Increasing access to transplantation through telemedicine and patient navigation.

BACKGROUND: Hematopoietic cell transplantation (HCT) is a promising treatment for hematological diseases, yet access barriers like cost and limited transplant centers persist. Telemedicine-based patient navigation (PN) has emerged as a solution. This study presents a cost-free PN telemedicine clinic (TC) in collaboration with the National Marrow Donor Program. AIM: to assess its feasibility and impac on HCT access determined by the cumulative incidence of transplantation. METHODS: In this single-center cohort study, patients of all ages and diagnoses referred for HCT participated. Two transplant physician-navigators established patient relationships via video calls, collecting medical history, offering HCT education and recommending pretransplant tests. The analysis involved descriptive statistics and intent-to-transplant survival assessment. RESULTS: One hundred and three patients were included of whom n = 78 were referred for allogeneic HCT (alloHCT), with a median age of 28 years. The median time from initial contact to the first consult was 5 days. The cumulative incidence of transplantation was 50% at 6 months and 61% at 12 months, with varying outcomes based on HCT type. Notably, 49 patients were not transplanted, primarily due to refractory disease, progression or relapse (57.1%). Autologous HCT candidates and physician referrals were correlated with higher transplant success compared to alloHCT candidates and patients who were not referred by a physician. CONCLUSION: Our pretransplant TC was feasible, facilitating access to HCT. Disease relapse posed a significant barrier. Enhancing timely physician referrals should be a focus for future efforts.

Rituximab as a First-line Treatment for Autoimmune Hemolytic Anemia in Multicentric Castleman's Disease.

Castleman´s disease (CD) is a rare lymphoproliferative disorder. Concurrent autoimmune disease and CD are uncommon, but even more so, comorbid CD and autoimmune hemolytic anemia (AIHA). To the best of our knowledge, this case represents the first successful AIHA and multicentric CD (MCD) treatment using rituximab as first-line treatment. We present the case of a 53-year-old woman with a 10-year history of plasma cell variant CD who arrived at the emergency department with signs and symptoms of anemia. On admission, we made a preliminary diagnosis of hemolytic anemia and initiated immunosuppressive therapy with rituximab and steroids. After seven days, the patient recovered according to clinical and laboratory parameters, and we discharged her early. We portray a rare occurrence of CD and AIHA successfully treated with rituximab and steroid therapy, which makes our case unique.

Nascent shifts in renal cellular metabolism, structure, and function due to chronic empagliflozin in prediabetic mice.

Sodium-glucose cotransporter, type 2 inhibitors (SGLT2i) are emerging as the gold standard for treatment of type 2 diabetes (T2D) with renal protective benefits independent of glucose lowering. We took a high-level approach to evaluate the effects of the SGLT2i, empagliflozin (EMPA) on renal metabolism and function in a prediabetic model of metabolic syndrome. Male and female 12-wk-old TallyHo (TH) mice, and their closest genetic lean strain (Swiss-Webster, SW) were treated with a high-milk-fat diet (HMFD) plus/minus EMPA (@0.01%) for 12-wk. Kidney weights and glomerular filtration rate were slightly increased by EMPA in the TH mice. Glomerular feature analysis by unsupervised clustering revealed sexually dimorphic clustering, and one unique cluster relating to EMPA. Periodic acid Schiff (PAS) positive areas, reflecting basement membranes and mesangium were slightly reduced by EMPA. Phasor-fluorescent life-time imaging (FLIM) of free-to-protein bound NADH in cortex showed a marginally greater reliance on oxidative phosphorylation with EMPA. Overall, net urine sodium, glucose, and albumin were slightly increased by EMPA. In TH, EMPA reduced the sodium phosphate cotransporter, type 2 (NaPi-2), but increased sodium hydrogen exchanger, type 3 (NHE3). These changes were absent or blunted in SW. EMPA led to changes in urine exosomal microRNA profile including, in females, enhanced levels of miRs 27a-3p, 190a-5p, and 196b-5p. Network analysis revealed "cancer pathways" and "FOXO signaling" as the major regulated pathways. Overall, EMPA treatment to prediabetic mice with limited renal disease resulted in modifications in renal metabolism, structure, and transport, which may preclude and underlie protection against kidney disease with developing T2D.NEW & NOTEWORTHY Renal protection afforded by sodium glucose transporter, type 2 inhibitors (SGLT2i), e.g., empagliflozin (EMPA) involves complex intertwined mechanisms. Using a novel mouse model of obesity with insulin resistance, the TallyHo/Jng (TH) mouse on a high-milk-fat diet (HMFD), we found subtle changes in metabolism including altered regulation of sodium transporters that line the renal tubule. New potential epigenetic determinants of metabolic changes relating to FOXO and cancer signaling pathways were elucidated from an altered urine exosomal microRNA signature.

Graft-versus-host disease after an outpatient peripheral blood hematopoietic cell transplant using reduced-intensity conditioning: a single-center LATAM experience.

BACKGROUND: HLA compatibility predicts allogeneic hematopoietic cell transplant (allo-HCT) and graft-versus-host disease (GvHD) outcomes. There is insufficient information regarding GvHD outcomes for outpatient HLA-identical and haploidentical-HCT employing reduced-intensity conditioning (RIC). RESEARCH DESIGN AND METHODS: We compare GvHD outcomes between donor types and report risk factors associated with GvHD. Stem cell source was T-cell replete peripheral blood. GvHD prophylaxis was post-transplant cyclophosphamide (PT-CY), mycophenolic acid, and calcineurin inhibitors for haploidentical (n = 107) and oral cyclosporine (CsA) plus methotrexate i.v. for HLA-identical (n = 89) recipients. RESULTS: One hundred and ninety-six HCT transplant patients were included. aGvHD and cGvHD frequency were similar between HCT types. aGvHD severity was comparable, but severe cGvHD was less frequent in the haploidentical group (p = .011). One-hundred-day cumulative incidence (CI) of aGvHD for haploidentical and HLA-identical was 31% and 33% (p = .84); 2-year CI of cGvHD was 32% and 38% (p = .6), respectively. Haploidentical recipients had less steroid-refractory cGvHD (p = .043). Patients with cGvHD had less 2-year relapse (p = .003); both aGvHD and cGvHD conferred higher OS (p = .010 and p = .001), respectively. Male sex was protective for steroid-refractory cGvHD (p = .028). CONCLUSIONS: Acute and chronic GvHD rates were comparable between HLA-identical and haploidentical transplant groups. cGvHD severity was lower in the haploidentical group.

Factores limitantes de la formación académica de posgrado en enfermeros

Introducción: La formación académica de posgrado es un proceso continuo de incorporación de conocimientos, que se puede ver afectado por factores intrínsecos y extrínsecos. Objetivo: Determinar los factores limitantes de la formación académica de posgrado en enfermeros. Métodos: Se realizó un estudio observacional descriptivo en el Hospital Pediátrico de Camagüey durante el primer semestre de 2022. El universo estuvo constituido por 275 enfermeros, y la muestra quedó conformada por 272 que se cumplieron con los criterios de selección. Se estudiaron las variables: grupo etario, factores limitantes de la superación profesional relacionados con los ambientes físico, psicológico, social, familiar y económico. Para el procesamiento de los datos se empleó el paquete estadístico para las ciencias sociales y se expresaron en valores absolutos y porcentajes. Resultados: En el estudio predominó el grupo etario de 20-29 años (29,0 %); condiciones de trabajo inadecuado (33,8 %); presencia de estrés (61,8 %) lo que se sumó la no disponibilidad de desarrollo o promoción (55,5 %) al igual que el bajo nivel retributivo como el principal factor limitante relacionado en la esfera económica (97,4 %). Conclusiones: Los factores que limitaron la formación académica de posgrado en enfermeros incluyen los relacionados con el ambiente físico, psicológico, social, laboral y económico, entre los que se encuentran las condiciones de trabajo inadecuadas, el estrés y el bajo nivel retributivo.

Introduction: Postgraduate academic training is a continuous process of incorporating knowledge, which can have effects due to intrinsic and extrinsic factors. Objective: To determine the limiting factors of nurse postgraduate academic training. Methods: A descriptive observational study was carried out at Camagüey Pediatric Hospital during the 2022 first semester. The universe consisted of 275 nurses and the sample was made up of 272, once the selection criteria were applied. The variables were studied age group, limiting factors of professional improvement related to the physical, psychological, social and family, and economic environments. The Social Science Statistical Package was used to process the data and they were expressed in absolute values and percentages. Results: The age group of 20-29 years predominated in the study (29.0%), with inadequate working conditions (33.8%), presence of stress (61.8%), which added to the lack of availability of development or promotion (55.5%), as well as the low level of remuneration as the main limiting factor related to the economic sphere (97.4%). Conclusions: The factors that limited nurse postgraduate academic training include those related to the physical, psychological, social, work and economic environment, among which are inadequate working conditions, stress and low remuneration.

Fenotipos clínicos en el diagnóstico sicopedagógico de las necesidades educativas especiales

El desarrollo científico tecnológico caracterizado, entre otros por los avances en el campo de las ciencias biomédicas, trascienden a la educación, especialmente se denotan los nexos entre la genética médica y la educación especial. En la provincia de Camagüey se desarrolla una investigación entre los servicios de Genética y el Centro de Diagnóstico y Orientación de la educación especial. A partir del análisis de la interrelación entre ambas ciencias se proyectan en la práctica de la atención de educandos con necesidades educativas especiales enfoques multi, inter y transdisciplinarios con el fin de contribuir al perfeccionamiento del diagnóstico sicopedagógico. El estudio se desarrolla con la colaboración de la Benemérita Universidad Autónoma de Puebla.

Scientific and technological development, characterized among cons by advances in the field of biomedical sciences, transcend education, especially the links between medical genetics and special education. In the province of Camagüey, research is being carried out between the Genetics services and the Diagnosis and Guidance Center for special education. Based on the analysis of the interrelation between both sciences, multi, inter and transdisciplinary approaches are projected into the practice of caring for students with special educational needs, in order to contribute to the improvement of psychopedagogical diagnosis. The study is developed with the collaboration of the Benemérita Universidad Autónoma de Puebla.

Interactions between BRD4S, LOXL2, and MED1 drive cell cycle transcription in triple-negative breast cancer.

Triple-negative breast cancer (TNBC) often develops resistance to single-agent treatment, which can be circumvented using targeted combinatorial approaches. Here, we demonstrate that the simultaneous inhibition of LOXL2 and BRD4 synergistically limits TNBC proliferation in vitro and in vivo. Mechanistically, LOXL2 interacts in the nucleus with the short isoform of BRD4 (BRD4S), MED1, and the cell cycle transcriptional regulator B-MyB. These interactions sustain the formation of BRD4 and MED1 nuclear transcriptional foci and control cell cycle progression at the gene expression level. The pharmacological co-inhibition of LOXL2 and BRD4 reduces BRD4 nuclear foci, BRD4-MED1 colocalization, and the transcription of cell cycle genes, thus suppressing TNBC cell proliferation. Targeting the interaction between BRD4S and LOXL2 could be a starting point for the development of new anticancer strategies for the treatment of TNBC.

Impacto social de la ciencia y la tecnología cubana en el enfrentamiento a la COVID-19 / Social Impact of Cuban Science and Technology the Fight Against COVID-19

Introducción: La ciencia mediante la innovación de los servicios y la tecnología brinda importantes beneficios en función de la sociedad. Objetivo: Proporcionar información sistematizada sobre el impacto social de la ciencia y la tecnología cubana en el enfrentamiento a la COVID-19. Métodos: Se realizó una búsqueda bibliográfica en las bases de datos Scopus, SciELO, ScienceDirect y MEDLINE/PubMed. Para ello, se utilizaron los descriptores o palabras relacionadas con la temática (ciencia, tecnología, COVID-19). Se consultaron artículos de revisión, de posición, y metaanálisis de los años 2020, 2021 y 2022, de la búsqueda solo 30 artículos cumplieron con los criterios de selección. Resultados: En la etapa pandémica, Cuba depositó toda la confianza en sus científicos y sacó provecho a la industria biotecnológica en la búsqueda de salvaguardar la población. Gracias a la satisfactoria gestión del gobierno se obtuvieron resultados positivos en las investigaciones, a partir de la inventiva de los productos como jusvinza, nasalferon, biomodulina T, entre otros. Se inventó un ventilador pulmonar asistido de alta gama para el tratamiento de los adultos, de este modo se fortaleció el trabajo interinstitucional e intersectorial. Conclusiones: La ciencia, la tecnología y las innovaciones han sido cruciales para el manejo de la crisis sanitaria generada por la COVID-19. En Cuba, se obtuvieron valiosos resultados en diferentes niveles para el beneficio de la sociedad; como las vacunas soberana y Abdala(AU)

Introduction: Both science and technology justify their existence through the innovation of services and technologies for the benefit of society. Objective: To provide systematized information on the social impact of Cuban science and technology in the fight against COVID-19. Methods: A bibliographic search was carried out in Scopus, SciELO, ScienceDirect and MEDLINE/PubMed databases. Descriptors or words related to the theme (science, technology, COVID-19) were used. Review articles, position articles, and meta-analyses from 2020, 2021, and 2022 were consulted. Only 30 articles met the selection criteria. Results: In the pandemic stage, Cuba placed all its trust in its scientists and took advantage of the biotechnology industry in the search for the safeguarding of the population. Thanks to the satisfactory management of the government, good results were obtained in the investigations with the inventiveness of products such as Jusvinza, nasalferon, biomodulin T, among others. A high-end assisted lung ventilator was invented for treating adults, in the same way that inter-institutional and intersectoral work was strengthened. Conclusions: Science, technology, and innovations have been crucial in managing the health crisis caused by COVID-19. In Cuba, relevant results have been obtained at different levels for the benefit of society, among which Soberana and Abdala vaccines stand out(AU)

Long-Term Efficacy of High-Dose Imatinib in Hispanic Patients Without Access to Second-Generation Tyrosine Kinase Inhibitors Treated in LATAM Centers.

BACKGROUND: While second-generation tyrosine kinase inhibitors (TKI) revolutionized treatment for patients with chronic myeloid leukemia (CML) who developed a suboptimal response to imatinib, many patients in developing countries are fixed to the latter due to socioeconomic barriers. Despite this scenario, scarce information is available to evaluate the clinical prognosis of these patients. METHODS: We conducted a retrospective cohort analysis to compare the overall mortality of patients with CML who developed a suboptimal response to a standard dose of imatinib and were treated with either high-dose imatinib or a second-generation TKI. We created a marginal structural model with inverse probability weighting and stabilized weights. Our primary outcome was overall survival (OS) at 150 months. Our secondary outcomes were disease-free survival (DFS) at 150 months and adverse events. RESULTS: The cohort included 148 patients, of which 32 received high-dose imatinib and 116 a second-generation TKI. No difference was found in the 150-month overall survival risk (RR: 95% CI 0.91, 0.55-1.95, P-value = .77; RD: -0.04, -0.3 to 0.21, P-value = .78) and disease-free survival (RR: 1.02, 95% CI 0.53-2.71, P-value = .96; RD: 0.01, -0.26 to 0.22, P-value = .96). There was also no difference in the incidence of adverse events in either group. CONCLUSION: Ideally, patients who develop a suboptimal response to imatinib should be switched to a second-generation TKI. If impossible, however, our findings suggest that patients treated with high-dose imatinib have a similar overall survival and disease-free survival prognosis to patients receiving a second-generation TKI.

Infection-related mortality after HLA-identical and haploidentical hematopoietic cell transplantation using reduced-intensity conditioning in an outpatient setting.

BACKGROUND: Despite the improvements in supportive care for allogeneic-hematopoietic cell transplantation (allo-HCT) recipients, infectious complications and infection-related mortality (IRM) continue to be a major issue for transplantation centers. METHODS: We herein report the infectious complications and IRM of 107 and 89 patients that underwent haploidentical (haplo-HCT) or HLA-identical HCT at a tertiary referral center during 2013-2020. Patients in the haplo-HCT group received post-transplant cyclophosphamide (PT-Cy), and all received reduced-intensity conditioning regimens. RESULTS: More haplo-HCT recipients presented severe infections in the pre-engraftment period (22.4% vs. 6.7%, p = 0.003). Viral (14.9% vs. 4.5%, p = 0.016) and fungal (12.1% vs. 1.1%, p = 0.003) etiologies were more common in this period in this group. The 100-day and 2-year cumulative incidence of IRM was 15% and 21% for the haplo-HCT and 5.6% and 17% for the HLA-identical group; no significant differences were observed between the groups. Fungal pathogens mainly contributed to IRM (33.3%). Infections were the most common cause of mortality (40/81, 49.4%). There were significant differences in donor/recipient CMV serostatus between transplant groups (0.002). CONCLUSIONS: No differences in IRM were observed based on allo-HCT type, with more haplo-HCT patients suffering from severe infections in the pre-engraftment period. Studies to assess future prevention, diagnostic, and treatment strategies to reduce IRM are warranted.

Provocative non-canonical roles of p53 and AKT signaling: A role for Thymosin ß4 in medulloblastoma.

The PI3K/AKT and p53 pathways are key regulators of cancer cell survival and death, respectively. Contrary to their generally accepted roles, several lines of evidence, including ours in medulloblastoma, the most common childhood brain cancer, highlight non-canonical functions for both proteins and show a complex context-dependent dynamic behavior in determining cell fate. Interestingly, p53-mediated cell survival and AKT-mediated cell death can dominate in certain conditions, and these interchangeable physiological functions may potentially be manipulated for better clinical outcomes. This review article presents studies in which p53 and AKT behave contrary to their well-established functions. We discuss the factors and circumstances that may be involved in mediating these changes and the implications of these unique roles of p53 and AKT in devising therapeutic strategies. Lastly, based on our recent finding of Thymosin beta 4-mediated chemosensitivity via an AKT-p53 interaction in medulloblastoma cells, we also discuss the possible implications of Thymosin beta-4 in enhancing drug sensitivity in this deadly childhood disease.

Intermittent Soft-Tissue Tumor Enlargement in Episodic Angioedema With Eosinophilia Syndrome.

ABSTRACT: Episodic hypereosinophilia and angioedema syndrome, also known as Gleich syndrome, is a rare entity characterized by recurrent episodes of eosinophilia, angioedema, urticaria, fever and weight gain with spontaneous resolution. It is classified as an idiopathic hypereosinophilic syndrome. Unlike other hypereosinophilic syndromes, it has a low risk for internal organ damage. We report the case of a 42-year-old male with a 28-year history of recurrent erythematous wheals and plaques and persistent hypereosinophilia. Physical examination revealed a well-defined subcutaneous nodule on his right lower limb that increased in size with each episode of angioedema. Histopathology evidenced a lipoma with intense eosinophil infiltration within the mature adipose tissue, while the specimen of the wheal revealed scarce perivascular and interstitial eosinophilic inflammatory infiltrate. Diagnosis of episodic angioedema with eosinophilia syndrome was made based on clinical and laboratory findings.

High p16 expression and heterozygous RB1 loss are biomarkers for CDK4/6 inhibitor resistance in ER+ breast cancer.

CDK4/6 inhibitors combined with endocrine therapy have demonstrated higher antitumor activity than endocrine therapy alone for the treatment of advanced estrogen receptor-positive breast cancer. Some of these tumors are de novo resistant to CDK4/6 inhibitors and others develop acquired resistance. Here, we show that p16 overexpression is associated with reduced antitumor activity of CDK4/6 inhibitors in patient-derived xenografts (n = 37) and estrogen receptor-positive breast cancer cell lines, as well as reduced response of early and advanced breast cancer patients to CDK4/6 inhibitors (n = 89). We also identified heterozygous RB1 loss as biomarker of acquired resistance and poor clinical outcome. Combination of the CDK4/6 inhibitor ribociclib with the PI3K inhibitor alpelisib showed antitumor activity in estrogen receptor-positive non-basal-like breast cancer patient-derived xenografts, independently of PIK3CA, ESR1 or RB1 mutation, also in drug de-escalation experiments or omitting endocrine therapy. Our results offer insights into predicting primary/acquired resistance to CDK4/6 inhibitors and post-progression therapeutic strategies.

Oral N-acetylcysteine decreases IFN-γ production and ameliorates ischemia-reperfusion injury in steatotic livers.

Type 1 Natural Killer T-cells (NKT1 cells) play a critical role in mediating hepatic ischemia-reperfusion injury (IRI). Although hepatic steatosis is a major risk factor for preservation type injury, how NKT cells impact this is understudied. Given NKT1 cell activation by phospholipid ligands recognized presented by CD1d, we hypothesized that NKT1 cells are key modulators of hepatic IRI because of the increased frequency of activating ligands in the setting of hepatic steatosis. We first demonstrate that IRI is exacerbated by a high-fat diet (HFD) in experimental murine models of warm partial ischemia. This is evident in the evaluation of ALT levels and Phasor-Fluorescence Lifetime (Phasor-FLIM) Imaging for glycolytic stress. Polychromatic flow cytometry identified pronounced increases in CD45+CD3+NK1.1+NKT1 cells in HFD fed mice when compared to mice fed a normal diet (ND). This observation is further extended to IRI, measuring ex vivo cytokine expression in the HFD and ND. Much higher interferon-gamma (IFN-γ) expression is noted in the HFD mice after IRI. We further tested our hypothesis by performing a lipidomic analysis of hepatic tissue and compared this to Phasor-FLIM imaging using "long lifetime species", a byproduct of lipid oxidation. There are higher levels of triacylglycerols and phospholipids in HFD mice. Since N-acetylcysteine (NAC) is able to limit hepatic steatosis, we tested how oral NAC supplementation in HFD mice impacted IRI. Interestingly, oral NAC supplementation in HFD mice results in improved hepatic enhancement using contrast-enhanced magnetic resonance imaging (MRI) compared to HFD control mice and normalization of glycolysis demonstrated by Phasor-FLIM imaging. This correlated with improved biochemical serum levels and a decrease in IFN-γ expression at a tissue level and from CD45+CD3+CD1d+ cells. Lipidomic evaluation of tissue in the HFD+NAC mice demonstrated a drastic decrease in triacylglycerol, suggesting downregulation of the PPAR-γ pathway.

Treatment of Ph-Negative Acute Lymphoblastic Leukemia in Adolescents and Young Adults with an Affordable Outpatient Pediatric Regimen.

BACKGROUND: B-cell acute lymphoblastic leukemia is frequent in Hispanic adolescents and young adults. Outcomes of implementation of pediatric-inspired regimens in low-and middle-income countries are not well known. METHODS: In this study we treated 94 adolescents and young adults with a local BFM regimen designed to be affordable with the use of native L-asparaginase and mitoxantrone administered in an outpatient fashion, and the of BCR/ABL and measurable residual disease (MRD) determined by high sensitivity flow cytometry for risk stratification. RESULTS: Induction mortality was 11%; 25% of patients had to abandon treatment or be transferred to another health system. Two-year overall (OS) and event free survival (EFS) were 61.5% and 49.8%, MRD-negative patients had a 24-month OS of 85.6% vs. 69.6% (p = .024) and EFS of 76% vs. 45.5% (p = .004). Patients older than 40 years and those who abandoned treatment had worse EFS. Overall drug costs in our regimen were 52% lower than those of CALGB10403. CONCLUSION: The treatment of AYAs with ALL with an outpatient focus was implemented successfully at a reduced cost. Genetic risk assessment, treatment abandonment and lack of access to novel therapies remain major barriers for improving outcomes.

Identification of a Molecularly-Defined Subset of Breast and Ovarian Cancer Models that Respond to WEE1 or ATR Inhibition, Overcoming PARP Inhibitor Resistance.

PURPOSE: PARP inhibitors (PARPi) induce synthetic lethality in homologous recombination repair (HRR)-deficient tumors and are used to treat breast, ovarian, pancreatic, and prostate cancers. Multiple PARPi resistance mechanisms exist, most resulting in restoration of HRR and protection of stalled replication forks. ATR inhibition was highlighted as a unique approach to reverse both aspects of resistance. Recently, however, a PARPi/WEE1 inhibitor (WEE1i) combination demonstrated enhanced antitumor activity associated with the induction of replication stress, suggesting another approach to tackling PARPi resistance. EXPERIMENTAL DESIGN: We analyzed breast and ovarian patient-derived xenoimplant models resistant to PARPi to quantify WEE1i and ATR inhibitor (ATRi) responses as single agents and in combination with PARPi. Biomarker analysis was conducted at the genetic and protein level. Metabolite analysis by mass spectrometry and nucleoside rescue experiments ex vivo were also conducted in patient-derived models. RESULTS: Although WEE1i response was linked to markers of replication stress, including STK11/RB1 and phospho-RPA, ATRi response associated with ATM mutation. When combined with olaparib, WEE1i could be differentiated from the ATRi/olaparib combination, providing distinct therapeutic strategies to overcome PARPi resistance by targeting the replication stress response. Mechanistically, WEE1i sensitivity was associated with shortage of the dNTP pool and a concomitant increase in replication stress. CONCLUSIONS: Targeting the replication stress response is a valid therapeutic option to overcome PARPi resistance including tumors without an underlying HRR deficiency. These preclinical insights are now being tested in several clinical trials where the PARPi is administered with either the WEE1i or the ATRi.

EphB4 and ephrinB2 act in opposition in the head and neck tumor microenvironment.

Differential outcomes of EphB4-ephrinB2 signaling offers formidable challenge for the development of cancer therapeutics. Here, we interrogate the effects of targeting EphB4 and ephrinB2 in head and neck squamous cell carcinoma (HNSCC) and within its microenvironment using genetically engineered mice, recombinant constructs, pharmacologic agonists and antagonists. We observe that manipulating the EphB4 intracellular domain on cancer cells accelerates tumor growth and angiogenesis. EphB4 cancer cell loss also triggers compensatory upregulation of EphA4 and T regulatory cells (Tregs) influx and their targeting results in reversal of accelerated tumor growth mediated by EphB4 knockdown. EphrinB2 knockout on cancer cells and vasculature, on the other hand, results in maximal tumor reduction and vascular normalization. We report that EphB4 agonism provides no additional anti-tumoral benefit in the absence of ephrinB2. These results identify ephrinB2 as a tumor promoter and its receptor, EphB4, as a tumor suppressor in HNSCC, presenting opportunities for rational drug design.