Immunomodulators in the treatment of cutaneous lymphoma

Antibody-Based Targeted Interventions for the Diagnosis and Treatment of Skin Cancers

BACKGROUND

Cutaneous malignancies most commonly arise from skin epidermal cells. These cancers may rapidly progress from benign to a metastatic phase. Surgical resection represents the gold standard therapeutic treatment of non-metastatic skin cancer while chemo- and/or radiotherapy are often used against metastatic tumors. However, these therapeutic treatments are limited by the development of resistance and toxic side effects, resulting from the passive accumulation of cytotoxic drugs within healthy cells.

OBJECTIVE

This review aims to elucidate how the use of monoclonal Antibodies (mAbs) targeting specific Tumor Associated Antigens (TAAs) is paving the way to improved treatment. These mAbs are used as therapeutic or diagnostic carriers that can specifically deliver cytotoxic molecules, fluorophores or radiolabels to cancer cells that overexpress specific target antigens.

RESULTS

mAbs raised against TAAs are widely in use for e.g. differential diagnosis, prognosis and therapy of skin cancers. Antibody-Drug Conjugates (ADCs) particularly show remarkable potential. The safest ADCs reported to date use non-toxic photo-activatable Photosensitizers (PSs), allowing targeted Photodynamic Therapy (PDT) resulting in targeted delivery of PS into cancer cells and selective killing after light activation without harming the normal cell population. The use of near-infrared-emitting PSs enables both diagnostic and therapeutic applications upon light activation at the specific wavelengths.

CONCLUSION

Antibody-based approaches are presenting an array of opportunities to complement and improve current methods employed for skin cancer diagnosis and treatment.

Non-surgical treatments of primary, non-melanoma eyelid malignancies: a review

The diagnosis and management of periocular cutaneous malignancies are essential components of an ophthalmologist's practice. Skin cancers comprise nearly one-third of newly diagnosed malignancies. Furthermore, the incidence of skin cancer appears to be increasing. Multiple treatment modalities exist for periocular cutaneous malignancy. Surgical extirpation, often with the combined expertise of a Mohs micrographic surgeon, is typically the first line therapy and is often curative in the periocular region, depending on a variety of factors, including tumour histology, specific location, depth of invasion and surgical technique. However, there are instances where a less invasive, non-surgical treatment option is warranted, including patients who are poor surgical risks or those with diffuse disease. The purpose of this article is to review the literature and describe the non-surgical treatment options, indications and efficacies for non-melanoma primary eyelid malignancies.

Role of imiquimod in skin cancer treatment

Cancer of the skin is by far the most common form of all cancers. Given the increasing incidence of skin cancer worldwide, it seems feasible to reconsider the treatment options available for dealing with this growing problem. Despite the lower costs associated with classical methods such as surgery and radiotherapy, immune response modifiers such as imiquimod appear to be good candidates for the future given their good cosmetic effects, the possibility of treating large areas, and the simpleness of patient-applied treatment with a cream formulation. This article reviews current literature on the use of imiquimod in the treatment of nonmelanoma and melanoma skin cancer.

Immunomodulators in the treatment of cutaneous lymphomas

Cutaneous lymphomas (CLs) are a heterogeneous group of lymphoproliferative cutaneous neoplasms that in many cases cannot be cured by standard radio- and chemotherapy. Immunotherapy holds promise for a well-tolerated treatment approach that allows long-time disease control. Unspecific immunotherapy such as IFNs is successfully used in cutaneous T-cell lymphomas (CTCLs). Antibiotic treatment is often effective in cutaneous B-cell lymphomas (CBCLs). New treatment approaches include fusion toxins and chimeric monoclonal antibodies (mAbs) such as rituximab for CBCLs. The identification of tumour antigens in CTCLs renders these diseases susceptible for vaccination approaches.

Immunotherapy for nonmelanoma skin cancer: does it have a future?

BACKGROUND

Basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) of the skin are the most common malignancies in the white human population, accounting for greater than 95% of nonmelanoma skin cancers (NMSCs). Current data show an increasing incidence of NMSC in recent decades. Although the mortality is low, this cancer group is associated with substantial morbidity. Multiple treatment modalities are available for NMSC, with surgery being a "cornerstone" of current therapy approaches. However, in patients with multiple lesions or in cases of tumors on critical locations, disfigurement and the disease recurrence may represent a serious problem associated with the surgical treatment. The purpose of this study was to review and analyze whether NMSC could represent a target for immune therapy, evaluating the aspects of the availability of tumor antigens and the existence of tumor specific immune response, including a summary of the major clinical studies dealing with immunotherapy for NMSC.

METHODS

The authors have reviewed the available medical literature on NMSC, with a focus on tumor immunology and associated abnormalities, as well as immunotherapy-based treatment trials.

RESULTS

The major advantage of NMSCs is that they arise from the skin, which makes them easily detectable and treatable. Furthermore, these tumors posses all the prerequisites, i.e., the presence of tumor-associated antigens as well as the tumor specific immune response, needed for immune intervention. This also was confirmed in various studies demonstrating clinical efficacy of cytokines and other immune response modifiers.

CONCLUSIONS

In addition to clinical cure, by activating and stimulating patient's immune resources this therapeutic option may be a "silver bullet," providing a long-term protective immunity against initial tumor.

Serological detection of cutaneous T-cell lymphoma-associated antigens

Cutaneous T-cell lymphomas (CTCL) are a group of skin neoplasms that originate from T lymphocytes and are difficult to treat in advanced stages. The present study is aimed at the identification of tumor-specific antigens from a human testis cDNA library using human sera known as the SEREX (serological identification of recombinantly expressed genes) approach. A cDNA library from normal testicle tissue was prepared and approximately 2 million recombinants were screened with sera from Sézary Syndrome and Mycosis fungoides patients. A total of 28 positive clones belonging to 15 different genes/ORFs were identified, including five hitherto unknown sequences. Whereas control sera did not react with most clones, 11-71% sera from CTCL patients were reactive against the identified clones. Expression analysis on 28 normal control and 17 CTCL tissues by reverse transcription-PCR (RT-PCR) and Northern blotting revealed seven ubiquitously distributed antigens, six differentially expressed antigens (several normal tissues were positive), and two tumor-specific antigens that were expressed only in testis and tumor tissues: (i) A SCP-1-like sequence, which has already been detected in various tumors, has been found in one CTCL tumor and four sera of CTCL patients reacted with various SCP-1-like clones and (ii) a new sequence named cTAGE-1 (CTCL-associated antigen 1) was detected in 35% of CTCL tumor tissues and sera of 6/18 patients reacted with this clone. The present study unravels CTCL-associated antigens independent of the T-cell receptor. The SCP-1-like gene and cTAGE-1 were shown to be immunogenic and immunologically tumor-specific and may therefore be candidates for immunotherapy targeting CTCL.

Primary cutaneous lymphomas

Primary cutaneous lymphomas have a distinct clinical behavior and prognosis, and therefore require a different therapeutic approach, as compared with their primary nodal equivalents. The European Organization for Research and Treatment of Cancer (EORTC) classification for primary cutaneous lymphomas recognizes a limited number of cutaneous T-cell lymphomas and cutaneous B-cell lymphomas and is at present the best guide to optimal management and treatment of these conditions. Herein, the relationship between the EORTC classification and the recently published World Health Organization classification is discussed, and recent developments regarding the main types of cutaneous T-cell lymphomas and cutaneous B-cell lymphomas recognized in the EORTC classification are presented.