Genomic modelling of the ESR1 Y537S mutation for evaluating function and new therapeutic approaches for metastatic breast cancer.

Drugs that inhibit estrogen receptor-α (ER) activity have been highly successful in treating and reducing breast cancer progression in ER-positive disease. However, resistance to these therapies presents a major clinical problem. Recent genetic studies have shown that mutations in the ER gene are found in >20% of tumours that progress on endocrine therapies. Remarkably, the great majority of these mutations localize to just a few amino acids within or near the critical helix 12 region of the ER hormone binding domain, where they are likely to be single allele mutations. Understanding how these mutations impact on ER function is a prerequisite for identifying methods to treat breast cancer patients featuring such mutations. Towards this end, we used CRISPR-Cas9 genome editing to make a single allele knock-in of the most commonly mutated amino acid residue, tyrosine 537, in the estrogen-responsive MCF7 breast cancer cell line. Genomic analyses using RNA-seq and ER ChIP-seq demonstrated that the Y537S mutation promotes constitutive ER activity globally, resulting in estrogen-independent growth. MCF7-Y537S cells were resistant to the anti-estrogen tamoxifen and fulvestrant. Further, we show that the basal transcription factor TFIIH is constitutively recruited by ER-Y537S, resulting in ligand-independent phosphorylation of Serine 118 (Ser118) by the TFIIH kinase, cyclin-dependent kinase (CDK)7. The CDK7 inhibitor, THZ1 prevented Ser118 phosphorylation and inhibited growth of MCF7-Y537S cells. These studies confirm the functional importance of ER mutations in endocrine resistance, demonstrate the utility of knock-in mutational models for investigating alternative therapeutic approaches and highlight CDK7 inhibition as a potential therapy for endocrine-resistant breast cancer mediated by ER mutations.

Crosstalk-induced loss of miR-126 promotes angiogenesis.

A molecular environment that promotes vascularization around human carcinomas can materialise rapidly, and has been termed the angiogenic switch. Turning this switch toward a proangiogenic state involves an altered interplay between tumor cells and multiple components of the surrounding stroma. The regulatory landscape of these interactions in cervical cancer is now investigated by Huang et al. in this issue of Oncogene, who demonstrate that the microRNA miR-126 is downregulated during cancer progression, particularly in stromal cells. Such a reduction of miR-126 is shown to free at least one target, the proangiogenic adrenomedullin, from repression, enhancing vascular growth especially at the in situ to invasive carcinoma transition. The study implicates the temporal, spatial and progressive nature of tumor-stroma interactions during carcinogenesis, while in turn suggesting therapeutic strategies.

Cervico-oculo-Acoustic syndrome in a male with consanguineous parents.

BACKGROUND: The cervico-oculo-acoustic syndrome comprises Klippel-Feil anomaly, sensorineural deafness and Duane's retraction syndrome. Polygenic, autosomal dominant, and X-linked inheritance have been hypothesized. The disorder has rarely been reported in males. CASE REPORT: A 42-year-old male, born of consanguineous parents, presented with Duane's syndrome, mixed hearing loss, C2-C3 fusion, neck stiffness, and right facial palsy. A variety of cardiac, neurological and urogenital anomalies occurred in his relatives. The electro-oculographic studies showed impaired abduction and adduction of the right eye and impaired abduction of the left eye. Vergence, vertical eye movements and peripheral vestibular responses were normal. Somatosensory evoked potentials showed absence of the N13 peak and brainstem auditory evoked potentials bilateral delay of the I-III interpeak latencies. CONCLUSIONS: Consanguinity of the patient's parents, not previously reported, suggests autosomal recessive inheritance, but autosomal dominant inheritance is indicated by the family history. The pattern of the oculomotor deficit is consistent with bilateral dysplasia of the abducens nuclei with preserved internuclear neurons in the right abducens nucleus. Neurophysiological investigations revealed lower brainstem and cervical cord involvement.

[Association of biliary calculosis and portal cavernomatosis]. / Associazione tra calcolosi biliare e cavernomatosi portale.

This paper reports the case of a woman, who underwent surgery because of cholelithiasis, with intraoperative finding of prehepatic portal hypertension from portal vein thrombosis ("portal cavernoma") with healthy liver, later confirmed by angiographic studies. This rare pathologic association carries a higher risk of major operative complications; therefore the Authors agree with the general belief that, for these cases, biliary tract surgery should be as simple and safe as possible. In the case of preoperative diagnosis of biliary disease associated with portal cavernoma, should a surgical approach on the biliary tract be required, we agree on the advisability of performing a shunting procedure before any kind of biliary surgery. In case of variceal bleeding endoscopic sclerotherapy will be the first choice; surgical procedures (shunting) should be seen as a second choice in case of rebleeding after sclerotherapy.

[Prolapse of the vaginal vault complicated by ileal evisceration. Possible role of dacron mesh in emergencies. Technical notes]. / Prolasso della cupola vaginale complicato da eviscerazione ileale. Possibile ruolo della rete di Dacron in urgenza. Note di tecnica.

The prolapse of vaginal vault after hysterectomy is a rather common event, whereas ileal evisceration and intestinal occlusion following a complete rupture of an inverted vaginal vault is extremely rare. The Authors report a case successfully treated using a modified Feldman and Birnbaum colposacropexy. The technique, which takes into account pathophysiologic mechanisms of vaginal prolapse, is described in detail and involves the use of a Dacron mesh.