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Aberrant activation of the PI3K pathway is one of the commonest oncogenic events in human cancer. AKT is a key mediator of PI3K oncogenic function, and thus has been intensely pursued as a therapeutic target. Multiple AKT inhibitors, broadly classified as either ATP-competitive or allosteric, are currently in various stages of clinical development. Herein, we review the evidence for AKT dependence in human tumours and focus on its therapeutic targeting by the two drug classes. We highlight the future prospects for the development and implementation of more effective context-specific AKT inhibitors aided by our increasing knowledge of both its regulation and some previously unrecognised non-canonical functions.

Background AKT, a critical effector of the phosphoinositide 3-kinase (PI3K) signalling cascade, is an intensely pursued therapeutic target in oncology. Two distinct classes of AKT inhibitors have been in clinical development, ATP-competitive and allosteric. Class-specific differences in drug activity are likely the result of differential structural and conformational requirements governing efficient target binding, which ultimately determine isoform-specific potency, selectivity profiles and activity against clinically relevant AKT mutant variants. Methods We have carried out a systematic evaluation of clinical AKT inhibitors using in vitro pharmacology, molecular profiling and biochemical assays together with structural modelling to better understand the context of drug-specific and drug-class-specific cell-killing activity. Results Our data demonstrate clear differences between ATP-competitive and allosteric AKT inhibitors, including differential effects on non-catalytic activity as measured by a novel functional readout. Surprisingly, we found that some mutations can cause drug resistance in an isoform-selective manner despite high structural conservation across AKT isoforms. Finally, we have derived drug-class-specific phosphoproteomic signatures and used them to identify effective drug combinations. Conclusions These findings illustrate the utility of individual AKT inhibitors, both as drugs and as chemical probes, and the benefit of AKT inhibitor pharmacological diversity in providing a repertoire of context-specific therapeutic options.

Preeclampsia is one of the leading causes of maternal and fetal morbidity and mortality. The objective of our study was to study risk factors and complications associated with severe preeclampsia requiring intensive care unit (ICU) admission Retrospective comparative study over a period from 1st of January 2015 to 1st of January 2019 in the University’s maternity unit of South Reunion (Indian Ocean). Our sampling included all preeclamptic patients who delivered in the Southern part of the island. Patients admitted to intensive care unit (ICU) and those who remained in the maternity unit (controls) were reviewed. Out of 482 preeclampsia cases, 94 women (19.5%) needed a transfer in ICU, of which only 21 (4.3%) needed invasive intensive care. Mean length of stay was 2.4 ± 2.1 days. ICU admission was associated with HELLP syndrome (OR 8.5 [4.9–14.9], pp=.01) and early onset of preeclampsia (pppp

Investigate potential factors associated with non-visualisation of tubal patency during Hysterosalpingo-Foam-Sonography (HyFoSy).This retrospective study was carried out at the medically assisted procreation centre of the University Hospital Centre in Reunion Island and focuses on HyFoSy performed between 01/01/2018 and 31/12/2020. We aimed to compare HyFoSy with bilateral tubal patency and those with a passage defect. Factors associated with non-visualisation of the contrast medium were investigated using comparison tests and logistic regression. Explanatory variables were patient history and ultrasound characteristics.137 eligible HyFoSy were included, of which 70.8% could be established for bilateral tubal patency. The assessment of tubal patency decreased in cases of overweight/obesity (62.5% versus 47.4%), previous pelvic surgery (17.5% versus 10.3%) and deep endometriosis (12.5% versus 5.2%), without significant difference. In the logistic regression model, a trend towards significance was observed for body mass index ≥ 25 kg/m² (OR 2.01 [95% CI 0.93-4.35], p= 0.07).HyFoSy as a first-line infertility test should be discussed in certain circumstances, due to risk of non-visualisation of tubal patency. In case of poor echogenicity, it should be performed by a trained ultrasonographer or a hysterosalpingography should be preferred. For tubo-pelvic pathologies, a laparoscopy should be discussed for diagnostic and therapeutic purposes. DISCIPLINE: gynaecology, infertility.

INTRODUCTION In Reunion Island (RUN), cervical cancer is the 4th most common cancer in women and standardized mortality rate is 4.8 for 100 000 women. It is preventable by HPV vaccination, yet only 8.1% of girls aged

HER1 and HER2 are frequently overexpressed in human tumors where they drive cellular proliferation. For this reason they are considered important targets in anticancer therapy with dual HER1/HER2 inhibitors being recently approved and marketed. In this paper we report the identification of a series of compounds with anticancer activity by a combined virtual screening approach on the kinase domains of HER1 and HER2. 6 hit compounds that present a sub- or low-micromolar activity in two cell-based assays, were initially identified and a subsequent design cycle led to the synthesis of a compound with nanomolar activity in the cell-based assays.

Objective In Reunion Island, the standardized mortality rate for cervical cancer is 4.8/100,000 women, twice higher than in Metropolitan France. For locally advanced disease, the standard of care includes a treatment by brachytherapy. Nevertheless, brachytherapy was not available on the Island before 2016. The objective of this study was to assess the impact of the management of patients with invasive cervical cancer on mortality in Reunion. Methods We have identified all the women hospitalized in one of the health care centers of the Island diagnosed with invasive cervical cancer between 01/01/2010 and 31/12/2015. The guidelines of the French Society of Gynecological Oncology (FSGO) were considered as the reference to evaluate professional practices. The characteristics that had an influence on global survival after log-rank test were included in a multivariate analysis according to the Cox Model. Results Retrospective analysis identified 303 women meeting inclusion criteria. The assessment of professional practices showed that the decisions on 11.6% of the patients discussed during multidisciplinary meetings, were not applied, consequentially leading to a decrease in survival (p = 0.001). A total of 156 patients (51.5%) were administered a treatment in accordance with the guidelines of the FSGO and had a better survival, even after multivariate analysis (HR 2.53 [CI 95% 1.55–4.14], p Conclusion The absence of treatment in accordance with the guidelines and decisions taken during multidisciplinary meetings and the absence of brachytherapy were associated to a higher mortality among patients with invasive cervical cancer in Reunion Island. We hope that the implementation of brachytherapy in Reunion will address these deficiencies.

Nestin, an intermediate filament protein and marker of undifferentiated cells, is expressed in several cancers. Nestin is important for neuronal survival and is a regulator of myogenesis but its function in malignancy is ambiguous. We show that nestin downregulation leads to a redistribution of phosphorylated focal adhesion kinase (pFAK, also known as PTK2) to focal adhesions and alterations in focal adhesion turnover. Nestin downregulation also leads to an increase in the protein levels of integrin α5β1 at the cell membrane, activation of integrin β1 and an increase in integrin clustering. These effects have striking consequences for cell invasion, as nestin downregulation leads to a significant increase in pFAK- and integrin-dependent matrix degradation and cell invasion. Our results indicate that nestin regulates the localisation and functions of FAK and integrin. Because nestin has been shown to be prevalent in a number of specific cancers, our observations have broad ramifications for the roles of nestin in malignant transformation.

Nestin, an intermediate filament protein and marker of undifferentiated cells, is expressed in several cancers. Nestin is important for neuronal survival and is a regulator of myogenesis but its function in malignancy is ambiguous. We show that nestin downregulation leads to a redistribution of phosphorylated focal adhesion kinase (pFAK, also known as PTK2) to focal adhesions and alterations in focal adhesion turnover. Nestin downregulation also leads to an increase in the protein levels of integrin α5β1 at the cell membrane, activation of integrin β1 and an increase in integrin clustering. These effects have striking consequences for cell invasion, as nestin downregulation leads to a significant increase in pFAK- and integrin-dependent matrix degradation and cell invasion. Our results indicate that nestin regulates the localisation and functions of FAK and integrin. Because nestin has been shown to be prevalent in a number of specific cancers, our observations have broad ramifications for the roles of nestin in malignant transformation.

The HER2 transmembrane receptor is a well-characterised predictive marker for trastuzumab benefit and may be associated with decreased benefit from endocrine therapy use. Despite the clinical effectiveness of anti-HER2 agents in such cases, resistance represents a significant limiting factor. Focal adhesion kinase (FAK) plays an important role in HER2 signalling, mediating downstream Akt activation in addition to HER2 cross talk with other growth factor receptors. In this study, we investigated the therapeutic potential of FAK in oestrogen receptor-positive (ER+)/HER2+ breast cancer using the novel FAK-specific inhibitor PF4554878 (‘PF878’). The activation of the FAK/HER2 signalling pathway was assessed in ER+/HER2− (MCF7 and T47D) and ER+/HER2+ (BT-474 and MDAMB361) breast cancer cells in the presence or absence of PF878 and PF878±trastuzumab. The effects of PF878 on cell growth as a monotherapy and in combination with trastuzumab were assessed using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and Coulter counting with isobologram analysis to determine synergy/additive effects. FAK activation (at Y861 but not at Y397) was highest in ER+/HER2+ cells, which also demonstrated the greatest sensitivity to PF878. As a monotherapy, PF878 prevented heregulin-induced MDA361 cell migration, but had no significant effect on cell growth. The treatment of ER+/HER2+ cells with PF878 and trastuzumab in combination resulted in the synergistic inhibition of cell proliferation. Underlying this was an abrogation of Akt activity and increased poly(ADP-ribose) polymerase cleavage, effects that were greatest in trastuzumab-refractory MDA361 cells. Collectively, these data support a role for FAK in ER+/HER2+ breast cancer, where its targeting has the potential to improve trastuzumab response. This is particularly important in the context of ER+/HER2+, trastuzumab-refractory disease, where FAK inhibition may present an important strategy to restore trastuzumab sensitivity.

Focal Adhesion Kinase (FAK) is an intracellular kinase known to mediate integrin signalling following cell adhesion to the extracellular matrix. FAK is also implicated in invasive signalling pathways downstream of growth factor receptors including the HER2. Cross talk between tumor and stroma can result in the activation of growth factor signalling pathways and thus may play a significant role in promoting tumor progression and spread. In this study, we have investigated the metastatic responses of HER2+ breast cancer cells to fibroblasts and whether FAK is involved in these events. Conditioned medium derived from human lung fibroblast MRC-5 cells was used to stimulate Her2+ SKBr3 breast cancer cells in the presence or absence of FAK inhibitor, PF271, or after FAK gene knockdown, prior to determining changes in migration (Boyden Chamber assay), 3d matrix invasion, growth and FAK-mediated signalling. To compare the role of FAK with HER2 in these cells, the HER2 targeted agent, trastuzumab was additionally employed. Whilst fibroblast-conditioned medium (FCM) did not affect the growth of SKBr3 cells or their HER2- negative, ER+ counterparts MCF7 cells, FCM significantly stimulated SKBr3 cell migration (∼10 fold vs control) and promoted invasive dissociation of 3d SKBr3 cultures. FCM treatment of SKBr3 cells resulted in rapid (within 5 minutes) activation of MAPK and AKT and increased phosphorylation of the HER4 receptor and FAK (Y861). FCM also promoted an increase in STAT3 (Y704) activity with an accompanying re-distribution to sites of membrane ruffling and to the nucleus. Pharmacological inhibition of FAK, or FAK siRNA, in SKBr3 cells attenuated FCM-mediated FAK activity and suppressed STAT3 activation and subcellular re-distribution and increased the expression of E-Cadherin. Correspondingly, FCM treatment of PF271 or FAKsiRNA- treated SKBr3 cells poorly elicited migratory and invasive responses. Importantly, suppression of HER2 using trastuzumab did not significantly antagonise these FCM responses. Taken together, these results suggest that FAK plays a role in the signalling stimulated by fibroblast- derived stimulators of migration and invasion through a mechanism involving STAT3. These highlight the importance of understanding tumor-stromal interactions and support the potential of FAK as a novel therapeutic target in HER2+ breast cancer particularly in the context of tumor stroma interactions where it may suppress stromal-induced tumor signalling that can contribute to progression and spread. Citation Format: Glorianne Lazaro, Chris Smith, Stephen Hiscox. Focal adhesion kinase (FAK) mediates fibroblast-induced HER2+ breast cancer cell migration and invasion through a mechanism involving Stat3. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1165. doi:10.1158/1538-7445.AM2014-1165