Sequential inverse dysregulation of the RNA helicases DDX3X and DDX3Y facilitates MYC-driven lymphomagenesis.

DDX3X is a ubiquitously expressed RNA helicase involved in multiple stages of RNA biogenesis. DDX3X is frequently mutated in Burkitt lymphoma, but the functional basis for this is unknown. Here, we show that loss-of-function DDX3X mutations are also enriched in MYC-translocated diffuse large B cell lymphoma and reveal functional cooperation between mutant DDX3X and MYC. DDX3X promotes the translation of mRNA encoding components of the core translational machinery, thereby driving global protein synthesis. Loss-of-function DDX3X mutations moderate MYC-driven global protein synthesis, thereby buffering MYC-induced proteotoxic stress during early lymphomagenesis. Established lymphoma cells restore full protein synthetic capacity by aberrant expression of DDX3Y, a Y chromosome homolog, the expression of which is normally restricted to the testis. These findings show that DDX3X loss of function can buffer MYC-driven proteotoxic stress and highlight the capacity of male B cell lymphomas to then compensate for this loss by ectopic DDX3Y expression.

Tyrosine phosphatases regulate resistance to ALK inhibitors in ALK+ anaplastic large cell lymphoma.

Anaplastic large cell lymphomas (ALCLs) frequently carry oncogenic fusions involving the anaplastic lymphoma kinase (ALK) gene. Targeting ALK using tyrosine kinase inhibitors (TKIs) is a therapeutic option in cases relapsed after chemotherapy, but TKI resistance may develop. By applying genomic loss-of-function screens, we identified PTPN1 and PTPN2 phosphatases as consistent top hits driving resistance to ALK TKIs in ALK+ ALCL. Loss of either PTPN1 or PTPN2 induced resistance to ALK TKIs in vitro and in vivo. Mechanistically, we demonstrated that PTPN1 and PTPN2 are phosphatases that bind to and regulate ALK phosphorylation and activity. In turn, oncogenic ALK and STAT3 repress PTPN1 transcription. We found that PTPN1 is also a phosphatase for SHP2, a key mediator of oncogenic ALK signaling. Downstream signaling analysis showed that deletion of PTPN1 or PTPN2 induces resistance to crizotinib by hyperactivating SHP2, the MAPK, and JAK/STAT pathways. RNA sequencing of patient samples that developed resistance to ALK TKIs showed downregulation of PTPN1 and PTPN2 associated with upregulation of SHP2 expression. Combination of crizotinib with a SHP2 inhibitor synergistically inhibited the growth of wild-type or PTPN1/PTPN2 knock-out ALCL, where it reverted TKI resistance. Thus, we identified PTPN1 and PTPN2 as ALK phosphatases that control sensitivity to ALK TKIs in ALCL and demonstrated that a combined blockade of SHP2 potentiates the efficacy of ALK inhibition in TKI-sensitive and -resistant ALK+ ALCL.

STAT3/LKB1 controls metastatic prostate cancer by regulating mTORC1/CREB pathway.

Prostate cancer (PCa) is a common and fatal type of cancer in men. Metastatic PCa (mPCa) is a major factor contributing to its lethality, although the mechanisms remain poorly understood. PTEN is one of the most frequently deleted genes in mPCa. Here we show a frequent genomic co-deletion of PTEN and STAT3 in liquid biopsies of patients with mPCa. Loss of Stat3 in a Pten-null mouse prostate model leads to a reduction of LKB1/pAMPK with simultaneous activation of mTOR/CREB, resulting in metastatic disease. However, constitutive activation of Stat3 led to high LKB1/pAMPK levels and suppressed mTORC1/CREB pathway, preventing mPCa development. Metformin, one of the most widely prescribed therapeutics against type 2 diabetes, inhibits mTORC1 in liver and requires LKB1 to mediate glucose homeostasis. We find that metformin treatment of STAT3/AR-expressing PCa xenografts resulted in significantly reduced tumor growth accompanied by diminished mTORC1/CREB, AR and PSA levels. PCa xenografts with deletion of STAT3/AR nearly completely abrogated mTORC1/CREB inhibition mediated by metformin. Moreover, metformin treatment of PCa patients with high Gleason grade and type 2 diabetes resulted in undetectable mTORC1 levels and upregulated STAT3 expression. Furthermore, PCa patients with high CREB expression have worse clinical outcomes and a significantly increased risk of PCa relapse and metastatic recurrence. In summary, we have shown that STAT3 controls mPCa via LKB1/pAMPK/mTORC1/CREB signaling, which we have identified as a promising novel downstream target for the treatment of lethal mPCa.

Patient-derived xenograft models of ALK+ ALCL reveal preclinical promise for therapy with brigatinib.

Anaplastic large-cell lymphoma (ALCL) is a T-cell malignancy predominantly driven by the oncogenic anaplastic lymphoma kinase (ALK), accounting for approximately 15% of all paediatric non-Hodgkin lymphoma. Patients with central nervous system (CNS) relapse are particularly difficult to treat with a 3-year overall survival of 49% and a median survival of 23.5 months. The second-generation ALK inhibitor brigatinib shows superior penetration of the blood-brain barrier unlike the first-generation drug crizotinib and has shown promising results in ALK+ non-small-cell lung cancer. However, the benefits of brigatinib in treating aggressive paediatric ALK+ ALCL are largely unknown. We established a patient-derived xenograft (PDX) resource from ALK+ ALCL patients at or before CNS relapse serving as models to facilitate the development of future therapies. We show in vivo that brigatinib is effective in inducing the remission of PDX models of crizotinib-resistant (ALK C1156Y, TP53 loss) ALCL and furthermore that it is superior to crizotinib as a second-line approach to the treatment of a standard chemotherapy relapsed/refractory ALCL PDX pointing to brigatinib as a future therapeutic option.

Induction of Transcriptional Inhibitor HES1 and the Related Repression of Tumor-Suppressor TXNIP Are Important Components of Cell-Transformation Program Imposed by Oncogenic Kinase NPM-ALK.

This study reports that hairy and enhancer of split homolog-1 (HES1), known to repress gene transcription in progenitor cells of several cell lineages, was strongly expressed in cells and tissues of T-cell lymphoma expressing the oncogenic chimeric tyrosine kinase nucleophosmin (NPM)-anaplastic lymphoma kinase [ALK; ALK+ T-cell lymphoma (TCL)]. The structural analysis of the Orange domain of HES1 indicated that HES1 formed a highly stable homodimer. Of note, repression of HES1 expression led to inhibition of ALK+ TCL cell growth in vivo. The expression of the HES1 gene was induced by NPM-ALK through activation of STAT3, which bound to the gene's promoter and induced the gene's transcription. NPM-ALK also directly phosphorylated HES1 protein. In turn, HES1 up-regulated and down-regulated in ALK+ TCL cells, the expression of numerous genes, protein products of which are involved in key cell functions, such as cell proliferation and viability. Among the genes inhibited by HES1 was thioredoxin-interacting protein (TXNIP), encoding a protein implicated in promotion of cell death in various types of cells. Accordingly, ALK+ TCL cells and tissues lacked expression of TXNIP, and its transcription was co-inhibited by HES1 and STAT3 in an NPM-ALK-dependent manner. Finally, the induced expression of TXNIP induced massive apoptotic cell death of ALK+ TCL cells. The results reveal a novel NPM-ALK-controlled pro-oncogenic regulatory network and document an important role of HES and TXNIP in the NPM-ALK-driven oncogenesis, with the former protein displaying oncogenic and the latter tumor suppressor properties.

Directive clinique no 443b : Opioïdes aux différentes étapes de la vie des femmes : Grossesse et allaitement.

OBJECTIF: Présenter aux professionnels de la santé les données probantes concernant l'utilisation des opioïdes et la santé des femmes. Les domaines d'intérêt sont la grossesse et les soins post-partum. POPULATION CIBLE: Toutes les femmes qui utilisent des opioïdes. RéSULTATS: Un dialogue ouvert et éclairé sur l'utilisation des opioïdes améliorera les soins aux patientes. BéNéFICES, RISQUES ET COûTS: L'exploration de l'utilisation d'opioïdes par une approche tenant compte des traumatismes antérieurs donne au professionnel de la santé et à la patiente l'occasion de bâtir une alliance solide, collaborative et thérapeutique. Cette alliance permet aux femmes de faire des choix éclairés. Elle favorise le diagnostic et le traitement possible du trouble lié à l'utilisation d'opioïdes. L'utilisation ne doit pas être stigmatisée, puisque la stigmatisation affaiblit le partenariat (le partenariat entre patiente et professionnel de la santé). Les professionnels de la santé ceus-ci doivent comprendre l'effet potentiel des opioïdes sur la santé les femmes enceintes et les aider à prendre des décisions éclairées sur leur santé. DONNéES PROBANTES: Une recherche a été conçue puis effectuée dans les bases de données PubMed et Cochrane Library pour la période d'août 2018 à mars 2023 des termes MeSH et mots clés suivants (et variantes) : opioids, opioid agonist therapy, illicit drugs, fertility, pregnancy, fetal development, neonatal abstinence syndrome et breastfeeding. MéTHODES DE VALIDATION: Les auteurs ont évalué la qualité des données probantes et la force des recommandations en utilisant le cadre méthodologique GRADE (Grading of Recommendations, Assessment, Development, and Evaluation). Voir l'annexe A en ligne (tableau A1 pour les définitions et tableau A2 pour l'interprétation des recommandations fortes et conditionnelles [faibles]). PROFESSIONNELS CONCERNéS: Tous les professionnels de la santé qui prodiguent des soins aux femmes et aux nouveaux-nés. RéSUMé POUR TWITTER: La consommation d'opioïdes pendant la grossesse coïncide souvent avec des problèmes de santé mentale et est associée à des conséquences néfastes pour la mère, le fœtus et le nouveau-né ; le traitement des troubles liés à la consommation d'opioïdes par agonistes peut être sûr pendant la grossesse lorsque les risques sont plus nombreux que les avantages. DÉCLARATIONS SOMMAIRES: RECOMMANDATIONS.

Guideline No. 443a: Opioid Use Throughout Women's Lifespan: Fertility, Contraception, Chronic Pain, and Menopause.

OBJECTIVE: To provide health care providers with the best evidence on opioid use and women's health. Areas of focus include general patterns of opioid use and safety of use; care of women who use opioids; stigma, screening, brief intervention, and referral to treatment; hormonal regulation; reproductive health, including contraception and fertility; sexual function; perimenopausal and menopausal symptoms; and chronic pelvic pain syndromes. TARGET POPULATION: The target population includes all women currently using or contemplating using opioids. OUTCOMES: Open, evidence-informed dialogue about opioid use will lead to improvements in patient care and overall health. BENEFITS, HARMS, AND COSTS: Exploring opioid use through a trauma-informed approach offers the health care provider and patient with an opportunity to build a strong, collaborative, and therapeutic alliance. This alliance empowers women to make informed choices about their own care. It also allows for the diagnosis and possible treatment of opioid use disorders. Use should not be stigmatized, as stigma leads to poor "partnered care" (i.e., the partnership between the patient and care provider). Therefore, health care providers and patients must understand the potential role of opioids in women's health (both positive and negative) to ensure informed decision-making. EVIDENCE: A literature search was designed and carried out in PubMed and the Cochrane Library databases from August 2018 until March 2023 using following MeSH terms and keywords (and variants): opioids, illicit drugs, fertility, pregnancy, breastfeeding, and aging. VALIDATION METHODS: The authors rated the quality of evidence and strength of recommendations using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. See online Appendix A (Tables A1 for definitions and A2 for interpretations of strong and weak recommendations). INTENDED AUDIENCE: All health care providers who care for women. TWEETABLE ABSTRACT: Opioid use can affect female reproductive function; health care providers and patients must understand the potential role of opioids in women's health to ensure informed decision-making. SUMMARY STATEMENTS: RECOMMENDATIONS.

Guideline No. 443b: Opioid Use Throughout Women's Lifespan: Opioid Use in Pregnancy and Breastfeeding.

OBJECTIVE: To provide health care providers the best evidence on opioid use and women's health. Areas of focus include pregnancy and postpartum care. TARGET POPULATION: The target population includes all women currently using or contemplating using opioids. OUTCOMES: Open, evidence-informed dialogue about opioid use will improve patient care. BENEFITS, HARMS, AND COSTS: Exploring opioid use through a trauma-informed approach provides the health care provider and patient with an opportunity to build a strong, collaborative, and therapeutic alliance. This alliance empowers women to make informed choices about their own care. It also allows for the diagnosis and possible treatment of opioid use disorders. Opioid use should not be stigmatized, as stigma leads to poor "partnered care" (i.e., the partnership between the patient and care provider). Health care providers need to understand the effect opioids can have on pregnant women and support them to make knowledgeable decisions about their health. EVIDENCE: A literature search was designed and carried out in PubMed and the Cochrane Library databases from August 2018 until March 2023 using following MeSH terms and keywords (and variants): opioids, opioid agonist therapy, illicit drugs, fertility, pregnancy, fetal development, neonatal abstinence syndrome, and breastfeeding. VALIDATION METHODS: The authors rated the quality of evidence and strength of recommendations using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. See online Appendix A (Tables A1 for definitions and A2 for interpretations of strong and conditional [weak] recommendations). INTENDED AUDIENCE: All health care providers who care for pregnant and/or post-partum women and their newborns. TWEETABLE ABSTRACT: Opioid use during pregnancy often co-occurs with mental health issues and is associated with adverse maternal, fetal, and neonatal outcomes; treatment of opioid use disorder with agonist therapy for pregnant women can be safe during pregnancy where the risks outnumber the benefits. SUMMARY STATEMENTS: RECOMMENDATIONS.

Ultrasmall silica nanoparticles directly ligate the T cell receptor complex.

The impact of ultrasmall nanoparticles (<10-nm diameter) on the immune system is poorly understood. Recently, ultrasmall silica nanoparticles (USSN), which have gained increasing attention for therapeutic applications, were shown to stimulate T lymphocytes directly and at relatively low-exposure doses. Delineating underlying mechanisms and associated cell signaling will hasten therapeutic translation and is reported herein. Using competitive binding assays and molecular modeling, we established that the T cell receptor (TCR):CD3 complex is required for USSN-induced T cell activation, and that direct receptor complex-particle interactions are permitted both sterically and electrostatically. Activation is not limited to αß TCR-bearing T cells since those with γδ TCR showed similar responses, implying that USSN mediate their effect by binding to extracellular domains of the flanking CD3 regions of the TCR complex. We confirmed that USSN initiated the signaling pathway immediately downstream of the TCR with rapid phosphorylation of both ζ-chain-associated protein 70 and linker for activation of T cells protein. However, T cell proliferation or IL-2 secretion were only triggered by USSN when costimulatory anti-CD28 or phorbate esters were present, demonstrating that the specific impact of USSN is in initiation of the primary, nuclear factor of activated T cells-pathway signaling from the TCR complex. Hence, we have established that USSN are partial agonists for the TCR complex because of induction of the primary T cell activation signal. Their ability to bind the TCR complex rapidly, and then to dissolve into benign orthosilicic acid, makes them an appealing option for therapies targeted at transient TCR:CD3 receptor binding.

Evaluating the baseline survival outcomes of the "six Global Initiative for Childhood Cancer index cancers" in Africa.

Limited survival data for the six Global Initiative for Childhood Cancer (GICC) priority cancers are available in Africa. Management of pediatric malignancies in Africa is challenging due to lack of resources, setting-specific comorbidities, high rates of late presentation and treatment abandonment. Reporting of outcome data is problematic due to the lack of registries. With the aim of evaluating the feasibility of baseline outcomes for the six index cancers, we present a descriptive analysis of respective survival rates in Africa. The survival rates were between 18% (lower middle-income countries) to 82.3% (upper middle-income countries) for acute lymphoblastic leukemia, between 26.9% (low-income countries) to 77.9% (upper middle-income countries) for nephroblastoma, between 23% (low-income countries) to 100% (upper middle-income countries), for retinoblastoma, 45% (low-income countries) to 95% (upper middle-income countries) for Hodgkin lymphoma and 28% (low-income countries) to 76% (upper middle-income countries) for Burkitt lymphoma. Solutions to improve survival rates and reported outcomes include establishing and funding sustainable registries, training and to actively include all countries in consortia from different African regions.HighlightsContinental differences in childhood cancer management such lack of resources, setting-specific comorbidities, high rates of late presentation and treatment abandonment, present challenges to the achievement of Global Initiative for Childhood Cancer goals.The available data registries do not adequately inform on the true incidences and outcomes of childhood cancers in Africa.The pathophysiology of some childhood cancers in Africa are associated with high-risk prognostic factors.Outcomes can be improved by greater regional collaboration to manage childhood cancer based on local resources and tumor characteristics.Some individual countries have reached the Global Initiative for Childhood Cancer goals for single cancers and it should be possible for more African countries to follow suit.