding domain of P53 had the same survival profiles as wild-type tumours. Concerning missense mutations in the DNA binding domain, median disease-free and overall survival was 23 months and 35 months, respectively (p = 0.0021 and p<0.0001, respectively), compared with 78 and 80 months in mutated tumours overall. This work shows that disease-free and overall survival in patients with a frameshift mutation of TP53 or missense mutation in the oligomerization domain are the same as those in wild-type TP53 patients.

Human herpes virus co-infection is associated with mortality in HIV-negative patients with Pneumocystis jirovecii pneumonia

The purpose of this investigation was to characterize the management and prognosis of severe Pneumocystis jirovecii pneumonia (PJP) in human immunodeficiency virus (HIV)-negative patients. An observational cohort study of HIV-negative adults with PJP documented by bronchoalveolar lavage (BAL) through Gomori-Grocott staining or immunofluorescence, admitted to one intensive care unit (ICU) for acute respiratory failure, was undertaken. From 1990 to 2010, 70 patients (24 females, 46 males) were included, with a mean age of 58.6 ± 18.3 years. The mean Simplified Acute Physiology Score (SAPS)-II was 36.9 ± 20.4. Underlying conditions included hematologic malignancies (n = 21), vasculitis (n = 13), and solid tumors (n = 13). Most patients were receiving systemic corticosteroids (n = 63) and cytotoxic drugs (n = 51). Not a single patient received trimethoprim-sulfamethoxazole as PJP prophylaxis. Endotracheal intubation (ETI) was required in 42 patients (60.0 %), including 38 with acute respiratory distress syndrome (ARDS). In-ICU mortality was 52.9 % overall, reaching 80.9 % and 86.8 %, respectively, for patients who required ETI and for patients with ARDS. In the univariate analysis, in-ICU mortality was associated with SAPS-II (p = 0.0131), ARDS (p < 0.0001), shock (p < 0.0001), and herpes simplex virus (HSV) or cytomegalovirus (CMV) on BAL (p = 0.0031). In the multivariate analysis, only ARDS was associated with in-ICU mortality (odds ratio [OR] 23.4 [4.5-121.9], p < 0.0001). PJP in non-HIV patients remains a serious disease with high in-hospital mortality. Pulmonary co-infection with HSV or CMV may contribute to fatal outcome.

Apoptosis gene signature of Survivin and its splice variant expression in breast carcinoma

Survivin, an anti-apoptotic protein, was described as strongly expressed in human cancers including breast cancer. However, little is known about the association between Survivin variants (Survivin-2B, Survivin-ΔEx3, Survivin-3B, and Survivin-2α) and the other apoptotic-related genes. In this study, we analyzed the apoptosis gene signature of Survivin and its variant expression in breast cancer. Human Apoptosis Gene Arrays were used to screen genes that could be associated with Survivin variants. Expression of the five transcripts was measured by RT-PCR in 135 breast carcinomas and Cox survival analysis was analyzed according to the patient outcome. Significant associations between Survivin transcripts and apoptotic genes were found. Interestingly, Survivin-3B variant showed major inverse correlations with pro-apoptotic genes. In addition, in vitro results indicated that overexpression of Survivin-3B strongly inhibits 5-fluorouracil/epirubicin/cyclophosphamide-induced apoptosis in breast tumor cell lines. In breast carcinomas, uni- and multivariate analysis showed patients with high level of Survivin-3B expression had a shorter overall (P=0.030 and P=0.042 respectively), and disease-free (P=0.024 and P=0.009) survival. Our data suggest that Survivin-3B contributes to cell survival through the anti-apoptotic pathway and that its expression level could be an important factor in determining therapeutic strategies for breast carcinoma.

[Recurrent tick-borne fever: a possible diagnosis in patients returning from Senegal]

In Senegal, tick-borne relapsing fever caused by the spirochetes Borrelia crucidurae is the most common cause of fever after malaria in rural areas. However, this is only rarely diagnosed in France, probably because: i) the diagnosis relies on investigations that are not routinely done; ii) even undiagnosed, borreliosis may be cured with empirical antibiotic treatment. We report four observations of tick-borne relapsing fever in patients returning from Senegal: In two patients, the diagnosis relied on the observation of spirochetes in blood smears; in the other two, the diagnosis relied on typical clinico-biological signs, borreliosis serology and exposure. These four cases diagnosed over a four year period in one institution suggest that relapsing fever is not rare in patients returning from West Africa. Patients who return form Senegal with unexplained fever should be investigated with careful examination of blood smears and PCR on blood samples.

The expression of BIRC5 is correlated with loss of specific chromosomal regions in breast carcinomas

Expression of BIRC5 (survivin), a member of the inhibitor of apoptosis protein (IAP) family, is elevated in fetal tissues and in various human cancers. Mechanisms up-regulating BIRC5 in cancer are poorly understood. Here, we show that overexpression of BIRC5 induces a high proliferation level in MCF-7 breast tumor cells. In a population of 191 breast carcinomas, BIRC5 expression is not affected by BIRC5 promoter polymorphism at -31, or BIRC5 gene copy number. However, a significant correlation was found between expression of demethylase (dMTase) and expression of BIRC5. In addition, among 13 chromosomal regions tested for allelic loss [loss of heterozygosity (LOH)], two regions close to D3S1478 and D6S264 were related to BIRC5 expression. In tumors with LOH at D3S1478 and/or D6S264, BIRC5 expression was significantly increased. These regions have been suggested to harbor tumor suppressor genes and/or common fragile sites that may play a role in increasing genetic instability. These results suggest that genes located near D3S1478 and D6S264 might work by inhibiting, directly or indirectly, BIRC5 expression and thus their loss leads to its up-regulation. In addition, BIRC5 expression may induce breast tumor proliferation by promoting genetic instability. This article contains Supplementary Material available at http://www.interscience.wiley.com/jpages/1045-2257/suppmat.

[Finding of Strongyloides stercoralis infection, 25 years after leaving the endemic area, upon corticotherapy for ocular trauma]

In the field of ophthalmology, indications for high-dose corticotherapy are various. This paper reports the case of a Caledonian man who presented with intestinal strongyloidiasis, discovered 25 years after he had left the endemic area. A checkup before corticotherapy for traumatic retina edema provided the diagnosis of the infection. The authors emphasize the importance of searching for Strongyloidiasis stercoralis larva before initiating corticotherapy, as it is the main treatment responsible for parasitic dissemination. The most severe form of strongyloidiasis, the disseminated form, has a high mortality rate: 70%-90%. The definitive diagnostic test is enhanced larva recovery, which should be proposed to every patient returning from endemic area, people with precarious hygiene or with high eosinophilia or intestinal symptoms of chronic infection. Delay in diagnosing strongyloidiasis frequently results in death, despite vigorous treatment.

Comparison of epidemiological, clinical, and biological features of invasive aspergillosis in neutropenic and nonneutropenic patients: a 6-year survey

BACKGROUND

Invasive aspergillosis is an opportunistic infection that occurs mainly among patients with prolonged neutropenia. Few data are available on invasive aspergillosis in nonneutropenic patients.

METHODS

The aim of this survey was to compare neutropenic and nonneutropenic patients who had received a diagnosis of invasive aspergillosis at our institution during a 6-year period.

RESULTS

Among the 88 cases of invasive aspergillosis analyzed here, 12 were histologically proven, 52 were probable, and 24 were possible. Forty-seven percent of cases were diagnosed in the intensive care unit, and 40% were diagnosed in hematology units. Neutropenia was a risk factor for 52 patients (59%), most of whom had hematological or solid malignancies. Among the 36 nonneutropenic patients (41%), the main underlying conditions were steroid-treated chronic obstructive pulmonary disease, asthma, rheumatoid arthritis, giant-cell arteritis, and microvascular disorders; 10 patients were recipients of solid-organ transplants, and 1 patient was seropositive for human immunodeficiency virus. The distribution of proven and probable invasive aspergillosis was similar for neutropenic and nonneutropenic patients. The mortality rate was 71.5% overall and was significantly higher among nonneutropenic patients than among neutropenic patients (89% vs. 60%; P<.05). Compared with neutropenic patients, nonneutropenic patients were significantly less likely to have symptoms of invasive aspergillosis and more likely to have frequent intercurrent pneumonia due to another microorganism. The sensitivity of mycological examination of bronchoalveolar lavage fluid specimens was higher for nonneutropenic patients than for neutropenic patients (85% vs. 58%; P<.05), whereas the sensitivity of antigenemia was the same for the 2 populations (65% vs. 64%). Findings on thoracic computed tomographs were similar, except that segmental areas of consolidation occurred more frequently among neutropenic patients.

CONCLUSION

This survey at a whole institution underlines the high number of cases of invasive aspergillosis among nonneutropenic patients, with an overall mortality rate that was significantly higher than that for neutropenic patients.

Infections à cryptocoque chez des patients non VIH. À propos de quatre cas et revue de la littérature

BACKGROUND

Cryptococcal infections are frequent in HIV-infected patients and are regularly looked after. This infection may occur in others immunosuppressives situations and, in those cases, diagnosis is often delayed.

METHODS

We report four cases of cryptococcal infections in patients whose immunosuppression isn't related with HIV infection but due to chronic lymphocytic leukemia, giant cell temporal arteritis, gastric neoplasm and lupus. Diagnosis, prognostic and treatment are detailed.

RESULTS

Four patients aged from 25 to 76 presented a cryptococcal infection (three meningitis). A woman died at the admission. Another died seven years later. The two others are still alive under treatment. When infected, all patients were immunodeficiency.

CONCLUSION

Cryptococcal infection may occur in patients non-HIV-infected patients. Early detection is needed to improve prognostic.

[Post-inflammatory cutis laxa. A case report]

Cutis laxa (CL) is a rare disorder in which the skin hangs in loose fields, so that affected individuals appear to be prematurely aged. The changes are more evident when effect the face with a prematurely-aged appearance. The acute form follows an inflammatory skin lesions. Its aetiology is not well known. We report a case of a head acute CL of a 17 years patient, secondary to a generalized skin eruption. The prematurely-aged appearance concern especially forehead, ear lobes and nasolabial folds. A two stages surgical treatment has associated: a forehead lifting associated to a Coleman lipofilling and an ear lobe reduction, a secondary Coleman lipofilling of the nasolabial folds. The skin biopsy confirm the diagnosis. The correction is stable and satisfactory after one year. The confrontation of our findings to those previously described confirm complexity of diagnosis and histological observations of this rare disorder.

Breast feeding after reduction mammaplasty performed during adolescence

Reduction mammaplasty (RM) can be performed during adolescence if the functional capacity of the breast is preserved. Future breast feeding must be carefully considered in the therapeutic decision making process.

PURPOSE OF THE STUDY

Breast feeding after reduction mammaplasty performed during adolescence was assessed to determine surgical factors influencing outcome and patient reception of information concerning breast feeding.

METHODS

A questionnaire was sent to 109 women who had undergone reduction mammaplasty between 1981 and 1997 when they were 15-17 years old to ascertain their reasons for having surgery, their satisfaction, and their attitude towards breast feeding.

RESULTS

Sixty-five questionnaires (60%) could be analyzed. Mean delay since surgery was 8.1 years. Seventeen women (26%) had delivered 25 infants (mean 1.5). Mean delay after surgery to first delivery was 7.68 years. Five women (29%) nursed their first infant for a mean 11.3 days. None of the women interrupted breast feeding for a reason related to a nipple anomaly or difficult sucking. Twelve women (71%) did not nurse their first infant, because of the prior breast surgery for six of them. Among the 48 nulliparous women, 24 (50%) stated they would nurse their future infant. Although information on breast feeding was systematically delivered, 41 women (63%) stated they had not been informed. There was no statistical relationship between breast feeding and degree of satisfaction, patient-assessed scar quality, or nipple disorders.

CONCLUSION

Adolescents who undergo reduction mammaplasty can nurse their future infants with a complication rate similar to that in the general population. Special attention must be given to delivery of information on breast feeding.