[Screening for cancer]. / Screening für Krebserkrankungen.

A low birth rate in addition to an increasing life expectancy within the context of an aging population characterize the current demographic situation in Germany. Cancer is primarily a disease of old age and the frequency increases with an expanding older population. In 2013, cancer was the second most common cause of death in Germany. With the aid of screening examinations cancer should be detected in the early stages so that suitable therapeutic measures can be initiated. In Germany, screening is currently offered for breast, cervical, colorectal, skin and prostate cancer and is covered by the statutory health insurance. Mammography screening is the only organized screening program in Germany. Eligible women are regularly invited to attend this program, which is not the case for the other types of cancer screening. In accordance with the Cancer Screening and Registry Act (KFRG) of 2013, colorectal and cervical cancer screening will also be implemented as organized screening programs in the future. As is the case in the mammography screening program, those eligible to participate will receive an invitation letter and the new programs are to be continually monitored, documented and evaluated.

[Early detection of cervical cancer in Germany: evidence and implementation]. / Früherkennung des Zervixkarzinoms in Deutschland : Evidenz und Umsetzung.

Cervical cancer is the third most common cancer among women worldwide, with an estimated 529,000 new cases in 2008. The incidence of cervical cancer in Germany is still among the highest in Western Europe. For more than 40 years women in Germany have had legal and free access to a conventional cytologic smear test starting at the age of 20 years. The introduction of the Pap smear subsequently led to a reduction in the incidence and mortality of cervical cancer. However, the low sensitivity of the Pap smear and the evidence regarding human papillomavirus (HPV) in the context of cervical cancer have led to a critical view of the existing early detection of cervical cancer. In the meantime, new screening methods have been developed and different HPV tests, liquid-based cytology, and novel biomarkers have become available. Several randomized studies have investigated HPV testing as a primary cervical cancer screening test, generating a large body of evidence. It is expected that a combination of HPV testing and cytology will improve cervical cancer screening. In the near future, the early detection of cervical cancer in Germany will be restructured on the basis of the German National Cancer Plan as well as the new Cancer Screening and Registers Act (KFRG). The European guidelines for quality assurance in cervical cancer screening will be taken into account, and an organized, population-based, and quality-assured cervical cancer screening program will be implemented.

HPV infection awareness and self-reported HPV vaccination coverage in female adolescent students in two German cities.

Low levels of human papillomavirus (HPV) awareness and knowledge have been observed in the few studies conducted among school-going adolescents. Such data are lacking in Germany. To assess awareness of HPV and of vaccination status among girls attending grades 8-13 in Bremen and Bremerhaven, two German cities. Participants completed a questionnaire in school including questions on demographic characteristics, about HPV awareness and on vaccination status. We analysed the relationship between awareness of HPV, of vaccination status and vaccine uptake and several variables including age and migrant background using univariate and multivariate logistic regression. Six hundred and thirty-two girls aged 12-20 years completed the questionnaire. 50 % had no awareness of HPV, 12 % reported being vaccinated against HPV and 57 % did not know whether or not they were vaccinated against HPV. In multivariate analyses, ever had sex was associated with awareness of HPV, and ever been to a gynaecologist with awareness of vaccination status. Our results may be an indication that female adolescents in Germany are not adequately informed and counselled about HPV and associated issues.

[Comparison of ICD coding between mortality statistics and study-intern retrospective re-coding]. / Vergleich von ICD-Kodierungen zwischen Mortalitätsstatistik und studieninterner retrospektiver Nachkodierung.

OBJECTIVES: The aim of this study was to assess agreement between study-intern nosologist death certificate coding and official mortality statistics ICD codes. METHODS: During the follow-up of a historical cohort study conducted in Germany, original death certificates were obtained for deceased cohort members and ICD coded by a study-intern nosologist. Additionally, ICD codes for these study subjects were obtained from a state statistical office responsible for mortality statistics. A weighted inter-observer agreement for these two sources was calculated. RESULTS: In total, 406 ICD codes were available from both sources. 219 (53.9%) of these ICD codes completely agreed on the highest level possible (three- or four-digits). Agreement was found on the three-digit level with a difference at the fourth digit in 42 (10.3%) causes of death. Agreement within diagnosis groups or within chapters of disease was found in 21 (5.2%) and 49 (12.1%) causes of death, respectively. The weighted kappa for the overall inter-observer agreement was 0.67 [95% confidence interval (CI): 0.63-0.71]. Within chapters of disease, agreement was higher for neoplasms (kappa=0.88; 95% CI: 0.83-0.93) than for cardiovascular diseases (kappa=0.69; CI: 0.62-0.76). CONCLUSIONS: Overall level of agreement between the two coding sources was not very good. In Germany, the quality of coding has not improved substantially in the past two decades. The introduction of automatic coding systems, multicausal coding and a mortality register could improve the quality of ICD coding in Germany.

[New research avenues in exploring causes of death in Germany via regional statistical offices as exemplified by a retrospective cohort study]. / Neue Möglichkeit der Recherche von Todesursachen in Deutschland über Statistische Landesämter am Beispiel einer retrospektiven Kohortenstudie.

In retrospective epidemiological cohort studies the mortality rate of a cohort exposed to certain agents under investigation is compared to the mortality rate of the general population. In Germany, vital status of the cohort is followed up via local population registries. Cause of death of deceased members of the cohort is obtained from death certificates by local health authorities. Since storage time for death certificates is short in some Federal German states, causes of death cannot be obtained if death occurred before storage deadline. Recently it became possible to obtain the cause of death from regional statistical offices. Initial co-operation has been established with the statistical offices of North Rhine Westphalia and Berlin. For a cohort study in the chemical industry, the initially low proportion of causes of death obtained from local health authorities (44.8 %) was increased by 30 % to 74.0 % after obtaining ICD coded causes of death from two regional statistical offices. Further advantages of this new data source are reduction in duration of inquiry time and of overall cost.

TP53 polymorphism, HPV infection, and risk of cervical cancer.

The role of a polymorphism at position 72 of the tumor suppressor gene TP53 in the development of cervical cancer is not well established. The arginine variant of the p53 protein could be more susceptible to degradation by human papillomavirus (HPV) E6 protein than the protein containing proline. Recent studies show controversial results. We investigated a possible association between TP53 polymorphism and cervical cancer in a Peruvian population with high prevalence of HPV infection. HPV status and TP53 polymorphism were determined for 119 cases of invasive cervical cancer and 127 control women from Peru. HPV infection was detected by PCR of cervical cells or tumor biopsies. For determination of TP53 polymorphism, exon 4 of the TP53 gene was amplified by PCR, and DNA was subsequently subjected to restriction enzyme digest. Associations between TP53 polymorphism, HPV infection, and cervical cancer were assessed using logistic regression. Women homozygotes for arginine had a 2.2-fold increased risk (95% confidence interval: 0.6-7.6) for cervical cancer. The odds ratio for women heterozygotes for Arg/Pro was 3.5 (95% confidence interval: 0.9-14). Similarly increased risks were found when restricting analysis to HPV-positive women only. The distribution of TP53 genotypes in this Peruvian population was comparable with that found in Caucasians. Our results cannot rule out an association between the TP53 polymorphism at codon 72, HPV infection, and the etiology of cervical cancer.

Human papillomavirus infection and invasive cervical cancer in Paraguay.

HPV types 16 and 18 have been categorized as human carcinogens based on their strong associations with cervical cancer in previous case-control studies. Recent IARC studies in the Philippines, Thailand and Morocco show strong associations between invasive cervical cancer and less common HPV types, including HPV 31, 33, 45, 51, 52 and 58. We present results of a further IARC case-control study conducted in Asunción, Paraguay, to examine the association between specific HPV types and invasive cervical cancer as well as risk factors other than HPV. One-hundred thirteen incident histologically confirmed invasive cervical cancer cases and 91 age-matched hospital controls were recruited. A standardized questionnaire was administered to investigate known and suspected risk factors for cervical cancer. For HPV status determination, cervical biopsy specimens from case subjects and exfoliated cervical cells from control subjects were obtained. HPV DNA was ascertained using a GP5+/6+ PCR-based assay capable of detecting more than 33 HPV types. Overall HPV prevalence was 97% in the cervical cancer cases and 20% in the control subjects. As a single infection, HPV 16 was the predominant type with a prevalence of 48% among case subjects and 5.5% among control subjects. Significant associations with the risk of cervical cancer were detected as follows: any HPV type (OR = 114; 95% CI: 36-361); HPV 16 (OR = 910); HPV 18 (infinite OR); HPV 31 (OR = 110); HPV 33 (OR = 261); HPV 45 (OR = 129); and HPV 58 (OR = 36). In the multivariate model, risk factors other than HPV significantly associated with cervical cancer risk were a higher number of lifetime sexual partners, lower educational status and never having had a Pap smear. Strong associations were found between invasive cervical cancer and specific HPV types 16, 18, 31, 33, 45 and 58.

In vitro selection of RNA aptamers that bind special elongation factor SelB, a protein with multiple RNA-binding sites, reveals one major interaction domain at the carboxyl terminus.

The SelB protein of Escherichia coli is a special elongation factor required for the cotranslational incorporation of the uncommon amino acid selenocysteine into proteins such as formiate dehydrogenases. To do this, SelB binds simultaneously to selenocysteyl-tRNA(Sec) and to an RNA hairpin structure in the mRNA of formiate dehydrogenases located directly 3' of the selenocysteine opal (UGA) codon. The protein is also thought to contain binding sites allowing its interaction with ribosomal proteins and/or rRNA. SelB thus includes specific binding sites for a variety of different RNA molecules. We used an in vitro selection approach with a pool completely randomized at 40 nt to isolate new high-affinity SelB-binding RNA motifs. Our main objective was to investigate which of the various RNA-binding domains in SelB would turn out to be prime targets for aptamer interaction. The resulting sequences were compared with those from a previous SELEX experiment using a degenerate pool of the wild-type formiate dehydrogenase H (fdhF) hairpin sequence (Klug SJ et al., 1997, Proc. Natl. Acad. Sci. USA 94:6676-6681). In four selection cycles an enriched pool of tight SelB-binding aptamers was obtained; sequencing revealed that all aptamers were different in their primary sequence and most bore no recognizable consensus to known RNA motifs. Domain mapping for SelB-binding aptamers showed that despite the different RNA-binding sites in the protein, the vast majority of aptamers bound to the ultimate C-terminus of SelB, the domain responsible for mRNA hairpin binding.

In vitro and in vivo characterization of novel mRNA motifs that bind special elongation factor SelB.

The special elongation factor SelB of Escherichia coli promotes selenocysteine incorporation into formate dehydrogenases. This is thought to be achieved through simultaneous binding to selenocysteyl-tRNASec and, in the case of formate dehydrogenase H, to an fdhF mRNA hairpin structure 3' adjacent to the UGA selenocysteine codon. By in vitro selection, novel RNA sequences ("aptamers"), which can interact tightly and specifically with SelB, were isolated from an RNA library. The library was comprised of mutagenized variants of the wild-type fdhF mRNA hairpin. One-half of the selected sequences contained the apical stem-loop of the fdhF mRNA hairpin highly conserved. Some of the aptamers showed deviations in the primary sequence within this region of the wild-type fdhF hairpin motif while still binding with high affinity to SelB. Binding studies performed with truncated versions of SelB revealed that aptamers binding to different sites on the protein have been selected. To dissect SelB binding to the fdhF hairpin from the overall biological function of this complex, four selected aptamers were analyzed in vivo for UGA readthrough in a lacZ fusion construct. Among these, one promoted UGA readthrough in vivo. Three of the aptamers, however, were drastically reduced or unable to replace the fdhF mRNA hairpin in vivo, despite the similar secondary structure and binding affinities of these RNAs compared with the wild-type motif. This finding implies functions of the fdhF hairpin that go beyond the mere tethering of selenocysteyl-tRNASec to the UGA codon.

All you wanted to know about SELEX.

In vitro selection, or SELEX, is a technique that allows the simultaneous screening of highly diverse pools of different RNA or DNA (dsDNA or ssDNA) molecules for a particular feature. Different examples from a great variety of applications of in vitro selection experiments are described and a detailed overview of the method and its variations will be given. Some especially conclusive in vitro selection experiments are discussed in detail to illustrate the potential power and diversity of this method. Potential restrictions of the methods and possible ways to overcome them are pointed out.

Binding of epidermal growth factor to its receptor is affected by membrane phospholipid environment.

Cells of epithelial origin generally require ethanolamine to grow in culture; when these cells are grown without ethanolamine, the phosphatidylethanolamine content of their membrane phospholipid becomes 1/2 to 1/3 of the normal amount, and growth stops. We have hypothesized that growth ceases because the phospholipid environment becomes unsuitable for membrane-associated function. Using ethanolamine-requiring rat mammary cells, we have investigated the possible effect of phosphatidylethanolamine deficiency on the binding characteristics of epidermal growth factor. Apparent dissociation constant for the high-affinity sites in cells having normal membrane phospholipid was 1.7 X 10(-10) M, whereas that of phosphatidylethanolamine-deficient cells was 2.7 X 10(-10) M: the difference was small, but significant. Pretreatment with phorbol ester caused the loss of high-affinity sites in cells having normal membrane, whereas binding characteristics of epidermal growth factor became refractory to the pretreatment in phosphatidylethanolamine-deficient cells. In addition, the rate of internalization of bound epidermal growth factor in phosphatidylethanolamine-deficient cells was about 1/4 of normal cells. Further, whether cells had normal or phosphatidylethanolamine-deficient membranes seemed to affect the phosphorylation patterns of membrane proteins in response to epidermal growth factor or phorbol ester. These results suggest that membrane phospholipid environment affects the activity of the epidermal growth factor receptor.