Engineering cytokines for cancer immunotherapy: a systematic review

Cytokines are pivotal mediators of cell communication in the tumor microenvironment. Multiple cytokines are involved in the host antitumor response, but the production and function of these cytokines are usually dysregulated during malignant tumor progression. Considering their clinical potential and the early successful use of cytokines in cancer immunotherapy, such as interferon alpha-2b (IFNα-2b; IntronA^®) and IL-2 (Proleukin^®), cytokine-based therapeutics have been extensively evaluated in many follow-up clinical trials. Following these initial breakthroughs, however, clinical translation of these natural messenger molecules has been greatly limited owing to their high-degree pleiotropic features and complex biological properties in many cell types. These characteristics, coupled with poor pharmacokinetics (a short half-life), have hampered the delivery of cytokines via systemic administration, particularly because of severe dose-limiting toxicities. New engineering approaches have been developed to widen the therapeutic window, prolong pharmacokinetic effects, enhance tumor targeting and reduce adverse effects, thereby improving therapeutic efficacy. In this review, we focus on the recent progress and competitive landscape in cytokine engineering strategies and preclinical/clinical therapeutics for cancer. In addition, aiming to promote engineered cytokine-based cancer immunotherapy, we present a profound discussion about the feasibility of recently developed methods in clinical medicine translation.

A Critical Analysis of Nonsurgical Treatment of Peyronie’s Disease

OBJECTIVE

Because the efficacy of nonsurgical therapy of Peyronie's disease is controversial, this review analyses the current status of conservative therapy of Peyronie's disease.

METHOD

A systematic survey on results of studies published as original papers in peer-reviewed journals is provided.

RESULTS

Oral drug therapies include potassium para-aminobenzoate (Potaba), vitamin E, colchicine, tamoxifen, propoleum, acetyl-L-carnitine, and propionyl-L-carnitine. Verapamil, interferon-alpha2a and interferon-alpha2b, collagenase, cortisone, hyaluronidase, and superoxide dismutase are considered intralesional therapies that have had various degrees of success. Other treatments include local gels, iontophoresis, extracorporeal shock wave therapy, and radiation.

CONCLUSION

This review analyses the current status of the conservative therapy of Peyronie's disease, because the efficacy of the nonsurgical therapy is controversial.

The Impact of Intralesional Interferon α‐2b Injection Therapy on Penile Hemodynamics in Men with Peyronie's Disease

INTRODUCTION

Penile duplex Doppler ultrasound (PDDU) is currently the preferred method for the functional evaluation of penile hemodynamics. PDDU may be used to monitor objectively changes in penile vascular parameters in men who undergo treatment for Peyronie's disease (PD), including intralesional interferon alpha-2b (IFN alpha-2b).

AIM

To investigate the impact of intralesional IFN alpha-2b therapy for PD on penile hemodynamics by using PDDU and to assess the objective role of PDDU in monitoring treatment outcomes.

MATERIALS AND METHODS

Thirty-nine patients (20 in the placebo and 19 in the IFN alpha-2b treatment arm) were enrolled in this prospective, placebo-controlled, parallel study. Patients received either 10 mL saline or 5 x 10(6) units of IFN alpha-2b intralesional injections every other week for a total of six injections. Patients in each group were evaluated at baseline and after completion of treatment regarding changes in penile hemodynamic parameters, penile curvature, plaque size and density, pain on erection, and erectile function. Specific published criteria were used for PDDU measurements. Outcomes were statistically compared between each group by using Mann-Whitney U and chi-square tests.

RESULTS

The mean age of the patients and the duration of PD were similar in both groups. The improvement in penile blood flow was significantly greater in IFN alpha-2b-treated patients than those in the placebo group. The number with the nonvascular classification increased significantly in the IFN alpha-2b arm from 31.5% to 57.8%. Additionally, improvements in penile curvature, plaque size and density, and pain on erection were better in the IFN alpha-2b group compared with the control. No significant improvement was observed in the erectile function domain in either group.

CONCLUSION

This study reveals that intralesional IFN alpha-2b injections have a significant benefit on penile hemodynamic parameters. Moreover, intralesional IFN alpha-2b is an effective, minimally invasive treatment for PD, and PDDU is a useful adjunct to monitor objectively changes in penile vascular parameters. interferon alpha-2b injection therapy on penile hemodynamics in men with Peyronie's disease.

A pilot study to test the efficacy of oral administration of interferon-alpha lozenges to patients with Sjögren's syndrome

BACKGROUND

Complications from Sjögren's syndrome-induced xerostomia may cause a significant disruption in daily routines such as speech and eating habits. In addition, the reduction in salivary output may lead to increased incidence of caries, oral ulcers, sialadenitis, periodontal problems, and Candida infections. Interferon-alpha has been suggested as an effective drug therapy to increase salivary output.

OBJECTIVE

The objective was to test the efficacy of interferon-alpha lozenges in relieving the symptoms of dry mouth and dry eyes when administered orally to patients with Sjögren's syndrome in double-blind placebo-controlled and open-label trials.

STUDY DESIGN

Twelve patients with a diagnosis of primary Sjögren's syndrome were provided an Institutional Review Board-approved, written informed-consent form. During the double-blind placebo-controlled study they were randomized to receive 150 IU of interferon-alpha (8 patients) or placebo (4 patients) for 24 weeks with 6-week reevaluations. Five patients who received interferon-alpha in the double-blind placebo-controlled trial were treated in an open-label study for another 24 weeks. Whole saliva was measured during each visit, and symptoms were assessed by questionnaires and visual analog scales. The Wilcoxon signed rank test was used to detect significant changes for each variable.

RESULTS

The results indicated that, by the end of 24 weeks, patients who received interferon-alpha had a statistically significant improvement in unstimulated salivary flow rate (P < .05), and statistically significant changes were observed in the median ocular dryness visual analog scale (P < .05) and oral dryness visual analog scale (P < .05). No significant changes were observed among the placebo patients. By the end of 48 weeks, medicated patients had better results than they had at the end of the double-blind placebo-controlled study and showed improvements in whole stimulated salivary flow rate, conditions of throat, and swallowing dry food.

CONCLUSION

Oral administration of 150 IU interferon-alpha 3 times a day for the patients with primary Sjögren's syndrome improved saliva production, relieved symptoms of xerostomia and xerophthalmia, and was well tolerated by the patients.

Ingested type I interferon: a potential treatment for autoimmunity

We have proposed a unifying hypothesis of the etiopathogenesis of autoimmunity that defines autoimmunity as a type I interferon (IFN) immunodeficiency syndrome. We have examined toxicity and potential efficacy in three phase I (type 1 diabetes, rheumatoid arthritis, multiple sclerosis) and one phase II clinical trials in multiple sclerosis (MS). In a phase I open-label trial in type 1 diabetes, ingested IFN-alpha preserved residual beta cell function in recent onset patients. In a second phase I trial, treatment of rheumatoid arthritis (RA) with ingested IFN-alpha reduced the secretion of interleukin-1 (IL-1), a proinflammatory cytokine. In a third phase I trial in MS, there was a significant decrease in peripheral blood mononuclear cell (PBMC) IL-2 and IFN-gamma production after ingesting IFN-alpha. In a phase II randomized, placebo-controlled, double-blind trial in MS, 10,000 IU ingested IFN-alpha significantly decreased gadolinium enhancements compared with the placebo group at month 5. Tumor necrosis factor-alpha (TNF-alpha) and IFN-gamma cytokine secretion in the 10,000 IU group at month 5 showed a significant decrease that corresponded with the effect of ingested IFN-alpha on decreasing gadolinium enhancements. Ingested IFN-alpha was not toxic in any of these clinical trials. These studies suggest that ingested IFN-alpha may have a potential role in the treatment of autoimmunity.

Intralesional interferon-alpha-2b for the treatment of Peyronie's disease

Peyronie's disease can best be described as a localized connective tissue disorder that primarily affects the tunica albuginea of the penis. The disease may be attributed to repetitive vascular trauma that initiates an inflammatory process and ultimately leads to the formation of a fibrous penile plaque. The plaque consists mainly of collagen and can significantly alter penile anatomy and function. Patients with Peyronie's disease will most often present with penile curvature, pain on erection, a palpable nodule most commonly located on the dorsal shaft of the penis, and erectile dysfunction. There is no definitive treatment for Peyronie's disease and the treating physician has many options. They may wait for spontaneous resolution of the plaque, choose medical therapy (which includes both oral and intralesional regimens), or opt for surgical management. The main purpose of this article is to discuss the advances in medical therapy for Peyronie's disease, in particular intralesional injection of interferon-alpha-2b (IFN-alpha-2b). Several studies have concluded that IFN-alpha-2b can be an effective modality of treatment and that many patients placed on a regimen of IFN-alpha-2b experienced a significant reduction in penile curvature, diminished pain with erection, and decreased size of the plaque. Further clinical studies are currently being undertaken to determine the precise quantity and frequency of administration of IFN-alpha-2b that is most effective with the least amount of side effects.

Effects of recombinant ovine interferon-tau on ovine lentivirus replication and progression of disease

The antiviral effects of recombinant ovine interferon-tau (roIFN-tau) were studied in 26 lambs inoculated with ovine lentivirus (OvLV) or mock-infected. Six of the OvLV-infected lambs and three of the mock-infected lambs were treated with 10(6) antiviral units (AVU) per kg roIFN-tau daily for 30 days starting at day 0 post-inoculation (p.i.) and twice a week thereafter (early treatment). Six of the OvLV-infected lambs and three of the mock-infected lambs were treated with 10(6) AVU/kg roIFN-tau daily for 30 days starting at day 150 p.i. and twice a week thereafter (late treatment). Six OvLV-infected and two mock-infected lambs were treated either early or late with placebo. Cell-associated viraemia was quantified by an end-point dilution method. The weekly antibody response against OvLV proteins was studied by ELISA. All experimental animals were killed at 27 weeks p.i. and histological sections of lung were scored for the degree of lymphoid interstitial pneumonia (LIP). A 90% reduction in OvLV titres was detected at 4 weeks post-treatment in lambs that received early roIFN-tau treatment (P<0.01). Differences in virus titres were also found at weeks 2 and 6 (P<0.05). Scores for LIP degree were higher in infected lambs treated with placebo or late roIFN-tau than in the mock-infected lambs or in the infected lambs that received early roIFN-tau (P<0.05). LIP scores were not different between mock-infected lambs and infected lambs that received early roIFN-tau. These results indicate that roIFN-tau curtails OvLV replication in vivo and reduces the likelihood of development of lentivirus-induced LIP when infected lambs are treated during the initial phases of OvLV infection.

Hybrid (BDBB) interferon-alpha: preformulation studies

A number of techniques, including RP-HPLC, HP-SEC and SDS-PAGE have been used in the delineation of degradative mechanisms of recombinant hybrid (BDBB) interferon-alpha (IFN-alpha) in the solution phase. Different degradation profiles are found according to medium pH. At pH 4.0 the major routes of degradation are via chemical transformation of the monomeric protein to a species which retains antiviral activity, and by self-proteolytic hydrolysis. At pH 7.6, methionine-oxidation is the major chemical degradative process. Protein aggregation is also a significant route of degradation at the higher pH. The results have assisted in a targeted preformulation screen of potentially stabilising excipients and possible parenteral solution dosage forms have been identified. Preliminary 'real-time' storage data confirm excellent chemical and physical stability of IFN-alpha in vehicles formulated at pH 7.6 or, especially, pH 4.0 under the proposed shelf conditions.

Effects of recombinant interferon-tau on ovine lentivirus replication

As a pregnancy recognition signal, sheep trophoblast cells secrete a type I interferon, ovine interferon-tau (OvIFN-tau), which has potent antiviral activity. We studied the effects of a recombinant protein (rOv-IFN-tau) on the replication of ovine lentivirus (OvLV) in goat synovial membrane cells. The amount of provirus DNA, as measured by polymerase chain reaction (PCR), the virus titers, and the number of OvLV-induced syncytia were 76.5%, 82%, and 95%, respectively, lower in cultures treated with rOv-IFN-tau than in placebo-treated controls (p < 0.01). rOv-IFN-tau also reduced OvLV reverse transcriptase activity and protected cells from OvLV-induced cell lysis, but the effect was less dramatic. The antiviral activity increased with the concentration up to a maximum with 256 antiviral units of rOv-IFN-tau per ml.

Recombinant alpha-2B interferon treatment for childhood T--lymphoblastic disease in relapse. A Pediatric Oncology Group Phase II study

BACKGROUND

Children with chemotherapy refractory T-cell lymphoblastic leukemia/lymphoma were given alpha-interferon (alpha-IFN) to evaluate the efficacy and toxicity of this biologic response modifier.

METHODS

Twenty children with T-cell acute lymphoblastic leukemia (T-cell ALL) in marrow relapse and one patient with mediastinal recurrence of T-cell non-Hodgkin's lymphoma (T-cell NHL) were enrolled. All patients had failed at least two previous multiagent drug trials. Recombinant alpha-IFN was given at 30 million U/M2/dose intravenously or subcutaneously for 10 doses over 14 days, followed by 3 doses per week until disease progression occurred.

RESULTS

One child had a complete response (< 5% blasts) and three patients a partial response (5-25% blasts) in their bone marrow. All patients eventually showed signs of progressive disease. Significant toxicities included cardiac hypofunction in two patients and profound lethargy in two patients.

CONCLUSIONS

alpha-IFN is tolerated in children with T-cell ALL and T-cell NHL and has activity against chemotherapy resistant disease.