Management of breakthrough bleeding in transgender and gender diverse individuals on testosterone.

BACKGROUND: While many transgender and gender diverse individuals rapidly achieve amenorrhea on testosterone, emerging data have identified that breakthrough bleeding can occur in up to one-third of individuals with long-term use. Breakthrough bleeding can worsen dysphoria and patients may seek management to reattain amenorrhea. Because of this, there is a need to assess efficacy of management approaches. OBJECTIVE: The primary aim of the study was to evaluate methods used by patients and their providers to manage breakthrough bleeding which arises after 1 year of testosterone use. Secondary aims included describing the diagnostic approaches to breakthrough bleeding, and proposing an algorithm for classification and management of breakthrough bleeding in this patient population. STUDY DESIGN: This was an institutional review board-approved single tertiary center, retrospective chart review of transgender and gender diverse individuals on testosterone gender affirming hormone therapy who experienced breakthrough bleeding after 1 year of use. Charts were reviewed to determine patient characteristics, testosterone use, and breakthrough bleeding management approaches. RESULTS: Of the 96 individuals who had been on testosterone for 1 year and experienced breakthrough bleeding, 97% (n=93) engaged in at least 1 approach to management. The mean age at initiation of testosterone was 21.9 (standard deviation 5.4) and the median duration of time on testosterone was 54.5 months (interquartile range 33.5, 82). Only 16% (n=15) were using menstrual suppression at the time of their breakthrough bleeding episode. Breakthrough bleeding was successfully managed in 77 (79%), following between 1 and 4 attempted approaches. More than half of management attempts (63%) were successful on the first try. When management approaches were analyzed independently, the range of success associated with any particular approach was between 33% and 100%. Other than hysterectomy, which was fully successful at managing breakthrough bleeding, no approach was significantly better than no intervention. This was true both for individuals who did and did not bleed with missed testosterone doses. Regardless of what approach was used, after a failed attempt, the next attempt was successful in more than half of individuals. Of the 16 who underwent hysterectomy, 1 did so in part as a first line approach to manage breakthrough bleeding. CONCLUSION: In this study, use of medical management methods was not found to be superior to observation alone in the management of breakthrough bleeding. In the absence of data supporting superiority of any method, we recommend tailoring method attempts to patients' goals.

B cells on the brink.

Type 2-polarized memory B cells sustain food allergy and allergic rhinitis by rapidly differentiating into pathogenic IgE-producing plasma cells.

Mast cells express IL17A, IL17F and RORC, are activated and persist with IL-17 production in resolved skin of patients with chronic plaque-type psoriasis.

Little is known about IL-17 expression in psoriasis and the actual cellular source of IL-17 remains incompletely defined. We show that high numbers of IL-17 + mast cells persisted in resolved lesions after treatment (anti-IL-17A, anti-IL-23, UVB or topical dithranol) and correlated inversely with the time span in remission. IL-17 + mast cells were found in T cell-rich areas and often close to resident memory T cells (Trm) in active psoriasis and resolved lesional skin. Digital cytometry by deconvolution of RNA-seq data showed that activated mast cells were increased in psoriatic skin, while resting mast cells were almost absent and both returned to normal levels after treatment. When primary human skin mast cells were stimulated with T cell cytokines (TNFα, IL-22 and IFNγ), they responded by releasing more IL-17A, as measured by ELISA. In situ mRNA detection using padlock probes specific for transcript variants of IL17A, IL17F, and RORC (encoding the Th17 transcription factor RORγt) revealed positive mRNA signals for IL17A, IL17F, and RORCin tryptase + cells, demonstrating that mast cells have the transcriptional machinery to actively produce IL-17. Mast cells thus belong to the center of the IL-23/IL-17 axis and high numbers of IL-17 + mast cells predict an earlier disease recurrence.

Incidence of breakthrough bleeding in transgender and gender-diverse individuals on long-term testosterone.

BACKGROUND: Little is known about the maintenance of amenorrhea among transgender and gender-diverse individuals with uteri who are using long-term testosterone gender-affirming hormone therapy. Emerging data describe breakthrough bleeding among adolescents on long-term testosterone therapy and among adults who are seeking a gender-affirming hysterectomy. More studies are needed to better understand breakthrough bleeding patterns among transgender and gender-diverse individuals with uteri who are using testosterone, including the frequency, timing, and etiology of bleeding and how these patterns may differ between adults and younger populations. OBJECTIVE: The primary aim of this study was to characterize the incidence and patterns of breakthrough bleeding in a cohort of transgender and gender-diverse individuals who had been on testosterone for longer than 12 months and who had uteri in situ. Secondary aims included identifying the time to first bleed for those who experienced breakthrough bleeding and the risk factors associated with breakthrough bleeding while on testosterone therapy. STUDY DESIGN: This was an institutional review board-approved, single tertiary center, retrospective chart review of transgender and gender diverse individuals who had been on testosterone for at least 1 year. A primary survival analysis that evaluated the incidence of bleeding was combined with descriptive analyses and an evaluation of the factors associated with bleeding. RESULTS: Of the 279 patients included in the analysis, the median age of testosterone initiation was 22 years (interquartile range, 19-41), and the median follow-up time was 34 months (range, 12-278). The absolute proportion of individuals who ever experienced breakthrough bleeding on testosterone was 34% (n=96; 95% confidence interval, 29-40). Patients who experienced breakthrough bleeding initiated testosterone at a younger age (20.5 vs 22.0 years; P=.04), had lower mean serum testosterone levels (389.14 vs 512.7 ng/dL; P=.001), were more likely to have a mean testosterone level <320 ng/dL (52% vs 48%; P=.001), and had higher mean estradiol levels (62% vs 49%; P=.003). Survival analyses estimated a breakthrough bleeding incidence rate of 0.09 per year (95% confidence interval, 0.07-1.0). Although 58 people underwent a hysterectomy during the follow-up period, 64% of the cohort who maintained a uterus eventually experienced breakthrough bleeding. The median time to the initial bleeding episode was 22 months (interquartile range, 12-201) after testosterone initiation. CONCLUSION: These results suggest that a substantial fraction of transgender and gender-diverse individuals who are using testosterone will experience at least 1 episode of breakthrough bleeding even after their initial year of testosterone use. We recommend that clinicians inform all patients that breakthrough bleeding is a common occurrence even after the first year on testosterone therapy.

A Description of IVIG Use in Term Neonates with ABO Incompatibility.

OBJECTIVE: This study aimed to determine if treatment with IVIG of neonates with ABO incompatibility (without Rh incompatibility) results in decreased number of packed red blood cell (pRBC) transfusions and phototherapy use. STUDY DESIGN: An Institutional Review Board (IRB)-approved, single-institution retrospective study was conducted. Neonates ≥38 weeks' gestational age born between January 1, 2007, and December 31, 2016, with ABO incompatibility were included. The comparison among groups was performed using chi-square and Fisher's exact tests for categorical variables; continuous variables were assessed by Kruskal-Wallis test. RESULTS: Six hundred and sixty-eight neonates with ABO incompatibility met inclusion criteria, 579 were included in the analyses. From these, 431 (74%) neonates had positive Direct Antiglobulin Test (DAT); 98 (17%) received IVIG and 352 (61%) received phototherapy. Thirty-six (6%) neonates received pRBC and 6 (1%) required exchange transfusions. Only 3 (0.5%) infants received pRBC transfusions postdischarge, by 3 months of age. Neonates requiring IVIG had lower initial hemoglobin (13.6 vs. 16.0 g/dL, p ≤ 0.0001) and higher bilirubin at start of phototherapy (9.1 vs. 8.1 mg/dL, p = 0.0064). From the 42 (7%) neonates who received simple and exchange transfusions, IVIG use was not associated with decreased use or number of transfusions (p = 0.5148 and 0.3333, respectively). Newborns with A+ and B+ blood types had comparable initial hemoglobin, DAT positivity, APGAR, and bilirubin. However, infants with B+ blood group were more likely (than A + ) to require phototherapy (p < 0.001), receive IVIG (p = 0.003), and need phototherapy for a longer duration (p = 0.001). CONCLUSION: The results of this large retrospective study reveal that giving IVIG to neonates with ABO incompatibility was associated with increased simple or exchange transfusions. Newborns with B+ blood type required more phototherapy and IVIG. Further studies are needed to better stratify neonates who would benefit from IVIG use in order to optimize treatment strategies and avoid unnecessary risks and adverse events. KEY POINTS: · IVIG use not associated with decreased use of pRBC or exchanges.. · Phototherapy duration associated with increased IVIG and pRBC use.. · Newborns with B+ blood type had worse hemolytic anemia..

Comparative Quantitative Proteomic Analysis of Melanoma Subtypes, Nevus-Associated Melanoma, and Corresponding Nevi.

A substantial part of cutaneous malignant melanomas develops from benign nevi. However, the precise molecular events driving the transformation from benign to malignant melanoma are not well-understood. We used laser microdissection and mass spectrometry to analyze the proteomes of melanoma subtypes, including superficial spreading melanomas (n = 17), nodular melanomas (n = 17), and acral melanomas (n = 15). Furthermore, we compared the proteomes of nevi cells with those of melanoma cells within the same specimens (nevus-associated melanoma (n = 14)). In total, we quantified 7935 proteins. Despite the genomic and clinical differences of the melanoma subtypes, our analysis revealed relatively similar proteomes, except for the upregulation of proteins involved in immune activation in nodular melanomas versus acral melanomas. Examining nevus-associated melanoma versus nevi, we found 1725 differentially expressed proteins (false discovery rate < 0.05). Among these proteins were 140 that overlapped with cancer hallmarks, tumor suppressors, and regulators of metabolism and cell cycle. Pathway analysis indicated aberrant activation of the phosphoinositide 3-kinase-protein kinase B-mTOR pathways and the Hippo-YAP pathway. Using a classifier, we identified six proteins capable of distinguishing melanoma from nevi samples. Our study represents a comprehensive comparative analysis of the proteome in melanoma subtypes and associated nevi, offering insights into the biological behavior of these distinct entities.

In-Depth Proteomic Map of Innate Lymphoid Cells from Healthy Human Skin and Blood.

Innate lymphoid cells (ILCs) are essential players in the skin-associated immune system, nevertheless little is known about their proteomes and proteomic diversity. In this study, we describe about 6,600 proteins constitutively expressed by ILC2s and ILC3s from healthy human skin and blood using state-of-the-art proteomics. Although the vast majority of proteins was expressed by both ILC subsets and in both compartments, the skin ILC2s and ILC3s were more distinct than their counterparts in blood. Only skin ILC3s expressed uniquely detected proteins. Our in-depth proteomic dataset allowed us to define the cluster of differentiation marker profiles of the ILC subsets, explore distribution and abundance of proteins known to have immunological functions, as well as identify subset-specific proteins that have not previously been implicated in ILC biology. Taken together, our analyses substantially expand understanding of the protein expression signatures of ILC subsets. Going forward, these proteomic datasets will serve as valuable resources for future studies of ILC biology.

Phototherapy Restores Deficient Type I IFN Production and Enhances Antitumor Responses in Mycosis Fungoides.

Transcriptional profiling demonstrated markedly reduced type I IFN gene expression in untreated mycosis fungoides (MF) skin lesions compared with that in healthy skin. Type I IFN expression in MF correlated with antigen-presenting cell-associated IRF5 before psoralen plus UVA therapy and epithelial ULBP2 after therapy, suggesting an enhancement of epithelial type I IFN. Immunostains confirmed reduced baseline type I IFN production in MF and increased levels after psoralen plus UVA treatment in responding patients. Effective tumor clearance was associated with increased type I IFN expression, enhanced recruitment of CD8+ T cells into skin lesions, and expression of genes associated with antigen-specific T-cell activation. IFNk, a keratinocyte-derived inducer of type I IFNs, was increased by psoralen plus UVA therapy and expression correlated with upregulation of other type I IFNs. In vitro, deletion of keratinocyte IFNk decreased baseline and UVA-induced expression of type I IFN and IFN response genes. In summary, we find a baseline deficit in type I IFN production in MF that is restored by psoralen plus UVA therapy and correlates with enhanced antitumor responses. This may explain why MF generally develops in sun-protected skin and suggests that drugs that increase epithelial type I IFNs, including topical MEK and EGFR inhibitors, may be effective therapies for MF.

Human Skin T Cells Express Conserved T-Cell Receptors that Cross-React with Staphylococcal Superantigens and CD1a.

Human Langerhans cells highly express CD1a antigen-presenting molecules. To understand the functions of CD1a in human skin, we used CD1a tetramers to capture T cells and determine their effector functions and TCR patterns. Skin T cells from all donors showed CD1a tetramer staining, which in three cases exceeded 10% of skin T cells. CD1a tetramer-positive T cells produced diverse cytokines, including IL-2, IL-4, IL-5, IL-9, IL-17, IL-22, and IFN-γ. Conserved TCRs often recognize nonpolymorphic antigen-presenting molecules, but no TCR motifs are known for CD1a. We detected highly conserved TCRs that used TRAV34 and TRBV28 variable genes, which is a known motif for recognition of staphylococcal enterotoxin B, a superantigen associated with atopic dermatitis. We found that these conserved TCRs did not respond to superantigen presented by CD1a, but instead showed a cross-reactive response with two targets: CD1a and staphylococcal enterotoxin B presented by classical major histocompatibility complex II. These studies identify a conserved human TCR motif for CD1a-reactive T cells. Furthermore, the demonstrated cross-reaction of T cells with two common skin-specific stimuli suggests a candidate mechanism by which CD1a and skin flora could synergize during natural immune response and in Staphylococcus-associated skin diseases.

Bacterial culture and susceptibility test results for clinical mastitis samples from Australia's subtropical dairy region.

This study aimed to identify the pathogens isolated from the milk of cows with clinical mastitis in the subtropical region of Australia and to determine the antimicrobial susceptibility of these bacteria. Thirty dairy herds in the subtropical dairy region were asked to submit milk samples for the first 5 cases of clinical mastitis each month for 12 mo. Samples underwent aerobic culture, and isolates were identified via MALDI-TOF mass spectrometry. Antimicrobial susceptibility was determined for Escherichia coli, Enterococcus spp., Streptococcus agalactiae, Streptococcus uberis, Streptococcus dysgalactiae, Staphylococcus aureus, and non-aureus staphylococci and mammaliicocci (NASM). Between March 2021 and July 2022, 1,230 milk samples were collected. A positive culture result was recorded for 812 (66%) of the milk samples; from these samples, 909 isolates were obtained, including 49 isolates where no identification was possible. The remaining samples were classified as having no growth (16.8%) or as being contaminated (17.2%). The most common isolates with a MALDI-TOF diagnosis (n = 909) were Strep. uberis (23.6%), followed by the NASM group (15.0%). Farms enrolled in the study were in 3 distinct locations within the subtropical dairy region: North Queensland, Southeast Queensland, and Northern New South Wales. Some variation in isolate prevalence occurred between these 3 locations. We found lower odds of a sample being positive for E. coli in North Queensland (odds ratio [OR]: 0.25; 95% confidence interval [CI]: 0.07-0.87) and higher odds in Southeast Queensland (OR: 4.01; 95% CI: 1.96-8.20) compared with the reference, Northern New South Wales. We further found higher odds of Strep. dysgalactiae in North Queensland (OR: 5.69; 95% CI: 1.85-17.54) and Southeast Queensland compared with Northern New South Wales (OR: 3.99; 95% CI: 1.73-9.22). Although some seasonal patterns were observed, season was not significant for any of the analyzed isolates. Farm-level differences in pathogen profiles were obvious. Overall, clinical mastitis pathogens had low levels of resistance to the antimicrobials tested. This research demonstrates that Strep. uberis and the NASM bacterial group are the most common pathogens causing clinical mastitis in the subtropical dairy region. It highlights the importance of understanding pathogenic causes of mastitis at the farm and regional level for targeted control and therapy.

Tapinarof validates the aryl hydrocarbon receptor as a therapeutic target: A clinical review.

The aryl hydrocarbon receptor (AhR) is a ligand-dependent transcription factor that has wide-ranging roles, including regulation of inflammation and homeostasis. AhR is not a cell surface receptor; rather, it exists in a cytoplasmic complex that responds to a wide variety of structurally dissimilar endogenous, microbial, and environmental ligands. The ubiquitous expression of AhR, its ability to be activated by a wide range of ligands, and its capacity to act as a master regulator for gene expression and homeostasis make it a promising new therapeutic target. Clinical trials of tapinarof cream have now validated AhR agonism as a therapeutic approach that can deliver significant efficacy for treating inflammatory skin diseases, including psoriasis and atopic dermatitis. Tapinarof 1% cream is a first-in-class, nonsteroidal, topical, AhR agonist with a pharmacokinetic profile that results in localized exposure at sites of disease, avoiding systemic safety concerns, drug interactions, or off-target effects. Psoriasis and atopic dermatitis both involve epidermal inflammation, cellular immune responses, dysregulation of skin barrier protein expression, and oxidative stress. On the basis of the clinical effectiveness of tapinarof cream for treating inflammatory skin diseases, we review how targeting AhR may offer a significant opportunity in other conditions that share key aspects of pathogenesis, including asthma, inflammatory bowel disease, eosinophilic esophagitis, ophthalmic, and nervous system diseases.

Listen to your gut: Antibodies against gut commensals predict type 1 diabetes onset and therapeutic responses to T cell modulation.

Immune responses to gut bacteria are associated with development of type 1 diabetes and predict the effectiveness of teplizumab, an anti-CD3 antibody, in delaying diabetes onset.

Prevalence of pelvic pain in transgender individuals on testosterone.

BACKGROUND: Pelvic pain has been reported in transmasculine individuals taking testosterone. There is a need for further investigation to increase understanding of the prevalence and risk factors of this pain. AIM: We sought to determine the prevalence of pelvic pain reported by transmasculine individuals who had both a uterus and ovaries and were taking testosterone. METHODS: We conducted an institutional review board-approved retrospective study of all transmasculine individuals who had been taking testosterone for at least 1 year and had a uterus and ovaries at the time of testosterone initiation. Charts of participating patients were reviewed to determine patient characteristics, testosterone use, and pelvic pain symptoms both before and after initiation of testosterone. OUTCOMES: Patients reported experiences of pelvic pain while on testosterone. RESULTS: Of 280 individuals who had been on testosterone for at least 1 year, 100 (36%) experienced pelvic pain while on testosterone. Of those patients, 71% (n = 71) had not experienced pelvic pain prior to starting testosterone. There were 42 patients (15%) who had pelvic pain prior to starting testosterone, 13 (31%) of whom no longer experienced pain once starting testosterone. The median (IQR) age at initiation of testosterone was 22 (19-41) years and duration of testosterone treatment was 48 (27-251) months.Those patients who experienced pelvic pain while on testosterone were significantly more likely to have also reported pelvic pain prior to starting testosterone (29% vs 7%, P < .001). These patients were also more likely to have a pre-existing diagnosis of dysmenorrhea (27% vs 7%, P < .001), endometriosis (6% vs 2%, P = .049), or ovarian cysts and/or masses (12% vs 2% P < .001). Patients with pelvic pain were also more likely to have been on a menstrual suppression agent prior to and overlapping testosterone initiation (22% vs 12%, P = .03) and to have used menstrual suppression for longer durations (median [IQR] 18 [6-44] vs 8 [4-15] months, P = .04). CLINICAL IMPLICATIONS: Pelvic pain is common in transmasculine individuals who are initiating testosterone treatment, although testosterone has both positive and negative effects on pelvic pain in different individuals. STRENGTHS AND LIMITATIONS: The major strengths of this study included large numbers of patients, ability to assess for documentation of pelvic pain prior to testosterone, and ability to determine an actual prevalence of pelvic pain. Major limitations included the study being a retrospective analysis in a single tertiary care center, the limitations of clinical documentation, and the lack of a standard pelvic pain evaluation process. CONCLUSION: More than one-third of transmasculine patients with a uterus and ovaries had pelvic pain while on testosterone, with the majority reporting onset of pain after initiating testosterone.

CD1a and bound lipids drive T-cell responses in human skin disease.

In addition to serving as the main physical barrier with the outside world, human skin is abundantly infiltrated with resident αß T cells that respond differently to self, infectious, microbiome, and noxious stimuli.  To study skin T cells during infection and inflammation, experimental biologists track T-cell surface phenotypes and effector functions, which are often interpreted with the untested assumption that MHC proteins and peptide antigens drive measured responses.  However, a broader perspective is that CD1 proteins also activate human T cells, and in skin, Langerhans cells (LCs) are abundant antigen presenting cells that express extremely high levels of CD1a.  The emergence of new experimental tools, including CD1a tetramers carrying endogenous lipids, now show that CD1a-reactive T cells comprise a large population of resident T cells in human skin.  Here, we review studies showing that skin-derived αß T cells directly recognize CD1a proteins, and certain bound lipids, such as contact dermatitis allergens, trigger T-cell responses. Other natural skin lipids inhibit CD1a-mediated T-cell responses, providing an entry point for the development of therapeutic lipids that block T-cell responses. Increasing evidence points to a distinct role of CD1a in type 2 and 22 T-cell responses, providing new insights into psoriasis, contact dermatitis, and other T-cell-mediated skin diseases.

High-Risk Neuroblastoma: A Surgical Perspective.

High-risk neuroblastoma requires multimodal treatment including systemic chemotherapy, surgical resection, radiation therapy, stem cell transplant, and immunotherapy. Surgeons play a vital role in obtaining local control of neuroblastoma and must therefore be knowledgeable about this complex pathology. This article provides a review of the optimal timing and extent of resection, the impact of various image-defined risk factors on surgical planning, and surgical approaches and techniques to enhance the resection of tumors in different anatomic locations.

Low-dose interleukin-2 promotes immune regulation in face transplantation: A pilot study.

Face transplantation is a life-changing procedure for patients with severe composite facial defects. However, it is hampered by high acute rejection rates due to the immunogenicity of skin allograft and toxicity linked to high doses of immunosuppression. To reduce immunosuppression-associated complications, we, for the first time in face transplant recipients, used low-dose interleukin 2 (IL-2) therapy to expand regulatory T cells (Tregs) in vivo and to enhance immune modulation, under close immunological monitoring of peripheral blood and skin allograft. Low-dose IL-2 achieved a sustained expansion (∼4-fold to 5-fold) of circulating Tregs and a reduction (∼3.5-fold) of B cells. Post-IL-2 Tregs exhibited greater suppressive function, characterized by higher expression of TIM-3 and LAG3co-inhibitory molecules. In the skin allograft, Tregs increased after low-dose IL-2 therapy. IL-2 induced a distinct molecular signature in the allograft with reduced cytotoxicity-associated genes (granzyme B and perforin). Two complications were observed during the trial: one rejection event and an episode of autoimmune hemolytic anemia. In summary, this initial experience demonstrated that low-dose IL-2 therapy was not only able to promote immune regulation in face transplant recipients but also highlighted challenges related to its narrow therapeutic window. More specific targeted Treg expansion strategies are needed to translate this approach to the clinic.

Anti-GRP-R monoclonal antibody antitumor therapy against neuroblastoma.

Standard treatment for patients with high-risk neuroblastoma remains multimodal therapy including chemoradiation, surgical resection, and autologous stem cell rescue. Immunotherapy has demonstrated success in treating many types of cancers; however, its use in pediatric solid tumors has been limited by low tumor mutation burdens. Gastrin-releasing peptide receptor (GRP-R) is overexpressed in numerous malignancies, including poorly-differentiated neuroblastoma. Monoclonal antibodies (mAbs) to GRP-R have yet to be developed but could serve as a potential novel immunotherapy. This preclinical study aims to evaluate the efficacy of a novel GRP-R mAb immunotherapy against neuroblastoma. We established four candidate anti-GRP-R mAbs by screening a single-chain variable fragment (scFv) library. GRP-R mAb-1 demonstrated the highest efficacy with the lowest EC50 at 4.607 ng/ml against GRP-R expressing neuroblastoma cells, blocked the GRP-ligand activation of GRP-R and its downstream PI3K/AKT signaling. This resulted in functional inhibition of cell proliferation and anchorage-independent growth, indicating that mAb-1 has an antagonist inhibitory role on GRP-R. To examine the antibody-dependent cellular cytotoxicity (ADCC) of GRP-R mAb-1 on neuroblastoma, we co-cultured neuroblastoma cells with natural killer (NK) cells versus GRP-R mAb-1 treatment alone. GRP-R mAb-1 mediated ADCC effects on neuroblastoma cells and induced release of IFNγ by NK cells under co-culture conditions in vitro. The cytotoxic effects of mAb-1 were confirmed with the secretion of cytotoxic granzyme B from NK cells and the reduction of mitotic tumor cells in vivo using a murine tumor xenograft model. In summary, GRP-R mAb-1 demonstrated efficacious anti-tumor effects on neuroblastoma cells in preclinical models. Importantly, GRP-R mAb-1 may be an efficacious, novel immunotherapy in the treatment of high-risk neuroblastoma patients.

Fishing with autoantibodies nets a gut bacteria that drives arthritis.

A fecal bacterial strain cross-reacts with rheumatoid arthritis autoantibodies, stimulates CD4+ T cells, and induces joint disease in mice.

Combination bromo- and extraterminal domain and poly (ADP-ribose) polymerase inhibition synergistically enhances DNA damage and inhibits neuroblastoma tumorigenesis.

PURPOSE: JQ1 is a bromo- and extraterminal (BET) domain inhibitor that downregulates MYC expression and impairs the DNA damage response. Poly (ADP-ribose) polymerase (PARP) inhibitors prevent DNA damage sensing and repair. We hypothesized that JQ1 would promote a DNA repair-deficient phenotype that sensitizes neuroblastoma cells to PARP inhibition. METHODS: Four human neuroblastoma cell lines were examined: two MYCN-amplified (BE(2)-C and IMR-32), and two non-MYCN-amplified (SK-N-SH and SH-SY5Y). Cells were treated with JQ1 (BET inhibitor), Olaparib (PARP inhibitor), or in combination to assess for therapeutic synergy of JQ1 and Olaparib. Treated cells were harvested and analyzed. Quantitative assessment of combination treatment synergy was performed using the median effect principle of Chou and Talalay. RESULTS: Combination treatment with Olaparib decreased the IC50 of JQ1 by 19.9-fold, 2.0-fold, 12.1-fold, and 2.0-fold in the BE(2)-C, IMR-32, SK-N-SH, and SH-SY5Y cell lines, respectively. In the MYCN-amplified cell lines, BE(2)-C and IMR-32, combination treatment decreased gene expression of MYCN relative to single-drug treatment alone or control. Combination treatment decreased protein expression of DNA repair proteins Ku80 and RAD51, led to accumulation of DNA damage marker phospho-histone H2A.X, and increased caspase activity. In the non-MYCN-amplified cell lines, SK-N-SH and SH-SY5Y, combination treatment induced G0/G1 cell cycle arrest. CONCLUSIONS: Combination BET and PARP inhibition synergistically inhibited neuroblastoma tumorigenesis in vitro. In MYCN-amplified neuroblastoma cells, this effect may be induced by downregulation of MYCN transcription, defects in DNA repair, accumulation of DNA damage, and apoptosis. In non-MYCN-amplified cell lines, combination treatment induced cell cycle arrest.