Chromothriptic cure of WHIM syndrome.

Chromothripsis is a catastrophic cellular event recently described in cancer in which chromosomes undergo massive deletion and rearrangement. Here, we report a case in which chromothripsis spontaneously cured a patient with WHIM syndrome, an autosomal dominant combined immunodeficiency disease caused by gain-of-function mutation of the chemokine receptor CXCR4. In this patient, deletion of the disease allele, CXCR4(R334X), as well as 163 other genes from one copy of chromosome 2 occurred in a hematopoietic stem cell (HSC) that repopulated the myeloid but not the lymphoid lineage. In competitive mouse bone marrow (BM) transplantation experiments, Cxcr4 haploinsufficiency was sufficient to confer a strong long-term engraftment advantage of donor BM over BM from either wild-type or WHIM syndrome model mice, suggesting a potential mechanism for the patient's cure. Our findings suggest that partial inactivation of CXCR4 may have general utility as a strategy to promote HSC engraftment in transplantation.

An interdisciplinary consensus on the management of brain metastases in patients with renal cell carcinoma.

Brain metastases are a challenging manifestation of renal cell carcinoma. We have a limited understanding of brain metastasis tumor and immune biology, drivers of resistance to systemic treatment, and their overall poor prognosis. Current data support a multimodal treatment strategy with radiation treatment and/or surgery. Nonetheless, the optimal approach for the management of brain metastases from renal cell carcinoma remains unclear. To improve patient care, the authors sought to standardize practical management strategies. They performed an unstructured literature review and elaborated on the current management strategies through an international group of experts from different disciplines assembled via the network of the International Kidney Cancer Coalition. Experts from different disciplines were administered a survey to answer questions related to current challenges and unmet patient needs. On the basis of the integrated approach of literature review and survey study results, the authors built algorithms for the management of single and multiple brain metastases in patients with renal cell carcinoma. The literature review, consensus statements, and algorithms presented in this report can serve as a framework guiding treatment decisions for patients. CA Cancer J Clin. 2022;72:454-489.

Overall Survival with Adjuvant Pembrolizumab in Renal-Cell Carcinoma.

BACKGROUND: Adjuvant pembrolizumab therapy after surgery for renal-cell carcinoma was approved on the basis of a significant improvement in disease-free survival in the KEYNOTE-564 trial. Whether the results regarding overall survival from the third prespecified interim analysis of the trial would also favor pembrolizumab was uncertain. METHODS: In this phase 3, double-blind, placebo-controlled trial, we randomly assigned (in a 1:1 ratio) participants with clear-cell renal-cell carcinoma who had an increased risk of recurrence after surgery to receive pembrolizumab (at a dose of 200 mg) or placebo every 3 weeks for up to 17 cycles (approximately 1 year) or until recurrence, the occurrence of unacceptable toxic effects, or withdrawal of consent. A significant improvement in disease-free survival according to investigator assessment (the primary end point) was shown previously. Overall survival was the key secondary end point. Safety was a secondary end point. RESULTS: A total of 496 participants were assigned to receive pembrolizumab and 498 to receive placebo. As of September 15, 2023, the median follow-up was 57.2 months. The disease-free survival benefit was consistent with that in previous analyses (hazard ratio for recurrence or death, 0.72; 95% confidence interval [CI], 0.59 to 0.87). A significant improvement in overall survival was observed with pembrolizumab as compared with placebo (hazard ratio for death, 0.62; 95% CI, 0.44 to 0.87; P = 0.005). The estimated overall survival at 48 months was 91.2% in the pembrolizumab group, as compared with 86.0% in the placebo group; the benefit was consistent across key subgroups. Pembrolizumab was associated with a higher incidence of serious adverse events of any cause (20.7%, vs. 11.5% with placebo) and of grade 3 or 4 adverse events related to pembrolizumab or placebo (18.6% vs. 1.2%). No deaths were attributed to pembrolizumab therapy. CONCLUSIONS: Adjuvant pembrolizumab was associated with a significant and clinically meaningful improvement in overall survival, as compared with placebo, among participants with clear-cell renal-cell carcinoma at increased risk for recurrence after surgery. (Funded by Merck Sharp and Dohme, a subsidiary of Merck; KEYNOTE-564 ClinicalTrials.gov number, NCT03142334.).

CRISPR/Cas9-mediated Cxcr4 disease allele inactivation for gene therapy in a mouse model of WHIM syndrome.

WHIM syndrome is an autosomal dominant immunodeficiency disorder caused by gain-of-function mutations in chemokine receptor CXCR4 that promote severe panleukopenia because of retention of mature leukocytes in the bone marrow (BM). We previously reported that Cxcr4-haploinsufficient (Cxcr4+/o) hematopoietic stem cells (HSCs) have a strong selective advantage for durable hematopoietic reconstitution over wild-type (Cxcr4+/+) and WHIM (Cxcr4+/w) HSCs and that a patient with WHIM was spontaneously cured by chromothriptic deletion of the disease allele in an HSC, suggesting that WHIM allele inactivation through gene editing may be a safe genetic cure strategy for the disease. We have developed a 2-step preclinical protocol of autologous hematopoietic stem and progenitor cell (HSPC) transplantation to achieve this goal. First, 1 copy of Cxcr4 in HSPCs was inactivated in vitro by CRISPR/Cas9 editing with a single guide RNA (sgRNA) that does not discriminate between Cxcr4+/w and Cxcr4+/+ alleles. Then, through in vivo natural selection, WHIM allele-inactivated cells were enriched over wild-type allele-inactivated cells. The WHIM allele-inactivated HSCs retained long-term pluripotency and selective hematopoietic reconstitution advantages. To our knowledge, this is the first example of gene therapy for an autosomal dominant gain-of-function disease using a disease allele inactivation strategy in place of the less efficient disease allele repair approach.

Severe CD8+ T Lymphopenia in WHIM Syndrome Caused by Selective Sequestration in Primary Immune Organs.

Warts, hypogammaglobulinemia, infections, and myelokathexis (WHIM) syndrome is an ultra-rare combined primary immunodeficiency disease caused by heterozygous gain-of-function mutations in the chemokine receptor CXCR4. WHIM patients typically present with recurrent acute infections associated with myelokathexis (severe neutropenia due to bone marrow retention of mature neutrophils). Severe lymphopenia is also common, but the only associated chronic opportunistic pathogen is human papillomavirus and mechanisms are not clearly defined. In this study, we show that WHIM mutations cause more severe CD8 than CD4 lymphopenia in WHIM patients and WHIM model mice. Mechanistic studies in mice revealed selective and WHIM allele dose-dependent accumulation of mature CD8 single-positive cells in thymus in a cell-intrinsic manner due to prolonged intrathymic residence, associated with increased CD8 single-positive thymocyte chemotactic responses in vitro toward the CXCR4 ligand CXCL12. In addition, mature WHIM CD8+ T cells preferentially home to and are retained in the bone marrow in mice in a cell-intrinsic manner. Administration of the specific CXCR4 antagonist AMD3100 (plerixafor) in mice rapidly and transiently corrected T cell lymphopenia and the CD4/CD8 ratio. After lymphocytic choriomeningitis virus infection, we found no difference in memory CD8+ T cell differentiation or viral load between wild-type and WHIM model mice. Thus, lymphopenia in WHIM syndrome may involve severe CXCR4-dependent CD8+ T cell deficiency resulting in part from sequestration in the primary lymphoid organs, thymus, and bone marrow.

Perturbations of the T-cell receptor repertoire in response to SARS-CoV-2 in immunocompetent and immunocompromised individuals.

BACKGROUND: Functional T-cell responses are essential for virus clearance and long-term protection after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, whereas certain clinical factors, such as older age and immunocompromise, are associated with worse outcome. OBJECTIVE: We sought to study the breadth and magnitude of T-cell responses in patients with coronavirus disease 2019 (COVID-19) and in individuals with inborn errors of immunity (IEIs) who had received COVID-19 mRNA vaccine. METHODS: Using high-throughput sequencing and bioinformatics tools to characterize the T-cell receptor ß repertoire signatures in 540 individuals after SARS-CoV-2 infection, 31 IEI recipients of COVID-19 mRNA vaccine, and healthy controls, we quantified HLA class I- and class II-restricted SARS-CoV-2-specific responses and also identified several HLA allele-clonotype motif associations in patients with COVID-19, including a subcohort of anti-type 1 interferon (IFN-1)-positive patients. RESULTS: Our analysis revealed that elderly patients with COVID-19 with critical disease manifested lower SARS-CoV-2 T-cell clonotype diversity as well as T-cell responses with reduced magnitude, whereas the SARS-CoV-2-specific clonotypes targeted a broad range of HLA class I- and class II-restricted epitopes across the viral proteome. The presence of anti-IFN-I antibodies was associated with certain HLA alleles. Finally, COVID-19 mRNA immunization induced an increase in the breadth of SARS-CoV-2-specific clonotypes in patients with IEIs, including those who had failed to seroconvert. CONCLUSIONS: Elderly individuals have impaired capacity to develop broad and sustained T-cell responses after SARS-CoV-2 infection. Genetic factors may play a role in the production of anti-IFN-1 antibodies. COVID-19 mRNA vaccines are effective in inducing T-cell responses in patients with IEIs.

Perioperative nivolumab versus observation in patients with renal cell carcinoma undergoing nephrectomy (PROSPER ECOG-ACRIN EA8143): an open-label, randomised, phase 3 study.

BACKGROUND: The standard of care for patients with intermediate-to-high risk renal cell carcinoma is partial or radical nephrectomy followed by surveillance. We aimed to investigate use of nivolumab before nephrectomy followed by adjuvant nivolumab in patients with high-risk renal cell carcinoma to determine recurrence-free survival compared with surgery only. METHODS: In this open-label, randomised, phase 3 trial (PROSPER EA8143), patients were recruited from 183 community and academic sites across the USA and Canada. Eligible patients were aged 18 years or older with an Eastern Cooperative Oncology Group performance status of 0-1, with previously untreated clinical stage T2 or greater or Tany N+ renal cell carcinoma of clear cell or non-clear cell histology planned for partial or radical nephrectomy. Selected patients with oligometastatic disease, who were disease free at other disease sites within 12 weeks of surgery, were eligible for inclusion. We randomly assigned (1:1) patients using permuted blocks (block size of 4) within stratum (clinical TNM stage) to either nivolumab plus surgery, or surgery only followed by surveillance. In the nivolumab group, nivolumab 480 mg was administered before surgery, followed by nine adjuvant doses. The primary endpoint was investigator-reviewed recurrence-free survival in patients with renal cell carcinoma assessed in all randomly assigned patients regardless of histology. Safety was assessed in all randomly assigned patients who started the assigned protocol treatment. This trial is registered with ClinicalTrials.gov, NCT03055013, and is closed to accrual. FINDINGS: Between Feb 2, 2017, and June 2, 2021, 819 patients were randomly assigned to nivolumab plus surgery (404 [49%]) or surgery only (415 [51%]). 366 (91%) of 404 patients assigned to nivolumab plus surgery and 387 (93%) of 415 patients assigned to surgery only group started treatment. Median age was 61 years (IQR 53-69), 248 (30%) of 819 patients were female, 571 (70%) were male, 672 (88%) were White, and 77 (10%) were Hispanic or Latino. The Data and Safety Monitoring Committee stopped the trial at a planned interim analysis (March 25, 2022) because of futility. Median follow-up was 30·4 months (IQR 21·5-42·4) in the nivolumab group and 30·1 months (21·9-41·8) in the surgery only group. 381 (94%) of 404 patients in the nivolumab plus surgery group and 399 (96%) of 415 in the surgery only group had renal cell carcinoma and were included in the recurrence-free survival analysis. As of data cutoff (May 24, 2023), recurrence-free survival was not significantly different between nivolumab (125 [33%] of 381 had recurrence-free survival events) versus surgery only (133 [33%] of 399; hazard ratio 0·94 [95% CI 0·74-1·21]; one-sided p=0·32). The most common treatment-related grade 3-4 adverse events were elevated lipase (17 [5%] of 366 patients in the nivolumab plus surgery group vs none in the surgery only group), anaemia (seven [2%] vs nine [2%]), increased alanine aminotransferase (ten [3%] vs one [<1%]), abdominal pain (four [1%] vs six [2%]), and increased serum amylase (nine [2%] vs none). 177 (48%) patients in the nivolumab plus surgery group and 93 (24%) in the surgery only group had grade 3-5 adverse events due to any cause, the most common of which were anaemia (23 [6%] vs 19 [5%]), hypertension (27 [7%] vs nine [2%]), and elevated lipase (18 [5%] vs six [2%]). 48 (12%) of 404 patients in the nivolumab group and 40 (10%) of 415 in the surgery only group died, of which eight (2%) and three (1%), respectively, were determined to be treatment-related. INTERPRETATION: Perioperative nivolumab before nephrectomy followed by adjuvant nivolumab did not improve recurrence-free survival versus surgery only followed by surveillance in patients with high-risk renal cell carcinoma. FUNDING: US National Institutes of Health National Cancer Institute and Bristol Myers Squibb.

Long-Term Survival in Patients With Relapsed/Refractory Advanced Renal Cell Carcinoma Treated With Tivozanib: Analysis of the Phase III TIVO-3 Trial.

BACKGROUND: Tivozanib is an oral vascular endothelial growth factor receptor (VEGFR) tyrosine kinase inhibitor (TKI) with efficacy in advanced renal cell carcinoma (RCC). Long-term exploratory analyses from the TIVO-3 trial in relapsed/refractory (R/R) RCC including patients (26%) with prior immuno-oncology (IO) therapy are reported. METHODS: Patients with R/R advanced RCC that progressed with 2 or 3 prior systemic therapies (≥1 VEGFR TKI) were randomized to tivozanib 1.5 mg QD or sorafenib 400 mg BID, stratified by IMDC risk and previous therapy. Safety, investigator-assessed long-term progression-free survival (LT-PFS), and serial overall survival (OS) were assessed. RESULTS: Mean time on treatment was 11.0 months with tivozanib (n = 175) and 6.3 months with sorafenib (n = 175). Fewer grade ≥3 treatment-related adverse events occurred with tivozanib (46%) than sorafenib (55%). Dose modification rates were lower with tivozanib than sorafenib across age/prior IO subgroups; prior IO therapy did not impact dose reductions or discontinuations in either arm. Landmark LT-PFS rates were higher with tivozanib (3 years: 12.3% vs 2.4%; 4 years: 7.6% vs 0%). After 22.8 months mean follow-up, the OS HR was 0.89 (95% CI, 0.70-1.14); when conditioned on 12-month landmark PFS, tivozanib showed significant OS improvement over sorafenib (HR, 0.45; 95% CI, 0.22-0.91; 2-sided P = .0221). CONCLUSIONS: Tivozanib demonstrated a consistent safety profile and long-term survival benefit in patients with R/R advanced RCC who were alive and progression free at 12 months. These post hoc exploratory analyses of LT-PFS and conditional OS support a clinically meaningful improvement with tivozanib versus sorafenib in this advanced RCC population.

Periodontal disease in patients with WHIM syndrome.

AIM: WHIM (warts, hypogammaglobulinaemia, infections and myelokathexis) syndrome is a rare combined primary immunodeficiency disease caused by gain-of-function (GOF) mutations in the chemokine receptor CXCR4 and includes severe neutropenia as a common feature. Neutropenia is a known risk factor for periodontitis; however, a detailed periodontal evaluation of a WHIM syndrome cohort is lacking. This study aimed to establish the evidence base for the periodontal status of patients with WHIM syndrome. MATERIALS AND METHODS: Twenty-two adult WHIM syndrome patients and 22 age- and gender-matched healthy volunteers (HVs) were evaluated through a comprehensive medical and periodontal examination. A mouse model of WHIM syndrome was assessed for susceptibility to naturally progressing or inducible periodontitis. RESULTS: Fourteen patients with WHIM syndrome (63.6%) and one HV (4.5%) were diagnosed with Stage III/IV periodontitis. No WHIM patient presented with the early onset, dramatic clinical phenotypes typically associated with genetic forms of neutropenia. Age, but not the specific CXCR4 mutation or absolute neutrophil count, was associated with periodontitis severity in the WHIM cohort. Mice with a Cxcr4 GOF mutation did not exhibit increased alveolar bone loss in spontaneous or ligature-induced periodontitis. CONCLUSIONS: Overall, WHIM syndrome patients presented with an increased severity of periodontitis despite past and ongoing neutrophil mobilization treatments. GOF mutations in CXCR4 may be a risk factor for periodontitis in humans.

Belzutifan plus cabozantinib for patients with advanced clear cell renal cell carcinoma previously treated with immunotherapy: an open-label, single-arm, phase 2 study.

BACKGROUND: Few treatment options are available for patients with advanced renal cell carcinoma who have received previous anti-PD-1-based or anti-PD-L1-based immunotherapy. Combining belzutifan, an HIF-2α inhibitor, with cabozantinib, a multitargeted tyrosine-kinase inhibitor of VEGFR, c-MET, and AXL, might provide more antitumoural effects than either agent alone. We aimed to investigate the antitumour activity and safety of belzutifan plus cabozantinib in patients with advanced clear cell renal cell carcinoma that was previously treated with immunotherapy. METHODS: This open-label, single-arm, phase 2 study was conducted at ten hospitals and cancer centres in the USA. Patients were enrolled into two cohorts. Patients in cohort 1 had treatment-naive disease (results will be reported separately). In cohort 2, eligible patients were aged 18 years or older with locally advanced or metastatic clear cell renal cell carcinoma, measurable disease according to Response Evaluation Criteria in Solid Tumours version 1.1, an Eastern Cooperative Oncology Group performance status score of 0 or 1, and had previously received immunotherapy and up to two systemic treatment regimens. Patients were given belzutifan 120 mg orally once daily and cabozantinib 60 mg orally once daily until disease progression, unacceptable toxicity, or patient withdrawal. The primary endpoint was confirmed objective response assessed by the investigator. Antitumour activity and safety were assessed in all patients who received at least one dose of study treatment. This trial is registered with ClinicalTrials.gov, NCT03634540, and is ongoing. FINDINGS: Between Sept 27, 2018, and July 14, 2020, 117 patients were screened for eligibility, 52 (44%) of whom were enrolled in cohort 2 and received at least one dose of study treatment. Median age was 63·0 years (IQR 57·5-68·5), 38 (73%) of 52 patients were male, 14 (27%) were female, 48 (92%) were White, two (4%) were Black or African American, and two were Asian (4%). As of data cutoff (Feb 1, 2022), median follow-up was 24·6 months (IQR 22·1-32·2). 16 (30·8% [95% CI 18·7-45·1]) of 52 patients had a confirmed objective response, including one (2%) who had a complete response and 15 (29%) who had partial responses. The most common grade 3-4 treatment-related adverse event was hypertension (14 [27%] of 52 patients). Serious treatment-related adverse events occurred in 15 (29%) patients. One death was considered treatment related by the investigator (respiratory failure). INTERPRETATION: Belzutifan plus cabozantinib has promising antitumour activity in patients with pretreated clear cell renal cell carcinoma and our findings provide rationale for further randomised trials with belzutifan in combination with a VEGFR tyrosine-kinase inhibitor. FUNDING: Merck Sharp & Dohme (a subsidiary of Merck & Co) and the National Cancer Institute.

Tivozanib in Patients with Advanced Renal Cell Carcinoma Previously Treated With Axitinib: Subgroup Analysis from TIVO-3.

BACKGROUND: In phase III TIVO-3 trial, tivozanib improved progression-free survival (PFS) compared to sorafenib for patients with metastatic renal cell carcinoma (mRCC). However, the effectiveness of this drug after exposure to other selective VEGFR agents has not yet been defined. Herein, we characterize the clinical efficacy of tivozanib in patients with mRCC previously treated with axitinib. METHODS: We identified patients from the intention to treat (ITT) population, in the TIVO-3 trial, who received treatment with axitinib before enrolment in the study and evaluated PFS, response rate (RR), and safety. RESULTS: Out of 350 patients, 172 (83:89, tivozanib:sorafenib) had received prior treatment with axitinib in TIVO-3. In this subgroup, PFS was 5.5 months with tivozanib and 3.7 months with sorafenib (HR 0.68). RR was 13% and 8% favoring tivozanib. CONCLUSIONS: Tivozanib is active in the treatment of patients with mRCC who have progressed on prior therapies, including axitinib.

Avelumab Plus Axitinib as First-Line Therapy for Advanced Renal Cell Carcinoma: Long-Term Results from the JAVELIN Renal 100 Phase Ib Trial.

BACKGROUND: Progression-free survival was significantly longer in patients who received avelumab plus axitinib versus sunitinib as first-line treatment for advanced renal cell carcinoma (aRCC) in a randomized phase III trial. We report long-term safety and efficacy of avelumab plus axitinib as first-line treatment for patients with aRCC from the JAVELIN Renal 100 phase Ib trial (NCT02493751). MATERIALS AND METHODS: In this open-label, multicenter, phase Ib study, patients with untreated aRCC received avelumab 10 mg/kg every 2 weeks plus axitinib 5 mg twice daily or with axitinib for 7 days followed by avelumab plus axitinib. Safety and efficacy were assessed in all patients receiving at least one dose of avelumab or axitinib. RESULTS: Overall, 55 patients were enrolled and treated. Median follow-up was 55.7 months (95% CI, 54.5-58.7). Treatment-related adverse events of any grade or grade ≥3 occurred in 54 (98.2%) and 34 (61.8%) patients, respectively. The confirmed objective response rate was 60.0% (95% CI, 45.9-73.0), including complete response in 10.9% of patients. Median duration of response was 35.9 months (95% CI, 12.7-52.9); the probability of response was 65.8% (95% CI, 46.7-79.4) at 2 years. Median progression-free survival was 8.3 months (95% CI, 5.3-32.0). Median overall survival was not reached (95% CI, 40.8-not estimable); the 5-year overall survival rate was 57.3% (95% CI, 41.2-70.5). CONCLUSION: Five-year follow-up for combination treatment with avelumab plus axitinib in previously untreated patients with aRCC showed long-term clinical activity with no new safety signals, supporting use of this regimen within its approved indication in clinical practice (Clinicaltrials.gov NCT02493751).

Hematologic disorder-associated Cxcr4 gain-of-function mutation leads to uncontrolled extrafollicular immune response.

The extrafollicular immune response is essential to generate a rapid but transient wave of protective antibodies during infection. Despite its importance, the molecular mechanisms controlling this first response are poorly understood. Here, we demonstrate that enhanced Cxcr4 signaling caused by defective receptor desensitization leads to exacerbated extrafollicular B-cell response. Using a mouse model bearing a gain-of-function mutation of Cxcr4 described in 2 human hematologic disorders, warts, hypogammaglobulinemia, infections, and myelokathexis (WHIM) syndrome and Waldenström macroglobulinemia, we demonstrated that mutant B cells exhibited enhanced mechanistic target of rapamycin signaling, cycled more, and differentiated more potently into plasma cells than wild-type B cells after Toll-like receptor (TLR) stimulation. Moreover, Cxcr4 gain of function promoted enhanced homing and persistence of immature plasma cells in the bone marrow, a phenomenon recapitulated in WHIM syndrome patient samples. This translated in increased and more sustained production of antibodies after T-independent immunization in Cxcr4 mutant mice. Thus, our results establish that fine-tuning of Cxcr4 signaling is essential to limit the strength and length of the extrafollicular immune response.

SASH3 variants cause a novel form of X-linked combined immunodeficiency with immune dysregulation.

Sterile alpha motif (SAM) and Src homology-3 (SH3) domain-containing 3 (SASH3), also called SH3-containing lymphocyte protein (SLY1), is a putative adaptor protein that is postulated to play an important role in the organization of signaling complexes and propagation of signal transduction cascades in lymphocytes. The SASH3 gene is located on the X-chromosome. Here, we identified 3 novel SASH3 deleterious variants in 4 unrelated male patients with a history of combined immunodeficiency and immune dysregulation that manifested as recurrent sinopulmonary, cutaneous, and mucosal infections and refractory autoimmune cytopenias. Patients exhibited CD4+ T-cell lymphopenia, decreased T-cell proliferation, cell cycle progression, and increased T-cell apoptosis in response to mitogens. In vitro T-cell differentiation of CD34+ cells and molecular signatures of rearrangements at the T-cell receptor α (TRA) locus were indicative of impaired thymocyte survival. These patients also manifested neutropenia and B-cell and natural killer (NK)-cell lymphopenia. Lentivirus-mediated transfer of the SASH3 complementary DNA-corrected protein expression, in vitro proliferation, and signaling in SASH3-deficient Jurkat and patient-derived T cells. These findings define a new type of X-linked combined immunodeficiency in humans that recapitulates many of the abnormalities reported in mice with Sly1-/- and Sly1Δ/Δ mutations, highlighting an important role of SASH3 in human lymphocyte function and survival.

Regulation of HHLA2 expression in kidney cancer and myeloid cells.

BACKGROUND: The immune checkpoint HERV-H LTR-associating 2 (HHLA2) is expressed in kidney cancer and various other tumor types. Therapeutics targeting HHLA2 or its inhibitory receptor KIR3DL3 are being developed for solid tumors, including renal cell carcinoma (RCC). However, the regulation of HHLA2 expression remains poorly understood. A better understanding of HHLA2 regulation in tumor cells and the tumor microenvironment is crucial for the successful translation of these therapeutic agents into clinical applications. METHODS: Flow cytometry and quantitative real-time PCR were used to analyze HHLA2 expression in primary kidney tumors ex vivo and during in vitro culture. HHLA2 expression in A498 and 786-O ccRCC cell lines was examined in vitro and in subcutaneous tumor xenografts in NSG mice. Monocytes and dendritic cells were analyzed for HHLA2 expression. We tested a range of cytokines and culture conditions, including hypoxia, to induce HHLA2 expression. RESULTS: Analysis of HHLA2 expression revealed that HHLA2 is expressed on tumor cells in primary kidney tumors ex vivo; however, its expression gradually diminishes during a 4-week in vitro culture period. A498 and 786-O ccRCC tumor cell lines do not express HHLA2 in vitro, but HHLA2 expression was observed when grown as subcutaneous xenografts in NSG immunodeficient mice. Induction experiments using various cytokines and culture conditions failed to induce HHLA2 expression in A498 and 786-O tumor cell lines in vitro. Analysis of HHLA2 expression in monocytes and dendritic cells demonstrated that only IL-10 and BMP4, along with IL-1ß and IL-6 to a lesser extent, modestly enhanced HHLA2 protein and mRNA expression. CONCLUSIONS: HHLA2 expression is induced on kidney cancer cells in vivo by a tumor microenvironmental signal that is not present in vitro. HHLA2 expression is differentially regulated in kidney cancer epithelial cells and monocytes. Cytokines, particularly IL10, that induce HHLA2 expression in monocytes fail to upregulate HHLA2 expression in tumor cell lines in vitro. These findings underscore the importance of the interplay between tumor cell and tumor microenvironmental signals in the regulation of HHLA2. Further investigation is warranted to elucidate the mechanisms involved in HHLA2 regulation and its implications for therapeutic development.

WHIM syndrome: Immunopathogenesis, treatment and cure strategies.

WHIM syndrome is a rare, autosomal dominant immunodeficiency which is named for the four key manifestations: Warts, Hypogammaglobulinemia, Infections, and Myelokathexis. It results from heterozygous gain-of-function mutations in the chemokine receptor CXCR4 which is widely expressed on leukocytes and has profound influences on immune system homeostasis and organogenesis. New treatments for the disease using drugs to reduce CXCR4 function are excellent examples of precision medicine. Since CXCR4 and its ligand CXCL12 play an important role in a variety of infectious, inflammatory, autoimmune, and malignant diseases, the study of WHIM syndrome provides important insights into both the physiologic and disease roles of these molecules.

Conditional survival and long-term efficacy with nivolumab plus ipilimumab versus sunitinib in patients with advanced renal cell carcinoma.

BACKGROUND: Conditional survival estimates provide critical prognostic information for patients with advanced renal cell carcinoma (aRCC). Efficacy, safety, and conditional survival outcomes were assessed in CheckMate 214 (ClinicalTrials.gov identifier NCT02231749) with a minimum follow-up of 5 years. METHODS: Patients with untreated aRCC were randomized to receive nivolumab (NIVO) (3 mg/kg) plus ipilimumab (IPI) (1 mg/kg) every 3 weeks for 4 cycles, then either NIVO monotherapy or sunitinib (SUN) (50 mg) daily (four 6-week cycles). Efficacy was assessed in intent-to-treat, International Metastatic Renal Cell Carcinoma Database Consortium intermediate-risk/poor-risk, and favorable-risk populations. Conditional survival outcomes (the probability of remaining alive, progression free, or in response 2 years beyond a specified landmark) were analyzed. RESULTS: The median follow-up was 67.7 months; overall survival (median, 55.7 vs 38.4 months; hazard ratio, 0.72), progression-free survival (median, 12.3 vs 12.3 months; hazard ratio, 0.86), and objective response (39.3% vs 32.4%) benefits were maintained with NIVO+IPI versus SUN, respectively, in intent-to-treat patients (N = 550 vs 546). Point estimates for 2-year conditional overall survival beyond the 3-year landmark were higher with NIVO+IPI versus SUN (intent-to-treat patients, 81% vs 72%; intermediate-risk/poor-risk patients, 79% vs 72%; favorable-risk patients, 85% vs 72%). Conditional progression-free survival and response point estimates were also higher beyond 3 years with NIVO+IPI. Point estimates for conditional overall survival were higher or remained steady at each subsequent year of survival with NIVO+IPI in patients stratified by tumor programmed death ligand 1 expression, grade ≥3 immune-mediated adverse event experience, body mass index, and age. CONCLUSIONS: Durable clinical benefits were observed with NIVO+IPI versus SUN at 5 years, the longest phase 3 follow-up for a first-line checkpoint inhibitor-based combination in patients with aRCC. Conditional estimates indicate that most patients who remained alive or in response with NIVO+IPI at 3 years remained so at 5 years.

Multicenter Experience of Hematopoietic Stem Cell Transplantation in WHIM Syndrome.

PURPOSE: WHIM (warts, hypogammaglobulinemia, infections, and myelokathexis) syndrome is a rare disease, caused by CXCR4 gene mutations, which incorporates features of combined immunodeficiency, congenital neutropenia, and a predisposition to human papillomavirus infection. Established conventional treatment for WHIM syndrome does not fully prevent infectious complications in these patients. Only single case reports of hematopoietic stem cell transplantation (HSCT) efficacy in WHIM have been published. METHODS: To summarize current information on HSCT efficacy in disease treatment, seven pediatric patients with WHIM syndrome who underwent allogeneic HSCT were identified in five centers worldwide. RESULTS: All patients presented early after birth with neutropenia. Two of seven patients exhibited severe disease complications: poorly controlled autoimmunity (arthritis and anemia) in one and progressive myelofibrosis with recurrent infections in the other. The remaining patients received HSCT to correct milder disease symptoms (recurrent respiratory infections, progressing thrombocytopenia) and/or to preclude severe disease course in older age. All seven patients engrafted but one developed graft rejection and died of infectious complications after third HSCT. Three other patients experienced severe viral infections after HSCT (including post-transplant lymphoproliferative disease in one) which completely resolved with therapy. At last follow-up (median 6.7 years), all six surviving patients were alive with full donor chimerism. One patient 1.4 years after HSCT had moderate thrombocytopenia and delayed immune recovery; the others had adequate immune recovery and were free of prior disease symptoms. CONCLUSION: HSCT in WHIM syndrome corrects neutropenia and immunodeficiency, and leads to resolution of autoimmunity and recurrent infections, including warts.

Plerixafor for the Treatment of WHIM Syndrome.

WHIM syndrome (warts, hypogammaglobulinemia, infections, and myelokathexis), a primary immunodeficiency disorder involving panleukopenia, is caused by autosomal dominant gain-of-function mutations in CXC chemokine receptor 4 (CXCR4). Myelokathexis is neutropenia caused by neutrophil retention in bone marrow. Patients with WHIM syndrome are often treated with granulocyte colony-stimulating factor (G-CSF), which can increase neutrophil counts but does not affect cytopenias other than neutropenia. In this investigator-initiated, open-label study, three severely affected patients with WHIM syndrome who could not receive G-CSF were treated with low-dose plerixafor, a CXCR4 antagonist, for 19 to 52 months. Myelofibrosis, panleukopenia, anemia, and thrombocytopenia were ameliorated, the wart burden and frequency of infection declined, human papillomavirus-associated oropharyngeal squamous-cell carcinoma stabilized, and quality of life improved markedly. Adverse events were mainly infections attributable to the underlying immunodeficiency. One patient died from complications of elective reconstructive surgery. (Funded by the National Institutes of Health.).

A Critical Role of Formyl Peptide Receptors in Host Defense against Escherichia coli.

Formyl peptide receptors (FPRs, mouse Fprs) belong to the G protein-coupled receptor superfamily and mediate phagocyte migration in response to bacteria- and host-derived chemoattractants; however, knowledge about their in vivo roles in bacterial pathogenesis is limited. In this study, we investigated the role of Fpr1 and Fpr2 in host defense against Escherichia coli infection. In vitro, we found that supernatants from E. coli cultures induced chemotaxis of wild-type (WT) mouse bone marrow-derived neutrophils and that the activity was significantly reduced in cells genetically deficient in either Fpr1 or Fpr2 and was almost absent in cells lacking both receptors. Consistent with this, E. coli supernatants induced chemotaxis and MAPK phosphorylation in HEK293 cells expressing either recombinant Fpr1 or Fpr2 but not untransfected parental cells. WT bone marrow -derived neutrophils could actively phagocytose and kill E. coli, whereas both activities were diminished in cells lacking Fpr1 or Fpr2; again, an additive effect was observed in cells lacking both receptors. In vivo, Fpr1 and Fpr2 deficiency resulted in reduced recruitment of neutrophils in the liver and peritoneal cavity of mice infected with inactivated E. coli Moreover, Fpr1-/- and Fpr2-/- mice had significantly increased mortality compared with WT mice after i.p. challenge with a virulent E. coli clinical isolate. These results indicate a critical role of Fprs in host defense against E. coli infection.