An update on pegylated IFN-α2b for the adjuvant treatment of melanoma

Magnetic Relaxation Switching Assay Using IFNα-2b-Conjugated Superparamagnetic Nanoparticles for Anti-Interferon Antibody Detection

Type I interferons, particularly IFNα-2b, play essential roles in eliciting adaptive and innate immune responses, being implicated in the pathogenesis of various diseases, including cancer, and autoimmune and infectious diseases. Therefore, the development of a highly sensitive platform for analysis of either IFNα-2b or anti-IFNα-2b antibodies is of high importance to improve the diagnosis of various pathologies associated with the IFNα-2b disbalance. For evaluation of the anti-IFNα-2b antibody level, we have synthesized superparamagnetic iron oxide nanoparticles (SPIONs) coupled with the recombinant human IFNα-2b protein (SPIONs@IFNα-2b). Employing a magnetic relaxation switching assay (MRSw)-based nanosensor, we detected picomolar concentrations (0.36 pg/mL) of anti-INFα-2b antibodies. The high sensitivity of the real-time antibodies' detection was ensured by the specificity of immune responses and the maintenance of resonance conditions for water spins by choosing a high-frequency filling of short radio-frequency pulses of the generator. The formation of a complex of the SPIONs@IFNα-2b nanoparticles with the anti-INFα-2b antibodies led to a cascade process of the formation of nanoparticle clusters, which was further enhanced by exposure to a strong (7.1 T) homogenous magnetic field. Obtained magnetic conjugates exhibited high negative MR contrast-enhancing properties (as shown by NMR studies) that were also preserved when particles were administered in vivo. Thus, we observed a 1.2-fold decrease of the T2 relaxation time in the liver following administration of magnetic conjugates as compared to the control. In conclusion, the developed MRSw assay based on SPIONs@IFNα-2b nanoparticles represents an alternative immunological probe for the estimation of anti-IFNα-2b antibodies that could be further employed in clinical studies.

Direct and indirect effects of IFN-α2b in malignancy treatment: not only an archer but also an arrow

Interferon-α2b (IFN-α2b) is a highly active cytokine that belongs to the interferon-α (IFN-α) family. IFN-α2b has beneficial antiviral, antitumour, antiparasitic and immunomodulatory activities. Direct and indirect antiproliferative effects of IFN-α2b have been found to occur via multiple pathways, mainly the JAK-STAT pathway, in certain cancers. This article reviews mechanistic studies and clinical trials on IFN-α2b. Potential regulators of the function of IFN-α2b were also reviewed, which could be utilized to relieve the poor response to IFN-α2b. IFN-α2b can function not only by enhancing the systematic immune response but also by directly killing tumour cells. Different parts of JAK-STAT pathway activated by IFN-α2b, such as interferon alpha and beta receptors (IFNARs), Janus kinases (JAKs) and IFN‐stimulated gene factor 3 (ISGF3), might serve as potential target for enhancing the pharmacological action of IFN-α2b. Despite some issues that remain to be solved, based on current evidence, IFN-α2b can inhibit disease progression and improve the survival of patients with certain types of malignant tumours. More efforts should be made to address potential adverse effects and complications.

Cancer immunotherapy: are we there yet?

The immune system is the built-in host defense mechanism against infectious agents as well as cancer. Protective immunity against cancer was convincingly demonstrated in the 1940s with syngeneic animal models (JNCI 18:769-778, 1976; Cancer Immun 1:6, 2001). Since then, the last century’s dream has been to effectively prevent and cure cancers by immunological means. This dream has slowly but surely become a reality (Nature 480:480-489, 2011). The successful examples of immunoprophylaxis and therapy against cancers include: (i) targeted therapy using monoclonal antibodies (Nat Rev Cancer 12:278-287, 2012); (ii) allogeneic hematopoietic stem cell transplantion to elicit graft-versus-cancer effect against a variety of hematopoietic malignancies (Blood 112:4371-4383, 2008); (iii) vaccination for preventing cancers with clear viral etiology such as hepatocellular carcinoma and cervical cancer (Cancer J Clin 57:7-28, 2007; NEJM 336:1855-1859, 1997); (iv) T cell checkpoint blockade against inhibitory pathways including targeting CTLA-4 and PD-1 inhibitory molecules for the treatment of melanoma and other solid tumors (NEJM 363:711-723, 2010; NEJM 366:2443-2454, 2012; NEJM 369:122-133, 2013; NEJM 366:2455-2465, 2012); (v) antigen-pulsed autologous dendritic cell vaccination against prostate cancer (NEJM 363:411-422, 2010); and (vi) the transfer of T cells including those genetically engineered with chimeric antigen receptors allowing targeting of B cell neoplasms (NEJM 365:725-733, 2011; NEJM 368:1509-1518, 2013; Blood 118:4817-4828, 2013; Sci Transl Med 5:177ra138, 2013).

This article provides an overview on the exciting and expanding immunological arsenals against cancer, and discusses critical remaining unanswered questions of cancer immunology. The inherent specificity and memory of the adaptive immune response towards cancer will undoubtedly propel cancer immunotherapy to the forefront of cancer treatment in the immediate near future. Study of the fundamental mechanisms of the immune evasion of cancer shall also advance the field of immunology towards the development of effective immunotherapeutics against a wide spectrum of human diseases.