LBA3_PRAlpelisib (ALP) + fulvestrant (FUL) for advanced breast cancer (ABC): Results of the phase III SOLAR-1 trial

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Alpelisib for PIK3CA-mutated, hormone receptor–positive advanced breast cancer

© 2019 Massachusetts Medical Society. All rights reserved. This document is the Published version of a Published Work that appeared in final form in New England Journal of Medicine.To access the final edited and published work see https://doi.org/10.1056/NEJMoa1813904Background: PIK3CA mutations occur in approximately 40% of patients with hormone receptor (HR)–positive, human epidermal growth factor receptor 2 (HER2)–negative breast cancer. The PI3Kα-specific inhibitor alpelisib has shown antitumor activity in early studies. Methods: In a randomized, phase 3 trial, we compared alpelisib (at a dose of 300 mg per day) plus fulvestrant (at a dose of 500 mg every 28 days and once on day 15) with placebo plus fulvestrant in patients with HR-positive, HER2-negative advanced breast cancer who had received endocrine therapy previously. Patients were enrolled into two cohorts on the basis of tumor-tissue PIK3CA mutation status. The primary end point was progression-free survival, as assessed by the investigator, in the cohort with PIK3CA-mutated cancer; progression-free survival was also analyzed in the cohort without PIK3CA-mutated cancer. Secondary end points included overall response and safety. Results: A total of 572 patients underwent randomization, including 341 patients with confirmed tumor-tissue PIK3CA mutations. In the cohort of patients with PIK3CA-mutated cancer, progression-free survival at a median follow-up of 20 months was 11.0 months (95% confidence interval [CI], 7.5 to 14.5) in the alpelisib–fulvestrant group, as compared with 5.7 months (95% CI, 3.7 to 7.4) in the placebo–fulvestrant group (hazard ratio for progression or death, 0.65; 95% CI, 0.50 to 0.85; P<0.001); in the cohort without PIK3CA-mutated cancer, the hazard ratio was 0.85 (95% CI, 0.58 to 1.25; posterior probability of hazard ratio <1.00, 79.4%). Overall response among all the patients in the cohort with PIK3CA-mutated cancer was greater with alpelisib–fulvestrant than with placebo–fulvestrant (26.6% vs. 12.8%); among patients with measurable disease in this cohort, the percentages were 35.7% and 16.2%, respectively. In the overall population, the most frequent adverse events of grade 3 or 4 were hyperglycemia (36.6% in the alpelisib–fulvestrant group vs. 0.7% in the placebo–fulvestrant group) and rash (9.9% vs. 0.3%). Diarrhea of grade 3 occurred in 6.7% of patients in the alpelisib–fulvestrant group, as compared with 0.3% of those in the placebo–fulvestrant group; no diarrhea of grade 4 was reported. The percentages of patients who discontinued alpelisib and placebo owing to adverse events were 25.0% and 4.2%, respectively. Conclusions: Treatment with alpelisib–fulvestrant prolonged progression-free survival among patients with PIK3CA-mutated, HR-positive, HER2-negative advanced breast cancer who had received endocrine therapy previously. (Funded by Novartis Pharmaceuticals; SOLAR-1 ClinicalTrials.gov number, NCT02437318.

Nonaminoglycoside compounds induce readthrough of nonsense mutations

Large numbers of genetic disorders are caused by nonsense mutations for which compound-induced readthrough of premature termination codons (PTCs) might be exploited as a potential treatment strategy. We have successfully developed a sensitive and quantitative high-throughput screening (HTS) assay, protein transcription/translation (PTT)–enzyme-linked immunosorbent assay (ELISA), for identifying novel PTC-readthrough compounds using ataxia-telangiectasia (A-T) as a genetic disease model. This HTS PTT-ELISA assay is based on a coupled PTT that uses plasmid templates containing prototypic A-T mutated (ATM) mutations for HTS. The assay is luciferase independent. We screened ∼34,000 compounds and identified 12 low-molecular-mass nonaminoglycosides with potential PTC-readthrough activity. From these, two leading compounds consistently induced functional ATM protein in ATM-deficient cells containing disease-causing nonsense mutations, as demonstrated by direct measurement of ATM protein, restored ATM kinase activity, and colony survival assays for cellular radiosensitivity. The two compounds also demonstrated readthrough activity in mdx mouse myotube cells carrying a nonsense mutation and induced significant amounts of dystrophin protein

Chemical treatment enhances skipping of a mutated exon in the dystrophin gene

Duchenne muscular dystrophy (DMD) is a fatal muscle wasting disease caused by a loss of the dystrophin protein. Control of dystrophin mRNA splicing to convert severe DMD to a milder phenotype is attracting much attention. Here we report a dystrophinopathy patient who has a point mutation in exon 31 of the dystrophin gene. Although the mutation generates a stop codon, a small amount of internally deleted, but functional, dystrophin protein is produced in the patient cells. An analysis of the mRNA reveals that the mutation promotes exon skipping and restores the open reading frame of dystrophin. Presumably, the mutation disrupts an exonic splicing enhancer and creates an exonic splicing silencer. Therefore, we searched for small chemicals that enhance exon skipping, and found that TG003 promotes the skipping of exon 31 in the endogenous dystrophin gene in a dose-dependent manner and increases the production of the dystrophin protein in the patient's cells

Acquired resistance to PI3K/mTOR inhibition is associated with mitochondrial DNA mutation and glycolysis

Acquired resistance (AQR) to drug treatment occurs frequently in cancer patients and remains an impediment to successful therapy. The aim of this study was to gain insight into how AQR arises following the application of PI3K/mTOR inhibitors. H1975 lung cancer cells with EGFR T790M mutations that confer resistance to EGFR inhibitors underwent prolonged treatment with the PI3K/mTOR inhibitor, BEZ235. Monoclonal cells with stable and increased resistance to BEZ235 were obtained after 8 months treatment. These AQR clones showed class-specific resistance to PI3K/mTOR inhibitors, reduced G1 cell cycle arrest and impedance of migration following PI3K/mTOR inhibition, reduced PTEN expression and increased Akt and S6RP phosphorylation. Transcriptome analysis revealed the AQR clones had increased expression of the metabolite transporters SLC16A9 and SLC16A7, suggestive of altered cell metabolism. Subsequent experiments revealed that AQR clones possess features consistent with elevated glycolysis, including increased levels of glucose, lactate, glutamine, glucose dependence, GLUT1 expression, and rates of post-glucose extracellular acidification, and decreased levels of reactive oxygen species and rates of oxygen consumption. Combination treatment of BEZ235 with the glycolysis inhibitor 3-bromopyruvate was synergistic in AQR clones, but only additive in parental cells. DNA sequencing revealed the presence of a mitochondrial DNA (mtDNA) MT-C01 variant in AQR but not parental cells. Depletion of mitochondrial DNA in parental cells induced resistance to BEZ235 and other PI3K/mTOR inhibitors, and was accompanied by increased glycolysis. The results of this study provide the first evidence that a metabolic switch associated with mtDNA mutation can be an underlying mechanism for AQR

Ribociclib as First-Line Therapy for HR-Positive, Advanced Breast Cancer

The inhibition of cyclin-dependent kinases 4 and 6 (CDK4/6) could potentially overcome or delay resistance to endocrine therapy in advanced breast cancer that is positive for hormone receptor (HR) and negative for human epidermal growth factor receptor 2 (HER2). In this randomized, placebo-controlled, phase 3 trial, we evaluated the efficacy and safety of the selective CDK4/6 inhibitor ribociclib combined with letrozole for first-line treatment in 668 postmenopausal women with HR-positive, HER2-negative recurrent or metastatic breast cancer who had not received previous systemic therapy for advanced disease. We randomly assigned the patients to receive either ribociclib (600 mg per day on a 3-weeks-on, 1-week-off schedule) plus letrozole (2.5 mg per day) or placebo plus letrozole. The primary end point was investigator-assessed progression-free survival. Secondary end points included overall survival, overall response rate, and safety. A preplanned interim analysis was performed on January 29, 2016, after 243 patients had disease progression or died. Prespecified criteria for superiority required a hazard ratio of 0.56 or less with P The duration of progression-free survival was significantly longer in the ribociclib group than in the placebo group (hazard ratio, 0.56; 95% CI, 0.43 to 0.72; P=3.29×10-6 for superiority). The median duration of follow-up was 15.3 months. After 18 months, the progression-free survival rate was 63.0% (95% confidence interval [CI], 54.6 to 70.3) in the ribociclib group and 42.2% (95% CI, 34.8 to 49.5) in the placebo group. In patients with measurable disease at baseline, the overall response rate was 52.7% and 37.1%, respectively (P Among patients receiving initial systemic treatment for HR-positive, HER2-negative advanced breast cancer, the duration of progression-free survival was significantly longer among those receiving ribociclib plus letrozole than among those receiving placebo plus letrozole, with a higher rate of myelosuppression in the ribociclib group. (Funded by Novartis Pharmaceuticals; ClinicalTrials.gov number, NCT01958021 .)

Mohja Kahf's E-Mails to Scheherazad: A Riposte to the Parochial Perspectives of Identity

Identity is a sense of self compiled by an individual's constant negotiations with personal, communal, and national histories with continually shifting conjunctions and disjunctions, with socio-politico-cultural acceptances and rejections and invariably with others' perception of their self. It's a Sisyphean task to address identity as it involves an incessant process of deconstructing and re-constructing the signifying variables that answer the question 'Who Am I?'&nbsp;&nbsp;&nbsp; The situation is more complex for the diasporas as their conflict is twofold. They have to contest with both the sides of their hyphenated identity. The Arab-American women writers are progressively and effectively contradicting the dogmatic and chauvinistic mindsets (both within and without the community) that are perpetually stifling their sense of dignity and identity. One such effort is made by Mohja&nbsp;Kahf through her jolting yet emotive poetry which is a counterstroke to all those who are trying to confine her existence in rigid patriarchal and racial enclosures. Kahf's E‑Mails from Scheherazad is a collection of powerful enunciations that shatter the dual stereotypes of race and gender. The paper is an endeavour to analyse how Kahf's poems challenges and pulverizes the rigid gendered bigotries? What are the complexities inherent in constructing an Arab-American identity? And how do Arab Muslim women negotiate their sense of self that is caught in a flux of belonging and non-belonging in a foreign land? The paper seeks to answer these questions by analysing the ways in which Kahf uses elements of storytelling in her poetry and makes her work celebrate the quintessential fabric of Arab womanhood

Association of bilateral, multiple presumed retinal astrocytic proliferations with combined hamartoma of retina and retinal pigment epithelium in a 9-year-old male child with neurofibromatosis type 2

Neurofibromatosis type 2 (NF-2) is characterized by multifocal proliferation of neural crest-derived cells. The characteristics finding of NF-2 is bilateral vestibular schwannomas. Combined hamartoma of retina and retinal epithelium (CHRRPE) is another associated finding. A 9 year-old-male child presented with left eye decreased vision for 3 months. Visual acuity was 0.0 and 0.8 LogMAR in the right and left eye, respectively. Left fundus showed an elevated, pigmented lesion with surface wrinkling and vascular tortuosity suggestive of CHRRPE with multiple presumed retinal astrocytic proliferations in mid-periphery. He had multiple café-au-lait spots. Optical coherence tomography confirmed clinical findings. Magnetic resonance imaging brain showed bilateral acoustic neuroma. Recognition of this rare finding as presenting feature of NF-2 can lead to earlier diagnosis which is vital to appropriate surveillance and possible surgical intervention. It is recommended that children with CHRRPE be screened for NF-2