Submitted by PPG Biologia Celular e Molecular (bcm@pucrs.br) on 2017-07-24T18:23:29Z No. of bitstreams: 1 RAFAEL_SANGUINETTI_CZEPIELEWSKI_TES.pdf: 5487109 bytes, checksum: 88dbb99b9597e08253e2832cc01ccfce (MD5) / Approved for entry into archive by Caroline Xavier (caroline.xavier@pucrs.br) on 2017-07-25T17:50:46Z (GMT) No. of bitstreams: 1 RAFAEL_SANGUINETTI_CZEPIELEWSKI_TES.pdf: 5487109 bytes, checksum: 88dbb99b9597e08253e2832cc01ccfce (MD5) / Made available in DSpace on 2017-07-25T18:00:09Z (GMT). No. of bitstreams: 1 RAFAEL_SANGUINETTI_CZEPIELEWSKI_TES.pdf: 5487109 bytes, checksum: 88dbb99b9597e08253e2832cc01ccfce (MD5) Previous issue date: 2016-03-18 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / Tumor microenvironment and inflammatory diseases promote alterations in our immune system along with their development. Several molecules are implicated in this modulation and are therefore considered therapeutic targets. Gastrin-releasing peptide (GRP) is produced in tumors where it promotes cellular proliferation. It is also correlated with chronic diseases, as in rheumatoid arthritis and asthma, and in the acute condition of sepsis. Recently, our group found a direct GRP action over neutrophils, promoting migration. This work aimed to study the interface between GRP-producing tumors and the recruitment of immune cells, as well as extend the cellular studies about neutrophil activation and migration processes promoted by the peptide. In tumors, we observed that a lung adenocarcinoma cell line does not proliferate in response to GRP. Yet, it is induced to migrate when exposed to the peptide, indicating a potential role for GRP in metastasis of this type of cancer. In our tumor immunology studies, we established a novel in vivo model by overexpressing GRP in a melanoma cell line (B16F10). We observed the augment of infiltrating inflammatory monocytes in the tumor microenvironment of these tumors. In parallel, we verified that reactive oxygen species production and migration in response to GRP is dependent of the NADPH oxidase complex. GRP stimulation promotes an intense activation, which culminates in neutrophil extracellular traps (NETs) release. In addition, the GRP receptor (GRPR) antagonist RC-3095 presented anti-inflammatory potential, inhibiting neutrophil migration towards IL-8 and reducing the extent of acetaminophen-induced liver damage. This effect was due to motility alterations in infiltrating neutrophils within the tissue and reduction of cell adhesion molecules. The results presented herein demonstrate the wide panorama of GRP?s interactions in tumor and immune biology. / O microambiente tumoral e as doen?as inflamat?rias promovem altera??es nas c?lulas do nosso sistema imune ? medida que progridem. Diversas mol?culas est?o envolvidas nessa modula??o, e por isso s?o alvos terap?uticos. O pept?deo liberador de gastrina (GRP) ? produzido por tumores, onde promove prolifera??o celular. Este tamb?m est? correlacionado com doen?as cr?nicas como a artrite reumatoide e asma, e em doen?as agudas, como a sepse. Recentemente, nosso grupo descobriu a??o direta do GRP em neutr?filos, promovendo indu??o de migra??o. O presente trabalho se prop?s a estudar a interface entre tumores produtores de GRP e o recrutamento celular, assim como aprofundar os estudos celulares sobre os processos de ativa??o e migra??o de neutr?filos promovidos pelo pept?deo. Em tumores, observamos que uma linhagem de adenocarcinoma pulmonar n?o prolifera quando exposto ao GRP, por?m ? induzida a migrar quando exposta ao pept?deo, estabelecendo um potencial papel deste na promo??o de met?stases para esse tipo tumoral. Na interface da imunologia tumoral, atrav?s do desenvolvimento de um modelo in vivo de superexpress?o de GRP em melanoma murino (B16F10), observamos que esse aumento do GRP induz a infiltra??o de mon?citos inflamat?rios no microambiente tumoral. Em paralelo, verificamos que a produ??o de esp?cies reativas de oxig?nio e a migra??o em dire??o ao GRP s?o dependentes do complexo NADPH oxidase. Esse est?mulo promove ativa??o intensa, culminando na produ??o de redes extracelulares de neutr?filos (NETs). J? o antagonista do seu receptor, GRPR, apresentou potencial antiinflamat?rio, sendo capaz de inibir a migra??o neutrof?lica via modula??o de IL-8 e reduzindo a extens?o da les?o hep?tica induzida por paracetamol (acetaminofeno), alterando a motilidade dos neutr?filos no tecido e a express?o de mol?culas de ades?o. Assim, os resultados aqui apresentados demonstram um panorama amplo da fun??o do GRP na biologia tumoral e no sistema imune.