Serum interferon alpha receptor 2 mRNA may predict efficacy of interferon alpha with/without low-dose sorafenib for metastatic clear cell renal cell carcinoma.

BACKGROUND: Interferon (IFN) alpha is one of the central agents in immunotherapy for renal cell carcinoma (RCC). It acts by binding to the IFN-alpha receptor (IFNAR). We previously reported that increased tumor expression of IFNAR2 mRNA was associated with the metastatic potential and progression of RCC, as well as with a poor response of metastatic RCC to IFN-alpha therapy. This study investigated the influence of serum IFNAR2 in RCC patients. METHODS: We measured serum IFNAR2 mRNA levels and quantified IFNAR mRNA expression in paired tumor and non-tumor tissues from the surgical specimens of 66 consecutive RCC patients by the real-time reverse transcription polymerase chain reaction (RT-PCR). We also measured phosphorylated Akt (Ser-473) and phosphorylated-S6 ribosomal protein (Ser-235/236) proteins levels in paired tumor and non-tumor tissues of patients with metastatic RCC by Western blotting. RESULTS: The serum level of IFNAR2 mRNA was not associated with its tumor tissue level. Serum IFNAR2 mRNA was positively correlated with tumor size (P < 0.05), but not with tumor grade, pT stage, metastasis, microscopic vascular invasion, or serum C-reactive protein. Serum levels of IFNAR2 mRNA were significantly higher in patients with a good response to IFN-alpha ± sorafenib than in those with a poor response (P < 0.0001). Tumor tissue IFNAR2 mRNA levels and phosphorylated-S6 ribosomal protein (Ser-235/236) levels were associated with metastatic potential (P < 0.001 and P < 0.01, respectively), and patients with a low IFNAR2 mRNA level and low phosphorylated Akt (Ser-473) protein level in the primary tumor showed a good response to IFN-α ± sorafenib (IFN-α ± Sor: CR-PR) (P < 0.01 and P < 0.05, respectively). Kaplan-Meier survival analysis showed that a higher serum IFNAR2 mRNA level was associated with longer overall survival of treated patients (P < 0.05), while a higher tumor tissue IFNAR2 mRNA level was related to shorter overall survival (P < 0.01). CONCLUSIONS: Our findings suggest that a high serum level of IFNAR2 mRNA may be a useful marker for predicting the response of metastatic RCC to IFN-alpha ± sorafenib therapy.

Germline polymorphism of interferon-lambda3 is clinically associated with progression of renal cell carcinoma.

Renal cell carcinoma (RCC) is an immunogenic tumor that shows a metabolic shift to aerobic glycolysis. The immune system can have opposing host-protective and tumor-promoting effects, and aerobic glycolysis suppresses antitumor immunity. In addition to immunostimulatory effect, increasing numbers of studies have revealed that interferon (IFN) is also involved in promoting immunosuppression. Since various single nucleotide polymorphisms (SNPs) can influence the outcome of anticancer therapy, we investigated SNPs for IFN-lambda3, a new member of IFN family, in 53 patients with metastatic RCC who underwent cytoreductive nephrectomy. The 16 patients who were heterozygous/homozygous for the minor alleles of SNPs for IFN-lambda3 had a significantly worse response to sequential vascular endothelial growth factor-targeting therapy (P = 0.0029) and shorter survival (P = 0.0033) compared with the 37 patients possessing the major alleles of SNPs for IFN-lambda3. In these 16 patients, the primary tumor showed elevated glucose uptake on positron emission tomography with [18F] fluorodeoxyglucose (P = 0.0160) and increased expression of programmed cell death 1 (PD-1)-ligand 1 (PD-L1) and phosphorylated serine/threonine kinase Akt (P = 0.0006 and P = 0.0043, respectively) compared to the tumors of the patients without these alleles. Since IFN-induced PD-L1 expression on either tumor cells or tumor-infiltrating mononuclear cells can trigger immunosuppression due to crosstalk between cancer cells and T cells, IFN-lambda3 polymorphism might be linked to the immunosuppressive effects of IFNs in cancer. Although this retrospective study lacks mechanistic insight, our findings suggest that IFN-lambda3 polymorphism might be relevant to the progression of RCC.

Increased interferon alpha receptor 2 mRNA levels is associated with renal cell carcinoma metastasis.

BACKGROUND: Interferon-alpha (IFN-alpha) is one of the central agents in immunotherapy for renal cell carcinoma (RCC) and binds to the IFN-alpha receptor (IFNAR). We investigated the role of IFNAR in RCC. METHODS: We quantified IFNAR mRNA expression in paired tumor and non-tumor samples from the surgical specimens of 103 consecutive patients with RCC using a real-time reverse transcription polymerase chain reaction (RT-PCR), and IFNAR2 protein using Western blotting. RESULTS: The absolute level of IFNAR1 and IFNAR2 mRNAs in tumor and non-tumor tissues did not correlate with the malignant and metastatic profiles. The relative yields of the PCR product from the tumor tissue to that from the corresponding non-tumor tissue (T/N) for the expression of IFNAR mRNAs were calculated. While the T/N ratio of IFNAR1 did not correlate with any factor, a high T/N ratio of IFNAR2 correlated with poor differentiation (P < 0.05), local invasion (P < 0.001), and metastasis (P < 0.0001). By multivariate analysis, a high T/N ratio of IFNAR2 predicted a shortened overall survival in all cases (P < 0.05) and a shorter disease-free survival in those without metastasis (M0; 68 cases, P < 0.05). Impressively, patients with a poorer response to IFN-alpha treatment had a higher IFNAR2 T/N ratio than those who had a good response (P < 0.05). IFNAR2c protein expression was higher in the primary tumors in patients with metastases (M1; 35 cases) compared to those without ( P < 0.0001). CONCLUSION: IFNAR2 is associated with the progression of RCC.

Divergent activities of interferon-alpha subtypes against intracellular hepatitis C virus replication.

BACKGROUNDS: Interferon (IFN)-alpha is represented by several structurally related subtypes that show different antiviral and anti-tumor effects. Here, we analyzed differential effects of IFN-alpha subtypes on intracellular hepatitis C virus (HCV) replication using HCV subgenomic replicon system as a model. METHODS: Huh7 and HeLa cells supporting expression of HCV replicon were treated with various concentrations of five recombinant human IFN-alpha subtypes 1, 2, 5, 8, and 10, and with IFN-alpha con1. The effects of IFNs on various cell-signaling pathways were assayed by using ISRE-, GAS-, AP1-, NF-kappa B-, CRE-, and SRE-luciferase reporter plasmids. RESULTS: Each IFN-alpha subtype suppressed HCV replication in a dose-dependent manner. Among them, IFN-alpha8 was the most effective, while IFN-alpha1 was the least effective with 50% inhibitory concentrations of 0.123IU/ml versus 0.375IU/ml, respectively. These differential effects against HCV replication did not correlate with levels of the IFN-responsive ISRE or GAS reporter activities, nor they did activate the other reporters, AP1, NF-kappa B, CRE and SRE. CONCLUSION: There were divergent effects of IFN-alpha subtypes against HCV replication that may be through JAK-STAT-independent pathways. Exploring further mechanisms of action may elucidate IFN-mediated cellular antiviral mechanisms.

Effects of interferon-alpha subtypes on the TH1/TH2 balance in peripheral blood mononuclear cells from patients with hepatitis virus infection-associated liver disorders.

Interferon-alpha (IFN-alpha) has recently been shown to modulate in vitro T helper (Th) 1-driven responses in the peripheral blood mononuclear cells (PBMC) of patients with hepatitis B virus or C virus infection. In this study, we examined the in vitro effects of IFN-alpha subtypes (IFN-alpha1, -alpha2, -alpha5, -alpha8, and -alpha10) on the Th1/Th2 balance in PBMC obtained from patients with hepatitis virus infection-associated liver disorders and chronic hepatitis (CH), in comparison with the effect on healthy control volunteer PBMC. The Th1-type cell percentages and Th1/Th2 ratios were significantly higher in the PBMC of patients when compared with controls both before and after cultivation in vitro, with the IFN-alpha subtypes. The IFNalpha-5 induced an increase in the Th2-type cell percentages in both control and patient PBMC, resulting in that IFN-alpha5 lowered the Th1/Th2 ratio in patients with CH. Furthermore, statistical analysis revealed that IFN-alpha8 significantly promoted an increase in the Th1/Th2 ratios of PBMC from patients with CH and liver cirrhosis (LC) but not that of PBMC from patients with LC-hepatocellular carcinoma (HCC) and HCC. These findings imply that hepatitis virus infection and its disease status modify the effects of IFN-alpha subtypes on Th1 and Th2 immune balance in patients. Our findings should help to elucidate the mechanisms underlying successful IFN therapy for hepatitis virus infection and prevention of hepatocellular carcinogenesis.

The anti-tumor activities of interferon (IFN)-alpha in chronic myelogenous leukaemia (CML)-derived cell lines depends on the IFN-alpha subtypes.

Here we report on the anti-tumor effects of five interferon (IFN)-alpha subtypes, alpha1, alpha2, alpha5, alpha8, and alpha10 in chronic myelogenous leukaemia (CML)-derived cell lines. All of the CML cells can respond to IFN-alpha although the anti-tumor effects of IFN-alpha depend on the target cell and on the type of IFN-alpha subtype used. Proliferation assays showed that IFN-alpha8 was substantially more effective than the other four IFN-alpha subtypes. IFN-alpha8 was the most potent at upregulating immunomodulatory molecule expression while IFN-alpha1 was least potent. These data indicate in vitro distinctions between IFN-alpha subtypes that should be appreciated more in the clinic.

Expression profiling of tumor necrosis factor alpha-induced apoptosis-associated genes in human solid tumor cell lines.

BACKGROUND: The induction of genes associated with cellular apoptosis by tumor necrosis factor-alpha (TNF-alpha) in human cancer cell line sof various tissue origins may characterize TNF-alpha responder cell lines/cancers. MATERIALS AND METHODS: Using quantitative real-time polymerase chain reaction (PCR), the comprehensive molecular profiling of genes downstream of the TNF-alpha receptor genes in 91 well-defined human cancer cell lines allowed us to elucidate relationships between TNF-alpha response and the genetic expression profiles of the target cell lines. RESULTS: Among the 52 genes tested, the above average expression of Akt mRNA showed significant correlation with TNF-alpha-induced susceptibility to apoptosis. In addition, multidrug resistance protein 5 (MRP5) and tumor necrosis factor receptor type 1 (TNFR1) mRNA expressions also appear to be possible markers for responsiveness to TNF-alpha. CONCLUSION: These results provide a preliminary basis for the screening for genetic markers that may help to predict a favorable therapeutic outcome, and also to identify patients who may benefit from cytokine therapy.

Type 1 interferon receptor in peripheral blood mononuclear cells may predict response to intra-arterial 5-fluorouracil + interferon therapy for advanced hepatocellular carcinoma.

BACKGROUND: Type 1 interferon alpha receptor 2 (IFNAR2) in the liver has been reported to be a predictive factor for the response to intra-arterial 5-fluorouracil (5-FU) + systemic interferon (IFN)-alpha combination therapy in patients with advanced hepatocellular carcinoma. We tested whether IFNAR2 expression in peripheral blood mononuclear cells could predict the response to 5-FU + IFN. METHODS: Predictive factors for survival and response to therapy were determined in 30 patients with advanced hepatocellular carcinoma who underwent treatment with 5-FU + IFN. IFNAR2 expression in peripheral blood mononuclear cells was measured in 11 of the 30 patients. RESULTS: With a mean number of 4.2 courses of combination therapy, one patient (3%) showed a complete response, eight (27%) showed partial responses, 13 (43%) had stable disease, and eight (27%) showed progressive disease. The median survival time of responders (complete response/partial response) was 12.7 months and that of nonresponders (stable disease/progressive disease) was 7.5 months. The one-year and two-year cumulative survival rates of responders and nonresponders were 87/69% and 40/11%, respectively (P = 0.019). Multivariate analysis identified response to therapy (P = 0.037) as the sole independent determinant of survival. The expression level of IFNAR2 in peripheral blood mononuclear cells was significantly (P = 0.012) higher in responders (6.5 ± 2.4) than in nonresponders (2.4 ± 0.6), even though no clinical factors were identified as being associated with the response to the combination therapy. CONCLUSION: IFNAR2 expression in peripheral blood mononuclear cells may predict the response to 5-FU + IFN therapy in patients with advanced hepatocellular carcinoma, although these data are preliminary.

Antitumor effects of a combination of interferon-alpha and sorafenib on human renal carcinoma cell lines.

To support the role of interferon (IFN)-alpha and sorafenib combination therapy against renal cell carcinoma (RCC), the effects of IFN-alpha and sorafenib on tumor growth, vascular endothelial growth factor (VEGF) production, and phosphorylation levels of extracellular signal-regulated kinase (ERK) and mitogen-activated protein/ERK kinase (MEK) were examined using several cultured RCC cell lines (ACHN, Caki-1, Caki-2, SMKT-R1, SMKT-R2, SMKT-R3 and SMKT-R4). IFN-alpha or sorafenib alone inhibited the proliferation of all the cell lines except Caki-2, while combined treatment with the two agents showed enhanced inhibitory effects compared to treatment with each agent alone. VEGF production was inhibited by IFN-alpha alone in ACHN and SMKT-R2 cells and by sorafenib alone in ACHN, Caki-1, SMKT-R1 and SMKT-R2 cells. However, sorafenib increased VEGF production by Caki-2 cells. Interestingly, combined treatment with the two agents suppressed VEGF production by SMKT-R1 and SMKT-R2 cells more strongly than IFN-alpha or sorafenib alone. Although phosphorylated ERK (p-ERK) was increased after 30 min of treatment with IFN-alpha alone, no difference was observed between control and IFN-alpha-treated cells after 2 h. Sorafenib decreased p-ERK in ACHN, Caki-1, SMKT-R1 and SMKT-R2 cells, but increased p-ERK in Caki-2, SMKT-R3 and SMKT-R4 cells, after 2 h. Combined treatment with IFN-alpha and sorafenib decreased p-ERK compared to treatment with each agent alone in all cell lines except Caki-2. However, IFN-alpha did not inhibit the p-ERK increase induced by sorafenib in Caki-2 cells. Phosphorylated MEK showed similar patterns to p-ERK after the various treatments. In conclusion, combined treatment with IFN-alpha and sorafenib suppressed cell proliferation and VEGF production more strongly than treatment with each agent alone in several RCC cell lines.

Interferon-related mental deterioration after craniotomy for removal of metastatic renal cancer.

Interferon-related severe adverse events on the central nervous system are relatively rare, because interferon-alpha (INF-alpha) can not cross an intact blood-brain barrier. We experienced remarkable mental deterioration caused by INF-alpha administration in a 43-year-old man with renal cell carcinoma after surgical removal of a metastatic brain tumor. We detected a high concentration of INF-alpha in a cerebrospinal fluid sample, which was comparable to that in the serum at 24 h after the administration of INF-alpha; 5x10(6) IU i.m., suggesting that the blood-brain barrier was damaged somehow by the craniotomy. The mental deterioration improved shortly after discontinuation of the INF-alpha administration.

Growth inhibitory effects of interferon-alpha subtypes vary according to human liver cancer cell lines.

BACKGROUND: Interferon (IFN)-alpha preparations used in the treatment of viral and neoplastic disease consist of single or multiple IFN-alpha subtypes that may possess different biological activity, but there are no data on liver cancer cells. METHODS: Antiproliferative effects and the mechanisms of growth inhibition of five IFN-alpha subtypes (alpha1, alpha2, alpha5, alpha8 and alpha10) were examined in vitro using 13 human liver cancer cell lines. RESULTS: The antiproliferative effect of each IFN-alpha subtype was different in each cell line. The 50% growth inhibitory concentration (IC50) on an antiviral unit basis showed that alpha5 presented the most potent antiproliferative effects in 11 of the 13 cell lines, and alpha8 in two cell lines. On average, the antiproliferative effects were strong in descending order from alpha5, alpha8, alpha10, alpha2 to alpha1. On weight basis, the most potent antiproliferative effect was shown by alpha8 in nine of the 13 cell lines, alpha5 in four cell lines, and the potency of the effects on average in descending order was alpha8, alpha5, alpha10, alpha2 and alpha1. No significant difference was observed between natural and recombinant alpha2. The mechanism of growth inhibition of each subtype in HAK-1B and KMCH-1 cell lines were apoptosis and S-phase arrest, and their induction levels were related to a certain degree to the antiproliferative effects. CONCLUSIONS: Our findings show that the antiproliferative effect of each IFN-alpha subtype varies according to the cell line, but that the cells are relatively or absolutely responsive to alpha5 and alpha8 subtypes.

Correlation Between Interferon Alpha Receptor Protein Expression and Sensitivity to Interferon Alpha Subtypes in Human Renal Carcinoma Cell Lines.

BACKGROUND: We have previously characterized the antitumor activities and immunological properties of interferon-alpha (IFN-α) subtypes on renal cell carcinoma (RCC). However, the mechanism responsible for the different biologic activities among the IFN-α subtypes is still unclear. To explain the different cellular sensitivities to IFN-α subtypes, detailed expression of the interferon-alpha receptor (IFNAR)-1 and IFNAR-2 subunits on different RCC cell lines was examined and compared with sensitivity of the cell lines to the IFN-α subtypes. MATERIALS AND METHODS: We investigated the antiproliferative effects of natural IFN-α subtypes (IFN-α2 and IFN-α8) using eight RCC cell lines. IFNAR-1 and IFNAR-2 expression were determined by RT-PCR and Western blotting. To determine a possible relationship between IFN activity and IFNAR expression, the correlation between the 50% effective IFN dose (ED50) for growth inhibition and the level of IFNAR expression was statistically examined. RESULTS: We report here that IFN-α8 more potently induced growth inhibition than IFN-α2 in the majority of the RCC cell lines examined, this being in accordance with our previous results. The ED50 value of IFN-α8 was lower than 1000 (IU/ml) in six of the eight cell lines, whereas that of IFN-α2 was lower than 1000 (IU/ml) in three of the eight cell lines. The results of experiments using Western blotting analysis revealed that IFN-α subtype sensitivities were closely correlated with the expression level of IFNAR-2(c), a long form of the IFNAR-2 protein, in seven of the eight cell lines. CONCLUSION: These results suggest that the intensity of IFNAR-2(c) protein expression could be an important prognostic marker for clinical application of particular IFN-α subtypes in RCC.