Integrin-αvß6 targeted peptide-toxin therapy in a novel αvß6-expressing immunocompetent model of pancreatic cancer.

Previously we reported that a novel αvß6-specific peptide-drug conjugate (SG3299) could eliminate established human pancreatic ductal adenocarcinoma (PDAC) xenografts. However the development of effective therapies for PDAC, which is an essential need, must show efficacy in relevant immunocompetent animals. Previously we reported that the KPC mouse transgenic PDAC model that closely recapitulates most stages of development of human PDAC, unlike in humans, failed to express αvß6 on their tumours or metastases. In this study we have taken the KPC-derived PDAC line TB32043 and engineered a variant line (TB32043mb6S2) that expresses mouse integrin αvß6. We report that orthotopic implantation of the αvß6 over-expressing TB32043mb6S2 cells promotes shorter overall survival and increase in metastases. Moreover, systemic treatment of mice with established TB32043mb6S2 tumours in the pancreas with SG2399 lived significantly longer (p < 0.001; mean OS 48d) compared with PBS or control SG3511 (mean OS 25.5d and 26d, respectively). Thus SG3299 is confirmed as a promising candidate therapeutic for the therapy of PDAC.

Chronic TNF exposure induces glucocorticoid-like immunosuppression in the alveolar macrophages of aged mice that enhances their susceptibility to pneumonia.

Chronic low-grade inflammation, particularly elevated tumor necrosis factor (TNF) levels, occurs due to advanced age and is associated with greater susceptibility to infection. One reason for this is age-dependent macrophage dysfunction (ADMD). Herein, we use the adoptive transfer of alveolar macrophages (AM) from aged mice into the airway of young mice to show that inherent age-related defects in AM were sufficient to increase the susceptibility to Streptococcus pneumoniae, a Gram-positive bacterium and the leading cause of community-acquired pneumonia. MAPK phosphorylation arrays using AM lysates from young and aged wild-type (WT) and TNF knockout (KO) mice revealed multilevel TNF-mediated suppression of kinase activity in aged mice. RNAseq analyses of AM validated the suppression of MAPK signaling as a consequence of TNF during aging. Two regulatory phosphatases that suppress MAPK signaling, Dusp1 and Ptprs, were confirmed to be upregulated with age and as a result of TNF exposure both ex vivo and in vitro. Dusp1 is known to be responsible for glucocorticoid-mediated immune suppression, and dexamethasone treatment increased Dusp1 and Ptprs expression in cells and recapitulated the ADMD phenotype. In young mice, treatment with dexamethasone increased the levels of Dusp1 and Ptprs and their susceptibility to infection. TNF-neutralizing antibody reduced Dusp1 and Ptprs levels in AM from aged mice and reduced pneumonia severity following bacterial challenge. We conclude that chronic exposure to TNF increases the expression of the glucocorticoid-associated MAPK signaling suppressors, Dusp1 and Ptprs, which inhibits AM activation and increases susceptibility to bacterial pneumonia in older adults.

The Chalcidoidea bush of life: evolutionary history of a massive radiation of minute wasps.

Chalcidoidea are mostly parasitoid wasps that include as many as 500 000 estimated species. Capturing phylogenetic signal from such a massive radiation can be daunting. Chalcidoidea is an excellent example of a hyperdiverse group that has remained recalcitrant to phylogenetic resolution. We combined 1007 exons obtained with Anchored Hybrid Enrichment with 1048 ultra-conserved elements (UCEs) for 433 taxa including all extant families, >95% of all subfamilies, and 356 genera chosen to represent the vast diversity of the superfamily. Going back and forth between the molecular results and our collective knowledge of morphology and biology, we detected bias in the analyses that was driven by the saturation of nucleotide data. Our final results are based on a concatenated analysis of the least saturated exons and UCE datasets (2054 loci, 284 106 sites). Our analyses support an expected sister relationship with Mymarommatoidea. Seven previously recognized families were not monophyletic, so support for a new classification is discussed. Natural history in some cases would appear to be more informative than morphology, as illustrated by the elucidation of a clade of plant gall associates and a clade of taxa with planidial first-instar larvae. The phylogeny suggests a transition from smaller soft-bodied wasps to larger and more heavily sclerotized wasps, with egg parasitism as potentially ancestral for the entire superfamily. Deep divergences in Chalcidoidea coincide with an increase in insect families in the fossil record, and an early shift to phytophagy corresponds with the beginning of the "Angiosperm Terrestrial Revolution". Our dating analyses suggest a middle Jurassic origin of 174 Ma (167.3-180.5 Ma) and a crown age of 162.2 Ma (153.9-169.8 Ma) for Chalcidoidea. During the Cretaceous, Chalcidoidea may have undergone a rapid radiation in southern Gondwana with subsequent dispersals to the Northern Hemisphere. This scenario is discussed with regard to knowledge about the host taxa of chalcid wasps, their fossil record and Earth's palaeogeographic history.

Opposing roles for ADAMTS2 and ADAMTS14 in myofibroblast differentiation and function.

Crosstalk between cancer and stellate cells is pivotal in pancreatic cancer, resulting in differentiation of stellate cells into myofibroblasts that drives tumour progression. To assess cooperative mechanisms in a 3D context, we generated chimeric spheroids using human and mouse cancer and stellate cells. Species-specific deconvolution of bulk-RNA sequencing data revealed cell type-specific transcriptomes underpinning invasion. This dataset highlighted stellate-specific expression of transcripts encoding the collagen-processing enzymes ADAMTS2 and ADAMTS14. Strikingly, loss of ADAMTS2 reduced, while loss of ADAMTS14 promoted, myofibroblast differentiation and invasion independently of their primary role in collagen-processing. Functional and proteomic analysis demonstrated that these two enzymes regulate myofibroblast differentiation through opposing roles in the regulation of transforming growth factor ß availability, acting on the protease-specific substrates, Serpin E2 and fibulin 2, for ADAMTS2 and ADAMTS14, respectively. Showcasing a broader complexity for these enzymes, we uncovered a novel regulatory axis governing malignant behaviour of the pancreatic cancer stroma. © 2023 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

Dose frequency randomized controlled trial for Dynamic Temporal and Tactile Cueing (DTTC) treatment for childhood apraxia of speech: protocol paper.

BACKGROUND: Childhood apraxia of speech (CAS) is a pediatric motor-based speech sound disorder that requires a specialized approach to intervention. The extant literature on the treatment of CAS commonly recommends intensive treatment using a motor-based approach, with some of the best evidence supporting the use of Dynamic Temporal and Tactile Cueing (DTTC). To date, a rigorous and systematic comparison of high and low dose frequency (i.e., frequency of therapy sessions) has not been undertaken for DTTC, resulting in a lack of evidence to guide decisions about the optimal treatment schedule for this intervention. The current study aims to fill this gap in knowledge by comparing treatment outcomes when dose frequency is varied. METHODS: A randomized controlled trial will be conducted to examine the efficacy of low versus high dose frequency on DTTC treatment outcomes in children with CAS. A target of 60 children, 2;6-7;11 years of age, will be recruited to participate in this study. Treatment will be provided in the community setting by speech-language pathologists who have completed specialized training administering DTTC in a research reliable manner. True randomization with concealed allocation will be used to assign children to either the low or high dose frequency group. Treatment will be administered in 1-h sessions either 4 times per week over a 6-week period (high dose) or 2 times per week over a 12-week period (low dose). To measure treatment gains, probe data will be collected before treatment, during treatment, and 1 day, 1 week, 4 weeks, and 12 weeks post-treatment. Probe data will consist of customized treated words and a standard set of untreated words to assess generalization of treatment gains. The primary outcome variable will be whole word accuracy, encompassing segmental, phonotactic, and suprasegmental accuracy. DISCUSSION: This will be the first randomized controlled trial to evaluate dose frequency for DTTC treatment in children with CAS. TRIAL REGISTRATION: ClinicalTrials.gov identifier NCT05675306, January 6, 2023.

Implantation of engineered adipocytes that outcompete tumors for resources suppresses cancer progression.

Tumors acquire an increased ability to obtain and metabolize nutrients. Here, we engineered and implanted adipocytes to outcompete tumors for nutrients and show that they can substantially reduce cancer progression. Growing cells or xenografts from several cancers (breast, colon, pancreas, prostate) alongside engineered human adipocytes or adipose organoids significantly suppresses cancer progression and reduces hypoxia and angiogenesis. Transplanting modulated adipocyte organoids in pancreatic or breast cancer mouse models nearby or distal from the tumor significantly suppresses its growth. To further showcase therapeutic potential, we demonstrate that co-culturing tumor organoids derived from human breast cancers with engineered patient-derived adipocytes significantly reduces cancer growth. Combined, our results introduce a novel cancer therapeutic approach, termed adipose modulation transplantation (AMT), that can be utilized for a broad range of cancers.

Supportive care needs of men with prostate cancer: A systematic review update.

BACKGROUND: Prostate cancer is highly prevalent and impacts profoundly on patients' quality of life, leading to a range of supportive care needs. METHODS: An updated systematic review and thematic synthesis of qualitative data using the Preferred Reporting Items for Systematic Reviews (PRISMA) reporting guidelines, to explore prostate cancer patients' experience of, and need for, supportive care. Five databases (Medline, Embase, PsycInfo, Emcare and ASSIA) were searched; extracted data were synthesised using Corbin and Strauss's 'Three Lines of Work' framework. RESULTS: Searches identified 2091 citations, of which 105 were included. Overarching themes emerged under the headings of illness, everyday life and biographical work. Illness work needs include consistency and continuity of information, tailored to ethnicity, age and sexual orientation. Biographical work focused on a desire to preserve identity in the context of damaging sexual side effects. Everyday life needs centred around exercise and diet support and supportive relationships with partners and peers. Work-related issues were highlighted specifically by younger patients, whereas gay and bisexual men emphasised a lack of specialised support. CONCLUSION: While demonstrating some overarching needs common to most patients with prostate cancer, this review offers novel insight into the unique experiences and needs of men of different demographic backgrounds, which will enable clinicians to deliver individually tailored supportive care.

Disruption of pancreatic stellate cell myofibroblast phenotype promotes pancreatic tumor invasion.

In pancreatic ductal adenocarcinoma (PDAC), differentiation of pancreatic stellate cells (PSCs) into myofibroblast-like cancer-associated fibroblasts (CAFs) can both promote and suppress tumor progression. Here, we show that the Rho effector protein kinase N2 (PKN2) is critical for PSC myofibroblast differentiation. Loss of PKN2 is associated with reduced PSC proliferation, contractility, and alpha-smooth muscle actin (α-SMA) stress fibers. In spheroid co-cultures with PDAC cells, loss of PKN2 prevents PSC invasion but, counter-intuitively, promotes invasive cancer cell outgrowth. PKN2 deletion induces a myofibroblast to inflammatory CAF switch in the PSC matrisome signature both in vitro and in vivo. Further, deletion of PKN2 in the pancreatic stroma induces more locally invasive, orthotopic pancreatic tumors. Finally, we demonstrate that a PKN2KO matrisome signature predicts poor outcome in pancreatic and other solid human cancers. Our data indicate that suppressing PSC myofibroblast function can limit important stromal tumor-suppressive mechanisms, while promoting a switch to a cancer-supporting CAF phenotype.

The multidisciplinary, theory-based co-design of a new digital health intervention supporting the care of oesophageal cancer patients.

OBJECTIVE: Oesophageal cancer patients have complex care needs. Cancer clinical nurse specialists play a key role in coordinating their care but often have heavy workloads. Digital health interventions can improve patient care but there are few examples for oesophageal cancer. This paper aims to describe the multidisciplinary co-design process of a digital health intervention to improve the experience of care and reduce unmet needs among patients with oesophageal cancer. METHODS: A theory-based, multi-disciplinary, co-design approach was used to inform the developmental process of the digital health intervention. Key user needs were elicited using mixed methodology from systematic reviews, focus groups and interviews and holistic need assessments. Overarching decisions were discussed among a core team of patients, carers, health care professionals including oncologists and cancer clinical nurse specialists, researchers and digital health providers. A series of workshops incorporating a summary of findings of key user needs resulted in the development of a minimum viable product. This was further refined after a pilot study based on feedback from end users. RESULTS: The final digital health intervention consists of a mobile app feature for patients and carers connected to a dashboard with supporting additional features for clinical nurse specialist. It contains a one-way messaging function for clinical nurse specialists to communicate with patients, functions for patients to record weight and holistic need assessment results which could be viewed by their clinical nurse specialists as well as a library of informative articles. CONCLUSIONS: The multidisciplinary co-design of a digital health intervention providing support for oesophageal cancer patients and health care professionals has been described. Future studies to establish its impact on patient outcomes are planned.

Circulating syndecan-1 is reduced in pregnancies with poor fetal growth and its secretion regulated by matrix metalloproteinases and the mitochondria.

Fetal growth restriction is a leading cause of stillbirth that often remains undetected during pregnancy. Identifying novel biomarkers may improve detection of pregnancies at risk. This study aimed to assess syndecan-1 as a biomarker for small for gestational age (SGA) or fetal growth restricted (FGR) pregnancies and determine its molecular regulation. Circulating maternal syndecan-1 was measured in several cohorts; a large prospective cohort collected around 36 weeks' gestation (n = 1206), a case control study from the Manchester Antenatal Vascular service (285 women sampled at 24-34 weeks' gestation); two prospective cohorts collected on the day of delivery (36 + 3-41 + 3 weeks' gestation, n = 562 and n = 405 respectively) and a cohort who delivered for preterm FGR (< 34 weeks). Circulating syndecan-1 was consistently reduced in women destined to deliver growth restricted infants and those delivering for preterm disease. Syndecan-1 secretion was reduced by hypoxia, and its loss impaired proliferation. Matrix metalloproteinases and mitochondrial electron transport chain inhibitors significantly reduced syndecan-1 secretion, an effect that was rescued by coadministration of succinate, a mitochondrial electron transport chain activator. In conclusion, circulating syndecan-1 is reduced among cases of term and preterm growth restriction and has potential for inclusion in multi-marker algorithms to improve detection of poorly grown fetuses.

Circulating Growth Differentiation Factor 15 Is Increased Preceding Preeclampsia Diagnosis: Implications as a Disease Biomarker.

Background We investigated the biomarker potential of growth differentiation factor 15 (GDF-15), a stress response protein highly expressed in placenta, to predict preeclampsia. Methods and Results In 2 prospective cohorts (cohort 1: 960 controls, 39 women who developed preeclampsia; cohort 2: 950 controls, 41 developed preeclampsia), plasma concentrations of GDF-15 at 36 weeks' gestation were significantly increased among those who developed preeclampsia (P<0.001), area under the receiver operating characteristic curves (AUC) of 0.66 and 0.71, respectively. In cohort 2 a ratio of sFlt-1/PlGF (a clinical biomarker for preeclampsia) had a sensitivity of 61.0% at 83.2% specificity to predict those who will develop preeclampsia (AUC of 0.79). A ratio of GDF-15×sFlt-1/PlGF yielded a sensitivity of 68.3% at 83.2% specificity (AUC of 0.82). GDF-15 was consistently elevated across a number of international cohorts: levels were higher in placenta and blood from women delivering <34 weeks' gestation due to preterm preeclampsia in Melbourne, Australia; and in the blood at 26 to 32 weeks' gestation among 57 women attending the Manchester Antenatal Vascular Service (MAViS, UK) who developed preeclampsia (P=0.0002), compared with 176 controls. In the Preeclampsia Obstetric adVerse Events biobank (PROVE, South Africa), plasma GDF-15 was significantly increased in women with preeclampsia with severe features (P=0.02; n=14) compared to controls (n=14). Conclusions We conclude circulating GDF-15 is elevated among women more likely to develop preeclampsia or diagnosed with the condition. It may have value as a clinical biomarker, including the potential to improve the sensitivity of sFlt-1/PlGF ratio.

The cost impact of unselective vs selective MammaPrint testing in early-stage breast cancer in Southern Africa.

BACKGROUND: MammaPrint (MP) has been applied in South Africa (SA) for decision-making in early-stage hormone receptor-positive breast cancer since 2006. The cost-impact of MP in SA has not been assessed. AIM: To assess different MP testing strategies for cost-minimization in early-stage breast carcinoma using a funder perspective. METHODS: Clinico-pathologic information was extracted from a prospectively collected database. Clinical risk stratification was done using Adjuvant Online! (AOL) and the Predict V2.1 algorithm (www.predict.nhs.uk). An unselected MP testing strategy was compared to a selective strategy, testing only clinically high risk (cHigh) patients. Excluding human epidermal growth factor receptor-2 positive tumours, the costs for chemotherapy treatment and MP using funding data were used to evaluate the financial impact of these strategies. RESULTS: In 583 patients with 601 tumours, 52% were clinically low risk (cLow) (AOL) while the average Predict 10-year survival with chemotherapy was 2.9%. MP correlated strongly with Predict and 318 (60%) patients were MP low risk. Unselective testing allowed omission of chemotherapy in 44 (8.4%) patients but escalated cost by 57.7%. Using a selective testing strategy, only 251 would be tested, de-escalating treatment in 138 (55%) and reducing cost by 19.5%. Considering a Predict value up to 3.2% as cHigh, cost would be up to 7.3% (p = 0.0467) lower with a selective testing strategy. CONCLUSION: MP allowed reduction in the use of adjuvant chemotherapy. Unselective use of MP increases overall costs. A selective testing strategy through clinical risk stratification using AOL/Predict results in substantial cost saving.

The Supportive Care Needs of Cancer Patients: a Systematic Review.

Cancer, and the complex nature of treatment, has a profound impact on lives of patients and their families. Subsequently, cancer patients have a wide range of needs. This study aims to identify and synthesise cancer patients' views about areas where they need support throughout their care. A systematic  search of the literature from PsycInfo, Embase and Medline databases was conducted, and a narrative. Synthesis of results was carried out using the Corbin & Strauss "3 lines of work" framework. For each line of work, a group of key common needs were identified. For illness-work, the key needs idenitified were; understanding their illness and treatment options, knowing what to expect, communication with healthcare professionals, and staying well. In regards to everyday work, patients wanted to maintain a sense of normalcy and look after their loved ones. For biographical work, patients commonly struggled with the emotion impact of illness and a lack of control over their lives. Spiritual, sexual and financial problems were less universal. For some types of support, demographic factors influenced the level of need reported. While all patients are unique, there are a clear set of issues that are common to a majority of cancer journeys. To improve care, these needs should be prioritised by healthcare practitioners.

Procalcitonin Differs in Children With Infection and Children With Disease Flares in Juvenile Idiopathic Arthritis.

BACKGROUND/OBJECTIVE: Patients with juvenile idiopathic arthritis (JIA) often present with signs and symptoms suggestive of serious bacterial infection (SBI). Procalcitonin (PCT) is a biomarker that is elevated in SBI. We conducted a comparative cohort study to test the hypothesis that PCT levels will differ between active JIA, quiescent JIA, and bacteremic patients and healthy controls. METHODS: From October 2016 to May2018, consecutive children 6 months to 18 years of age with (a) active untreated JIA, (b) quiescent JIA, and (c) healthy elective presurgical candidates were recruited from clinics at a musculoskeletal specialty hospital. Juvenile idiopathic arthritis was defined according to the International League of Associations for Rheumatology criteria. Clinical data and serum samples meeting the same criteria were included from a prior study. Consecutive bacteremic patients were identified over the same period. Procalcitonin and other common measures of inflammation were measured. Descriptive statistics and univariate logistic analyses were performed. RESULTS: Ninety-two study subjects were recruited. Erythrocyte sedimentation rate, C-reactive protein (CRP), and PCT levels were all elevated in bacteremic patients in comparison to the other groups. Erythrocyte sedimentation rate and CRP both had wide ranges that overlapped between groups; however, the PCT concentration was 0.15 µg/mL or greater in 1 of 59 patients with JIA, whereas it was 0.15 µg/mL or less in only 1 bacteremic patient. CONCLUSIONS: Our study indicates that serum erythrocyte sedimentation rate, CRP, and PCT levels are all biomarkers that can be used to distinguish SBI versus active JIA at presentation. However, PCT is the most accurate, with the least overlap between patients with infection and noninfectious inflammatory arthritis. This finding can help clinicians direct therapy.

Integrin αvß6-specific therapy for pancreatic cancer developed from foot-and-mouth-disease virus.

Goals of investigation: The 5-year survival rate for pancreatic ductal adenocarcinoma (PDAC) has remained at <5% for decades because no effective therapies have been identified. Integrin αvß6 is overexpressed in most PDAC and represents a promising therapeutic target. Thus, we attempted to develop an αvß6-specific peptide-drug conjugate (PDC) for therapy of PDAC. Methodology: We conjugated the DNA-binding pyrrolobenzodiazepine (PBD)-based payload SG3249 (tesirine) to an αvß6-specific 20mer peptide from the VP1 coat protein of foot-and-mouth-disease virus (FMDV) (forming conjugate SG3299) or to a non-targeting peptide (forming conjugate SG3511). PDCs were tested for specificity and toxicity on αvß6-negative versus-positive PDAC cells, patient-derived cell lines from tumor xenografts, and on two different in vivo models of PDAC. Immunohistochemical analyses were performed to establish therapeutic mechanism. Results: The αvß6-targeted PDC SG3299 was significantly more toxic (up to 78-fold) for αvß6-expressing versus αvß6-negative PDAC cell lines in vitro, and achieved significantly higher toxicity at equal dose than the non-targeted PDC SG3511 (up to 15-fold better). Moreover, SG3299 eliminated established (100mm3) Capan-1 PDAC human xenografts, extending the lifespan of mice significantly (P=0.005). Immunohistochemistry revealed SG3299 induced DNA damage and apoptosis (increased γH2AX and cleaved caspase 3, respectively) associated with significant reductions in proliferation (Ki67), ß6 expression and PDAC tumour growth. Conclusions: The FMDV-peptide drug conjugate SG3299 showed αvß6-selectivity in vitro and in vivo and can specifically eliminate αvß6-positive cancers, providing a promising new molecular- specific therapy for pancreatic cancer.

Relative Fundamental Frequency in Children With and Without Vocal Fold Nodules.

Purpose Relative fundamental frequency (RFF) is an acoustic measure that is sensitive to functional voice differences in adults. The aim of the current study was to evaluate RFF in children, as there are known structural and functional differences between the pediatric and adult vocal mechanisms. Method RFF was analyzed in 28 children with vocal fold nodules (CwVN, M = 9.0 years) and 28 children with typical voices (CwTV, M = 8.9 years). RFF is the instantaneous fundamental frequency (f 0) of the 10 vocalic cycles during devoicing (vocal offset) and 10 vocalic cycles during the revoicing (vocal onset) of the vowels that surround a voiceless consonant. Each cycle's f 0 was normalized to a steady-state portion of the vowel. RFF values for the cycles closest to the voiceless consonant, that is, Offset Cycle 10 and Onset Cycle 1, were examined. Results Average RFF values for Offset Cycle 10 and Onset Cycle 1 did not differ between CwVN and CwTV; however, within-subject variability of Offset Cycle 10 was decreased in CwVN. Across both groups, male children had lower Offset Cycle 10 RFF values as compared to female children. Additionally, Onset Cycle 1 values were decreased in younger children as compared to those of older children. Conclusions Unlike previous work with adults, CwVN did not have significantly different RFF values than CwTV. Younger children had lower RFF values for Onset Cycle 1 than older children, suggesting that vocal onset f 0 may provide information on the maturity of the laryngeal motor system.

Improving Quality of Radiation Therapy Care Across Ontario using a Community-of-Practice Approach.

PURPOSE: In 2003 and 2004, Cancer Care Ontario (CCO) divested its assets and staff to regional hospitals, leading to decreased contact between radiation therapy departments across Ontario's Regional Cancer Centres (RCCs). The Radiation Treatment Program (RTP) at CCO developed a communities-of-practice (CoPs) program to rebuild the provincial radiation therapy community to facilitate collaboration among centers, with the goals of decreasing variation in practice and improving the quality of patient care. RTP's CoPs are led and driven by volunteer frontline health care practitioners who identify and prioritize key quality issues and select corresponding projects to pursue. METHODS AND MATERIALS: An evaluation of RTP's CoPs was conducted to assess whether they were successful in knowledge creation, knowledge transfer and exchange, and community building. The framework was developed based on the Centers for Disease Control and Prevention CoP evaluation framework and tools. Data were collected using prospectively administered member surveys (257 surveys), publications, and semistructured interviews (18 participants). RESULTS: A total of 95% of participants reported that CoP projects were very relevant to their practice, and 50% reported changes in their practice stemming from CoP involvement. In addition, 90% of participants reported growth of their professional network as a result of CoPs. Overall, 93% of participants and 100% of interviewees reported that CoPs are a worthwhile initiative. The largest challenge of CoPs was the time commitment required to participate. CONCLUSIONS: This approach of member-driven CoPs should be explored and modeled in other health care settings as a means to develop and share knowledge to reduce variation in care and improve the quality of radiation therapy care.

Uncoupling TORC2 from AGC kinases inhibits tumour growth.

Mammalian target of rapamycin (mTOR) is a central regulator of growth and metabolism. mTOR resides in two distinct multi-protein complexes - mTORC1 and mTORC2 - with distinct upstream regulators and downstream targets. While it is possible to specifically inhibit mTORC1 with rapamycin, or inhibit both mTOR complexes together with ATP pocket directed mTOR kinase inhibitors, it is not possible to assess the specific roles for mTORC2 pharmacologically. To overcome this, we have developed a novel, inducible, dominant negative system for disrupting substrate recruitment to mTORC2. Previously we identified the mTORC2 specific subunit Sin1 as a direct binding partner for AGC kinases Akt and PKC. Sin1 mutants, which retain the ability to bind Rictor and mTOR, but fail to recruit their AGC client kinases, inhibit AKT and PKC priming and block cell growth. In this study, we demonstrate that uncoupling mTORC2 from AGC kinases in DLD1 colon cancer cells inhibits Akt activation and blocks tumour growth in vivo. Further we demonstrate, using time resolved two-site amplified FRET (A-FRET) analysis of xenograft tumours, that inhibition of tumour growth correlates with the degree of mTORC2 uncoupling from its downstream targets, as demonstrated for Akt. These data add weight to the body of evidence that mTORC2 represents a pharmacological target in cancer independently of mTORC1.

Actomyosin and vimentin cytoskeletal networks regulate nuclear shape, mechanics and chromatin organization.

The regulation of nuclear state by the cytoskeleton is an important part of cellular function. Actomyosin stress fibres, microtubules and intermediate filaments have distinct and complementary roles in integrating the nucleus into its environment and influencing its mechanical state. However, the interconnectedness of cytoskeletal networks makes it difficult to dissect their individual effects on the nucleus. We use simple image analysis approaches to characterize nuclear state, estimating nuclear volume, Poisson's ratio, apparent elastic modulus and chromatin condensation. By combining them with cytoskeletal quantification, we assess how cytoskeletal organization regulates nuclear state. We report for a number of cell types that nuclei display auxetic properties. Furthermore, stress fibres and intermediate filaments modulate the mechanical properties of the nucleus and also chromatin condensation. Conversely, nuclear volume and its gross morphology are regulated by intracellular outward pulling forces exerted by myosin. The modulation exerted by the cytoskeleton onto the nucleus results in changes that are of similar magnitude to those observed when the nucleus is altered intrinsically, inducing chromatin decondensation or cell differentiation. Our approach allows pinpointing the contribution of distinct cytoskeletal proteins to nuclear mechanical state in physio- and pathological conditions, furthering our understanding of a key aspect of cellular behaviour.