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SOS1 is one of the major guanine nucleotide exchange factors that regulates the ability of KRAS to cycle through its "on" and "off" states. Disrupting the SOS1:KRAS

ObjectiveTo introduce the Community Resiliency Model (CRM) as mental well-being support for healthcare workers working through the height of the COVID-19 pandemic.DesignRandomised controlled trial with a no treatment control group.SettingTwo large urban health systems in the Southern United States between October 2020 and June 2021.ParticipantsEligible participants were currently employed as healthcare workers within the participating healthcare systems. 275 employees registered and consented electronically in response to email invitations. 253 participants completed the baseline survey necessary to be randomised and included in analyses.InterventionParticipants were assigned 1:1 to the control or intervention group at the time of registration. Intervention participants were then invited to 1-hour virtual CRM class teaching skills to increase somatic awareness in the context of self and other care.Main outcome measuresSelf-reported data were collected rating somatic awareness, well-being, symptoms of stress, work engagement and interprofessional teamwork.ResultsBaseline data on the total sample of 275 (53% nurses) revealed higher symptoms of stress and lower well-being than the general population. The intervention participants who attended a CRM class (56) provided follow-up survey data at 1 week (44) and 3 months (36). Significant improvement for the intervention group at 3 months was reported for the well-being measures (WHO-5, pConclusionBaseline results indicate mental health is a concern for healthcare workers. Post intervention findings suggest that CRM is a practical approach to support well-being for healthcare workers during a crisis such as this pandemic. The simple tools that comprise the model can serve as a starting point for or complement self-care strategies to enhance individual resilience and buffer the effects of working in an increasingly stressful work environment.

MRTX1719 is an inhibitor of the PRMT5/MTA complex and recently entered clinical trials for the treatment of MTAP-deleted cancers. MRTX1719 is a class 3 atropisomeric compound that requires a chiral synthesis or a chiral separation step in its preparation. Here, we report the SAR and medicinal chemistry design strategy, supported by structural insights from X-ray crystallography, to discover a class 1 atropisomeric compound from the same series that does not require a chiral synthesis or a chiral separation step in its preparation.

The PRMT5•MTA complex has recently emerged as a new synthetically lethal drug target for the treatment of

Recent progress in targeting KRAS

KRAS

This publication details the successful use of FBDD (fragment-based drug discovery) principles in the invention of a novel covalent Bruton's tyrosine kinase inhibitor, which ultimately became the Takeda Pharmaceuticals clinical candidate TAK-020. Described herein are the discovery of the fragment 5-phenyl-2,4-dihydro-3

BACKGROUND: Clinical trials of the KRAS inhibitors adagrasib and sotorasib have shown promising activity in cancers harboring KRAS glycine-to-cysteine amino acid substitutions at codon 12 (KRAS(G12C)). The mechanisms of acquired resistance to these therapies are currently unknown. METHODS: Among patients with KRAS(G12C)-mutant cancers treated with adagrasib monotherapy, we performed genomic and histologic analyses that compared pretreatment samples with those obtained after the development of resistance. Cell-based experiments were conducted to study mutations that confer resistance to KRAS(G12C) inhibitors. RESULTS: A total of 38 patients were included in this study: 27 with non–small-cell lung cancer, 10 with colorectal cancer, and 1 with appendiceal cancer. Putative mechanisms of resistance to adagrasib were detected in 17 patients (45% of the cohort), of whom 7 (18% of the cohort) had multiple coincident mechanisms. Acquired KRAS alterations included G12D/R/V/W, G13D, Q61H, R68S, H95D/Q/R, Y96C, and high-level amplification of the KRAS(G12C) allele. Acquired bypass mechanisms of resistance included MET amplification; activating mutations in NRAS, BRAF, MAP2K1, and RET; oncogenic fusions involving ALK, RET, BRAF, RAF1, and FGFR3; and loss-of-function mutations in NF1 and PTEN. In two of nine patients with lung adenocarcinoma for whom paired tissue-biopsy samples were available, histologic transformation to squamous-cell carcinoma was observed without identification of any other resistance mechanisms. Using an in vitro deep mutational scanning screen, we systematically defined the landscape of KRAS mutations that confer resistance to KRAS(G12C) inhibitors. CONCLUSIONS: Diverse genomic and histologic mechanisms impart resistance to covalent KRAS(G12C) inhibitors, and new therapeutic strategies are required to delay and overcome this drug resistance in patients with cancer. (Funded by Mirati Therapeutics and others; ClinicalTrials.gov number, NCT03785249.)

COVID-19 is an established threat whose clinical features and epidemiology continues to evolve. In an effort to contain the disease, the National Health Service has adopted a digital first approach in UK general practice resulting in a significant shift away from face-to-face consultations. Consequently, more consultations are being completed without obtaining objective recording of vital signs and face-to-face examination. Some regions have formed hot hubs to facilitate the review of suspected COVID-19 cases and keep their practice site ‘clean’ including the use of doorstep observations in avoiding the risk of face-to-face examination. To support the safe, effective and efficient remote assessment of suspected and confirmed patients with COVID-19, we established a doorstep assessment service to compliment telephone and video consultations. This allows physiological parameters such as temperature, pulse, blood pressure and oxygen saturation to be obtained to guide further triage. Quality improvement methods were used to integrate and optimise the doorstep assessment and measure the improvements made. The introduction of a doorstep assessment service increased the proportion of assessments for patients with suspected COVID-19 in routine care over weeks. At the same time we were able to dramatically reduce face-to-face assessment over a 6-week period by optimising through a range of measures including the introduction of a digital stethoscope. The majority of patients were managed by their own general practitioner following assessment supporting continuity of care. There were no adverse events during the period of observation; no staff absences related to COVID-19. Quality improvement methods have facilitated the successful integration of doorstep assessments into clinical care.

PURPOSE: Most metastatic melanoma patients show variable responses to radiotherapy and do not benefit from immune checkpoint inhibitors (ICIs). Improved strategies for combination therapy that leverage potential benefits from radiotherapy and ICI are critical. METHODS AND MATERIALS: We analyzed metastatic melanoma tumors in the TCGA cohort for expression of genes coding for subunits of Type-A γ-aminobutyric acid (GABA) receptor (GABA(A)R), a chloride ion channel and major inhibitory neurotransmitter receptor. Electrophysiology was used to determine if melanoma cells possess intrinsic GABA(A)R activity. Melanoma cell viability studies were conducted to test if enhancing GABA(A)R mediated chloride transport using a benzodiazepine impaired viability. While a syngeneic melanoma mouse model was used to assay the effect of benzodiazepine on tumor volume and its ability to potentiate radiation and/or immunotherapy. Treated tumors were analyzed for changes in gene expression by RNA sequencing and presence of tumor infilitrating lymphocytes by flow cytometry. RESULTS: Genes coding for subunits of GABA(A)Rs express functional GABA(A)Rs in melanoma cells. By enhancing GABA(A)R mediated anion transport, benzodiazepines depolarize melanoma cells and impair their viability. In vivo, benzodiazepine alone reduces tumor growth and potentiates radiotherapy and α-PD-L1 anti-tumor activity. Combination of benzodiazepine, radiotherapy, and α-PD-L1 results in near complete regression of treated tumors and a potent abscopal effect, mediated by increased infiltration of polyfunctional CD8+ T cells. Treated tumors show expression of cytokine:cytokine receptor interactions and overrepresentation of p53 signaling. CONCLUSIONS: This study identifies an anti-tumor strategy combining radiation and/or immune checkpoint inhibitor with modulation of GABA(A)Rs in melanoma using a benzodiazepine.

Small interfering RNA (siRNA) is a critical loss-of-function tool for elucidating the role of genes in biomedical studies. The effective use of siRNA needs transfection technology that delivers siRNA into the correct location of target cells, especially those which are extremely difficult to transfect. Macrophages, which play an important role in the pathogenesis of many diseases, are known to be extremely hard to transfect. Thus, to elucidate the functions of genes in human macrophage biology, it is essential to devise technology for efficient siRNA transfection. However, a fast and efficient method for siRNA transfection in primary human macrophages has not been reported. The siRNA transfection is a tug-of-war between transfection rate and cytotoxicity. A higher transfection rate is generally accompanied with increased cytotoxicity, therefore, choosing a transfection reagent that limits cell death while maintain a desirable transfection rate is important. In this study, we employed auto-analysis function of the IncuCyte® to devise a fast and cost-saving technology for efficient transfection of adherent cells and particularly human macrophages. We show that DharmaFECT3 transfection reagent from Dharmacon was the most efficient in transfecting primary human monocyte-derived macrophages and PMA-differentiated U937 cells, whereas other transfection reagents tested were cytotoxic. This method exhibited approximately 85% transfection efficiency in human macrophages. Moreover, siRNA silencing of Bax with this technique effectively protected primary human macrophages and PMA-differentiated U937 cells against Resveratrol-induced cell death. In addition, this method inherently takes the balance between transfection rate and cytotoxicity of siRNA transfection reagents into consideration.

S-adenosylhomocysteine hydrolase (AHCY) catalyzes the reversible hydrolysis of S-adenosylhomocysteine (SAH) to adenosine and l-homocysteine. This enzyme is frequently overexpressed in many tumor types and is considered to be a validated anti-tumor target. In order to enable the development of small molecule AHCY inhibitors as targeted cancer therapeutics we developed an assay based on a RapidFire high-throughput mass spectrometry detection system, which allows the direct measurement of AHCY enzymatic activity. This technique avoids many of the problems associate with the previously reported method of using a thiol-reactive fluorescence probes to measure AHCY activity. Screening of a ∼500,000 compound library using this technique identified multiple SAH competitive hits. Co-crystal structures of the hit compounds complexed with AHCY were obtained showing that the compounds indeed bind in the SAH site of the enzyme. In addition, some hit compounds increased the SAH levels in HCT116 cells and showed growth inhibition. These compounds could be promising starting points for the optimization of cancer treatments.

Receptor tyrosine kinase therapies have proven to be efficacious in specific cancer patient populations; however, a significant limitation of tyrosine kinase inhibitor (TKI) treatment is the emergence of resistance mechanisms leading to a transient, partial, or complete lack of response. Combination therapies using agents with synergistic activity have potential to improve response and reduce acquired resistance. Chemoreagent or TKI treatment can lead to increased expression of hepatocyte growth factor (HGF) and/or MET, and this effect correlates with increased metastasis and poor prognosis. Despite MET's role in resistance and cancer biology, MET TKI monotherapy has yielded disappointing clinical responses. In this study, we describe the biological activity of a selective, oral MET TKI with slow off-rate and its synergistic antitumor effects when combined with an anti-HGF antibody. We evaluated the combined action of simultaneously neutralizing HGF ligand and inhibiting MET kinase activity in two cancer xenograft models that exhibit autocrine HGF/MET activation. The combination therapy results in additive antitumor activity in KP4 pancreatic tumors and synergistic activity in U-87MG glioblastoma tumors. Pharmacodynamic characterization of biomarkers that correlate with combination synergy reveal that monotherapies induce an increase in the total MET protein, whereas combination therapy significantly reduces total MET protein levels and phosphorylation of 4E-BP1. These results hold promise that dual targeting of HGF and MET by combining extracellular ligand inhibitors with intracellular MET TKIs could be an effective intervention strategy for cancer patients who have acquired resistance that is dependent on total MET protein. Mol Cancer Ther; 16(7); 1269–78. ©2017 AACR.

A series of potent ALK5 inhibitors were designed using a SBDD approach and subsequently optimized to improve drug likeness. Starting with a 4-substituted quinoline screening hit, SAR was conducted using a ALK5 binding model to understand the binding site and optimize activity. The resulting inhibitors displayed excellent potency but were limited by high in vitro clearance in rat and human microsomes. Using a scaffold morphing strategy, these analogs were transformed into a related pyrazolo[4,3-b]pyridine series with improved ADME properties.

Using SBDD, a series of 4-amino-7-azaindoles were discovered as a novel class of Alk5 inhibitors that are potent in both Alk5 enzymatic and cellular assays. Subsequently a ring cyclization strategy was utilized to improve ADME properties leading to the discovery of a series of 1H-imidazo[4,5-c]pyridin-2(3H)-one drug like Alk5 inhibitors.

Methionine aminopeptidase 2 (MetAP2) is an enzyme that cleaves an N-terminal methionine residue from a number of newly synthesized proteins. Pre-clinical and clinical studies suggest that MetAP2 inhibitors could be used as a novel treatment for obesity. Herein we describe our use of fragment screening methods and structural biology to quickly identify and elaborate an indazole fragment into a series of reversible MetAP2 inhibitors with

Myocardial infarct (MI) size is a well-established prognostic marker but the association of serum markers with MI size, as measured by myocardial perfusion imaging (MPI), has not been well studied in patients with hypertrophic cardiomyopathy (HC) after alcohol septal ablation (ASA). Creatine kinase (CK), CK-MB, troponin I, and brain natriuretic peptide were measured before and at multiple points after ASA in patients with HC and were correlated with MI size measured by MPI. MPI at rest was performed in 54 patients with HC at a median of 2 days after ASA. CK, CK-MB, and troponin I increased after ASA to peak levels at 12 hours and their cumulative levels (area under the curve) showed significant correlation with size of MI by MPI (r = 0.544, 0.408, and 0.477, p

The MAPK signaling cascade, comprised of several linear and intersecting pathways, propagates signaling into the nucleus resulting in cytokine and chemokine release. The Map Kinase Kinase isoforms 3 and 6 (MKK3 and MKK6) are responsible for the phosphorylation and activation of p38, and are hypothesized to play a key role in regulating this pathway without the redundancy seen in downstream effectors. Using FBDD, we have discovered efficient and selective inhibitors of MKK3 and MKK6 that can serve as tool molecules to help further understand the role of these kinases in MAPK signaling, and the potential impact of inhibiting kinases upstream of p38.

We present a case report of a 61-year-old gentleman who had a cardiac arrest and was delivered cardiopulmonary resuscitation (CPR) by a bystander. After resuscitation, he regained cardiac output and was breathing spontaneously. CT scan of the head showed spontaneous right frontal extradural aerocele with fracture of the posterior wall of the frontal sinus with no sign of head injury. We discuss the pathophysiology of this unrecognised complication due to CPR.

The number of intrinsically disordered proteins known to be involved in cell-signaling and regulation is growing rapidly. To test for a generalized involvement of intrinsic disorder in signaling and cancer, we applied a neural network predictor of natural disordered regions (PONDR VL-XT) to four protein datasets: human cancer-associated proteins (HCAP), signaling proteins (AfCS), eukaryotic proteins from SWISS-PROT (EU_SW) and non-homologous protein segments with well-defined (ordered) 3D structure (O_PDB_S25). PONDR VL-XT predicts >or=30 consecutive disordered residues for 79(+/-5)%, 66(+/-6)%, 47(+/-4)% and 13(+/-4)% of the proteins from HCAP, AfCS, EU_SW, and O_PDB_S25, respectively, indicating significantly more intrinsic disorder in cancer-associated and signaling proteins as compared to the two control sets. The disorder analysis was extended to 11 additional functionally diverse categories of human proteins from SWISS-PROT. The proteins involved in metabolism, biosynthesis, and degradation together with kinases, inhibitors, transport, G-protein coupled receptors, and membrane proteins are predicted to have at least twofold less disorder than regulatory, cancer-associated and cytoskeletal proteins. In contrast to 44.5% of the proteins from representative non-membrane categories, just 17.3% of the cancer-associated proteins had sequence alignments with structures in the Protein Data Bank covering at least 75% of their lengths. This relative lack of structural information correlated with the greater amount of predicted disorder in the HCAP dataset. A comparison of disorder predictions with the experimental structural data for a subset of the HCAP proteins indicated good agreement between prediction and observation. Our data suggest that intrinsically unstructured proteins play key roles in cell-signaling, regulation and cancer, where coupled folding and binding is a common mechanism.

This study examined whether estrogen replacement therapy (ERT) in postmenopausal women impacts intermediate and long-term outcome after successful coronary stenting. Our findings offer evidence that ERT significantly reduces target lesion revascularization after intracoronary stenting in postmenopausal patients who are on ERT before the intervention.

Behavioral and family characteristics of sexually aggressive children were obtained from a national convenience sample of treatment providers to gain descriptive data and to investigate the tentative use of a social learning theory model of sexual aggression of children. One hundred fifty-five professionals responded to a questionnaire of their work with a total of 287 sexually aggressive children aged 12 and under. A number of family variables may have impacted the children's sexual behavior. The average child resided in a two-parent home, and in most of these families (70%), at least one caretaker was chemically dependent; 48% have at least one parent known to have been sexually abused; and 72% of the children were sexually abused themselves (60% by a caretaker). The children with known sexual abuse histories were younger at first sign of sexual aggression than those without known sexual abuse histories. Children under 6 years of age were more likely to perceive their sexually aggressive behavior as normal than were older children. Differences based on gender of the children were not found for sexual aggression. These results suggest the potential for use of a social learning theory with sexual aggression in children. Implications for practice and suggestions for further research are discussed.

Although alcohol septal ablation (ASA) is increasingly used in hypertrophic cardiomyopathy (HC) patients who are refractory to medical therapy, the amount of alcohol that is required has not been well studied. This study sought to determine the amount of alcohol that is necessary to achieve clinical benefits of ASA.Myocardial perfusion imaging was used to determine the size of the myocardial infarction produced by ASA in 54 HC patients. Left ventricular outflow gradients (LVOTg) were determined invasively before and after ASA and by Doppler echocardiography before and at a median of 3 months after ASA.LVOTg decreased at rest and after provocation in response to ASA and this was maintained on follow-up at 3 months. There was no relationship between the amount of alcohol infused and the infarct mass as determined by myocardial perfusion imaging. While the infarct mass was not correlated with the drop in the LVOTg at rest or with provocation, the quantity of alcohol infused was correlated with the drop in LVOTg at rest (r = 0.27, p = 0.05) and with provocation (r = 0.34, p = 0.02). Furthermore, infusing more than 2ml of absolute alcohol was associated with a drop in the LVOTg by more than 60 mmHg at rest (p = 0.02) and by more than 130 mmHg with provocation (p = 0.05).Although lower amounts of alcohol infusion are desirable to avoid side-effects, it might be prudent to infuse around 2 ml of absolute alcohol in order to achieve the desirable degree of LVOTg reduction in ASA.

Alcohol septal ablation (ASA) as a treatment for obstructive hypertrophic cardiomyopathy produces septal infarction. There is a concern that such infarcts could be detrimental. Changes in the size of these infarcts by serial perfusion testing have not been studied. We performed resting serial-gated single-photon emission computed tomographic myocardial perfusion imaging in 30 patients (age 51+/-17 years, 57% were women) who had ASA between September 2003 and March 2007 before, 2+/-0.8 days (early), and 8.4+/-6.9 months (late) after ASA. Patients were also followed clinically and with serial 2-dimensional echocardiography. New York Heart Association class decreased from 3.50+/-0.51 before to 1.14+/-0.36 (p0.0001) 3 months after ASA. The left ventricular (LV) outflow gradient (by Doppler echocardiography) decreased from 63+/-32 mm Hg before to 28+/-23 mm Hg after ASA (p0.005). None of the patients had perfusion defects at rest before ASA. After ASA, perfusion defect size, involving the basal septum, decreased from 9.4+/-5.8% early to 5.2+/-4.2% of LV myocardium late after ASA (p0.001). There were no changes in LV size and ejection fraction after ASA. In conclusion, ASA produces small basal ventricular septal infarcts (resting perfusion abnormality) involving10% of the LV myocardium (including ventricular septum). There is a significant reduction in the perfusion abnormality late after ASA without an increase in LV outflow obstruction or recurrence of symptoms.

Osteoporosis is a worldwide problem that is increasing significantly as the global population both increases and ages. While osteoporosis has been extensively studied in recent years, the utilization of traditional Chinese medicine (TCM) for the diagnosis, prevention and treatment of this condition has seldom been examined. This paper examines the theories and the literature that relate to diagnosis, prevention and treatment of bone loss at the time of menopause according to the principles of TCM. It also considers practical developments in these areas as illustrated by the authors' research findings in recent studies. TCM diagnosis attributes a number of different underlying patterns to menopausal bone loss. A very common pattern in this situation is a Kidney qi and yin deficiency pattern. TCM analysis can be used as an early determinant of those persons who are potentially at risk of bone loss. Acupuncture, herbal medicine and Tai Ji exercise can then be applied to prevent and treat osteoporosis. These treatments can be effective, if they are applied correctly. The therapies may also be used in the treatment and prevention of osteoporosis, as well as the general maintenance of women's health during menopause.

This study examined the effects of four-months of treatment using Chinese herbal Shu Di Shan Zha Formula on bone health. Fourteen Australian menopausal women participated in this paired study and completed all the tests at the commencement, 4th month (when the treatment group and control group cross over) and the 8th month (end) of the study. Data from bone structure and function tests (broadband ultrasonic attenuation--BUA and velocity of sound--VOS), biomarkers of bone turnover (osteocalcin--OSTN and urinary pyridum crosslinks--PYR and D-PYR) were collected from each subject. Results showed that Shu Di Shan Zha Formula was able to affect the level of BUA, and reduce the level of D-PYR in menopausal women.

Malignant gliomas are treated by combining surgery and radiation with chemotherapy. Cure is rare and utilizing information arising from our improved understanding of brain tumor biology may be of value. Interferon alpha (IFNalpha) treatment as restorative immunotherapy has been utilized in malignant gliomas in the past. Interferon alpha/beta gene presence is variable in these tumors. The relationship between response to IFNalpha therapy and gene status has not been assessed prospectively. Patients with recurrent malignant gliomas were treated with 8-week courses of IFNalpha. Clinical and laboratory toxicity was assessed and response determined by MRI scans. Tumor interferon alpha/beta gene content was measured. Toxicities included fourteen grade 3/4 neuro-motor events, and eleven grade 3 neuro-cortical events. Rapid tolerance developed and with dose reductions few doses were missed. Three individuals with glioblastoma multiforme demonstrated a partial response. Median time to progression was 24.6 (+/-17.6) weeks for all glioblastomas. The correlation between longer time to progression and lower tumor IFNalpha gene content as measured here was significant. A minority of patients with recurrent malignant gliomas will respond to IFNalpha therapy at starting doses of 20 Mu/m(2) and above. These doses are associated with significant toxicity. A relationship between the tumor IFNalpha gene status and tumor response to therapy may be present. With current improved understanding of IFNalpha toxicities and ability to measure tumor IFNalpha function, this therapy warrants further evaluation for identifying patients whose tumors are likely to be responsive to IFNalpha therapy.

Intracoronary stenting has been shown to improve acute and long-term clinical results compared with coronary angioplasty. However, clinical outcome after medium Palmaz biliary (PB) stent implantation in very large native coronary arteries (4 mm in diameter) is unknown. This study evaluated restenosis and long-term clinical outcome after PB stenting in large native coronary arteries. Between June 1993 and December 1998, 55 patients with 56 lesions were treated with PB stents. Intracoronary stent deployment was successful in all 56 vessels attempted (100%). The mean stenosis was reduced from 65% +/- 10% to 4% +/- 14%. In 48 of the 56 vessels (86%), vessel size was greater than 4.0 mm in diameter and the mean reference vessel diameter was 4.73 +/- 0.7 mm after stenting. Angiographic success was achieved in 100%. Five patients had postprocedural cardiac enzyme elevation. There was no periprocedural death, emergency coronary artery bypass surgery, repeat target lesion revascularization, or acute stent thrombosis. Long-term clinical follow-up at mean of 28 +/- 15 months was obtained in 96% of the patients. Clinical restenosis rate occurred in 18% of ostial (6/34) and 0% of nonostial (0/22) lesions (P0.0001) with an overall clinical restenosis rate of 11%. Repeat angioplasty were performed in these six patients. There were three cardiac and three noncardiac deaths. The overall event-free survival at 1 and 3 years was 92% +/- 4% and 80% +/- 6%, respectively. PB stent implantation in very large native coronary arteries can be performed with a high degree of procedural success and low in-hospital complications. The long-term clinical outcome of patients undergoing PB stenting is associated with excellent event-free survival. However, stenting of ostial lesions remains as an important factor for restenosis even in very large coronary artery stenting.

The attraction of bacteria commonly found in the respiratory tract in cystic fibrosis to glycoprotein at pH 7 has been studied. The effect of washing on the removal of bacteria from the glycoprotein has also been investigated, and the value of doing both washed and unwashed sputum cultures is discussed.