Lack of efficacy of interferon-alpha therapy in recurrent, advanced cervical cancer

Efficacy and Safety of Immunotherapy for Cervical Cancer—A Systematic Review of Clinical Trials

Purpose: To systematically review the current body of evidence on the efficacy and safety of immunotherapy for cervical cancer (CC). Material and Methods: Medline, the Cochrane Central Register of Controlled Trials and Web of Science were searched for prospective trials assessing immunotherapy in CC patients in compliance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Full-text articles in English and German reporting outcomes of survival, response rates or safety were eligible. Results: Of 4655 screened studies, 51 were included (immune checkpoint inhibitors (ICI) n=20; therapeutic vaccines n = 25; adoptive cell transfer therapy n=9). Of these, one qualified as a phase III randomized controlled trial and demonstrated increased overall survival following treatment with pembrolizumab, chemotherapy and bevacizumab. A minority of studies included a control group (n = 7) or more than 50 patients (n = 15). Overall, response rates were low to moderate. No response to ICIs was seen in PD-L1 negative patients. However, few remarkable results were achieved in heavily pretreated patients. There were no safety concerns in any of the included studies. Conclusion: Strong evidence on the efficacy of strategies to treat recurrent or metastatic cervical cancer is currently limited to pembrolizumab in combination with chemotherapy and bevacizumab, which substantiates an urgent need for large confirmatory trials on alternative immunotherapies. Overall, there is sound evidence on the safety of immunotherapy in CC.

Defective dendritic cell generation from monocytes is a potential reason for poor therapeutic efficacy of interferon α2b (IFNα2b) in cervical cancer

Despite being a pleiotropic cytokine, the therapeutic potential of interferon α2b (IFNα2b) is debatable. Thus, the need for identifying predictive marker(s) for patients who are most likely to benefit from the treatment is pivotal for avoiding the exposure of nonresponsive patients to the toxicity of the treatment. To account for the attenuated efficacy of the drug, we have verified its dendritic cell (DC) maturating ability from monocytes of cervical cancer stage IIIB (CaCx-IIIB) patients. First, we evaluated the status of monocytes from CaCx-IIIB and healthy women by conducting flow cytometric studies of various activation markers and a cytokine analysis by enzyme-linked immunosorbent assay (ELISA) and flow cytometry. Immature DCs were then generated from these monocytes and matured with low-dose IFNα2b (1500 units/mL). A functional and phenotypic comparative analysis of these matured DCs was performed by flow cytometric, proliferative, cytotoxic, and enzyme-linked immunosorbent assays. Our study shows that monocytes isolated from CaCx-IIIB are impaired, and in vitro maturation with IFNα2b did not significantly improve the functional repertoire of DCs generated from these monocytes in comparison with healthy controls. This impairment of monocytes might be a plausible reason for the attenuated efficacy of this drug alone in treating CaCx-IIIB patients, and this imbalance of immune parameters associated with the stage of malignancy might be considered an effective marker to design a proper therapeutic regimen.

Stromal issues in cervical cancer: a review of the role and function of basement membrane, stroma, immune response and angiogenesis in cervical cancer development

The carcinogenesis of cervical carcinoma implies an intricate interplay of neoplastic, human papillomavirus infected epithelial cells and stromal tissue, in which different factors have distinct but interacting influence. Persistent infection with an oncogenic human papillomavirus type may lead to epithelial dysplasia with progressive severity. To access the adjacent stromal tissue, tumour cells have to breach the basement membrane. The stroma partly controls tumour growth, invasion and angiogenesis. Last but not least there is considerable influence of the immune response. In this review we describe the importance of various stromal factors in carcinogenesis of cervical cancer.

A phase II trial of interleukin-12 in patients with advanced cervical cancer: clinical and immunologic correlates. Eastern Cooperative Oncology Group study E1E96

PURPOSE

The ability to mount lymphoproliferative responses to peptides derived from the human papillomavirus (HPV) E6 and E7 oncoproteins has been associated with regression of dysplastic lesions of the uterine cervix and loss of associated HPV infection. Interleukin-12 (IL-12) is a potent immunopotentiator of T-cell function, and has been shown in phase I clinical trials to be tolerable.

EXPERIMENTAL DESIGN

Patients were required to have measurable metastatic, recurrent or inoperable cervical carcinoma. Patients could have had one prior adjuvant regimen and one prior regimen for advanced disease. Treatment consisted of IL-12 administered at 250 ng/kg IV as a rapid push in the outpatient setting daily x 5 every 21 days. Whole blood samples were acquired twice before treatment then approximately every 3 weeks to assess lymphoproliferative response in vitro to HPV type 16 (HPV 16) E4, E6, and E7 peptides. These responses were correlated with demographics and with clinical outcome.

RESULTS

Thirty-four patients were enrolled; 29 were evaluable. Over half had received cisplatin-based chemotherapy. The most common serious toxicities were hematologic or hepatic, and all were reversible. There was one partial responder (3%). The median survival was 6.5 months (95% CI: 5.8, 11.5 months). Eighteen of 29 eligible patients had evaluable laboratory data both pre- and post-therapy. There was a statistically significant increase in lymphoproliferative responses for HPV 16 E4, E6, and E7 peptides (P=0.020, 0.020, 0.043). There was a significant association between change in lymphoproliferative response to HPV 16 E6 peptides and number of cycles of treatment administered (P=0.048). There was no correlation between change in lymphoproliferative response to any peptide with age, performance status, race, prior chemotherapy, time from diagnosis to treatment, or with overall survival.

CONCLUSIONS

IL-12 treatment was associated with improved lymphoproliferative responses to HPV 16 E4, E6, and E7 peptides. This is the first clinical trial to demonstrate induction of cell-mediated immune (CMI) responses to specific antigens (peptides) following treatment with IL-12 in women with cervical cancer. This improvement in immune response was not associated with enhanced objective response or survival.

Alpha interferon augments cidofovir's antiviral and antiproliferative activities

The antiviral and antiproliferative activities of alpha 2a interferon (IFN-alpha 2a) and cidofovir in human papillomavirus type 16 (HPV-16)-transformed keratinocytes were evaluated. The compounds in combination were more effective than comparable levels of either drug alone. Evaluation of effective drug ratios revealed a synergistic cooperation between IFN-alpha 2a and cidofovir in inhibiting the proliferation of HPV-infected cells.

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.

Cidofovir, a new approach for the treatment of cervix intraepithelial neoplasia grade III (CIN III)

Cervix intraepithelial neoplasia grade III (CIN III) is an intraepithelial proliferative process with different levels of severity depending on both the extension of the proliferation in the epithelium and the presence of cellular atypia. Human papillomavirus (HPV) has been clearly associated with such lesions. The results of a preliminary study are described on the local application of cidofovir, an acyclic nucleoside phosphonate derivative with broad-spectrum anti-DNA virus activity for the treatment of CIN III. Cidofovir 1% in gel was applied three times, every other day, on the cervix of each of 15 women with biopsy proven CIN III. Within 1 month after the start of treatment, the cervix was removed surgically. Histology and human papillomavirus polymerase chain reaction (HPV-PCR) were carried out. In 7 of the 15 patients the histology showed a complete response, whereas 5 patients had a partial response characterized by the persistence of CIN II-III lesions, 1 patient had a dysplasia of lower grade (CIN I), and 2 patients did not show differences in the histology. Complete response was confirmed by PCR in 4 of the 7 patients, with complete response histologically. Cidofovir was not toxic to the normal epithelium. Cidofovir 1% gel was able to inhibit partially or completely cervical dysplasia lesions after only three applications (every other day). This effect was specific and tissue other than the dysplastic epithelium was not affected by the treatment.

IFN-tau exhibits potent suppression of human papillomavirus E6/E7 oncoprotein expression

The effects of interferon-tau (IFN-tau) on tumor suppressor factors and virus oncoprotein expression were compared with two other type I IFN in human papillomavirus (HPV-16)-transformed cells. Nontumorigenic human keratinocytes, HuKc/HPV-16d-2C (d-2C), treated with recombinant human IFN-alpha2a (Roferon), a human recombinant alpha IFN hybrid, alpha B/D (IFN-alphaB/D), or ovine IFN-tau were evaluated for their effects on the levels of E6 and E7 expression. IFN-tau was comparable to IFN-alpha2a in decreasing intracellular levels of E6 and E7, and IFN-alphaB/D was more effective than IFN-a2a in suppressing E7 levels. All three IFN were capable of increasing the cellular concentration of wild-type p53 tumor suppressor with the magnitude IFN-tau > IFN-alpha2a > IFN-alphaB/D. Increases in p53 concentrations correlated with the observed decreases in E6 mRNA and protein levels. The antiviral effects observed in this study reveal that IFN-tau has potent antipapillomavirus activity. Sequences/structures unique to IFN-tau could allow for alternative IFN/receptor interactions and may explain the differences in biologic function.

All-trans retinoic acid and interferon-alpha-2a in patients with metastatic or recurrent carcinoma of the uterine cervix: clinical and pharmacokinetic studies. New York Gynecologic Oncology Group

BACKGROUND

Recent clinical trials with a combination of interferon (IFN alpha) and 13 cis-retinoic acid resulted in high response rates among women with locally advanced and metastatic carcinoma of the uterine cervix. The authors sought to amplify these observations by employing the isomer of 13 cis-retinoic acid, all-trans retinoic acid (tRA), in combination with IFN alpha.

METHODS

Sequential clinical trials were initiated by the New York Gynecologic Oncology Group to test the combination of tRA and IFN alpha in women with metastatic or recurrent carcinoma of the cervix who had failed primary therapy. IFN alpha was administered at 6 MU subcutaneously 3 times per week. In the first trial, tRA was administered at 50 mg/m2 orally 3 times per day on a daily schedule (daily regimen), whereas in the second trial, tRA was administered at the same dose 3 times per day, but only on Days 1-3 each week (intermittent schedule). Clinical outcomes included response to therapy and survival. Plasma pharmacokinetic studies of tRA were performed in both trials to assess the effects of different schedules on plasma levels of the drug.

RESULTS

Fourteen women with metastatic or recurrent squamous cell carcinoma of the cervix were enrolled in the daily trial and 12 women in the intermittent trial. There was no clinical activity for either regimen, and both studies were terminated according to an early stopping rule. Because tRA has been reported to induce its own metabolism, plasma levels of tRA were measured on Days 1, 8, and 28. The change in the area under the time versus tRA concentration curve (AUC) was significantly different between the two groups. The average AUC on Day 8 was 14% of that observed on Day 1 for the daily treatment group; in contrast, it was 107% on Day 1 in the intermittent treatment group. In 6 of 8 patients studied in the daily trial, the AUC decreased at least 60% by either Week 2 or Week 4. In contrast, in the intermittent trial, only 3 of 9 patients experienced >60% decrease in plasma levels of the drug at either Day 8 or Day 28.

CONCLUSIONS

The combination of tRA + IFN alpha was inactive in patients with advanced carcinoma of the cervix when employed at these doses on either the daily or intermittent schedule. The failure of activity of this regimen did not result from induction of metabolism of tRA, suggesting that intrinsic mechanisms of resistance to tRA at the cellular level may be of greater importance.