The Carolina hysterectomy cohort (CHC): a novel case series of reproductive-aged hysterectomy patients across 10 hospitals in the US south.

BACKGROUND: Hysterectomy is a common surgery among reproductive-aged U.S. patients, with rates highest among Black patients in the South. There is limited insight on causes of these racial differences. In the U.S., electronic medical records (EMR) data can offer richer detail on factors driving surgical decision-making among reproductive-aged populations than insurance claims-based data. Our objective in this cohort profile paper is to describe the Carolina Hysterectomy Cohort (CHC), a large EMR-based case-series of premenopausal hysterectomy patients in the U.S. South, supplemented with census and surgeon licensing data. To demonstrate one strength of the data, we evaluate whether patient and surgeon characteristics differ by insurance payor type. METHODS: We used structured and abstracted EMR data to identify and characterize patients aged 18-44 years who received hysterectomies for non-cancerous conditions between 10/02/2014-12/31/2017 in a large health care system comprised of 10 hospitals in North Carolina. We used Chi-squared and Kruskal Wallis tests to compare whether patients' socio-demographic and relevant clinical characteristics, and surgeon characteristics differed by patient insurance payor (public, private, uninsured). RESULTS: Of 1857 patients (including 55% non-Hispanic White, 30% non-Hispanic Black, 9% Hispanic), 75% were privately-insured, 17% were publicly-insured, and 7% were uninsured. Menorrhagia was more prevalent among the publicly-insured (74% vs 68% overall). Fibroids were more prevalent among the privately-insured (62%) and the uninsured (68%). Most privately insured patients were treated at non-academic hospitals (65%) whereas most publicly insured and uninsured patients were treated at academic centers (66 and 86%, respectively). Publicly insured and uninsured patients had higher median bleeding (public: 7.0, uninsured: 9.0, private: 5.0) and pain (public: 6.0, uninsured: 6.0, private: 3.0) symptom scores than the privately insured. There were no statistical differences in surgeon characteristics by payor groups. CONCLUSION: This novel study design, a large EMR-based case series of hysterectomies linked to physician licensing data and manually abstracted data from unstructured clinical notes, enabled identification and characterization of a diverse reproductive-aged patient population more comprehensively than claims data would allow. In subsequent phases of this research, the CHC will leverage these rich clinical data to investigate multilevel drivers of hysterectomy in an ethnoracially, economically, and clinically diverse series of hysterectomy patients.

Encapsulated Calcified Hematoma Mimicking a Cardiac Tumor, Diagnosed 25 Years Post-Traumatic Injury.

A 45-year-old man presented with nonspecific symptoms caused by a mass compressing the right ventricle. Cardiac computed tomography accurately predicted the operative and pathologic appearance of the mass, and the final diagnosis of an encapsulated cardiac hematoma was confirmed by pathologic examination. This condition is infrequent and mimics a cardiac tumor. (Level of Difficulty: Advanced.).

Single-cell multi-scale footprinting reveals the modular organization of DNA regulatory elements.

Cis-regulatory elements control gene expression and are dynamic in their structure, reflecting changes to the composition of diverse effector proteins over time1-3. Here we sought to connect the structural changes at cis-regulatory elements to alterations in cellular fate and function. To do this we developed PRINT, a computational method that uses deep learning to correct sequence bias in chromatin accessibility data and identifies multi-scale footprints of DNA-protein interactions. We find that multi-scale footprints enable more accurate inference of TF and nucleosome binding. Using PRINT with single-cell multi-omics, we discover wide-spread changes to the structure and function of candidate cis-regulatory elements (cCREs) across hematopoiesis, wherein nucleosomes slide, expose DNA for TF binding, and promote gene expression. Activity segmentation using the co-variance across cell states identifies "sub-cCREs" as modular cCRE subunits of regulatory DNA. We apply this single-cell and PRINT approach to characterize the age-associated alterations to cCREs within hematopoietic stem cells (HSCs). Remarkably, we find a spectrum of aging alterations among HSCs corresponding to a global gain of sub-cCRE activity while preserving cCRE accessibility. Collectively, we reveal the functional importance of cCRE structure across cell states, highlighting changes to gene regulation at single-cell and single-base-pair resolution.

Subcoronal inflatable penile prosthesis implantation: indications and outcomes.

BACKGROUND: While implantation of an inflatable penile prosthesis (IPP) is commonly performed via infrapubic or penoscrotal approaches, the subcoronal (SC) approach for IPP implantation may safely and reliably allow for additional reconstructive procedures through a single incision. AIM: The aim of this study is to report outcomes, including complications, of the SC approach and to determine common characteristics of patients undergoing the SC approach. METHODS: A retrospective chart review from May 11, 2012, to January 31, 2022, was performed at a single, tertiary care institution to identify patients with IPP implantation via the SC approach. OUTCOMES: Postoperative information was reviewed and extracted from all clinic notes available following the date of IPP implantation in the electronic medical record, detailing any complications including wound complications, need for revision or removal, device malfunction, and infections. RESULTS: Sixty-six patients had IPP implantation via the SC approach. Median follow-up duration was 29.4 (interquartile range 14.9-50.1) months. One (1.8%) patient had a simple wound complication. Two (3.6%) experienced postoperative infection of the prosthesis, which resulted in explantation of the device. One of these infected prostheses later experienced partial glans necrosis. Revision for mechanical failure or unsatisfactory cosmetic result was performed in 3 (7.3%) IPPs placed via a SC incision. CLINICAL IMPLICATIONS: The SC approach for implantation of IPP is safe and feasible with low complication and revision rates. It offers urologists an alternative to the classic infrapubic and penoscrotal approaches, both of which would require a second incision for additional reconstructive procedures required to adequately address deformities associated with severe Peyronie's disease. Therefore, urologists who treat these specialized populations of men may benefit from having the SC approach in their array of techniques for IPP implantation. STRENGTHS AND LIMITATIONS: The limitations of this study include its retrospective nature, risk of selection bias, lack of comparison groups, and sample size. This study reports on early experience with the SC approach performed by a single high-volume reconstructive surgeon, who treats a specialized population of patients requiring complex repair during implantation of an IPP, particularly those with Peyronie's disease. CONCLUSION: The SC incision for IPP implantation has low rates of complications and remains our approach of choice for IPP implantation in patients with severe Peyronie's disease, including curvatures >60°, severe indentation with hinge, and grade 3 calcification, which are unlikely to respond adequately to manual modeling alone.

Molecular classification and biomarkers of clinical outcome in breast ductal carcinoma in situ: Analysis of TBCRC 038 and RAHBT cohorts.

Ductal carcinoma in situ (DCIS) is the most common precursor of invasive breast cancer (IBC), with variable propensity for progression. We perform multiscale, integrated molecular profiling of DCIS with clinical outcomes by analyzing 774 DCIS samples from 542 patients with 7.3 years median follow-up from the Translational Breast Cancer Research Consortium 038 study and the Resource of Archival Breast Tissue cohorts. We identify 812 genes associated with ipsilateral recurrence within 5 years from treatment and develop a classifier that predicts DCIS or IBC recurrence in both cohorts. Pathways associated with recurrence include proliferation, immune response, and metabolism. Distinct stromal expression patterns and immune cell compositions are identified. Our multiscale approach employed in situ methods to generate a spatially resolved atlas of breast precancers, where complementary modalities can be directly compared and correlated with conventional pathology findings, disease states, and clinical outcome.

Community-Based Evaluation of the Associations Between Well-Being and Cardiovascular Disease Risk.

Background Although the effects of psychological health and optimism have been extensively investigated, data from community-based cohorts assessing the association between psychological health and cardiovascular disease risk factors are sparse, and the concurrent relationship between subjective well-being and cardiovascular health has not been studied. Methods and Results The current cross-sectional study examined the association between well-being and cardiovascular risk factors among 719 individuals living in a middle- to low-income neighborhood. After adjusting for age, sex, race, body mass index, education, smoking status, and exercise status, we found that higher levels of well-being were significantly associated with lower odds of dyslipidemia (odds ratio [OR], 0.7 [95% CI, 0.55-0.85]) and hypertension (OR, 0.8 [95% CI, 0.63-0.92]). Greater well-being was also significantly associated with lower triglyceride levels (mean difference [Mdiff], 7.6 [-14.31 to -0.78]), very low-density lipoprotein (Mdiff, 0.9 [-1.71 to -0.16]), total cholesterol to high-density lipoprotein ratio (Mdiff, 3.9 [-6.07 to -1.73]), higher high-density lipoprotein levels (Mdiff, 1.6 [0.46-2.75]), and lower Framingham Risk Scores (Mdiff, -7.1% [-10.84% to -3.16%]). Well-being also moderated the association between age and arterial stiffness. The strongest association between arterial stiffness and age was found for those with the lowest well-being scores; there was no association between age and arterial stiffness at high levels of well-being. Conclusions In a community-based cohort, individuals reporting higher levels of well-being have lower odds of hypertension and dyslipidemia as well as lower rates of age-dependent increase in vascular stiffness. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT03670524.

Enzymatic and non-enzymatic conversion of cystamine to thiotaurine and taurine.

The disulfide-containing molecule cystamine and the thiosulfonate thiotaurine are of interest as therapeutics. Both are precursors of taurine, but the chemistry of their metabolism is not clear. The rates at which these molecules are metabolized is also unknown. The chemistry and rate constants have been determined for a process in which cystamine is converted in four reactions to thiotaurine. Cystamine is oxidized by diamine oxidase with a specificity constant comparable to other diamine substrates. The rapid hydrogen peroxide-mediated oxidation of cystaldimine yields reactive glyoxal and thiocysteamine, which quickly performs transsulfuration with hypotaurine. Thiotaurine reacts spontaneously with hydrogen peroxide to form taurine and sulfite, but it is 15-fold less reactive than hypotaurine as an antioxidant. An estimation of biological rates of reaction indicates that cystamine is likely to be oxidized by diamine oxidase in vivo, but its metabolic products will be diverted to molecules other than thiotaurine.

Unilateral vs Bilateral Supraglottoplasty: A Meta-analysis of Rates of Return to Surgery and Supraglottic Stenosis.

OBJECTIVE: To perform a systematic review with meta-analysis of data to determine the rates of repeat surgery and supraglottic stenosis in unilateral versus bilateral supraglottoplasty for laryngomalacia. DATA SOURCES: PubMed/Medline, Cochrane Central, Scopus, Google Scholar, Web of Science, and Embase. REVIEW METHODS: Databases were searched through January 30, 2018. Studies with unilateral or bilateral supraglottoplasty techniques for laryngomalacia were included. The need for repeat (revision or completion) surgery and rates of supraglottic stenosis were primary outcomes. Data were substratified and a meta-analysis performed. RESULTS: A total of 251 articles were reviewed, and 20 articles met inclusion criteria (1186 patients: 663 bilateral, 523 unilateral). Regarding the need to return to surgery, the rate of revision for bilateral surgery was 4.1%, compared to the revision and combined revision/completion rates for unilateral surgery which respectively were 1.1% (odds ratio [OR] 0.27; 95% CI 0.11-0.67; P = .002) and 18.0% (OR 5.16; 95% CI 3.31-8.06; P < .0001). The unilateral versus bilateral supraglottic stenosis rates were 0% versus 1.2% (P = .011). CONCLUSION: Unilateral supraglottoplasty has a significantly higher rate of repeat surgery, mainly attributed to contralateral surgery, when compared with bilateral supraglottoplasty. There is a small but statistically significant risk of supraglottic stenosis in bilateral procedures. The benefit of a unilateral procedure should be weighed against the cost of subjecting patients to a 4-fold increased risk of repeat surgery.

Effects of PACK guide training on the management of asthma and chronic obstructive pulmonary disease by primary care clinicians: a pragmatic cluster randomised controlled trial in Florianópolis, Brazil.

INTRODUCTION: The Practical Approach to Care Kit (PACK) guide was localised for Brazil, where primary care doctors and nurses were trained to use it. METHODS: Twenty-four municipal clinics in Florianópolis were randomly allocated to receive outreach training and the guide, and 24 were allocated to receive only the guide. 6666 adult patients with asthma or chronic obstructive pulmonary disease (COPD) were enrolled, and trial outcomes were measured over 12 months, using electronic medical records. The primary outcomes were composite scores of treatment changes and spirometry, and new asthma and COPD diagnosis rates. RESULTS: Asthma scores in 2437 intervention group participants were higher (74.8%, 20.4% and 4.8% with scores of 0, 1 and 2, respectively) than in 2633 control group participants (80.0%, 16.8% and 3.2%) (OR for higher score 1.32, 95% CI 1.08 to 1.61, p=0.006). Adjusted for asthma scores recorded in each clinic before training started, the OR was 1.24 (95% CI 1.03 to 1.50, p=0.022). COPD scores in 1371 intervention group participants (77.7%, 17.9% and 4.3% with scores of 0, 1 and 2) did not differ from those in 1181 control group participants (80.5%, 15.8% and 3.7%) (OR 1.21, 95% CI 0.94 to 1.55, p=0.142). Rates of new asthma and COPD diagnoses, and hospital admission, and indicators of investigation, diagnosis and treatment of comorbid cardiovascular disease, diabetes and depression, and tobacco cessation did not differ between trial arms. CONCLUSION: PACK training increased guideline-based treatment and spirometry for asthma but did not affect COPD or comorbid conditions, or diagnosis rates. TRIAL REGISTRATION: NCT02786030 (https://clinicaltrials.gov/).

Sex specific recruitment of a medial prefrontal cortex-hippocampal-thalamic system during context-dependent renewal of responding to food cues in rats.

Renewal, or reinstatement, of responding to food cues after extinction may explain the inability to resist palatable foods and change maladaptive eating habits. Previously, we found sex differences in context-dependent renewal of extinguished Pavlovian conditioned responding to food cues. Context-induced renewal involves cue-food conditioning and extinction in different contexts and the renewal of conditioned behavior is induced by return to the conditioning context (ABA renewal). Male rats showed renewal of responding while females did not. In the current study we sought to identify recruitment of key neural systems underlying context-mediated renewal and sex differences. We examined Fos induction within the ventromedial prefrontal cortex (vmPFC), hippocampal formation, thalamus and amygdala in male and female rats during the test for renewal. We found sex differences in vmPFC recruitment during renewal. Male rats in the experimental condition showed renewal of responding and had more Fos induction within the infralimbic and prelimbic vmPFC areas compared to controls that remained in the same context throughout training and testing. Females in the experimental condition did not show renewal or an increase in Fos induction. Additionally, Fos expression differed between experimental and control groups and between the sexes in the hippocampal formation, thalamus and amygdala. Within the ventral subiculum, the experimental groups of both sexes had more Fos compared to control groups. Within the dorsal CA1 and the anterior region of the paraventricular nucleus of the thalamus, in males, the experimental group had higher Fos induction, while both females groups had similar number of Fos-positive neurons. Within the capsular part of the central amygdalar nucleus, females in the experimental group had higher Fos induction, while males groups had similar amounts. The differential recruitment corresponded to the behavioral differences between males and females and suggests the medial prefrontal cortex-hippocampal-thalamic system is a critical site of sex differences during renewal of appetitive Pavlovian responding to food cues. These findings provide evidence for novel neural mechanisms underlying sex differences in food motivation and contextual processing in associative learning and memory. The results should also inform future molecular and translational work investigating sex differences and maladaptive eating habits.

Residual manifestations of hypercortisolemia following surgical treatment in a patient with Cushing syndrome.

CONTEXT: Cushing Syndrome is difficult to diagnose, and the comorbidities and persistent late effects of hypercortisolemia after treatment of the primary disease are challenging for the patient and the endocrinologist. OBJECTIVE: To report the case of a girl with obesity and hypertension, ultimately diagnosed with Cushing syndrome due to primary pigmented nodular adrenocortical disease. In this case, the complications of hypercortisolism persisted short term despite surgical intervention. PATIENT: A 4 year old morbidly obese African-American girl with developmental delay presented with hypertensive emergency in the ER and 18-month history of progressive weight gain. Her previous history included premature adrenarche, hypertension, seizures and a random high cortisol with suppressed ACTH. She was subsequently stabilized, and a diagnostic work-up persistently demonstrated elevated cortisol and suppressed ACTH. An abdominal MRI showed bilateral adrenal multinodular disease, consistent with multinodular hyperplasia of the adrenal glands. Based on these findings the patient underwent a bilateral adrenalectomy, which confirmed primary pigmented nodular adrenocortical disease. The patient had a complicated, protracted post-operative course requiring adjustment of therapy for persistent hypertension. Two months after surgery, she was readmitted to the Emergency Department with hyperpyrexia and hypertension and succumbed to the complications of sepsis. CONCLUSIONS AND OUTCOME: This case highlights the significant diagnostic and therapeutic challenges in treating children with Cushing syndrome. Resolution of the source of hypercortisolemia does not imply regression of hypertension or recovery of the immune system. Although the child underwent bilateral adrenalectomy, persistent consequences of prolonged severe hypercortisolism contributed to her death two months later.

Renewal of conditioned responding to food cues in rats: Sex differences and relevance of estradiol.

Cues associated with food can stimulate food anticipation, procurement, and consumption, independently of hunger. These and other behaviors driven by learned cues are persistent and can reappear after extinction, because the original learned associations continue to exist. Renewal, or reinstatement, of extinguished conditioned behavior may explain the inability to change maladaptive eating habits driven by food cues, similar to the mechanisms of drug use relapse. Here, we investigated sex differences in context-induced renewal of responding to food cues, and the role of estradiol in females in a Pavlovian conditioning preparation. We compared adult male and female rats because there is evidence for sex differences in learning and memory and in the control of feeding. Context-induced renewal involves conditioning and extinction in different contexts and the renewal of conditioned behavior is induced by return to the conditioning context ("ABA renewal"; experimental groups). Control groups remain in the same context during conditioning, extinction, and test. In Experiment 1, male and female rats were trained to associate a tone with food pellets during acquisition, and after extinction with tone only presentations, were tested for renewal of responding to the tone. Learning was assessed through the expression of the conditioned response, which included approach and activity directed at food receptacle (food cup behavior). Males and females learned the acquisition and extinction of tone-food associations similarly, but there were sex differences during renewal of the conditioned responses to the food cue. Males showed robust renewal of responding, while renewal in intact females was inconsistent. Males in the experimental group had significantly higher food cup behavior compared to males in the control group, while females in both groups showed similar levels of food cup behavior during the tone. In Experiment 2, we examined a potential role of estradiol in renewal, by comparing intact females with ovariectomized females with, and without, estradiol replacement. Rats in all groups acquired and extinguished tone-food associations similarly. During the test for renewal, the ovariectomized rats with estradiol replacement in the experimental group showed renewal of responding, evidenced by significantly higher food cup behavior compared to the control group. Intact and ovariectomized rats in the experimental groups had similar rates of food cup behavior as their corresponding control groups. These results provide novel evidence for sex differences and relevance of estradiol in renewal of responding to food cues and more broadly in contextual processing and appetitive associative learning, potentially relevant to maladaptive eating habits and eating disorders.

The cis-regulatory effect of an Alzheimer's disease-associated poly-T locus on expression of TOMM40 and apolipoprotein E genes.

BACKGROUND: We investigated the genomic region spanning the Translocase of the Outer Mitochondrial Membrane 40-kD (TOMM40) and Apolipoprotein E (APOE) genes, that has been associated with the risk and age of onset of late-onset Alzheimer's disease (LOAD) to determine whether a highly polymorphic, intronic poly-T within this region (rs10524523; hereafter, 523) affects expression of the APOE and TOMM40 genes. Alleles of this locus are classified as S, short; L, long; and VL, very long based on the number of T residues. METHODS: We evaluated differences in APOE messenger RNA (mRNA) and TOMM40 mRNA levels as a function of the 523 genotype in two brain regions from APOE ε3/ε3 white autopsy-confirmed LOAD cases and normal controls. We further investigated the effect of the 523 locus in its native genomic context using a luciferase expression system. RESULTS: The expression of both genes was significantly increased with disease. Mean expression of APOE and TOMM40 mRNA levels were higher in VL homozygotes compared with S homozygotes in the temporal and occipital cortexes from normal and LOAD cases. Results of a luciferase reporter system were consistent with the human brain mRNA analysis; the 523 VL poly-T resulted in significantly higher expression than the S poly-T. Although the effect of poly-T length on reporter expression was the same in HepG2 hepatoma and SH-SY5Y neuroblastoma cells, the magnitude of the effect was greater in the neuroblastoma than in the hepatoma cells, which implies tissue-specific modulation of the 523 poly-T. CONCLUSIONS: These results suggest that the 523 locus may contribute to LOAD susceptibility by modulating the expression of TOMM40 and/or APOE transcription.

mTORC2 modulates feedback regulation of p38 MAPK activity via DUSP10/MKP5 to confer differential responses to PP242 in glioblastoma.

Dual-specificity phosphatases (DUSPs) dephosphorylate MAP kinases (MAPKs) resulting in their inactivation. Activation of MAPK signaling leads to enhanced DUSP expression, thus establishing feedback regulation of the MAPK pathway. The DUSPs are subject to regulation at the post-translational level via phosphorylation resulting in alterations of protein stability. Here we report that mTORC2 function leads to stabilization of the p38 MAPK phosphatase, DUSP10, thereby inhibiting p38 activity. We demonstrate that mTORC2 binds DUSP10 and phosphorylates DUSP10 on serine residues 224 and 230. These phosphorylation events block DUSP10 turnover resulting in inactivation of p38 signaling. We further show that insulin-stimulated PI3K/mTORC2 signaling regulates DUSP10 stability and p38 activity. Importantly, knockdown of DUSP10 or ectopic overexpression of nonphosphorylatable or phosphomimetic DUSP10 mutants was sufficient to confer differential mTOR kinase inhibitor responses to GBM cells in vitro and in murine xenografts. Finally, DUSP10 was shown to be overexpressed in a significant number of GBM patients. These data demonstrate the ability of the mTORC2 pathway to exert regulatory effects on the DUSP10/p38 feedback loop to control the cellular effects of mTOR kinase inhibitors in GBM and support the use of DUSP10 expression as a surrogate biomarker to predict responsiveness.

The influence of radiation therapy on dental implantology.

Patients with a history of head and neck cancer resection require extensive prosthodontic rehabilitation following cancer treatment. The oral anatomy drastically changes from ablative therapy, and the oral tissue response becomes altered as a consequence of radiation and chemotherapy. Successful restoration of oral function in this specific patient population was increasingly difficult before the widespread use of dental implants. Implant-borne prosthetics are now often used. However, surgical guidelines remain unclear with regard to oncology-related parameters. In this article, guidelines are introduced for implant therapy in the cancer patients according to radiation dosage and timing. Indications for hyperbaric oxygen treatment are highlighted along with risk assessment associated with implant placement. These guidelines are intended to augment knowledge obtained through oncology consultation; moreover, provide a rationale for implant therapy within the course of cancer treatment.

ApolipoproteinE mimetic peptides improve outcome after focal ischemia.

Growing clinical evidence implicates isoform-specific effects of apolipoprotein E (apoE) in reducing neuroinflammation and mediating adaptive responses following ischemic and traumatic brain injury. However, the intact apoE holoprotein does not cross the blood-brain barrier and thus has limited therapeutic potential. We have created a small peptide, COG1410 (acetyl-AS-Aib-LRKL-Aib-KRLL-amide), derived from the apoE receptor-binding region. COG1410 retains the anti-inflammatory and neuroprotective biological properties of the intact holoprotein and penetrates the blood-brain barrier. In the current study, we utilized a murine model of transient focal cerebral ischemia and reperfusion to demonstrate that intravenous (IV) administration of COG1410 reduces infarct volume and radiographic progression of infarct, and improves functional outcome as assessed by rotarod when delivered up to 4h after ischemia onset.

Conditional astroglial Rictor overexpression induces malignant glioma in mice.

BACKGROUND: Hyperactivation of the mTORC2 signaling pathway has been shown to contribute to the oncogenic properties of gliomas. Moreover, overexpression of the mTORC2 regulatory subunit Rictor has been associated with increased proliferation and invasive character of these tumor cells. METHODOLOGY/PRINCIPAL FINDINGS: To determine whether Rictor overexpression was sufficient to induce glioma formation in mice, we inserted a Cre-lox-regulated human Rictor transgene into the murine ROSA26 locus. This floxed Rictor strain was crossed with mice expressing the Cre recombinase driven from the glial fibrillary acidic protein (GFAP) promoter whose expression is limited to the glial cell compartment. Double transgenic GFAP-Cre/Rictor(loxP/loxP) mice developed multifocal infiltrating glioma containing elevated mTORC2 activity and typically involved the subventricular zone (SVZ) and lateral ventricle. Analysis of Rictor-dependent signaling in these tumors demonstrated that in addition to elevated mTORC2 activity, an mTORC2-independent marker of cortical actin network function, was also elevated. Upon histological examination of the neoplasms, many displayed oligodendroglioma-like phenotypes and expressed markers associated with oligodendroglial lineage tumors. To determine whether upstream oncogenic EGFRvIII signaling would alter tumor phenotypes observed in the GFAP-Cre/Rictor(loxP/loxP) mice, transgenic GFAP-EGFRvIII; GFAP-Cre/Rictor(loxP/loxP) mice were generated. These mice developed mixed astrocytic-oligodendroglial tumors, however glioma formation was accelerated and correlated with increased mTORC2 activity. Additionally, the subventricular zone within the GFAP-Cre/Rictor(loxP/loxP) mouse brain was markedly expanded, and a further proliferation within this compartment of the brain was observed in transgenic GFAP-EGFRvIII; GFAP-Cre/Rictor(loxP/loxP) mice. CONCLUSION/SIGNIFICANCE: These data collectively establish Rictor as a novel oncoprotein and support the role of dysregulated Rictor expression in gliomagenesis via mTOR-dependent and mTOR-independent mechanisms. Furthermore, oncogenic EGFRvIII signaling appears to potentiate the in vivo proliferative capacity of GFAP-Cre/Rictor(loxP/loxP) gliomas.

Inhibition of SAPK2/p38 enhances sensitivity to mTORC1 inhibition by blocking IRES-mediated translation initiation in glioblastoma.

A variety of mechanisms confer hypersensitivity of tumor cells to the macrolide rapamycin, the prototypic mTORC1 inhibitor. Several studies have shown that the status of the AKT kinase plays a critical role in determining hypersensitivity. Cancer cells in which AKT activity is elevated are exquisitely sensitive to mTORC1 inhibitors while cells in which the kinase is quiescent are relatively resistant. Our previous work has shown that a transcript-specific protein synthesis salvage pathway is operative in cells with quiescent AKT levels, maintaining the translation of crucial mRNAs involved in cell-cycle progression in the face of global eIF-4E-mediated translation inhibition. The activation of this salvage pathway is dependent on SAPK2/p38-mediated activation of IRES-dependent initiation of the cyclin D1 and c-MYC mRNAs, resulting in the maintenance of their protein expression levels. Here, we show that both genetic and pharmacologic inhibition of SAPK2/p38 in glioblastoma multiforme cells significantly reduces rapamycin-induced IRES-mediated translation initiation of cyclin D1 and c-MYC, resulting in increased G(1) arrest in vitro and inhibition of tumor growth in xenografts. Moreover, we observed that the AKT-dependent signaling alterations seen in vitro are also displayed in engrafted tumors cells and were able to show that combined inhibitor treatments markedly reduced the mRNA translational state of cyclin D1 and c-MYC transcripts in tumors isolated from mice. These data support the combined use of SAPK2/p38 and mTORC1 inhibitors to achieve a synergistic antitumor therapeutic response, particularly in rapamycin-resistant quiescent AKT-containing cells.