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

Role of the interleukin 6 receptor family in epithelial ovarian cancer and its clinical implications

Ovarian cancer is the most lethal gynecological malignancy, with few effective treatment options in most cases. Therefore, understanding the biology of ovarian cancer remains an important area of research in order to improve clinical outcomes. Cytokine receptor signaling through the Janus kinase-signal transducer and activator of transcription (JAK-STAT) pathway is an essential component of normal development and homeostasis. However, numerous studies have implicated perturbation of this pathway in a range of cancers. In particular, members of the IL-6R family acting via the downstream STAT3 transcription factor play an important role in a number of solid tumors - including ovarian cancer - by altering the expression of target genes that impact on key phenotypes. This has led to the development of specific inhibitors of this pathway which are being used in combination with standard chemotherapeutic agents. This review focuses on the role of IL-6R family members in the etiology of epithelial ovarian cancer, and the application of therapies specifically targeting IL-6R signaling in this disease setting.

Granulocyte colony-stimulating factor receptor signalling via Janus kinase 2/signal transducer and activator of transcription 3 in ovarian cancer

Background:

Ovarian cancer remains a major cause of cancer mortality in women, with only limited understanding of disease aetiology at the molecular level. Granulocyte colony-stimulating factor (G-CSF) is a key regulator of both normal and emergency haematopoiesis, and is used clinically to aid haematopoietic recovery following ablative therapies for a variety of solid tumours including ovarian cancer.

Methods:

The expression of G-CSF and its receptor, G-CSFR, was examined in primary ovarian cancer samples and a panel of ovarian cancer cell lines, and the effects of G-CSF treatment on proliferation, migration and survival were determined.

Results:

G-CSFR was predominantly expressed in high-grade serous ovarian epithelial tumour samples and a subset of ovarian cancer cell lines. Stimulation of G-CSFR-expressing ovarian epithelial cancer cells with G-CSF led to increased migration and survival, including against chemotherapy-induced apoptosis. The effects of G-CSF were mediated by signalling via the downstream JAK2/STAT3 pathway.

Conclusion:

This study suggests that G-CSF has the potential to impact on ovarian cancer pathogenesis, and that G-CSFR expression status should be considered in determining appropriate therapy.

The effect of G-CSF on F-actin reorganization in HL-60 and K562 cell lines

The aim of this investigation was to show the influence of G-CSF (G-CSF) on the F-actin cytoskeleton and the morphology of G-CSFR-proficient HL-60 and G-CSFR-deficient K562 cell lines. In the present study, we show changes in F-actin distribution in HL-60 cells after treatment with 5 and 10 ng/ml concentration of G-CSF but also changes in the organization and fluorescence intensity of F-actin in the K562 cell line. After treatment of HL-60 cells with 5 ng/ml concentration of G-CSF we observed an increase in F-actin levels. Additionally, a higher labeling of nuclear F-actin under TEM was observed. Moreover, changes in the cell cycle indicate cell differentiation. On the other hand, in the K562 cell line we observed an increase in the percentage sub-G1 cells following treatment with both concentration of G-CSF. Furthermore, an increase in the percentage of late apoptotic cells after G-CSF treatment was observed. A statistically significant difference in the cytoplasmic F-actin levels was not detected, but nuclear levels were decreased. In conclusion, we suggest that the G-CSF-based reorganization of actin filaments in HL-60 cells is involved in the differentiation process. Moreover, we suggest that the G-CSF-induced changes observed in K562 cells are associated with a G-CSF receptor-independent pathway or its binding to other similar receptors.

Synergistic effect of SCF and G-CSF on stem-like properties in prostate cancer cell lines

Bone marrow metastases are formed in the late phases of prostate cancer disease. Stem cell factor (SCF) and granulocyte colony-stimulating factor (G-CSF) are present in the microenvironment of the bone marrow and play a vital role in cell biology therein. The present study was to investigate the influence of SCF and G-CSF on stem-like properties in prostate cancer cell lines. Upon stimulation with SCF or G-CSF, higher levels of CD117, ABCG2, and CD44 were observed in PC-3 and DU145 cells examined by flow cytometry. Simultaneously, the expressions of Oct3/4 and Nanog were upregulated. Moreover, quantitative real-time PCR verified that the increased Nanog under the stimulations was mostly derived from NANOGP8. In parallel with the increasing expressions of these proteins, higher colony and sphere formation efficiencies were seen in these cells in response to the cytokine stimulations. Furthermore, a synergistic effect of SCF and G-CSF on colony and sphere formations and ABCG2 expression was disclosed. Our results indicate a favorable bone marrow niche for prostate cancer cells where higher levels of cell stemness are maintained at least partly by the cytokines SCF and G-CSF.

Combination therapy with sorafenib and S-1 for renal cell carcinoma producing granulocyte colony-stimulating factor

We present the first case report of the use of sorafenib and S-1 for the treatment of renal cell carcinoma (RCC) producing granulocyte colony-stimulating factor (G-CSF). This entity is clinically rare and has a poor outcome. A 78-year-old Japanese man presented with macrohematuria, left flank pain, and a palpable mass. Laboratory data showed marked leukocytosis with increased serum and urinary G-CSF. The histopathological diagnosis was unclassified RCC. New combination therapy with sorafenib and S-1 exerted a therapeutic effect and apparently decreased serum and urinary G-CSF levels, although the patient died of gastrointestinal perforation. The use of combined sorafenib and S-1 may be worthy of consideration in the treatment of RCC producing G-CSF.

Granulocyte Colony-stimulating Factor Suppresses Autologous Tumor Killing Activity of the Peripheral Blood Lymphocytes in the Patients with Ovarian Carcinoma

PROBLEM

Granulocyte colony-stimulating factor (G-CSF) is often administered to patients with chemotherapy-induced leukocytopenia. However, adequate attention has not been paid to its effects on cancer immunology. Reported by us and others, G-CSF often induces immunosuppression and down-regulation of response T helper (Th)2 directed immune reaction both in vivo and in vitro. In this study, we analyzed the effects of G-CSF on interferon (IFN)-gamma production and autologous tumor killing (ATK) activities of peripheral blood mononuclear cells (PBMCs).

METHODS OF STUDY

In order to evaluate the cytokine-induced activation of peripheral T and natural killer (NK) cells, we analyzed IFN-gamma production by interleukin (IL)-2- and IL-12-stimulated PBMCs, using the ELISPOT assay. Specific killing of autologous tumor cells was evaluated by lactate dehydrogenase (LDH) release assay.

RESULTS

The PBMC collected from both cancer-bearing patients and healthy subjects showed IL-2- and/or IL-12-induced IFN-gamma production. The frequency of IFN-gamma producing cells was significantly higher in the normal subjects compared with the patients with advanced ovarian carcinoma. The ATK activity was also enhanced in IL-2- and/or IL-12-stimulated PBMCs of patients with ovarian carcinoma. G-CSF almost completely abolished IFN-gamma production and ATK activity of PBMC stimulated with IL-2 and/or IL-12.

CONCLUSIONS

The G-CSF appears to be a suppressor of antitumor immunity. Routine administration of G-CSF to cancer patients may not be recommended, except for febrile neutropenia.

Granulocyte colony-stimulating factor may promote proliferation of human bladder cancer cells mediated by basic fibroblast growth factor

OBJECTIVES

To investigate whether granulocyte colony-stimulating factor (G-CSF) promotes the proliferation of two bladder cancer cell lines, and to assess the mechanism of tumor proliferation in terms of cytokine expression.

MATERIAL AND METHODS

The proliferation of two bladder cancer cell lines derived from transitional cell carcinoma (KK-47 and T-24) was assessed by using the double-layer soft agarose colony assay in combination with the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Seven cytokines were measured in the culture supernatant. Expression of granulocyte colony-stimulating factor (G-CSF) receptor and fibroblast growth factor (FGF) receptor mRNA was studied by means of reverse transcriptase polymerase chain reaction (RT-PCR).

RESULTS

Recombinant human G-CSF (rhG-CSF) caused greater induction of the proliferation of KK-47 cells in the presence than in the absence of peripheral blood mononuclear cells (PBMCs) and its effect was dose-dependent. In contrast, rhG-CSF did not stimulate the proliferation of T-24 cells. Among several cytokines measured, only basic FGF was elevated in cultures of KK-47 cells with or without PBMCs. The basic FGF level was significantly increased by rhG-CSF stimulation in a dose-dependent manner. Specific PCR products for the G-CSF and FGF receptors were observed in KK-47 cells as well as PBMC, while no G-CSF receptor was detected in T-24 cells.

CONCLUSION

rhG-CSF may promote the proliferation of KK-47 cells, probably via an increase in basic FGF production.

Granulocyte colony stimulation factor (G-CSF) suppresses interleukin (IL)-12 and/or IL-2 induced interferon (IFN)-γproduction and cytotoxicity of decidual mononuclear cells

PROBLEM

The placenta is one of the few non-hematopoietic tissues to express granulocyte colony stimulation factor (G-CSF). Placental G-CSF production is considered to be one of the major causes of granulocytosis during pregnancy although its physiological role in pregnancy has not yet been examined.

METHOD OF STUDY

The effects of G-CSF on interleukin (IL)-2 and/or IL-12 induced interferon (IFN)-gamma production of magnetic cell sorting (MACS) sorted decidual lymphocytes was examined by enzyme-linked immunosorbent spot-forming cell assay (ELISPOT). The effect of G-CSF on cytotoxicity of decidual lymphocytes against the choriocarcinoma cell line JEG-3 was examined by lactate dehydrogenase (LDH) release assay.

RESULTS

As previously reported by us, IL-2 and/or IL-12 activated decidual mononuclear cells were capable of killing choriocarcinoma cells. We observed that G-CSF abolished IFN-gamma production and cytotoxicity of decidual mononuclear cells and MACS sorted CD56+ cells.

CONCLUSIONS

In addition to its well-known trophic effects on hematopoiesis, our results suggest about new roles of G-CSF in reproductive immunology.