A G-quadruplex-binding platinum complex induces cancer mitochondrial dysfunction through dual-targeting mitochondrial and nuclear G4 enriched genome.

BACKGROUND: G-quadruplex DNA (G4) is a non-canonical structure forming in guanine-rich regions, which play a vital role in cancer biology and are now being acknowledged in both nuclear and mitochondrial (mt) genome. However, the impact of G4-based targeted therapy on both nuclear and mt genome, affecting mt function and its underlying mechanisms remain largely unexplored. METHODS: The mechanisms of action and therapeutic effects of a G4-binding platinum(II) complex, Pt-ttpy, on mitochondria were conducted through a comprehensive approaches with in vitro and in vivo models, including ICP-MS for platinum measurement, PCR-based genetic analysis, western blotting (WB), confocal microscope for mt morphology study, extracellular flux analyzer, JC1 and Annexin V apoptosis assay, flow cytometry and high content microscope screening with single-cell quantification of both ROS and mt specific ROS, as well as click-chemistry for IF study of mt translation. Decipher Pt-ttpy effects on nuclear-encoded mt related genes expression were undertaken via RNA-seq, Chip-seq and CUT-RUN assays. RESULTS: Pt-ttpy, shows a highest accumulation in the mitochondria of A2780 cancer cells as compared with two other platinum(II) complexes with no/weak G4-binding properties, Pt-tpy and cisplatin. Pt-ttpy induces mtDNA deletion, copy reduction and transcription inhibition, hindering mt protein translation. Functional analysis reveals potent mt dysfunction without reactive oxygen species (ROS) induction. Mechanistic study provided first evidence that most of mt ribosome genes are highly enriched in G4 structures in their promoter regions, notably, Pt-ttpy impairs most nuclear-encoded mt ribosome genes' transcription through dampening the recruiting of transcription initiation and elongation factors of NELFB and TAF1 to their promoter with G4-enriched sequences. In vivo studies show Pt-ttpy's efficient anti-tumor effects, disrupting mt genome function with fewer side effects than cisplatin. CONCLUSION: This study underscores Pt-ttpy as a G4-binding platinum(II) complex, effectively targeting cancer mitochondria through dual action on mt and nuclear G4-enriched genomes without inducing ROS, offering promise for safer and effective platinum-based G4-targeted cancer therapy.

Low exposition to lithium prevents nephrogenic diabetes insipidus but not microcystic dilations of the collecting ducts in long-term rat model.

Lithium induces nephrogenic diabetes insipidus (NDI) and microcystic chronic kidney disease (CKD). As previous clinical studies suggest that NDI is dose-dependent and CKD is time-dependent, we investigated the effect of low exposition to lithium in a long-term experimental rat model. Rats were fed with a normal diet (control group), with the addition of lithium (Li+ group), or with lithium and amiloride (Li+/Ami group) for 6 months, allowing obtaining low plasma lithium concentrations (0.25 ± 0.06 and 0.43 ± 0.16 mmol/L, respectively). Exposition to low concentrations of plasma lithium levels prevented NDI but not microcystic dilations of kidney tubules, which were identified as collecting ducts (CDs) on immunofluorescent staining. Both hypertrophy, characterized by an increase in the ratio of nuclei per tubular area, and microcystic dilations were observed. The ratio between principal cells and intercalated cells was higher in microcystic than in hypertrophied tubules. There was no correlation between AQP2 messenger RNA levels and cellular remodeling of the CD. Additional amiloride treatment in the Li+/Ami group did not allow consistent morphometric and cellular composition changes compared to the Li+ group. Low exposition to lithium prevented overt NDI but not microcystic dilations of the CD, with differential cellular composition in hypertrophied and microcystic CDs, suggesting different underlying cellular mechanisms.

Scurvy complicated with Capnocytophaga sputigena sepsis as a possible cause of death of king Saint-Louis of France (1270 AD).

The cause of death of Saint-Louis is not known, but recent findings indicated that he presented scurvy and inflammatory jaw disease, which has been associated with infection by oral commensals. Here, we have the exceptional opportunity to analyze the relics of the viscera of King Saint-Louis. A 4.3 g sample from the viscera relics of King Saint-Louis conserved in Versailles' cathedral was subjected to radiocarbon dating, electronic and optic microscopy, and elementary, palynological, molecular, proteomics and microbiological analyses including specific PCR and v3v4 16 S rRNA gene amplification prior to large-scale sequencing using an Illumina MiSeq instrument. The measured radiocarbon age was Cal 1290 CE-1400, which was compatible with that of the viscera of St Louis viscera, considering the addition of lime, incense and vegetables within the human organs. Elemental and palynological analyses confirmed a medieval embalming process. Proteomics analysis identified mainly human muscle and blood proteins. Specific PCR for plague, amoebiasis, shigellosis and typhoid fever was negative. C. sputigena was identified as the main pathogenic species representing 10.8 % of all microbial sequences. In contrast, C. sputigena was found in only 0.001 % of samples sequenced in our center, and the 23 positive human samples showed a dramatically lower abundance (0.02-2.6 %). In the literature, human infections with C. sputigena included odontitis, dental abscess, sinusitis, thoracic infections and bacteremia, particularly in immunocompromised patients with oral and dental diseases consistent with recent analysis of King Saint-Louis' jaw. C. sputigena, a commensal of the mouth that is potentially pathogenic and responsible for fatal bacteremia, may have been the cause of the king's death.

Parenteral Zinc Intake in Newborns With Jejunostomy or Ileostomy: Results of a Monocentric Cohort Study.

OBJECTIVES: The aim of the study was to assess zinc status of newborns with parenteral nutrition with or without a small bowel stoma, to determine the incidence of zinc deficit, and to determine the clinical factors associated with plasma zinc levels. METHODS: Monocentric cohort study including all liveborn infants receiving zinc parenteral intake at 500 µg ·â€Škg ·â€Šday and who benefited from at least 1 plasma zinc assessment during hospitalization. RESULTS: Sixty-eight dosages of zinc were performed in 50 newborns, divided into 3 groups (no stoma = 26, jejunostomy = 11, ileostomy = 13). Thirty-seven of the 50 infants were born preterm. The mean ± standard deviation plasma zinc was 14.9 ±â€Š4.3 µmol/L and was similar among the 3 groups. Sixty-four percent, 3%, and 34% of zinc values were within, below, and above the normal range, respectively. In infants with jejunostomy, only 1 plasma zinc value (5%) was below the reference range. Plasma zinc levels were negatively correlated with stoma output (r = -0.449; P = 0.013). In contrast to patients with limited intestinal losses (ie, no stoma and ileostomy groups) no association between zinc levels and postmenstrual age was observed in infants with a jejunostomy suggesting that 500 µg ·â€Škg ·â€Šday was adequate not only in preterm infants but also in term infants with a jejunostomy. CONCLUSION: Plasma zinc levels decrease significantly with the increase of stoma output volume of newborns with small bowel stoma. Zinc deficit was prevented in newborns with a small bowel stoma receiving of 500 µg ·â€Škg ·â€Šday of parenteral zinc.

Sodium Transporters Are Involved in Lithium Influx in Brain Endothelial Cells.

Variability in drug response to lithium (Li+) is poorly understood and significant, as only 40% of patients with bipolar disorder highly respond to Li+. Li+ can be transported by sodium (Na+) transporters in kidney tubules or red blood cells, but its transport has not been investigated at the blood-brain barrier (BBB). Inhibition and/or transcriptomic strategies for Na+ transporters such as NHE (SLC9), NBC (SLC4), and NKCC (SLC12) were used to assess their role on Li+ transport in human brain endothelial cells. Na+-free buffer was also used to examine Na+/Li+ countertransport (NLCT) activity. The BBB permeability of Li+ evaluated in the rat was 2% that of diazepam, a high passive diffusion lipophilic compound. Gene expression of several Na+ transporters was determined in hCMEC/D3 cells, human hematopoietic stem-cell-derived BBB models (HBLEC), and human primary brain microvascular endothelial cells (hPBMECs) and showed the following rank order with close expression profile: NHE1 > NKCC1 > NHE5 > NBCn1, while NHE2-4, NBCn2, and NBCe1-2 were barely detected. Li+ influx in hCMEC/D3 cells was increased in Na+-free buffer by 3.3-fold, while depletion of chloride or bicarbonate had no effect. DMA (NHE inhibitor), DIDS (anionic carriers inhibitor), and bumetanide (NKCC inhibitor) decreased Li+ uptake significantly in hCMEC/D3 by 52, 51, and 47%, respectively, while S0859 (NBC inhibitor) increased Li+ influx 2.3-fold. Zoniporide (NHE1 inhibitor) and siRNA against NHE1 had no effect on Li+ influx in hCMEC/D3 cells. Our study shows that NHE1 and/or NHE5, NBCn1, and NKCC1 may play a significant role in the transport of Li+ through the plasma membrane of brain endothelial cells.

Outcomes after revision of metal on metal hip resurfacing to total arthroplasty using the direct anterior approach.

BACKGROUND: Function after revision total hip arthroplasty (THA) in failed metal-on-metal (MoM) hip resurfacing arthroplasty (HRA) is variable, but post-operative complication rates are reportedly high. We hypothesized HRA conversion to THA using the direct anterior approach (DAA) would be associated with optimal outcome. METHODS: Seventeen MoM-HRAs in 15 patients (seven males, eight females) were revised through the DAA. The mean age was 45 years (28-59 yrs). The most common indications for revision were aseptic loosening of the acetabular component or of the femoral component and femoral neck fracture. In 16 hips, a conversion to a ceramic-on-ceramic (CoC) (13 hips) or to a metal-on polyethylene (MOP) (2), or to a large-head MoM (1) THA was done. An isolated femoral revision was done in one hip. RESULTS: After 6.7 ± 3 years, no hip had required a re-revision. The Postel-Merle d'Aubigne (PMA) functional score improved from 9 (4-14) to 16 (12-18) (p < 0.001). An intra-operative fracture of the greater trochanter (one hip) and dysesthesia of the lateral femoral cutaneous nerve (four hips) were reported. Mean serum chromium concentration decreased from 33.2 µg/L (11.8-62 µg/L) pre-operatively to 5.8 µg/L (0.4-35.5 µg/L) post-operatively (p < 0.001), and mean serum cobalt concentration decreased from 35.8 µg/L (6.3-85.5 µg/L) to 4.7 µg/L (0.26-25.7 µg/L) (p = 0.003). CONCLUSION: Revision of failed MoM-HRA using the DAA resulted in an acceptable clinical outcome, no specific complication and no further surgery. A consistent decline in serum ion levels may be expected following HRA conversion to THA.

Platinum Complexes Can Bind to Telomeres by Coordination.

It is suggested that several compounds, including G-quadruplex ligands, can target telomeres, inducing their uncapping and, ultimately, cell death. However, it has never been demonstrated whether such ligands can bind directly and quantitatively to telomeres. Here, we employed the property of platinum and platinum-G-quadruplex complexes to target G-rich sequences to investigate and quantify their covalent binding to telomeres. Using inductively coupled plasma mass spectrometry, surprisingly, we found that, in cellulo, in the presence of cisplatin, a di-functional platinum complex, telomeric DNA was platinated 13-times less than genomic DNA in cellulo, as compared to in vitro data. On the contrary, the amount of mono-functional platinum complexes (Pt-ttpy and Pt-tpy) bound either to telomeric or to genomic DNA was similar and occurred in a G-quadruplex independent-manner. Importantly, the quantification revealed that the low level of cisplatin bound to telomeric DNA could not be the direct physical cause of TRF2 displacement from telomeres. Altogether, our data suggest that platinum complexes can affect telomeres both directly and indirectly.

Investigation of lithium distribution in the rat brain ex vivo using lithium-7 magnetic resonance spectroscopy and imaging at 17.2 T.

Lithium is the first-line mood stabilizer for the treatment of patients with bipolar disorder. However, its mechanisms of action and transport across the blood-brain barrier remain poorly understood. The contribution of lithium-7 magnetic resonance imaging (7 Li MRI) to investigate brain lithium distribution remains limited because of the modest sensitivity of the lithium nucleus and the expected low brain concentrations in humans and animal models. Therefore, we decided to image lithium distribution in the rat brain ex vivo using a turbo-spin-echo imaging sequence at 17.2 T. The estimation of lithium concentrations was performed using a phantom replacement approach accounting for B1 inhomogeneities and differential T1 and T2 weighting. Our MRI-derived lithium concentrations were validated by comparison with inductively coupled plasma-mass spectrometry (ICP-MS) measurements ([Li]MRI  = 1.18[Li]MS , R = 0.95). Overall, a sensitivity of 0.03 mmol/L was achieved for a spatial resolution of 16 µL. Lithium distribution was uneven throughout the brain (normalized lithium content ranged from 0.4 to 1.4) and was mostly symmetrical, with consistently lower concentrations in the metencephalon (cerebellum and brainstem) and higher concentrations in the cortex. Interestingly, low lithium concentrations were also observed close to the lateral ventricles. The average brain-to-plasma lithium ratio was 0.34 ± 0.04, ranging from 0.29 to 0.39. Brain lithium concentrations were reasonably correlated with plasma lithium concentrations, with Pearson correlation factors ranging from 0.63 to 0.90.

Association of a Platinum Complex to a G-Quadruplex Ligand Enhances Telomere Disruption.

Telomeres protect the ends of chromosomes against illegitimate recombination and repair. They can be targets for G-quadruplex ligands and platinum complexes due to their repeated G-rich sequences. Protection of telomeres is ensured by a complex of six proteins, including TRF2, which inhibits the DNA damage response pathway. We analyzed telomere modifications induced in cancer cells by the experimental hybrid platinum complex, Pt-MPQ, comprising both an ethylene diamine monofunctional platinum complex and a G-quadruplex recognition moiety (MPQ). Pt-MPQ promotes the displacement of two telomeric proteins (TRF2 and TRF1) from telomeres, as well as the formation of telomere damage and telomere sister losses, whereas the control compound MPQ does not. This suggests that the platinum moiety potentiates the targeting of the G-quadruplex ligand to telomeres, opening a new perspective for telomere biology and anticancer therapy. Interestingly, the chemotherapy drug cisplatin, which has no specific affinity for G-quadruplex structures, partially induces the TRF2 delocalization from telomeres but produces less telomeric DNA damage, suggesting that this TRF2 displacement could be independent of G-quadruplex recognition.

Electroencephalographic patterns of lithium poisoning: a study of the effect/concentration relationships in the rat.

OBJECTIVES: Lithium overdose may result in encephalopathy and electroencephalographic abnormalities. Three poisoning patterns have been identified based on the ingested dose, previous treatment duration and renal function. Whether the severity of lithium-induced encephalopathy depends on the poisoning pattern has not been established. We designed a rat study to investigate lithium-induced encephalopathy and correlate its severity to plasma, erythrocyte, cerebrospinal fluid and brain lithium concentrations previously determined in rat models mimicking human poisoning patterns. METHODS: Lithium-induced encephalopathy was assessed and scored using continuous electroencephalography. RESULTS: We demonstrated that lithium overdose was consistently responsible for encephalopathy, the severity of which depended on the poisoning pattern. Acutely poisoned rats developed rapid-onset encephalopathy which reached a maximal grade of 2/5 at 6 h and disappeared at 24 h post-injection. Acute-on-chronically poisoned rats developed persistent and slightly fluctuating encephalopathy which reached a maximal grade of 3/5. Chronically poisoned rats developed rapid-onset but gradually increasing life-threatening encephalopathy which reached a maximal grade of 4/5. None of the acutely, 20% of the acute-on-chronically and 57% of the chronically lithium-poisoned rats developed seizures. The relationships between encephalopathy severity and lithium concentrations fitted a sigmoidal Emax model based on cerebrospinal fluid concentrations in acute poisoning and brain concentrations in acute-on-chronic poisoning. In chronic poisoning, worsening of encephalopathy paralleled the increase in plasma lithium concentrations. CONCLUSIONS: The severity of lithium-induced encephalopathy is dependent on the poisoning pattern, which was previously shown to determine lithium accumulation in the brain. Our data support the proposition that electroencephalography is a sensitive tool for scoring lithium-related neurotoxicity.

Linking of Antitumor trans NHC-Pt(II) Complexes to G-Quadruplex DNA Ligand for Telomeric Targeting.

G-quadruplex structures (G4) are promising anticancerous targets. A great number of small molecules targeting these structures have already been identified through biophysical methods. In cellulo, some of them are able to target either telomeric DNA and/or some sequences involved in oncogene promotors, both resulting in cancer cell death. However, only a few of them are able to bind to these structures G4 irreversibly. Here we combine within the same molecule the G4-binding agent PDC (pyridodicarboxamide) with a N-heterocyclic carbene-platinum complex NHC-Pt already identified for its antitumor properties. The resulting conjugate platinum complex NHC-Pt-PDC stabilizes strongly G-quadruplex structures in vitro, with affinity slightly affected as compared to PDC. In addition, we show that the new conjugate binds preferentially and irreversibly the quadruplex form of the human telomeric sequence with a profile in a way different from that of NHC-Pt thereby indicating that the platination reaction is oriented by stacking of the PDC moiety onto the G4-structure. In cellulo, NHC-Pt-PDC induces a significant loss of TRF2 from telomeres that is considerably more important than the effect of its two components alone, PDC and NHC-Pt, respectively.

[Not Available]. / Les produits d'embaumement égyptiens : nouvelles données pharmacologiques.

Today, the development of analytic methods brings new scientific insights into the research on the mummification process used by embalmers in ancient Egypt. The application of these techniques of molecular analysis, elementary analysis, botanical analysis and bibliographic analysis of ancient texts allows us to know the composition of mummification balms and material involved in the conservation of the body. Such substances, which are mineral, animal or plant material, played a practical and a symbolic part in the composition of balms used for the preservation of mummified bodies and therefore in the passage to the eternal life after the death. The comparison of analysis results can inform us about changes in embalming techniques depending of the time, the place of mummification, the deceased's social status. However the number of mummies studied is very small compared to the number of bodies that were mummified. Finally the techniques of mummification and making balms were very variable according to practitioners and their modus operandi. Today, using these technic of chemical analysis and medical imaging techniques, we can authenticate and reconstruct the history of museum pieces, as we have done in the unpublished studies conducted in support of literature data previously collected.

Relative exchangeable copper: a promising tool for family screening in Wilson disease.

BACKGROUND: Family screening is a main step for the diagnosis in Wilson disease. This study was undertaken to evaluate the value of relative exchangeable copper for family screening. METHODS: Data from family screening were collected from the French National Center of Reference for Wilson disease. Subjects who were first- or second-degree relatives of the index case underwent clinical examination and biological parameters. RESULTS: Of 127 subjects examined, copper abnormalities or low ceruloplasminemia were detected in 21 subjects, corresponding to 5 patients with Wilson disease, 14 heterozygous ATP7B carriers and 2 subjects with no ATP7B mutations. Relative exchangeable copper determination significantly discriminates heterozygous ATP7B carriers and subjects with no ATP7B mutations from WD patients with a cutoff of 15%. CONCLUSIONS: Exchangeable copper appears to be a promising tool for family screening in Wilson disease.

The rotavirus nonstructural protein NSP5 coordinates a [2Fe-2S] iron-sulfur cluster that modulates interaction to RNA.

During rotavirus infection, replication and packaging of the viral genome occur in viral factories, termed viroplasms. The viral nonstructural protein NSP5 is a major building block of viroplasms; it recruits the viral polymerase VP1, the core protein VP2, and the ATPase NSP2 inside the viroplasm to form the viral replication complex. Here we report that NSP5 is a unique viral metalloprotein that coordinates a [2Fe-2S] iron-sulfur cluster as demonstrated by the metal and labile sulfide contents, UV-visible light absorption, and electron paramagnetic resonance. Point mutations in NSP5 allowed us to identify C171 and C174, arranged in a CXC motif, as essential residues for cluster coordination. When coexpressed with NSP2, an NSP5 mutant devoid of the iron-sulfur cluster still forms viroplasm-like structures. The cluster is therefore neither involved in the interaction with NSP2 nor in the formation of viroplasm-like structures and thus presumably in viroplasm formation. Finally, we show using microscale thermophoresis that the iron-sulfur cluster modulates the affinity of NSP5 for single-stranded RNA. Because the cluster is near the binding sites of both the polymerase VP1 and the ATPase NSP2, we anticipate that this cluster is crucial for NSP5 functions, in either packaging or replication of the viral genome.

Efficacy of oral manganese and D-galactose therapy in a patient bearing a novel TMEM165 variant.

TMEM165-CDG has first been reported in 2012 and manganese supplementation was shown highly efficient in rescuing glycosylation in isogenic KO cells. The unreported homozygous missense c.928G>C; p.Ala310Pro variant leading to a functional but unstable protein was identified. This patient was diagnosed at 2 months and displays a predominant bone phenotype and combined defects in N-, O- and GAG glycosylation. We administered for the first time a combined D-Gal and Mn2+ therapy to the patient. This fully suppressed the N-; O- and GAG hypoglycosylation. There was also striking improvement in biochemical parameters and in gastrointestinal symptoms. This study offers exciting therapeutic perspectives for TMEM165-CDG.

Anti-Cancer and Radio-Sensitizing Properties of New Bimetallic (N-Heterocyclic Carbene)-Amine-Pt(II) Complexes.

Bioactive NHC-transition metal complexes have shown promise as anti-cancer agents, but their potential use as radiosensitizers has been neglected so far. We disclose here a new series of bimetallic platinum(II) complexes displaying NHC-type bridging ligands, (bis-NHC)[trans-Pt(RNH2)I2]2, that have been synthesized via a simple, two-step procedure. They display cytotoxicity in the micromolar range on cancerous cell lines, accumulate in cells, and bind to genomic DNA, by inducing DNA damages. Notably, these bimetallic complexes demonstrate significant radiosensitizing effects on both ovarian cells A2780 and nonsmall lung carcinoma cells H1299. Further investigations revealed that bimetallic species make irradiation-induced DNA damages more persistent by inhibiting repair mechanisms. Indeed, a higher and persistent accumulation of both γ-H2AX and 53BP1 foci post-irradiation was detected, in the presence of the NHC-Pt complexes. Overall, we provide the first in vitro evidence for the radiosensitizing properties of NHC-platinum complexes, which suggests their potential use in combined chemo-radio therapy protocols.

Importance des réseaux sociaux dans l'origine des intoxications : à propos d'un cas d'empoisonnement par la paraphénylènediamine.

Une femme de 63 ans rapporte avoir acheté une « pierre noire ¼ pour se protéger de la Covid-19 à la suite de conseils trouvés sur des réseaux sociaux. Dans les 24 heures qui suivent l'absorption d'une cuillère à soupe d'un mélange de « pierre ¼ avec du miel, apparaissent des myalgies puis une altération de l'état général qui la conduit à consulter aux urgences après 5 jours. L'examen clinique est sans autre particularité alors que le bilan biologique rapporte une insuffisance rénale aiguë et une rhabdomyolyse. L'évolution est marquée par une aggravation de l'insuffisance rénale nécessitant plusieurs séances d'hémodialyse. Les circonstances d'apparition des symptômes associées à la consommation de la « pierre ¼ font suspecter une origine toxique. Un tube de sang et la « pierre ¼ sont adressés au Laboratoire de toxicologie biologique pour analyses. La « pierre ¼ friable, noire en surface, blanche en interne, est soluble dans les alcools et peu soluble dans l'eau. L'analyse par plasma à couplage inductif - spectrométrie de masse - ne retrouve ni éléments métalliques, ni métalloïdes. L'analyse par chromatographie gazeuse couplée à la spectrométrie de masse met en évidence un pic identifié comme de la paraphénylènediamine (PPD). Une analyse par spectroscopie UV permet d'estimer la pureté de la « pierre ¼ à plus de 99 %. La PPD utilisée comme teinture capillaire noire ou adjuvant du henné est responsable d'intoxications graves, majoritairement volontaires, caractérisées par une détresse respiratoire, une rhabdomyolyse associée à des douleurs musculaires et à une insuffisance rénale. À l'exception de la détresse respiratoire, notre patiente a présenté tous les signes cliniques de l'intoxication. L'absence de détection de la PPD dans le plasma s'explique tant par la mise en œuvre de méthodes non adaptées à la détection de ce type de composés chimiques, que par le délai écoulé depuis la consommation de la « pierre ¼.

High Response Rate and Corticosteroid Sparing with Arsenic Trioxide-Based First-Line Therapy in Chronic Graft-versus-Host Disease after Allogeneic Hematopoietic Stem Cell Transplantation.

Chronic graft-versus-host disease (cGVHD) occurs in 20% to 50% of recipients after allogeneic hematopoietic stem cell transplantation (allo-HSCT). Corticosteroids (CS) remain the first-line therapy but have suboptimal efficacy and carry a risk of long-term side effects. New agents with a better safety profile and higher efficacy are urgently needed. This study aimed to evaluate the efficacy and safety of a first-line combination of arsenic trioxide (ATO) and CS in adult patients with cGVHD requiring systemic therapy after first allo-HSCT for a hematologic disease. In this prospective national multicenter single-arm open-label Phase II study conducted in 5 university hospital centers in France, ATO was started within 10 days of CS at 1 mg/kg/day. Patients received 11 infusions per cycle of 28 days at a dose of .15 mg/kg per infusion. According to the clinical response and depending on the clinician's opinion, patients received 1 or 2 cycles of treatment. Cycles were separated by an 8- to 11-week interval from the first infusion of ATO. Patients were evaluated at 6 weeks, 14 weeks, 6 months, 9 months, and 12 months after the first ATO infusion, using the Chronic GVHD Activity Assessment Form A. The primary endpoint was preliminary efficacy based on the overall response rate (ORR; complete response [CR] or partial response [PR]) at 6 months. Response rates were estimated with 2-sided 95% exact confidence intervals (CIs). Twenty-one patients entered the study and received at least 1 ATO infusion (1 incomplete cycle for 1 patient, 1 complete cycle for 11 patients, and 2 complete cycles for 9). Six patients continued ongoing cyclosporine A (CsA) treatment after inclusion, and 4 other patients resumed CsA treatment during the study. The ORR at 6 months was 75.0% (95% CI, 50.9% to 91.3%), with CR in 35% and PR in 40%. Failure-free survival was 90.0% (95% CI, 65.6% to 97.4%) at 6 months and 65.0% (95% CI, 40.3% to 81.5%) at 12 months. The progression-free survival rate was 95.0% (95% CI, 69.5% to 99.3%) at 6 months and 83.8% (95% CI, 57.7% to 94.5%) at 12 months. The mean CS dose was decreased by 74.6 ± 32.7% from baseline to the 6-month visit and by 91.0 ± 14.6% from baseline to the 12-month visit. CS was definitively stopped in 30.0% of patients at the 6-month visit and in 47.4% at the 12-month visit. Two patients died, at 7 months and 12 months after the first ATO infusion from causes unrelated to ATO. One patient withdrew because of transient hepatotoxicity. The first-line combination of ATO and CS was associated with a high clinical response rate and rapid CS sparing in cGVHD after previous allo-HSCT.