Low-dose gamma-interferon therapy is ineffective in renal cell carcinoma patients with large tumour burden

The Safety and Anti-Tumor Effects of Ozonated Water in Vivo

Ozonated water is easier to handle than ozone gas. However, there have been no previous reports on the biological effects of ozonated water. We conducted a study on the safety of ozonated water and its anti-tumor effects using a tumor-bearing mouse model and normal controls. Local administration of ozonated water (208 mM) was not associated with any detrimental effects in normal tissues. On the other hand, local administration of ozonated water (20.8, 41.6, 104, or 208 mM) directly into the tumor tissue induced necrosis and inhibited proliferation of tumor cells. There was no significant difference in the number of terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick-end labeling (TUNEL)-positive cells following administration of ozonated water. The size of the necrotic areas was dependent on the concentration of ozonated water. These results indicate that ozonated water does not affect normal tissue and damages only the tumor tissue by selectively inducing necrosis. There is a possibility that it exerts through the production of reaction oxygen species (ROS). In addition, the induction of necrosis rather than apoptosis is very useful in tumor immunity. Based on these results, we believe that administration of ozonated water is a safe and potentially simple adjunct or alternative to existing antineoplastic treatments.

IFN-γ Protects Cerulein-Induced Acute Pancreatitis by Repressing NF-κB Activation

We explored the pathophysiological roles of IFN-gamma in cerulein-induced acute pancreatitis. In wild-type (WT) mice, cerulein injection caused acute pancreatitis as evidenced by increased serum amylase levels and pathological changes such as interstitial edema, vacuolization, acinar cell necrosis, and neutrophil infiltration in pancreas. Concomitantly, cerulein treatment augmented intrapancreatic gene expression of TNF-alpha, KC/CXCL1, MIP-2/CXCL2, cyclooxygenase-2 (COX-2), and IFN-gamma in WT mice. In situ hybridization combined with immunofluorescence analyses demonstrated that infiltrating neutrophils expressed IFN-gamma mRNA. Unexpectedly, IFN-gamma(-/-) mice exhibited exacerbated cerulein-induced pancreatic injury, with enhanced neutrophil recruitment. Moreover, intrapancreatic gene expression of TNF-alpha, KC/CXCL1, MIP-2/CXCL2, and COX-2 were significantly exaggerated in IFN-gamma(-/-) mice, compared with WT mice. Cerulein activated NF-kappaB, an indispensable transcription factor for gene transcription of TNF-alpha, KC/CXCL1, MIP-2/CXCL2, and COX-2, in pancreas of cerulein-treated WT mice as evidenced by the increases in nuclear amount and DNA-binding activity of NF-kappaB p65. In comparison with WT mice, IFN-gamma(-/-) mice exhibited exaggerated and prolonged NF-kappaB activation, probably due to reduced acetylation of Stat1, a main signal transducer of IFN-gamma, because acetylated Stat1 can inhibit NF-kappaB activation. Indeed, IFN-gamma acetylated Stat1 and reciprocally reduced NF-kappaB activation and COX-2 expression in neutrophils. Finally, even when administered 4 h after the first cerulein injection, IFN-gamma remarkably attenuated acute pancreatitis in both WT and IFN-gamma(-/-) mice, with reduced NF-kappaB activation and COX-2 expression. Thus, IFN-gamma can have anti-inflammatory effects on acute pancreatitis by depressing the proinflammatory consequences of NF-kappaB activation.

Lymphocyte subsets as prognostic markers for cancer patients receiving immunomodulative therapy

Immunogenic features of some malignancies have aroused interest in immunotherapy of cancer. Immunotherapy seems most effective in patients with a small tumour burden, and the focus of immunotherapy trials has, thus, lately been on adjuvant treatment. To enable further development of immunotherapy we need to know more about the mechanisms involved in host defence, especially when the system is influenced by extrinsic factors, that is, immunomodulative agents. T lymphocytes play an important role in the host defence against tumour cells trying to escape from immune surveillance. The mechanisms that regulate the host defence systems are complex, and the influence of extrinsic factors such as immunotherapeutic agents is poorly understood. Most data on lymphocyte subsets in malignant disease originate from melanoma or renal cell carcinoma (RCC) studies, although there are scattered data on lymphocyte subsets also in other malignancies. There are several studies implying that the relative amount of CD4+, CD8+, and natural killer (NK) cells may be important and that, by reducing the tumour burden or by using different therapeutic agents, we can stimulate the host defence. However, only some of these studies imply that these changes can have an impact on clinical outcome and prognosis. The findings of the studies reviewed in this paper are mostly encouraging, but whether the lymphocyte subsets have any value as prognostic markers in patients with malignancies receiving immunotherapy is still unclear. Large randomized immunotherapy trials including an observation arm give an ideal opportunity to recognize those immunological changes that are due to therapy, related to the natural host defence, or whether they have any prognostic value.

Preliminary results of the alternating administration of natural interferon-alpha and recombinant interferon-gamma for metastatic renal cell carcinoma

OBJECTIVE

To evaluate the efficacy and toxicity of the alternating administration of natural (n) interferon (IFN)-alpha and recombinant (r) IFN-gamma for metastatic RCC.

PATIENTS AND METHODS

The study comprised 24 patients (median age 60 years, range 42-77), 20 of whom were evaluable for response and all 24 evaluable for toxicity. Initially, nIFN-alpha was administered subcutaneously on days 1 and 3, and rIFN-gamma on day 2, for 1-2 weeks in the evening or at night, both at doses of 3 MU. If this regimen was tolerated, nIFN-alpha and rIFN-gamma were administered at the same doses on days 1, 3 and 5, and on days 2 and 4, respectively.

RESULTS

There were three complete remissions and two partial remissions, giving a total response rate of 25%. All responders (complete plus partial remission) had undergone nephrectomy. Multiple lung metastases completely disappeared from four responders. The median and maximum time to remission in the responders were 2 and 7 months, respectively. The survival time of the responders was significantly longer than that of those not responding (stable and progressive disease, P=0.0202). Toxicities were mostly limited to WHO grades 1 and 2, with grade 3 leucopenia and grade 4 hepatic dysfunction in only one patient each. These toxicities were transient and there were no treatment-related deaths.

CONCLUSION

The alternating administration of nIFN-alpha and rIFN-gamma is an effective treatment for metastatic RCC. This treatment is particularly suitable for patients who have undergone nephrectomy and have lung metastases.

Phase I-II study of gamma interferon and 5-fluorouracil for patients with metastatic renal cell carcinoma

We have completed a phase I/II trial to evaluate the toxicity and efficacy of the combination of gamma interferon and 5-fluorouracil in metastatic renal cell carcinoma. Gamma interferon was administered at a weekly dose of 100 micrograms. 5-fluorouracil was given as a 5 day continuous infusion days 1-5 of each 21 day cycle. In the phase I portion of the trial, the gamma interferon dose was held constant, while the 5-fluorouracil was escalated from 500 to 800 mg/m2/day. Serum neopterin and beta 2 microglobulin were measured prior to and 48 hours after each dose of gamma interferon for the first six weeks of treatment. Dose limiting toxicity was not encountered in the phase I part of the trial; therefore the phase II study was initiated at the 800 mg/m2/day dose of 5-fluorouracil. No responses were seen among 34 patients treated on the phase II trial. Forty-six percent of patients experienced disease stabilization and the remainder progressed through treatment. In the phase I trial, increments in neopterin and beta 2 microglobulin levels differed significantly between patients treated with lower and higher doses of 5-fluorouracil. We conclude that the addition of 5-fluorouracil to gamma interferon does not appear to enhance the cytokines clinical activity. Incremental increases in macrophage activation markers with escalating 5-fluorouracil doses suggests a role for 5-fluorouracil beyond its usual proposed cytotoxic activity and warrants further investigation into potential immunologic effects of this drug.

Interferon gamma induces cell cycle arrest and apoptosis in a model of ovarian cancer: enhancement of effect by batimastat

Locoregional human IFN-gamma may have activity against refractory ovarian cancer. We investigated this further in an ovarian cancer xenograft model. Administered at clinically relevant doses, intraperitoneal IFN-gamma prolonged the survival of mice bearing multiple established peritoneal tumours, with optimal treatment giving a 3-6-fold increase in median survival time. Daily dosing, which was superior to intermittent treatment, decreased DNA synthesis and induced apoptosis in tumour cells with maximal effects after 7-21 days treatment. This was preceded by an increase in p53 protein at 48 h. The effect of IFN-gamma was not enhanced by sequential treatment with carboplatin. However, the matrix metalloprotease inhibitor, batimastat, further increased mouse survival when given after IFN-gamma. Thus IFN-gamma is cytotoxic to ovarian epithelial cells in vivo and intensive locoregional dosing over short periods is effective. Sequential administration of novel agents that perturb the host/tumour relationship may be of benefit.

Can the CD4+/CD8+ ratio predict the outcome of interferon-alpha therapy for renal cell carcinoma?

BACKGROUND

In a randomised trial, patients with renal cell carcinoma (RCC) treated with vinblastine alone or in combination with interferon-alpha (IFN) were monitored for peripheral blood lymphocyte subsets (CD4+ and CD8+) prior to and during treatment to elucidate the influence of IFN on these cells, and the association of the change in the CD4+/CD8+ ratio with treatment outcome.

PATIENTS AND METHODS

Blood samples were systematically obtained from 30 patients receiving either vinblastine or vinblastine + IFN-alpha-2a. Flow cytometry was used to detect CD4+ (T-helper) and CD8+ cells (T-suppressor) with monoclonal antibodies.

RESULTS

Increasing CD4+/CD8+ ratios were seen in 10 of 17 patients in the vinblastine-IFN group and in 7 of 13 patients in the vinblastine group. Two of three patients achieving a complete response with the vinblastine-IFN treatment showed a dramatic increase in CD4+/CD8+ ratio concomitantly with regression of all metastases. Those treated with vinblastine-IFN who showed an increasing ratio had a better median survival (not reached at 28 months of follow-up) compared to those with a decreasing ratio (6.3-month survival) (P = 0.0037, log-rank). No such difference occurred in patients treated with vinblastine alone. In the multivariate analysis, the increase in CD4+/CD8+ ratio was the most important prognostic factor.

CONCLUSION

In a proportion of patients receiving an interferon-based therapy, IFN seems to influence the host's immune system, resulting in an increased CD4+/CD8+ ratio concomitantly with tumour regression. Changes in the CD4+/CD8+ ratio of patients with metastatic RCC receiving such therapy, may provide valuable prognostic information and a basis for future improvements of immunotherapy.