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Proteases are signaling molecules that specifically control cellular functions by cleaving protease-activated receptors (PARs). The four known PARs are members of the large family of G protein-coupled receptors. These transmembrane receptors control most physiological and pathological processes and are the target of a large proportion of therapeutic drugs. Signaling proteases include enzymes from the circulation; from immune, inflammatory epithelial, and cancer cells; as well as from commensal and pathogenic bacteria. Advances in our understanding of the structure and function of PARs provide insights into how diverse proteases activate these receptors to regulate physiological and pathological processes in most tissues and organ systems. The realization that proteases and PARs are key mediators of disease, coupled with advances in understanding the atomic level structure of PARs and their mechanisms of signaling in subcellular microdomains, has spurred the development of antagonists, some of which have advanced to the clinic. Herein we review the discovery, structure, and function of this receptor system, highlight the contribution of PARs to homeostatic control, and discuss the potential of PAR antagonists for the treatment of major diseases.

Background: Women with breast cancer account for the largest cohort (23%) of over 18 million cancer survivors in the United States. Of the nearly 4 million breast cancer survivors, many, including individuals with metastatic breast cancer, will require lifelong treatment for chronic conditions. As part of a multi-site study including diverse tumor types, breast cancer survivors are being recruited to explore the feasibility and outcomes of a digital health coaching (DHC) program following the completion of primary therapy to support self-management of symptoms and general wellness. Trial design: A randomized-wait list control design will evaluate outcomes related to engagement in a DHC program following completion of primary therapy. Participants will be enrolled in a 6-month DHC program delivering evidence-based content via weekly calls, text, and email, in addition to usual support from their respective healthcare teams. The intervention group will receive coaching upon enrollment. The control group will receive coaching after a 6-month monitoring period. Twelve months of longitudinal clinical, patient-reported outcomes, activity tracking (via Fitbit), and microbiome data will be collected from both groups. Eligibility criteria: The breast cancer cohort will consist of individuals with both localized and metastatic disease within 1 year of completion of primary therapy, defined as treatment of curative intent, first-line or later, from which the individual is advancing to active surveillance or follow-up, with or without maintenance therapy. All study participants must be >18 years old, able to read and speak English, have access to mobile technology, and agree to wear and have data collected from an activity tracker. Specific aims: 1) Assess the feasibility and acceptability of a DHC program and its effect on participant health self-efficacy; 2) characterize associations between participant symptoms, physical/psychosocial well-being, and health self-management and gut microbiota changes; and 3) explore patient-generated health data outcomes among participants (patient reported and wearable biometrics outcomes). Statistical methods: Feasibility and acceptability will be assessed through descriptive statistics. Feasibility for this study is defined as a retention rate ≥70%, and acceptability is defined as ≤20% scoring “not at all helpful.” Secondary aims will be assessed using linear mixed models. Cross-cohort analysis of physical function, measured by the PROMIS Physical Function 10a, will be conducted. Assuming a power of 0.8 and significance level of .05, we will be able to detect a 2.51 difference in PROMIS score means between the control and intervention group (SD 10) with a sample of 500 total participants. Sub-group analysis will be conducted with the anticipated 250 participants in the breast cancer cohort with a focus on feasibility, acceptability, and descriptive and exploratory endpoints for this population as a whole and comparing early stage and metastatic participants. Target and present accruals: 500 individuals with diverse tumor types will be enrolled across 5 collaborating sites, of which 4 ill include individuals with breast cancer. An estimated 250 breast cancer participants (approximately 50% of the total study population), including 150 with de novo or progressive metastatic breast cancer, are planned to be recruited. To date, 1 Midwestern site has enrolled the first 7 breast cancer survivors. Two additional sites plan to enroll in July 2022, with the remaining 2 sites to begin enrollment by the end of 2022. Citation Format: Robin M. Lally, Rachael L. Schmidt, Gisele Tlusty, Elizabeth K. Arthur, Laura K. Flora, Jessica L. Krok-Schoen, Jessica T. Jones, Meagan Whisenant, Abbey Kaler, Debu Tripathy, Leorey Saligan, Marilyn Hammer, Austin Barr, Lindsey Jackson, Jennifer Loftis, Kelly J. Brassil. Breast Cancer Cohort of the Comprehensive Outcomes for After Cancer Health (COACH) Study: Study Protocol [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr OT2-06-01.

Dispersal is a critical parameter for successful pest control measures as it determines the rate of movement across target control areas and influences the risk of human exposure. We used a fine-scale spatial population genomic approach to investigate the dispersal ecology and population structure of Aedes notoscriptus, an important disease transmitting mosquito at the Mornington Peninsula, Australia. We sampled and reared Ae. notoscriptus eggs at two time points from 170 traps up to 5 km apart and generated genomic data from 240 individuals. We also produced a draft genome assembly from a laboratory colony established from mosquitoes sampled near the study area. We found low genetic structure (Fst) and high coancestry throughout the study region. Using genetic data to identify close kin dyads, we found that mosquitoes had moved distances of >1 km within a generation, which is further than previously recorded. A spatial autocorrelation analysis of genetic distances indicated genetic similarity at >1 km separation, a tenfold higher distance than for a comparable population of Ae. aegypti, from Cairns, Australia. These findings point to high mobility of Ae. notoscriptus, highlighting challenges of localised intervention strategies. Further sampling within the same area 6 and 12 months after initial sampling showed that egg-counts were relatively consistent across time, and that spatial variation in egg-counts covaried with spatial variation in Wright’s neighbourhood size (NS). As NS increases linearly with population density, egg-counts may be useful for estimating relative density in Ae. notoscriptus. The results highlight the importance of acquiring species-specific data when planning control measures.

The goal of this review is to describe the general features, mechanisms, technical recording factors, and clinical applications of brain evoked potentials (EPs) generated by deep brain stimulation (DBS) for Parkinson's disease (PD).Evoked potentials in response to DBS pulses occur on the timescale of milliseconds and are found both locally at the site of stimulation and remotely in the cortex. DBS evoked potentials arise from a complex integration of antidromic and orthodromic conduction pathway responses, and provide information valuable for understanding the mechanisms and circuits involved in symptom treatment. Furthermore, these signals may provide biomarkers for improving DBS outcomes and function. For example, evoked potentials may have utility as control signals for DBS programming or adaptive DBS. Despite their promise there are still critical gaps in our understanding of the mechanisms by which evoked potentials arise and how these signals may be measured and applied in the clinical setting. Technical challenges of recording a highly transient signal at sufficient resolution without the interference of stimulation artifact present a barrier to understanding better DBS-induced EPs.We describe the current scientific landscape of evoked potentials to facilitate and stimulate further investigation.

COVID-19 disproportionately impacted patients with cancer as a result of direct infection, and delays in diagnosis and therapy. Oncological clinical trials are resource-intensive endeavors that could be particularly susceptible to disruption by the pandemic, but few studies have evaluated the impact of the pandemic on clinical trial conduct.This prospective, multicenter study assesses the impact of the pandemic on therapeutic clinical trials at two large academic centers in the Northeastern United States between December 2019 and June 2021. The primary objective was to assess the enrollment on, accrual to, and activation of oncology therapeutic clinical trials during the pandemic using an institution-wide cohort of (i) new patient accruals to oncological trials, (ii) a manually curated cohort of patients with cancer, and (ii) a dataset of new trial activations.The institution-wide cohort included 4756 new patients enrolled to clinical trials from December 2019 to June 2021. A major decrease in the numbers of new patient accruals (-46%) was seen early in the pandemic, followed by a progressive recovery and return to higher-than-normal levels (+2.6%). A similar pattern (from -23.6% to +30.4%) was observed among 467 newly activated trials from June 2019 to June 2021. A more pronounced decline in new accruals was seen among academically sponsored trials (versus industry sponsored trials) (P0.05). In the manually curated cohort, which included 2361 patients with cancer, non-white patients tended to be more likely taken off trial in the early pandemic period (adjusted odds ratio: 2.60; 95% confidence interval 1.00-6.63), and substantial pandemic-related deviations were recorded.Substantial disruptions in clinical trial activities were observed early during the pandemic, with a gradual recovery during ensuing time periods, both from an enrollment and an activation standpoint. The observed decline was more prominent among academically sponsored trials, and racial disparities were seen among people taken off trial.

Since interactions and conflicts between polar bears (Ursus maritimus) and people are reportedly increasing across the Arctic, there is a pressing need to better understand how such conflicts can be prevented or their outcomes ameliorated. A great deal of knowledge about what strategies work for both preventing and mitigating human-polar bear conflicts lies with local experts, yet this knowledge has often remained relatively inaccessible to contemporary wildlife managers. This study had three main aims: to document and synthesize local knowledge of polar bear behaviour in Churchill, Manitoba, to characterize perceptions and interpretations of polar bears, and to examine the linkage between local experts’ knowledge, perceptions, and actions. We identified a suite of bear behaviours that local experts consistently observe and interpret as cues to the bears’ intent. These behaviours are not unique to this locale. Nevertheless, differences in perspectives on the predictability of polar bear behaviour and in interpretations of the nature of bears significantly influence study participants’ strategies for responding to bears. Our findings demonstrate that human-related factors are more complex than current models of human-bear interactions account for, so there is a need to develop richer models for understanding what motivates and influences human behaviours and responses towards bears.

Background Gender-affirming hormone therapy with either estradiol or testosterone is commonly prescribed for transgender individuals. Masculinizing or feminizing hormone therapy may impact clinical chemistry analytes, but there is currently a lack of published reference intervals for the transgender population. Methods Healthy transgender and nonbinary individuals who had been prescribed either estradiol (n = 93) or testosterone (n = 82) for at least 12 months were recruited from primary care and internal medicine clinics specializing in transgender medical care. Electrolytes, creatinine, urea nitrogen, enzymes (alkaline phosphatase, ALK; alanine aminotransferase, ALT; aspartate aminotransferase, AST; gamma-glutamyltransferase, GGT), hemoglobin A1c, lipids [total cholesterol, high-density lipoprotein (HDL), triglycerides], and high-sensitivity C-reactive protein (hsCRP) were measured on 2 clinical chemistry platforms. Reference intervals (central 95%) were calculated according to Clinical Laboratory Standards Institute guidelines. Results There was minimal impact of gender-affirming hormone therapy on electrolytes, urea nitrogen, hemoglobin A1c, and hsCRP. In general, the enzymes studied shifted toward affirmed gender. Creatinine values for both transgender cohorts overlaid the reference interval for cisgender men, with no shift toward affirmed gender for the estradiol cohort. The effects on lipids were complex, but with a clear shift to lower HDL values in the testosterone cohort relative to cisgender women. Conclusions Transgender individuals receiving either masculinizing or feminizing hormone therapy showed significant changes in some analytes that have sex-specific variation in the cisgender population. The clearest shifts toward affirmed gender were seen with enzymes for the estradiol and testosterone cohorts and with creatinine and HDL in the testosterone cohort.

This large, international dataset contains survey responses from N = 12,570 students from 100 universities in 35 countries, collected in 21 languages. We measured anxieties (statistics, mathematics, test, trait, social interaction, performance, creativity, intolerance of uncertainty, and fear of negative evaluation), self-efficacy, persistence, and the cognitive reflection test, and collected demographics, previous mathematics grades, self-reported and official statistics grades, and statistics module details. Data reuse potential is broad, including testing links between anxieties and statistics/mathematics education factors, and examining instruments’ psychometric properties across different languages and contexts. Data and metadata are stored on the Open Science Framework website [https://osf.io/mhg94/].

The hypothesis that sustained G protein-coupled receptor (GPCR) signaling from endosomes mediates pain is based on studies with endocytosis inhibitors and lipid-conjugated or nanoparticle-encapsulated antagonists targeted to endosomes. GPCR antagonists that reverse sustained endosomal signaling and nociception are needed. However, the criteria for rational design of such compounds are ill-defined. Moreover, the role of natural GPCR variants, which exhibit aberrant signaling and endosomal trafficking, in maintaining pain is unknown. Herein, substance P (SP) was found to evoke clathrin-mediated assembly of endosomal signaling complexes comprising neurokinin 1 receptor (NK 1 R), Gα q/i , and βarrestin-2. Whereas the FDA-approved NK 1 R antagonist aprepitant induced a transient disruption of endosomal signals, analogs of netupitant designed to penetrate membranes and persist in acidic endosomes through altered lipophilicity and pKa caused sustained inhibition of endosomal signals. When injected intrathecally to target spinal NK 1 R+ve neurons in knockin mice expressing human NK 1 R, aprepitant transiently inhibited nociceptive responses to intraplantar injection of capsaicin. Conversely, netupitant analogs had more potent, efficacious, and sustained antinociceptive effects. Mice expressing C-terminally truncated human NK 1 R, corresponding to a natural variant with aberrant signaling and trafficking, displayed attenuated SP-evoked excitation of spinal neurons and blunted nociceptive responses to SP. Thus, sustained antagonism of the NK 1 R in endosomes correlates with long-lasting antinociception, and domains within the C-terminus of the NK 1 R are necessary for the full pronociceptive actions of SP. The results support the hypothesis that endosomal signaling of GPCRs mediates nociception and provides insight into strategies for antagonizing GPCRs in intracellular locations for the treatment of diverse diseases.

Glycoprotein 90K, encoded by the interferon-stimulated gene LGALS3BP, displays broad antiviral activity. It reduces HIV-1 infectivity by interfering with Env maturation and virion incorporation, and increases survival of Influenza A virus-infected mice via antiviral innate immune signaling. Its antiviral potential in SARS-CoV-2 infection remains largely unknown. Here, we analyzed the expression of 90K/LGALS3BP in 44 hospitalized COVID-19 patients at multiple levels. We quantified 90K protein concentrations in serum and PBMCs as well as LGALS3BP mRNA levels. Complementary, we analyzed two single cell RNA-sequencing datasets for expression of LGALS3BP in respiratory specimens and PBMCs from COVID-19 patients. Finally, we analyzed the potential of 90K to interfere with SARS-CoV-2 infection of HEK293T/ACE2, Calu-3 and Caco-2 cells using authentic virus. 90K protein serum concentrations were significantly elevated in COVID-19 patients compared to uninfected sex- and age-matched controls. Furthermore, PBMC-associated concentrations of 90K protein were overall reduced by SARS-CoV-2 infection in vivo, suggesting enhanced secretion into the extracellular space. Mining of published PBMC scRNA-seq datasets uncovered monocyte-specific induction of LGALS3BP mRNA expression in COVID-19 patients. In functional assays, neither 90K overexpression in susceptible cell lines nor exogenous addition of purified 90K consistently inhibited SARS-CoV-2 infection. Our data suggests that 90K/LGALS3BP contributes to the global type I IFN response during SARS-CoV-2 infection in vivo without displaying detectable antiviral properties in vitro.

Deep brain stimulation (DBS) has shown great promise toward treating motor symptoms caused by Parkinson's disease (PD), by delivering electrical pulses to the Basal Ganglia (BG) region of the brain. However, DBS devices approved by the U.S. Food and Drug Administration (FDA) can only deliver continuous DBS (cDBS) stimuli at a fixed amplitude; this energy inefficient operation reduces battery lifetime of the device, cannot adapt treatment dynamically for activity, and may cause significant side-effects (e.g., gait impairment). In this work, we introduce an offline reinforcement learning (RL) framework, allowing the use of past clinical data to train an RL policy to adjust the stimulation amplitude in real time, with the goal of reducing energy use while maintaining the same level of treatment (i.e., control) efficacy as cDBS. Moreover, clinical protocols require the safety and performance of such RL controllers to be demonstrated ahead of deployments in patients. Thus, we also introduce an offline policy evaluation (OPE) method to estimate the performance of RL policies using historical data, before deploying them on patients. We evaluated our framework on four PD patients equipped with the RC+S DBS system, employing the RL controllers during monthly clinical visits, with the overall control efficacy evaluated by severity of symptoms (i.e., bradykinesia and tremor), changes in PD biomakers (i.e., local field potentials), and patient ratings. The results from clinical experiments show that our RL-based controller maintains the same level of control efficacy as cDBS, but with significantly reduced stimulation energy. Further, the OPE method is shown effective in accurately estimating and ranking the expected returns of RL controllers., Accepted to International Conference on Cyber Physical Systems (ICCPS) 2023

Context.— Pathologists have produced a substantial body of literature on graduate medical education (GME). However, this body of literature is diverse and has not yet been characterized. Objective.— To chart the concepts, research methods, and publication patterns of studies on GME in pathology. Data Sources.— This was a systematic scoping review covering all literature produced since 1980 in the PubMed and Embase databases. Conclusions.— Research on GME in pathology is evenly dispersed across educational topics. This body of literature would benefit from research based on theory, stronger study designs, and studies that can provide evidence to support decisions on educational policies.

Table S2. Confirmed best overall response per RECIST-1.1 by tumor type

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Figure S4. Changes in intratumoral immune markers after treatment

Purpose:Immune checkpoint inhibitors show high response rates and durable clinical benefit in microsatellite instability–high/mismatch repair–deficient (MSI-H/dMMR) tumors. However, 50%–60% do not respond to single-agent anti–programmed death-1/programmed death ligand 1 (PD-1/PD-L1) antibodies, and approximately 50% of responders relapse within 6–12 months. This phase Ib trial evaluated safety and antitumor activity of anti–PD-L1 antibody LY3300054 monotherapy or in combination with anti–TIM-3 antibody LY3321367 in patients with MSI-H/dMMR advanced solid tumors.Patients and Methods:Eligible patients ≥18 years without prior anti–PD-1/PD-L1 therapy received LY3300054 monotherapy (N = 40) or combination (N = 20); patients with PD-1/PD-L1 inhibitor–resistant/refractory tumors received the combination (N = 22). LY3300054 (700 mg) and anti–TIM-3 antibody (cycles 1–2: 1,200 mg, cycle 3 onward: 600 mg) were administered intravenously every 2 weeks. Primary endpoints were safety and tolerability.Results:Eighty-two patients were enrolled. Most had colorectal (n = 39, 47.6%) or endometrial (n = 14, 17.1%) tumors. More than 70% of patients in the PD-1/PD-L1 inhibitor–resistant/refractory combination cohort had received ≥3 treatment lines. Treatment-related adverse events (TRAE) occurred in 22 patients (55.0%) receiving monotherapy, 13 (65.0%) in the PD-1/PD-L1 inhibitor–naïve combination cohort, and 6 (27.3%) in the PD-1/PD-L1 inhibitor–resistant/refractory combination cohort. A total of 2 patients (5.0%) receiving monotherapy and 3 (7.1%) receiving the combination experienced grade ≥3 TRAEs. Objective responses occurred in 13 patients (32.5%) with monotherapy, 9 (45.0%) in the PD-1/PD-L1 inhibitor–naïve combination cohort, and 1 patient (4.5%) in the PD-1/PD-L1 inhibitor–resistant/refractory combination cohort.Conclusions:LY3300054 monotherapy and combined LY3300054/anti–TIM-3 had manageable safety profiles. Both regimens showed promising clinical activity against PD-1/PD-L1 inhibitor–naïve MSI-H/dMMR tumors. The combination had limited clinical benefit in patients with PD-1/PD-L1 inhibitor–resistant/refractory MSI-H/dMMR tumors.

Supplementary Materials and Methods and Supplementary Figures

Supplementary Figure S3. (A and B) The graphs compare beta-endorphin levels in the supernatant of oral SCC (HSC-3) cells re-expressing mu-opioid receptor and control oral SCC cells, with and without naloxone treatment. Cells transduced with Ad-OPRM1 at 200 MOI secreted an average of 400pg/ml beta-endorphin, which was significantly higher than non-transduced cells (*p < 0.05, One-way ANOVA, Holm-Sidak test). When treated with naloxone (10-6 to 10-12 mol/L) Ad-OPRM1 HSC-3 cells secreted significantly less beta-endorphin than the control vehicle-treated Ad-OPRM1 HSC-3 cells at all naloxone concentrations (p

Although macrophages (MΦ) are known to play a central role in neuropathic pain, their contribution to cancer pain has not been established. Here we report that depletion of sciatic nerve resident MΦs (rMΦ) in mice attenuates mechanical/cold hypersensitivity and spontaneous pain evoked by intraplantar injection of melanoma or lung carcinoma cells. MΦ-colony stimulating factor (M-CSF) was upregulated in the sciatic nerve trunk and mediated cancer-evoked pain via rMΦ expansion, transient receptor potential ankyrin 1 (TRPA1) activation, and oxidative stress. Targeted deletion of Trpa1 revealed a key role for Schwann cell TRPA1 in sciatic nerve rMΦ expansion and pain-like behaviors. Depletion of rMΦs in a medial portion of the sciatic nerve prevented pain-like behaviors. Collectively, we identified a feed-forward pathway involving M-CSF, rMΦ, oxidative stress, and Schwann cell TRPA1 that operates throughout the nerve trunk to signal cancer-evoked pain.Significance:Schwann cell TRPA1 sustains cancer pain through release of M-CSF and oxidative stress, which promote the expansion and the proalgesic actions of intraneural macrophages.

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Purpose: In this study, we evaluated the analgesic potential of demethylating drugs on oral cancer pain. Although demethylating drugs could affect expression of many genes, we focused on the mu-opioid receptor (OPRM1) gene pathway, because of its role in pain processing. We determined the antinociceptive effect of OPRM1 re-expression in a mouse oral cancer model.Experimental Design: Using a mouse oral cancer model, we determined whether demethylating drugs produced antinociception through re-expression of OPRM1. We then re-expressed OPRM1 with adenoviral transduction and determined if, and by what mechanism, OPRM1 re-expression produced antinociception. To determine the clinical significance of OPRM1 on cancer pain, we quantified OPRM1 methylation in painful cancer tissues and nonpainful contralateral normal tissues of patients with oral cancer, and nonpainful dysplastic tissues of patients with oral dysplasia.Results: We demonstrated that OPRM1 was methylated in cancer tissue, but not normal tissue, of patients with oral cancer, and not in dysplastic tissues from patients with oral dysplasia. Treatment with demethylating drugs resulted in mechanical and thermal antinociception in the mouse cancer model. This behavioral change correlated with OPRM1 re-expression in the cancer and associated neurons. Similarly, adenoviral-mediated OPRM1 re-expression on cancer cells resulted in naloxone-reversible antinociception. OPRM1 re-expression on oral cancer cells in vitro increased β-endorphin secretion from the cancer, and decreased activation of neurons that were treated with cancer supernatant.Conclusion: Our study establishes the regulatory role of methylation in cancer pain. OPRM1 re-expression in cancer cells produces antinociception through cancer-mediated endogenous opioid secretion. Demethylating drugs have an analgesic effect that involves OPRM1. Clin Cancer Res; 20(18); 4882–93. ©2014 AACR.

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Purpose: Problems in management of oral cancers or precancers include identification of patients at risk for metastasis, tumor recurrence, and second primary tumors or risk for progression of precancers (dysplasia) to cancer. Thus, the objective of this study was to clarify the role of genomic aberrations in oral cancer progression and metastasis.Experimental Design: The spectrum of copy number alterations in oral dysplasia and squamous cell carcinomas (SCC) was determined by array comparative genomic hybridization. Associations with clinical characteristics were studied and results confirmed in an independent cohort.Results: The presence of one or more of the chromosomal aberrations +3q24-qter, -8pter-p23.1, +8q12-q24.2, and +20 distinguishes a major subgroup (70%–80% of lesions, termed 3q8pq20 subtype) from the remainder (20%–30% of lesions, non-3q8pq20). The 3q8pq20 subtype is associated with chromosomal instability and differential methylation in the most chromosomally unstable tumors. The two subtypes differ significantly in clinical outcome with risk for cervical (neck) lymph node metastasis almost exclusively associated with the 3q8pq20 subtype in two independent oral SCC cohorts.Conclusions: Two subtypes of oral lesions indicative of at least two pathways for oral cancer development were distinguished that differ in chromosomal instability and risk for metastasis, suggesting that +3q,–8p, +8q, and +20 constitute a biomarker with clinical utility for identifying patients at risk for metastasis. Moreover, although increased numbers of genomic alterations can be harbingers of progression to cancer, dysplastic lesions lacking copy number changes cannot be considered benign as they are potential precursors to non-3q8pq20 locally invasive, yet not metastatic oral SCC. Clin Cancer Res; 17(22); 7024–34. ©2011 AACR.

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Supplementary Materials and Methods from Inhibition of RAS-Mediated Transformation and Tumorigenesis by Targeting the Downstream E3 Ubiquitin Ligase Seven in Absentia Homologue

Supplementary Figure 1 from Inhibition of RAS-Mediated Transformation and Tumorigenesis by Targeting the Downstream E3 Ubiquitin Ligase Seven in Absentia Homologue

Supplementary Figure 3 from Inhibition of RAS-Mediated Transformation and Tumorigenesis by Targeting the Downstream E3 Ubiquitin Ligase Seven in Absentia Homologue

Supplementary Table 1 from Inhibition of RAS-Mediated Transformation and Tumorigenesis by Targeting the Downstream E3 Ubiquitin Ligase Seven in Absentia Homologue

Supplementary Figure 4 from Inhibition of RAS-Mediated Transformation and Tumorigenesis by Targeting the Downstream E3 Ubiquitin Ligase Seven in Absentia Homologue

Supplementary Figure 5 from Inhibition of RAS-Mediated Transformation and Tumorigenesis by Targeting the Downstream E3 Ubiquitin Ligase Seven in Absentia Homologue

Supplementary Figure 2 from Inhibition of RAS-Mediated Transformation and Tumorigenesis by Targeting the Downstream E3 Ubiquitin Ligase Seven in Absentia Homologue

Constitutively active RAS small GTPases promote the genesis of human cancers. An important goal in cancer biology is to identify means of countervailing activated RAS signaling to reverse malignant transformation. Oncogenic K-RAS mutations are found in virtually all pancreatic adenocarcinomas, making the RAS pathway an ideal target for therapeutic intervention. How to best contravene hyperactivated RAS signaling has remained elusive in human pancreatic cancers. Guided by the Drosophila studies, we reasoned that a downstream mediator of RAS signals might be a suitable anti-RAS target. The E3 ubiquitin ligase seven in absentia (SINA) is an essential downstream component of the Drosophila RAS signal transduction pathway. Thus, we determined the roles of the conserved human homologues of SINA, SIAHs, in mammalian RAS signaling and RAS-mediated tumorigenesis. We report that similar to its Drosophila counterpart, human SIAH is also required for oncogenic RAS signaling in pancreatic cancer. Inhibiting SIAH-dependent proteolysis blocked RAS-mediated focus formation in fibroblasts and abolished the tumor growth of human pancreatic cancer cells in soft agar as well as in athymic nude mice. Given the high level of conservation of RAS and SIAH function, our study provides useful insights into altered proteolysis in the RAS pathway in tumor initiation, progression, and oncogenesis. By targeting SIAH, we have found a novel means to contravene oncogenic RAS signaling and block RAS-mediated transformation/tumorigenesis. Thus, SIAH may offer a novel therapeutic target to halt tumor growth and ameliorate RAS-mediated pancreatic cancer. [Cancer Res 2007;67(24):11798–810]