Fertility Among Female Survivors of Childhood, Adolescent, and Young Adult Cancer: Protocol for Two Pan-European Studies (PanCareLIFE).

BACKGROUND: Despite a significant number of studies on female fertility following childhood, adolescent, and young adult (CAYA) cancer, studies establishing precise (dose-related) estimates of treatment-related risks are still scarce. Previous studies have been underpowered, did not include detailed treatment information, or were based on self-report only without any hormonal assessments. More precise assessments of who is at risk for sub- or infertility are needed. OBJECTIVE: The objective of our study is to describe the design and methods of 2 studies on female fertility (a cohort study and a nested case-control study) among female survivors of CAYA cancer performed within the European PanCareLIFE project. METHODS: For the cohort study, which aims to evaluate the overall risk of fertility impairment, as well as the risk for specific subgroups of female CAYA cancer survivors, 13 institutions from 9 countries provide data on fertility impairment. Survivors are defined as being fertility impaired if they meet at least one of 8 different criteria based on self-reported and hormonal data. For the nested case-control study, which aims to identify specific treatment-related risk factors associated with fertility impairment in addition to possible dose-response relationships, cases (fertility impaired survivors) are selected from the cohort study and matched to controls (survivors without fertility impairment) on a 1:2 basis. RESULTS: Of the 10,964 survivors invited for the cohort study, data are available from 6619 survivors, either questionnaire-based only (n=4979), hormonal-based only (n=72), or both (n=1568). For the nested case-control study, a total of 450 cases and 882 controls are identified. CONCLUSIONS: Results of both PanCareLIFE fertility studies will provide detailed insight into the risk of fertility impairment following CAYA cancer and diagnostic- or treatment-related factors associated with an increased risk. This will help clinicians to adequately counsel both girls and young women, who are about to start anticancer treatment, as well as adult female CAYA cancer survivors, concerning future parenthood and to timely refer them for fertility preservation. Ultimately, we aim to empower patients and survivors and improve their quality of life. REGISTERED REPORT IDENTIFIER: RR1-10.2196/10824.

Constitutive activation of the Wnt/beta-catenin signalling pathway in acute myeloid leukaemia.

The beta-catenin protein is at the core of the canonical Wnt signalling pathway. Wnt stimulation leads to beta-catenin accumulation, nuclear translocation and interaction with T-cell factor/lymphoid enhancer factor (TCF/LEF) transcription factors to regulate genes important for embryonic development and proliferation. Wnt/beta-catenin can promote stem cell self-renewal and is dysregulated in colon carcinoma. We have examined the role of the Wnt pathway in the development of acute myeloid leukaemia (AML) and find that the beta-catenin protein is readily detected in primary AML samples. Using transfection of a TCF/LEF reporter construct into primary AML cells and normal human progenitors, we find increased reporter activity in 16/25 leukaemia samples. Retrovirally mediated expression of a mutant active beta-catenin in normal progenitors preserves CD34 expression and impairs myelomonocytic differentiation. Activation of TCF/LEF signalling decreases factor withdrawal-induced apoptosis of normal progenitors. A significant proportion of AML cases show aberrant expression of components of the Wnt pathway including Wnt-1, Wnt-2b and LEF-1. These results provide evidence for the involvement of the Wnt/beta-catenin pathway in the pathogenesis of AML.

Gö6976 is a potent inhibitor of the JAK 2 and FLT3 tyrosine kinases with significant activity in primary acute myeloid leukaemia cells.

Aberrant activation of Janus kinase/signal transducers and activators of transcription (JAK/STAT) signalling is implicated in a number of haematological malignancies and effective JAK inhibitors may be therapeutically useful. We found that Gö6976, an indolocarbazole inhibitor of the calcium-dependent isozymes of protein kinase C (PKC), inhibited interleukin 3/granulocyte-macrophage colony-stimulating factor-induced signalling, proliferation and survival whereas Gö6983, a broad spectrum PKC inhibitor, had no such effects. Gö6976 was found to be a direct and potent inhibitor of JAK2 in vitro. Gö6976 also inhibited signalling, survival and proliferation in cells expressing the leukaemia-associated TEL-JAK2 fusion protein and the myeloproliferative disorder (MPD)-associated JAK2 V617F mutant. In primary acute myeloid leukaemia (AML) cells, incubation with Gö6976 reduced constitutive STAT activity in all cases studied. In addition, Akt and mitogen-activated protein kinase phosphorylation were reduced in 4/5 FLT3-internal tandem duplication (ITD) positive AML cases and 7/13 FLT3-wild-type (WT) cases. Expression of FLT3-WT, ITD and D835Y in 32D cells showed that Gö6976 is also a potent inhibitor of WT and mutant FLT3. In AML cells, Gö6976 reduced the survival to 55 +/- 5% of control in FLT3-ITD cases and to 69 +/- 5% in FLT3-WT samples. These data may help identify clinically useful compounds based on the structure of Gö6976, which can be employed for the treatment of MPDs as well as AML.

Lack of effect of the human GM-CSF analog E21R on the survival of primary human acute myeloid leukemia cells.

The granulocyte-macrophage colony-stimulating factor (GM-CSF) analog E21R binds to the GM-CSF receptor complex with low affinity and acts as a competitive antagonist. In addition, it has been reported to be a potent direct activator of apoptosis in primary human acute myeloid leukemia (AML) cells. We have confirmed the ability of E21R to neutralize the biologic effects of GM-CSF and investigated its activity on primary AML blasts. We find that it failed to induce cell death in blast cells from 23 separate AML cases treated in vitro at concentrations of E21R up to 30 microg/mL. Significant cell death resulted in all cases after incubation with cytosine arabinoside. The lack of effect of E21R on AML blasts was unlikely to be due to an absence of functional GM-CSF receptors because 13 cases demonstrated an increase in cell number with the addition of exogenous GM-CSF. These results do not support the use of E21R for the treatment of AML.