Immunological and Functional Characterization of RhoGDI3 and Its Molecular Targets RhoG and RhoB in Human Pancreatic Cancerous and Normal Cells.
RhoGDI proteins have been implicated in several human cancers; changes in their expression levels have shown pro- or anti-tumorigenic effects. Pancreatic Ductal Adenocarcinoma (PDAC) is a complex pathology, with poor prognosis, and most patients die shortly after diagnosis. Efforts have been focused on understanding the role of RhoGDI's in PDAC, specially, RhoGDI1 and RhoGDI2. However, the role of RhoGDI3 has not been studied in relation to cancer or to PDAC. Here, we characterized the expression and functionality of RhoGDI3 and its target GTPases, RhoG and RhoB in pancreatic cell lines from both normal pancreatic tissue and tissue in late stages of PDAC, and compared them to human biopsies. Through immunofluorescences, pulldown assays and subcellular fractionation, we found a reduction in RhoGDI3 expression in the late stages of PDAC, and this reduction correlates with tumor progression and aggressiveness. Despite the reduction in the expression of RhoGDI3 in PDAC, we found that RhoB was underexpressed while RhoG was overexpressed, suggesting that cancerous cells preserve their capacity to activate this pathway, thus these cells may be more eager to response to the stimuli needed to proliferate and become invasive unlike normal cells. Surprisingly, we found nuclear localization of RhoGDI3 in non-cancerous pancreatic cell line and normal pancreatic tissue biopsies, which could open the possibility of novel nuclear functions for this protein, impacting gene expression regulation and cellular homeostasis.
Departamento de Biomedicina Molecular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Avenida Instituto Politécnico Nacional 2508, col. San Pedro Zacatenco, C.P. 07360, Mexico City, Mexico.
Mercedes Piedad
MP
de León-Bautista
Departamento de Fisiología, Facultad de Medicina, Universidad Nacional Autónoma de México, Avenida Universidad 3000, Col. Copilco Universidad, Delegación Coyoacán, C.P. 04510, Mexico City, Mexico.
Maria Del Carmen
MD
Cardenas-Aguayo
Departamento de Biomedicina Molecular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Avenida Instituto Politécnico Nacional 2508, col. San Pedro Zacatenco, C.P. 07360, Mexico City, Mexico.
Diana
D
Casique-Aguirre
Facultad de Bioquímica, Instituto Tecnológico de Milpa Alta, Independencia Sur 36, San Salvador Cuauhtenco, Milpa Alta, 12300, Mexico City, Mexico.
Manuel
M
Almaraz-Salinas
Departamento de Anatomía Patológica, Hospital General Doctor Manuel Gea González, Av. Calzada de Tlalpan 4800, Tlalpan, Sección XVI, 14080, Mexico City, Mexico.
Sara
S
Parraguirre-Martinez
Departamento de Biología Molecular e Histocompatibilidad, Hospital Doctor Manuel Gea González, Av. Calzada de Tlalpan 4800, Tlalpan, Sección XVI, 14080, Mexico City, Mexico.
Angelica
A
Olivo-Diaz
Investigación Biomédica y Traslacional, Laboratorio de Medicina Genómica, Hospital 1° de Octubre, ISSSTE, Av. Instituto Politécnico Nacional No. 1669, Colonia: Magdalena de las Salinas, Delegación: Gustavo A Madero, 07760, Mexico City, Mexico.
María Del Rocío
MD
Thompson-Bonilla
Departamento de Biomedicina Molecular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Avenida Instituto Politécnico Nacional 2508, col. San Pedro Zacatenco, C.P. 07360, Mexico City, Mexico.
Miguel
http://orcid.org/0000-0002-3031-9798
M
Vargas
D021441:Carcinoma, Pancreatic Ductal / Q000473:pathology*; D045744:Cell Line, Tumor; D004789:Enzyme Activation; D005455:Fluorescent Antibody Technique; D006801:Humans; D010183:Pancreatic Ducts / Q000473:pathology*; D010190:Pancreatic Neoplasms / Q000473:pathology*; D020741:rho GTP-Binding Proteins / Q000032:analysis / Q000378:metabolism*; D062950:rho Guanine Nucleotide Dissociation Inhibitor gamma / Q000032:analysis / Q000378:metabolism*; D020743:rhoB GTP-Binding Protein / Q000032:analysis / Q000378:metabolism*
D062950:rho Guanine Nucleotide Dissociation Inhibitor gamma; C075397:RHOG protein, human; D020741:rho GTP-Binding Proteins; D020743:rhoB GTP-Binding Protein