Selected medical interventions in women with a deleterious BRCA mutation: a population-based study in British Columbia.

Background: We examined the uptake of risk-reducing interventions, including bilateral mastectomy, risk-reducing salpingo-oophorectomy, oral contraceptive pills, tamoxifen, and raloxifene, for the entire population of women with a deleterious BRCA1 or BRCA2 mutation in the Canadian province of British Columbia. Methods: This retrospective population-based study used data available in British Columbia for all women who, between 1996 and 2014, were tested and found to have a BRCA mutation. Rates of risk-reducing interventions stratified according to the type of BRCA mutation and prior history of breast or gynecologic cancer (ovary, fallopian tube, peritoneal) are presented. Cancers diagnosed in women with a BRCA mutation after disclosure of their mutation status are also presented. Results: The final study cohort consisted of 885 patients with a deleterious BRCA1 (n = 474) or BRCA2 (n = 411) mutation. Of the women with no prior breast cancer, 30.8% carrying a BRCA1 mutation and 28.3% carrying a BRCA2 mutation underwent bilateral mastectomy. Of women with no prior gynecologic cancer, 64.7% carrying a BRCA1 mutation and 62.2% carrying a BRCA2 mutation underwent risk-reducing bilateral salpingo-oophorectomy. Rates of chemoprevention with oral contraceptive pills and tamoxifen or raloxifene were low in all groups. In this cohort, 23 gynecologic and 70 breast cancers were diagnosed after disclosure of BRCA mutation status. Conclusions: Our results suggest reasonable uptake of risk-reducing interventions in high-risk women. To minimize the occurrence of breast and ovarian cancer in women with a BRCA1 or BRCA2 mutation, more attention could be paid to ensuring that affected women receive proper counselling and follow-up.

Response to angiotensin blockade with irbesartan in a patient with metastatic colorectal cancer.

BACKGROUND: A patient suffering from metastatic colorectal cancer, treatment-related toxicity and resistance to standard chemotherapy and radiation was assessed as part of a personalized oncogenomics initiative to derive potential alternative therapeutic strategies. PATIENTS AND METHODS: Whole-genome and transcriptome sequencing was used to interrogate a metastatic tumor refractory to standard treatments of a patient with mismatch repair-deficient metastatic colorectal cancer. RESULTS: Integrative genomic analysis indicated overexpression of the AP-1 transcriptional complex suggesting experimental therapeutic rationales, including blockade of the renin-angiotensin system. This led to the repurposing of the angiotensin II receptor antagonist, irbesartan, as an anticancer therapy, resulting in the patient experiencing a dramatic and durable response. CONCLUSIONS: This case highlights the utility of comprehensive integrative genomic profiling and bioinformatics analysis to provide hypothetical rationales for personalized treatment options.

Gastric adenocarcinoma and proximal polyposis of the stomach (GAPPS): a new autosomal dominant syndrome.

OBJECTIVE: The purpose of this study was the clinical and pathological characterisation of a new autosomal dominant gastric polyposis syndrome, gastric adenocarcinoma and proximal polyposis of the stomach (GAPPS). METHODS: Case series were examined, documenting GAPPS in three families from Australia, the USA and Canada. The affected families were identified through referral to centralised clinical genetics centres. RESULTS: The report identifies the clinical and pathological features of this syndrome, including the predominant dysplastic fundic gland polyp histology, the exclusive involvement of the gastric body and fundus, the apparent inverse association with current Helicobacter pylori infection and the autosomal dominant mode of inheritance. CONCLUSIONS: GAPPS is a unique gastric polyposis syndrome with a significant risk of gastric adenocarcinoma. It is characterised by the autosomal dominant transmission of fundic gland polyposis, including areas of dysplasia or intestinal-type gastric adenocarcinoma, restricted to the proximal stomach, and with no evidence of colorectal or duodenal polyposis or other heritable gastrointestinal cancer syndromes.

Germline mutations in CDH1 are infrequent in women with early-onset or familial lobular breast cancers.

BACKGROUND: Germline mutations in CDH1 are associated with hereditary diffuse gastric cancer; lobular breast cancer also occurs excessively in families with such condition. METHOD: To determine if CDH1 is a susceptibility gene for lobular breast cancer in women without a family history of diffuse gastric cancer, germline DNA was analysed for the presence of CDH1 mutations in 318 women with lobular breast cancer who were diagnosed before the age of 45 years or had a family history of breast cancer and were not known, or known not, to be carriers of germline mutations in BRCA1 or BRCA2. Cases were ascertained through breast cancer registries and high-risk cancer genetic clinics (Breast Cancer Family Registry, the kConFab and a consortium of breast cancer genetics clinics in the United States and Spain). Additionally, Multiplex Ligation-dependent Probe Amplification was performed for 134 cases to detect large deletions. RESULTS: No truncating mutations and no large deletions were detected. Six non-synonymous variants were found in seven families. Four (4/318 or 1.3%) are considered to be potentially pathogenic through in vitro and in silico analysis. CONCLUSION: Potentially pathogenic germline CDH1 mutations in women with early-onset or familial lobular breast cancer are at most infrequent.

Multiple granular cell tumors are an associated feature of LEOPARD syndrome caused by mutation in PTPN11.

We report a patient with a clinical and molecular diagnosis of LEOPARD syndrome (LS) associated with multiple granular cell tumors (MGCT). Bidirectional sequencing of exons 7, 12, and 13 of the PTPN11 gene revealed the T468M missense mutation in exon 12. This mutation has been previously reported in patients with LS. To our knowledge, this is the first report of MGCT associated with molecularly characterized LS and provides the first molecular evidence linking granular cell tumors (GCT) to the Ras/mitogen-activated protein (MAP) kinase pathway. We propose that MGCT can be associated with LS. Analysis of GCT from this case tested negatively for loss of heterozygosity (LOH) at the PTPN11 and NF1 loci and did not show deletions of the PTEN gene. The absence of LOH of PTPN11 supports published functional data that T468M is a dominant-negative mutation.

Stress and immunity after traumatic injury: the mind-body link.

Traumatic injury poses a significant psychologic and physiologic threat, challenging a victim's perceptions of control over their environment and life outcomes. The multiple stressors presented by traumatic injury diminishes the patient's perceptions of control, resulting in a subjective stress response. Increased stress response after traumatic injury has been associated with altered immune function and decreased immunity. This paper reviews the current literature on stress and immunity after traumatic injury, focusing on the immune changes induced by excessive serum cortisol. It then presents evidence suggesting that the trauma patient's subjective stress response and diminished perceptions of control may act as factors in the immune changes occurring after injury. Recent studies supporting this hypothesis are reviewed, and recommendations for interventions, nursing practice, and research are discussed.

Penetrating chest trauma.

This article reviews the current concepts in penetrating chest trauma. The authors discuss mechanisms of injury, nursing assessment, and interventions for penetrating injuries resulting in cardiac rupture, cardiac tamponade, tension pneumothorax, hemothorax, great vessel injury, and sucking chest wounds.

Genes encoding components of the olfactory signal transduction cascade contain a DNA binding site that may direct neuronal expression.

Genes which mediate odorant signal transduction are expressed at high levels in neurons of the olfactory epithelium. The molecular mechanism governing the restricted expression of these genes likely involves tissue-specific DNA binding proteins which coordinately activate transcription through sequence-specific interactions with olfactory promoter regions. We have identified binding sites for the olfactory neuron-specific transcription factor, Olf-1, in the sequences surrounding the transcriptional initiation site of five olfactory neuron-specific genes. The Olf-1 binding sites described define the consensus sequence YTCCCYRGGGAR. In addition, we have identified a second binding site, the U site, in the olfactory cyclic nucleotide gated channel and type III cyclase promoters, which binds factors present in all tissue examined. These experiments support a model in which expression of Olf-1 in the sensory neurons coordinately activates a set of olfactory neuron-specific genes. Furthermore, expression of a subset of these genes may be modulated by additional binding factors.

Hormonal stimulation of adenylyl cyclase through Gi-protein beta gamma subunits.

Agonist-bound receptors activate heterotrimeric (alpha beta gamma) G proteins by catalysing replacement by GTP of GDP bound to the alpha subunit, resulting in dissociation of alpha-GTP from the beta gamma subunits. In most cases, alpha-GTP carries the signal to effectors, as in hormonal stimulation and inhibition of adenylyl cyclase by alpha s and alpha i respectively. By contrast, genetic evidence in yeast and studies in mammalian cells suggest that beta gamma subunits of G proteins may also regulate effector pathways. Indeed, of the four recombinant mammalian adenylyl cyclases available for study, two, adenylyl cyclases II and IV, are stimulated by beta gamma. This effect of beta gamma requires costimulation by alpha s-GTP. This conditional pattern of effector responsiveness led to the prediction that receptors coupled to many G proteins will mediate elevation of cellular cyclic AMP, provided that Gs is also active. We now confirm this prediction. Coexpression of mutationally active alpha s with adenylyl cyclase II converted agonists that act through 'inhibitory' receptors (coupled to Gi) into stimulators of cAMP synthesis. Experiments using pertussis toxin and a putative scavenger of beta gamma, the alpha subunit of transducin, suggest that beta gamma subunits of the Gi proteins mediated this stimulation. These findings assign a new signalling function to beta gamma subunits of Gi proteins, the conditional stimulation of cAMP synthesis by adenylyl cyclase II.

Molecular cloning and characterization of a Ca2+/calmodulin-insensitive adenylyl cyclase from rat brain.

Biochemical, immunological, and molecular cloning studies have suggested the existence of multiple forms of adenylyl cyclase (EC 4.6.1.1). An adenylyl cyclase cDNA clone (type II) was isolated from a rat brain library and found to encode a protein of 1090 amino acids that was homologous to but distinct from the previously described Ca2+/calmodulin-stimulated adenylyl cyclase from bovine brain. Expression of the type II cDNA in an insect cell line resulted in an increased level of adenylyl cyclase activity that was insensitive to Ca2+/calmodulin. Addition of activated Gs alpha protein to type II-containing membranes increased enzyme activity. The mRNA encoding the type II protein was expressed at high levels in brain tissue and at low levels in olfactory epithelium and lung. The existence of multiple adenylyl cyclase enzymes may provide for complex and distinct modes of biochemical regulation of cAMP levels in the brain.

Primary structure and functional expression of a cyclic nucleotide-activated channel from olfactory neurons.

Odorant signal transduction occurs in the specialized cilia of the olfactory sensory neurons. Considerable biochemical evidence now indicates that this process could be mediated by a G protein-coupled cascade using cyclic AMP as an intracellular second messenger. A stimulatory G protein alpha subunit is expressed at high levels in olfactory neurons and is specifically enriched in the cilia, as is a novel form of adenylyl cyclase. This implies that the olfactory transduction cascade might involve unique molecular components. Electrophysiological studies have identified a cyclic nucleotide-activated ion channel in olfactory cilia. These observations provide evidence for a model in which odorants increase intracellular cAMP concentration, which in turn activates this channel and depolarizes the sensory neuron. An analogous cascade regulating a cGMP-gated channel mediates visual transduction in photoreceptor cells. The formal similarities between olfactory and visual transduction suggest that the two systems might use homologous channels. Here we report the molecular cloning, functional expression and characterization of a channel that is likely to mediate olfactory transduction.