13-cis retinoic acid and interferon-alpha +/- irradiation in the treatment of squamous-cell carcinomas

Combining Radiation Therapy With Interferons: Back to the Future

Radiation therapy has been linked to the induction of an intratumoral type I interferon (IFN) response, which positively affects the response to treatment. This has spiked the interest to combine radiation therapy with IFN-based treatment. Interestingly, this combination treatment has been considered previously, since preclinical studies demonstrated a radiosensitizing effect of interferons. As a result, multiple clinical trials have been performed combining radiation therapy with interferons in different tumor types. Although potential benefit has been suggested, the outcomes of the trials are diverse and challenging to interpret. In addition, increased grade ≥3 toxicity frequently resulted in a negative recommendation regarding the combination therapy. The latter appears premature because many studies were small and several aspects of the combination treatment have not yet been sufficiently explored to justify such a definite conclusion. This review summarizes the available literature on this combination therapy, with a focus on IFN-α and IFN-β. Based on preclinical studies and clinical trials, we evaluated the potential opportunities and describe the current challenges. In addition, we identify several issues that should be addressed to fully exploit the potential benefit of this combinatorial treatment approach.

Phase 2 Randomized Controlled Trial of Radiation Therapy Plus Concurrent Interferon-Alpha and Retinoic Acid Versus Cisplatin for Stage III Cervical Carcinoma

PURPOSE

Because a combination of retinoic acid, interferon-alpha, and radiation therapy demonstrated synergistic action and effectiveness to treat advanced cervical cancers in earlier studies, we designed this randomized phase 2 open-label trial to assess efficacy and safety of interferon alpha-2b (IFN) and 13-cis-retinoic acid (RA) administered concomitantly with radiation therapy (IFN-RA-radiation) to treat stage III cervical cancer.

METHODS AND MATERIALS

Stage III cervical cancer patients were randomized to study and control groups in a 1:1 ratio. All patients were treated with radiation therapy; study arm patients received IFN (3 × 10(6) IU subcutaneously) 3 times a week for 4 weeks and daily RA (40 mg orally) for 30 days starting on day 1 of radiation, whereas control arm patients received weekly cisplatinum (40 mg/m(2)) for 5 weeks during radiation. Patients were followed for 3 years. The primary endpoint was overall survival at 3 years.

RESULTS

Patients in the study (n=104) and control (n=105) groups were comparable for clinicopathological characteristics, radiation therapy-related variables and treatment response. Proportions of disease-free patients in the study and control groups were 38.5% and 44.8%, respectively, after median follow-up of 29.2 months. Hazard ratios were 0.67 (95% confidence interval [CI]: 0.44-1.01) and 0.69 (95% CI: 0.44-1.06) for overall and disease-fee survival, respectively, comparing the study group to control, and demonstrated an inferior outcome with RA-IFN-radiation, although differences were statistically nonsignificant. Kaplan-Meier curves of disease-free and overall survival probabilities also showed inferior survival in the study group compared to those in the control. Acute toxicities of chemoradiation were significantly higher with 2 acute toxicity-related deaths.

CONCLUSIONS

Treatment with RA-IFN-radiation did not demonstrate survival advantage over chemoradiation despite being less toxic. The trends predicted an inferior outcome with the RA-IFN combination.

The Florida Melanoma Trial I: A Prospective Multicenter Phase I/II Trial of Postoperative Hypofractionated Adjuvant Radiotherapy with Concurrent Interferon-Alfa-2b in the Treatment of Advanced Stage III Melanoma with Long-Term Toxicity Follow-Up

Radiotherapy (RT) and interferon-alfa-2b (IFN α-2b) have individually been used for adjuvant therapy stage III melanoma with high-risk pathologic features. We hypothesized that concurrent adjuvant RT and IFN α-2b may decrease the risk of regional recurrence following surgery with acceptable toxicity. A prospective multicenter phase I/II study was conducted to evaluate hypofractionated RT with concurrent IFN. Induction IFN α-2b, 20 MU/m2/d, was administered IV ×5 consecutive days every week for 4 weeks. Next, RT 30 Gy in 5 fractions was given with concurrent IFN α-2b, 10 MU/m2 SQ 3 times per week on days alternating with RT. Subsequent maintenance therapy consisted of adjuvant IFN α-2b, 10 MU/m2 SQ 3 times per week to a total of 1 year. To fully evaluate patterns of failure, long-term follow-up was conducted for up to 10 years. A total of 29 consenting patients were enrolled between August 1997 and March 2000. The maximum (worst) grade of acute nonhematologic toxicity during concurrent RT/IFN α-2b (and up to 2 weeks post RT) was grade 3 skin toxicity noted in 2 patients (9%). Late effects were limited. Probability of regional control was 78% (95% CI: 55%–90%) at 12 months. The median follow-up (range) was 80 (51–106) months among ten survivors (43%). The median overall survival was 34.5 months while the median failure-free survival was 19.9 months. Postoperative concurrent hypofractionated RT with IFN α-2b for advanced stage III melanoma appears to be associated with acceptable toxicity and may provide reasonable in-field control in patients at high risk of regional failure.

Expression of RARalpha and RARbeta in human oral potentially malignant and neoplastic lesions

Retinoids reverse potentially malignant lesions and inhibit the development of second primary cancers in patients with head-and-neck cancer. Many of the effects of retinoids result from modulation of gene expression by 2 distinct classes of nuclear receptor, RARs and RXRs; alterations in their expression can lead to tumorigenesis. To determine whether aberrations in expression of the receptors are related to the development of betel- and tobacco-related oral cancer, we used specific monoclonal antibodies against RARalpha and RARbeta to detect expression of these proteins in 30 histopathologically normal tissues, 45 potentially malignant lesions (leukoplakia) with histological evidence of either hyperplasia (31 cases) or dysplasia (14 cases) and 64 oral squamous-cell carcinomas (SCCs) by immunohistochemistry. Of the 30 normal oral tissues analysed, 8 cases showed detectable levels of RARalpha protein, while 10 cases did not show detectable RARbeta immunoreactivity. Immunostaining for RARalpha protein was observed in 12/31 (39%) hyperplastic lesions, 6/14 (43%) dysplastic lesions and 43/64 (67%) oral SCCs. Expression of RARalpha in oral SCC was significantly associated with the histological differentiation status of tumours (p = 0.016). In contrast, lack of detectable immunoreactivity was observed in 19/31 (61%) hyperplastic lesions, 8/14 (57%) dysplastic lesions and 21/64 (33%) oral SCCs. The hallmark of the study was the significant increase in RARalpha immunopositivity in oral SCCs compared to normal tissue (p = 0.0005) and hyperplastic lesions (p = 0.016). One intriguing feature was the significant decrease in RARbeta immunopositivity in hyperplastic lesions compared with normal oral mucosa (p = 0.05) as well as in oral SCCs compared with normal tissues (p = 0.0008).

Retinoids in lung cancer chemoprevention and treatment

In this review, we aim to synthesize the emerging picture of retinoids in lung cancer through a summary of ongoing investigations in biology, chemoprevention and therapy settings, in an attempt to clarify the possible role of these agents in such a disease. Early work in head and neck cancer has evidenced the capability of retinoids to interrupt field carcinogenesis by reversing premalignant lesions and decreasing the incidence of second primary tumors (SPTs). At this time, the completed randomized trials in lung cancer have failed to demonstrate an evident chemopreventive effect of the tested agents on different study end points, although both a marginally significant benefit of retinol palmitate in time-to-development rates for smoke-related SPTs and a potential preventive effect of retinol supplementation against mesothelioma in selected populations of asbestos-exposed workers have been recently reported. Concerning the role of retinoids in lung cancer treatment, a moderate activity of 13-cis-retinoic acid (13cRA) or all-transretinoic acid (ATRA) as single agents has been reported in small series of advanced, mostly pretreated lung cancer patients. More encouraging findings derive from combination studies, in which retinoids, especially ATRA, are added to either alpha-interferon or chemotherapy and radiotherapy. Major recent advances have been made towards the understanding of retinoids mechanisms of action; at this regard, the role of RAR-beta basal or treatment-induced levels seems to be of particular interest as intermediate end point and/or independent prognostic factor, besides their known importance in lung carcinogenesis. Future research for chemopreventive and therapeutic programs with retinoids in lung cancer should be focused on the investigation of new generation compounds with a specificity for individual retinoid nuclear receptors. Such selective molecules may have a greater activity against lung cancer, with a more favourable toxicity profile, as recently suggested by our preliminary data on Ro 41-5253.

Interferons in dermatology. Present-day standard

Since the first clinical trials in the early 1980s with recombinant interferon, it was possible to show for a variety of indications that cytokines, especially interferons, at certain doses and at respective intervals, when applied in combination with other pharmaceutical compounds open new powerful therapeutic possibilities. Worldwide, recombinant interferon is licensed, especially in dermato-oncology, for the indication of HIV-associated Kaposi's sarcoma, cutaneous T-cell lymphoma, and recently for adjuvant therapy of high-risk malignant melanoma. Recombinant interferon is at present not licensed for dermatologic indication (septic granulomatosis). At the end of our century the indication spectrum for interferons as monotherapy and as combination therapy will undoubtedly be extended. Larger and controlled studies will prove the importance of interferons in dermato-oncology as well as in inflammatory and infectious dermatoses. The combination of interferons with standard therapies will surely be of the utmost importance in dermatotherapy.