Granulocyte colony-stimulating factor (G-CSF) receptor gene expression of ovarian carcinoma does not correlate with G-CSF caused cell proliferation.

BACKGROUND: Recombinant human granulocyte colony-stimulating factor (rhG-CSF) is a growth factor commonly used to avoid leukopenia after chemotherapy. Endogenous G-CSF is produced by macrophages and granulocytes that infiltrate tumors. It has been reported that rhG-CSF stimulates the proliferation of several cell lines as well as bladder carcinoma cells. Conversely, in some hematopoietic cell lines such as U-937, WEHI-3B, and K-562 no effect or in some cases a differentiation pattern was found. Moreover, the role of rhG-CSF on the proliferation of solid tumors is not well understood. METHODS: In this study, 10 ovarian carcinoma biopsies were characterized for the presence of G-CSF and G-CSF receptor by reverse transcription-polymerase chain reaction (RT-PCR) and immunohistochemical analysis. Proliferation was analyzed by ATP viability assays. RESULTS: Performing RT-PCR, these biopsies and four ovarian carcinoma cell lines were analyzed for endogenous G-CSF production, which was found in some biopsies and in all cell lines. Despite the presence of the G-CSF receptor in all biopsies and cell lines, no proliferation was found after rhG-CSF incubation of the cell lines or the tumor samples for 3 and for 6 days, respectively. CONCLUSIONS: Summarizing the authors' in vitro studies, rhG-CSF does not affect the proliferation of ovarian carcinoma cells in vitro.

Evaluation of methods to detect p53 mutations in ovarian cancer.

OBJECTIVE: The p53 status is increasingly regarded as a marker predictive of response to particular cancer therapies, but for this approach it is self-evident that the p53 status must be determined correctly. METHODS: We have tested ovarian cancers with single-strand conformation polymorphism analysis (SSCP), immunohistochemical staining with DO-1 anti-p53 antibody (IHC), and yeast p53 functional assay (FASAY). RESULTS: These techniques commonly used to detect p53 mutations showed important differences in their sensitivity. Of 53 tumors tested with three indirect techniques, 27 (50%), 33 (62%) and 41 (77%) were positive by SSCP, IHC, and FASAY, respectively. In a subset of 32 tumors strongly suspected of containing mutations, 25 (78%), 26 (81%), 29 (91%) and 30 (94%) were positive by SSCP, immunostaining, DNA sequencing and yeast assay, respectively. CONCLUSIONS: Under comparable routine conditions, the FASAY reached the highest sensitivity. Since no single technique detected all mutations, we recommend the use of at least two different techniques in situations where the p53 status will affect patient management.

G-CSF receptor expression in ovarian cancer.

Recombinant human granulocyte colony-stimulating factor (rhG-CSF) is clinically used to overcome neutropenic periods during chemotherapy. In vitro studies using cell lines as a model system have recently suggested that G-CSF can promote ovarian cancer growth. The objective of this work is to determine whether tumor cells express G-CSF-receptors (G-CSFR). A set of ovarian tumor biopsies and ovarian cancer cell lines was analyzed by RT-PCR, immunohistochemistry and immunofluorescence. The presence of a 276 bp-amplicon (exon 8-10) obtained by RT-PCR showed that 12 out of 16 ovarian tumor biopsies and two out of four ovarian cancer cell lines expressed G-CSFR-mRNA. G-CSFR-protein was detected in tumor cells of the 12 biopsies that also contained G-CSFR-mRNA. A second 409 bp-amplicon (exon 17) obtained by RT-PCR from the variable C-terminal cytoplasmic region of G-CSFR could be amplified only in four out of 16 biopsies and in none of the ovarian cancer cell lines studied. The results presented here indicate that G-CSFR is frequently expressed in ovarian cancer cells. Moreover, the failure of RT-PCR amplification of the 409 bp-amplicon in samples that express G-CSFR-mRNA suggests that C-terminal truncated receptor forms are also expressed.

rhG-CSF affects genes involved in mitogen signalling and early gene expression in the ovarian cancer cell line HEY.

The ovarian adenocarcinoma cell line HEY was used as an in vitro model to study the influence of recombinant human granulocyte colony-stimulating factor (rhG-CSF) on epithelial tumours such as ovarian cancer. Serum-starved cells were treated with rhG-CSF in a time- and dose-dependent manner. Cell proliferation, measured as cell division and DNA synthesis, was stimulated about 40% by rhG-CSF. After harvesting, cells were examined for the presence of G-CSF receptor (FACS analysis and RT-PCR), as well as for expression of genes involved in mitogen signalling (ERKs, JNKs) and early gene expression (c-jun). rhG-CSF affected mitogen-activated pathways and was receptor-mediated if the G-CSF receptor was present. After rhG-CSF induction, Janus N-terminal kinases (JNK 1 and 2) were simultaneously increased in the cytosol, up to 30-fold as measured by Western blotting), whereas ERK 1 and 2 accumulated maximally by 2.5-fold 1 hr after rhG-CSF induction. c-Jun was up-regulated strongly by this cytokine at the translational level. Our data suggest that rhG-CSF affects genes involved in mitogen signalling and early gene expression in solid tumours. We also noted the presence of G-CSF receptor on ovarian cancer cell lines.

Influencia del G-CSF en el crecimiento celular en el adenocarcinoma ovarico / Influence of G-CSP on the proliferation an ovarian adenocarcinoma cell line

El factor de crecimiento hematopoyético G-CSF (factor estimulante de las colonias de granulocitos) es clínicamente usado para superar períodos de neutropenia y para aumentar los niveles endógenos de neutrófilos durante la quimioterapia. Sin embargo poco es lo conocido acerca de los aspectos sobre células tumorales. Por el otro lado, los cánceres de ovario son frecuentemente infiltrados con glóbulos blancos que producen localmente G-CSF, por lo tanto esta cytoquina puede en forma sistémica o parácrina jugar un importante rol en el desarrollo tumoral en tumores que presentan receptores de G-CSF. Las cytoquinas pueden presentar ambos efectos, positivo o negativo, en las células que presentan cancerogénesis, signos incipientes de proliferación, diferenciación o apoptosis. Ellas juegan un rol mayor en la determinación del microambiente tumoral por las interacciones entre el huésped y las células tumorales en los estadios precoces del desarrollo tumoral y el crecimiento celular