Connecting the αα-hubs: same fold, disordered ligands, new functions.

BACKGROUND: Signal fidelity depends on protein-protein interaction-'hubs' integrating cues from large interactomes. Recently, and based on a common secondary structure motif, the αα-hubs were defined, which are small α-helical domains of large, modular proteins binding intrinsically disordered transcriptional regulators. METHODS: Comparative structural biology. RESULTS: We assign the harmonin-homology-domain (HHD, also named the harmonin N-terminal domain, NTD) present in large proteins such as harmonin, whirlin, cerebral cavernous malformation 2, and regulator of telomere elongation 1 to the αα-hubs. The new member of the αα-hubs expands functionality to include scaffolding of supra-modular complexes mediating sensory perception, neurovascular integrity and telomere regulation, and reveal novel features of the αα-hubs. As a common trait, the αα-hubs bind intrinsically disordered ligands of similar properties integrating similar cellular cues, but without cross-talk. CONCLUSION: The inclusion of the HHD in the αα-hubs has uncovered new features, exemplifying the utility of identifying groups of hub domains, whereby discoveries in one member may cross-fertilize discoveries in others. These features make the αα-hubs unique models for decomposing signal specificity and fidelity. Using these as models, together with other suitable hub domain, we may advance the functional understanding of hub proteins and their role in cellular communication and signaling, as well as the role of intrinsically disordered proteins in signaling networks. Video Abstract.

Epidemiology of male breast cancer.

BACKGROUND: Due to its rarity, few studies have characterized the epidemiology of male breast cancer. The purpose of this study was to determine survival and risk factors for male breast cancer in a large U.S. METHODS: In this study, 19,795 male patients with breast cancer were identified from the National Cancer Database (2004-2014). Patient demographics, tumor characteristics and treatments were analyzed by using descriptive statistics. We used multivariate Cox regression and Kaplan Meier analysis. RESULTS: Over 10 years, the incidence of male breast cancer increased from 7.2% to 10.3%, while mortality decreased from 11% to 3.8%. Socioeconomic factors predicting mortality included income medium, and high vs low (HR = 0.78; 0.68), private vs no insurance (HR = 0.73) and the academic research facility vs community cancer center (HR = 0.79). Significant predictors of all-cause mortality included age (HR = 1.04), tumor size (HR = 1.01), hormone receptor expression (HR = 0.8) and cancer stage I vs II, III, and IV at the time of diagnosis (HR = 1.5, 2.7, 4.4, 9.9 respectively). Other predictors of mortality include surgery (HR = 0.4), chemotherapy (HR = 0.8), radiation (HR = 0.8), and hormonal therapy (HR-0.8). CONCLUSIONS: Socioeconomic factors, cancer stage, tumor characteristics (size and grade), and high Charlson-Dayo score contributed to higher mortality among male patients diagnosed with breast cancer. Surgery was most effective, followed by radiation, chemotherapy, and hormonal therapy. Patients with positive ER or PR expression demonstrated better survival. Adjusting for socioeconomic factors, biomarker identification and timely, appropriately chosen treatment are likely to reduce the risk for mortality.

High affinity between CREBBP/p300 and NCOA evolved in vertebrates.

The interaction between the transcriptional coactivators CREBBP/p300 and NCOA is governed by two intrinsically disordered domains called NCBD and CID, respectively. The CID domain emerged within the NCOA protein in deuterostome animals (including vertebrates) after their split from the protostomes (molluscs, worms, and arthropods). However, it has not been clear at which point a high affinity interaction evolved within the deuterostome clade and whether all present-day deuterostome animals have a high affinity NCBD:CID interaction. We have here expressed and measured affinity for NCBD and CID domains from animal species representing different evolutionary branches of the deuterostome tree. While all vertebrate species have high-affinity NCBD:CID interactions we found that the interaction in the echinoderm purple sea urchin is of similar affinity as that of the proposed ancestral domains. Our findings demonstrate that the high-affinity NCBD:CID interaction likely evolved in the vertebrate branch and question whether the interaction between CREBBP/p300 and NCOA is essential in nonvertebrate deuterostomes. The data provide an example of evolution of transcriptional regulation through protein-domain based inventions.

Hospital Volume Threshold for the Treatment of Retroperitoneal Sarcoma.

BACKGROUND: Retroperitoneal sarcomas (RPS) are rare, histologically heterogeneous, and anatomically complex tumors. National Comprehensive Cancer Network guidelines recommend evaluation and management by multidisciplinary teams with experience in sarcoma. Our aim was to determine an appropriate hospital volume threshold for the treatment of RPS. PATIENTS AND METHODS: Patients undergoing resection of RPS were identified from the National Cancer Data Base (1998-2012). Multivariable modeling with restricted cubic splines was employed to examine the association between hospital volume and survival and identify possible hospital volume threshold. RESULTS: The study included 5,340 patients who underwent surgery at 909 different hospitals. Median annual volume was two cases per year. After adjustment, hospital volume was associated with improved survival (p=0.01), without cutoff. The cohort was then grouped into: Low-volume (≤5 cases/year), intermediate-volume (6-10 cases/year), and high-volume (>10 cases/year). The majority of patients were treated in low-volume hospitals (86%), compared to 9% in intermediate- and 5% in high-volume centers; 44% of patients were treated in hospitals that performed one case per year. Compared to low-volume, high-volume hospitals more often had patients with high-grade and larger tumors. Adjusted 90-day mortality was significantly lower in high- vs. low-volume hospitals (odds ratio(OR)=0.25, p=0.02). With adjustment, treatment in high- vs. low-volume hospitals was associated with lower odds of margin positivity (OR=0.58, p=0.001), and improved overall survival (hazard ratio(HR)=0.61, p=0.002). CONCLUSION: Treatment of RPS in high-volume centers is associated with significant reduction in short-term mortality and improved long-term survival. Hospital volume may be a surrogate for the infrastructure and support necessary for the optimal management of these complex malignancies.

Structure of Radical-Induced Cell Death1 Hub Domain Reveals a Common αα-Scaffold for Disorder in Transcriptional Networks.

Communication within cells relies on a few protein nodes called hubs, which organize vast interactomes with many partners. Frequently, hub proteins are intrinsically disordered conferring multi-specificity and dynamic communication. Conversely, folded hub proteins may organize networks using disordered partners. In this work, the structure of the RST domain, a unique folded hub, is solved by nuclear magnetic resonance spectroscopy and small-angle X-ray scattering, and its complex with a region of the transcription factor DREB2A is provided through data-driven HADDOCK modeling and mutagenesis analysis. The RST fold is unique, but similar structures are identified in the PAH (paired amphipathic helix), TAFH (TATA-box-associated factor homology), and NCBD (nuclear coactivator binding domain) domains. We designate them as a group the αα hubs, as they share an αα-hairpin super-secondary motif, which serves as an organizing platform for malleable helices of varying topology. This allows for partner adaptation, exclusion, and selection. Our findings provide valuable insights into structural features enabling signaling fidelity.

Outcomes in Adult Sinonasal Rhabdomyosarcoma.

Objective To describe patient demographics, histology, treatment modalities, and survival associated with adult sinonasal rhabdomyosarcoma. Study Design Retrospective review of a national database. Setting Tertiary medical center. Subjects and Methods Patient demographics, tumor histology, treatment modalities, and survival trends were examined for patients aged ≥18 years who were diagnosed with sinonasal rhabdomyosarcoma between 2004 and 2013 with the National Cancer Database. Kaplan-Meier analysis and the log-rank tests were performed to determine the unadjusted association between overall survival and various patient and disease characteristics. Results A total of 186 patients were identified; 5-year overall survival was 28.4%. Over half of patients were between 18 and 35 years old at diagnosis (53.8%), which was associated with improved 5-year overall survival over patients >35 years old (31.9% vs 24.4%, P = .014). Alveolar sinonasal rhabdomyosarcoma was most common (66.7%). There was no statistical difference in 5-year overall survival between alveolar and embryonal subtypes (30.5% vs 41.6%, P > .05). Metastatic disease was present in 27.7% of patients and was associated with worse 5-year overall survival (14.7% vs 33.9%, P < .0001). The majority of patients were treated with chemotherapy with adjuvant radiation (49.5%). A quarter of patients were treated with surgery plus chemoradiation (25.8%). Conclusion We present the largest analysis of adult sinonasal rhabdomyosarcoma using a standardized national based database. Adult sinonasal rhabdomyosarcoma has a very poor prognosis independent of histologic subtype. The small number of surgical cases limits the ability of the analysis to accurately compare treatment with chemoradiation with and without surgery.