32 research outputs found
ERK1/2 inhibitors: New weapons to inhibit the RAS-regulated RAF-MEK1/2-ERK1/2 pathway
The RAS-regulated RAF-MEK1/2-ERK1/2 signalling pathway is de-regulated in a variety of cancers due to mutations in receptor tyrosine kinases (RTKs), negative regulators of RAS (such as NF1) and core pathway components themselves (RAS, BRAF, CRAF, MEK1 or MEK2). This has driven the development of a variety of pharmaceutical agents to inhibit RAF-MEK1/2-ERK1/2 signalling in cancer and both RAF and MEK inhibitors are now approved and used in the clinic. There is now much interest in targeting at the level of ERK1/2 for a variety of reasons. First, since the pathway is linear from RAF-to-MEK-to-ERK then ERK1/2 are validated as targets per se. Second, innate resistance to RAF or MEK inhibitors involves relief of negative feedback and pathway re-activation with all signalling going through ERK1/2, validating the use of ERK inhibitors with RAF or MEK inhibitors as an up-front combination. Third, long-term acquired resistance to RAF or MEK inhibitors involves a variety of mechanisms (KRAS or BRAF amplification, MEK mutation, etc.) which re-instate ERK activity, validating the use of ERK inhibitors to forestall acquired resistance to RAF or MEK inhibitors. The first potent highly selective ERK1/2 inhibitors have now been developed and are entering clinical trials. They have one of three discrete mechanisms of action - catalytic, "dual mechanism" or covalent - which could have profound consequences for how cells respond and adapt. In this review we describe the validation of ERK1/2 as anti-cancer drug targets, consider the mechanism of action of new ERK1/2 inhibitors and how this may impact on their efficacy, anticipate factors that will determine how tumour cells respond and adapt to ERK1/2 inhibitors and consider ERK1/2 inhibitor drug combinations
Participatory Action Research on School Culture and Student Mental Health: A Study Protocol
Background: Young people spend a large proportion of their time in school, which presents both risk and protective factors for their mental health. A supportive school culture can promote and protect good mental health by creating experiences of safety and belonging amongst staff and students. In this qualitative study, we seek to explore whether a participatory action research (PAR) approach is an effective way to promote and improve student mental health. Methods: Participatory action research is an approach in which people collaboratively research their own experience: the researched communities become co-researchers of their own experiences in a specific context. We will work with four secondary schools in the UK to develop PAR projects. In each school, a group of 2ā4 staff and 6ā8 students will work together to develop a shared understanding of their school culture and to introduce activities or changes to make the culture more supportive of student mental health. We will evaluate the effectiveness of the PAR approach through i) a review of school documents pertaining to mental health (e.g., policies and Ofsted reports), ii) interviews with staff members ( n = 40), parents ( n = 8) and students ( n = 24ā40) before and after the PAR intervention, iii) observations and reports of the PAR group meetings and iv) interviews with members of the PAR groups after the PAR intervention. Discussion: We anticipate that our research findings will advance knowledge on effective methods to develop a positive school culture that will contribute to the improvement of young peopleās mental health and well-being. We will seek to identify the mechanisms through which school culture can have a positive impact on mental health and develop a logic model and a school culture toolkit that can be utilised as a resource to inform public health interventions to promote mental health in a range of educational settings.National Institute for Health Research (NIHR) School for Public Health Research (Grant Reference Number PDāSPHā2015)
Visualization of Endogenous ERK1/2 in Cells with a Bioorthogonal Covalent Probe
The RASāRAFāMEKāERK pathway has been intensively studied in oncology, with RAS known to be mutated in ā¼30% of all human cancers. The recent emergence of ERK1/2 inhibitors and their ongoing clinical investigation demands a better understanding of ERK1/2 behavior following small-molecule inhibition. Although fluorescent fusion proteins and fluorescent antibodies are well-established methods of visualizing proteins, we show that ERK1/2 can be visualized via a less-invasive approach based on a two-step process using inverse electron demand DielsāAlder cycloaddition. Our previously reported trans-cyclooctene-tagged covalent ERK1/2 inhibitor was used in a series of imaging experiments following a click reaction with a tetrazine-tagged fluorescent dye. Although limitations were encountered with this approach, endogenous ERK1/2 was successfully imaged in cells, and āon-targetā staining was confirmed by over-expressing DUSP5, a nuclear ERK1/2 phosphatase that anchors ERK1/2 in the nucleus
Could a brief assessment of negative emotions and self-esteem identify adolescents at current and future risk of self-harm in the community? A prospective cohort analysis
Background: Self-harm is common in adolescents, but it is often unreported and undetected. Available screening
tools typically ask directly about self-harm and suicidal ideation. Although in an ideal world, direct enquiry and
open discussion around self-harm would be advocated, non-psychiatric professionals in community settings are
often reluctant to ask about this directly and disclosure can be met with feeling of intense anxiety. Training
non-specialist staff to directly ask about self-harm has limited effects suggesting that alternative approaches are
required. This study investigated whether a targeted analysis of negative emotions and self-esteem could identify
young adolescents at risk of self-harm in community settings.
Methods: Data were collected as part of a clinical trial from young people in school years 8ā11 (aged 12ā16) at
eight UK secondary schools (N = 4503 at baseline, N = 3263 in prospective analysis). The Short Mood and Feelings
Questionnaire, Revised Child Anxiety and Depression Scale, Rosenberg Self-Esteem Scale, personal failure (Childrenās
Automatic Thoughts Scale), and two items on self-harm were completed at baseline, 6 and 12 months.
Results: Following a process of Principal Components Analysis, item reduction, and logistic regression analysis,
three internally reliable factors were identified from the original measures that were independently associated with
current and future self-harm; personal failure (3 items), physical symptoms of depression/anxiety (6 items), positive
self-esteem (5 items). The summed score of these 14 items had good accuracy in identifying current self-harm
(AUC 0.87 girls, 0.81 boys) and at six months for girls (0.81), and fair accuracy at six months for boys (AUC 0.74) and
12 months for girls (AUC 0.77).
Conclusions: A brief and targeted assessment of negative emotions and self-esteem, focusing on factors that are
strongly associated with current and future self-harm, could potentially be used to help identify adolescents who
are at risk in community settings. Further research should assess the psychometric properties of the items identified
and test this approach in more diverse community contexts