STAT3 Mutations Research Articles

Distinct mutational pattern of T-cell large granular lymphocyte leukemia combined with pure red cell aplasia: low mutational burden of STAT3

T-cell large granular lymphocyte leukemia (T-LGL) is often accompanied by pure red cell aplasia (PRCA). A high depth of next generation sequencing (NGS) was used for detection of the mutational profiles in T-LGL alone (n = 25) and T-LGL combined with PRCA (n = 16). Beside STAT3 mutation (41.5%), the frequently mutated genes included KMT2D (17.1%), TERT (12.2%), SUZ12 (9.8%), BCOR (7.3%), DNMT3A (7.3%), and RUNX1 (7.3%). Mutations of the TERT promoter showed a good response to treatment. 3 of 41 (7.3%) T-LGL patients with diverse gene mutations were revealed as T-LGL combined with myelodysplastic syndrome (MDS) after review of bone marrow slide. T-LGL combined with PRCA showed unique features (low VAF level of STAT3 mutation, low lymphocyte count, old age). Low ANC was detected in a STAT3 mutant with a low level of VAF, suggesting that even the low mutational burden of STAT3 is sufficient for reduction of ANC. In retrospective analysis of 591 patients without T-LGL, one MDS patient with STAT3 mutation was revealed to have subclinical T-LGL. T-LGL combined with PRCA may be classified as unique subtype of T-LGL. High depth NGS can enable sensitive detection of concomitant MDS in T-LGL. Mutation of the TERT promoter may indicate good response to treatment of T-LGL, thus, its addition to an NGS panel may be recommended.

HSV-1 and HHV-6 Meningoencephalitis in a Child with STAT1 Mutation

Introduction: STAT1 is a critical signal transducer for both the interferon gamma receptor and IFN-alpha/beta receptors and is required for responses to herpesviruses. STAT1 defects vary in severity and clinical presentation. STAT1 loss of function (LOF) mutations with Mendelian Susceptibility to Mycobacterial Disease (MSMD) and STAT1 gain of function (GOF) mutations have been described with a wide clinical spectrum, including nontuberculous mycobacteria, disseminated fungal, bacterial, and viral infections in addition to immune dysregulation. We present a 10-year-old female with HSV-1 and HHV-6 meningoencephalitis that was found to have a variant in STAT1. MethodsRetrospective chart review was conducted. Laboratory investigations included lymphocyte immunophenotyping by flow cytometry, lymphocyte proliferation to mitogens and antigens, NK cell functional assays, quantitative immunoglobulins, toll like receptor function defects, genetic evaluation by next generation sequencing, and assays for further evaluation for MSMD, T helper IL17, STAT GOF. ResultsA previously healthy 10-year-old Caucasian female presented with fever, headache, and new-onset seizure with status epilepticus. She was diagnosed with HSV-1 and HHV-6 meningoencephalitis, as CSF PCR panel was positive for HSV-1 and HHV-6. Brain MRI showed findings compatible with HSV-1 encephalitis. She was treated with a 14-day course of acyclovir with no noted neurological sequelae. Infection history was unremarkable except for one episode of otitis media as a child and a couple upper respiratory viral illnesses. Denied prior history of HSV infection. No family history of immunodeficiency disorders. Both parents reported remote history of herpetic gingivostomatitis. Laboratory immune evaluation was remarkable for decreased lymphocyte proliferative response to Candida antigen. Next generation sequencing revealed a variant of uncertain significance in STAT1 (c.295A>G; p.Ile99Val) and did not detect TLR3 or UNC93B1 mutations. ConclusionThe clinical phenotype caused by STAT1 mutations is highly diverse, and there is overlap between GOF and LOF phenotypes, making it difficult to clinically diagnose. Although HSV gingivostomatitis has been reported in a patient with STAT1 GOF, invasive disease, such as meningoencephalitis, has not been reported in those with variants in STAT1.

Combined Hepatocellular-Cholangiocarcinoma With Ductal Plate Malformation Pattern: A Case Report With Molecular Analysis.

Combined hepatocellular-cholangiocarcinoma with a ductal plate malformation pattern is an extremely rare entity with unelucidated pathogenesis. We present the case of a 60-year-old male patient who underwent a sectionectomy for pre-operative diagnosis of hepatocellular carcinoma based on clinical and image findings. Gross examination of the specimen revealed a well-defined tumor with cystic change measuring 6.7 × 6.2 cm. Microscopically, the lesion had classical features of hepatocellular carcinoma and intrahepatic cholangiocarcinoma exhibited neoplastic glands with irregular-sized dilated lumens, resembling a ductal plate malformation. Postoperative diagnosis was combined hepatocellular-cholangiocarcinoma with ductal plate malformation pattern. Next-generation sequencing revealed genomic alteration in 15 genes: CDKN2A, CHD4, CYP2D6, ERBB3, KIR3DL1, KRAS, MDM2, PIM1, STAT6, TPMT amplification, FANCD2, FAT1, FLT4, RASA1, and TP53 point mutation. This is the first case report of molecular alteration in combined hepatocellular-cholangiocarcinoma with ductal plate malformation pattern.

Impact of Early Intervention for STAT3 Dominant-Negative Disease

IntroductionSTAT3 dominant negative disease (STAT3 DN) is characterized by elevated IgE, recurrent skin and lung infections, skeletal, connective tissue, and vascular abnormalities. Early genetic diagnosis, especially with familial disease, allows for early intervention, which may impact natural history through minimizing infectious complications. MethodsWe retrospectively reviewed medical records of 18 STAT3 DN pediatric patients born after 2007, when STAT3 genetic testing was available. Clinical features, laboratory results, infections and treatments were compared between those with STAT3 DN family history and probands. ResultsOur cohort included 8 patients with STAT3 DN diagnosed by family history (median age 9 years; range 4–14) and 10 probands (median age 13 years, range 5–14). For those with family history, one was diagnosed in utero, six by 6 months of age, and one at 2 years. Probands were diagnosed at a median age of 2 years (range 1–6 years). STAT3 mutation domains were similar between groups. Those with family history started antiseptic washes at a mean of 2.4 months and prophylactic antibiotics at 0.4 years, whereas probands initiated antiseptics at 4.5 years and prophylactic antibiotics at 3 years. Compared to probands, patients with STAT3 DN diagnosed by family history had significantly (p < 0.05) reduced rates of hospitalizations (mean 0.6 vs 6.2 times), bacterial pneumonias (13% vs 90%), >4 skin abscesses (25% vs 90%), other serious infections (0% vs 40%), recurrent ear infections and/or tympanostomy tube placement (0% vs 60%), and severe eczema (13% vs 60%). Significant differences were not seen in parenchymal lung abnormalities (13% vs 50%, p = 0.09) and non-immunologic features, such as fractures and joint hyperextensibility. Mean peak serum IgE and absolute eosinophil counts (AEC) were comparable (IgE 6,865 vs 13,317 IU/mL; AEC 1,023 vs 1,182 cells/uL in family history vs probands). Those with family history received less advanced therapies than probands, specifically immunoglobulin replacement (13% vs 60%), antifungals (25% vs 60%), and lung surgery (0% vs 40%). One proband received bone marrow transplantation. ConclusionEarly diagnosis and intervention positively impacts disease course and management with markedly reduced rates of infectious complications, which may decrease future morbidity and mortality in this vulnerable patient population.

TBX1 copy number variant of unknown significance presenting as severe esophageal stricture and recurrent candidiasis

IntroductionTBX1 Is involved in pharyngeal pouch development affecting thymus, parathyroid, craniofacial, and cardiac outflow tract development. TBX1 deletions present with phenotype of Di George syndrome. We present the case of a patient with esophageal stricture and candidiasis showing a novel TBX1 gene triplication VUS. Case descriptionA 27-year-old male was hospitalized for hematemesis and progressive dysphagia. The physical exam was remarkable for short stature, underweight, dental hypoplasia, alopecia and occipital vitiligo. Calcium and lymphocyte numbers were normal. Severe esophageal strictures precluded upper endoscopy. He received IV fluconazole for two weeks to continue oral antifungal indefinitely. Since infancy he has had multiple candida infections in nails and oral mucosa requiring fluconazole, and medical history of asthma and atopic dermatitis. No history of cardiac abnormalities. At 14 years old he started with progressive dysphagia. Barium swallow and endoscopies showed severe acute and chronic esophagitis and thoracic esophageal strictures with severe stenosis. Patient's sister has history of candida infections, hypocalcemia due to hypoparathyroidism, and hypothyroidism. There is consanguinity among paternal grandparents. Invitae PID panel showed VUS with TBX1 gene triplication, not previously reported. Familial genetic testing was requested for her sister to support the diagnosis of DiGeorge Syndrome. DiscussionTBX1 gene deletions present a spectrum clinical phenotype including thymic hypoplasia, hypocalcemia, and congenital heart defects. TBX1 duplication and gain of function TBX1 heterozygous mutation led to protein dysfunction and a similar phenotype caused by loss-of-function mutations or deletions. TBX1 triplication could plausibly lead to dysfunctional protein expression, which requires confirmation. TBX1 is a negative regulator of thymic epithelial cell differentiation and proliferation, which could affect immune regulation and explain patient's chronic candida infections. Feeding difficulties and esophageal dysmotility have been reported in Di George syndrome. Sibling's hypocalcemia due to hypoparathyroidism could be explained by TBX1 dysfunction. APECED was considered in differential diagnosis due to chronic mucocutaneous candidiasis and sister's endocrinopathies, nevertheless, no AIRE or STAT1 mutations identified. Genetic analysis and familiar VUS have the potential to identify the cause of PIDs. TBX1 transcript and protein expression analysis will contribute to confirming the diagnostic impression.

Innate immune side of STAT1 GOF

STAT1 gain-of-function (GOF) mutations underlie an inborn error of immunity hallmarked by chronic mucocutaneous candidiasis (CMC). Beyond the fungal susceptibility, attributed to Th17 failure, over half of the reported patients suffer from autoimmune manifestations, which remain mechanistically unexplained. Surprisingly, little is known about the biological consequences of augmented STAT1 signaling in innate immune cells. Considering the importance of innate immune mechanisms in antifungal defense and autoimmune complications, we examined the phenotype and function of monocytes and dendritic cells in a cohort of patients with STAT1 GOF.We demonstrated that human ex vivo STAT1 GOF monocytes are characterized by proinflammatory phenotype and strong inflammatory skew of their secretory cytokine profile. The distribution of monocytes subpopulations’ is altered and they exhibit various functional abnormalities, which might represent a contributing mechanism in the pathogenesis of STAT1 GOF-associated autoimmunity, e.g., a selectively enhanced responsiveness to TLR7/8 stimulation, but not to other TLR ligands. Importantly, some of these features extend to STAT1 GOF myeloid dendritic cells, suggesting that the alterations observed in monocytes are, in fact, intrinsic due to STAT1 mutation, and not mere secondary consequence of the chronic inflammatory milieu.To follow up on the ex vivo data, we employed an in vitro model of monocyte-derived DC (moDC) and tolerogenic DC (tDC). Functional and signaling studies, co-culture experiments and RNA sequencing demonstrated that STAT1 GOF DCs were profoundly altered in their phenotype and functions, characterized by loss of tolerogenic functions, proinflammatory skew and decreased capacity to induce Th17. Cytokine signaling, autophagy and metabolic processes were identified as the most prominently altered cellular processes.In conclusion, we present first-ever data implying a direct involvement of monocytes and DCs in the STAT1 GOF-associated immune pathology, possibly contributing to both autoimmune manifestations and the failure of antifungal defense. Our work thus highlights a yet understudied innate immune background in STAT1 GOF which should be dissected in details by future research.

Application of circulating tumour DNA in terms of prognosis prediction in Chinese follicular lymphoma patients.

Background: Follicular lymphoma (FL), an indolent non-Hodgkin lymphoma (NHL), is generally incurable. Favourable prognosis and durable remission are crucial for FL patients. The genetic mutation spectrum provides novel biomarkers for determining the prognosis of FL patients, but its detection is easily affected by the collection of tumour tissue biopsies. In this study, we aimed to describe the mutational landscape of FL using circulating tumour DNA (ctDNA) samples and to explore the relationship between mutations and prognostic indicators of clinical outcome in patients with newly diagnosed follicular lymphoma and the prognostic value of such mutations. Methods: A total of 28 patients with newly diagnosed FL were included in this study. A targeted NGS-based 59-gene panel was used to assess the ctDNA mutation profiles. Differences in clinical factors between patients carrying mutations and those without mutations were analysed. We also explored the relationship between gene mutation status, mean VAFs (variant allele frequencies) and clinical factors. The Kaplan‒Meier method was applied to analyse the overall survival (OS) and progression-free survival (PFS) of patients carrying mutations and those without mutations. Results: ctDNA mutations were detectable in 21 (75%) patients. The most commonly mutated genes were CREBBP (54%, 15/28), KMT2D (50%, 14/28), STAT6 (29%, 8/28), CARD11 (18%, 5/28), PCLO (14%, 4/28), EP300 (14%, 4/28), BCL2 (11%, 3/28), and TNFAIP3 (11%, 3/28), with a mutation frequency of >10%. Patients with detectable ctDNA mutation tended to present with advanced Ann Arbor stage (III-IV) (p = 0.009), high FLIPI risk (3-5) (p = 0.023) and severe lymph node involvement (No. of involved areas ≥5) (p = 0.02). In addition, we found that the mean VAF was significantly higher in patients with advanced Ann Arbor stage, high-risk FLIPI, elevated lactate dehydrogenase (LDH: 0-248U/L), advanced pathology grade, bone marrow involvement (BMI) and lymph node involvement. Additionally, KMT2D, EP300, and STAT6 mutations were associated with inferior PFS (p < 0.05). Conclusion: We described the ctDNA mutation landscapes in Chinese patients with newly diagnosed FL and found that ctDNA VAF means reflect tumour burden. Moreover, PFS was shorter in patients with KMT2D, EP300 and STAT6 mutations.

Disseminated Talaromyces marneffei Infection With STAT3-Hyper-IgE Syndrome: A Case Series and Literature Review.

Little is known about the clinical characteristics of talaromycosis with hyper-immunoglobulin E syndrome (HIES). We conducted a multicenter retrospective study, which included 7 hospitals from 2016 to 2022. Five consecutive cases of human immunodeficiency virus (HIV)-negative patients with systemic Talaromyces marneffei infections due to STAT3-HIES were identified. A systematic literature review of original articles published in English identified an additional 7 cases. Clinical characteristics and laboratory parameters were collected. Forty-two percent (5/12) of patients were young adults. The main symptoms of 10 patients were similar: fever (75%), cough (75%) and dyspnea (33%), but two patients mainly had gastrointestinal symptoms. Most patients had a history of infections since infancy. T marneffei was cultured from the bronchoalveolar lavage fluid (50%) and 25% of patients were next-generation sequencing positive. Eight patients had significantly elevated serum immunoglobulin E, increased B cells and decreased natural killer cells. There were ten different STAT3 mutations, three of which were reported for the first time in this study. Chest computed tomography examinations showed multiple exudations with cavities in the lungs. Voriconazole combined with thymosin was effective. Despite given antifungal agents, most had poor outcomes and the case fatality rate was as high as 25%. STAT3-HIES is most likely a susceptibility factor for T marneffei infections among HIV-negative patients, which has a high case fatality rate. Increased awareness among clinicians is necessary to help in early diagnosis.

Abstract 3738: A novel mechanism of STAT3 activation by genotoxic chemotherapy

Abstract CARP-1, a perinuclear phospho-protein, is a biphasic regulator of cell survival and apoptosis signaling induced by genotoxic drugs. We have previously found that apoptosis induced by genotoxic drugs involved elevated levels of CARP-1. Exposure to genotoxic drugs also induced CARP-1 interaction with NF-κB kinase subunit γ (aka, NEMO) to promote NF-κB activation and cell survival. To further elucidate chemotherapy-activated, CARP-1-dependent cell survival mechanisms, we UV cross-linked protein extracts from Adriamycin-treated HeLa cervical cancer cells with a CARP-1 (614-638) peptide, and conducted liquid chromatography-tandem mass spectrometry (LC-MS/MS) analyses of the peptide-bound protein complexes. This experiment revealed STAT3 interaction with CARP-1 (614-638) peptide. Our mutagenesis and co-IP-WB experiments revealed CARP-1 (550-650) directly interacts with a 40 amino acid peptide located in the STAT3 DNA binding domain. Overexpression of mutant STAT3 with in-frame-deletion of CARP-1/CCAR1-binding epitope (CE) peptide (Gst-STAT3 (ΔCE) mutant), but not Gst-STAT3 (WT), failed to translocate to nucleus in Adriamycin-treated cells. Disruption of STAT3-CARP-1 interaction or expression of STAT3 (ΔCE) mutant abolished Adriamycin-induced STAT3 Y705 and S727 phosphorylation. Collectively our data demonstrate that CARP-1 interaction with STAT3 regulates genotoxic chemotherapy-activated STAT3 and its nuclear translocation to promote cancer cell survival and growth. Citation Format: Jaganathan Venkatesh, Magesh Muthu, Nuwan C. Acharige, Mary K. Pflum, Arun K. Rishi. A novel mechanism of STAT3 activation by genotoxic chemotherapy. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 3738.

Highlighted research articles

In This Issue| April 03 2023 Highlighted research articles Author & Article Information Online ISSN: 2159-8290 Print ISSN: 2159-8274 ©2023 American Association for Cancer Research2023American Association for Cancer Research Cancer Discov (2023) 13 (4): 799–800. https://doi.org/10.1158/2159-8290.CD-13-4-ITI Related Content This is a related article to: Dynamics of Age- versus Therapy-Related Clonal Hematopoiesis in Long-term Survivors of Pediatric Cancer This is a related article to: Intratumoral Heterogeneity and Clonal Evolution Induced by HPV Integration This is a related article to: Antibody–Exatecan Conjugates with a Novel Self-immolative Moiety Overcome Resistance in Colon and Lung Cancer View more This is a related article to: Blocking Genomic Instability Prevents Acquired Resistance to MAPK Inhibitor Therapy in Melanoma This is a related article to: Genomic Instability and Protumoral Inflammation Are Associated with Primary Resistance to Anti–PD-1 + Antiangiogenesis in Malignant Pleural Mesothelioma This is a related article to: LKB1-Dependent Regulation of TPI1 Creates a Divergent Metabolic Liability between Human and Mouse Lung Adenocarcinoma This is a related article to: Extrachromosomal DNA Amplification Contributes to Small Cell Lung Cancer Heterogeneity and Is Associated with Worse Outcomes This is a related article to: Targeting Microglial Metabolic Rewiring Synergizes with Immune-Checkpoint Blockade Therapy for Glioblastoma View less Views Icon Views Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Cite Icon Cite Search Site Article Versions Icon Versions Version of Record April 3 2023 Citation Highlighted research articles. Cancer Discov 1 April 2023; 13 (4): 799–800. https://doi.org/10.1158/2159-8290.CD-13-4-ITI Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest Search Advanced Search Pediatric cancer survivors are at risk of accelerated physiologic aging. Hagiwara and colleagues profiled 2,860 long-term survivors by deep sequencing and detected clonal hematopoiesis (CH) in 15% of survivors, which is significantly higher than in community controls (8.5%). CH in survivors is associated with exposures to alkylating agents, radiation, and bleomycin and is significantly enriched in TP53 and STAT3. Mutations in STAT3, characterized as a CH gene specific to Hodgkin lymphoma survivors, occur predominantly in T cells and are contributed by SBS25, a mutational signature associated with procarbazine exposure. Longitudinal monitoring is recommended to ascertain the long-term effects of CH in pediatric cancer survivors. See article, p. 844. Antiangiogenics potentiate immune checkpoint blockade efficacy in advanced mesotheliomas, but a majority of patients present primary resistance to this combination. Danlos and colleagues analyzed sequential fixed, frozen, and fresh blood and tumor samples from patients with mesothelioma treated with pembrolizumab... You do not currently have access to this content.

Regulation of microglia related neuroinflammation contributes to the protective effect of Gelsevirine on ischemic stroke.

Stroke, especially ischemic stroke, is an important cause of neurological morbidity and mortality worldwide. Growing evidence suggests that the immune system plays an intricate function in the pathophysiology of stroke. Gelsevirine (Gs), an alkaloid from Gelsemium elegans, has been proven to decrease inflammation and neuralgia in osteoarthritis previously, but its role in stroke is unknown. In this study, the middle cerebral artery occlusion (MCAO) mice model was used to evaluate the protective effect of Gs on stroke, and the administration of Gs significantly improved infarct volume, Bederson score, neurobiological function, apoptosis of neurons, and inflammation state in vivo. According to the data in vivo and the conditioned medium (CM) stimulated model in vitro, the beneficial effect of Gs came from the downregulation of the over-activity of microglia, such as the generation of inflammatory factors, dysfunction of mitochondria, production of ROS and so on. By RNA-seq analysis and Western-blot analysis, the JAK-STAT signal pathway plays a critical role in the anti-inflammatory effect of Gs. According to the results of molecular docking, inhibition assay, and thermal shift assay, the binding of Gs on JAK2 inhibited the activity of JAK2 which inhibited the over-activity of JAK2 and downregulated the phosphorylation of STAT3. Over-expression of a gain-of-function STAT3 mutation (K392R) abolished the beneficial effects of Gs. So, the downregulation of JAK2-STAT3 signaling pathway by Gs contributed to its anti-inflammatory effect on microglia in stroke. Our study revealed that Gs was benefit to stroke treatment by decreasing neuroinflammation in stroke as a potential drug candidate regulating the JAK2-STAT3 signal pathway.

Severe allergic dysregulation due to a gain of function mutation in the transcription factor STAT6

Inborn errors of immunity have been implicated in causing immune dysregulation, including allergic diseases. STAT6 is a key regulator of allergic responses. This study sought to characterize a novel gain-of-function STAT6 mutation identified in a child with severe allergic manifestations. Whole-exome and targeted gene sequencing, lymphocyte characterization, and molecular and functional analyses of mutated STAT6 were performed. This study reports a child with a missense mutation in the DNA binding domain of STAT6 (c.1114G>A, p.E372K) who presented with severe atopic dermatitis, eosinophilia, and elevated IgE. Naive lymphocytes from the affected patient displayed increased TH2- and suppressed TH1- and TH17-cell responses. The mutation augmented both basal and cytokine-induced STAT6 phosphorylation without affecting dephosphorylation kinetics. Treatment with the Janus kinase 1/2 inhibitor ruxolitinib reversed STAT6 hyperresponsiveness to IL-4, normalized TH1 and TH17 cells, suppressed the eosinophilia, and improved the patient's atopic dermatitis. This study identified a novel inborn error of immunity due to a STAT6 gain-of-function mutation that gave rise to severe allergic dysregulation. Janus kinase inhibitor therapy could represent an effective targeted treatment for this disorder.

Dynamics of Age- versus Therapy-Related Clonal Hematopoiesis in Long-term Survivors of Pediatric Cancer.

This first comprehensive CH analysis in long-term survivors of pediatric cancer presents the elevated prevalence and therapy exposures/diagnostic spectrum associated with CH. Due to the contrasting dynamics of clonal expansion for age-related versus therapy-related CH, longitudinal monitoring is recommended to ascertain the long-term effects of therapy-induced CH in pediatric cancer survivors. See related commentary by Collord and Behjati, p. 811. This article is highlighted in the In This Issue feature, p. 799.

Prognostic analysis of smoldering ATLL with skin eruptions based on genomic aberrations

BackgroundPatients with smoldering ATLL often present with a skin eruption due to skin infiltration of ATLL cells. Although skin eruption type is known to be associated with prognosis based on its pattern, it is unknown why different types of skin eruptions are associated with different prognoses. ObjectiveGenomic analysis of patients with skin eruptions of smoldering ATLL will be performed to determine the mechanism of ATLL development and its association with prognosis. MethodsDNA from skin biopsy specimens was used for targeted sequencing of 280 genes to examine the association between genomic variation and prognosis. ResultsDue to the small number of smoldering ATLL patients (27 cases), we could not find a clear relationship between skin eruption and prognosis in this study. Genomic analysis identified 247 genomic variants (108 genes), with an average of 9.2 variants and 3.2 variants as driver genes. Pathway analysis of the driver genes showed activation of the pathway associated with HTLV-1 infection, as well as activation of the signaling pathway observed throughout ATLL. Furthermore, multivariate analysis identified age>70 years and STAT3 mutation as prognostic risk factors and TBL1XR1 mutation as a risk factor for progression-free survival. ConclusionAlthough the small number of patient samples did not allow us to determine a prognostic association with skin eruption, STAT3 mutation was identified as a prognostic risk factor for smoldering ATLL with skin eruption. Further studies are needed to increase the number of patients with this disease.

Follicular Lymphoma in the 5th Edition of the WHO-Classification of Haematolymphoid Neoplasms-Updated Classification and New Biological Data.

The conceptual description of Follicular lymphoma (FL) in the 5th edition of the World Health Organization (WHO) classification of haematolymphoid tumors (WHO-HAEM5) has undergone significant revision. The vast majority of FL (85%) with a follicular growth pattern are composed of centrocytes and centroblasts, harbor the t(14;18)(q32;q21) translocation and are now termed classic FL (cFL). They are set apart from three related subtypes, FL with predominantly follicular growth pattern, FL with unusual cytological features (uFL) and follicular large B-cell lymphoma (FLBCL). In contrast to the revised 4th edition of the WHO classification of haematolymphoid tumors (WHO-HAEM4R), grading of cFL is no longer mandatory. FL with a predominantly diffuse growth pattern had been previously recognized in WHO-HAEM4R. It frequently occurs as a large tumor in the inguinal region and is associated with CD23 expression. An absence of the IGH::BCL2 fusion and frequent STAT6 mutations along with 1p36 deletion or TNFRSF14 mutation is typical. The newly introduced subtype of uFL includes two subsets that significantly diverge from cFL: one with "blastoid" and one with "large centrocyte" variant cytological features. uFL more frequently displays variant immunophenotypic and genotypic features. FLBCL is largely identical to WHO-HAEM4R FL grade 3B and renaming was done for reasons of consistency throughout the classification. In-situ follicular B-cell neoplasm, pediatric-type FL, duodenal-type FL and primary cutaneous follicle center lymphoma are categorized as discrete entities. In addition, novel findings concerning underlying biological mechanisms in the pathogenesis of early and systemic follicular lymphoma will be presented.

Sequence analyses of relapsed or refractory diffuse large B-cell lymphomas unravel three genetic subgroups of patients and the GNA13 mutant as poor prognostic biomarker, results of LNH-EP1 study.

Advances in molecular profiling of newly diagnosed diffuse large B-cell lymphoma (DLBCL) have recently refine genetic subgroups. Genetic subgroups remain undetermined at the time of relapse or refractory (RR) disease. This study aims to decipher genetic subgroups and search for prognostic molecular biomarkers in patients with RR-DLBCL. From 2015 to 2021, targeted next-generation sequencing analyses of germline-matched tumor samples and fresh tissue from RR-DLBCL patients were performed. Unsupervised clustering of somatic mutations was performed and correlations with patient outcome were sought. A number of 120 patients with RR-DLBCL were included in LNH-EP1 study and a molecular tumor landscape was successfully analyzed in 87% of patients (104/120 tumor samples). The median age was 67.5 years (range 27.4-87.4), median number of previous treatments was 2 (range 1-9). The most frequently mutated genes were TP53 (n=53 mutations; 42% of samples), CREBBP (n=39; 32%), BCL2 (n=86; 31%), KMT2D (n=39; 28%) and PIM1 (n=54; 22%). Unsupervised clustering separated three genetic subgroups entitled BST (enriched in BCL2, SOCS1, and TNFRSF14 mutations); TKS (enriched in TP53, KMT2D, and STAT6 mutations); and PCM (enriched in PIM1, CD79B, and MYD88 mutations). Median overall survival (OS) was 11.0 (95% confidence interval [CI]: 8.1-12.6) months. OS was not significantly different between the three genetic subgroups. GNA13 mutant was significantly associated with an increased risk of death (hazard ratio: 6.6 [95% CI: 2.1-20.6]; p=.0011) and shorter OS (p=.0340). At the time of relapse or refractory disease, three genetic subgroups of DLBCL patients were delineated, which could help advance precision molecular medicine programs.

STAT3 mutation-associated airway epithelial defects in Job syndrome

Job syndrome is a disease of autosomal dominant hyper-IgE syndrome (AD-HIES). Patients harboring STAT3 mutation are particularly prone to airway remodeling and airway infections. Airway epithelial cells play a central role as the first line of defense against pathogenic infection and express high levels of STAT3. This study thus interrogates how AD-HIES STAT3 mutations impact the physiological functions of airway epithelial cells. This study created human airway basal cells expressing 4 common AD-HIES STAT3 mutants (R382W, V463del, V637M, and Y657S). In addition, primary airway epithelial cells were isolated from a patient with Job syndrome who was harboring a STAT3-S560del mutation and from mice harboring a STAT3-V463del mutation. Cell proliferation, differentiation, barrier function, bacterial elimination, and innate immune responses to pathogenic infection were quantitatively analyzed. STAT3 mutations reduce STAT3 protein phosphorylation, nuclear translocation, transcription activity, and protein stability in airway basal cells. As a consequence, STAT3-mutated airway basal cells give rise to airway epithelial cells with abnormal cellular composition and loss of coordinated mucociliary clearance. Notably, AD-HIES STAT3 airway epithelial cells are defective in bacterial killing and fail to initiate vigorous proinflammatory responses and neutrophil transepithelial migration in response to an experimental model of Pseudomonas aeruginosa infection. AD-HIES STAT3 mutations confer numerous abnormalities to airway epithelial cells in cell differentiation and host innate immunity, emphasizing their involvement in the pathogenesis of lung complications in Job syndrome. Therefore, therapies must address the epithelial defects as well as the previously noted immune cell defects to alleviate chronic infections in patients with Job syndrome.

Intraoral and maxillofacial abnormalities in patients with autosomal dominant hyper-IgE syndrome.

Autosomal dominant hyper-IgE syndrome (AD-HIES) is an inborn error of immunity (IEI) caused by a dominant-negative mutation in the signal transducer and activator of transcription 3 (STAT 3). This disease is characterized by chronic eczematoid dermatitis, recurrent staphylococcal skin abscesses, pneumonia, pneumatoceles, and extremely high serum IgE levels. Loss-of-function STAT3 mutations may also result in distinct non-immunologic features such as dental, facial, skeletal, and vascular abnormalities, central nervous system malformations and an increased risk for bone fractures. Prophylactic treatment of Candida infections and prophylactic antimicrobial therapy for staphylococcal skin infections and sinopulmonary infections are essential. An awareness of the oral and maxillofacial features of HIES may facilitate early diagnosis with genetic counselling and may improve future patient care. This study describes oral, dental, and maxillofacial manifestations in 14 patients with genetically defined AD-HIES. We also review the literature and propose recommendations for the complex care of patients with this rare primary immunodeficiency.

In Silico Analyses of All STAT3 Missense Variants Leading to Explore Divergent AD-HIES Clinical Phenotypes.

Autosomal dominant hyper-IgE syndrome (AD-HIES) is linked to dominant negative mutations of the STAT3 protein whose molecular basis for dysfunction is unclear and presenting with a variety of clinical manifestations with only supportive treatment. To establish the relationship between the impact of STAT3 mutations in different domains and the severity of the clinical manifestations, 105 STAT3 mutations were analyzed for their impact on protein stability, flexibility, function, and binding affinity using in Silico approaches. Our results showed that 73% of the studied mutations have an impact on the physicochemical properties of the protein, altering the stability, flexibility and function to varying degrees. In particular, mutations affecting the DNA binding domain (DBD) and the Src Homology 2 (SH2) have a significant impact on the protein structure and disrupt its interaction either with DNA or other STAT3 to form a heterodomain complex, leading to severe clinical phenotypes. Collectively, this study suggests that there is a close relationship between the domain involving the mutation, the degree of variation in the properties of the protein and the degree of loss of function ranging from partial loss to complete loss, explaining the variability of clinical manifestations between mild and severe.

Butyrate facilitates immune clearance of colorectal cancer cells by suppressing STAT1-mediated PD-L1 expression

ObjectiveImmunotherapy has been proven to improve the prognosis of patients with advanced malignancy but has shown limited efficacy in patients with Colorectal Cancer (CRC). Increasing evidence suggests that butyrate, a bacterial metabolite, enhances the efficacy of cancer therapies by modulating immune responses. Here, the effect and the mechanism of butyrate on anti-PD-L1 therapy were investigated in CRC. MethodsThe expression of PD-L1 and STAT1, and the lysine acetylation of STAT1 in CRC cells were observed after treatment with butyrate (2, 5, and 10 mM) for 24h or butyrate (5 mM) for 8, 16, and 24h. Site-directed mutations of STAT1 (K410R or K413R) were introduced to determine the role of STAT1 acetylation in modulating PD-L1 expression. The effect of butyrate on the cytotoxicity of CD8+ T-cells against CRC cells with or without PD-L1 overexpression was explored in vitro and in vivo. ResultsButyrate could suppress IFN-γ-induced PD-L1 up-regulation in CRC cells in a dose- and time-dependent way. Butyrate promoted the lysine acetylation of STAT1 to reduce STAT1 expression. Non-acetylated mutant STAT1 not only ameliorated butyrate-induced suppression of lysine acetylation and nuclear translocation of STAT1 but also blocked the effect of butyrate on PD-L1. Butyrate attenuated the IFN-γ-induced impairment of CD8+ T-cell cytotoxicity against CRC cells. Meanwhile, butyrate suppressed CRC tumor growth by enhancing CD8+ T-cell infiltration. However, directly overexpressing PD-L1 in CRC cells could abolish the effect of butyrate. ConclusionButyrate strengthens the immune response to CRC cells by suppressing PD-L1 expression via acetylation of STAT1.