Direct and indirect effects of recombinant human granulocyte-colony stimulating factor on in vitro colony formation of human bladder cancer cells

Abstract

Although the present experimental use of recombinant human granulocyte-colony-stimulating factor (rG-CSF) has been proven to alleviate the myelosuppression induced by antitumor chemotherapy, it is also believed to stimulate growth of some nonhematopoietic tumor cells. We investigated both the direct and indirect effects of rG-CSF on in vitro colony formation of human bladder cancer cell lines using a modified human tumor clonogenic assay. Peripheral blood mononuclear cells (PBMC) were used as feeder cells (a mixture of 5 x 10(4) monocytes/dish and 5 x 10(5) lymphocytes/dish obtained from healthy donors). Human bladder cancer cell lines KK-47, TCCSUP and T24, all derived from human transitional-cell carcinomas, were incubated continuously with various concentrations of rG-CSF ranging from 0.01 ng/ml to 10 ng/ml both with and without PBMC for 7-21 days. The concentrations of rG-CSF used were chosen as being in the range of achievable serum concentrations in patients treated with rG-CSF. At the end of incubation, colonies were counted under an inverted phase-contrast microscope, and an increase in the number of colonies in comparison with the control was used to evaluate the effects of rG-CSF. Results were expressed as a percentage of controls. rG-CSF in the upper layer at concentrations ranging from 0.1 ng/ml to 10 ng/ml stimulated the colony formation of all the cancer cell lines tested in the absence of PBMC in the feeder layer, whereas cells with PBMC in the feeder layer were significantly stimulated more than those without PBMC in the feeder layer (P < 0.05) up to a certain concentration, which varied from cell line to cell line. At higher concentrations of rG-CSF, no further stimulation but, on the contrary, a decrease in colony formation was observed in cells with PBMC in the feeder layer in all the cell lines tested. Colony formation in KK-47 and T24 cell lines was significantly inhibited at 5 ng/ml and/or 10 ng/ml rG-CSF compared with cells without PBMC in the feeder layer. Our results suggest that rG-CSF may have both direct and indirect stimulatory effects on the growth of human bladder cancer cell lines in vitro. The results obtained also raise the possibility of adverse effects of rG-CSF in bladder cancer patients whose malignant cells may be directly and indirectly stimulated by this factor while it is being used clinically to alleviate the myelosuppression induced by antitumor chemotherapy.

A Case of Uterine Cervical Cancer Presenting with Granulocytosis

“…A variety of nonhematopoietic malignant tumors have been demonstrated to secrete G-CSF1-4), and most of these patients had a poor clinical outcome. A few studies have shown that treatment of bladder cancer cell lines with exogenous G-CSF in vitro results in enhanced tumor growth stimulation11, 12). Therefore, we suggest that these malignant tumors should be regarded as aggressive and advanced disease, as they may have a high probability of poor response to treatment.…”

Grave outcome of granulocyte colony‐stimulating factor‐producing endometrial cancer: A case report and literature review

“…9,10 Previous studies demonstrated that treatment with exogenous G-CSF enhanced the growth of bladder cancer cells in vitro. 9,10 More recently, a paracrine effect of G-CSF has also been reported. Treatment with G-CSF stimulated tumorassociated CD11b + Gr1 + myeloid cells and facilitated tumor angiogenesis in vivo.…”

A Case of Lethal Abdominal Compartment Syndrome due to Rapidly Expanding Ovarian Small Cell Carcinoma Pulmonary Type

“…Evidence by Thacker and colleagues and Shameem and colleagues demonstrates that the presence of G-CSF can stimulate growth in bladder cancer cells and osteosarcoma tumors, and thus autonomous factor production in gynecological malignancies could explain such rapid expansion and leukocytosis [17,18]. Malignant ascites can be seen with ovarian cancers, suspected to be the result of tumor cells producing excessive amounts of ascites while obstructing the lymphatic drainage system.…”