Clonal evolution in tyrosine kinase inhibitor-resistance: lessons from in vitro-models

IntroductionResistance in anti-cancer treatment is a result of clonal evolution and clonal selection. In chronic myeloid leukemia (CML), the hematopoietic neoplasm is predominantly caused by the formation of the BCR::ABL1 kinase. Evidently, treatment with tyrosine kinase inhibitors (TKIs) is tremendously successful. It has become the role model of targeted therapy. However, therapy resistance to TKIs leads to loss of molecular remission in about 25% of CML patients being partially due to BCR::ABL1 kinase mutations, while for the remaining cases, various other mechanisms are discussed.MethodsHere, we established an in vitro-TKI resistance model against the TKIs imatinib and nilotinib and performed exome sequencing.ResultsIn this model, acquired sequence variants in NRAS, KRAS, PTPN11, and PDGFRB were identified in TKI resistance. The well-known pathogenic NRAS p.(Gln61Lys) variant provided a strong benefit for CML cells under TKI exposure visible by increased cell number (6.2-fold, p < 0.001) and decreased apoptosis (-25%, p < 0.001), proving the functionality of our approach. The transfection of PTPN11 p.(Tyr279Cys) led to increased cell number (1.7-fold, p = 0.03) and proliferation (2.0-fold, p < 0.001) under imatinib treatment.DiscussionOur data demonstrate that our in vitro-model can be used to study the effect of specific variants on TKI resistance and to identify new driver mutations and genes playing a role in TKI resistance. The established pipeline can be used to study candidates acquired in TKI-resistant patients, thereby providing new options for the development of new therapy strategies to overcome resistance

Survey of young women's state of knowledge and perceptions about oral contraceptives in Germany

BACKGROUND: In Germany, we see a decline in the use of the oral contraceptive pill. Although there have been studies showing a lack of knowledge about the mode of action of the pill and alternative methods, the number of German women who feel well informed about the pill increased over recent years. At the same time, a trend to increasingly cover negative aspects of oral contraception has emerged in German journalism and social media. OBJECTIVE: This study aimed to consider the relationship between the source of information about the pill, subjective and objective knowledge, and how their interaction influences perceptions of the pill. STUDY DESIGN: An online survey was conducted of 18- to 29-year-old women to test their objective and subjective knowledge, their perception of oral contraceptives, and their trust in gynecologists. The recruitment took place online and in gynecologic practices. The survey opened in September 2020 and closed in April 2021. RESULTS: A total of 2470 women completed the survey. The most common sources of information were the internet (80%), the gynecologist (47%), and friends and family (47%). Women reporting the internet as a source of information were more likely to have lower perception and trust rates, and less likely to overestimate their own knowledge. The findings suggest that school or university as a source of information has a positive effect on decision-making and general attitude toward information received by gynecologists about oral contraceptives. Those with higher confidence in their knowledge are likely to have a more positive attitude and higher levels of trust. CONCLUSION: A feeling of uncertainty, instead of fixed assumptions gathered from unsophisticated sources, affects perception regarding oral contraceptives and trust toward gynecologists negatively. Gynecologists and educators should hence increase efforts to meet potential needs for discussing uncertainties to prevent further loss of confidence