Functional and genomic characterization of three novel cell lines derived from a metastatic gallbladder cancer tumor

BACKGROUND: Gallbladder cancer (GBC) is the most common tumor of the biliary tract. The incidence of GBC shows a large geographic variability, being particularly frequent in Native American populations. In Chile, GBC represents the second cause of cancer-related death among women. We describe here the establishment of three novel cell lines derived from the ascitic fluid of a Chilean GBC patient, who presented 46% European, 36% Mapuche, 12% Aymara and 6% African ancestry. RESULTS: After immunocytochemical staining of the primary cell culture, we isolated and comprehensively characterized three independent clones (PUC-GBC1, PUC-GBC2 and PUC-GBC3) by short tandem repeat DNA profiling and RNA sequencing as well as karyotype, doubling time, chemosensitivity, in vitro migration capability and in vivo tumorigenicity assay. Primary culture cells showed high expression of CK7, CK19, CA 19-9, MUC1 and MUC16, and negative expression of mesothelial markers. The three isolated clones displayed an epithelial phenotype and an abnormal structure and number of chromosomes. RNA sequencing confirmed the increased expression of cytokeratin and mucin genes, and also of TP53 and ERBB2 with some differences among the three cells lines, and revealed a novel exonic mutation in NF1. The PUC-GBC3 clone was the most aggressive according to histopathological features and the tumorigenic capacity in NSG mice. CONCLUSIONS: The first cell lines established from a Chilean GBC patient represent a new model for studying GBC in patients of Native American descent.

Effects of c-FLIPL knockdown in cervical uterine carcinoma cell lines / Efectos de la inhibición de C-Flipl en líneas celulares de cáncer de cuello uterino

Overexpression of Short and Raji variants of Cellular FLICE-like inhibitory protein (c-FLIP) is capable of inhibiting apoptosis, while the function of the Long isoform depends of c-FLIPL concentration in cells. The aim of this study was to determine the effects of c-FLIPL knockdown in cervical cell lines. SiHa, C-4I and C-33A cervical cancer cell lines were analyzed. c-FLIPL level expression was determined by quantitative real-time PCR and western blotting. c-FLIPL was transiently downregulated by siRNA. The effects of knockdown of c-FLIPL on cell viability, proliferation and apoptosis were assessed by comparing with scrambled siRNA-transfected cells. SiHa and C-4I c-FLIPL knockdown cells showed increased viability compared with scrambled siRNA-transfected cells (P<0.05), while C-33A cells did not show significant differences. Ki-67 and PCNA immunocytochemistry was performed to evaluate proliferation on these cervical cancer cell lines. SiHa cells with c-FLIPL knockdown showed elevated expression of Ki-67 protein compared with their scrambled counterparts (P<0.0001), while C-33A c-FLIPL knockdown cells showed a significantly lower in PCNA expression (P<0.01) compared with control. All three c-FLIP-transfected cell lines showed a higher level of apoptosis compared with their scrambled controls. Our results suggest that c-FLIPL could have effects in proliferation and apoptosis in cervical cancer cell lines.

Cuando las variantes Short y Raji de la proteína Cellular FLICE-like inhibitory protein (c-FLIP) se encuentran sobrexpresadas son capaces de inhibir la apoptosis, mientras la función de la isoforma Long (c-FLIPL), depende de la concentración de esta molécula en las células. El objetivo de este estudio fue determinar los efectos de la inhibición de c-FLIPL en líneas celulares de cáncer de cuello uterino. Para realizar el estudio fueron utilizadas SiHa, C-4I y C-33A, líneas celulares de cáncer cervical. La expresión de c-FLIPL en estas líneas fue establecida mediante PCR en tiempo real y western blot. Posteriormente la expresión de c-FLIPL fue inhibida, mediante transfeción transiente con siRNA complementario al mRNA mensajero de c.-FLIPL. Los efectos de esta inhibición en la viabilidad celular, proliferación y apoptosis fue comparada con células transfectadas con un siRNA control (scrambled). Una vez reprimido c-FLIPL, las líneas celulares SiHa y C-4I presentaron un aumento de la viabilidad celular (P<0,05). Para evaluar la proliferación celular se utilizó inmunocitoquímica de los marcadores Ki-67 y PCNA. Las células SiHa transfectadas con siRNA c-FLIPL, mostraron una elevada expresión de Ki-67 (P<0,0001), mientras que las células C-33A con c-FLIPL inhibido mostraron una menor expresión de PCNA (P<0,01). Las tres líneas celulares con c-FLIPL reprimido mostraron un mayor nivel de apoptosis que las células control. Estos resultados sugieren que c-FLIPL puede tener efectos en la proliferación y apoptosis de líneas celulares de cáncer de cuello uterino.