HLA-C

Gene Summary

Gene:HLA-C; major histocompatibility complex, class I, C
Aliases: MHC, HLAC, HLC-C, D6S204, PSORS1, HLA-JY3
Location:6p21.33
Summary:HLA-C belongs to the HLA class I heavy chain paralogues. This class I molecule is a heterodimer consisting of a heavy chain and a light chain (beta-2 microglobulin). The heavy chain is anchored in the membrane. Class I molecules play a central role in the immune system by presenting peptides derived from endoplasmic reticulum lumen. They are expressed in nearly all cells. The heavy chain is approximately 45 kDa and its gene contains 8 exons. Exon one encodes the leader peptide, exons 2 and 3 encode the alpha1 and alpha2 domain, which both bind the peptide, exon 4 encodes the alpha3 domain, exon 5 encodes the transmembrane region, and exons 6 and 7 encode the cytoplasmic tail. Polymorphisms within exon 2 and exon 3 are responsible for the peptide binding specificity of each class one molecule. Typing for these polymorphisms is routinely done for bone marrow and kidney transplantation. Over one hundred HLA-C alleles have been described [provided by RefSeq, Jul 2008]
Databases:OMIM, HGNC, Ensembl, GeneCard, Gene
Protein:HLA class I histocompatibility antigen, Cw-1 alpha chain
Source:NCBIAccessed: 31 August, 2019

Ontology:

What does this gene/protein do?
Show (22)
Pathways:What pathways are this gene/protein implicaed in?
Show (4)

Cancer Overview

Research Indicators

Publications Per Year (1994-2019)
Graph generated 01 September 2019 using data from PubMed using criteria.

Literature Analysis

Mouse over the terms for more detail; many indicate links which you can click for dedicated pages about the topic.

  • Pedigree
  • Uterine Cancer
  • Retinoblastoma
  • Chromosome 6
  • Genetic Recombination
  • Cervical Cancer
  • Adolescents
  • Single Nucleotide Polymorphism
  • Unrelated Donors
  • T-Lymphocytes
  • Genotype
  • Spain
  • Mexico
  • Genetic Predisposition
  • Hematopoietic Stem Cell Transplantation
  • Sequence Homology, Nucleic Acid
  • Natural Killer Cells
  • Haplotypes
  • Vaccination
  • Histocompatibility Testing
  • Homologous Transplantat
  • Alleles
  • Republic of Korea
  • Phenotype
  • HLA Antigens
  • Transplantation
  • Testicular Cancer
  • Receptors, KIR
  • HLA-A
  • HLA-B
  • DNA Sequence Analysis
  • HLA-DR Antigens
  • Melanoma
  • Pancreatic Cancer
  • Polymerase Chain Reaction
  • Childhood Cancer
  • Base Sequence
  • Urinary Bladder
  • Case-Control Studies
  • Receptors, KIR2DL2
  • Virus Integration
  • HLA-C Antigens
  • Young Adult
  • T-Lymphocytes, Cytotoxic
  • Transplant Recipients
Tag cloud generated 31 August, 2019 using data from PubMed, MeSH and CancerIndex

Specific Cancers (6)

Data table showing topics related to specific cancers and associated disorders. Scope includes mutations and abnormal protein expression.

Note: list is not exhaustive. Number of papers are based on searches of PubMed (click on topic title for arbitrary criteria used).

Latest Publications: HLA-C (cancer-related)

Garrido F
HLA Class-I Expression and Cancer Immunotherapy.
Adv Exp Med Biol. 2019; 1151:79-90 [PubMed] Related Publications
The impact of HLA class I loss in cancer immunotherapy is carefully analyzed. Why some metastatic lesions regress and other progress after immunotherapy? Are T lymphocytes responsible for tumour rejection and how these responses can be boosted? These questions are discussed in the context of the molecular mechanisms responsible for MHC/HLA class I alterations. If the metastatic tumour cells harbor "irreversible/hard" HLA lesions, they will escape and kill the host. In contrast, if the molecular lesion is "reversible/soft", tumor cells can potentially recover HLA-class I expression and can finally be destroyed. These important new concepts are integrated together and gain a great importance in the new era of "immune checkpoint antibodies". Finally, the ability to recover HLA-I expression in tumours harboring "structural-irreversible-hard" genetic lesions is seen as a challenge for the future investigation.

Ugurel S, Spassova I, Wohlfarth J, et al.
MHC class-I downregulation in PD-1/PD-L1 inhibitor refractory Merkel cell carcinoma and its potential reversal by histone deacetylase inhibition: a case series.
Cancer Immunol Immunother. 2019; 68(6):983-990 [PubMed] Related Publications
BACKGROUND: Merkel cell carcinoma (MCC) is an aggressive skin cancer in which PD-1/PD-L1 blockade has shown remarkable response rates. However, a significant proportion of patients shows primary or secondary resistance against PD-1/PD-L1 inhibition, with HLA class-I downregulation and insufficient influx of CD8
CASE PRESENTATIONS: We report four cases of patients with metastatic MCC who did not respond to immunotherapy by PD-1/PD-L1 blockade. Two of the patients received, subsequently, the HDACi panobinostat in combination with PD-1/PD-L1 blockade. Tumor biopsies of the patients were analyzed for cellular and molecular markers of antigen processing and presentation as well as the degree of T-cell infiltration.
RESULTS AND CONCLUSION: Low expression of APM-related genes associated with low HLA class-I surface expression was observed in all MCC patients, progressing on PD-1/PD-L1 blockade. In one evaluable patient, of the two treated with the combination therapy of the HDACi, panobinostat and PD-1/PD-L1 blockade, reintroduction of HLA class-I-related genes, enhanced HLA class-I surface expression, and elevated CD8

Yu Y, Blokhuis BR, Garssen J, Redegeld FA
A Transcriptomic Insight into the Impact of Colon Cancer Cells on Mast Cells.
Int J Mol Sci. 2019; 20(7) [PubMed] Free Access to Full Article Related Publications
Mast cells (MCs) are one of the first immune cells recruited to a tumor. It is well recognized that MCs accumulate in colon cancer lesion and their density is associated with the clinical outcomes. However, the molecular mechanism of how colon cancer cells may modify MC function is still unclear. In this study, primary human MCs were generated from CD34⁺ progenitor cells and a 3D coculture model was developed to study the interplay between colon cancer cells and MCs. By comparing the transcriptomic profile of colon cancer-cocultured MCs versus control MCs, we identified a number of deregulated genes, such as MMP-2, VEGF-A, PDGF-A, COX2, NOTCH1 and ISG15, which contribute to the enrichment of cancer-related pathways. Intriguingly, pre-stimulation with a TLR2 agonist prior to colon cancer coculture induced upregulation of multiple interferon-inducible genes as well as MHC molecules in MCs. Our study provides an alternative approach to study the influence of colon cancer on MCs. The transcriptome signature of colon cancer-cocultured MCs may potentially reflect the mechanism of how colon cancer cells educate MCs to become pro-tumorigenic in the initial phase and how a subsequent inflammatory signal-e.g., TLR2 ligands-may modify their responses in the cancer milieu.

Liu S, Han Z, Trivett AL, et al.
Cryptotanshinone has curative dual anti-proliferative and immunotherapeutic effects on mouse Lewis lung carcinoma.
Cancer Immunol Immunother. 2019; 68(7):1059-1071 [PubMed] Free Access to Full Article Related Publications
Lung cancer is currently the leading cause of cancer-related mortality with very limited effective therapy. Screening of a variety of traditional Chinese medicines (TCMs) for their capacity to inhibit the proliferation of human lung cancer A549 cells and to induce the in vitro maturation of human DCs led to the identification of cryptotanshinone (CT), a compound purified from the TCM Salvia miltiorrhiza Bunge. Here, CT was shown to inhibit the proliferation of mouse Lewis lung carcinoma (LLC) cells by upregulating p53, downregulating cyclin B1 and Cdc2, and, consequently, inducing G2/M cell-cycle arrest of LLC cells. In addition, CT promoted maturation of mouse and human DCs with upregulation of costimulatory and MHC molecules and stimulated DCs to produce TNFα, IL-1β, and IL-12p70, but not IL-10 in vitro. CT-induced maturation of DCs depended on MyD88 and also involved the activation of NF-κB, p38, and JNK. CT was effective in the treatment of LLC tumors and, when used in combination with low doses of anti-PD-L1, cured LLC-bearing mice with the induction of subsequent anti-LLC long-term specific immunity. CT treatment promoted T-cell infiltration and elevated the expression of genes typical of Th1 polarization in LLC tumor tissue. The therapeutic effect of CT and low doses of anti-PD-L1 was reduced by depletion of CD4 and CD8 T cells. This paper provides the first report that CT induces immunological antitumor activities and may provide a new promising antitumor immunotherapeutic.

Klein S, Mauch C, Wagener-Ryczek S, et al.
Immune-phenotyping of pleomorphic dermal sarcomas suggests this entity as a potential candidate for immunotherapy.
Cancer Immunol Immunother. 2019; 68(6):973-982 [PubMed] Related Publications
BACKGROUND: Pleomorphic dermal sarcomas (PDS) are sarcomas of the skin with local recurrences in up to 28% of cases, and distant metastases in up to 20%. Although recent evidence provides a strong rational to explore immunotherapeutics in solid tumors, nothing is known about the immune environment of PDS.
METHODS: In the current study, a comprehensive immune-phenotyping of 14 PDS using RNA and protein expression analyses, as well as quantitative assessment of immune cells using an image-analysis tool was performed.
RESULTS: Three out of 14 PDS revealed high levels of CD8-positive tumor-infiltrating T-lymphocytes (TILs), also showing elevated levels of immune-related cytokines such as IL1A, IL2, as well as markers that were very recently linked to enhanced response of immunotherapy in malignant melanoma, including CD27, and CD40L. Using a multivariate analysis, we found a number of differentially expressed genes in the CD8-high group including: CD74, LYZ and HLA-B, while the remaining cases revealed enhanced levels of immune-suppressive cytokines including CXCL14. The "CD8-high" PDS showed strong MHC-I expression and revealed infiltration by PD-L1-, PD-1- and LAG-3-expressing immune cells. Tumor-associated macrophages (TAMs) predominantly consisted of CD68 + , CD163 + , and CD204 + M2 macrophages showing an accentuation at the tumor invasion front.
CONCLUSIONS: Together, we provide first explorative evidence about the immune-environment of PDS tumors that may guide future decisions whether individuals presenting with advanced PDS could qualify for immunotherapeutic options.

Lu M, Peng L, Ming X, et al.
Enhanced wound healing promotion by immune response-free monkey autologous iPSCs and exosomes vs. their allogeneic counterparts.
EBioMedicine. 2019; 42:443-457 [PubMed] Free Access to Full Article Related Publications
BACKGROUND: Comparing non-inbred autologous and allogeneic induced pluripotent stem cells (iPSCs) and their secreted subcellular products among non-human primates is critical for choosing optimal iPSC products for human clinical trials.
METHODS: iPSCs were induced from skin fibroblastic cells of adult male rhesus macaques belonging to four unrelated consanguineous families. Teratoma generativity, host immune response, and skin wound healing promotion were evaluated subsequently.
FINDINGS: All autologous, but no allogeneic, iPSCs formed teratomas, whereas all allogeneic, but no autologous, iPSCs caused lymphocyte infiltration. Macrophages were not detectable in any wound. iPSCs expressed significantly more MAMU A and E of the major histocompatibility complex (MHC) class I but not more other MHC genetic alleles than parental fibroblastic cells. All topically disseminated autologous and allogeneic iPSCs, and their exosomes accelerated skin wound healing, as demonstrated by wound closure, epithelial coverage, collagen deposition, and angiogenesis. Allogeneic iPSCs and their exosomes were less effective and viable than their autologous counterparts. Some iPSCs differentiated into new endothelial cells and all iPSCs lost their pluripotency in 14 days. Exosomes increased cell viability of injured epidermal, endothelial, and fibroblastic cells in vitro. Although exosomes contained some mRNAs of pluripotent factors, they did not impart pluripotency to host cells.
INTERPRETATION: Although all of the autologous and allogeneic iPSCs and exosomes accelerated wound healing, allogeneic iPSC exosomes were the preferred choice for "off-the shelf" iPSC products, owing to their mass-production, with no concern of teratoma formation. FUND: National Natural Science Foundation of China and National Key R&D Program of China.

Mochizuki K, Kawana S, Yamada S, et al.
Various checkpoint molecules, and tumor-infiltrating lymphocytes in common pediatric solid tumors: Possibilities for novel immunotherapy.
Pediatr Hematol Oncol. 2019; 36(1):17-27 [PubMed] Related Publications
Long-term survival rates for pediatric patients with cancer have significantly improved, but novel approaches are desired for those with refractory/relapsed solid tumors. Recently, programed cell death-1/programed cell death-ligand-1 blockade has emerged as an effective option for many intractable cancers. However, not all patients show objective response to such therapy. On the other hand, several other checkpoint pathways, including Herpes virus entry mediator (HVEM)/B- and T-lymphocyte attenuator (BTLA), galectin-9 (GAL9)/T-cell immunoglobulin and mucin domain-3 (TIM3), and major histocompatibility complex class II (MHC-II)/lymphocyte activation gene-3 (LAG3), also regulate immune responses in the tumor microenvironment and may be alternative targets for novel immune therapies. In this study, we examined 65 common pediatric solid tumors and characterized the expression of Herpes virus entry mediator, GAL9, and MHC-II on tumor cells and their corresponding receptors B- and T-lymphocyte attenuator, TIM3, and LAG3, respectively, on tumor-infiltrating lymphocytes (TILs) with immunohistochemistry. Whereas the expression of GAL9 and MHC-II was limited, 73% of rhabdomyosarcomas and 100% of osteosarcomas expressed moderate to high levels of Herpes virus entry mediator on the tumor. TILs were detected in all tumor samples except one osteosarcoma. Interestingly, 45% of rhabdomyosarcomas, and 45% of osteosarcomas expressed moderate to high levels of both Herpes virus entry mediator on the tumor cells and B- and T-lymphocyte attenuator on the TILs. Results showed that a subset of pediatric solid tumors expressed tumor-associated checkpoint molecules, and TILs expressed corresponding receptors for these checkpoint molecules. Thus, immunogenic environments may be created, and checkpoint blockade may induce favorable immune responses.

Shen FF, Pan Y, Li JZ, et al.
High expression of HLA-DQA1 predicts poor outcome in patients with esophageal squamous cell carcinoma in Northern China.
Medicine (Baltimore). 2019; 98(8):e14454 [PubMed] Free Access to Full Article Related Publications
BACKGROUND: Our previous studies demonstrate that the major histocompatibility complex (MHC) is associated with the progression of esophageal squamous cell carcinoma (ESCC). HLA-DQA1, which belongs to the MHC Class II family, may be a potential biomarker in ESCC progression. However, the association between HLA-DQA1 and ESCC in high-incidence area of northern China has not been well characterized. The purpose of this study is to investigate the relationship of HLA-DQA1 expression with the progression and prognosis of ESCC.
METHODS: We analyzed the expression profiles of HLA-DQA1 in esophageal cancer (EC) samples in the TCGA database and validated HLA-DQA1 expression by immunohistochemistry, western blotting, and quantitative reverse-transcription polymerase chain reaction in matched EC and normal tissues, respectively. The correlation between HLA-DQA1 expression and clinicopathologic characteristics of ESCC was further analyzed.
RESULT: Immunohistochemical analysis indicated that the expression level of HLA-DQA1 in ESCC tissues was significantly higher than the matched normal tissues (P < .001). HLA-DQA1 mRNA and protein expression were significantly higher in ESCC tissues compared to the matched normal tissues. Patients with family history negative or with tumor sizes >4 cm were associated with higher HLA-DQA1 expression levels. A prognostic significance of HLA-DQA1 was also found by the Log-rank method, in which high expression of HLA-DQA1 was correlated with a shorter overall survival time. The receiver operating characteristic (ROC) curve analysis yielded the area under the ROC curve value of 0.693. Univariate and multivariate analyses also suggest that high expression of HLA-DQA1 is a potential indicator for poor prognosis of ESCC.
CONCLUSIONS: Our results demonstrate that HLA-DQA1 plays an important role in ESCC progression and may be a biomarker for ESCC diagnosis and prognosis, as well as a potential target for the treatment of patients with ESCC.

Ott M, Avendaño-Guzmán E, Ullrich E, et al.
Laquinimod, a prototypic quinoline-3-carboxamide and aryl hydrocarbon receptor agonist, utilizes a CD155-mediated natural killer/dendritic cell interaction to suppress CNS autoimmunity.
J Neuroinflammation. 2019; 16(1):49 [PubMed] Free Access to Full Article Related Publications
BACKGROUND: Quinoline-3-carboxamides, such as laquinimod, ameliorate CNS autoimmunity in patients and reduce tumor cell metastasis experimentally. Previous studies have focused on the immunomodulatory effect of laquinimod on myeloid cells. The data contained herein suggest that quinoline-3-carboxamides improve the immunomodulatory and anti-tumor effects of NK cells by upregulating the adhesion molecule DNAX accessory molecule-1 (DNAM-1).
METHODS: We explored how NK cell activation by laquinimod inhibits CNS autoimmunity in experimental autoimmune encephalomyelitis (EAE), the most utilized model of MS, and improves immunosurveillance of experimental lung melanoma metastasis. Functional manipulations included in vivo NK and DC depletion experiments and in vitro assays of NK cell function. Clinical, histological, and flow cytometric read-outs were assessed.
RESULTS: We demonstrate that laquinimod activates natural killer (NK) cells via the aryl hydrocarbon receptor and increases their DNAM-1 cell surface expression. This activation improves the cytotoxicity of NK cells against B16F10 melanoma cells and augments their immunoregulatory functions in EAE by interacting with CD155
CONCLUSIONS: This study clarifies how DNAM-1 modifies the bidirectional crosstalk of NK cells with CD155

Suzuki R, Matsuda M, Shimoike T, et al.
Activation of protein kinase R by hepatitis C virus RNA-dependent RNA polymerase.
Virology. 2019; 529:226-233 [PubMed] Related Publications
Hepatitis C virus (HCV) was shown to activate protein kinase R (PKR), which inhibits expression of interferon (IFN) and IFN-stimulated genes by controlling the translation of newly transcribed mRNAs. However, it is unknown exactly how HCV activates PKR. To address the molecular mechanism(s) of PKR activation mediated by HCV infection, we examined the effects of viral proteins on PKR activation. Here, we show that expression of HCV NS5B strongly induced PKR and eIF2α phosphorylation, and attenuated MHC class I expression. In contrast, expression of Japanese encephalitis virus RNA-dependent RNA polymerase did not induce phosphorylation of PKR. Co-immunoprecipitation analyses showed that HCV NS5B interacted with PKR. Furthermore, expression of NS5B with polymerase activity-deficient mutation failed to phosphorylate PKR, suggesting that RNA polymerase activity is required for PKR activation. These results suggest that HCV activates PKR by association with NS5B, resulting in translational suppression of MHC class I to establish chronic infection.

Vijayan S, Sidiq T, Yousuf S, et al.
Class I transactivator, NLRC5: a central player in the MHC class I pathway and cancer immune surveillance.
Immunogenetics. 2019; 71(3):273-282 [PubMed] Related Publications
Major histocompatibility complex (MHC) class I and class II molecules play critical roles in the activation of the adaptive immune system by presenting antigens to CD8+ and CD4+ T cells, respectively. Although it has been well known that CIITA (MHC class II transactivator), an NLR (nucleotide-binding domain, leucine-rich-repeat containing) protein, as a master regulator of MHC class II gene expression, the mechanism of MHC class I gene transactivation was unclear. Recently, another NLR protein, NLRC5 (NLR family, CARD domain-containing 5), was identified as an MHC class I transactivator (CITA). NLRC5 is a critical regulator for the transcriptional activation of MHC class I genes and other genes involved in the MHC class I antigen presentation pathway. CITA/NLRC5 plays a crucial role in human cancer immunity through the recruitment and activation of tumor killing CD8+ T cells. Here, we discuss the molecular function and mechanism of CITA/NLRC5 in the MHC class I pathway and its role in cancer.

Pan RY, Chung WH, Chu MT, et al.
Recent Development and Clinical Application of Cancer Vaccine: Targeting Neoantigens.
J Immunol Res. 2018; 2018:4325874 [PubMed] Free Access to Full Article Related Publications
Recently, increasing data show that immunotherapy could be a powerful weapon against cancers. Comparing to the traditional surgery, chemotherapy or radiotherapy, immunotherapy more specifically targets cancer cells, giving rise to the opportunities to the patients to have higher response rates and better quality of life and even to cure the disease. Cancer vaccines could be designed to target tumor-associated antigens (TAAs), cancer germline antigens, virus-associated antigens, or tumor-specific antigens (TSAs), which are also called neoantigens. The cancer vaccines could be cell-based (e.g., dendritic cell vaccine provenge (sipuleucel-T) targeting prostatic acid phosphatase for metastatic prostate cancer), peptide/protein-based, or gene- (DNA/RNA) based, with the different kinds of adjuvants. Neoantigens are tumor-specific and could be presented by MHC molecules and recognized by T lymphocytes, serving the ideal immune targets to increase the therapeutic specificity and decrease the risk of nonspecific autoimmunity. By targeting the shared antigens and private epitopes, the cancer vaccine has potential to treat the disease. Accordingly, personalized neoantigen-based immunotherapies are emerging. In this article, we review the literature and evidence of the advantage and application of cancer vaccine. We summarize the recent clinical trials of neoantigen cancer vaccines which were designed according to the patients' personal mutanome. With the rapid development of personalized immunotherapy, it is believed that tumors could be efficiently controlled and become curable in the new era of precision medicine.

Wang Y, Song X, Zheng Y, et al.
Cancer/testis Antigen MAGEA3 Interacts with STAT1 and Remodels the Tumor Microenvironment.
Int J Med Sci. 2018; 15(14):1702-1712 [PubMed] Free Access to Full Article Related Publications
Cancer-testis antigen MAGEA3, being restrictedly expressed in testis and various kinds of tumors, has long been considered as an ideal target for immunotherapy. In this study, we report that MAGEA3 interacts with STAT1 and regulates the expression of tyrosine phosphorylated STAT1 (pY-STAT1) in tumor cells. We show that pY-STAT1 is significantly up-regulated when MAGEA3 is silenced by MAGEA3-specific siRNA. RNA sequencing analysis identified 274 STAT1-related genes to be significantly altered in expression level in MAGEA3 knockdown cells. Further analysis of these differentially expressed genes with GO enrichment and KEGG pathway revealed that they are mainly enriched in plasma membrane, extracellular region and MHC class I protein complex, and involved in the interferon signaling pathways, immune response, antigen presentation and cell chemotaxis. The differentially expressed genes associated with chemokines, antigen presentation and vasculogenic mimicry formation were validated by biological experiments. Matrigel matrix-based tube formation assay showed that silencing MAGEA3 in tumor cells impairs tumor vasculogenic mimicry formation. These data indicate that MAGEA3 expression in tumor cells is associated with immune cells infiltration into tumor microenvironment and anti-tumor immune responses, implying that it may play an important role in tumor immune escape. Our findings reveal the potential impact of MAGEA3 on the immunosuppressive tumor microenvironment and will provide promising strategies for improving the efficacy of MAGEA3-targeted immunotherapy.

Conway JR, Kofman E, Mo SS, et al.
Genomics of response to immune checkpoint therapies for cancer: implications for precision medicine.
Genome Med. 2018; 10(1):93 [PubMed] Free Access to Full Article Related Publications
Immune checkpoint blockade (ICB) therapies, which potentiate the body's natural immune response against tumor cells, have shown immense promise in the treatment of various cancers. Currently, tumor mutational burden (TMB) and programmed death ligand 1 (PD-L1) expression are the primary biomarkers evaluated for clinical management of cancer patients across histologies. However, the wide range of responses has demonstrated that the specific molecular and genetic characteristics of each patient's tumor and immune system must be considered to maximize treatment efficacy. Here, we review the various biological pathways and emerging biomarkers implicated in response to PD-(L)1 and cytotoxic T lymphocyte-associated antigen 4 (CTLA-4) therapies, including oncogenic signaling pathways, human leukocyte antigen (HLA) variability, mutation and neoantigen burden, microbiome composition, endogenous retroviruses (ERV), and deficiencies in chromatin remodeling and DNA damage repair (DDR) machinery. We also discuss several mechanisms that have been observed to confer resistance to ICB, such as loss of phosphatase and tensin homolog (PTEN), loss of major histocompatibility complex (MHC) I/II expression, and activation of the indoleamine 2,3-dioxygenase 1 (IDO1) and transforming growth factor beta (TGFβ) pathways. Clinical trials testing the combination of PD-(L)1 or CTLA-4 blockade with molecular mediators of these pathways are becoming more common and may hold promise for improving treatment efficacy and response. Ultimately, some of the genes and molecular mechanisms highlighted in this review may serve as novel biological targets or therapeutic vulnerabilities to improve clinical outcomes in patients.

Luo D, Dong XW, Yan B, et al.
MG132 selectively upregulates MICB through the DNA damage response pathway in A549 cells.
Mol Med Rep. 2019; 19(1):213-220 [PubMed] Free Access to Full Article Related Publications
Natural killer (NK) cells recognize stress‑activated NK group 2, member D (NKG2D) ligands in tumors. In the present study, the expression levels of NKG2D ligands were examined in four lung cancer cell lines (A549, PLA801D, NCI‑H157 and NCI‑H520). In the A549 cells, the expression of MHC class I polypeptiderelated sequence (MIC)A/B and UL16 binding protein (ULBP)1 was weak, the expression of ULBP2 was typical, and neither ULBP3 nor ULBP4 were expressed. The mechanism underlying the regulatory effect of a cancer treatment agent on the expression of NKG2D ligands was investigated using the proteasome inhibitor MG132. Following treatment for 8 h with MG132, the transcription levels of MICB and ULBP1 were upregulated 10.62‑ and 11.09‑fold, respectively, and the expression levels of MICB and ULBP1 were increased by 68.18 and 23.65%, respectively. Notably, MICB exhibited significant time‑dependent change. MG132 increased the transcription of MICB by acting at a site in the 480‑bp MICB upstream promoter. The activity of the MICB promoter was upregulated 1.77‑fold following treatment with MG132. MG132 treatment improved the cytotoxicity of NK cells, which was partially blocked by an antibody targeting NKG2D, and more specifically the MICB molecule. The expression of MICB induced by MG132 was inhibited by KU‑55933 [ataxia telangiectasia mutated (ATM) kinase inhibitor], wortmannin (phosphoinositide 3 kinase inhibitor) and caffeine (ATM/ATM‑Rad3‑related inhibitor). The phosphorylation of checkpoint kinase 2 (Chk2), an event associated with DNA damage, was observed following treatment with MG132. These results indicated that MG132 selectively upregulates the expression of MICB in A549 cells, and increases the NKG2D‑mediated cytotoxicity of NK cells. The regulatory effect of MG132 may be associated with the activation of Chk2, an event associated with DNA damage. The combination of MG132 with NK cell immunotherapy may have a synergistic effect that improves the therapeutic effect of lung cancer treatment.

Triulzi T, Regondi V, De Cecco L, et al.
Early immune modulation by single-agent trastuzumab as a marker of trastuzumab benefit.
Br J Cancer. 2018; 119(12):1487-1494 [PubMed] Free Access to Full Article Related Publications
BACKGROUND: Optimising the selection of HER2-targeted regimens by identifying subsets of HER2-positive breast cancer (BC) patients who need more or less therapy remains challenging. We analysed BC samples before and after treatment with 1 cycle of trastuzumab according to the response to trastuzumab.
METHODS: Gene expression profiles of pre- and post-treatment tumour samples from 17 HER2-positive BC patients were analysed on the Illumina platform. Tumour-associated immune pathways and blood counts were analysed with regard to the response to trastuzumab. HER2-positive murine models with differential responses to trastuzumab were used to reproduce and better characterise these data.
RESULTS: Patients who responded to single-agent trastuzumab had basal tumour biopsies that were enriched in immune pathways, particularly the MHC-II metagene. One cycle of trastuzumab modulated the expression levels of MHC-II genes, which increased in patients who had a complete response on treatment with trastuzumab and chemotherapy. Trastuzumab increased the MHC-II-positive cell population, primarily macrophages, only in the tumour microenvironment of responsive mice. In patients who benefited from complete trastuzumab therapy and in mice that harboured responsive tumours circulating neutrophil levels declined, but this cell subset rose in nonresponsive tumours.
CONCLUSIONS: Short treatment with trastuzumab induces local and systemic immunomodulation that is associated with clinical outcomes.

Han X, Geng X, Li Z, et al.
The Relationship Between Phospho-p38, Matrix Metalloproteinase 9, and Major Histocompatibility Complex Class I Chain-Related Molecule A Expression in Pituitary Adenomas Demonstrates a New Mechanism of Pituitary Adenoma Immune Escape.
World Neurosurg. 2019; 123:e116-e124 [PubMed] Related Publications
BACKGROUND: The major histocompatibility complex class I chain-related molecule A (MICA) is one of the natural killer group 2D ligands. Soluble major histocompatibility complex class I chain-related molecule A (sMICA) mediates tumor immune escape, but the mechanism is not fully understood. In this study, we examined the expression of phospho-p38, matrix metalloproteinase 9 (MMP-9), and MICA and their relationships among each other in pituitary adenoma tissues to provide a histologic basis for the mechanism of pituitary adenoma immune escape.
METHODS: We applied immunohistochemistry, real-time quantitative reverse-transcriptase polymerase chain reaction, and Western blot to detect phospho-p38, MMP-9, and MICA expression at the mRNA and protein levels in pituitary adenoma tissues. Enzyme-linked immunosorbent assay was used to examine the expression levels of MMP-9 and sMICA in peripheral blood serum from patients with pituitary adenoma.
RESULTS: We found that p38, MICA, and MMP-9 mRNA levels were greater in pituitary adenomas than in normal tissues. The phospho-p38, MMP-9, and MICA proteins were overexpressed in pituitary adenomas, and the expression of MMP-9 and MICA were positively correlated with the expression of phospho-p38. In addition, the serum levels of sMICA and MMP-9 proteins in pituitary adenoma patients were significantly greater than those in normal controls.
CONCLUSIONS: These findings suggest that activation of the p38/mitogen-activated protein kinase pathway may increase MICA expression and induce MMP-9 expression. MMP-9 is involved in the shedding of sMICA from MICA to promote tumor immune escape. Furthermore, p38/mitogen-activated protein kinase could potentially represent a novel target for inhibiting pituitary adenoma immune escape.

Ti D, Niu Y, Wu Z, et al.
Genetic engineering of T cells with chimeric antigen receptors for hematological malignancy immunotherapy.
Sci China Life Sci. 2018; 61(11):1320-1332 [PubMed] Related Publications
The host immune system plays an instrumental role in the surveillance and elimination of tumors by recognizing and destroying cancer cells. In recent decades, studies have mainly focused on adoptive immunotherapy using engineered T cells for the treatment of malignant diseases. Through gene engraftment of the patient's own T cells with chimeric antigen receptor (CAR), they can recognize tumor specific antigens effectively and eradicate selectively targeted cells in an MHC-independent fashion. To date, CAR-T cell therapy has shown great clinical utility in patients with B-cell leukemias. Owing to different CAR designs and tumor complex microenvironments, genetically redirected T cells may generate diverse biological properties and thereby impact their long-term clinical performance and outcome. Meanwhile some unexpected toxicities that result from CAR-T cell application have been examined and limited the curative effects. Diverse important parameters are closely related with adoptively transferred cell behaviors, including CAR-T cells homing, CAR constitutive signaling, T cell differentiation and exhaustion. Thus, understanding CARs molecular design to improve infused cell efficacy and safety is crucial to clinicians and patients who are considering this novel cancer therapeutics. In this review, the developments in CAR-T cell therapy and the limitations and perspectives in optimizing this technology towards clinical application are discussed.

Watanabe S, Hayashi H, Haratani K, et al.
Mutational activation of the epidermal growth factor receptor down-regulates major histocompatibility complex class I expression via the extracellular signal-regulated kinase in non-small cell lung cancer.
Cancer Sci. 2019; 110(1):52-60 [PubMed] Free Access to Full Article Related Publications
The efficacy of programmed cell death-1 (PD-1) blockade in patients with non-small cell lung cancer (NSCLC) positive for epidermal growth factor receptor (EGFR) gene mutations has been found to be limited, but the underlying mechanisms for this poor response have remained obscure. Given that the recognition by T cells of tumor antigens presented by major histocompatibility complex class I (MHC-I) molecules is essential for an antitumor immune response, we examined the effects of EGFR tyrosine kinase inhibitors (TKIs) on MHC-I expression in NSCLC cell lines. Appropriate EGFR-TKIs increased MHC-I expression at the mRNA and cell surface protein levels in NSCLC cells positive for EGFR mutations including those with the T790M secondary mutation. Trametinib, an inhibitor of the extracellular signal-regulated kinase (ERK) kinase MEK, also increased MHC-I expression, whereas the phosphatidylinositol 3-kinase (PI3K) inhibitor buparlisib did not, suggesting that the MEK-ERK pathway mediates the down-regulation of MHC-I expression in response to EGFR activation. Immunohistochemical analysis of EGFR-mutated NSCLC specimens obtained before and after EGFR-TKI treatment also revealed down-regulation of phosphorylated forms of EGFR and ERK in association with up-regulation of MHC-I, an increased number of infiltrating CD8

Christopher MJ, Petti AA, Rettig MP, et al.
Immune Escape of Relapsed AML Cells after Allogeneic Transplantation.
N Engl J Med. 2018; 379(24):2330-2341 [PubMed] Free Access to Full Article Related Publications
BACKGROUND: As consolidation therapy for acute myeloid leukemia (AML), allogeneic hematopoietic stem-cell transplantation provides a benefit in part by means of an immune-mediated graft-versus-leukemia effect. We hypothesized that the immune-mediated selective pressure imposed by allogeneic transplantation may cause distinct patterns of tumor evolution in relapsed disease.
METHODS: We performed enhanced exome sequencing on paired samples obtained at initial presentation with AML and at relapse from 15 patients who had a relapse after hematopoietic stem-cell transplantation (with transplants from an HLA-matched sibling, HLA-matched unrelated donor, or HLA-mismatched unrelated donor) and from 20 patients who had a relapse after chemotherapy. We performed RNA sequencing and flow cytometry on a subgroup of these samples and on additional samples for validation.
RESULTS: On exome sequencing, the spectrum of gained and lost mutations observed with relapse after transplantation was similar to the spectrum observed with relapse after chemotherapy. Specifically, relapse after transplantation was not associated with the acquisition of previously unknown AML-specific mutations or structural variations in immune-related genes. In contrast, RNA sequencing of samples obtained at relapse after transplantation revealed dysregulation of pathways involved in adaptive and innate immunity, including down-regulation of major histocompatibility complex (MHC) class II genes ( HLA-DPA1, HLA-DPB1, HLA-DQB1, and HLA-DRB1) to levels that were 3 to 12 times lower than the levels seen in paired samples obtained at presentation. Flow cytometry and immunohistochemical analysis confirmed decreased expression of MHC class II at relapse in 17 of 34 patients who had a relapse after transplantation. Evidence suggested that interferon-γ treatment could rapidly reverse this phenotype in AML blasts in vitro.
CONCLUSIONS: AML relapse after transplantation was not associated with the acquisition of relapse-specific mutations in immune-related genes. However, it was associated with dysregulation of pathways that may influence immune function, including down-regulation of MHC class II genes, which are involved in antigen presentation. These epigenetic changes may be reversible with appropriate therapy. (Funded by the National Cancer Institute and others.).

Servín-Blanco R, Chávaro-Ortiz RM, Zamora-Alvarado R, et al.
Generation of cancer vaccine immunogens derived from major histocompatibility complex (MHC) class I molecules using variable epitope libraries.
Immunol Lett. 2018; 204:47-54 [PubMed] Related Publications
Although various immune checkpoint inhibitors (ICIs), used for the treatment of advanced cancer, showed remarkably durable tumor regression in a subset of patients, there are important limitations in a large group of non-responders, and the generation of novel immunogens capable of inducing protective cellular immune responses is a priority in cancer immunotherapy field. During the last decades, several types of vaccine immunogens have been used in numerous preclinical studies and clinical trials. However, although immunity to tumor Ags can be elicited by most vaccines tested, their clinical efficacy remains modest. Recently, we have developed an innovative vaccine concept, called Variable Epitope Libraries (VELs), with the purpose to exploit the high antigenic variability of many important pathogens and tumor cells as starting points for the construction of a new class of vaccine immunogens capable of inducing the largest possible repertoire of both B and T cells. In the present study, we decided to generate VEL immunogens derived from both classical and non-classical major histocompatibility complex (MHC) class I molecules. The MHC molecules, responsible for antigen presentation and subsequent activation of T lymphocytes, undergo multiple modifications that directly affect their proper function, resulting in immune escape of tumor cells. Two large VELs derived from multi-epitope region of H2-Kd and Qa-2 sequences (46 and 34 amino acids long, respectively), along with their wild type counterparts have been generated as synthetic peptides and tested in an aggressive 4T1 mouse model of breast cancer. Significant inhibition of tumor growth and the reduction of metastatic lesions in the lungs of immunized mice were observed. This study demonstrated for the first time the successful application of VELs carrying combinatorial libraries of epitope variants derived from MHC class I molecules as novel vaccine immunogens.

McCaw TR, Li M, Starenki D, et al.
The expression of MHC class II molecules on murine breast tumors delays T-cell exhaustion, expands the T-cell repertoire, and slows tumor growth.
Cancer Immunol Immunother. 2019; 68(2):175-188 [PubMed] Article available free on PMC after 01/02/2020 Related Publications
The expression of MHC class II molecules (MHCII) on tumor cells correlates with survival and responsiveness to immunotherapy. However, the mechanisms underlying these observations are poorly defined. Using a murine breast tumor line, we showed that MHCII-expressing tumors grew more slowly than controls and recruited more functional CD4

Consonni M, Dellabona P, Casorati G
Potential advantages of CD1-restricted T cell immunotherapy in cancer.
Mol Immunol. 2018; 103:200-208 [PubMed] Related Publications
Adoptive cell therapy (ACT) using tumor-specific "conventional" MHC-restricted T cells obtained from tumor-infiltrating lymphocytes, or derived ex vivo by either antigen-specific expansion or genetic engineering of polyclonal T cell populations, shows great promise for cancer treatment. However, the wide applicability of this therapy finds limits in the high polymorphism of MHC molecules that restricts the use in the autologous context. CD1 antigen presenting molecules are nonpolymorphic and specialized for lipid antigen presentation to T cells. They are often expressed on malignant cells and, therefore, may represent an attractive target for ACT. We provide a brief overview of the CD1-resticted T cell response in tumor immunity and we discuss the pros and cons of ACT approaches based on unconventional CD1-restricted T cells.

Dow M, Pyke RM, Tsui BY, et al.
Integrative genomic analysis of mouse and human hepatocellular carcinoma.
Proc Natl Acad Sci U S A. 2018; 115(42):E9879-E9888 [PubMed] Article available free on PMC after 01/02/2020 Related Publications
Cancer genomics has enabled the exhaustive molecular characterization of tumors and exposed hepatocellular carcinoma (HCC) as among the most complex cancers. This complexity is paralleled by dozens of mouse models that generate histologically similar tumors but have not been systematically validated at the molecular level. Accurate models of the molecular pathogenesis of HCC are essential for biomedical progress; therefore we compared genomic and transcriptomic profiles of four separate mouse models [MUP transgenic, TAK1-knockout, carcinogen-driven diethylnitrosamine (DEN), and Stelic Animal Model (STAM)] with those of 987 HCC patients with distinct etiologies. These four models differed substantially in their mutational load, mutational signatures, affected genes and pathways, and transcriptomes. STAM tumors were most molecularly similar to human HCC, with frequent mutations in

Zhu J, Li Y, Li L, et al.
A novel absorption spectrometric method, based on graphene nanomaterials, for detection of hepatocellular carcinoma-specific T lymphocyte cells.
Int J Nanomedicine. 2018; 13:5523-5536 [PubMed] Article available free on PMC after 01/02/2020 Related Publications
Introduction: Detection of antigen-specific cytotoxic T lymphocytes (CTLs) is the foundation for understanding hepatocellular carcinoma immune pathology and hepatocellular carcinoma immunotherapy. However, the classical method for labeling CTLs, major histocompatibility complex (MHC)-peptide tetramer, has drawbacks and needs further improvement.
Materials and methods: Here, as a new detection probe, a graphene-based MHC-peptide multimer was developed for sensitively and selectively identifying hepatocellular carcinoma-specific T-cells. To assess its detection efficiency, reduced graphene oxide (RGO) was functionalized with hemin and streptavidin to prepare a functionalized HRGO-streptavidin complex. Biotinylated MHC-peptide monomer was subsequently constructed onto HRGO to generate a detection probe for CTL labeling. The number of T-cells was detected through the reaction between HRGO and tetramethylbenzidine.
Results: Using HRGO/MHC-peptide multimers, the number of T-cells was efficiently detected in both the induction system in vitro and in peripheral blood of patients.
Conclusion: HRGO/MHC-peptide multimers methodology has application prospects in the detection of antigen peptide-specific T cells.

Johnson JK, Wright PW, Li H, Anderson SK
Identification of trophoblast-specific elements in the HLA-C core promoter.
HLA. 2018; 92(5):288-297 [PubMed] Article available free on PMC after 01/11/2019 Related Publications
There are several aspects of HLA-C gene expression that distinguish it from the HLA-A and HLA-B genes. First, HLA-C is expressed by extravillous trophoblasts, whereas HLA-A and HLA-B are not. Second, its cell-surface expression is much lower, which has been linked to changes in transcription and efficiency of peptide loading and export. Third, HLA-C possesses a NK cell-specific promoter and a complex alternative splicing system that regulates expression during NK cell development. In this study, we investigate the contribution of the HLA-C core promoter to trophoblast-specific expression. Analysis of transcription start sites showed the presence of a trophoblast-associated start site and additional upstream TATA and CCAAT-box elements in the HLA-C promoter, suggesting the presence of an overlapping trophoblast-specific promoter. A comparison of in vitro promoter activity showed that the HLA-C promoter was more active in trophoblast cell lines than either the HLA-A or HLA-B promoters. Enhanced trophoblast activity was mapped to the central enhanceosome region of the promoter, and mutational analysis identified changes in the RFX-binding region that generated a trophoblast-specific enhancer.

Ferreiro-Iglesias A, Lesseur C, McKay J, et al.
Fine mapping of MHC region in lung cancer highlights independent susceptibility loci by ethnicity.
Nat Commun. 2018; 9(1):3927 [PubMed] Article available free on PMC after 01/11/2019 Related Publications
Lung cancer has several genetic associations identified within the major histocompatibility complex (MHC); although the basis for these associations remains elusive. Here, we analyze MHC genetic variation among 26,044 lung cancer patients and 20,836 controls densely genotyped across the MHC, using the Illumina Illumina OncoArray or Illumina 660W SNP microarray. We impute sequence variation in classical HLA genes, fine-map MHC associations for lung cancer risk with major histologies and compare results between ethnicities. Independent and novel associations within HLA genes are identified in Europeans including amino acids in the HLA-B*0801 peptide binding groove and an independent HLA-DQB1*06 loci group. In Asians, associations are driven by two independent HLA allele sets that both increase risk in HLA-DQB1*0401 and HLA-DRB1*0701; the latter better represented by the amino acid Ala-104. These results implicate several HLA-tumor peptide interactions as the major MHC factor modulating lung cancer susceptibility.

Planelles D, Balas A, Caro JL, et al.
HLA-B*56:55:01:02, -C*03:374 and -DPB1*13:01:03 characterized by next-generation sequencing.
HLA. 2018; 92(6):419-420 [PubMed] Related Publications
The new HLA alleles HLA-B*56:55:01:02, -C*03:374 and -DPB1*13:01:03 were characterized by NGS methodology.

Paulson KG, Voillet V, McAfee MS, et al.
Acquired cancer resistance to combination immunotherapy from transcriptional loss of class I HLA.
Nat Commun. 2018; 9(1):3868 [PubMed] Article available free on PMC after 01/11/2019 Related Publications
Understanding mechanisms of late/acquired cancer immunotherapy resistance is critical to improve outcomes; cellular immunotherapy trials offer a means to probe complex tumor-immune interfaces through defined T cell/antigen interactions. We treated two patients with metastatic Merkel cell carcinoma with autologous Merkel cell polyomavirus specific CD8+ T cells and immune-checkpoint inhibitors. In both cases, dramatic remissions were associated with dense infiltration of activated CD8+s into the regressing tumors. However, late relapses developed at 22 and 18 months, respectively. Here we report single cell RNA sequencing identified dynamic transcriptional suppression of the specific HLA genes presenting the targeted viral epitope in the resistant tumor as a consequence of intense CD8-mediated immunologic pressure; this is distinguished from genetic HLA-loss by its reversibility with drugs. Transcriptional suppression of Class I loci may underlie resistance to other immunotherapies, including checkpoint inhibitors, and have implications for the design of improved immunotherapy treatments.

Tong WL, Callahan BM, Tu YN, et al.
Immune receptor recombinations from breast cancer exome files, independently and in combination with specific HLA alleles, correlate with better survival rates.
Breast Cancer Res Treat. 2019; 173(1):167-177 [PubMed] Related Publications
PURPOSE: Immune characterizations of cancers, including breast cancer, have led to information useful for prognoses and are considered to be important in the future of refining the use of immunotherapies, including immune checkpoint inhibitor therapies. In this study, we sought to extend these characterizations with genomics approaches, particularly with cost-effective employment of exome files.
METHODS: By recovery of immune receptor recombination reads from the cancer genome atlas (TCGA) breast cancer dataset, we observed associations of these recombinations with T-cell and B-cell biomarkers and with distinct survival rates.
RESULTS: Recovery of TRD or IGH recombination reads was associated with an improved disease-free survival (p = 0.047 and 0.045, respectively). Determination of the HLA types using the exome files allowed matching of T-cell receptor V- and J-gene segment usage with specific HLA alleles, in turn allowing a refinement of the association of immune receptor recombination read recoveries with survival. For example, the TRBV7, HLA-C*07:01 combination represented a significantly worse, disease-free outcome (p = 0.014) compared to all other breast cancer samples. By direct comparisons of distinct TRB gene segment usage, HLA allele combinations revealed breast cancer subgroups, within the entire TCGA breast cancer dataset with even more dramatic survival distinctions.
CONCLUSIONS: In sum, the use of exome files for recovery of adaptive immune receptor recombination reads, and the simultaneous determination of HLA types, has the potential of advancing the use of immunogenomics for immune characterization of breast tumor samples.

Disclaimer: This site is for educational purposes only; it can not be used in diagnosis or treatment.

Cite this page: Cotterill SJ. HLA-C, Cancer Genetics Web: http://www.cancer-genetics.org/HLA-C.htm Accessed:

Creative Commons License
This page in Cancer Genetics Web by Simon Cotterill is licensed under a Creative Commons Attribution-ShareAlike 4.0 International License.
Note: content of abstracts copyright of respective publishers - seek permission where appropriate.

 [Home]    Page last revised: 31 August, 2019     Cancer Genetics Web, Established 1999