Unfavorable transcriptome profiles and social disadvantage in hematopoietic cell transplantation: a CIBMTR analysis.

Patient-reported outcomes (PROs) capture subjective social determinants of health (SDOHs), which can affect health outcomes through the stress response pathway. The conserved transcriptional response to adversity (CTRA) is a stress-mediated proinflammatory transcriptomic pattern that has been linked to adverse hematopoietic cell transplant (HCT) outcomes. This study examined the association of pretransplant CTRA with patient-reported SDOHs in allogeneic HCT recipients. In this cross-sectional study, pre-HCT SDOH-related PROs included the 36-Item Short Form Health Survey and the Functional Assessment of Cancer Therapy-Bone Marrow Transplant (FACT-BMT). CTRA was assessed by RNA sequencing of whole blood specimens, with mixed effects linear regression models relating CTRA expression to PRO scores while controlling for age, sex, race, disease, and performance status. Among 121 patients, the median age was 54 years, 42% were female, and 91% were White. CTRA was elevated in participants reporting lower scores on the FACT-BMT (P = .003), including the general (P = .003) and BMT-specific (P = .014) components. Effects were driven by the social well-being domain (P = .0001). This corresponded to an 8% to 15% difference in CTRA RNA expression across a 4 standard deviation range in patient-reported SDOHs. Ancillary bioinformatics analyses confirmed the association of well-being with reduced proinflammatory transcription pathway activity [cyclic AMP response element-binding protein, (CREB), NF-κB, and activating protein-1 (AP-1)]. In conclusion, HCT-treated patients who experience unfavorable social conditions show elevated CTRA expression in pretransplant blood samples. These data highlight the biologic sequelae of social well-being and community context and suggest a potential molecular mechanism for the impact of social gradients in HCT outcomes. Targeting this pathway could optimize outcomes in this high-risk population.

Respiratory Failure Due to Idiopathic Pneumonia Syndrome in a Pediatric Patient After Recipient-derived Allogeneic Chimeric Antigen Receptor T-Cell Therapy.

Idiopathic pneumonia syndrome (IPS) is a life-threatening complication of hematopoietic cell transplantation, but it is not clearly described following chimeric antigen receptor (CAR) T-cell therapy. We describe a child who developed IPS after receiving tisagenlecleucel for post-hematopoietic cell transplantation relapsed acute lymphoblastic leukemia and had a remarkable improvement after treatment with corticosteroids and etanercept. We discuss the implications of cytokine signaling in IPS and immunologic considerations of allogeneic CAR T cells. We anticipate that the incidence of IPS and other allogeneic phenomena will be observed more often as allogeneic CAR T cells are employed in more varied settings with more mismatched donors.

Evaluation of Children with Malignancies for Blood and Marrow Transplantation: A Report from the ASTCT Committee on Practice Guidelines.

Evaluation of a candidate for hematopoietic cell transplantation (HCT) is a complex process with substantial intercenter variability. Although literature providing guidance for evaluating the eligibility of adults is well established, similar guidance for children is lacking. To address gaps between adult recommendations and the specific needs of children, we convened a panel of pediatric HCT experts from a wide geographic range of American Society of Transplantation and Cellular Therapy (ASTCT) member institutions to offer recommendations for pediatric-focused pre-HCT evaluation. In this report from the ASTCT Committee on Practice Guidelines, we present a practical framework for evaluating children with malignancies who are candidates for HCT. We also highlight key differences from adults and emphasize areas of unmet need that require additional research to delineate best practices.

Comparison of toxicity following single versus tandem autologous transplant regimens for pediatric medulloblastoma.

BACKGROUND: Medulloblastoma outcomes have improved with craniospinal irradiation and chemotherapy, but such therapy has resulted in poor neurocognitive outcomes for young patients. Chemotherapy-only regimens with autologous transplant have been implemented with the intention of avoiding radiation. It is not yet known whether single or tandem transplantation is superior with respect to efficacy and/or safety. METHODS: We performed a retrospective review of children with medulloblastoma treated at Dana-Farber Cancer Institute from 1996 to 2016 who received either single or tandem autologous transplantation after completion of induction chemotherapy. We compared safety and outcome data between the two groups. RESULTS: Among 23 patients, 12 received tandem transplants. Median follow-up was 6.4 years (IQR = 0.8-10.5). There was no statistically significant difference in 5-year EFS or OS between the single (70.7 ± 14%, 80.2 ± 13%) and tandem transplant groups (57.1 ± 15%, 79.6 ± 13%). Seven tandem transplant patients received subsequent radiation while only four required radiation in the single transplant group (p = .41). In the single transplant regimen, patients experienced longer antibiotic duration (p = .03) and LOS (p = .01) and a trend toward increased number of transfusions (p = .06). Four cases of veno-occlusive disease were reported in the single transplant group (p = .04). CONCLUSIONS: Outcomes were similar between regimens, but the single transplant regimen had more hepatic complications. These data suggest that tandem transplant regimens may have reduced toxicity compared to the single transplant regimen with similar outcome measures.

MultiBench: Multiscale Benchmarks for Multimodal Representation Learning.

Learning multimodal representations involves integrating information from multiple heterogeneous sources of data. It is a challenging yet crucial area with numerous real-world applications in multimedia, affective computing, robotics, finance, human-computer interaction, and healthcare. Unfortunately, multimodal research has seen limited resources to study (1) generalization across domains and modalities, (2) complexity during training and inference, and (3) robustness to noisy and missing modalities. In order to accelerate progress towards understudied modalities and tasks while ensuring real-world robustness, we release MultiBench, a systematic and unified large-scale benchmark for multimodal learning spanning 15 datasets, 10 modalities, 20 prediction tasks, and 6 research areas. MultiBench provides an automated end-to-end machine learning pipeline that simplifies and standardizes data loading, experimental setup, and model evaluation. To enable holistic evaluation, MultiBench offers a comprehensive methodology to assess (1) generalization, (2) time and space complexity, and (3) modality robustness. MultiBench introduces impactful challenges for future research, including scalability to large-scale multimodal datasets and robustness to realistic imperfections. To accompany this benchmark, we also provide a standardized implementation of 20 core approaches in multimodal learning spanning innovations in fusion paradigms, optimization objectives, and training approaches. Simply applying methods proposed in different research areas can improve the state-of-the-art performance on 9/15 datasets. Therefore, MultiBench presents a milestone in unifying disjoint efforts in multimodal machine learning research and paves the way towards a better understanding of the capabilities and limitations of multimodal models, all the while ensuring ease of use, accessibility, and reproducibility. MultiBench, our standardized implementations, and leaderboards are publicly available, will be regularly updated, and welcomes inputs from the community.

Changes in glomerular filtration rate and clinical course after sequential doses of carboplatin in children with embryonal brain tumors undergoing autologous stem cell transplantation.

BACKGROUND: Treatment for malignant embryonal brain tumors in young children usually employs cycles of standardly dosed cisplatinum followed by high-dose carboplatinum-containing conditioning with single or tandem autologous stem cell rescue (HDC-ASCR). High-dose carboplatin is potentially nephrotoxic, and additive platinum exposure may acutely impact renal function. Aiming to determine if decrease in renal function during conditioning assessed prior to each carboplatin dose was associated with acute increases in creatinine, requirement for dialysis or transplant-related mortality (TRM). This was a retrospective study of consecutive patients with medulloblastoma (n = 15) / atypical teratoid/rhabdoid tumor (AT/RT, n = 5) receiving HDC-ASCR. Fifteen patients underwent 1 HDC-ASCR (carboplatin × 3 doses/ etoposide/ thiotepa) and 5 patients underwent at least 1 of 3 planned tandem HDC-ASCR (carboplatin × 2 doses/ thiotepa). Renal function was assessed by daily creatinine and nuclear medicine glomerular filtration rate (GFR)/ creatinine clearance before each carboplatin dose. RESULTS: In this cohort of 20 patients, 3 had doses of carboplatin omitted due to decreases in GFR: 1 did not develop nephrotoxicity, 1 experienced nephrotoxicity without need for dialysis, and 1 required dialysis temporarily but recovered renal function. Two patients did not have GFR changes but developed post-ASCR renal failure requiring dialysis and TRM. CONCLUSION: Daily assessment of renal function by GFR, prior each dose of carboplatin during HDC-ASCR, will help in protecting the kidney in heavily treated population of oncology/HSCT patients. Although the study had a small number of patients which is a major limitation of the study, but it points to a serious transplant-related morbidity and mortality. So, larger scale studies are needed to clarify the best approach to carboplatin dosing to insure the optimal balance between efficacy and toxicity.

Dose-escalated interleukin-2 therapy for refractory chronic graft-versus-host disease in adults and children.

Low-dose interleukin-2 (IL-2) therapy for chronic graft-versus-host disease (cGVHD) generates a rapid rise in plasma IL-2 levels and CD4+CD25+CD127-Foxp3+ regulatory T-cell (CD4Treg) proliferation, but both decrease over time despite continued daily administration. To test whether IL-2 dose escalation at the time of anticipated falls in plasma levels could circumvent tachyphylaxis and enhance CD4Treg expansion, we conducted a phase 1 trial in 10 adult and 11 pediatric patients with steroid-refractory cGVHD (www.clinicaltrials.gov: NCT02318082). Daily IL-2 was initiated in children and adults (0.33 × 106 and 0.67 × 106 IU/m2 per day, respectively). Dose escalations were scheduled at weeks 2 and 4 to a maximum dose of 1 × 106 IU/m2 per day in children and 2 × 106 IU/m2 per day in adults. Patients continued at their maximum tolerated dose (MTD) until week 8. Children tolerated IL-2 dose escalation with partial responses (PRs) in 9 of 11 patients (82%) at multiple cGVHD sites, including lung. Patient-reported outcome scores for skin and lung improved significantly in pediatric patients. In contrast, 5 of 10 adults required dose reduction, and only 2 of 7 evaluable patients (29%) had PRs at week 8. CD4Tregs and natural killer cells expanded in both cohorts without significant changes in conventional CD4+ T cells (Tcons) or CD8+ T cells. Children achieved a higher median CD4Treg/Tcon ratio at week 8 (0.4 vs 0.18, P = .02) despite lower IL-2 doses. We show for the first time that low-dose IL-2 is safe and effective in children with advanced cGVHD. In adults, escalation above the previously defined MTD did not improve CD4Treg expansion or clinical response.

Social-environmental drivers inform strategic management of coral reefs in the Anthropocene.

Without drastic efforts to reduce carbon emissions and mitigate globalized stressors, tropical coral reefs are in jeopardy. Strategic conservation and management requires identification of the environmental and socioeconomic factors driving the persistence of scleractinian coral assemblages-the foundation species of coral reef ecosystems. Here, we compiled coral abundance data from 2,584 Indo-Pacific reefs to evaluate the influence of 21 climate, social and environmental drivers on the ecology of reef coral assemblages. Higher abundances of framework-building corals were typically associated with: weaker thermal disturbances and longer intervals for potential recovery; slower human population growth; reduced access by human settlements and markets; and less nearby agriculture. We therefore propose a framework of three management strategies (protect, recover or transform) by considering: (1) if reefs were above or below a proposed threshold of >10% cover of the coral taxa important for structural complexity and carbonate production; and (2) reef exposure to severe thermal stress during the 2014-2017 global coral bleaching event. Our findings can guide urgent management efforts for coral reefs, by identifying key threats across multiple scales and strategic policy priorities that might sustain a network of functioning reefs in the Indo-Pacific to avoid ecosystem collapse.

Pediatric CNS-isolated hemophagocytic lymphohistiocytosis.

Objective: To highlight a novel, treatable syndrome, we report 4 patients with CNS-isolated inflammation associated with familial hemophagocytic lymphohistiocytosis (FHL) gene mutations (CNS-FHL). Methods: Retrospective chart review. Results: Patients with CNS-FHL are characterized by chronic inflammation restricted to the CNS that is not attributable to any previously described neuroinflammatory etiology and have germline mutations in known FHL-associated genes with no signs of systemic inflammation. Hematopoietic stem cell transplantation (HCT) can be well tolerated and effective in achieving or maintaining disease remission in patients with CNS-FHL. Conclusions: Early and accurate diagnosis followed by treatment with HCT can reduce morbidity and mortality in CNS-FHL, a novel, treatable syndrome. Classification of evidence: This study provides Class IV evidence that HCT is well tolerated and effective in treating CNS-FHL.

Diagnostic upgrade of atypical ductal hyperplasia of the breast based on evaluation of histopathological features and calcification on core needle biopsy.

AIMS: Atypical ductal hyperplasia (ADH) of breast is increasingly diagnosed in core needle biopsy (CNB). As higher-grade lesions were found in the excision in a substantial proportion of ADH on CNB, factors predicting risk of subsequent upgrade are clinically significant. This study aims to investigate relevant histopathological factors in CNB that could predict diagnostic upgrade at excision. METHODS AND RESULTS: One hundred and forty-three cases of CNB with paired subsequent excision were evaluated for multiple clinicopathological parameters related to CNB sampling, ADH morphology, calcification and other co-existing histological features, and which of these parameters were associated with diagnostic upgrade at subsequent excisions were determined. Forty-eight cases (34.3%) were upgraded to malignancy, including 15 invasive cancers and 33 ductal carcinomas in situ (DCIS). An increased tissue area occupied by ADH (P = 0.026), a higher number of ADH foci (P = 0.004), the presence of solid pattern (P = 0.037) and older age (P = 0.012) were positively associated with upgrade, while negative associations were found with the presence of micropapillary pattern (P = 0.025), co-existing columnar cell lesions (CCL) (P = 0.001) and the presence of calcifications (P = 0.009). Multivariate logistic regression analysis showed that the number of ADH foci (HR = 2.810, P = 0.013) was an independent positive predictor, while co-existing CCL (HR = 0.391, P = 0.013) was an independent negative predictor for upgrade. CONCLUSIONS: Patients with ADH in CNB showing the presence of co-existing CCL and a lower number of ADH foci have a lower risk of disease upgrade at excision, and are potential candidates for observation-only management.

The Clinical Value of PELP1 for Breast Cancer: A Comparison with Multiple Cancers and Analysis in Breast Cancer Subtypes.

PURPOSE: Proline, glutamic acid, and leucine-rich protein 1 (PELP1), a novel nuclear receptor (NR) co-regulator, is highly expressed in breast cancer. We investigated its expression in breast cancer subtypes, in comparison with other breast markers as well as cancers from different sites. Its prognostic relevance with different subtypes and other NR expression was also examined in breast cancers. METHODS: Immunohistochemical analysis was performed on totally 1,944 cancers from six different organs. RESULTS: PELP1 expression rate was the highest in breast cancers (70.5%) among different cancers. Compared to GATA3, mammaglobin and gross cystic disease fluid protein 15, PELP1 was less sensitive than GATA3 for luminal cancers, but was the most sensitive for non-luminal cancers. PELP1 has low expression rate (<20%) in colorectal cancers, gastric cancers and renal cell carcinomas, but higher in lung cancers (49.1%) and ovarian cancers (42.3%). In breast cancer, PELP1 expression was an independent adverse prognostic factor for non-luminal cancers (disease-free survival [DFS]: hazard ratio [HR], 1.403; p=0.012 and breast cancer specific survival [BCSS]: HR, 1.443; p=0.015). Interestingly, its expression affected the prognostication of androgen receptor (AR). ARposPELP1lo luminal cancer showed the best DFS (log-rank=8.563, p=0.036) while ARnegPELP1hi non-luminal cancers showed the worst DFS (log-rank=9.536, p=0.023). CONCLUSION: PELP1 is a sensitive marker for breast cancer, particularly non-luminal cases. However, its considerable expression in lung and ovarian cancers may limit its utility in differential diagnosis in some scenarios. PELP1 expression was associated with poor outcome in non-luminal cancers and modified the prognostic effects of AR, suggesting the potential significance of NR co-regulator in prognostication.

Proteolytic cleavage of amyloid precursor protein by ADAM10 mediates proliferation and migration in breast cancer.

BACKGROUND: Amyloid precursor protein (APP), best known for its association with Alzheimer disease, has recently been implicated in breast cancer progression. However, the precise mechanism involved remains unclear. Here, we investigated the role of APP proteolytic cleavage in breast cancer functions. METHODS: The presence of APP proteolytic cleavage products was examined in breast cancer cell lines. The functional roles of APP in breast cancer were studied in vitro and tumor xenograft model using siRNA. The effects of full length APP and the α-secretase cleaved ectodomain fragment, soluble APPα (sAPPα) were further investigated for their overexpression in breast cancers. The α-secretase involved was identified. The α-secretase expression together with APP was examined in clinical breast cancers. RESULTS: We showed that APP underwent proteolytic cleavage in breast cancer cells to generate sAPPα. The sAPPα and full length protein mediated breast cancer migration and proliferation, but in different functional extent. This proteolytic cleavage was mediated by ADAM10. Downregulation of APP and ADAM10 brought about similar functional effects. Overexpression of sAPPα reversed the effects of ADAM10 downregulation. Interestingly, in patients with non-luminal breast cancers, APP and ADAM10 expression correlated with each other and their co-expression was associated with the worst outcome. CONCLUSIONS: These results demonstrated the contributory role of APP cleavage on its oncogenic roles in breast cancer. ADAM10 was the key α-secretase. APP and ADAM10 co-expression was associated with worse survival in non-luminal breast cancers. Targeting of APP or its processing by ADAM10 might be a promising treatment option in these cancers.

Amyloid Precursor Protein Is Associated with Aggressive Behavior in Nonluminal Breast Cancers.

BACKGROUND: ß-amyloid precursor protein (APP), a potential target for Alzheimer's disease treatment, has recently been shown to take part in carcinogenesis. Increased APP promotes migration, survival, and proliferation in breast cancer cell lines. We examined the clinical value of APP in breast cancers. A comprehensive examination of clinicopathological features related to APP expression in a large cohort of breast cancers and the corresponding metastatic lymph nodes was performed. APP expression and its prognostic impact in different breast cancer subtypes were examined. RESULTS: APP was highly expressed in nonluminal breast cancers and correlated with features associated with nonluminal breast cancers (including higher grade, the presence of necrosis, and higher proliferative index, growth factor receptor, and basal marker expression). Multivariate Cox hazard analysis demonstrated that APP was an independent adverse prognostic factor of disease-free survival (DFS; hazard ratio [HR], 2.090; p = .013; 95% confidence interval [CI], 1.165-3.748) and breast cancer-specific survival (BCSS; HR, 2.631; p = .002; 95% CI, 1.408-4.915) in the nonluminal group. The independent prognostic impact was also seen in triple negative breast cancers. Interestingly, a higher expression of APP was found in nodal metastasis compared with primary tumor. Such APP upregulation was correlated with further distal metastasis and poorer outcome (DFS: log-rank, 12.848; p < .001; BCSS: log-rank, 13.947; p < .001). CONCLUSION: Our findings provided evidence of oncogenic roles of APP in clinical breast cancers. Patients with positive APP expression, particularly those with APP upregulation in lymph node metastases, may require vigilant monitoring of their disease and more aggressive therapy. IMPLICATIONS FOR PRACTICE: ß-amyloid precursor protein (APP), a potential target for Alzheimer's disease, has recently been implicated in oncogenesis. Here, evidence of its roles in clinical breast cancers is provided. Positive APP expression was found to be an independent prognostic factor in nonluminal cancers, particularly triple negative breast cancers (TNBCs). Interestingly, a higher APP in nodal metastases was associated with distal metastases. TNBCs are heterogeneous and currently have no available target therapy. APP could have therapeutic potential and be used to define the more aggressive cases in TNBCs. Current prognostic analysis is based on primary tumor. The present data suggest that investigation of nodal metastases could provide additional prognostic value.

Association of clinicopathological features and prognosis of TERT alterations in phyllodes tumor of breast.

Phyllodes tumor (PT) of the breast is a rare but clinically important fibroepithelial tumor with potential risks of recurrence and metastasis. Recent studies identified recurrent TERT promoter mutations in PTs. However, the clinical significance of this alteration has not been fully examined. Two hundred and seven PTs from two intuitions were included. All cases were subjected to immunohistochemical analysis for TERT expression. Analysis of TERT promoter mutations was further performed by Sanger sequencing targeting the hotspot mutation region on cases from one of the involved institutions. The expression of TERT was correlated with clinicopathologic features, mutation status and recurrence. There was an association of TERT expression and its promoter mutation. Both stromal TERT expression and its promoter mutation correlated with PT grading and older patient age. Recurrence free survival (RFS) of PT patients with high stromal TERT expression was shorter if the excision margin was positive. Our findings suggested a possible pathogenic role of TERT alteration in PT malignancy. Currently there is no consensus for re-excision for PT patients with positive surgical margin, particularly for low grade cases. Stromal TERT expression could be potentially useful to guide management patients with benign PTs.

Outcomes Following Bone Marrow Transplantation in Children With Accelerated Phase or Blast Crisis Chronic Myelogenous Leukemia in the Era of Tyrosine Kinase Inhibitors.

The management of chronic myelogenous leukemia (CML) in children changed dramatically with the introduction of tyrosine kinase inhibitors (TKIs). Unfortunately, outcomes for patients presenting in an advanced stage-accelerated phase or blast crisis CML-continues to be poor, requiring chemotherapy and allogeneic hematopoietic stem cell transplant (HSCT) to attempt cure. Integration of TKIs in the therapy of advanced CML is still an area of active investigation. There are little published data on TKI use in children with advanced stage CML. We performed a retrospective review of all children treated at our institution between January 1, 2010 and June 30, 2013, and identified 5 children, age 12 to 18 years, with advanced stage CML. All patients were treated with a TKI before HSCT and TKIs were restarted post-HSCT in 4/5 with a goal of continuing until 2 years posttransplant. At time of HSCT all were in a morphologic and cytogenetic remission; 1 patient had also achieved molecular remission. All patients are alive and in molecular remission at an average of 38 months (range, 14 to 51 mo) following transplant. Our experience indicates that TKIs are safe and well tolerated in children both pretransplant and posttransplant and may improve outcomes in this aggressive disease.

Second Allogeneic Hematopoietic Cell Transplantation for Patients with Fanconi Anemia and Bone Marrow Failure.

A second allogeneic hematopoietic cell transplantation (HCT) is the sole salvage option for individuals who develop graft failure after their first HCT. Data on outcomes after second HCT in patients with Fanconi anemia (FA) are scarce. Here we report outcomes after second allogeneic HCT for FA (n = 81). The indication for second HCT was graft failure after the first HCT. Transplantations were performed between 1990 and 2012. The timing of the second HCT predicted subsequent graft failure and survival. Graft failure was high when the second HCT was performed less than 3 months from the first. The 3-month probability of graft failure was 69% when the interval between the first HCT and second HCT was less than 3 months, compared with 23% when the interval was longer (P < .001). Consequently, the 1-year survival rate was substantially lower when the interval between the first and second HCTs was less than 3 months compared with longer (23% vs 58%; P = .001). The corresponding 5-year probability of survival was 16% and 45%, respectively (P = .006). Taken together, these data suggest that fewer than one-half of patients with FA undergoing a second HCT for graft failure are long-term survivors. There is an urgent need to develop strategies to reduce the rate of graft failure after first HCT.

Passenger deletions generate therapeutic vulnerabilities in cancer.

Inactivation of tumour-suppressor genes by homozygous deletion is a prototypic event in the cancer genome, yet such deletions often encompass neighbouring genes. We propose that homozygous deletions in such passenger genes can expose cancer-specific therapeutic vulnerabilities when the collaterally deleted gene is a member of a functionally redundant family of genes carrying out an essential function. The glycolytic gene enolase 1 (ENO1) in the 1p36 locus is deleted in glioblastoma (GBM), which is tolerated by the expression of ENO2. Here we show that short-hairpin-RNA-mediated silencing of ENO2 selectively inhibits growth, survival and the tumorigenic potential of ENO1-deleted GBM cells, and that the enolase inhibitor phosphonoacetohydroxamate is selectively toxic to ENO1-deleted GBM cells relative to ENO1-intact GBM cells or normal astrocytes. The principle of collateral vulnerability should be applicable to other passenger-deleted genes encoding functionally redundant essential activities and provide an effective treatment strategy for cancers containing such genomic events.

Mig-6 controls EGFR trafficking and suppresses gliomagenesis.

Glioblastoma multiforme (GBM) is the most common and lethal primary brain cancer that is driven by aberrant signaling of growth factor receptors, particularly the epidermal growth factor receptor (EGFR). EGFR signaling is tightly regulated by receptor endocytosis and lysosome-mediated degradation, although the molecular mechanisms governing such regulation, particularly in the context of cancer, remain poorly delineated. Here, high-resolution genomic profiles of GBM identified a highly recurrent focal 1p36 deletion encompassing the putative tumor suppressor gene, Mig-6. We show that Mig-6 quells the malignant potential of GBM cells and dampens EGFR signaling by driving EGFR into late endosomes and lysosome-mediated degradation upon ligand stimulation. Mechanistically, this effect is mediated by the binding of Mig-6 to a SNARE protein STX8, a protein known to be required for late endosome trafficking. Thus, Mig-6 functions to ensure recruitment of internalized receptor to late endosomes and subsequently the lysosomal degradation compartment through its ability to specifically link EGFR and STX8 during ligand-stimulated EGFR trafficking. In GBM, the highly frequent loss of Mig-6 would therefore serve to sustain aberrant EGFR-mediated oncogenic signaling. Together, these data uncover a unique tumor suppression mechanism involving the regulation of receptor trafficking.