The effect of interferon on human papillomaviruses associated with cervical intraepithelial neoplasia

Effect of Perilesional Injection of α-interferon on Cervical Intraepithelial Neoplasia and Associated Human Papillomavirus Infection

In this controlled prospective study, 14 patients with cervical intraepithelial neoplasia (CIN) were observed for one month to exclude spontaneous regression, and then seven patients were treated twice-weekly with perilesional injections of alpha-interferon. Both groups were monitored colposcopically, and advised to use the contraceptive sheath. Cervical smears and biopsies for histology and viral studies were taken before and after the study. There was an improvement of six out of seven of the study group, with two complete cures. Koilocytosis disappeared if it had been present initially, as did human papillomavirus (HPV) 16. By contrast, three control cases showed improvement, but there were no cures, and one case deteriorated; Koilocytosis (2 cases) did not change; HPV 16 disappeared in two controls and appeared in one. A new focus of dysplasia appeared in a part of the transformation zone not being treated with alpha-interferon in one of the study cases, illustrating the advisability of treating the whole transformation zone in CIN.

Utilization of Interferon in Gynecologic and Breast Cancer

The usual treatment of gynecologic cancer has been surgery, chemotherapy and radiotherapy. New therapies are being developed to improve efficacy of treatment. Interferons are inducible secretory glycoproteins that have immunomodulatory, antiviral, anti-angiogenic and anti-proliferative effects. Their potential antitumor effect has been demonstrated in many studies. Some patients obtain beneficial effects; in other patients the treatment failure can occur. IFNs can modulate the immune response and inhibition of tumor angiogenesis. When any alteration in gene expression occurs, there is modulation of the receptors of other cytokines and enzymes that control cell function. These alterations can influence the differentiation, cell proliferation rate and apoptosis. The molecular mechanisms that control apoptotic cell death can be improved through cancer management using IFN in single, combination or adjuvant treatment. Malignant cells generally present defects in programmed cell death and apoptosis. Immunomodulation and angiogenesis inhibition are indirect antitumor mechanisms mediated by apoptosis. With regard to immunomodulation, IFNs can have antitumor effects through increases in cytotoxic T cells, natural killer cells and dendritic cells. Angiogenesis inhibition can result from endothelial cell apoptosis. This factor is important in inhibiting tumor genesis and forming metastases. The aim of this review is to discuss the role of Interferon in the treatment of gynecologic malignancies/breast cancer and mechanisms of action.

Potential of interferon-alpha in solid tumours: part 2

The second part of this review examines the use of recombinant interferon-alpha (rIFNalpha) in the following solid tumours: superficial bladder cancer, Kaposi's sarcoma, head and neck cancer, gastrointestinal cancers, lung cancer, mesothelioma and ovarian, breast and cervical malignancies. In superficial bladder cancer, intravesical rIFNalpha has a promising role as second-line therapy in patients resistant or intolerant to intravesical bacille Calmette-Guérin (BCG). In HIV-associated Kaposi's sarcoma, rIFNalpha is active as monotherapy and in combination with antiretroviral agents, especially in patients with CD4 counts >200/mm(3), no prior opportunistic infections and nonvisceral disease. rIFNalpha has shown encouraging results when used in combination with retinoids in the chemoprevention of head and neck squamous cell cancers. It is effective in the chemoprevention of hepatocellular cancer in hepatitis C-seropositive patients. In neuroendocrine tumours, including carcinoid tumour, low-dosage (</=3 MU) or intermediate-dosage (5 to 10 MU) rIFNalpha is indicated as second-line treatment, either with octreotide or alone in patients resistant to somatostatin analogues. Intracavitary IFNalpha may be useful in malignant pleural effusions from mesothelioma. Similarly, intraperitoneal IFNalpha may have a role in the treatment of minimal residual disease in ovarian cancer. In breast cancer, the only possible role for IFNalpha appears to be intralesional administration for resistant disease. IFNalpha may have a role as a radiosensitising agent for the treatment of cervical cancer; however, this requires confirmation in randomised trials. On the basis of current evidence, the routine use of rIFNalpha is not recommended in the therapy of head and neck squamous cell cancers, upper gastrointestinal tract, colorectal and lung cancers, or mesothelioma. Pegylated IFNalpha (peginterferon-alpha) is an exciting development that offers theoretical advantages of increased efficacy, reduced toxicity and improved compliance. Further data from randomised studies in solid tumours are needed where rIFNalpha has activity, such as neuroendocrine tumours, minimal residual disease in ovarian cancer, and cervical cancer. A better understanding of the biological mechanisms that determine response to rIFNalpha is needed. Studies of IFNalpha-stimulated gene expression, which are now feasible, should help to identify molecular predictors of response and allow us to target therapy more selectively to patients with solid tumours responsive to IFNalpha.

The effects of interferon on the expression of human papillomavirus oncogenes

The effects of interferon (IFN)-alpha, IFN-beta and IFN-gamma on human papillomavirus (HPV) oncogene expression were studied in various cervical carcinoma cell lines containing integrated copies of either HPV type 16 or HPV type 18. The levels of E6 and E7 transcripts were examined 6 h and 30 h after treatment with IFN. In HeLa cells, all three classes of IFNs effected a decrease in the level of HPV-18 E6 and E7 transcripts. On the other hand, none of the IFNs altered the level of these transcripts in C-4II cells. Only IFN-gamma decreased the level of HPV-16 E6 and E7 transcripts in CaSki and HPK1A cells, while IFN-gamma actually increased the level of these transcripts in SiHa cells. This differential IFN regulation of HPV expression in various cervical cancer cell lines may account for the contradictory clinical results observed after treatment of cervical cancer with IFN.

Interferons alpha, beta and gamma therapy of anogenital human papillomavirus infections

Anogenital condyloma acuminatum (genital warts) is the most commonly diagnosed sexually transmitted viral disease in the United States. At least 14 of the more than 60 types of human papillomaviruses (HPVs) are responsible for condyloma acuminatum. Anogenital condyloma acuminatum has a broad spectrum of manifestations in men and women, including subclinical latent infection, clinically apparent warts, abnormal genital cytology and squamous carcinoma. Traditional therapeutic modalities include cytolytic chemical agents and ablative techniques. These anti-wart methods are used in an attempt to eliminate clinically apparent disease. However, they are associated with high rates of recurrence because they do not eradicate the subclinical or latent reservoir of HPV remaining in adjacent epithelial cells and mucous membranes. Immunologic therapy with interferons (IFNs) represents a promising new antiviral modality that can be directed against all sites of infection, including clinical, subclinical and latent disease. IFN-alpha, IFN-beta and IFN-gamma are the three major groups of IFNs. These three groups of IFNs have been used successfully as monotherapy or in combination with traditional modalities to treat anogenital condyloma acuminatum. This review focuses on IFN-alpha, IFN-beta and IFN-gamma therapy of anogenital HPV infections.

Efficacy trial of topically administered interferon gamma-1 beta gel in comparison to laser treatment in cervical intraepithelial neoplasia

OBJECTIVE

Dose dependent response of cervical intraepithelial neoplasia (CIN) to topically administered interferon (IFN) gamma was assessed and compared with conventional laser therapy.

PATIENT AND METHODS

33 women were included in a randomized phase II trial which was double blinded for IFN dosages. Twenty-four patients received IFN gamma-1 beta gel and a control group of nine patients was treated with laser surgery. 18 patients had smears suggesting CIN II and 15 patients had smears suggesting CIN III. The response was assessed 6 months after starting of IFN gamma-1 beta treatment or having laser surgery.

RESULTS

Topical IFN gamma-1 beta treatment gave a cure rate of 42% independent of IFN dosage as compared to an 89% cure rate with laser therapy (P = 0.02). Patients with CIN II responded better compared with patients with CIN III. Current smokers showed a significantly lower cure rate whereas use of oral contraceptives (OC) did not influence response. High viral load with high risk types of human papillomaviruses (HPV) was associated with a better response.

Interferons in human papillomavirus infections

Human papillomavirus (HPV) infections usually present as benign warts (e.g., condyloma acuminatum, CA) but can also be responsible for dysplasia and carcinoma. Therapeutic options include chemotherapeutic agents, cryotherapy and surgery, but all these treatments are anti-tumor, not anti-viral. Interferons (IFNs) are the only anti-viral drugs approved for the therapy of benign HPV-related lesions. While IFN-alpha, IFN-beta and IFN-gamma have all been tested against CA, most information is available on IFN-alpha which appears efficacious via a number of routes of administration, schedules and dosages with an acceptable safety profile. The highest rate of success with IFN-alpha therapy, in terms of reduced recurrence rates of CA was reported from studies in which all visible lesions were surgically removed with subsequent administration of subcutaneous local IFN-alpha. Less data is available on the efficacy of IFNs in the treatment of HPV-related dysplasia and carcinoma, but combination therapy (e.g., IFN-alpha plus retinoids for cervical carcinoma) appears promising. Future advances in control of HPV-related lesions are expected to continue to involve IFN combined with non-antiviral therapies as well as the use of exogenous inducers of IFNs and other cytokines.

Clinical study with recombinant interferon gamma versus interferon alpha-2c in patients with condylomata acuminata

A multi-centre, randomized, open-label trial was conducted to evaluate the safety and efficacy of recombinant interferon (rIFN) alpha-2c versus rIFN gamma in patients with recurrent or persistent condylomata acuminata (CA). Thirty-three such patients were treated either with 6 micrograms rIFN alpha-2c or with 0.1 mg rIFN gamma (both equivalent to 2 x 10E6 IU), single dose, subcutaneously 3 times a week for 6 weeks. In case of no complete clearance at week 10, a second course of treatment with the other type of rIFN was given. There was no significant difference in the complete clearance proportions at week 10 between the two treatment groups (3/16 vs 6/17). No relapses occurred in these patients during the 16 weeks' follow-up. Further clearances during the follow-up resulted in a total complete clearance proportion of 14/33 at the end of study. The treatment was well tolerated. Repeated interferon therapy has its place in treating persistent or recurrent condylomas.

Systemic alpha-interferon (Wellferon) treatment of genital human papillomavirus (HPV) type 6, 11, 16, and 18 infections: double-blind, placebo-controlled trial

The efficacy of systemic interferon-alpha (IFN-alpha n1; Wellferon) treatment on genital human papillomavirus (HPV) infections was studied in a double-blind, placebo-controlled trial. A total of 120 women were randomly allocated to receive either interferon (IFN, n = 60) or placebo (n = 60). In both treatment groups, 15 patients with lesions induced by each of the four HPV types (HPV 6, 11, 16, and 18) were included. The dose of IFN was 1.5 x 10(6) IU subcutaneously three times for the first week followed by 3 x 10(6) IU three times weekly for a further 6 weeks. The control patients received matching placebo injections. Ten patients (three IFN-treated and seven placebo-treated) were lost to follow-up. As determined by colposcopy, cytological and histological examinations, and HPV typing (in situ hybridization, ISH), 8 IFN-treated patients (14%) and 11 placebo-treated patients (18%) showed complete response (CR) at the 8th week. The corresponding figures were 22 (37%) and 25 (43%) at the 24th week and 28 (49%) and 25 (49%) at the 52nd week, respectively. The total number of HPV DNA negative patients at Week 8 was 29 (49%) in the IFN group and 24 (40%) in the placebo group (statistically nonsignificant). At Week 24, 37 (63%) of the IFN-treated patients and 39 (67%) of the placebo-treated patients were HPV DNA negative. In 2 placebo-treated cases, cervical lesions progressed to CIN III and were treated by conization after the 24th week. There were 4 recurrences (7%) in the IFN group and no recurrences in the placebo group at the 24th week, corresponding figures at the 52nd week being 6 (11%) and 4 (7%), respectively. When the clinical efficacy was evaluated in relation to the histological grade of lesion and four different HPV types, there were no differences in CR or in the number of HPV DNA negative patients between the two study groups. In conclusion, systemic IFN-alpha therapy did not show any significant therapeutic effect on genital HPV infections (by HPV types 6, 11, 16, and 18) compared to placebo.

Efficacy of interferons on bowenoid papulosis and other precancerous lesions

Preliminary results of an open randomized trial of recombinant interferon gamma in patients suffering from bowenoid papulosis are described. Recombinant interferon gamma was given subcutaneously to 12 patients at a daily dose of 4 X 10(6) I.U. by injection. Four patients each were assigned to one of three treatment groups consisting of continuous therapy (group A) with three subcutaneous injections per week for 13 weeks; intermittent block therapy (group B) with four six-week cycles consisting of five injections on days 1, 3, 5, 7, and 9 of each cycle; and intermittent single-dose therapy (group C) with six four-week cycles consisting of only one subcutaneous injection on day one of each cycle. At the twenty-sixth week after onset of therapy, complete responses were seen in three of four patients of treatment group A, whereas in the treatment groups B and C only one patient, respectively, responded partially. These results suggest that in contrast to condylomata acuminata bowenoid papulosis lesions respond better to continuous than to intermittent interferon gamma injections.

No effect of intralesional injection of interferon on moderate cervical intraepithelial neoplasia

Women with histologically confirmed cervical intraepithelial neoplasia grade 2 (CIN 2) were treated in a double blind investigation of treatment with intralesioneal interferon alpha-2b (Intron a). Before treatment commenced, the existence and the types of human papilloma-virus (HPV) were assessed in [35S] methionine-labelled cervical biopsies by the determination of specific protein markers. Pronounced side effects occurred in all the women treated with interferon and the trial was stopped when it became apparent that there were no obvious beneficial effects. No positive benefits of interferon treatment were detected on either the CIN 2 or on the persistence of HPV types. It is concluded that intralesioneal injection of interferon has no place in the treatment of CIN.

Topical treatment with human leukocyte interferon of HPV 16 infections associated with cervical and vaginal intraepithelial neoplasias

The present placebo-controlled, double-blind trial was designed to determine the effect of potent human leukocyte interferon cream (IFN) on genital HPV 16 (high-risk-type) infections associated with cervical intraepithelial neoplasia (CIN) and/or vaginal intraepithelial neoplasia (VAIN). Twenty women were treated with either IFN or placebo cream. The daily dose of IFN was 9 x 10(6) IU. The patients applied the cream deep into the vagina every night for 2-week courses 1 week apart. The entire treatment period was 12 months. On the basis of colposcopical, cytological, and histological examinations, 4 of 9 patients in the IFN group and 7 of 10 patients in the placebo group showed clinical remissions at the end of the trial. However, the virological studies gave a different picture. After treatment, 6 of 9 in the IFN group and 3 of 10 in the placebo group were HPV 16 DNA negative (in situ hybridization). All four patients in remission after IFN were HPV 16 DNA negative, whereas 4 of 7 patients in remission after placebo were still HPV 16 DNA positive. One patient treated with placebo showed progression; no patient in the IFN group showed progression. During the post-treatment follow-up of 16 months, no recurrences were noted in the IFN group, as compared with 2 of 10 in the placebo group. These results showed a marked discrepancy between clinical evaluation (colposcopy, Pap smear, biopsy) and virological findings. Further studies are needed to clarify the prognostic value of the different evaluation criteria. It is encouraging that the high-risk HPV 16 infection was eradicated in two-thirds of the patients treated with topical IFN.

Interferon-alpha in treatment of intraepithelial neoplasia of the lower genital tract: a case report

A patient with persistent intraepithelial neoplasia of the vulva, vagina and cervix was treated with subcutaneous injections of interferon-alpha-2b. Previous surgical and laser procedures had failed. HPV subtype 16 was found in biopsies from all sites and an immunological screening was performed before and after therapy. Histologically proven regression of the intraepithelial neoplasia was seen at all sites, with a complete remission of the cervical lesions. The role of interferon in treatment of intraepithelial neoplasia is discussed.