Stable MOB1 interaction with Hippo/MST is not essential for development and tissue growth control.

The Hippo tumor suppressor pathway is essential for development and tissue growth control, encompassing a core cassette consisting of the Hippo (MST1/2), Warts (LATS1/2), and Tricornered (NDR1/2) kinases together with MOB1 as an important signaling adaptor. However, it remains unclear which regulatory interactions between MOB1 and the different Hippo core kinases coordinate development, tissue growth, and tumor suppression. Here, we report the crystal structure of the MOB1/NDR2 complex and define key MOB1 residues mediating MOB1's differential binding to Hippo core kinases, thereby establishing MOB1 variants with selective loss-of-interaction. By studying these variants in human cancer cells and Drosophila, we uncovered that MOB1/Warts binding is essential for tumor suppression, tissue growth control, and development, while stable MOB1/Hippo binding is dispensable and MOB1/Trc binding alone is insufficient. Collectively, we decrypt molecularly, cell biologically, and genetically the importance of the diverse interactions of Hippo core kinases with the pivotal MOB1 signal transducer.The Hippo tumor suppressor pathway is essential for development and tissue growth control. Here the authors employ a multi-disciplinary approach to characterize the interactions of the three Hippo kinases with the signaling adaptor MOB1 and show how they differently affect development, tissue growth and tumor suppression

COVID-19 Risk Factors for Cancer Patients: A First Report with Comparator Data from COVID-19 Negative Cancer Patients

none32siSimple SummaryThe COVID-19 pandemic has had a detrimental impact on cancer patients globally. Whilst there are several studies looking at the potential risk factors for COVID-19 disease and related death, most of these include non-cancerous patients as the COVID-19 negative comparator group, meaning it is difficult to draw hard conclusions as to the implications for cancer patients. In our study, we utilized data from over 2000 cancer patients from a large tertiary Cancer Centre in London. In summary, our study found that patients who are male, of Black or Asian ethnicity, or with a hematological malignancy are at an increased risk of COVID-19. The use of cancer patients as the COVID-19 negative comparator group is a major advantage to the study as it means we can better understand the true impact of COVID-19 on cancer patients and identify which factors pose the biggest risk to their likelihood of infection with SARS-CoV2.Very few studies investigating COVID-19 in cancer patients have included cancer patients as controls. We aimed to identify factors associated with the risk of testing positive for SARS CoV2 infection in a cohort of cancer patients. We analyzed data from all cancer patients swabbed for COVID-19 between 1(st) March and 31(st) July 2020 at Guy's Cancer Centre. We conducted logistic regression analyses to identify which factors were associated with a positive COVID-19 test. Results: Of the 2152 patients tested for COVID-19, 190 (9%) tested positive. Male sex, black ethnicity, and hematological cancer type were positively associated with risk of COVID-19 (OR = 1.85, 95%CI:1.37-2.51; OR = 1.93, 95%CI:1.31-2.84; OR = 2.29, 95%CI:1.45-3.62, respectively) as compared to females, white ethnicity, or solid cancer type, respectively. Male, Asian ethnicity, and hematological cancer type were associated with an increased risk of severe COVID-19 (OR = 3.12, 95%CI:1.58-6.14; OR = 2.97, 95%CI:1.00-8.93; OR = 2.43, 95%CI:1.00-5.90, respectively). This study is one of the first to compare the risk of COVID-19 incidence and severity in cancer patients when including cancer patients as controls. Results from this study have echoed those of previous reports, that patients who are male, of black or Asian ethnicity, or with a hematological malignancy are at an increased risk of COVID-19.openRussell, Beth; Moss, Charlotte L; Palmer, Kieran; Sylva, Rushan; D'Souza, Andrea; Wylie, Harriet; Haire, Anna; Cahill, Fidelma; Steel, Renee; Hoyes, Angela; Wilson, Isabelle; Macneil, Alyson; Shifa, Belul; Monroy-Iglesias, Maria J; Papa, Sophie; Irshad, Sheeba; Ross, Paul; Spicer, James; Kordasti, Shahram; Crawley, Danielle; Zaki, Kamarul; Sita-Lumsden, Ailsa; Josephs, Debra; Enting, Deborah; Swampillai, Angela; Sawyer, Elinor; Fields, Paul; Wrench, David; Rigg, Anne; Sullivan, Richard; Van Hemelrijck, Mieke; Dolly, SaoirseRussell, Beth; Moss, Charlotte L; Palmer, Kieran; Sylva, Rushan; D'Souza, Andrea; Wylie, Harriet; Haire, Anna; Cahill, Fidelma; Steel, Renee; Hoyes, Angela; Wilson, Isabelle; Macneil, Alyson; Shifa, Belul; Monroy-Iglesias, Maria J; Papa, Sophie; Irshad, Sheeba; Ross, Paul; Spicer, James; Kordasti, Shahram; Crawley, Danielle; Zaki, Kamarul; Sita-Lumsden, Ailsa; Josephs, Debra; Enting, Deborah; Swampillai, Angela; Sawyer, Elinor; Fields, Paul; Wrench, David; Rigg, Anne; Sullivan, Richard; Van Hemelrijck, Mieke; Dolly, Saoirs

Kinome screening for regulators of the estrogen receptor identifies LMTK3 as a new therapeutic target in breast cancer

Therapies targeting estrogen receptor α (ERα, encoded by ESR1) have transformed the treatment of breast cancer. However, large numbers of women relapse, highlighting the need for the discovery of new regulatory targets modulating ERα pathways. An siRNA screen identified kinases whose silencing alters the estrogen response including those previously implicated in regulating ERα activity (such as mitogen-activated protein kinase and AKT). Among the most potent regulators was lemur tyrosine kinase-3 (LMTK3), for which a role has not previously been assigned. In contrast to other modulators of ERα activity, LMTK3 seems to have been subject to Darwinian positive selection, a noteworthy result given the unique susceptibility of humans to ERα+ breast cancer. LMTK3 acts by decreasing the activity of protein kinase C (PKC) and the phosphorylation of AKT (Ser473), thereby increasing binding of forkhead box O3 (FOXO3) to the ESR1 promoter. LMTK3 phosphorylated ERα, protecting it from proteasomal degradation in vitro. Silencing of LMTK3 reduced tumor volume in an orthotopic mouse model and abrogated proliferation of ERα+ but not ERα- cells, indicative of its role in ERα activity. In human cancers, LMTK3 abundance and intronic polymorphisms were significantly associated with disease-free and overall survival and predicted response to endocrine therapies. These findings yield insights into the natural history of breast cancer in humans and reveal LMTK3 as a new therapeutic target