Redefining the role of interferon in the treatment of malignant diseases

Update in the Diagnosis and Management of Ocular Surface Squamous Neoplasia (OSSN)

Ocular surface squamous neoplasia (OSSN) includes a variety of ocular surface tumors ranging from mild epithelial dysplasia to invasive squamous cell carcinoma. OSSN is one of the most frequent non-pigmented malignancies of the ocular surface. Debate persists between surgical excision and medical management concerning the optimal regimen for OSSN treatment, with surgical excision continuing to be the recognized standard of care in contemporary medicine. Medical and conservative therapy techniques have advanced significantly in recent years, leading to widespread use in everyday ophthalmology practice. This study aims to look into the efficacy of current treatment options for conjunctival squamous cell carcinoma and to evaluate the available evidence for the most up-to-date approach for the management of the disease.

The underlying mechanism and therapeutic potential of IFNs in viral-associated cancers

Interferons (IFNs) are a diverse family of cytokines secreted by various cells, including immune cells, fibroblasts, and certain viral-parasitic cells. They are classified into three types and encompass 21 subtypes based on their sources and properties. The regulatory functions of IFNs closely involve cell surface receptors and several signal transduction pathways. Initially investigated for their antiviral properties, IFNs have shown promise in combating cancer-associated viruses, making them a potent therapeutic approach. Most IFNs have been identified for their role in inhibiting cancer; however, they have also demonstrated cancer-promoting effects under specific conditions. These mechanisms primarily rely on immune regulation and cytotoxic effects, significantly impacting cancer progression. Despite widespread use of IFN-based therapies in viral-related cancers, ongoing research aims to develop more effective treatments. This review synthesizes the signal transduction pathways and regulatory capabilities of IFNs, highlighting their connections with viruses, cancers, and emerging clinical treatments.

Toll-Like receptor 3-mediated interferon-β production is suppressed by oncostatin m and a broader epithelial-mesenchymal transition program

BACKGROUND

Patients with Triple Negative Breast Cancer (TNBC) currently lack targeted therapies, and consequently face higher mortality rates when compared to patients with other breast cancer subtypes. The tumor microenvironment (TME) cytokine Oncostatin M (OSM) reprograms TNBC cells to a more stem-like/mesenchymal state, conferring aggressive cancer cell properties such as enhanced migration and invasion, increased tumor-initiating capacity, and intrinsic resistance to the current standards of care. In contrast to OSM, Interferon-β (IFN-β) promotes a more differentiated, epithelial cell phenotype in addition to its role as an activator of anti-tumor immunity. Importantly, OSM suppresses the production of IFN-β, although the mechanism of IFN-β suppression has not yet been elucidated.

METHODS

IFN-β production and downstream autocrine signaling were assessed via quantitative real-time PCR (qRT-PCR) and Western blotting in TNBC cells following exposure to OSM. RNA-sequencing (RNA-seq) was used to assess an IFN-β metagene signature, and to assess the expression of innate immune sensors, which are upstream activators of IFN-β. Cell migration was assessed using an in vitro chemotaxis assay. Additionally, TNBC cells were exposed to TGF-β1, Snail, and Zeb1, and IFN-β production and downstream autocrine signaling were assessed via RNA-seq, qRT-PCR, and Western blotting.

RESULTS

Here, we identify the repression of Toll-like Receptor 3 (TLR3), an innate immune sensor, as the key molecular event linking OSM signaling and the repression of IFN-β transcription, production, and autocrine IFN signaling. Moreover, we demonstrate that additional epithelial-mesenchymal transition-inducing factors, such as TGF-β1, Snail, and Zeb1, similarly suppress TLR3-mediated IFN-β production and signaling.

CONCLUSIONS

Our findings provide a novel insight into the regulation of TLR3 and IFN-β production in TNBC cells, which are known indicators of treatment responses to DNA-damaging therapies. Furthermore, strategies to stimulate TLR3 in order to increase IFN-β within the TME may be ineffective in stem-like/mesenchymal cells, as TLR3 is strongly repressed. Rather, we propose that therapies targeting OSM or OSM receptor would reverse the stem-like/mesenchymal program and restore TLR3-mediated IFN-β production within the TME, facilitating improved responses to current therapies.

Medical treatment for ocular surface squamous neoplasia

Ocular surface squamous neoplasia (OSSN) is the most common non-melanocytic tumour of the ocular surface. Surgical excision with wide margins using the "no-touch" method was originally the most popular treatment for OSSN. However, in the past two decades, the use of topical medications for OSSN treatment has gained a reputation amongst ophthalmologists for being an effective alternative to surgical excision. Furthermore, technological advancements, such as those seen in high-resolution optical coherence tomography (HR-OCT) for the anterior segment, have facilitated the diagnosis and monitoring of OSSN. When selecting a topical agent, interferon alpha-2b (IFNα-2b) and 5-fluorouracil (5-FU) are two of the gentlest medications used for OSSN and are often considered first line therapies due to their high-resolution rates and mild side effect profiles. Mitomycin C (MMC), on the other hand, has a highly toxic profile; therefore, while effective, in our hands it is considered as a second-line treatment for OSSN if the other modalities fail. In addition, newer and less studied agents, such as immune checkpoint inhibitors, retinoic acid, aloe vera, and anti-vascular endothelial growth factor have anti-neoplastic properties and have shown potential for the treatment of OSSN. We enclose an updated literature review of medical treatments for OSSN.

The Management of Ocular Surface Squamous Neoplasia (OSSN)

The rise of primary topical monotherapy with chemotherapeutic drugs and immunomodulatory agents represents an increasing recognition of the medical management of ocular surface squamous neoplasia (OSSN), which may replace surgery as the standard of care in the future. Currently, there is no consensus regarding the best way to manage OSSN with no existing guidelines to date. This paper seeks to evaluate evidence surrounding available treatment modalities and proposes an approach to management. The approach will guide ophthalmologists in selecting the most appropriate treatment regime based on patient and disease factors to minimize treatment related morbidity and improve OSSN control. Further work can be done to validate this algorithm and to develop formal guidelines to direct the management of OSSN.

Pegylated Interferon Alpha 2a for the Treatment of Ocular Surface Squamous Neoplasia

PURPOSE

The purpose of this study was to introduce the initial experience in the use of topical pegylated interferon alpha 2a (PegIFN-α-2a) for ocular surface squamous neoplasia (OSSN).

METHODS

A retrospective medical record review of 8 eyes of 8 patients diagnosed with OSSN and treated with PegIFN-α-2a was performed. All cases were diagnosed of noninvasive OSSN both clinically and histologically. The pegIFN-α-2a was prescribed at a concentration of 20 μg/mL and applied 4 times a day for at least 3 months.

RESULTS

In all 8 cases, topical PegIFN-α-2a was well-tolerated and did not lead to discomfort or any adverse side effects. It resulted in reduction in lesion size and extent in all cases and complete resolution of the lesions.

CONCLUSIONS

Topical PegIFN-α-2a might be an effective and safe treatment option for noninvasive OSSN.

Use of interferon alpha 2b to manage conjunctival primary acquired melanosis and conjunctival melanoma

Primary acquired melanosis (PAM) is acquired conjunctival pigmentation that can give rise to conjunctival melanoma (CM), a malignant tumor of the bulbar and palpebral conjunctiva or the caruncle. Surgical excision is the treatment of choice for this neoplasm. Topical chemotherapy is also used for patients with PAM with atypia or CM, hand in patients with recurrent or extensive disease, this may be an important option. Of the several chemotherapeutic drugs used, topical interferon alpha 2b (IFN-α2b) has become popular because of its low toxicity. Clinical evidence from case reports and case series supports the efficacy of IFN-α2b as the preferred adjuvant treatment for PAM and CM. In addition, topical IFN-α2b has been successfully applied to melanocytic tumors refractory to other treatments, such as cryotherapy and topical mitomycin C. In patients with locally advanced CM, the combination of IFN-α2b and systemic immunotherapy may serve as an alternative to exenteration. Given the low frequency of CM, long-term multicenter studies are needed to demonstrate the efficacy of IFN-α2b for preventing local recurrence and distant metastasis.

Mesenchymal stromal cells equipped by IFNα empower T cells with potent anti-tumor immunity

Cancer treatments have been revolutionized by the emergence of immune checkpoint blockade therapies. However, only a minority of patients with various tumor types have benefited from such treatments. New strategies focusing on the immune contexture of the tumor tissue microenvironment hold great promises. Here, we created IFNα-overexpressing mesenchymal stromal cells (IFNα-MSCs). Upon direct injection into tumors, we found that these cells are powerful in eliminating several types of tumors. Interestingly, the intra-tumoral injection of IFNα-MSCs could also induce specific anti-tumor effects on distant tumors. These IFNα-MSCs promoted tumor cells to produce CXCL10, which in turn potentiates the infiltration of CD8⁺ T cells in the tumor site. Furthermore, IFNα-MSCs enhanced the expression of granzyme B (GZMB) in CD8⁺ T cells and invigorated their cytotoxicity in a Stat3-dependent manner. Genetic ablation of Stat3 in CD8⁺ T cells impaired the effect of IFNα-MSCs on GZMB expression. Importantly, the combination of IFNα-MSCs and PD-L1 blockade induced an even stronger anti-tumor immunity. Therefore, IFNα-MSCs represent a novel tumor immunotherapy strategy, especially when combined with PD-L1 blockade.

Mathematical model of STAT signalling pathways in cancer development and optimal control approaches

In various diseases, the STAT family display various cellular controls over various challenges faced by the immune system and cell death programs. In this study, we investigate how an intracellular signalling network (STAT1, STAT3, Bcl-2 and BAX) regulates important cellular states, either anti-apoptosis or apoptosis of cancer cells. We adapt a mathematical framework to illustrate how the signalling network can generate a bi-stability condition so that it will induce either apoptosis or anti-apoptosis status of tumour cells. Then, we use this model to develop several anti-tumour strategies including IFN-β infusion. The roles of JAK-STATs signalling in regulation of the cell death program in cancer cells and tumour growth are poorly understood. The mathematical model unveils the structure and functions of the intracellular signalling and cellular outcomes of the anti-tumour drugs in the presence of IFN-β and JAK stimuli. We identify the best injection order of IFN-β and DDP among many possible combinations, which may suggest better infusion strategies of multiple anti-cancer agents at clinics. We finally use an optimal control theory in order to maximize anti-tumour efficacy and minimize administrative costs. In particular, we minimize tumour volume and maximize the apoptotic potential by minimizing the Bcl-2 concentration and maximizing the BAX level while minimizing total injection amount of both IFN-β and JAK2 inhibitors (DDP).

Review of immune checkpoint inhibitors in immuno-oncology

Tumor cells predominantly express self-antigens and overcoming self-tolerance is the primary challenge to effective immunotherapy. Tumors also express ligands for co-inhibitory molecules on immune cells, in order to suppress anti-tumor immunity. Over a decade ago, the first antibodies generated to block the co-inhibitory molecule CTLA-4 was tested in patients with metastatic melanoma. Results from this landmark trial have informed not only the current landscape of checkpoint blockade but also the way in which immunotherapy trial outcomes are determined. Antibodies targeting PD-1 and its ligand, PD-L1, soon followed and use of these checkpoint inhibitors (ICIs) have expanded exponentially. ICI treatment has shown long-lasting clinical benefit in several tumor types and patients refractory to other treatments can often respond to ICI therapy. On the other hand, in some tumor types, the response to ICI is short-lived and tumors eventually recur. Current clinical trials are focused on enhancing anti-tumor effects through combinations of multiple ICIs with agents which cause tumor death, particularly in solid tumors, in order to enhance antigen presentation. It is also important to define which patients will respond to therapy with ICIs as over half of all patients suffer from immune-related adverse events (irAE), some of which are severe and long-lasting.

The Role of Type I Interferons in the Pathogenesis and Treatment of COVID-19

Type I interferons (IFN-I) were first discovered over 60 years ago in a classical experiment by Isaacs and Lindenman, who showed that IFN-Is possess antiviral activity. Later, it became one of the first approved protein drugs using heterologous protein expression systems, which allowed its large-scale production. It has been approved, and widely used in a pleiotropy of diseases, including multiple-sclerosis, hepatitis B and C, and some forms of cancer. Preliminary clinical data has supported its effectiveness against potential pandemic pathogens such as Ebola and SARS. Still, more efficient and specific drugs have taken its place in treating such diseases. The COVID-19 global pandemic has again lifted the status of IFN-Is to become one of the more promising drug candidates, with initial clinical trials showing promising results in reducing the severity and duration of the disease. Although SARS-CoV-2 inhibits the production of IFNβ and thus obstructs the innate immune response to this virus, it is sensitive to the antiviral activity of externally administrated IFN-Is. In this review I discuss the diverse modes of biological actions of IFN-Is and how these are related to biophysical parameters of IFN-I-receptor interaction and cell-type specificity in light of the large variety of binding affinities of the different IFN-I subtypes towards the common interferon receptor. Furthermore, I discuss how these may guide the optimized use IFN-Is in combatting COVID-19.

Interferons in the Therapy of Severe Coronavirus Infections: A Critical Analysis and Recollection of a Forgotten Therapeutic Regimen with Interferon Beta

The pharmacological and immunological properties of interferons, especially those of interferon beta, and the corresponding treatment strategies are described, and the results of studies with different interferons in coronavirus infections are analysed. Furthermore, the data obtained with high-dosed native interferon beta in life-threatening acute viral diseases as well as the results of clinical pilot studies with high-dosed recombinant interferon beta-1a are provided because they serve as the rationale for the proposed therapeutic regimen to be applied in acute viral infections. This regimen differs from those approved for treatment of multiple sclerosis and consists of interferon beta-1a administered as a 24 hour intravenous infusion at a daily dose of up to 90 µg for 3-5 consecutive days. Since under this regimen transient severe side effects can occur, it is analysed which patients are suitable for this kind of treatment in general and if patients with severe coronavirus infections could also be treated accordingly.

A Dual Role of Type I Interferons in Antitumor Immunity

Type I interferons (IFN-Is) are a family of cytokines that exert direct antiviral effects and regulate innate and adaptive immune responses through direct and indirect mechanisms. It is generally believed that IFN-Is repress tumor development via restricting tumor proliferation and inducing antitumor immune responses. However, recent emerging evidence suggests that IFN-Is play a dual role in antitumor immunity. That is, in the early stage of tumorigenesis, IFN-Is promote the antitumor immune response by enhancing antigen presentation in antigen-presenting cells and activating CD8⁺ T cells. However, in the late stage of tumor progression, persistent expression of IFN-Is induces the expression of immunosuppressive factors (PD-L1, IDO, and IL-10) on the surface of dendritic cells and other bone marrow cells and inhibits their antitumor immunity. This review outlines these dual functions of IFN-Is in antitumor immunity and elucidates the involved mechanisms, as well as their applications in tumor therapy.

Update on pharmacotherapy for ocular surface squamous neoplasia

The most frequently encountered non-pigmented tumor of the ocular surface is ocular surface squamous neoplasia (OSSN). Over the past two decades, the pharmacological management of OSSN has grown, with topical 5-fluorouracil, mitomycin, and interferon alpha 2b all being successfully used to treat this disease. Other agents, such as anti-vascular endothelial growth factor (VEGF), retinoic acid, cidofovir and Aloe vera, have less frequently been used in the treatment of OSSN. This review will discuss these pharmacologic agents, summarizing available data and presenting the approach to the treatment of these tumors.

Distinct Roles of Direct Transduction Versus Exposure to the Tumor Secretome on Murine Endothelial Cells After Melanoma Gene Therapy with Interferon-β and p19Arf

Tumor vasculature plays a central role in tumor progression, making it an attractive therapeutic target. In this study, we explore the antiangiogenic potential of our melanoma gene therapy approach combining interferon β (IFNβ) and p19Arf gene transfer. Since these proteins are modulators of tumor vasculature, we explore the impact of IFNβ and p19Arf gene transfer on murine endothelial cells (tEnd). Adenovirus-mediated gene transfer of p19Arf to tEnd cells inhibited proliferation, tube formation, migration, and led to increased expression of genes related to the p53 cell death pathway, yet IFNβ gene transfer had no significant impact on tEnd viability. Alternatively, tEnd cells were exposed to the factors generated by transduced B16 (mouse melanoma) cells using either coculture or conditioned medium. In either case, transduction of B16 cells with the IFNβ vector, whether alone or in combination with p19Arf, resulted in endothelial cell death. Strikingly, treatment of tEnd cells with recombinant IFNβ did not induce death, demonstrating that additional factors produced by B16 cells contributed to the demise of tEnd cells. In this work, we have shown that our melanoma gene therapy strategy produces desirable negative effects on endothelial cells, possibly correlating with antiangiogenic activity.

Role of tumor-associated neutrophils in regulation of tumor growth in lung cancer development: A mathematical model

Neutrophils display rapid and potent innate immune responses in various diseases. Tumor-associated neutrophils (TANs) however either induce or overcome immunosuppressive functions of the tumor microenvironment through complex tumor-stroma crosstalk. We developed a mathematical model to address the question of how phenotypic alterations between tumor suppressive N1 TANS, and tumor promoting N2 TANs affect nonlinear tumor growth in a complex tumor microenvironment. The model provides a visual display of the complex behavior of populations of TANs and tumors in response to various TGF-β and IFN-β stimuli. In addition, the effect of anti-tumor drug administration is incorporated in the model in an effort to achieve optimal anti-tumor efficacy. The simulation results from the mathematical model were in good agreement with experimental data. We found that the N2-to-N1 ratio (N21R) index is positively correlated with aggressive tumor growth, suggesting that this may be a good prognostic factor. We also found that the antitumor efficacy increases when the relative ratio (Dap) of delayed apoptotic cell death of N1 and N2 TANs is either very small or relatively large, providing a basis for therapeutically targeting prometastatic N2 TANs.

Clinical Management of Ocular Surface Squamous Neoplasia: A Review of the Current Evidence

Ocular surface squamous neoplasia (OSSN) is the most common non-pigmented malignancy of the ocular surface and is represented in a wide range of histologic diagnoses, ranging from mild epithelial dysplasia to invasive squamous carcinoma. Although surgical excision is still the gold standard for OSSN treatment, interest in conservative medical approaches is steadily growing. We have reviewed all of the literature on OSSN published in English in the MEDLINE database up to May 2018, using the keywords “ocular surface squamous neoplasia,” “squamous conjunctival carcinoma,” and “conjunctival carcinoma in situ,” with the aim to provide a comprehensive review of the most recent evidence on this distinct clinical entity.

Crosstalk between type I and II interferons in regulation of myeloid cell responses during bacterial infection

Type I and type II interferons (IFNα/β and IFNγ) are cytokines that play indispensable roles in directing myeloid cell activity during inflammatory and immune responses. Each IFN type binds a distinct receptor (IFNAR or IFNGR) to transduce signals that reshape gene expression and function of myeloid and other cell types. In the context of murine models and human bacterial infections, production of IFNγ generally promotes resistance while production of IFNα/β is associated with increased host susceptibility. Here, we review mechanisms of crosstalk between type I and II IFNs in myeloid cells and their impact on myeloid cell activation and anti-microbial function.

Autocrine activation of the IFN signaling pathway may promote immune escape in glioblastoma

BACKGROUND

Interferons (IFNs) are cytokines typically induced upon viral infection but are constitutively expressed also in the absence of acute infection. The physiological role of autocrine and paracrine IFN signaling, however, remains poorly understood, and its function in glioblastoma has not been explored in depth.

METHODS

Using RNA interference-mediated gene silencing, we characterized constitutive type I IFN signaling and its role in human glioma cells.

RESULTS

We observed constitutive expression of phosphorylated signal transducer and activator of transcription 1 (pSTAT1) and myxovirus resistance protein A (MxA), a classical IFN-response marker, in the absence of exogenous IFN-β. In vivo, we found higher MxA expression in gliomas than in normal tissue, suggesting that IFN signaling is constitutively active in these tumors. To demonstrate the presence of an autocrine type I IFN signaling loop in glioma cells in vitro, we first confirmed the expression of the type I alpha/beta receptor (IFNAR)1/2, and its ligands, IFN-α and IFN-β. Small interfering RNA-mediated receptor gene silencing resulted in reduced expression of MxA at mRNA and protein levels, as did gene silencing of the ligands, corroborating the hypothesis of an autocrine signaling loop in which type I IFNs induce intracellular signaling through IFNAR1/2. On a functional level, following IFNAR1 or IFNAR2 gene silencing, we observed reduced programmed death ligand 1 (PD-L1) and major histocompatibility complex (MHC) class I and II expression as well as an enhanced susceptibility to natural killer immune cell lysis, suggesting that autocrine IFN signaling contributes to the immune evasion of glioma cells.

CONCLUSIONS

Our findings point to an important role of constitutive IFN signaling in glioma cells by modulating their interaction with the microenvironment.

Immunoreduction of ocular surface tumours with intralesional interferon alpha-2a

PurposeTo share our initial experience in the use of intralesional interferon alpha-2a at primary presentation in ocular surface tumours as a method of immunoreduction prior to definitive surgical management.MethodsCase series of patients referred to Sheffield Ocular Oncology Service with rapidly growing ocular surface tumours, treated with intralesional interferon alpha-2a at first presentation prior to definitive surgical management.ResultsAll three patients, two with conjunctival melanoma and one with ocular surface squamous neoplasia (OSSN) demonstrated immunoreduction of tumour without any adverse side effects.ConclusionsInterferon alpha-2a is effective in conjunctival melanoma and OSSN. Intralesional interferon at first presentation may be used for immunoreduction prior to definitive surgical management. This may improve surgical and long-term outcomes, improve patient experience, and help meet cancer treatment targets.

Dacryoendoscopy-guided transcanalicular intralesional interferon alpha 2b for canalicular squamous papillomas

Canalicular papillomatosis is a rare disorder characterized by a mass lesion arising from the epithelium as a stalk from one of the canalicular walls. Traditionally, they have been treated with an open canaliculotomy and excision biopsy with or without additional cryotherapy. A patient with upper canalicular squamous papillomas treated with dacryoendoscopy-guided transcanalicular intralesional and topical interferon alpha 2b is presented, and the ineffectiveness of interferons in this case is discussed.

A Potent In Vivo Antitumor Efficacy of Novel Recombinant Type I Interferon

Purpose: Antiproliferative, antiviral, and immunomodulatory activities of endogenous type I IFNs (IFN1) prompt the design of recombinant IFN1 for therapeutic purposes. However, most of the designed IFNs exhibited suboptimal therapeutic efficacies against solid tumors. Here, we report evaluation of the in vitro and in vivo antitumorigenic activities of a novel recombinant IFN termed sIFN-I.Experimental Design: We compared primary and tertiary structures of sIFN-I with its parental human IFNα-2b, as well as affinities of these ligands for IFN1 receptor chains and pharmacokinetics. These IFN1 species were also compared for their ability to induce JAK-STAT signaling and expression of the IFN1-stimulated genes and to elicit antitumorigenic effects. Effects of sIFN-I on tumor angiogenesis and immune infiltration were also tested in transplanted and genetically engineered immunocompetent mouse models.Results: sIFN-I displayed greater affinity for IFNAR1 (over IFNAR2) chain of the IFN1 receptor and elicited a greater extent of IFN1 signaling and expression of IFN-inducible genes in human cells. Unlike IFNα-2b, sIFN-I induced JAK-STAT signaling in mouse cells and exhibited an extended half-life in mice. Treatment with sIFN-I inhibited intratumoral angiogenesis, increased CD8+ T-cell infiltration, and robustly suppressed growth of transplantable and genetically engineered tumors in immunodeficient and immunocompetent mice.Conclusions: These findings define sIFN-I as a novel recombinant IFN1 with potent preclinical antitumorigenic effects against solid tumor, thereby prompting the assessment of sIFN-I clinical efficacy in humans. Clin Cancer Res; 23(8); 2038-49. ©2016 AACR.

[T-peptide Enhances the Killing Effects of Cisplatinum on Lung Cancer]

背景与目的

T肽是Tuftsin的衍生物，其基本功能是刺激巨噬细胞，提高巨噬细胞吞噬及分泌能力，通过增强效应细胞的细胞杀伤作用而被广泛用于多种恶性肿瘤术后抗肿瘤治疗。本研究旨在探讨T肽与化疗药物顺铂的联合能否提高铂类药物的抗肿瘤疗效及机制。

方法

应用酶联免疫吸附剂测定（enzyme-linked immunosorbent assay, ELISA）T肽和/或顺铂处理人巨噬细胞株U937后肿瘤坏死因子-α（tumor necrosis factor-α, TNF-α）和干扰素-γ（interferon-γ, IFN-γ）分泌水平的变化；应用裸鼠荷瘤动物模型，分析T肽和/或顺铂处理小鼠肿瘤变化情况以及小鼠用药期间外周血中巨噬细胞变化情况。

结果

①应用ELISA检测发现在T肽组和T肽联合顺铂组中，U937细胞培养液中TNF-α水平明显高于对照组和顺铂组；T肽联合顺铂组中IFN-γ水平明显高于对照组、顺铂组和T肽组；②在小鼠荷瘤模型中，T肽联合顺铂组的肿瘤体积明显小于对照组、顺铂组和T肽组，并且小鼠没有明显的体重下降；③在小鼠外周血的检测分析中发现，T肽联合顺铂组中活化巨噬细胞数呈现增长趋势。免疫组化分析各组中肿瘤组织Ki67显示T肽联合顺铂组抑制肿瘤细胞增殖。

结论

T肽能够促进巨噬细胞增殖和促进其分泌肿瘤细胞杀伤因子（TNF-α、IFN-γ）；在体内动物模型中，T肽能够提高化疗药物如顺铂的疗效，使联合组具有更强的肿瘤抑制作用，同时能够减轻化疗药物的毒副作用。

Anti-HBV drugs suppress the growth of HBV-related hepatoma cells via down-regulation of hepatitis B virus X protein

Chronic infection of hepatitis B virus (HBV) is closely associated with the development of hepatocellular carcinoma (HCC). Meta-analyses show that adjuvant anti-HBV therapy is effective for HBV-related HCC patients in clinical. However, the significance that anti-HBV drugs depress HCC is poorly understood. Here, we investigated the effects of telbivudine (LdT), entecavir (ETV) and interferon-α2b (IFN-α2b) on HBV-related HCC. Our data showed that the treatment with the drugs significantly suppressed the growth of HBV-expressing hepatoma cells in vitro and in vivo, but failed to work in HBV-free liver cells. We present the hypothesis that HBx may be involved in the event. As expected, we observed that the expression of HBx was down-regulated by the agents. Meanwhile, the expression of HBx downstream factors was significantly down-regulated. Interestingly, LdT, ETV and IFN-α2b lost the anti-proliferation effects on HBV-related hepatoma cells when the cells were treated with HBx siRNA. Moreover, combination of those drugs enhanced the anti-proliferation effects. In conclusion, LdT, ETV and IFN-α2b suppress the growth of HBV-related HCC through down-regulation of HBx. Our finding provides new insights into the mechanisms of anti-HBV drugs in HCC therapy.

Diagnosis and Medical Management of Ocular Surface Squamous Neoplasia

INTRODUCTION

Topical chemotherapy has gained popularity among clinicians for the treatment of ocular surface squamous neoplasia (OSSN). The principal topical chemotherapy agents used in the management of OSSN are interferon-α2b, 5-fluorouracil, and mitomycin C. High-resolution optical coherence tomography (HR-OCT) is a non-invasive technique that can differentiate OSSN from other ocular surface lesions.

AREAS COVERED

This review highlights the current regimens and diagnostic modalities used in managing OSSN. A review of the literature was performed using the keywords "conjunctival intraepithelial neoplasia", "ocular surface squamous neoplasia", "optical coherence tomography", "interferon-α2b", "5-fluorouracil" and "mitomycin C".

EXPERT COMMENTARY

Topical chemotherapy for OSSN can be used as primary therapy, for chemoreduction prior to surgical excision, and postoperatively to prevent tumor recurrence. It has the advantage of treating microscopic disease as well as large tumors. HR-OCT provides an "optical biopsy" that can assist in diagnosis and guide management of OSSN lesions.

Intratumoral Immunization by p19Arf and Interferon-β Gene Transfer in a Heterotopic Mouse Model of Lung Carcinoma

Therapeutic strategies that act by eliciting and enhancing antitumor immunity have been clinically validated as an effective treatment modality but may benefit from the induction of both cell death and immune activation as primary stimuli. Using our AdRGD-PG adenovector platform, we show here for the first time that in situ gene transfer of p19Arf and interferon-β (IFNβ) in the LLC1 mouse model of lung carcinoma acts as an immunotherapy. Although p19Arf is sufficient to induce cell death, only its pairing with IFNβ significantly induced markers of immunogenic cell death. In situ gene therapy with IFNβ, either alone or in combination with p19Arf, could retard tumor progression, but only the combined treatment was associated with a protective immune response. Specifically in the case of combined intratumoral gene transfer, we identified 167 differentially expressed genes when using microarray to evaluate tumors that were treated in vivo and confirmed the activation of CCL3, CXCL3, IL1α, IL1β, CD274, and OSM, involved in immune response and chemotaxis. Histologic evaluation revealed significant tumor infiltration by neutrophils, whereas functional depletion of granulocytes ablated the antitumor effect of our approach. The association of in situ gene therapy with cisplatin resulted in synergistic elimination of tumor progression. In all, in situ gene transfer with p19Arf and IFNβ acts as an immunotherapy involving recruitment of neutrophils, a desirable but previously untested outcome, and this approach may be allied with chemotherapy, thus providing significant antitumor activity and warranting further development for the treatment of lung carcinoma.

Peginterferon Beta-1a Shows Antitumor Activity as a Single Agent and Enhances Efficacy of Standard of Care Cancer Therapeutics in Human Melanoma, Breast, Renal, and Colon Xenograft Models

Because of its tumor-suppressive effect, interferon-based therapy has been used for the treatment of melanoma. However, limited data are available regarding the antitumor effects of pegylated interferons, either alone or in combination with approved anticancer drugs. We report that treatment of human WM-266-4 melanoma cells with peginterferon beta-1a induced apoptotic markers. Additionally, peginterferon beta-1a significantly inhibited the growth of human SK-MEL-1, A-375, and WM-266-4 melanoma xenografts established in immunocompromised mice. Peginterferon beta-1a regressed large, established WM-266-4 xenografts in nude mice. Treatment of SK-MEL-1 tumor-bearing mice with a combination of peginterferon beta-1a and the MEK inhibitor PD325901 ((R)-N-(2,3-dihydroxypropoxy)-3,4-difluoro-2-(2-fluoro-4-iodophenylamino)benzamide) significantly improved tumor growth inhibition compared with either agent alone. Examination of the antitumor activity of peginterferon beta-1a in combination with approved anticancer drugs in breast and renal carcinomas revealed improved antitumor activity in these preclinical xenograft models, as did the combination of peginterferon beta-1a and bevacizumab in a colon carcinoma xenograft model.

Topical 5-Fluorouracil 1% as Primary Treatment for Ocular Surface Squamous Neoplasia

PURPOSE

To determine the efficacy of topical 5-fluorouracil 1% (5-FU) as a primary treatment of ocular surface squamous neoplasia (OSSN).

DESIGN

Retrospective study.

PARTICIPANTS

Topical 5-FU was used as primary therapy in 44 patients with OSSN.

METHODS

5-Fluorouracil 1% administered topically 4 times daily for 1 week followed by a drug holiday of 3 weeks. Patients were identified through a pharmacy database. Patients were excluded if 5-FU was used as adjuvant therapy, if they did not complete therapy, or if they were still actively receiving treatment for OSSN at the time of last follow-up.

MAIN OUTCOME MEASURES

The primary outcome measures were the frequency of complete resolution with topical 5-FU treatment and the rate of OSSN recurrence.

RESULTS

Of the 44 patients identified, 32 were men and 12 were women. The mean age was 68 years. Complete resolution of OSSN was noted in 82% of patients (36/44); 18% (8/44) were considered treatment nonresponders. Patients were treated with a median of 4 cycles (range, 2-9 cycles). Nasal location was the only risk factor identified for nonresponse to therapy (P = 0.04). The median follow-up after resolution was 10 months (range, 2-77 months). In the 36 patients who showed complete resolution, 4 experienced tumor recurrence. Recurrence rates at 1 and 2 years were 6% and 15%, respectively, using Kaplan-Meier survival analysis. At least 1 side effect from the medication was reported by 61% of patients (21/44), but only 1 patient discontinued the medication because of intolerance. The most common side effect was pain (n = 17; 39%), followed by tearing (n = 10; 23%), photophobia (n = 6; 14%), itching (n = 4; 9%), swelling (n = 2; 5%), and infection (n = 1; 2%). No long-term complications were reported.

CONCLUSIONS

5-Fluorouracil is effective and well tolerated as a primary treatment for OSSN, with 82% of tumors responding completely to therapy.

Effects of sorafenib combined with low-dose interferon therapy for advanced hepatocellular carcinoma: a pilot study

BACKGROUND

Sorafenib is a standard of care for advanced hepatocellular carcinoma (HCC). An in vitro study showed the synergistic effects of sorafenib and interferon for HCC. To clarify the efficacy, combination therapy with sorafenib and interferon was performed for patients with advanced HCC.

METHODS

Pegylated interferon α-2a was administered every 2 weeks for the initial 4 weeks. Subsequently, it was combined with sorafenib. We evaluated the anti-tumor effect and biomarkers during treatment period.

RESULTS

The subjects were 13 patients with advanced HCC complicated by hepatitis C virus (HCV)-related liver cirrhosis. A partial response, stable disease and progressive disease were noted in 4, 6, and 3 patients, respectively. The response rate, the disease control rate, the mean time to progression and the median survival time (MST) were 30.8 % (4/13), 76.9 % (10/13), 12.2 months, and 17.5 months, respectively. In 8 Child-Pugh class A and 5 Child-Pugh class B patients, the MST was 22.0 and 11.0 months, respectively (p = 0.001). In plasma vascular endothelial growth factor (VEGF), serum alpha-fetoprotein (AFP), AFP-L3, a protein induced by vitamin K absence or antagonist-II (PIVKA II), and hepatocyte growth factor (HGF), there was no pretreatment factor and no biomarker during the combination therapy to predict therapeutic effect in the present study.

CONCLUSIONS

The results of this study suggest that combination therapy with sorafenib and interferon could be effective and safe in advanced HCC patients with HCV-related liver cirrhosis.

IFN-β affects the angiogenic potential of circulating angiogenic cells by activating calpain 1

Circulating angiogenic cells (CACs) are monocyte-derived cells with endothelial characteristics, which contribute to both angiogenesis and arteriogenesis in a paracrine way. Interferon-β (IFN-β) is known to inhibit these divergent processes in animals and patients. We hypothesized that IFN-β might act by affecting the differentiation and function of CACs. CACs were cultured from peripheral blood mononuclear cells and phenotypically characterized by surface expression of monocytic and endothelial markers. IFN-β significantly reduced the number of CACs by 18–64%. Apoptosis was not induced by IFN-β, neither in mononuclear cells during differentiation, nor after maturation to CACs. Rather, IFN-β impaired adhesion to, and spreading on, fibronectin, which was dependent on α5β1 (VLA-5)-integrin. IFN-β affected the function of VLA-5 in mature CACs, leading to rounding and detachment of cells, by induction of calpain 1 activity. Cell rounding and detachment was completely reversed by inhibition of calpain 1 activity in mature CACs. During in vitro capillary formation, CAC addition and calpain 1 inhibition enhanced sprouting of endothelial cells to a comparable extent, but were not sufficient to rescue tube formation in the presence of IFN-β. We show that the IFN-β-induced reduction of the numbers of in vitro differentiated CACs is based on activation of calpain 1, resulting in an attenuated adhesion to extracellular matrix proteins via VLA-5. In vivo, this could lead to inhibition of vessel formation due to reduction of the locally recruited CAC numbers and their paracrine angiogenic factors.

High efficiency cell-specific targeting of cytokine activity

Systemic toxicity currently prevents exploiting the huge potential of many cytokines for medical applications. Here we present a novel strategy to engineer immunocytokines with very high targeting efficacies. The method lies in the use of mutants of toxic cytokines that markedly reduce their receptor-binding affinities, and that are thus rendered essentially inactive. Upon fusion to nanobodies specifically binding to marker proteins, activity of these cytokines is selectively restored for cell populations expressing this marker. This 'activity-by-targeting' concept was validated for type I interferons and leptin. In the case of interferon, activity can be directed to target cells in vitro and to selected cell populations in mice, with up to 1,000-fold increased specific activity. This targeting strategy holds promise to revitalize the clinical potential of many cytokines.

STAT3 Single Nucleotide Polymorphism rs4796793 SNP Does Not Correlate with Response to Adjuvant IFNα Therapy in Stage III Melanoma Patients

Interferon alpha (IFNα) is approved for adjuvant treatment of stage III melanoma in Europe and the US. Its clinical efficacy, however, is restricted to a subpopulation of patients while side effects occur in most of treated patients. Thus, the identification of predictive biomarkers would be highly beneficial to improve the benefit to risk ratio. In this regard, STAT3 is important for signaling of the IFNα receptor. Moreover, the STAT3 single-nucleotide polymorphism (SNP) rs4796793 has recently been reported to be associated with IFNα sensitivity in metastatic renal cell carcinoma. To translate this notion to melanoma, we scrutinized the impact of rs4796793 functionally and clinically in this cancer. Interestingly, melanoma cells carrying the minor allele of rs4796793 were the most sensitive to IFNα in vitro. However, we did not detect a correlation between SNP genotype and STAT3 mRNA expression for either melanoma cells or for peripheral blood lymphocytes. Next, we analyzed the impact of rs4796793 on the clinical outcome of 259 stage III melanoma patients of which one-third had received adjuvant IFNα treatment. These analyses did not reveal a significant association between the STAT3 rs4796793 SNP and patients’ progression free or overall survival when IFNα treated and untreated patients were compared. In conclusion, STAT3 rs4796793 SNP is no predictive marker for the efficacy of adjuvant IFNα treatment in melanoma patients.

The clinicopathological and gene expression patterns associated with ulceration of primary melanoma

Ulceration of primary melanomas is associated with poor prognosis yet is reported to predict benefit from adjuvant interferon. To better understand the biological processes involved, clinicopathological factors associated with ulceration were determined in 1804 patients. From this cohort, 348 primary tumor blocks were sampled to generate gene expression data using a 502-gene cancer panel and 195 blocks were used for immunohistochemistry to detect macrophage infiltration and vessel density. Gene expression results were validated using a whole genome array in two independent sample sets. Ulceration of primary melanomas was associated with more proliferative tumors, tumor vessel invasion, and increased microvessel density. Infiltration of tumors with greater number of macrophages and gene expression pathways associated with wound healing and up-regulation of pro-inflammatory cytokines suggests that ulceration is associated with tumor-related inflammation. The relative benefit from interferon reported in patients with ulcerated tumors may reflect modification of signaling pathways involved in inflammation.

Type I Interferon Receptor Expression in Human Pancreatic and Periampullary Cancer Tissue

OBJECTIVES

Interferons (IFNs) have several anticancer mechanisms. A number of clinical trials have been conducted regarding adjuvant IFN-α therapy in pancreatic cancer. Type I IFNs exert their effect via the type I IFN receptor (IFNAR-1, IFNAR-2c). The aims of the present study were to determine the type I IFN receptor expression in pancreatic and periampullary cancer tissues and to study its relation with clinicopathological factors.

METHODS

Receptor expression was determined by immunohistochemistry in paraffin-embedded cancer tissue of 47 pancreatic and 54 periampullary cancer patients.

RESULTS

The results demonstrated that 91.5% of the pancreatic tumors and 88.9% of the periampullary tumors showed expression of IFNAR-1, of which 23.4% and 13.0% were strongly positive, respectively. Regarding IFNAR-2c expression, 68.1% of the pancreatic tumors and 68.5% of the periampullary tumors were positive, of which 4.3% of the pancreatic tumors and none of the periampullary tumors had a strong expression. No statistically significant associations were found between type I IFN receptor expression and clinicopathological factors or survival.

CONCLUSIONS

Type I IFN receptors are expressed in pancreatic and periampullary cancer tissues although with great intertumoral and intratumoral variability. A small proportion of both tumors showed a strong expression of the IFNAR-1; only a very small percentage of the pancreatic tumors showed strong expression of the IFNAR-2c.

Potentials of interferon therapy in the treatment of pancreatic cancer

Pancreatic cancer is a highly aggressive malignancy with limited treatment options. To improve survival for patients with pancreatic cancer, research has focused on other treatment modalities like adding biological modulators such as type-I interferons (IFNs). Type I IFNs (ie, IFN-α/IFN-β) have antiproliferative, antiviral, and immunoregulatory activities. Furthermore, they are able to induce apoptosis, exert cell cycle blocking, and sensitize tumor cells for chemo- and radiotherapy. A few years ago in vitro, in vivo, and several clinical trials have been described regarding adjuvant IFN-α therapy in the treatment of pancreatic cancer. Some studies reported a remarkable increase in the 2- and 5-year survival. Unfortunately, the only randomized clinical trial did not show a significant increase in overall survival, although the increased median survival implicated that some patients in the experimental group benefited from the adjuvant IFN-α therapy. Furthermore, encouraging in vitro and in vivo data points to a possible role for adjuvant IFN therapy. However, up till now, the use of IFNs in the treatment of pancreatic cancer remains controversial. This review, therefore, aims to describe, based on the available data, whether there is a distinct role for IFN therapy in the treatment of pancreatic cancer.

Measles Edmonston vaccine strain derivatives have potent oncolytic activity against osteosarcoma

Osteosarcoma (OS) is the most common primary bone tumor affecting children and young adults, and development of metastatic disease is associated with poor prognosis. The purpose of this study was to evaluate the antitumor efficacy of virotherapy with engineered measles virus (MV) vaccine strains in the treatment of OS. Cell lines derived from pediatric patients with OS (HOS, MG63, 143B, KHOS-312H, U2-OS and SJSA1) were infected with MV expressing green fluorescent protein (MV-GFP) and MV-expressing sodium iodide symporter (MV-NIS) strains. Viral gene expression and cytotoxicity as defined by syncytial formation, cell death and eradication of cell monolayers were demonstrated. Findings were correlated with in vivo efficacy in subcutaneous, orthotopic (tibial bone) and lung metastatic OS xenografts treated with the MV derivative MV-NIS via the intratumoral or intravenous route. Following treatment, we observed decrease in tumor growth of subcutaneous xenografts (P=0.0374) and prolongation of survival in mice with orthotopic (P<0.0001) and pulmonary metastatic OS tumors (P=0.0207). Expression of the NIS transgene in MV-NIS infected tumors allowed for single photon emission computed tomography and positron emission tomography-computed tomography imaging of virus infected tumors in vivo. Our data support the translational potential of MV-based virotherapy approaches in the treatment of recurrent and metastatic OS.

Type I interferons in bacterial infections: taming of myeloid cells and possible implications for autoimmunity

Type I interferons (IFNs) were first described for their ability to protect the host from viral infections and may also have beneficial effects under specific conditions within some bacterial infections. Yet, these pleiotropic cytokines are now known to exacerbate infections by numerous life-threatening bacteria, including the intracellular pathogens Listeria monocytogenes and Mycobacterium tuberculosis. The evidence that such detrimental effects occur during bacterial infections in both animals and humans argues for selective pressure. In this review, we summarize the evidence demonstrating a pro-bacterial role for type I IFNs and discuss possible mechanisms that have been proposed to explain such effects. The theme emerges that type I IFNs act to suppress myeloid cell immune responses. The evolutionary conservation of such anti-inflammatory effects, particularly in the context of infections, suggests they may be important for limiting chronic inflammation. Given the effectiveness of type I IFNs in treatment of certain autoimmune diseases, their production may also act to raise the threshold for activation of immune responses to self-antigens.

Critical roles for Rictor/Sin1 complexes in interferon-dependent gene transcription and generation of antiproliferative responses

We provide evidence that type I IFN-induced STAT activation is diminished in cells with targeted disruption of the Rictor gene, whose protein product is a key element of mTOR complex 2. Our studies show that transient or stable knockdown of Rictor or Sin1 results in defects in activation of elements of the STAT pathway and reduced STAT-DNA binding complexes. This leads to decreased expression of several IFN-inducible genes that mediate important biological functions. Our studies also demonstrate that Rictor and Sin1 play essential roles in the generation of the suppressive effects of IFNα on malignant erythroid precursors from patients with myeloproliferative neoplasms. Altogether, these findings provide evidence for critical functions for Rictor/Sin1 complexes in type I IFN signaling and the generation of type I IFN antineoplastic responses.

Novaferon, a novel recombinant protein produced by DNA-shuffling of IFN-α, shows antitumor effect in vitro and in vivo

Objective

A recombinant antitumor/antiviral protein (Novaferon, Nova) is a new type of interferon, which is produced by artificial design technology combining DNA-shuffling and High Throughput Screening (HTS).

Methods

The in vitro biological activities, such as anti-tumor activity and antiviral activity of Nova and recombinant human interferon alpha-2b (rhIFN-α2b) was performed; in vivo anti-tumor activity in nude mice was also tested. Flow cytometry, histo-pathological analysis including HE staining and immunohistochemistry, and surface plasmon resonance assay were performed to investigate the underlying mechanisms analysis.

Results

Nova exhibited stronger anti-cancer effects compared to rhIFN-α2b in vitro and in vivo. The antitumor mechanisms of Nova may be related to S phase arrest, pro-apoptosis, and inhibition of tumor angiogenesis. Moreover, Nova exhibited a higher binding affinity for IFN receptor 2 (IFNR2) than rhIFN-α2b, which is one of the possible reasons accounting for its stronger actions against tumor cells compared with rhIFN-α2b.

Conclusion

Nova has strong antitumor activity and could be a potentially effective therapeutic drug for cancer.

Surgical versus medical treatment of ocular surface squamous neoplasia: a comparison of recurrences and complications

PURPOSE

Treatment for ocular surface squamous neoplasia (OSSN) has historically been surgery, but nonsurgical interventions are increasingly used. Treatment with interferon is efficacious, but evidence is needed regarding recurrence and complication rates in comparison with surgery. The objective of this study is to compare the recurrence and complication rates of surgical treatment and interferon treatment for OSSN.

DESIGN

A matched, case-control study.

PARTICIPANTS

Ninety-eight patients with OSSN, 49 of whom were treated with interferon (IFN) α2b therapy and 49 of whom were treated with surgical intervention.

METHODS

Patients with OSSN were treated with surgery versus IFNα2b therapy, either in topical or injection form. Median follow-up after lesion resolution was 21 months (range, 0-173 months) for the IFNα2b group and 24 months (range, 0.9-108 months) for the surgery group.

MAIN OUTCOME MEASURES

The primary outcome measure for the study was the rate of recurrence of OSSN in each of the treatment groups. Recurrence rates were evaluated using Kaplan-Meier survival analysis.

RESULTS

Mean patient age and sex were similar between the groups. There was a trend toward higher clinical American Joint Committee on Cancer tumor grade in the IFNα2b group. Despite this, the number of recurrences was equal at 3 per group. The 1-year recurrence rate was 5% in the surgery group versus 3% in the IFNα2b group (P = 0.80). There was no statistically significant difference in the recurrence rate between the surgically and medically treated groups. Nonlimbal location was a risk factor for recurrence (hazard ratio, 8.96) in the entire study population. In patients who were treated successfully, the side effects of the 2 treatments were similar, with mild discomfort seen in the majority of patients in both groups. There was no limbal stem cell deficiency, symblepharon, or diplopia noted in either group. Two patients were excluded from the IFNα2b group because of intolerance to the medication.

CONCLUSIONS

No difference in the recurrence rate of OSSN was found between surgical versus IFNα2b therapy.

Interferon-α-secreting mesenchymal stem cells exert potent antitumor effect in vivo

Mesenchymal stem cells (MSCs) are a kind of adult stem cells that can be isolated easily from bone marrow, adipose tissue, umbilical cord and many other tissues. MSCs have been shown to specifically migrate to inflammatory sites, including tumors, and hold great promise as tumor-specific vectors to deliver antitumor agents. Interferon-α (IFNα) has been used in clinic to treat various types of tumors; however, because of its short half-life, significant therapeutic effects require high doses that often results in serious side effects. Here, we tested whether MSCs continuingly secreting IFNα can exert a persistent antitumor effect and eliminate the side effects associated with high clinical doses of recombinant IFNα. We found that even a small number of IFNα-secreting MSCs could potently halt B16 tumor growth in vivo. The antitumor activity of IFNα-secreting MSCs was largely abolished in immunodeficient mice, an effect largely attributed to natural killer cells and CD8(+) T cells. Therefore, IFNα-secreting MSCs provide an innovative strategy for tumor therapy.

Expression and regulatory effects of murine Schlafen (Slfn) genes in malignant melanoma and renal cell carcinoma

There is emerging evidence that the IFN-inducible family of Slfn genes and proteins play important roles in cell cycle progression and control of cellular proliferation, but the precise functional roles of different Slfn members in the regulation of tumorigenesis remain unclear. In the present study, we undertook a systematic analysis on the expression and functional relevance of different mouse Slfn genes in malignant melanoma and renal cell carcinoma cells. Our studies demonstrate that several mouse Slfn genes are up-regulated in response to IFN treatment of mouse melanoma and renal cell carcinoma cells, including Slfn1, Slfn2, Slfn4, Slfn5, and Slfn8. Our data show that Slfn2 and Slfn3 play essential roles in the control of mouse malignant melanoma cell proliferation and/or anchorage-independent growth, suggesting key and non-overlapping roles for these genes in the control of malignant melanoma tumorigenesis. In renal cell carcinoma cells, in addition to Slfn2 and Slfn3, Slfn5 also exhibits important antineoplastic effects. Altogether, our findings indicate important functions for distinct mouse Slfn genes in the control of tumorigenesis and provide evidence for differential involvement of distinct members of this gene family in controlling tumorigenesis. They also raise the potential of future therapeutic approaches involving modulation of expression of members of this family of genes in malignant melanoma and renal cell carcinoma.

IL6 sensitizes prostate cancer to the antiproliferative effect of IFNα2 through IRF9

Development and progression of prostate cancer (PCa) are associated with chronic inflammation. The cytokine interleukin 6 (IL6) can influence progression, differentiation, survival, and angiogenesis of PCa. To identify novel pathways that are triggered by IL6, we performed a gene expression profiling of two PCa cell lines, LNCaP and MDA PCa 2b, treated with 5 ng/ml IL6. Interferon (IFN) regulatory factor 9 (IRF9) was identified as one of the most prevalent IL6-regulated genes in both cell lines. IRF9 is a mediator of type I IFN signaling and acts together with STAT1 and 2 to activate transcription of IFN-responsive genes. The IL6 regulation of IRF9 was confirmed at mRNA and protein levels by quantitative real-time PCR and western blot respectively in both cell lines and could be blocked by the anti-IL6 antibody Siltuximab. Three PCa cell lines, PC3, Du-145, and LNCaP-IL6+, with an autocrine IL6 loop displayed high expression of IRF9. A tissue microarray with 36 PCa tissues showed that IRF9 protein expression is moderately elevated in malignant areas and positively correlates with the tissue expression of IL6. Downregulation and overexpression of IRF9 provided evidence for an IFN-independent role of IRF9 in cellular proliferation of different PCa cell lines. Furthermore, expression of IRF9 was essential to mediate the antiproliferative effects of IFNα2. We concluded that IL6 is an inducer of IRF9 expression in PCa and a sensitizer for the antiproliferative effects of IFNα2.

Hope and fear for interferon: the receptor-centric outlook on the future of interferon therapy

After several decades of intense clinical research, the great promise of Type I interferons (IFN1) as the anticancer wonder drugs that could cure or, at the very least, curb the progression of various oncological diseases has regrettably failed to deliver. Severe side effects and low efficacy of IFN1-based pharmaceutics greatly limited use of these drugs and further reduced the enthusiasm of clinical oncologists for future optimization of IFN1-based therapeutic modalities. Incredibly, extensive clinical studies to assess the efficacy of IFN1 alone or in combination with other anticancer drugs have not been paralleled by an equal scope in defining the determinants that confer cell sensitivity or refractoriness to IFN1. Given that all effects of IFN1 on malignant and benign cells alike are mediated by its receptor, the mechanisms regulating these receptor cell surface levels should play a paramount role in shaping the magnitude and duration of IFN1-elicited effects. These mechanisms and their role in controlling IFN1 responses, as well as an ability of a growing tumor to commandeer these events, are the focus of our review. We postulate that activation of numerous signaling pathways leading to elimination of IFN1 receptor occurs in cancer cells and benign cells that contribute to tumor tissue. We further hypothesize that activation of these eliminative pathways enables the escape from IFN1-driven suppression of tumorigenesis and elicits the primary refractoriness of tumor to the pharmaceutical IFN1.

Topical chemotherapy for ocular surface squamous neoplasia

PURPOSE OF REVIEW

Ocular surface squamous neoplasia (OSSN) is an umbrella term for a spectrum of epithelial dysplasias of the cornea, conjunctiva, and limbus. Treatment for OSSN has historically been surgery, but nonsurgical interventions have been increasingly adopted. Advantages of medical treatments include the ability to treat the entire ocular surface and prevention of surgical complications.

RECENT FINDINGS

The primary medical treatments for OSSN include mitomycin C, 5-fluorouracil, and interferon α2b. Mitomycin C has been shown in studies to be highly effective but has short-term and long-term side-effects that may be intolerable. 5-Fluorouracil and interferon α2b have been found to be similar in efficacy to mitomycin, with interferon being extremely well tolerated in the majority of patients. Most recently, other chemotherapeutic agents have been tried for OSSN including antivascular endothelial growth factor agents and vitamin A. The data regarding these latter treatment strategies are still limited.

SUMMARY

An understanding of the recent literature, with respect to the efficacy, advantages, and disadvantages of the various therapies for OSSN will allow us to tailor treatment to each patient.