Search

Recent advances in the treatment of gastric cancer (GC) with chemotherapy, immunotherapy, anti-angiogenic therapy and targeted therapies have yielded some improvement in survival outcomes; however, metastatic GC remains a lethal malignancy and amongst the leading causes of cancer-related mortality worldwide. Importantly, the ongoing molecular characterisation of GCs continues to uncover potentially actionable molecular targets. Among these, aberrant FGFR2-driven signalling, predominantly arising from FGFR2 amplification, occurs in approximately 3-11% of GCs. However, whilst several inhibitors of FGFR have been clinically tested to-date, there are currently no approved FGFR-directed therapies for GC. In this review, we summarise the significance of FGFR2 as an actionable therapeutic target in GC, examine the recent pre-clinical and clinical data supporting the use of small-molecule inhibitors, antibody-based therapies, as well as novel approaches such as proteolysis-targeting chimeras (PROTACs) for targeting FGFR2 in these tumours, and discuss the ongoing challenges and opportunities associated with their clinical development.

Objective: Discourse analysis is one of the clinical methods commonly used to assess the language ability of individuals with traumatic brain injury (TBI). However, the majority of published analytic frameworks are not geared for highlighting the pragmatic aspect of discourse deficits in acquired language disorders, except for those designed for quantifying conversational samples. This study aimed to examine how pragmatic competence is impaired and reflected in spoken monologues in Chinese speakers with TBI., Methods: Discourse samples of five tasks (personal narrative, storytelling, procedural, single- and sequential picture description) were elicited from ten TBI survivors and their controls. Each discourse sample was measured using 16 indices (e.g., number of informative words, percentage of local/global coherence errors, repeated words or phrases) that corresponded to the four Gricean maxims. Twenty-five naïve Chinese speakers were also recruited to perform perceptual rating of the quality of all 50 TBI audio files (five discourse samples per TBI participant), in terms of erroneous/inaccurate information, adequacy of amount of information given, as well as degree of organization and clarity., Results: The maxim of quantity best predicted TBI's pragmatic impairments. Naïve listeners' perception of pragmatics deficits correlated to measures on total and informative words, as well as number and length of terminable units. Clinically, personal narrative and storytelling tasks could better elicit violations in pragmatics., Conclusion: Applying Gricean maxims in monologic oral narratives could capture the hallmark underlying pragmatic problems in TBI. This may help provide an additional approach of clinically assessing social communications in and subsequent management of TBI.

In studying language acquisition in children, sizable research studies have been focusing on the investigation of form and lexical semantics. This study aims to establish a child language database annotated both syntactically with part of speech and semantically with semantic content category to supplement the study of child language acquisition in the semantic domain beyond lexical level. The Corpus of Mandarin Child Language (CMCL) that documented the production of different semantic content categories by Mandarin-speaking children was established. Naturalistic language samples of 82 native Mandarin-speaking children aged 25-60 months, divided into three age groups, were obtained. The corresponding semantic content categories coded in each utterance were tagged according to previous studies, in addition to the annotations of part of speech. MLU and lexical diversity were examined and the usage and acquisition of different semantic content categories were also analyzed. The results regarding syntactic complexity and lexical diversity replicated the typical language acquisition pattern from previous studies, which supported the validity of the data obtained in the CMCL. To investigate the trajectory of acquisition of various semantic content categories by age, a 90% acquisition criterion was used. Our findings regarding the acquisition order of semantic content category were basically in line with previous studies in general, with some minor differences. This acquisition order observed is largely explained by the cognitive and syntactic complexity associated with the semantic content category, with additional influence from language specific properties and cultural specific factors of Mandarin. In addition, with the tags in both part-of-speech and semantic content category, the CMCL potentially provides a platform for examining the form-content interface in early child language acquisition, which also implies significantly on the theoretical and clinical ground., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Tang, Lau and Leung.)

Several norms of psycholinguistic features of Chinese characters exist in Mandarin Chinese, but only a few are available in Cantonese or in the traditional script, and none includes semantic radical transparency ratings. This study presents subjective ratings of age-of-acquisition (AoA), familiarity, imageability, concreteness, and semantic radical transparency in 4376 Chinese characters. The single Chinese characters were rated individually on the five dimensions by 20 native Cantonese speakers in Hong Kong to form the Hong Kong Chinese Character Psycholinguistic Norms (HKCCPN). The split-half reliability and intra-class correlations testified to the high internal reliability of the ratings. Their convergent and discriminant patterns in relations to other psycholinguistic measures echoed previous findings reported on Chinese. There were high correlations for semantic radical transparency, imageability and concreteness, and moderate-to-high correlations for AoA and familiarity among subsets of items that had been collected in previous studies. Concurrent validity analyses showed convergence in predicting behavioral response times in various tasks (lexical decision, naming, and writing-to-dictation) when compared with other Chinese character databases. High predictive validity was shown in writing-to-dictation data from an independent sample of 20 native Cantonese speakers. Several objective psycholinguistic measures (character frequency, stroke number, number of words formed, number of homophones and number of meanings) were included in this database to facilitate its use. These new ratings extend the currently available norms in language and reading research in Cantonese Chinese for researchers, clinicians, and educators, as well as provide them with a wider choice of stimuli., (© 2022. The Author(s).)

It has been well-documented that language input designed according to the principles of statistical learning can promote language acquisition among children with or without language disorder. Cantonese-speaking children with language disorder were reported to have difficulties using expanded verb phrases and prepositional phrases, but the corresponding intervention is relatively unexplored. The current study evaluated the efficacy of an intervention designed using the statistical learning principles to promote the acquisition of these two structures. A retrospective study of existing data collected from a total of 16 Cantonese-speaking children (four female; mean age = 6.70 years) with suspected language disorder was conducted. The participants were initially divided into the 'Treatment' and the 'Control' groups. A total of eight sessions of language treatment, which focused on giving systematic language input of expanded verb phrases and prepositional phrases, were conducted on each child. Results showed that the Treatment group produced significantly more expanded verb phrases in the post-treatment language samples, while the Control group did not. The final pre- and post-comparison conducted after the Control group also received treatment indicated overall significant increased number of expanded verb phrases produced across time. On the contrary, improvement in the production of prepositional phrases was not significant. It is suggested that the unique thematic roles coded by individual prepositions possibly restricted the generalisation effect of treatment, which explains the non-significant improvement across time. Theoretical and clinical implications were discussed.

Background: Dihydropyrimidine dehydrogenase (DPD) is a key enzyme in the metabolism of fluoropyrimidines. Variations in the encoding DPYD gene are associated with severe fluoropyrimidine toxicity and up-front dose reductions are recommended. We conducted a retrospective study to evaluate the impact of implementing DPYD variant testing for patients with gastrointestinal cancers in routine clinical practice in a high volume cancer centre in London, United Kingdom., Methods: Patients receiving fluoropyrimidine chemotherapy for gastrointestinal cancer prior to, and following the implementation of DPYD testing were identified retrospectively. After November 2018, patients were tested for DPYD variants c.1905+1G>A (DPYD*2A), c.2846A>T (DPYD rs67376798), c.1679T>G (DPYD*13), c.1236G>A (DPYD rs56038477), c.1601G>A (DPYD*4) prior to commencing fluoropyrimidines alone or in combination with other cytotoxics and/or radiotherapy. Patients with a DPYD heterozygous variant received an initial dose reduction of 25-50%. Toxicity by CTCAE v4.03 criteria was compared between DPYD heterozygous variant and wild type carriers., Results: Between 1 st December 2018 and 31 st July 2019, 370 patients who were fluoropyrimidine naïve underwent a DPYD genotyping test prior to receiving a capecitabine (n = 236, 63.8%) or 5FU (n = 134, 36.2%) containing chemotherapy regimen. 33 patients (8.8%) were heterozygous DPYD variant carriers and 337 (91.2%) were wild type. The most prevalent variants were c.1601G > A (n = 16) and c.1236G > A (n = 9). Mean relative dose intensity for the first dose was 54.2% (range 37.5-75%) for DPYD heterozygous carriers and 93.2% (42.9-100%) for DPYD wild type carriers. Overall grade 3 or worse toxicity was similar in DPYD variant carriers (4/33, 12.1%) as compared to wild-type carriers (89/337, 25.7%; P = 0.0924)., Conclusions: Our study demonstrates successful routine DPYD mutation testing prior to the initiation of fluoropyrimidine chemotherapy with high uptake. In patients with DPYD heterozygous variants with pre-emptive dose reductions, high incidence of severe toxicity was not observed. Our data supports routine DPYD genotype testing prior to commencement of fluoropyrimidine chemotherapy., (© 2023. The Author(s).)

Introduction: Patients with gastrointestinal (GI) cancers have an increased risk of serious complications and death from SARS-CoV-2 infection. The immunogenicity of vaccines in patients with GI cancers receiving anti-cancer therapies is unclear. We conducted a prospective study to evaluate the prevalence of neutralizing antibodies in a cohort of GI cancer patients receiving chemotherapy following SARS-CoV-2 vaccination., Materials and Methods: Between September 2020 and April 2021, patients with cancer undergoing chemotherapy were enrolled. At baseline (day 0), days 28, 56, and 84, we assessed serum antibodies to SARS-CoV-2 spike (anti-S) and anti-nucleocapsid (anti-NP) and concomitantly assessed virus neutralization using a pseudovirus neutralization assay. Patients received either the Pfizer/BioNTech BNT162b2, or the Oxford/AstraZeneca ChAdOx1 vaccine., Results: All 152 patients enrolled had a prior diagnosis of cancer; colorectal (n = 80, 52.6%), oesophagogastric (n = 38, 25.0%), and hepato pancreatic biliary (n = 22, 12.5%). Nearly all were receiving systemic anti-cancer therapy (99.3%). Of the 51 patients who did not receive a vaccination prior to, or during the study, 5 patients had detectable anti-NP antibodies. Ninety-nine patients received at least one dose of vaccine prior to, or during the study. Within 19 days following the first dose of vaccine, 30.0% had anti-S detected in serum which increased to 70.2% at days 20-39. In the 19 days following a second dose, anti-S positivity was 84.2% (32/38). However, pseudovirus neutralization titers (pVNT80) decreased from days 20 to 39., Conclusion: Despite the immunosuppressive effects of chemotherapy, 2 doses of SARS-CoV-2 vaccines are able to elicit a protective immune response in patients' ongoing treatment for gastrointestinal cancers. Decreases in pseudoviral neutralization were observed after 20-39 days, re-affirming the current recommendation for vaccine booster doses., Clinical Trial Registration Number: NCT04427280., (© The Author(s) 2022. Published by Oxford University Press.)

Despite recent advances in the systemic treatment of gastroesophageal cancers, prognosis remains poor. Comprehensive molecular analyses have characterized the genomic landscape of gastroesophageal cancer that has established therapeutic targets such as human epidermal growth factor receptor 2 (HER2), vascular endothelial growth factor receptor (VEGFR) and programmed death ligand 1 (PD-L1). The aberrant fibroblast growth factor receptor 2 (FGFR2) pathway is attractive for targetable therapy with FGFR inhibition based on preclinical data showing a pivotal role in the progression of gastric cancer (GC). FGFR2 amplification is the most common FGFR2 gene aberration in gastroesophageal cancer, and most associated with diffuse GC, which is often linked to poorer prognostic outcomes. There has been considerable progress with drug development focused on FGFR inhibition. At present, there is no approved FGFR inhibitor for FGFR2 positive gastroesophageal cancer. A selective FGFR2b monoclonal antibody bemarituzumab is currently being investigated in the first phase III randomized trial for patients with first line advanced GC, which may change the treatment paradigm for FGFR2b positive GC. The role of FGFR signalling, specifically FGFR2 , is less established in oesophageal squamous cell cancer (ESCC) with a paucity of evidence for clinical benefit in these patients. Precision medicine is part of the wider approach in gastrointestinal cancers; however, it can be challenging due to heterogeneity and here circulating tumour DNA (ctDNA) for patient selection may have future clinical utility. In our review, we outline the FGFR pathway and focus on the developments and challenges of targeting FGFR2 driven gastroesophageal cancers., Competing Interests: Dr Anderley Gordon discloses no conflicts of interest in this work. Dr Edwina Johnston discloses no conflicts of interest in this work. Dr David K Lau discloses he is the recipient of the Australasian Gastro-Intestinal Trials Group/Merck Clinical Research Fellowship. Dr Naureen Starlings disclosures include the following: Research Funding: AstraZeneca, BMS, Pfizer, NIHR EME, RMCC, RM/ICR BRC Travel & Accommodation: AstraZeneca, BMS, Eli Lilly, Merck, Roche, MSD Oncology (02/2019 GI ASCO flights and accommodation) Honoraria: Eli Lilly, Merck Serono, MSD Oncology, Pierre Fabre, Servier, GSK, Amgen Advisory Board: Pfizer, AstraZeneca, Servier, MSD (Merck) The authors report no other conflicts of interest in this work., (© 2022 Gordon et al.)

Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Previous investigations on sentence production in English-speaking individuals with traumatic brain injury (TBI) have yielded mixed conclusions based on their findings. While some studies found comparable sentence complexity between speakers with TBI and control speakers, others reported more syntactic and lexical errors, reduced sentence complexity, and erroneous word order transpositions in the sentence production of speakers with TBI. These contradictory findings could possibly be due to the use of language measures that were less sensitive to subtle syntactic impairments among speakers with TBI. In this preliminary report, the language samples obtained from 11 Cantonese-speaking participants with mild-moderate TBI in Guangzhou, with a mean age of 37.6 and mean years of education of 10 years, and nine control speakers with a similar age range and education background were analyzed using in-depth linguistic-oriented frameworks adopted from pervious works in Cantonese. The results indicated that the TBI group produced more errors, different varieties of sentence types, and lower syntactic complexity in their sentence production compared with the control group. The findings suggested that the more refined and linguistic-oriented measures used in the present study were more sensitive in identifying the subtle syntactic impairments produced by the participants with TBI.

Background: Mutations and fusions in Fibroblast Growth Factor Receptor 3 (FGFR3) occur in 10-20% of metastatic urothelial carcinomas and confer sensitivity to FGFR inhibitors. However, responses to these agents are often short-lived due to the development of acquired resistance. The objective of this study was to identify mechanisms of resistance to FGFR inhibitors in two previously uncharacterised bladder cancer cell lines harbouring FGFR3 fusions and assess rational combination therapies to enhance sensitivity to these agents., Methods: Acquired resistance to FGFR inhibitors was generated in two FGFR3 fusion harbouring cell lines, SW780 (FGFR3-BAIAP2L1 fusion) and RT4 (FGFR3-TACC3 fusion), by long-term exposure to the FGFR inhibitor BGJ398. Changes in levels of receptor tyrosine kinases were assessed by phospho-RTK arrays and immunoblotting. Changes in cell viability and proliferation were assessed by the Cell-Titre Glo assay and by propidium iodide staining and FACS analysis., Results: Long term treatment of FGFR3-fusion harbouring SW780 and RT4 bladder cancer cell lines with the FGFR inhibitor BGJ398 resulted in the establishment of resistant clones. These clones were cross-resistant to the clinically approved FGFR inhibitor erdafitinib and the covalently binding irreversible FGFR inhibitor TAS-120, but remained sensitive to the MEK inhibitor trametinib, indicating resistance is mediated by alternate activation of MAPK signalling. The FGFR inhibitor-resistant SW780 and RT4 lines displayed increased expression of pERBB3, and strikingly, combination treatment with an FGFR inhibitor and the ATP-competitive pan-ERBB inhibitor AZD8931 overcame this resistance. Notably, rapid induction of pERBB3 and reactivation of pERK also occurred in parental FGFR3 fusion-driven lines within 24 h of FGFR inhibitor treatment, and combination treatment with an FGFR inhibitor and AZD8931 delayed the reactivation of pERBB3 and pERK and synergistically inhibited cell proliferation., Conclusions: We demonstrate that increased expression of pERBB3 is a key mechanism of adaptive resistance to FGFR inhibitors in FGFR3-fusion driven bladder cancers, and that this also occurs rapidly following FGFR inhibitor treatment. Our findings demonstrate that resistance can be overcome by combination treatment with a pan-ERBB inhibitor and suggest that upfront combination treatment with FGFR and pan-ERBB inhibitors warrants further investigation for FGFR3-fusion harbouring bladder cancers., (© 2022. The Author(s).)

Introduction: Anti-angiogenic drugs are an efficacious class of therapy in the treatment of patients with metastatic colorectal cancer (mCRC). Aflibercept, a vascular endothelial growth factor (VEGF) trap which binds the angiogenic factors VEGF-A, VEGF-B, and placental growth factor (PIGF) is approved in combination with FOLFIRI chemotherapy following progression after an oxaliplatin-containing regimen., Areas Covered: This report provides a review of the practice-changing clinical studies which have established the use of anti-angiogenic therapy as second-line therapy in mCRC including aflibercept with FOLFIRI (5FU, leucovorin, irinotecan). This review also evaluates aflibercept with other chemotherapy regimens as well as efficacy and safety data from real-world studies., Expert Opinion: Aflibercept in combination with FOLFIRI chemotherapy is an established safe and efficacious regimen for the treatment of mCRC as second-line chemotherapy. Although several toxicities have been described, the majority are either low grade or manageable by drug cessation and supportive therapies. For optimal outcomes, patient selection and close observation of toxicities is essential.

Despite recent advances in the treatment of metastatic colorectal cancer (mCRC), 5 years survival rates remain low. Chemotherapy remains as the mainstay of treatment with only few available targeted therapies. Human epidermal growth factor receptor 2 (HER2) amplification occurs in approximately 5% of metastatic colorectal cancer and it has been studied as a mechanism of resistance for anti-epidermal growth factor receptor (EGFR) therapy. Furthermore, several studies such as HERACLES-A, MyPathway and the DESTINY-CRC01 trials have shown significant clinical benefit of HER2 blockade in patients with HER2 amplified mCRC. In this review, we provide an overview of the clinicopathological features of HER2 amplification and mutations in mCRC. In addition, we review HER2 as a biomarker of intrinsic and acquired anti-EGFR resistance as well as the preclinical, clinical and translational studies investigating the use of HER2 targeted therapies and future studies., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

In the current study, the orthographic knowledge required for writing Chinese characters was assessed among participants with L1 Vietnamese background who learn Chinese as a foreign language. A total of 42 undergraduates were recruited. They were invited to participate in a delayed Chinese character copying task consisting of 32 characters. Their Chinese character reading abilities were also obtained using a character naming task. All the tests were conducted online during the pandemic in 2021. Results indicated that the participants' accuracy in the copying task was affected by the familiarity of the characters and the number of strokes of the characters. These effects minimized as reading performance increased. In the inter-stroke interval (ISI) analysis, results indicated a significant boundary effect where ISIs between orthographic units were longer than ISIs within orthographic units, showing the participants' tendency to chunk Chinese characters into functional units when they write. Only high achievers in the reading task demonstrated the use of both large and small grain-size units in writing (i.e., radical-boundary ISI > logographeme-boundary ISI > non-boundary ISI), while the low achievers only used small grain-size units in their writing. We suggest that the delayed copying task incorporated with handwriting measures is an effective method to assess orthographic knowledge of L2 Chinese learners., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Lau, Liang and Nguyen.)

This is a short report of an experiment conducted to investigate the effects of phonology-to-orthography (P-O) consistency, lexical frequency, imageability, and the number of strokes on writing-to-dictation in Chinese. Thirty-two undergraduates were tested using a writing-to-dictation task consisting of 60 Chinese characters without homophones (i.e., P-O consistent) and 60 Chinese characters with at least two homophones (i.e., P-O inconsistent), the responses of which were recorded on an Android tablet. Linear mixed-effect modelling was used to investigate the significance of the different effects on three measures-accuracy, response time (RT), and total writing time. The results indicated that imageability was significant in predicting accuracy and RT; P-O consistency was significant in predicting RT and total writing time; the number of strokes was significant in predicting accuracy and total writing time; and the lexical frequency effect was significant in predicting all three measures. In general, the results supported the dual-route account of writing-to-dictation in Chinese and confirmed that both the lexical-semantic and lexical non-semantic pathways are needed to explain writing-to-dictation in Chinese. The significance of the different effects observed in the three measures also indicated the need to include different measures when studying writing-to-dictation to better understand the time course of the writing process.

Patients with cancer are currently prioritized in coronavirus disease 2019 (COVID-19) vaccination programs globally, which includes administration of mRNA vaccines. Cytokine release syndrome (CRS) has not been reported with mRNA vaccines and is an extremely rare immune-related adverse event of immune checkpoint inhibitors. We present a case of CRS that occurred 5 d after vaccination with BTN162b2 (tozinameran)-the Pfizer-BioNTech mRNA COVID-19 vaccine-in a patient with colorectal cancer on long-standing anti-PD-1 monotherapy. The CRS was evidenced by raised inflammatory markers, thrombocytopenia, elevated cytokine levels (IFN-γ/IL-2R/IL-18/IL-16/IL-10) and steroid responsiveness. The close temporal association of vaccination and diagnosis of CRS in this case suggests that CRS was a vaccine-related adverse event; with anti-PD1 blockade as a potential contributor. Overall, further prospective pharmacovigillence data are needed in patients with cancer, but the benefit-risk profile remains strongly in favor of COVID-19 vaccination in this population., (© 2021. The Author(s).)

Introduction: Gastric and esophageal adenocarcinoma is a leading cause of cancer-related death globally. Surgery is the cornerstone modality for cure where feasible. Clinical studies over the past two decades have provided evidence for the use of perioperative chemotherapy and chemoradiotherapy to improve patient outcomes. However, there remains no global consensus in the optimal use of these therapies. Areas covered: In this review, the authors summarize the latest evidence for perioperative multimodality therapy in resectable esophagogastric adenocarcinoma including the use of combination chemotherapy and targeted therapy containing regimens. In addition, the authors discuss some of the clinical and molecular biomarkers, such as PET imaging and microsatellite instability which can inform future practice and further clinical investigation. Expert opinion: A multimodal approach has been proven to improve survival outcomes over surgery alone. Whilst there is no global standard of care for multi-modality therapies in resectable OG cancer, clinical trials are refining the use of chemotherapy and radiotherapy in the neoadjuvant and adjuvant settings. Further investigation is on-going to further optimize therapy and the integration of molecular targeted agents.

The acquisition of an alphabetic orthography transforms speech processing in the human brain. Behavioral evidence shows that phonological awareness as assessed by meta-phonological tasks like phoneme judgment, is enhanced by alphabetic literacy acquisition. The current study investigates the time-course of the neuro-cognitive operations underlying this enhancement as revealed by event-related potentials (ERPs). Chinese readers with and without proficiency in Jyutping , a Romanization system of Cantonese, were recruited for an auditory onset phoneme judgment task; their behavioral responses and the elicited ERPs were examined. Proficient readers of Jyutping achieved higher response accuracy and exhibited more negative-going ERPs in three early ERP time-windows corresponding to the P1, N1, and P2 components. The phonological mismatch negativity component exhibited sensitivity to both onset and rhyme mismatch in the speech stimuli, but it was not modulated by alphabetic literacy skills. The sustained negativity in the P1-N1-P2 time-windows is interpreted as reflecting enhanced phonetic/phonological processing or attentional/awareness modulation associated with alphabetic literacy and phonological awareness skills., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Zhang, Pattamadilok, Lau, Bakhtiar, Yim, Leung and Zhang.)

Amplification or overexpression of the FGFR family of receptor tyrosine kinases occurs in a significant proportion of gastric cancers. Regorafenib is a multikinase inhibitor of angiogenic and oncogenic kinases, including FGFR, which showed activity in the randomized phase II INTEGRATE clinical trial in advanced gastric cancer. There are currently no biomarkers that predict response to this agent, and whether regorafenib is preferentially active in FGFR-driven cancers is unknown. Through screening 25 gastric cancer cell lines, we identified five cell lines that were exquisitely sensitive to regorafenib, four of which harbored amplification or overexpression of FGFR family members. These four cell lines were also sensitive to the FGFR-specific inhibitors, BGJ398, erdafitinib, and TAS-120. Regorafenib inhibited FGFR-driven MAPK signaling in these cell lines, and knockdown studies confirmed their dependence on specific FGFRs for proliferation. In the INTEGRATE trial cohort, amplification or overexpression of FGFRs 1-4 was detected in 8%-19% of cases, however, this was not associated with improved progression-free survival and no objective responses were observed in these cases. Further preclinical analyses revealed FGFR-driven gastric cancer cell lines rapidly reactivate MAPK/ERK signaling in response to FGFR inhibition, which may underlie the limited clinical response to regorafenib. Importantly, combination treatment with an FGFR and MEK inhibitor delayed MAPK/ERK reactivation and synergistically inhibited proliferation of FGFR-driven gastric cancer cell lines. These findings suggest that upfront combinatorial inhibition of FGFR and MEK may represent a more effective treatment strategy for FGFR-driven gastric cancers., (©2021 American Association for Cancer Research.)

Context: The widespread adoption of quality improvement (QI) in public health departments holds the promise of transformational change for the American public health system; however, there is a lack of published literature pertaining to organization-level experiences with introductory QI training programs for health department staff. This practice report aims to share the innovative approach, experience, and results of introducing staff to QI principles at the Boston Public Health Commission (BPHC)., Program: The BPHC is an accredited health department that introduced more than 80% of its 1100 staff members to QI between January 2015 and December 2018. The commission's QI training program benefited from (1) visible support from senior leaders, (2) well-documented QI training plans, (3) innovative QI training curricula, (4) flexible delivery methods, and (5) a responsive monitoring and evaluation system., Methods: To assess the effectiveness of QI training at the BPHC, participant questionnaires from QI training sessions (run between January 2015 and June 2018) and a separate questionnaire on organizational QI culture (administered to the supervisory staff in May 2018) were assessed using the Kirkpatrick model of training evaluation., Evaluation: On the basis of Kirkpatrick's 4 levels of training effectiveness, 91% of participants were satisfied with training content (level 1), 94% of participants found the facilitators effective (level 2), 84% of participants indicated they would apply QI concepts in everyday work (level 3), and 75% of supervisors reported an organization-wide improvement in QI culture (level 4)., Discussion: These results show that the BPHC's QI training program has been resoundingly effective, with positive outcomes across all 4 levels of the Kirkpatrick model. These results reinforce the idea of the BPHC's experience as an exemplar for introductory QI training. Interested health departments should heed the lessons learned from this and other organizational experiences as they attempt to scale up QI competencies among staff members., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2020 Wolters Kluwer Health, Inc. All rights reserved.)

In the current study, the effects of orthographic and phonological processing in Chinese character copying were investigated using a data set extracted from a database containing handwriting data of 856 stimuli; the responses of which were collected from 100 participants. To investigate the effect of character frequency, radical frequency, and phonetic regularity, 151 phonetic compounds were selected from the database because (1) their corresponding phonetic radicals were all free-standing characters, (2) their corresponding phonetic radicals were located at either the right or the bottom positions in the characters, and (3) no more than 10% of the participants made errors when copying these target characters. The results of the linear mixed effect models revealed that after controlling for inter-stroke distance (ISD) and stroke number, the inter-stroke intervals (ISIs) at the radical and logographeme boundaries were significantly longer, indicating significant orthographic processing in the immediate copying task that radicals and logographemes were used as writing units. In addition, shorter ISIs at the logographeme boundary associated with higher radical frequency, and shorter ISIs at the radical boundary associated with higher character frequency and regular characters, were observed. These observations indicated significant orthographic and phonological effects in the immediate copying task. Finally, the significant phonetic regularity effect observed also supported the notion that phonology contributes to Chinese character writing and that the effects of central processing, including character frequency and phonetic regularity, cascade over peripheral processing during Chinese character copying., (Copyright © 2020 Lau.)

Fiber optic sensor technology offers several advantages for harsh-environment applications. However, the development of optical gas sensing layers that are stable under harsh environmental conditions is an ongoing research challenge. In this work, electronically conducting metal oxide lanthanum-doped strontium titanate (LSTO) films embedded with gold nanoparticles are examined as a sensing layer for application in reducing gas flows at high temperature (600-800 °C). A strong localized surface plasmon resonance (LSPR) based response to hydrogen is demonstrated in the visible region of the spectrum, while a Drude free electron-based response is observed in the near-IR. Characteristics of these responses are studied both on planar glass substrates and on silica fibers. Charge transfer between the oxide film and the gold nanoparticles is explored as a possible mechanism governing the Au LSPR response and is considered in terms of the corresponding properties of the conducting metal oxide-based matrix phase. Principal component analysis is applied to the combined plasmonic and free-carrier based response over a range of temperatures and hydrogen concentrations. It is demonstrated that the combined visible and near-IR response of these films provides improved versatility for multiwavelength interrogation, as well as improved discrimination of important process parameters (concentration and temperature) through application of multivariate analysis techniques.

Biliary tract cancers (BTC) comprise a group of rare and heterogeneous poor-prognosis tumours with the incidence of intrahepatic cholangiocarcinoma increasing over recent years. Combination chemotherapy with gemcitabine and cisplatin is the established first-line treatment for advanced BTC with a significant but modest survival advantage over monotherapy. There remains no accepted standard treatment in the second-line setting, although recent results from a randomised study have shown a survival benefit with 5-fluorouracil and oxaliplatin chemotherapy. Historically, clinical trials investigating targeted therapies in unselected BTC have failed to demonstrate significant clinical benefit. More recently, advancement in molecular exploration of BTC has shed light on the complex biological heterogeneity within these tumours and has also identified actionable genomic aberrations, such as fibroblast growth factor receptor 2 (FGFR2) gene fusions, isocitrate dehydrogenase (IDH) and BRAF mutations, which offer promise with the anticipation of increased responses and durable clinical benefit in selected patients. Several targeted drugs have now entered clinical development with some encouraging results being seen. Here we review the current and rapidly evolving therapeutic landscape of advanced BTC, including targeted therapies and immunotherapy. We also discuss how recent efforts and successes in BTC are overcoming the obstacles typically associated with precision medicine in rare cancers. Ultimately, the management of advanced BTC is likely to become molecularly selected in the near future with the hope of finally improving the bleak prognosis of patients with this disease., Competing Interests: Declaration of Competing Interest A. Athauda: none C. Fong: none DK Lau: none M. Javle: Bayer; BeiGene; Incyte; Merck; Merck Serono; Novartis; Pieris Pharmaceuticals; QED Therapeutics; Rafael Pharmaceuticals; Seattle Genetics G. Abou-Alfa: Research: ActaBiologica, Agios, Array, Astra Zeneca, Bayer, Beigene, BMS, Casi, Celgene, Exelixis, Genentech, Halozyme, Incyte, Lilly, Mabvax, Novartis, Polaris Puma, QED, Roche. Consulting: Agios, Astra Zeneca, Bayer, Beigene, Bioline, BMS, Celgene, CytomX, Debio, Eisai, Exelixis, Flatiron, Genoscience, Incyte, Ipsen, Jansen, LAM, Lilly, Loxo, Merck, MINA, Pfizer, QED, Redhill, Sanofi, Silenseed, Sillajen, Sobi, Targovax, Twoxar, Vicus, Yiviva. K. Steward: Full time employee of QED Therapeutics Inc. I. Chau: Advisory Board: Eli-Lilly, Bristol Meyers Squibb, MSD, Bayer, Roche, Merck-Serono, Five Prime Therapeutics, Astra-Zeneca, Oncologie International, Pierre Fabre. Research funding: Eli-Lilly, Janssen-Cilag, Sanofi Oncology, Merck-Serono. Honorarium: Eli-Lilly., (Copyright © 2020 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Introduction : Outcomes in metastatic colorectal cancer are improving, due to the tailoring of therapy enabled by better understanding of clinical behavior according to molecular subtype. Areas covered : A review of the literature and recent conference presentations was undertaken on the topic of systemic treatment of metastatic colorectal cancer. This review summarizes expert discussion of the current evidence for therapies in metastatic colorectal cancer (mCRC) based on molecular subgrouping. Expert opinion : EGFR-targeted and VEGF-targeted antibodies are now routinely incorporated into treatment strategies for mCRC. EGFR-targeted antibodies are restricted to patients with extended RAS wild-type profiles, with evidence that they should be further restricted to patients with left-sided tumors. Clinically distinct treatment pathways based on tumor RAS, BRAF, HER2 and MMR status, are now clinically applicable. Evidence suggests therapy for additional subgroups will soon be defined; the most advanced being for patients with KRAS G12 C mutation and gene TRK fusion defects.

Studies have shown that logographemes and radicals, subcharacter units in Chinese characters, are represented in the orthographic lexicon and are functional processing units in the writing of Chinese characters. Nevertheless, there is no consensus regarding how characters should be segmented into logographemes and radicals. This article reports handwriting data for a list of 209 Chinese characters (95 nonphonetic compounds and 114 phonetic compounds) in a copying task. To validate the constituent logographemes and radicals of the target Chinese characters, comparisons among between-radical interstroke intervals (ISIs), between-logographeme ISIs, and within-logographeme ISIs, as well as their interactions with orthographic factors including character frequency, stroke number, and configuration, were conducted using factorial analyses. The results showed that the ISI comparison method is effective in validating the constituent logographemes and radicals in Chinese characters. On the basis of this list of 209 stimuli, another 1,227 Chinese characters that share the same set of radicals with the stimuli were further identified. Their constituent logographemes were deduced accordingly. Altogether, the over 1,000 Chinese characters with validated constituent logographemes will serve as a powerful reference for future psycholinguistic and neurolinguistic research. Future potential applications are discussed.

Purpose : Coherence can reflect subtle language deficits in individuals with traumatic brain injury (TBI) and cerebrovascular accident (CVA). This study aimed at investigating whether global and local coherence in Cantonese-speaking adults with CVA and TBI differ from non-brain-injured (NBI) speakers. Factors contributing to the coherence ratings and impacts of elicitation tasks on coherence were examined. Method : Two clinical groups with fluent aphasia (7 CVA and 11 TBI) and 18 controls matched in age and education, who were Cantonese speakers living in China participated. Language samples of single and sequential picture description and storytelling were elicited, and subsequently analysed on global and local coherence, content sequence, and informativeness. Result : TBI speakers had impaired global and local coherence, while CVA speakers had poor global coherence. Sequence of main events produced by the three groups correlated significantly with global coherence. Attention and visuospatial skills were also significantly related to global coherence in both clinical groups. Finally, impaired language integrity was associated with problems of local coherence. Conclusion : The results were consistent with previous studies. Linguistic deficits of coherence in discourse in the two clinical groups and possible impacts of elicitation tasks on the cognitive demands and coherence ratings were discussed.

Biliary tract cancers (BTCs) currently have no approved targeted therapies. Although genomic profiling of primary BTCs has identified multiple potential drug targets, accurate models are needed for their evaluation. Genomic profiling of 22 BTC cell lines revealed they harbor similar mutational signatures, recurrently mutated genes, and genomic alterations to primary tumors. Transcriptomic profiling identified two major subtypes, enriched for epithelial and mesenchymal genes, which were also evident in patient-derived organoids and primary tumors. Interrogating these models revealed multiple mechanisms of MAPK signaling activation in BTC, including co-occurrence of low-activity BRAF and MEK mutations with receptor tyrosine kinase overexpression. Finally, BTC cell lines with altered ERBB2 or FGFRs were exquisitely sensitive to specific targeted agents, whereas surprisingly, IDH1-mutant lines did not respond to IDH1 inhibitors in vitro. These findings establish BTC cell lines as robust models of primary disease, reveal specific molecular disease subsets, and highlight specific molecular vulnerabilities in these cancers., (Copyright © 2019 The Author(s). Published by Elsevier Inc. All rights reserved.)

Oncogenic activation of the fibroblast growth factor receptor (FGFR) through mutations and fusions of the FGFR gene occur in a variety of different malignancies such as urothelial carcinoma and cholangiocarcinoma. Inhibition of the kinase domain of the FGFR with targeted oral FGFR inhibitors has been shown in both preclinical and early phase clinical trials to lead to meaningful reductions in tumour size and larger confirmatory randomized trials are underway. Acquired resistance to FGFR inhibition using a variety of mechanisms that includes, activation of alternate signaling pathways and expansion of tumour clones with gatekeeper mutations in the FGFR gene. This review summarizes the acquired resistance mechanisms to FGFR therapy and therapeutic approaches to circumventing resistance., Competing Interests: Weickhardt A Research funding: Bristol Myers Squibb; Novartis, Pfizer Advisory board: Bristol Myers Squibb; Novartis; Pfizer; Merck Honoraria: Merck/MSD David Lau/Laura Jenkins: Nil, (© The Author(s) 2019.)

Bacteria of the genus Shigella , consisting of 4 species and >50 serotypes, cause shigellosis, a foodborne disease of significant morbidity, mortality, and economic loss worldwide. Classical Shigella identification based on selective media and serology is tedious, time-consuming, expensive, and not always accurate. A molecular diagnostic assay does not distinguish Shigella at the species level or from enteroinvasive Escherichia coli (EIEC). We inspected genomic sequences from 221 Shigella isolates and observed low concordance rates between conventional designation and molecular serotyping: 86.4% and 80.5% at the species and serotype levels, respectively. Serotype determinants for 6 additional serotypes were identified. Examination of differentiation gene markers commonly perceived as characteristic hallmarks in Shigella showed high variability among different serotypes. Using this information, we developed ShigaTyper, an automated workflow that utilizes limited computational resources to accurately and rapidly determine 59 Shigella serotypes using Illumina paired-end whole-genome sequencing (WGS) reads. Shigella serotype determinants and species-specific diagnostic markers were first identified through read alignment to an in-house curated reference sequence database. Relying on sequence hits that passed a threshold level of coverage and accuracy, serotype could be unambiguously predicted within 1 min for an average-size WGS sample of ∼500 MB. Validation with WGS data from 380 isolates showed an accuracy rate of 98.2%. This pipeline is the first step toward building a comprehensive WGS-based analysis pipeline of Shigella spp. in a field laboratory setting, where speed is essential and resources need to be more cost-effectively dedicated. IMPORTANCE Shigella causes diarrheal disease with serious public health implications. However, conventional Shigella identification methods are laborious and time-consuming and can be erroneous due to the high similarity between Shigella and enteroinvasive Escherichia coli (EIEC) and cross-reactivity between serotyping antisera. Further, serotype interpretation is complicated for inexperienced users. To develop an easier method with higher accuracy based on whole-genome sequencing (WGS) for Shigella serotyping, we systematically examined genomic information of Shigella isolates from 53 serotypes to define rules for differentiation and serotyping. We created ShigaTyper, an automated pipeline that accurately and rapidly excludes non- Shigella isolates and identifies 59 Shigella serotypes using Illumina paired-end WGS reads. A serotype can be unambiguously predicted at a data processing speed of 538 MB/min with 98.2% accuracy from a regular laptop. Once it is installed, training in bioinformatics analysis and Shigella genetics is not required. This pipeline is particularly useful to general microbiologists in field laboratories., (This is a work of the U.S. Government and is not subject to copyright protection in the United States. Foreign copyrights may apply.)

Semantic feature analysis (SFA) is a treatment approach designed for patients with lexical retrieval difficulty caused by semantic deficits. During training, a structured framework (e.g. requiring the patient to name the category, function, and colour of the target items) is usually provided to facilitate the patient in thinking of the semantic features of the target items. Nevertheless, the use of a structured framework potentially limits the variety of semantic features activated for lexical retrieval. This study investigated the effectiveness of modified SFA training to address this potential limitation. An odd-man-out task was carried out in the modified SFA training with an anomic patient with impaired access to the phonological output lexicon. The task aimed to encourage a detailed comparison of semantic features among items in the same category. It is hypothesized that activations of more distinctive semantic features belonging to the target items will result in greater extent of generalizations in the lexical processing. The patient's abilities in naming semantic features at the beginning and at the end of each treatment session were compared. Besides, accuracy and error patterns in oral and written naming in the initial and post-treatment assessment were also compared. The results showed a significant increase in the number of semantic features retrieved within treatment sessions. Moreover, a significant improvement in oral picture naming was also observed subsequent to the modified SFA training. Finally, the results of the error analyses further supported that the modified SFA was effective in promoting overall lexical processing. The findings indicated that both quantity and distinctiveness of concepts activated in the semantic system are essential to effective lexical retrieval. Theoretical and clinical implications were also discussed.

This study investigated the grapho-motor patterns used in writing Chinese characters. A Chinese patient, CSC, who demonstrated post-brain-injury mirror writing, was recruited. In Experiment 1, non-mirrored writing responses were obtained when CSC was instructed to copy asymmetrical non-verbal symbols and pictures. Resembling the patterns observed in a patient's writing reported in a previous study, it was hypothesized that CSC's mirror writing was a result of untransformed preserved grapho-motor patterns. In Experiments 2 and 3, CSC was further instructed to copy real Chinese characters, pseudo-characters with authentic radicals and logographemes (i.e., stroke clusters that frequently occur in radicals), and Hangul characters with stroke clusters resembling the shapes of authentic logographemes. The results showed that CSC demonstrated mirror writing only when authentic Chinese orthographic units were involved. Non-mirrored writing responses were obtained from stimuli without authentic Chinese orthographic units. In sum, CSC's performance supported the existence of grapho-motor patterns of Chinese orthographic units represented in the brain. Theoretical implications were discussed.

The current study investigated the grain size of writing units used by children in copying Chinese characters using handwriting measures. In Experiment 1, 31 Grade 1 and 31 Grade 5 children studying in mainstream schools in Hong Kong were invited to copy 36 pseudo-characters on an Android tablet. The pseudo-characters were constructed by combining, in their legal positions, radicals that contain two logographemes. The pseudo-characters contain only high frequency radicals in one condition and only low frequency radicals in the other condition. Linear mixed effect modeling was used to analyze the significance of radical frequency, radical free-standing frequency, and logographeme frequency in predicting the inter-stroke intervals after controlling for inter-stroke distance and gestalt boundaries of radicals and logographemes. The results showed that all three frequency measures significantly predicted Grade 5 children's inter-stroke intervals while only logographeme frequency and radical free-standing frequency significantly predicted Grade 1 children's inter-stroke intervals. This indicated that older children demonstrated the use of both small and large grain size units in writing Chinese characters while younger children showed tendency to use small grain size units with the support of some large grain size units that they know in writing Chinese characters. In Experiment 2, a Grade 3 child with writing difficulties was assessed using the same task. Results showed that he demonstrated the use of only small grain size units in writing. Theoretical and clinical implications were discussed.

This study investigated the sublexical route in writing Chinese characters. Using a writing-to-dictation task, we compared neurotypical participants' performance on writing a set of 40 characters with homophones sharing different phonetic radicals and another set of 40 characters with homophones sharing the same phonetic radicals. The first set of stimuli was regarded as both syllable-to-character and syllable-to-radical inconsistent, while the second set of stimuli was considered syllable-to-radical consistent but syllable-to-character inconsistent. The results of the error analysis showed that the control participants demonstrated a greater tendency to make errors with preserved phonetic radicals in the second set of stimuli. Furthermore, we conducted the same task with a Chinese brain-injured patient, WCY, who had mild dyslexia and severe dysgraphia associated with mild impairment to the lexical semantic route as shown by the patient's character writing. The results showed that WCY demonstrated similar error patterns as those of the control participants and a shorter writing time in the second set of stimuli. Altogether, the observations were taken as evidence that supported our claim that a syllable-to-phonetic radical route governs the sublexical route in Chinese character writing.

Background: Advanced biliary tract cancers (BTCs) have a poor prognosis and limited treatment options. This exploratory phase II study aimed to evaluate the activity of the mTOR inhibitor everolimus in advanced BTC and explore prognostic biomarkers., Methods: Patients with advanced BTCs, who had not received chemotherapy for advanced disease, were enroled to receive everolimus (10 mg daily). The primary endpoint was disease control rate (DCR) at 12 weeks. Secondary endpoints included overall response rate, progression-free survival (PFS), overall survival (OS) and adverse events. Activation status of the RAS and phosphatidylinositol 3-kinase (PI3K)/AKT/mTOR pathways was assessed by DNA sequencing and immunohistochemistry on archival tumour tissue., Results: The study enroled 27 patients and the DCR at 12 weeks was 48%. Median PFS was 5.5 months (95% confidence interval (CI): 2.1-10.0 months) and median OS was 9.5 months (95% CI: 5.5-16.6 months). DCR at 12 weeks was significantly worse for gall bladder carcinoma compared to other anatomical sites, and there was a trend towards a worsened PFS and OS. Treatment was well tolerated. KRAS (12%) and PIK3CA mutations (12%) were uncommon. Immunohistochemical staining for PI3K/AKT/mTOR pathways did not significantly correlate with outcome., Conclusion: In unselected patients, everolimus demonstrated clinical activity as first-line monotherapy in advanced BTC.

Advanced biliary tract cancer (BTC) has a poor prognosis and limited treatment options. The PI3K/Akt/mTOR signalling pathway is hyperactivated in a subset of BTCs, and clinical activity of the mTOR inhibitor everolimus has been observed in some patients with BTC. The goal of this study was to identify biomarkers predictive of everolimus response. Twenty BTC cell lines were assessed for everolimus sensitivity with a spectrum of growth inhibitory responses observed. Molecular biomarkers of sensitivity and resistance were identified by interrogation of the activation status of the Ras/MAPK and PI3K/Akt/mTOR pathways. K-Ras mutations and/or amplifications were identified in 45% of cell lines and were associated with resistance to everolimus. Activating mutations in PIK3CA or loss of PTEN was not predictive of everolimus response; however, high basal levels of pAKT were associated with sensitivity, independent of Ras/MAPK pathway activation status. Notably, everolimus inhibited mTOR signalling to a similar extent in sensitive and resistant cell lines, suggesting that relative dependence on the mTOR pathway rather than the magnitude of pathway inhibition determines everolimus response. Consistent with the known limitations of rapalogs, everolimus induced feedback-mediated activation of AKT in BTC cell lines, which could be overcome by cotreatment with an AKT inhibitor or ATP-competitive mTORC1/mTORC2 inhibitors. However, both approaches failed to induce greater apoptosis compared to everolimus, and mTORC1/mTORC2 kinase inhibitors induced compensatory activation of pERK, identifying an inherent limitation of these agents in BTC cell lines. These findings suggest that future trials of everolimus in BTC would benefit from preselecting patients based on their K-Ras and PI3K/mTOR pathway activation status. The study also identifies strategies for enhancing inhibition of the PI3K/mTOR pathway in BTC cell lines., (© 2017 The Authors. Published by FEBS Press and John Wiley & Sons Ltd.)

This is a short report of the investigation of the relationship between awareness of morphosyntactic structures in Chinese compound words and reading abilities on 268 fourth graders studying in three mainstream schools in Shenzhen. All children were assessed using reading and cognitive tasks including rapid automatized naming, phonological, orthographic and morphological awareness. A compound production task using pseudo compound words with different morphosyntactic structures in the first and second levels as stimuli was also conducted. Results of ANOVA indicated that main effect of first level morphosyntactic structures, main effect of second level morphosyntactic structures and interaction effects between the two were significant. Children's awareness of different morphosyntactic structures were affected by frequency of usage of individual morphosyntactic structures in the language. Results of hierarchical regression analyses revealed that the awareness of morphosyntactic structures in Chinese compound words is strongly associated with Chinese reading abilities. Theoretical and clinical implications were discussed.

This study investigated the contributions of different cognitive measures in predicting the three types of Chinese characters: regular phonetic compounds, irregular phonetic compounds and non-phonetic compounds. A total of 246 Grade 3 children (mean age = 8.63 yrs) were tested using a bunch of tasks including phonological processing, orthographic processing, morphological processing, rapid automatised naming and Chinese character naming. Results showed that advanced phonological processing skills contributed largely to regular phonetic compounds naming while other cognitive measures predict the naming of the other two types of characters. The results imply that the skills underlying the learning of regular phonetic compounds are different from that of irregular phonetic compounds and non-phonetic compounds, which are similar. Data from three poor readers whose performances pattern on naming different types of Chinese characters agreed with the pattern predicted by their performances in different cognitive tasks provide further support to the claim. Theoretical and pedagogical implications were discussed.

We studied the efficacy, tolerability and clinical courses of dabrafenib in patients with metastatic melanoma who were ineligible for enrolment into a clinical trial. Between July 2011 and May 2013, patients with unresectable stage III or stage IV, V600-mutated metastatic melanoma who were not eligible for inclusion into clinical trials were offered treatment with dabrafenib through a named patient programme. Routine efficacy and toxicity data were collected throughout treatment and studied retrospectively. The endpoints were progression-free survival (PFS), overall survival and best overall response. Thirty-one patients commenced dabrafenib therapy including six individuals who had progressed on a prior BRAF-inhibitor treatment. The majority of patients had cerebral metastases (n=17) and/or a poor performance status [Eastern Cooperative Oncology Group (ECOG)≥2, n=11]. Median overall survival was 5.6 months (range 0.1-22 months). Median PFS was 3.3 months (range 0.1-21) and was similar despite performance status. One patient had a complete response and eight showed partial responses to treatment. Patients with cerebral metastases (n=17) had a median PFS of 4.6 months. Five patients (16%) had dose-limiting toxicities. Despite several poor prognostic features, dabrafenib is a safe and effective treatment in the community setting, with occasional impressive outcomes.

Pointed-P2, the Drosophila ortholog of human ETS1 and ETS2, is a transcription factor involved in Ras/MAP kinase-regulated gene expression. In addition to a DNA-binding ETS domain, Pointed-P2 contains a PNT (or SAM) domain that serves as a docking module to enhance phosphorylation of an adjacent phosphoacceptor threonine by the ERK2 MAP kinase Rolled. Using NMR chemical shift, ¹⁵N relaxation, and amide hydrogen exchange measurements, we demonstrate that the Pointed-P2 PNT domain contains a dynamic N-terminal helix H0 appended to a core conserved five-helix bundle diagnostic of the SAM domain fold. Neither the secondary structure nor dynamics of the PNT domain is perturbed significantly upon in vitro ERK2 phosphorylation of three threonine residues in a disordered sequence immediately preceding this domain. These data thus confirm that the Drosophila Pointed-P2 PNT domain and phosphoacceptors are highly similar to those of the well-characterized human ETS1 transcription factor. NMR-monitored titrations also revealed that the phosphoacceptors and helix H0, as well as region of the core helical bundle identified previously by mutational analyses as a kinase docking site, are selectively perturbed upon ERK2 binding by Pointed-P2. Based on a homology model derived from the ETS1 PNT domain, helix H0 is predicted to partially occlude the docking interface. Therefore, this dynamic helix must be displaced to allow both docking of the kinase, as well as binding of Mae, a Drosophila protein that negatively regulates Pointed-P2 by competing with the kinase for its docking site., (Copyright © 2012 The Protein Society.)

DAXX is a scaffold protein with diverse roles that often depend upon binding SUMO via its N- and/or C-terminal SUMO-interacting motifs (SIM-N and SIM-C). Using NMR spectroscopy, we characterized the in vitro binding properties of peptide models of SIM-N and SIM-C to SUMO-1 and SUMO-2. In each case, binding was mediated by hydrophobic and electrostatic interactions and weakened with increasing ionic strength. Neither isolated SIM showed any significant paralog specificity, and the measured μM range K(D) values of SIM-N toward both SUMO-1 and SUMO-2 were ∼4-fold lower than those of SIM-C. Furthermore, SIM-N bound SUMO-1 predominantly in a parallel orientation, whereas SIM-C interconverted between parallel and antiparallel binding modes on an ms to μs time scale. The differences in affinities and binding modes are attributed to the differences in charged residues that flank the otherwise identical hydrophobic core sequences of the two SIMs. In addition, within its native context, SIM-N bound intramolecularly to the adjacent N-terminal helical bundle domain of DAXX, thus reducing its apparent affinity for SUMO. This behavior suggests a possible autoregulatory mechanism for DAXX. The interaction of a C-terminal fragment of DAXX with an N-terminal fragment of the sumoylated Ets1 transcription factor was mediated by SIM-C. Importantly, this interaction did not involve any direct contacts between DAXX and Ets1, but rather was derived from the non-covalent binding of SIM-C to SUMO-1, which in turn was covalently linked to the unstructured N-terminal segment of Ets1. These results provide insights into the binding mechanisms and hence biological roles of the DAXX SUMO-interacting motifs.

Shiga toxin-producing Escherichia coli (STEC) is a significant foodborne pathogen with great economic consequences. There has been an increased food safety concern with this organism since outbreaks of human illnesses caused by this pathogen were first reported in 1982. Therefore, developing a reliable, sensitive, and rapid assay capable of detecting E. coli O157 and the main toxins produced by STEC (i.e., Shiga toxins 1 [Stx(1)] and 2 [Stx(2)]) will directly benefit regulatory agencies by minimizing analysis time. Here, we use Luminex technology to detect multiple analytes in a single 50-ml sample. Using commercially available monoclonal antibodies coupled to carboxylated magnetic microbeads, we developed an immunoassay capable of simultaneously serotyping E. coli O157 and detecting Stx(1) and/or Stx(2). The specificity and sensitivity of this immunoassay was tested against a collection of 34 E. coli isolates belonging to various O serogroups phenotypically different for Stx. The results were compared with microplate sandwich enzyme-linked immunosorbent assay (ELISA), and no cross-reactivity was observed for any of the monoclonal antibodies used. An increased sensitivity up to 1,000 times was observed in the microbead-based immunoassay when compared with the microplate sandwich ELISA. The results indicate that Luminex technology has the potential to simultaneously detect multiple targets without loss of specificity and/or sensitivity. A blind experiment was conducted with 48 samples of ground beef, lettuce, and milk spiked with ≤2 CFU/g E. coli. All the samples were correctly identified, with no false positives or false negatives. This microbead-based immunoassay could be extended to simultaneously detect additional foodborne pathogens and their toxic markers.

DAXX is a scaffold protein with diverse roles including transcription and cell cycle regulation. Using NMR spectroscopy, we demonstrate that the C-terminal half of DAXX is intrinsically disordered, whereas a folded domain is present near its N terminus. This domain forms a left-handed four-helix bundle (H1, H2, H4, H5). However, due to a crossover helix (H3), this topology differs from that of the Sin3 PAH domain, which to date has been used as a model for DAXX. The N-terminal residues of the tumor suppressor Rassf1C fold into an amphipathic α helix upon binding this DAXX domain via a shallow cleft along the flexible helices H2 and H5 (K(D) ∼60 μM). Based on a proposed DAXX recognition motif as hydrophobic residues preceded by negatively charged groups, we found that peptide models of p53 and Mdm2 also bound the helical bundle. These data provide a structural foundation for understanding the diverse functions of DAXX., (Copyright © 2010 Elsevier Ltd. All rights reserved.)

Ras/MAPK signaling is often aberrantly activated in human cancers. The downstream effectors are transcription factors, including those encoded by the ETS gene family. Using cell-based assays and biophysical measurements, we have determined the mechanism by which Ras/MAPK signaling affects the function of Ets1 via phosphorylation of Thr38 and Ser41. These ERK2 phosphoacceptors lie within the unstructured N-terminal region of Ets1, immediately adjacent to the PNT domain. NMR spectroscopic analyses demonstrated that the PNT domain is a four-helix bundle (H2-H5), resembling the SAM domain, appended with two additional helices (H0-H1). Phosphorylation shifted a conformational equilibrium, displacing the dynamic helix H0 from the core bundle. The affinity of Ets1 for the TAZ1 (or CH1) domain of the coactivator CBP was enhanced 34-fold by phosphorylation, and this binding was sensitive to ionic strength. NMR-monitored titration experiments mapped the interaction surfaces of the TAZ1 domain and Ets1, the latter encompassing both the phosphoacceptors and PNT domain. Charge complementarity of these surfaces indicate that electrostatic forces act in concert with a conformational equilibrium to mediate phosphorylation effects. We conclude that the dynamic helical elements of Ets1, appended to a conserved structural core, constitute a phospho-switch that directs Ras/MAPK signaling to downstream changes in gene expression. This detailed structural and mechanistic information will guide strategies for targeting ETS proteins in human disease.