Presence of the human leukocyte antigen class II gene DRB1*1101 predicts interferon gamma levels and disease recurrence in melanoma patients

Development of preclinical and clinical models for immune-related adverse events following checkpoint immunotherapy: a perspective from SITC and AACR

Recent advances in cancer immunotherapy have completely revolutionized cancer treatment strategies. Nonetheless, the increasing incidence of immune-related adverse events (irAEs) is now limiting the overall benefits of these treatments. irAEs are well-recognized side effects of some of the most effective cancer immunotherapy agents, including antibody blockade of the cytotoxic T-lymphocyte-associated protein 4 and programmed death protein 1/programmed-death ligand 1 pathways. To develop an action plan on the key elements needed to unravel and understand the key mechanisms driving irAEs, the Society for Immunotherapy for Cancer and the American Association for Cancer Research partnered to bring together research and clinical experts in cancer immunotherapy, autoimmunity, immune regulation, genetics and informatics who are investigating irAEs using animal models, clinical data and patient specimens to discuss current strategies and identify the critical next steps needed to create breakthroughs in our understanding of these toxicities. The genetic and environmental risk factors, immune cell subsets and other key immunological mediators and the unique clinical presentations of irAEs across the different organ systems were the foundation for identifying key opportunities and future directions described in this report. These include the pressing need for significantly improved preclinical model systems, broader collection of biospecimens with standardized collection and clinical annotation made available for research and integration of electronic health record and multiomic data with harmonized and standardized methods, definitions and terminologies to further our understanding of irAE pathogenesis. Based on these needs, this report makes a set of recommendations to advance our understanding of irAE mechanisms, which will be crucial to prevent their occurrence and improve their treatment.

Mobile phone specific electromagnetic fields induce transient DNA damage and nucleotide excision repair in serum-deprived human glioblastoma cells

Some epidemiological studies indicate that the use of mobile phones causes cancer in humans (in particular glioblastomas). It is known that DNA damage plays a key role in malignant transformation; therefore, we investigated the impact of the UMTS signal which is widely used in mobile telecommunications, on DNA stability in ten different human cell lines (six brain derived cell lines, lymphocytes, fibroblasts, liver and buccal tissue derived cells) under conditions relevant for users (SAR 0.25 to 1.00 W/kg). We found no evidence for induction of damage in single cell gel electrophoresis assays when the cells were cultivated with serum. However, clear positive effects were seen in a p53 proficient glioblastoma line (U87) when the cells were grown under serum free conditions, while no effects were found in p53 deficient glioblastoma cells (U251). Further experiments showed that the damage disappears rapidly in U87 and that exposure induced nucleotide excision repair (NER) and does not cause double strand breaks (DSBs). The observation of NER induction is supported by results of a proteome analysis indicating that several proteins involved in NER are up-regulated after exposure to UMTS; additionally, we found limited evidence for the activation of the γ-interferon pathway. The present findings show that the signal causes transient genetic instability in glioma derived cells and activates cellular defense systems.

Long-term outcomes of helper peptide vaccination for metastatic melanoma

OBJECTIVE

The objective of this study was to compare the long-term outcome of patients with metastatic melanoma vaccinated with 6MHP to that of a group of unvaccinated historical controls.

BACKGROUND

A multipeptide vaccine (6MHP), designed to induce helper T cells against melanocytic and cancer-testis antigens, has been shown to induce specific Th1-dominant CD4+ T cell responses.

METHODS

The 6MHP vaccine was administered to patients with metastatic melanoma. Circulating CD4+ T cell responses were measured by proliferation or direct IFN-gamma ELIspot assay. Overall survival of vaccinated patients was compared to a group of clinically comparable historical controls using multivariable Cox regression analysis and Kaplan-Meier survival analysis, taking into account age, metastatic site, and resection status.

RESULTS

Across 40 vaccinated patients and 87 controls, resection status (HR 0.54, P = 0.004) and vaccination (HR 0.24, P < 0.001) were associated with improved overall survival. Forty pairs of vaccinated patients and controls were matched by metastatic site, resection status, and age within 10 years. Median survival was significantly longer for vaccinated patients (5.4 vs 1.3 years, P < 0.001). Among the vaccinated patients, the development of a specific immune response after vaccination was associated with improved survival (HR 0.35, P = 0.040).

CONCLUSIONS

Helper peptide vaccination is associated with improved overall survival among patients with metastatic melanoma. These data support a randomized prospective trial of the 6MHP vaccine.

Immunologic functions as prognostic indicators in melanoma

Outcome in melanoma patients with advanced disease is poor and systemic treatment seems to benefit only a subset of patients. Predictive markers identifying these patients are currently not available. Early studies showed an association of immune-related side effects such as vitiligo and autoimmune thyroiditis with response to IL-2 or IFNα treatment. However, conflicting data have been reported as well, mentioning the effect of a higher rate of immune-related toxicities during prolonged administration of the drug in responders. The review discusses the prognostic significance of autoimmunity during various forms of immunotherapy and stresses the importance of correcting for guarantee-time bias. In addition, other immune-related factors which have been associated with melanoma prognosis such as, CRP, white blood cell count, absolute lymphocyte count and human leukocyte antigen will be reviewed as well. A better understanding of the immune system and the host-tumor interactions should ultimately lead to more effective treatment. A major challenge expected to be addressed in future is proving ways to uncouple tumor immunity from autoimmunity.

Correlation of molecular human leukocyte antigen typing and outcome in high-risk melanoma patients receiving adjuvant interferon

BACKGROUND:

Interferon is approved for adjuvant treatment of patients with stage IIB/III melanoma. The identification of predictive markers that would permit selection of patients would be beneficial. Specific human leukocyte antigen (HLA) class I and II antigens have previously shown an association with response to therapy or overall survival of patients with metastatic melanoma.

METHODS:

A total of 284 high-risk melanoma patients participating in a randomized trial and 246 healthy controls were molecularly typed for HLA class I and II. Specific allele frequencies were compared between the healthy and patient populations, as well as presence or absence of these in relation to recurrence. Alleles related to autoimmune disease were also investigated.

RESULTS:

No significant differences were found between the distribution of HLA genotype in the melanoma population compared with healthy controls. Correlations between nonrecurrence and the presence of HLA-Cw*06 allele were noted present in 19.3% of melanoma patients. The median relapse-free survival of the Cw*06-positive cohort was 100.2 months versus 37.3 months in the Cw*06-negative cohort (P = .013). The median overall survival for the Cw*06-positive cohort has not yet been reached, versus 78.9 months in the Cw*06-negative cohort (P = .025). HLA-Cw*06 was present in 29.79% of patients in the autoimmunity group and 15.38% of patients in the nonautoimmunity group (P = .049).

CONCLUSIONS:

No allele was associated with absence of recurrence in patients receiving adjuvant interferon with the exception of HLA-Cw*06, an allele correlated with psoriasis. HLA-Cw*06-positive patients have better relapse-free and overall survival. Cancer 2010. © 2010 American Cancer Society.

Loss of expression of antigen-presenting molecules in human pancreatic cancer and pancreatic cancer cell lines

Tumours evade immune recognition and destruction through loss or down-regulation of expression of antigen processing and antigen-presenting molecules such as the human leucocyte antigen (HLA class I) and transporter for antigen presentation (TAP). This study examined the expression of HLA class I, class II and TAP in human pancreatic carcinoma tissue and 19 immortalized pancreatic cancer lines using a panel of antibodies directed against allele-specific as well as monomorphic determinants of these molecules. In tissue samples, reduction or loss of HLA class I and TAP was observed in 76% of cases, loss or down-regulation of TAP expression in 53%. In pancreatic cell lines down-regulation or loss of class I and TAP expression was also observed frequently. However, reductions in class I and TAP expression were reversible upon exposure to interferon-gamma in vitro, suggesting a regulatory rather than structural defect in these genes. De novo class II expression was observed in 26% of tumours and 42% of cell lines and may reflect the differentiation status of the cells. The high rate of class I and TAP loss has implications for immunotherapy strategies for pancreatic cancer, as such changes could facilitate a selective growth advantage for malignant cells. However, the reinduction of expression of these molecules with cytokines such as interferon-gamma may ultimately allow their cytotoxic T cell-mediated destruction.

HLA class II profile and distribution of HLA-DRB1 and HLA-DQB1 alleles and haplotypes among Lebanese and Bahraini Arabs

The gene frequencies of HLA class II alleles were studied in 95 healthy Lebanese Arab and 72 healthy Bahraini Arab subjects. Our aim was to establish the genetic relationship between Bahraini and Lebanese Arabs in terms of HLA class II gene and haplotype frequencies and to compare these results with frequencies for other countries with populations of Caucasian and non-Caucasian descent. Subjects were unrelated and of both sexes, and HLA-DRB1 and -DQB1 genotyping was done by the PCR sequence-specific primer technique. Comparative analysis of the HLA-DR and -DQ alleles revealed differences in the allelic distribution among Bahraini and Lebanese subjects. Analysis of the 25 HLA-DRB1 alleles that have been investigated showed that the DRB1*040101 and DRB1*110101 alleles were more frequent among Lebanese, whereas DRB1*030101 and DRB1*160101 alleles were more frequent among Bahrainis. Similarly, of the seven HLA-DQB1 alleles analyzed, the presence of DQB1*0201 was more frequent among Bahrainis, whereas DQB1*030101 was more frequent among Lebanese. The DRB1*160101-DQB1*050101 (0.1318 versus 0.0379%) and DRB1*030101-DQB1*0201 (0.1202 versus 0.0321%) haplotypes were more frequent among Bahrainis, while the DRB1*110101-DQB1*030101 (0.3142 versus 0.1198%) and DRB1*040101-DQB1*0302 (0.1416 versus 0.0278%) haplotypes were more frequent in Lebanese subjects. Furthermore, a high prevalence of the DRB1*040101-DRB1*110101-DQB1*0302-DQB1*030101 (12.63 versus 1.35%, P = 0.015) and the homozygous DRB1*110101-DRB1*110101-DQB1*030101-DQB1*030101 (7.37 versus 0.00%, P = 0.046) genotypes was seen among Lebanese, and DRB1*070101-DRB1*160101-DQB1*0201-DQB1*050101 (6.76 versus 0.00%, P = 0.034) was seen more frequently among Bahraini subjects. Our results underline significant differences between these two populations in HLA class II distribution, provide basic information for further studies of major histocompatibility complex heterogeneity among Arabic-speaking countries, and serve as a reference for further anthropological studies.