Inactivation of the retinoblastoma protein (pRB) by mutations or abnormal phosphorylation is a mechanism by which tumour cells can subdue normal growth control. Among molecules involved in control of pRB phosphorylation, cyclin D1 and E have been found to be deregulated and overexpressed in various types of cancers. In order to study the cell cycle regulatory mechanisms in breast cancer, we have analysed the protein expression of cyclin D1 and E in 114 tumour specimens from patients with primary breast cancer using Western blotting. Twenty-®ve out of 34 tumours with overexpression of cyclin E showed uniform low cyclin D1 expression, and by immunohistochemical analysis of pRB we present evidence for the existence of pRB defects in approximately 40% of these tumours in contrast to no pRB defects in the other group of tumours. This result was supported by a high protein expression of the cyclindependent kinase inhibitor p16 in 44% of the tumours with high cyclin E and low D1 expression, and all immunohistochemical pRB defect tumours showed a high p16 protein level. Additionally, an abnormal low pRB phosphorylation in relation to a high proliferative activity and loss of heterozygosity of the retinoblastoma susceptibility gene locus were found in all but one tumour with immunohistochemical defect pRB. Interestingly, tumours with high cyclin E and low D1 expression were generally oestrogen receptor negative suggesting a role for cell cycle regulators in the mechanisms leading to oestrogen independent tumour growth. Furthermore, the prognosis di ered markedly for the patients in the various groups of tumours, indicating that the heterogeneous nature of breast cancer pathogenesis and the clinical course in part could be explained by di erent and distinctive sets of cell cycle defects.
Cell cycle deregulation is frequently observed in tumors and has moreover been proposed to be a requirement for tumor development. By analyzing the expression of p27 by immunohistochemistry in 100 primary breast tumors and combining the analyses with our earlier characterization of cyclin E, D1, p16, and the retinoblastoma protein (pRB), we have been able to cover the majority of potential G1-S transition defects and observed that 90% of the tumors had alterations in one or several cell cycle regulatory proteins. Considerable variations in protein levels were found among tumors, with low p16 expression as the most common alteration followed by cyclin E or cyclin D1 overexpression, low p27 expression or pRB inactivation in decreasing prevalence. Tumors were grouped according to observed combinations of defects and the proliferative capacity was determined for each group by analyzing Ki-67 labeling index. Low proliferation was observed in tumors with: low p16; high cyclin D1 with normal or high p16 expression; and in tumors without cell cycle defects. Tumors with high cyclin E/low p27 or pRB defects showed higher proliferation. The survival differed noticeably for patients with various combinations of cell cycle defects, and four distinctive clusters were identified showing significantly different breast cancer specific survival (p<0.0001) for both node-positive (p = 0.0006) and node-negative patients (p<0.0001). In summary, we have shown that G1-S transition defects are nearly obligatory in breast tumors and that the specific type of cell cycle defect influences the clinical behavior of the tumor.
Background: The objective of the Swedish cleft lip and palate (CLP) registry is to promote quality control, research and improvement of treatment, by comparison of the long-term results of surgery, orthodontics and speech from all six Swedish CLP centres. The purpose of the study was to investigate the coverage and reporting degree of the Swedish CLP registry, and to describe the design of the registry and discuss questions of reliability and validity of the data included. Methods: All six Swedish CLP centres participate in the registry. All children in Sweden with cleft lip and/or cleft palate, born from 2009 onwards, are included in the registry. Baseline data such as cleft type (ICD-10 diagnosis), heredity, birth weight and additional deformities and/or syndromes, as well as pre-surgical treatment, are recorded at first visit. Data on surgical treatment are recorded continuously. Treatment outcome regarding dentofacial development and speech are recorded at follow-ups at 5, 10, 16 and 19 years of age. Data on dentofacial development are also recorded 1 year after orthognathic surgery. In addition, data on babbling and speech are recorded at 18 months of age. Coverage degree and reporting degree of surgery was assessed by comparison with registrations in the Swedish Central patient registry. Reporting degree of orthodontic and speech registrations at 5 years of age was assessed by comparison with registrations at baseline. Results: The average coverage degree for children born 2009 to 2018 was 95.1%. For cleft-related surgeries, the average reporting degree was 92.4%. Average reporting degree of orthodontic registrations and speech registrations at age 5 years was 92 and 97.5% respectively. Conclusion: In order to achieve valid and reliable data in a healthcare quality registry, the degree of coverage and reporting needs to be high, the variables included should be limited and checked for reliability, and the professionals must calibrate themselves regularly. The Swedish CLP registry fulfils these requirements.
Background The objective of the Swedish cleft lip and palate registry (CLP registry) is to promote quality control, research and improvement of treatment, by the comparison of long-term results. The aim was to compare data from the CLP registry among the six treatment centres, regarding data on surgery and speech outcomes at 5 years of age. Methods The participants were 430 children born in Sweden from 2009 to 2014, with cleft palate with or without cleft lip and without known syndromes and/or additional malformations. The number of primary and secondary palatal surgeries up to 5 years of age, timing of the last primary palatal surgery, percentage consonants correct, percentage non-oral speech errors and perceived velopharyngeal competence at 5 years were assessed. Multivariable binary logistic regression adjusted for sex and cleft type was used to compare results between the six centres. Results At one centre (centre 4), the palate was closed in one to three stages, and at the remaining centres in one or two stages. At centre 4, more children underwent a higher number of palatal surgeries, and the last primary palatal surgery was performed at a higher age. Children in centre 4 were also less likely to achieve ≥86% correct consonants (OR = 0.169, P = < 0.001), have no non-oral speech errors (OR = 0.347, P = < 0.001), or have competent or marginally incompetent velopharyngeal competence (OR = 0.244, P = < 0.001), compared to the average results of the other centres. No clear association between patient volume and speech outcome was observed. Conclusions The results indicated the risk of a negative speech result if the last primary palatal surgery was performed after 25 months of age. Whether the cleft in the palate was closed in one or two stages did not affect speech outcome. The Swedish CLP registry can be used for open comparisons of treatment results to provide the basis for improvements of treatment methods. If deviating negative results are seen consistently at one centre, this information should be acted upon by further investigation and analysis, making changes to the treatment protocol as needed.
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