Effect of interferon gamma and tumour necrosis factor alpha on sensitivity to cisplatin in ovarian carcinoma cell lines

Chemoimmunotherapy using pegylated liposomal Doxorubicin and interleukin-18 in recurrent ovarian cancer: a phase I dose-escalation study

Recombinant interleukin (IL)-18 (SB-485232) is an immunostimulatory cytokine, with shown antitumor activity in combination with pegylated liposomal doxorubicin (PLD) in preclinical models. This phase I study evaluated the safety, tolerability, and biologic activity of SB-485232 administered in combination with PLD in subjects with recurrent ovarian cancer. The protocol comprised four cycles of PLD (40 mg/m(2)) on day 1 every 28 days, in combination with SB-485232 at increasing doses (1, 3, 10, 30, and 100 μg/kg) on days 2 and 9 of each cycle, to be administered over five subject cohorts, followed by discretionary PLD monotherapy. Sixteen subjects were enrolled. One subject withdrew due to PLD hypersensitivity. Most subjects (82%) were platinum-resistant or refractory, and had received a median of three or more prior chemotherapy regimens. SB-485232 up to 100 μg/kg with PLD had an acceptable safety profile. Common drug-related adverse events were grade 1 or 2 (no grade 4 or 5 adverse events). Concomitant PLD administration did not attenuate the biologic activity of IL-18, with maximal SB-485232 biologic activity already observed at 3 μg/kg. Ten of 16 enrolled subjects (63%) completed treatment, whereas five (31%) subjects progressed on treatment. A 6% partial objective response rate and a 38% stable disease rate were observed. We provide pilot data suggesting that SB-485232 at the 3 μg/kg dose level in combination with PLD is safe and biologically active. This combination warrants further study in a phase II trial.

Interleukin (IL)-18, a biomarker of human ovarian carcinoma, is predominantly released as biologically inactive precursor

Interleukin (IL)-18 is a proinflammatory and immune-enhancing cytokine, which exerts antitumor effects in vivo, mediated by the induction of interferon (IFN)γ. We previously reported that IL-18 processing is defective in epithelial ovarian carcinoma (EOC) cells, which secrete an inactive precursor (pro-IL-18) in vitro. In addition, IL-18 was reported as a potential biomarker of EOC. Here, we further investigated its role as a serological marker in human EOC and addressed its possible biological activity in vivo. Our data indicate that immunoreactive IL-18 is increased in EOC patients' sera at diagnosis as compared with age-matched healthy women. IL-18 levels were higher in the ascitic fluids than in sera, suggesting a local production in the peritoneal cavity. Indeed, immunohistochemical analysis of tumors showed IL-18 expression in cytokeratine-positive neoplastic cells, although also scattered histiocytes and some lymphoid cells stained for IL-18. The detection of human IL-18 in sera and ascitic fluids of immunodeficient mice, orthotopically implanted with human EOC cells, further suggested that circulating IL-18 is tumor-derived. However, IL-18 is not an EOC specific biomarker, as increased serum levels were found also in some endometrial cancer patients. By means of a new monoclonal antibody, we characterized IL-18 present in the ascitic fluid as pro-IL-18, which is biologically inactive. Accordingly, IFNγ was not increased in EOC patients' sera and ascitic fluids and showed no correlation with IL-18 levels. Altogether these data indicate that IL-18 in EOC fluids is predominantly tumor-derived and that its lack of biological activity may represent a mechanism of tumor-escape.

Interferon-gamma in combination with carboplatin and paclitaxel as a safe and effective first-line treatment option for advanced ovarian cancer: results of a phase I/II study

We have previously shown that interferon-gamma 1b (IFN-gamma) in combination with cyclophosphamide and cisplatin significantly prolongs progression-free survival in ovarian cancer. In this phase I/II study, we examined if administration of IFN-gamma is also safe in combination with the current standard treatment, paclitaxel and carboplatin. Thirty-four patients with newly diagnosed advanced epithelial ovarian cancer, FIGO stage III/IV, were treated for six to nine cycles with paclitaxel (175 mg/m(2)) and carboplatin (area under the curve [AUC] 5) every 3 weeks. IFN-gamma was administered in an escalating dose from 6 days/cycle with 0.025 mg sc up to 9 days/cycle with 0.1 mg sc. As expected, administration of IFN-gamma was associated with flu-like symptoms. Grade 3/4 neutropenia was observed in 74% (25 out of 34) of patients. Other side effects, in particular peripheral neuropathies, were within the previously observed ranges for the paclitaxel plus carboplatin combination. Overall response rate (complete or partial response) in patients who received either six or nine doses (0.1 mg) of IFN-gamma/cycle (n = 28) was 71%. IFN-gamma is safe in combination with carboplatin and paclitaxel for first-line treatment of patients with advanced ovarian cancer. This combination should be further evaluated as an immunotherapeutic treatment option for ovarian cancer.

Augmentation of cisplatin cytotoxicity using cytokines on cervical carcinoma cell lines

We investigated whether the biological response modifiers like IFN-alpha, IFN-gamma and TNF-alpha could enhance the cytotoxic action of cisplatin on cervical carcinoma cell lines in vitro. The sensitivity of three cell lines SiHa, ME 180 and C33A to these agents was tested using colorimetric MTT assay as well as tritiated thymidine uptake. All the three cell lines demonstrated range of sensitivity to cisplatin and cytokines. Interferons and TNF when used in combination with lower dose of cisplatin showed a significant enhancement of cytotoxic action of the drug in all the cell lines. Thus these data indicate that cytokines in concert with the drug may have a potential to improve the 'in vivo' therapy in these patients.

Tumour necrosis factor and interferon are selectively cytostatic in vitro for hormone-dependent and hormone-independent human breast cancer cells

Since experimental studies have shown that tumour necrosis factor-alpha (TNF-alpha) has potent anti-tumour activity that can be potentiated with cytokines, we tested the efficacy of TNF-alpha with interferon-gamma (IFN-gamma) on different human breast cancer cell lines, particularly comparing hormone-dependent and -independent phenotypes. TNF-alpha inhibited the growth of hormone-dependent human MCF-7, ZR-75-1 and T47-D breast cancer cells with a half maximal concentration of 0.25 nM. In contrast, the growth of hormone-independent cells MDA-MB-231 and HS578T was not affected by TNF-alpha alone, but a synergistic inhibition was observed when using IFN-gamma and TNF-alpha together. The mRNA for the proto-oncogene C-MYC, as an intracellular indicator of cell activation, was significantly increased in MCF-7 cells in the presence of TNF-alpha. In MDA-MB-231 cells this mRNA was increased only in the presence of both TNF-alpha and IFN-gamma, without a change in the number of surface TNF receptors. These findings indicate that TNF-alpha treatment in combination with IFN-gamma may provide a successful approach to overcome the cellular heterogeneity of advanced breast tumours.