Expanding the Mutation Spectrum Affecting αIIbβ3 Integrin in Glanzmann Thrombasthenia: Screening of the ITGA2B and ITGB3 Genes in a Large International Cohort.

We report the largest international study on Glanzmann thrombasthenia (GT), an inherited bleeding disorder where defects of the ITGA2B and ITGB3 genes cause quantitative or qualitative defects of the αIIbβ3 integrin, a key mediator of platelet aggregation. Sequencing of the coding regions and splice sites of both genes in members of 76 affected families identified 78 genetic variants (55 novel) suspected to cause GT. Four large deletions or duplications were found by quantitative real-time PCR. Families with mutations in either gene were indistinguishable in terms of bleeding severity that varied even among siblings. Families were grouped into type I and the rarer type II or variant forms with residual αIIbβ3 expression. Variant forms helped identify genes encoding proteins mediating integrin activation. Splicing defects and stop codons were common for both ITGA2B and ITGB3 and essentially led to a reduced or absent αIIbβ3 expression; included was a heterozygous c.1440-13_c.1440-1del in intron 14 of ITGA2B causing exon skipping in seven unrelated families. Molecular modeling revealed how many missense mutations induced subtle changes in αIIb and β3 domain structure across both subunits, thereby interfering with integrin maturation and/or function. Our study extends knowledge of GT and the pathophysiology of an integrin.

Characterization of human pancreatic orthotopic tumor xenografts suitable for drug screening

Background Efforts to identify novel therapeutic options for human pancreatic ductal adenocarcinoma (PDAC) have failed to result in a clear improvement in patient survival to date. Pancreatic cancer requires efficient therapies that must be designed and assayed in preclinical models with improved predictor ability. Among the available preclinical models, the orthotopic approach fits with this expectation, but its use is still occasional. Methods An in vivo platform of 11 orthotopic tumor xenografts has been generated by direct implantation of fresh surgical material. In addition, a frozen tumorgraft bank has been created, ensuring future model recovery and tumor tissue availability. Results Tissue microarray studies allow showing a high degree of original histology preservation and maintenance of protein expression patterns through passages. The models display stable growth kinetics and characteristic metastatic behavior. Moreover, the molecular diversity may facilitate the identification of tumor subtypes and comparison of drug responses that complement or confirm information obtained with other preclinical models. Conclusions This panel represents a useful preclinical tool for testing new agents and treatment protocols and for further exploration of the biological basis of drug responses.

Characterization of human pancreatic orthotopic tumor xenografts suitable for drug screening

Background Efforts to identify novel therapeutic options for human pancreatic ductal adenocarcinoma (PDAC) have failed to result in a clear improvement in patient survival to date. Pancreatic cancer requires efficient therapies that must be designed and assayed in preclinical models with improved predictor ability. Among the available preclinical models, the orthotopic approach fits with this expectation, but its use is still occasional. Methods An in vivo platform of 11 orthotopic tumor xenografts has been generated by direct implantation of fresh surgical material. In addition, a frozen tumorgraft bank has been created, ensuring future model recovery and tumor tissue availability. Results Tissue microarray studies allow showing a high degree of original histology preservation and maintenance of protein expression patterns through passages. The models display stable growth kinetics and characteristic metastatic behavior. Moreover, the molecular diversity may facilitate the identification of tumor subtypes and comparison of drug responses that complement or confirm information obtained with other preclinical models. Conclusions This panel represents a useful preclinical tool for testing new agents and treatment protocols and for further exploration of the biological basis of drug responses.

Diphenyl urea derivatives as inhibitors of transketolase: a structure-based virtual screening.

Transketolase is an enzyme involved in a critical step of the non-oxidative branch of the pentose phosphate pathway whose inhibition could lead to new anticancer drugs. Here, we report new human transketolase inhibitors, based on the phenyl urea scaffold, found by applying structure-based virtual screening. These inhibitors are designed to cover a hot spot in the dimerization interface of the homodimer of the enzyme, providing for the first time compounds with a suggested novel binding mode not based on mimicking the thiamine pyrophosphate cofactor.

Abolishing mammography screening programs?

Biller-Andorno and Jüni (2014), in a widely debated commentary published in the May 22 issue of the New England Journal of Medicine, accept the concept that mammography every 2 years from age 50 can decrease breast cancer mortality by 20%, that is, from five to four deaths per 1000 women over a 10-year period. Both the absolute and the relative risk of breast cancer death may vary depending on the baseline mortality rates in various populations and on the impact of screening mammography in reducing breast cancer mortality, which may well vary around the 20% estimate adopted. We accept, therefore, that there are still uncertainties in the absolute and relative impact of mammography screening on breast cancer mortality, given the different study schemes and mammography intervals, the differences in populations, and the continuous improvements in technology (Warner, 2011; Independent UK Panel on Breast Cancer Screening, 2012). We also agree on the observation that mammography has an appreciable impact on breast cancer mortality (Bosetti et al., 2012), but clearly a much smaller one on total mortality.

Dépistage du cancer ovarien dans la population générale [Ovarian cancer screening in the general population].

Although the incidence of ovarian cancer is low, mortality from this cancer is high due to discovery at a late stage in the majority of cases. So it seems worthwhile to detect ovarian cancer at an early stage. The clinical presentation is nonspecific, thus screening tools have been evaluated. The most efficient screening technique includes two steps: evaluation of CA-125 and then sonography in case of abnormal results of CA-125. Two main studies have been performed in large populations. The PLCO-study has led to negative results: no reduction in ovarian cancer mortality in the screening group with an important increase in surgical morbidity. The final results of the UKCTOCS-study will be known in two years. Currently these data can't allow the realization of ovarian cancer screening in the general population, mainly due to their natural history.

RNA interference screening identifies a novel role for PCTK1/CDK16 in medulloblastoma with c-Myc amplification.

Medulloblastoma (MB) is the most common malignant brain tumor in children and is associated with a poor outcome. cMYC amplification characterizes a subgroup of MB with very poor prognosis. However, there exist so far no targeted therapies for the subgroup of MB with cMYC amplification. Here we used kinome-wide RNA interference screening to identify novel kinases that may be targeted to inhibit the proliferation of c-Myc-overexpressing MB. The RNAi screen identified a set of 5 genes that could be targeted to selectively impair the proliferation of c-Myc-overexpressing MB cell lines: AKAP12 (A-kinase anchor protein), CSNK1α1 (casein kinase 1, alpha 1), EPHA7 (EPH receptor A7) and PCTK1 (PCTAIRE protein kinase 1). When using RNAi and a pharmacological inhibitor selective for PCTK1, we could show that this kinase plays a crucial role in the proliferation of MB cell lines and the activation of the mammalian target of rapamycin (mTOR) pathway. In addition, pharmacological PCTK1 inhibition reduced the expression levels of c-Myc. Finally, targeting PCTK1 selectively impaired the tumor growth of c-Myc-overexpressing MB cells in vivo. Together our data uncover a novel and crucial role for PCTK1 in the proliferation and survival of MB characterized by cMYC amplification.

3B.01: Performance of targeted screening for the identification of hypertension in children

OBJECTIVE: As universal screening of hypertension performs poorly in childhood, targeted screening to children at higher risk of hypertension has been proposed. Our goal was to assess the performance of combined parental history of hypertension and overweight/obesity to identify children with hypertension. We estimated the sensitivity, specificity, negative and positive predictive values of overweight/obesity and parental history of hypertension for the identification of hypertension in children. DESIGN AND METHOD: We analyzed data from a school-based cross-sectional study including 5207 children aged 10 to 14 years from all public 6th grade classes in the canton of Vaud, Switzerland. Blood pressure was measured with a clinically validated oscillometric automated device over up to three visits separated by one week. Children had hypertension if they had sustained elevated blood pressure over the three visits. Parents were interviewed about their history of hypertension. RESULTS: The prevalence of hypertension was 2.2%. 14% of children were overweight or obese and 20% had a positive history of hypertension in either or both parents. 30% of children had either or both conditions. After accounting for several potential confounding factors, parental history of hypertension (odds ratio (OR): 2.6; 95% confidence interval (CI): 1.8-4.0), overweight excluding obesity (OR: 2.5; 95% CI: 1.5-4.2) and obesity (OR: 10.1; 95% CI: 6.0-17.0) were associated with hypertension in children. Considered in isolation, the sensitivity and positive predictive values of parental history of hypertension (respectively 41% and 5%) or overweight/obesity (respectively 43% and 7%) were relatively low. Nevertheless, considered together, the sensitivity of targeted screening in children with either overweight/obesity or paternal history of hypertension was higher (65%) but the positive predictive value remained low (5%). The negative predictive value was systematically high. CONCLUSIONS: Restricting screening of hypertension to children with either overweight/obesity or with hypertensive parents would substantially limit the proportion of children to screen (30%) and allow the identification of a relatively large proportion (65%) of hypertensive cases. That could be a valuable alternative to universal screening.

Screening for ALK in non-small cell lung carcinomas: 5A4 and D5F3 antibodies perform equally well, but combined use with FISH is recommended.

OBJECTIVES: Immunohistochemistry (IHC) has become a promising method for pre-screening ALK-rearrangements in non-small cell lung carcinomas (NSCLC). Various ALK antibodies, detection systems and automated immunostainers are available. We therefore aimed to compare the performance of the monoclonal 5A4 (Novocastra, Leica) and D5F3 (Cell Signaling, Ventana) antibodies using two different immunostainers. Additionally we analyzed the accuracy of prospective ALK IHC-testing in routine diagnostics. MATERIALS AND METHODS: Seventy-two NSCLC with available ALK FISH results and enriched for FISH-positive carcinomas were retrospectively analyzed. IHC was performed on BenchMarkXT (Ventana) using 5A4 and D5F3, respectively, and additionally with 5A4 on Bond-MAX (Leica). Data from our routine diagnostics on prospective ALK-testing with parallel IHC, using 5A4, and FISH were available from 303 NSCLC. RESULTS: All three IHC protocols showed congruent results. Only 1/25 FISH-positive NSCLC (4%) was false negative by IHC. For all three IHC protocols the sensitivity, specificity, positive (PPV) and negative predictive values (NPV) compared to FISH were 96%, 100%, 100% and 97.8%, respectively. In the prospective cohort 3/32 FISH-positive (9.4%) and 2/271 FISH-negative (0.7%) NSCLC were false negative and false positive by IHC, respectively. In routine diagnostics the sensitivity, specificity, PPV and NPV of IHC compared to FISH were 90.6%, 99.3%, 93.5% and 98.9%, respectively. CONCLUSIONS: 5A4 and D5F3 are equally well suited for detecting ALK-rearranged NSCLC. BenchMark and BOND-MAX immunostainers can be used for IHC with 5A4. True discrepancies between IHC and FISH results do exist and need to be addressed when implementing IHC in an ALK-testing algorithm.

Training primary care physicians in shared decision making for colorectal cancer screening : Insights from the first statewide colorectal cancer screening program in Switzerland

Background: The State of Vaud has launched the first population-based, organized, colorectal cancer screening program in Switzerland for the population aged 50 to 69. Each primary care physician (PCP) has been invited to participate in an interactive session preparing them to enroll patients in the screening program. We aimed at testing the impact of an interactive seminar for PCPs on their intention to discuss the options of no screening, screening with the fecal-immunological test (FIT) and colonoscopy. We measured attitude, intentions and knowledge through questionnaires filled by PCPs before and after a 2.5 hour-long interactive seminar. The main outcome was the proportion of physicians foreseeing to offer coloscopy vs FIT on an equal basis. Physicians estimated the proportion of their patients prescribed a fecal occult blood test (FOBT) vs coloscopy over the months before the seminar and after the interactive seminar. We used a clinical vignette to test for knowledge about screening indications. The interactive seminar included powerpoint presentations with quizzes and clickers, an 8-minute video presenting a shared decision making (SDM) consultation around CRC screening and distribution of educational materials such as a SDM decision aid and background epidemiological information.