The study was supported by a research grant by the COVID "3×1 project", BREMBO S.p.A., Bergamo, Italy (TB) and by AIRC 5×1000 call "Metastatic disease: the key unmet need in oncology" to MYNERVA project, #21267 (MYeloid NEoplasms Research Venture AIRC). A detailed description of the MYNERVA project is available at https://progettomynerva.it (AMV, PG). The study was also supported by HARMONY PLUS, which is funded through the Innovative Medicines Initiative (IMI), Europe's largest public-private initiative aiming to speed up the development of better and safer medicines for patients. The HARMONY Alliance has received funding from IMI 2 Joint Undertaking and is listed under grant agreement No. 945406. This Joint Undertaking receives support from the European Union's Horizon 2020 Research and Innovation Programme and the European Federation of Pharmaceutical Industries and Associations (EFPIA). IMI supports collaborative research projects and builds networks of industrial and academic experts in order to boost pharmaceutical innovation in Europe.
NKX2 homeobox family proteins have a role in cancer development. Here we show that NKX2-3 is overexpressed in tumour cells from a subset of patients with marginal-zone lymphomas, but not with other B-cell malignancies. While Nkx2-3-deficient mice exhibit the absence of marginal-zone B cells, transgenic mice with expression of NKX2-3 in B cells show marginal-zone expansion that leads to the development of tumours, faithfully recapitulating the principal clinical and biological features of human marginal-zone lymphomas. NKX2-3 induces B-cell receptor signalling by phosphorylating Lyn/Syk kinases, which in turn activate multiple integrins (LFA-1, VLA-4), adhesion molecules (ICAM-1, MadCAM-1) and the chemokine receptor CXCR4. These molecules enhance migration, polarization and homing of B cells to splenic and extranodal tissues, eventually driving malignant transformation through triggering NF-κB and PI3K-AKT pathways. This study implicates oncogenic NKX2-3 in lymphomagenesis, and provides a valid experimental mouse model for studying the biology and therapy of human marginal-zone B-cell lymphomas. ; This work was supported by Grants from the Instituto de Salud Carlos III (ISCIII), Spanish Ministry of Economy and Competitiveness, FIS-PI12/00202 (to J.A.M.-C.), RTICC-RD12/0036/0063 (to J.A.M-C.), RTICC-RD12/0036/0068 (to M.J.C and F.P.), RTICC-RD12/0036/0022 (to J.L.F-L.), RTICC-RD12/0036/0070 (to J.C.), RTICC-RD12/0036/0010 (to B.B.), RTICC- RD12/0036/0044 (to M.J.B.) and RTICC-RD12/0036/0069 (to J.M.H.R. and M.G.); by Worldwide Cancer Research project grant 15-1322 (to J.A.M.-C., Y.R.C. and M.-Q.D.); by BFU2011-30097 (to Y.R.C); by MINECO SAF2013-45787-R and Marie Curie Programme FP7-PIIF-2012-328177 (to S.R.); by the French-Spanish CITTIL project (to F.P., X.A., J.A.M.-C., C.B. and P. Brousset); by SAF2012-32810, SAF2014-57791-REDC; PIE14/00066, BIO/SA32/14 and CSI001U14 (to I.S.G); by FIS-ISCIII projects PI13/00160 and PI14/00025, and Fundación Inocente Inocente (to C.C.); by Deutsche Krebshilfe, Molecular Mechanisms in Malignant Lymphomas Network Project (to R.S.); by the Institut Universitaire de France (to P. Brousset); by the Broad Medical Research Program of The Eli and Edythe Broad Foundation and the Hungarian Scientific Research Fund (OTKA K108429) (to P. Balogh); by pre- and post-doctoral fellowships from the Foundation for Applied Medical Research (to M.M.V. and E.F.R., respectively); and by a post-doctoral fellowship from the Basque Government (to I.M.-G.). All Spanish funding is co-sponsored by theEuropean Union FEDER program
Background: Adult T cell acute lymphoblastic leukemia (T-ALL) is a rare disease that affects less than 10 individuals in one million. It has been less studied than its cognate pediatric malignancy, which is more prevalent. A higher percentage of the adult patients relapse, compared to children. It is thus essential to study the mechanisms of relapse of adult T-ALL cases. Results: We profile whole-genome somatic mutations of 19 primary T-ALLs from adult patients and the corresponding relapse malignancies and analyze their evolution upon treatment in comparison with 238 pediatric and young adult ALL cases. We compare the mutational processes and driver mutations active in primary and relapse adult T-ALLs with those of pediatric patients. A precise estimation of clock-like mutations in leukemic cells shows that the emergence of the relapse clone occurs several months before the diagnosis of the primary T-ALL. Specifically, through the doubling time of the leukemic population, we find that in at least 14 out of the 19 patients, the population of relapse leukemia present at the moment of diagnosis comprises more than one but fewer than 108 blasts. Using simulations, we show that in all patients the relapse appears to be driven by genetic mutations. Conclusions: The early appearance of a population of leukemic cells with genetic mechanisms of resistance across adult T-ALL cases constitutes a challenge for treatment. Improving early detection of the malignancy is thus key to prevent its relapse. ; The authors would like to thank the Asociación Española Contra el Cáncer (AECC) for financially supporting this project (GC16173697BIGA). N.L.-B. acknowledges funding from the European Research Council (consolidator grant 682398) and the ERDF/Spanish Ministry of Science, Innovation and Universities–Spanish State Research Agency/DamReMap Project (RTI2018-094095-B-I00). S. G work is supported by the European Union's Horizon 2020 research and innovation program under the Marie Skłodowska-Curie grant agreement No. 754510. I. S is supported by FPI fellowship from Spanish Ministry of Economy and Competitiveness (project reference SAF2015-66084-R). V.G-H. is supported by the AECC (project reference GC16173697BIGA-9). IRB Barcelona is a recipient of a Severo Ochoa Centre of Excellence Award from the Spanish Ministry of Economy and Competitiveness (MINECO; Government of Spain) and is supported by CERCA (Generalitat de Catalunya).
