doi:10.1038/s41416-022-02093-xengJuste-Lanas, Y.Díaz-Valdivia, N.Llorente, A.Ikemori, R.Bernardo, A.Arshakyan, M.Borau, C.Ramírez, J.Ruffinelli, J. C.Nadal, E.Reguart, N.García-Aznar, J. M.Alcaraz, J.3D collagen migration patterns reveal a SMAD3-dependent and TGF-ß1-independent mechanism of recruitment for tumour-associated fibroblasts in lung adenocarcinomaART-2023-132682Background: The TGF-β1 transcription factor SMAD3 is epigenetically repressed in tumour-associated fibroblasts (TAFs) from lung squamous cell carcinoma (SCC) but not adenocarcinoma (ADC) patients, which elicits a compensatory increase in SMAD2 that renders SCC-TAFs less fibrotic. Here we examined the effects of altered SMAD2/3 in fibroblast migration and its impact on the desmoplastic stroma formation in lung cancer. Methods: We used a microfluidic device to examine descriptors of early protrusions and subsequent migration in 3D collagen gels upon knocking down SMAD2 or SMAD3 by shRNA in control fibroblasts and TAFs. Results: High SMAD3 conditions as in shSMAD2 fibroblasts and ADC-TAFs exhibited a migratory advantage in terms of protrusions (fewer and longer) and migration (faster and more directional) selectively without TGF-β1 along with Erk1/2 hyperactivation. This enhanced migration was abrogated by TGF-β1 as well as low glucose medium and the MEK inhibitor Trametinib. In contrast, high SMAD2 fibroblasts were poorly responsive to TGF-β1, high glucose and Trametinib, exhibiting impaired migration in all conditions. Conclusions: The basal migration advantage of high SMAD3 fibroblasts provides a straightforward mechanism underlying the larger accumulation of TAFs previously reported in ADC compared to SCC. Moreover, our results encourage using MEK inhibitors in ADC-TAFs but not SCC-TAFs.2023http://zaguan.unizar.es/record/12435410.1038/s41416-022-02093-xhttp://zaguan.unizar.es/record/124354oai:zaguan.unizar.es:124354info:eu-repo/grantAgreement/ES/AEI-FEDER/SAF2016-79527-Rinfo:eu-repo/grantAgreement/ES/AEI/AEI PID2019-110944RB-I00info:eu-repo/grantAgreement/ES/FIS FEDER/PS09-02368info:eu-repo/grantAgreement/ES/ISCIII PI14-01109info:eu-repo/grantAgreement/ES/ISCIII PI18-00920info:eu-repo/grantAgreement/ES/MCIU/FPU17-03867info:eu-repo/grantAgreement/ES/MICINN-AEI-FEDER/PID2021-122409OB-C21info:eu-repo/grantAgreement/ES/MICINN/RTI2018-094494-B-C21BRITISH JOURNAL OF CANCER 128 (2023), 967-981byhttp://creativecommons.org/licenses/by/3.0/es/info:eu-repo/semantics/openAccess