Phase II evaluation of interferon added to tamoxifen in the treatment of metastatic breast cancer

Interferon-Stimulated Genes Are Involved in Cross-resistance to Radiotherapy in Tamoxifen-Resistant Breast Cancer

Purpose: Treatment resistance is the main cause of adverse disease outcome in breast cancer patients. Here, we aimed to investigate common features in tamoxifen-resistant and radioresistant breast cancer, as tamoxifen-resistant breast cancer cells are cross-resistant to irradiation in vitroExperimental Design: RNA sequencing of tamoxifen-resistant and radioresistant breast cancer cells was performed and validated by quantitative PCR. Pathways were further investigated in vitro and in breast cancer patient cohorts to establish their relation with treatment resistance.Results: Both tamoxifen-resistant and radioresistant breast cancer cells had increased expression levels of genes involved in type I IFN signaling compared with nonresistant cells. IFN-stimulated genes (ISG) were induced in a dose-dependent and time-dependent manner after tamoxifen treatment and irradiation. Tamoxifen treatment also led to ssDNA presence in the cytoplasm, which is known to induce expression of ISGs, a phenomenon that has already been described for irradiation. Moreover, in a breast cancer patient cohort, high expression levels of ISGs were found in the primary tumor in around half of the patients. This was associated with a tumor-infiltrating lymphocyte (TIL) expression signature, although the ISGs were also expressed by the tumor cells themselves. Importantly, the expression of ISGs correlated with outcome in breast cancer patients treated with adjuvant tamoxifen or radiotherapy, but not in systemically untreated patients or chemotherapy-treated patients.Conclusions: Our data indicate that expression of ISGs by tumor cells is involved in acquired, treatment-induced resistance to tamoxifen and radiotherapy, and might play a role in intrinsic resistance via interaction with TILs. Clin Cancer Res; 24(14); 3397-408. ©2018 AACR.

Antitumour actions of interferons: implications for cancer therapy

The interferons (IFNs) are a family of cytokines that protect against disease by direct effects on target cells and by activating immune responses. The production and actions of IFNs are finely tuned to achieve maximal protection and avoid the potential toxicity associated with excessive responses. IFNs are back in the spotlight owing to mounting evidence that is reshaping how we can exploit this pathway therapeutically. As IFNs can be produced by, and act on, both tumour cells and immune cells, understanding this reciprocal interaction will enable the development of improved single-agent or combination therapies that exploit IFN pathways and new 'omics'-based biomarkers to indicate responsive patients.

A functional in vitro model of heterotypic interactions reveals a role for interferon-positive carcinoma associated fibroblasts in breast cancer

BACKGROUND

Cancer-associated fibroblasts (CAFs) play an important role in breast cancer pathogenesis by paracrine regulation of breast cancer cell biology. Several in vitro and mouse models have characterized the role of cell contact and cytokine molecules mediating this relationship, although few reports have used human CAFs from breast tumors.

METHODS

Primary breast CAF cultures were established and gene expression profiles analysed in order to guide subsequent co-culture models. We used a combination of colorimetric proliferation assays and gene expression profiling to determine the effect of CAFs on the MCF-7 breast cancer cell in an indirect co-culture system.

RESULTS

Using gene expression profiling, we found that a subgroup of breast CAFs are positive for a type one interferon response, confirming previous reports of an activated type one interferon response in whole tumor datasets. Interferon positive breast cancer patients show a poor prognostic outcome in an independent microarray dataset. In addition, CAFs positive for the type one interferon response promoted the growth of the MCF-7 breast cancer cell line in an indirect co-culture model. The addition of a neutralizing antibody against the ligand mediating the type one response in fibroblasts, interferon-β, reverted this co-culture phenotype. CAFs not expressing the interferon response genes also promoted the growth of the MCF-7 breast cancer cell line but this phenotype was independent of the type one fibroblast interferon ligand.

CONCLUSIONS

Primary breast CAFs show inter-patient molecular heterogeneity as evidenced by interferon response gene elements activated in a subgroup of CAFs, which result in paracrine pro-proliferative effects in a breast cancer cell line co-culture model.

Immune manipulation of advanced breast cancer: an interpretative model of the relationship between immune system and tumor cell biology

This review summarizes some recent clinical immunological approaches with cytokines and/or antibodies for therapy of advanced breast cancer. It considers the recent advances in genetics and molecular tumor biology related to impaired immunosurveillance involving cytokines and growth factors to explain clinical results. Evasion of the host immune attack might be induced by the following groups of mechanisms: (a) tumor dependent (genomic instability, HLA class I antigen abnormalities, upregulation of fetal type nonclassical HLA class I molecules, epitope immunodominance, apoptosis inhibition by defective death receptor signaling, apoptosis of activated T cells, tumor cannibalism and constitutive activation of signal transducer, and activator of transcription-3 (Stat 3) and nuclear factor-kappaB (NF-kappaB) signaling); (b) host dependent (CD4+CD25+ regulatory T cells (T reg), CD4+ T cells anergy, Th2 antitumor immunity diversion and myeloid suppressor cells); (c) tumor and host dependent (lack of co-stimulation molecules, immunosuppressive cytokines (vascular endothelial growth factor (VEGF), interleukin (IL)-10, prostaglandin (PG)E2, transforming growth factor (TGF)-beta)). Cytokines and growth factors are involved in virtually all three types of mechanisms. These mechanisms are integrated with the current knowledge of tumor growth and inhibited apoptosis primarily mediated by cytokines and growth factors to propose an interpretation of the relationships among tumor cells, tumor stroma, and tumor-infiltrating lymphocytes. Tumor growth, defective immunorecognition and immunosuppression are the three principal effects considered responsible for immune evasion.

Influence of IFN-gamma and its receptors in human breast cancer

BACKGROUND

Interferons are a group of proteins that trigger multiple responses including prevention of viral replication, inhibition of cell growth, and modulation of cell differentiation. In different mammary carcinoma cell lines IFNgamma induces growth arrest at mid-G1. At the present there are no in vivo studies in human breast. The aim of this study was to investigate the expression patterns of IFNgamma and its two receptors (IFNgamma-Ralpha and IFNgamma-Rbeta) by Western blot and immunohistochemistry, in order to elucidate its role in the different types of human breast cancer (in situ and infiltrative).

METHODS

Immunohistochemical and semiquantitative study of IFNgamma, its receptors types (IFNgamma-Ralpha and IFNgamma-Rbeta), cell proliferation (proliferating cell nuclear antigen, also named PCNA), and apoptosis (TUNEL method) was carried between the three breast groups (fibrocystic lesions, in situ tumors and infiltrating tumors).

RESULTS

In the three groups of patients, IFNgamma and IFNgamma-Ralpha immunoreactions appeared in the cytoplasm while IFNgamma-Rbeta also was found in the nucleus. The optical density to IFNgamma was higher in in situ carcinoma than in benign and infiltrating tumors. When we observed IFNgamma-Ralpha, the optical density was lower in infiltrating carcinoma than in benign and in situ tumors (the higher density). To IFNgamma-Rbeta, the optical density was similar in the three group samples. In tumor samples PCNA and TUNEL index was significantly higher; than in benign diseases. PCNA index increased with the malignance. No significant differences were found between cancer types to TUNEL. IFNgamma could be a potential therapeutic tool in breast cancer. However, tumor cells are able to escape from the control of this cytokine in the early tumor stages; this is probably due to a decreased expression of IFNgamma, or also to an alteration of either its receptors or some transduction elements.

CONCLUSION

We conclude that the decrease in the % positive samples that expressed IFNgamma and IFNgamma-Ralpha together with the nuclear localization of IFNgamma-Rbeta, could be a tumoral cell response, although perhaps insufficient to inhibit the uncontrolled cell proliferation. Perhaps, IFNgamma might be unable to activate p21 to stop the cell cycle, suggesting a possible participation in breast cancer development.

Cytokines in breast cancer

In recent decades many advances have occurred in the understanding of the role of cytokines in breast cancer. New signalling pathways of interleukin (IL)-1 family, IL-6, IL-11, IL-18, interferons (IFNs) and interferon regulatory factors 1 (IRF-1) and 2 (IRF-2) have been found within tumour microenvironments and in metastatic sites. Some cytokines (IL-1, IL-6, IL-11, TGFbeta) stimulate while others (IL-12, IL-18, IFNs) inhibit breast cancer proliferation and/or invasion. Similarly, high circulating levels of some cytokines seem to be favourable (soluble IL-2R) while others are unfavourable (IL-1beta, IL-6, IL-8, IL-10, IL-18, gp130) prognostic indicators. So far IL-2, IFNalpha, IFNbeta and occasionally IFNgamma, IL-6, IL-12 have been the cytokines used for anti tumour treatment of advanced breast cancer either to induce or increase hormone sensitivity and/or to stimulate cellular immunity. Disappointing results occurred in most trials; however, two long-term pilot studies suggest that IL-2 and IFNbeta, when used appropriately can have a positive effect on clinical benefit and overall survival of patients with minimal residual disease after chemotherapy or with disseminated disease controlled by conventional endocrine therapy.

Metastatic breast cancer: an updating

This article reports on recent advances on metastatic breast cancer. Detection, prognostic factors, predictors of response to therapy and therapy, with particular regard to targeted therapies, were examined.

DETECTION

Unlike current guidelines that yet do not routinely recommend intensive clinical-instrumental post-operative follow-up of breast cancer patients, relatively large data collected in the last decades have shown that an intensive post-operative follow-up with 'dynamic evaluation' of a suitable tumour marker panel precedes a few months as average the clinical and/or instrumental sign of a pending relapse in most relapsed patients and largely limits the use of the common instrumental examinations.

PROGNOSIS AND THERAPY PREDICTORS

Disease-free interval (DFI)<or=24 months, adjuvant chemotherapy, liver and distant soft tissue involvement or DFI>24 months and disease confined to bony skeleton are prognostic factors more often correlated with relatively poor or prolonged survival, respectively. Estrogen receptor (ER) expression in primary tumour and at the relapse correlates strongly with response to salvage hormone therapy and data from large trials showed that 38-59% of ER and/or PR+ post-menopausal patients had clinical benefit from first line tamoxifen or aromatase inhibitors. An inverse correlation of ER with epidermal growth factor receptor (EGFR) has been found. The co-expression of HER-2/neu and/or elevated serum HER-2/neu protein level were associated with a low rate and shorter duration of response of ER+ patients to first line hormone therapy. Accordingly, ER-EGFR- compared with ER-EGFR+ tumours are usually more responsive to endocrine therapy. High class III beta-tubulin expression or fall in insulin-like growth factor binding protein-3 (IGFBP-3) from baseline levels have been found to significantly predict resistance to chemotherapeutic agents.

THERAPY

Liposomes as carrier of doxorubicin (Caelix, Evacet, Myocet) is one approach to decrease the anthracycline-related cardiac toxicity. Weekly paclitaxel or docetaxel and oral formulation of vinorelbine and 5-fluorouracil (5-FU) (capecitabine) provide new effective and well tolerated options that reach greater dose intensity and cumulative dose than with the conventional schedules. As to the so called 'tailored' or targeted therapies, the more potent and highly selective third generation of aromatase inhibitors (letrozole, anastrozole, exemestane) targeting ER+ tumours by estrogen deprivation, challenge tamoxifen as current standard first line therapy in postmenopausals. One pilot study showed that stimulation of cellular immunity by the addition of beta-interferon-interleukin-2 sequence in patients on clinical benefit on first line tamoxifen significantly prolonged median overall survival (OS) and duration of response compared to that observed in similar patients only treated with tamoxifen. Trastuzumab, a humanised monoclonal antibody to extracellular domain of HER-2, plus conventional chemotherapy has become a standard of care for women with overexpressing HER-2 tumours. Bevacizumab is a recombinant humanised monoclonal antibody to vascular endothelial growth factor (VEGF) that in refractory metastatic breast cancer doubled the response rate of capecitabine although it did not affect survival. Finally, the so called 'oligometastatic' and a few stage IV diseases are conditions amenable to be rendered with no evidence of disease (NED) after local surgery and/or radiation. In both, as well as in complete responders to chemotherapy, minimal residual disease (m.r.d.) likely continues to be present. Recent data suggest that 'biological' therapy (immunomodulators and/or retinoids with or without hormone therapy), might be suitable to be successfully tested in these patients as maintenance treatment given soon after local intervention or chemotherapy.

Subcutaneously administered recombinant human interleukin-2 and interferon alfa-2a for advanced breast cancer: a phase II study of the Cancer and Leukemia Group B (CALGB 9041)

New and more effective treatments are needed for metastatic breast cancer. This study aimed to determine the effectiveness of a combination of subcutaneously administered recombinant human interleukin-2 (rIL-2), 1.5 MU/m(2) for 5 consecutive days repeated for 3 weeks, and interferon alpha-2a (IFN), 7.5 MU/m(2), administered subcutaneously three times per week. Women who had previously received 1-2 prior chemotherapy regimens for measurable inoperable, recurrent, or metastatic breast cancer were eligible. Of 40 patients accrued to the study, 32 were evaluable for response assessment. Toxicities were frequent but manageable. The most common grade 3 and 4 toxicities were lymphopenia (17%) and malaise/fatigue (24%). There were no complete responses, one partial response (3%), and six patients with stable disease (19%). Of the seven patients with partial response or stable disease, all had tumors that expressed hormone receptors. The median survival was 8.9 months and all patients have died. Good performance status was the most important predictor of survival. In this group of women with metastatic breast cancer, the overall prognosis was poor. This combination of rIL-2 and IFN was ineffective.

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.

Effect of interferon alpha-2a on hormone receptor status in patients with advanced breast cancer

The aim of this study was to assess the effect of recombinant interferon alpha-2a (rh-IFN) on estrogen (ER) and progesterone (PR) receptor expression in patients with advanced breast cancer and the evaluation of the effect of rh-IFN pretreatment on response to endocrine therapy with tamoxifen (TAM). Between June 1990 and November 1992, 20 patients with disseminated breast cancer and with metastatic skin nodules suitable for biopsy were entered into this study. Eighteen assessable patients underwent biopsy before and 2 weeks after treatment with rh-INF. rh-INF 3 x 10(6) IU were administered subcutaneously per day. Patients with ER expression at second biopsy were subsequently treated with 20 mg TAM daily. One patient had rapid disease progression and died before rebiopsy could be performed, and an additional patient refused second biopsy. All other patients were considered assessable. Thirteen patients showed ER expression before rh-IFN treatment, and 5 PR presented with expression. Rh-IFN increased ER expression in three patients and PR in four patients. No change was observed in 8 patients for ER and in 12 patients for PR. ER expression decreased in seven patients and PR expression decreased in two patients, respectively. Two patients showed a partial remission after subsequent treatment with TAM. Adverse reactions caused by rh-IFN were mainly flu-like symptoms. In this trial we found no systematic impact of rh-IFN on hormone receptor expression and, subsequently, on the response rate in patients with advanced breast cancer.

High dose oral tamoxifen and subcutaneous interferon alpha-2a for recurrent glioma

Chemotherapeutic regimens in present use for recurrent glioma have substantial toxicity. Activity against recurrent gliomas has been reported for both tamoxifen and interferon alpha, agents that have more acceptable toxicity profiles and that can be administered in an outpatient setting. We tested the efficacy and toxicity of the combination of high-dose tamoxifen and interferon alpha in adults with recurrent glioma in a phase II trial. Eligible patients had radiographically measurable recurrent gliomas of any grade after initial radiation therapy. Interferon-alpha [6 x 10(6) U subcutaneously three times per week] and tamoxifen (240 mg/m2/day orally) were administered continuously. Treatment response was assessed at 6 week intervals using clinical and radiographic criteria. Eighteen patients (11 males and 7 females) were enrolled. Median age was 41 years (range 23-61 years). All patients had gliomas that progressed after radiation therapy and nitrosourea chemotherapy. The histologic diagnosis of the original tumor was glioblastoma multiforme in 8 patients, anaplastic astrocytoma in 5 patients, astrocytoma in 4 patients and mixed malignant glioma in 1 patient. Reversible moderate to severe neurological toxicity manifested by dizziness and unsteady gait was seen at tamoxifen doses of 240 mg/m2/day. Although the initial tamoxifen dose was reduced to 120 mg/m2/day, moderate neurotoxicity was noted at this dose as well and the trial was closed early. The combination of oral tamoxifen (120 to 240 mg/m2/day) and subcutaneous interferon-alpha [6 x 10(6) U three times per week] was associated with significant neurotoxicity in this group of recurrent glioma patients, resulting in early study closure. Of 16 evaluable patients, 12 had progressive disease after one cycle of treatment, 3 had stable disease, and there was one minor response. Gradual dose escalation may be required if similar patients are to be treated with high dose tamoxifen in conjunction with interferon.

Tamoxifen and interferon-beta for the treatment of metastatic breast cancer

It has been demonstrated, both in breast cancer cell lines and in metastatic breast cancer patients with cutaneous lesions that could be biopsied, that treatment with interferon beta (IFN-B) can increase expression of both estrogen (ER) and progesterone receptors (PgR). To evaluate the efficacy and toxicity of the combination of IFN and tamoxifen, 33 metastatic breast cancer patients were treated with the following regimen: IFN-B, 6.0 million units intramuscularly IU 3 times a week for two consecutive weeks followed by IFN-B 6.0 million IU im 3 times a week with concomitant tamoxifen 20 mg orally daily. Patients were pre and postmenopausal with median age of 60 years, median ECOG PS of 0, either ER positive or unknown, and had not received prior hormone therapy for metastatic disease. Overall objective response was observed in 9 (27%) patients. Complete response was observed in 2 cases and partial response in 7 patients. Median duration of response was 7 months (range 2-10). A higher response rate was observed in patients with predominantly soft tissue disease (38%) compared to patients with either dominant bone (18%) or visceral lesions (17%). Toxicity was mild and reversible: low grade fever in 30% of patients and flu-like symptoms in 9% of cases. It appears that IFN-B does not improve the efficacy of tamoxifen in an unselected population of metastatic breast cancer.

Megestrol acetate plus alpha 2a interferon as second line therapy for postmenopausal patients with advanced breast cancer: results of a multicentric phase II trial

This phase II study was aimed to evaluate the activity of a combination of megestrol acetate (MA) and alpha 2a interferon (IFN) in a group of tamoxifen-responsive breast cancer patients. Thirty patients with metastatic breast cancer either previously treated with adjuvant tamoxifen for at least 24 months or treated with tamoxifen for metastatic disease and showing an objective response or stability of disease, were given MA (single daily dose of 160 mg per os) and alpha 2a IFN (3 million units-MU-three times per week intramuscularly-i.m.-). Of the 29 evaluable patients, 2 (6.8%) achieved a complete response and 4 (13.8%) a partial response for an overall response rate of 20.6% (95% confidence limits = 5.9%-35.4%). Treatment toxicity was mild and no patient had to discontinue or delay the treatment due to IFN side effects. Our results seem to rule out that alpha 2a IFN is able to improve the activity of MA as second-line therapy in tamoxifen-responsive patients.

Interferon plus tamoxifen treatment for advanced breast cancer: in vivo biologic effects of two growth modulators

The effects of interferon-alpha (IFN) plus tamoxifen (TMX) in the treatment of advanced breast cancer were assessed. Changes of in vivo biologic determinants including hormone receptors, P24 protein, Ki-67 and growth factor expression were evaluated. Seven patients with advanced, heavily pretreated, breast cancer with accessible disease, underwent biopsy prior to and after sequential treatment with IFN and IFN plus TMX. Clinically 4/7 patients responded to treatment with one complete and three partial remissions. Apart from the favourable response rate the sequential in vivo changes in expression of tumour variables were of considerable interest. IFN treatment consistently increased the expression of the estrogen receptor (ER) and of the estrogen regulated protein P24 while decreasing the expression of the proliferation associated antigen Ki-67. Addition of TMX on the other hand resulted in a reduction of ER expression to pre-IFN levels and a rise in progesterone receptor (PR) expression. When the effect of either IFN or IFN plus TMX on the expression of two growth factors was assessed they were found to be somewhat variable. While PDGF expression tended to be suppressed, there was no clinical correlation with response to therapy. TGF beta expression was found in all patients prior to treatment and while all non-responders showed reduction of TGF beta following treatment, the alterations were variable amongst responders (including two patients with increased expression, one with no change, and one with decreased expression). It is concluded that both IFN and TMX exert multiple effects on the expression of tumour biologic variables and that while the study confirmed some of the predictions from in vitro models, the in vivo effect are more complex than has been appreciated from the models. From the clinical point of view, it might be expected that treatment which enhances the expression of ER in tumours should have a positive effect on the response to TMX.

Steroid receptor enhancement by natural interferon-beta in advanced breast cancer

In the current study we investigated the effect of two different doses of natural interferon-beta (IFN-beta) on steroid hormone receptors in 45 patients with advanced breast cancer. IFN-beta seems to regulate the receptor mechanisms, inducing in cutaneous metastases an increase of oestrogen and progesterone receptors. Moreover, using IFN-beta and tamoxifen as a combined therapy in 23 receptor-positive patients, no negative interference of the two drugs was observed and no relevant side-effects due to the treatment were noticed. The modulation of steroid receptor content by IFN-beta in advanced breast cancer might represent an interesting way to ameliorate the clinical responsiveness to anti-oestrogens.