Sperm protein 17 is a novel cancer-testis antigen in multiple myeloma

Blood ◽  
2001 ◽  
Vol 97 (5) ◽  
pp. 1508-1510 ◽  
Author(s):  
Seah H. Lim ◽  
Zhiqing Wang ◽  
Maurizio Chiriva-Internati ◽  
Yuying Xue
Keyword(s):  
Multiple Myeloma ◽  
Blot Analysis ◽  
Tumor Antigens ◽  
Tissue Expression ◽  
Rt Pcr ◽  
Aberrant Expression ◽  
Ct Antigen ◽  
Ct Antigens ◽  
Cancer Testis

Various studies have demonstrated the aberrant expression of normal testicular proteins in neoplastic cells. These proteins collectively form the new class of tumor antigens called cancer-testis (CT) antigens. Their selective normal tissue expression makes them ideal antigens for immune targeting of the malignant disease. In this study, the expression of a spermatozoa protein, Sp17, in multiple myeloma was investigated. It was found that Sp17 is detectable in tumor cells from 12 of 47 (26%) myeloma patients. Reverse transcription polymerase chain reaction (RT-PCR) and Western blot analysis detected Sp17 transcripts and proteins, respectively. Northern blot analysis and RT-PCR demonstrated that Sp17 transcripts were detected only in normal testis, supporting its tissue specificity. Since a high proportion of normal individuals develop antibodies against Sp17 following vasectomy, Sp17 is likely to be a highly immunogenic protein in vivo. Sp17 is therefore a novel member of the CT antigen family and should be an ideal target for immunotherapy of multiple myeloma.

Alloreactivity as a Source of High Avidity T Cell Clones Specific for Cancer Testis-Antigens Associated with Multiple Myeloma: Prospects for Adoptive Immunotherapy with Primary T Cells Redirected toward Multiple Myeloma by T Cell Receptor Gene Transfer.

Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 3712-3712
Author(s):  
Holger Kronig ◽  
Kathrin Hofer ◽  
Julia Neudorfer ◽  
Christian Peschel ◽  
Helga Bernhard
Keyword(s):  
Multiple Myeloma ◽  
T Cells ◽  
T Cell ◽  
T Cell Receptor ◽  
Cell Receptor ◽  
High Avidity ◽  
Peptide Epitopes ◽  
Ct Antigen ◽  
Ct Antigens ◽  
Cancer Testis

Abstract Cancer testis (CT)-antigens belong to a class of tumor antigens that are aberrantly expressed in a variety of hematological malignancies including multiple myeloma. Owing to their restricted gene expression, CT-antigens represent potential target antigens for immunotherapeutical approaches such as vaccination and adoptive T cell transfer. As the CT-antigens are self antigens, the majority of CT-antigen-specific autologous T cells display a low avidity T cell receptor (TCR), which often results in a weak tumor recognition efficiency. Our group has been focusing on the isolation of highly avid T cells against CT-antigens that are expressed in multiple myeloma, in particular MAGE-C1, MAGE-C2, and NY-ESO-1. The experimental approach was based on the stimulation of allo-restricted cytotoxic T cells, because highly avid T cells recognizing peptide epitopes in context with foreign HLA-alleles are not depleted in the thymus. HLA-A2-negative T cells were stimulated with HLA-A2-positive allogeneic dendritic cells that had been exogenously loaded with HLA-A2-binding peptides derived from NY-ESO-1, MAGE-C1 or MAGE-C2. Using this technique we were able to isolate allo-HLA-A2-restricted cytotoxic T lymphocyte (CTL) clones with peptide-dominant binding against known and novel peptide epitopes derived from NY-ESO-1, MAGE-C1 and MAGE-C2. The expanded peptide-specific CTL clones lysed HLA-A2-positive myeloma cell lines expressing NY-ESO-1, MAGE-C1 and MAGE-C2, respectively. Of note, the MAGE-C1-specific T cells crossreacted with the corresponding MAGE-C2 peptide due to the existing sequence homology between MAGE-C1 and MAGE-C2. Current experiments focus on redirecting primary T cells toward myeloma cells by retroviral gene transfer of CT-antigen-specific TCRs. The establishment of a set of high avidity TCRs specific for CT-antigens facilitates the development of adoptive transfer regimens based on TCR-transduced T cells for the treatment of multiple myeloma.

Successful Isolation of Novel Cancer-Testis Antigens Suitable for Immunotherapy of Hematologic Malignancies Using a Yeast Two-Hybrid System in a Testicular cDNA Library.

Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 1215-1215
Author(s):  
Farouk Meklat ◽  
Wei Li ◽  
Zhiqing Wang ◽  
Yana Zhang ◽  
Jian Zhang ◽  
...  
Keyword(s):  
Tumor Cells ◽  
Cdna Library ◽  
Normal Tissue ◽  
Hematologic Malignancies ◽  
Tissue Expression ◽  
Aberrant Expression ◽  
Interacting Protein ◽  
Ct Antigen ◽  
Ct Antigens ◽  
Protamine 1

Abstract Most intracellular proteins are expressed with their interacting ligands. If a protein shows restricted normal tissue expression, its interacting ligand will likely also follow a restricted normal tissue expression pattern. We hypothesized that protein molecules interacting with CT antigens may also be testicular restricted and potential CT antigens. Identification of these proteins provides the opportunity for their application in polyvalent tumor vaccines to overcome the problems associated with antigen heterogeneity within a tumor specimen. We have applied two known CT antigens, Sperm protein 17 (Sp17) and SEMG1, as baits in yeast two-hybrid systems of a testicular cDNA library to identify the protein interacting with these two antigens and determine whether the interacting protein are also CT antigens. To do so, we first isolated and amplified cDNA encoding Sp17 and SEMG1. Following successful amplification and sequence confirmation, the cDNAs were sub-cloned into pGBKT7 and transformed into yeast strain AH109 and selected on SD/-Trp plates. Mating was performed between AH109-pGBKT7-Sp17 or pGBKT7-SEMG 1 and pre-transformed human testis cDNA library in yeast strain Y187. Following mating, the culture was first selected on SD/-His/-Leu/-Trp plates and then on SD/-Ade/-His/-Leu/-Trp/X-a -Gal plates. A total of 17 positive clones were isolated using Sp17 and 24 positive clones using SEMG 1 as the bait. Following confirmation of interaction, the colonies were expanded and the the plasmids subjected to sequence identification by nucleotide analysis. All 17 clones isolated using Sp17 encoded Ropporin 1 and all 24 clones isolated using SEMG 1 encoded Protamine 1. Using RT-PCR on total RNA derived from a panel of normal tissues, we demonstrated the very restriction normal tissue expression of Protamine 1 and Ropporin 1, being present only in normal testis, indicating that they are also testicular-specific genes. Analysis of a panel of fresh tumor cells, we showed the aberrant expression of both Protamine 1 and Ropporin 1 in a proportion of hematologic malignancies, including acute myeloid leukemia, multiple myeloma and chronic lymphocytic leukemia, supporting the notion that Ropporin 1 and Protamine 1 are both novel CT antigens in hematologic malignancies. Furthermore, these antigens were also able to elicit high titer B-cell responses in vivo in these patients, suggesting their immunogenicity in the autologous host, even in cancer-bearing patients. Interestingly, the expression of one partner CT antigen within an individual tumor specimen does not necessary predict for the co-expression of the interacting CT antigen. In conclusion, we have described a novel approach to the identification of CT antigens that could be used for immune targeting. This approach could be applied using other known CT antigens to identify other tumor antigens. The lack of a good correlation between the expressions of the partner protein with the interacting protein suggests two important points. First, the aberrant expression of these interacting pair of molecules is not a result of coordinated intracellular regulatory mechanisms but likely due to random processes. Second, if the function of one protein is dependent on the presence of its ligand, then these individual molecules expressed within the tumor cells are unlikely to be of any functional significance in the tumor cells from most patients.

scholarly journals Cancer/Testis Antigen MAGE-C1/CT7: New Target for Multiple Myeloma Therapy

2012 ◽  
Vol 2012 ◽  
pp. 1-7 ◽  
Author(s):  
Fabricio de Carvalho ◽  
André L. Vettore ◽  
Gisele W. B. Colleoni
Keyword(s):  
Multiple Myeloma ◽  
Tumor Antigens ◽  
Plasma Cells ◽  
Drug Induced ◽  
Aberrant Expression ◽  
Functional Studies ◽  
Cancer Testis Antigens ◽  
Somatic Tissues ◽  
Induced Apoptosis ◽  
Cancer Testis

Cancer/Testis Antigens (CTAs) are a promising class of tumor antigens that have a limited expression in somatic tissues (testis, ovary, fetal, and placental cells). Aberrant expression of CTAs in cancer cells may lead to abnormal chromosome segregation and aneuploidy. CTAs are regulated by epigenetic mechanisms (DNA methylation and acetylation of histones) and are attractive targets for immunotherapy in cancer because the gonads are immune privileged organs and anti-CTA immune response can be tumor-specific. Multiple myeloma (MM) is an incurable hematological malignancy, and several CTAs have been detected in many MM cell lines and patients. Among CTAs expressed in MM we must highlight theMAGE-C1/CT7located on the X chromosome and expressed specificity in the malignant plasma cells. MAGE-C1/CT7 seems to be related to disease progression and functional studies suggests that this CTA might play a role in cell cycle and mainly in survival of malignant plasma cells, protecting myeloma cells against spontaneous as well as drug-induced apoptosis.

Cancer-Testis (CT) Antigen Expression In AL Amyloidosis

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 4055-4055
Author(s):  
Michael A. Rosenzweig ◽  
Heather Landau ◽  
Achim A Jungbluth ◽  
Nicole Hanson ◽  
Denise Frosina ◽  
...  
Keyword(s):  
Multiple Myeloma ◽  
Cell Proliferation ◽  
Plasma Cell ◽  
Research Funding ◽  
Plasma Cells ◽  
Organ Involvement ◽  
Al Amyloidosis ◽  
Ct Antigen ◽  
Ct Antigens ◽  
Cancer Testis

Abstract Abstract 4055 Cancer-testis (CT) antigens are a family of proteins normally expressed in immune privileged sites such as testicular germ cells and placenta, but are overexpressed in various malignant tumors (Scanlan et al. Immunological Rev. 2002). CT antigens are therefore useful markers of malignancy as well as potential targets for antigen specific cancer immunotherapy. In multiple myeloma, CT 7, CT10 and MAGE-A are homogenously expressed in up to 75% of cases, and their expression increases with disease stage and cell proliferation (Jungbluth et al. Blood, 2005). In addition, CT-7 and MAGE-A3 play a role in plasma cell proliferation and chemosensitivity (Atanackovic et al. Haematologica 2010). Immunogenicity of CT antigens is evidenced by spontaneous humoral responses against CT antigens in patients with multiple myeloma (Cohen et al. ASH abstract 2008). In addition, anti-CT antigen immune responses of donor derived T and B cells have been reported following allogeneic stem cell transplantation, suggesting CT antigens may serve as a natural target for a graft-versus myeloma effect (Atanackovic et al. Blood 2007). Systemic light-chain (AL) amyloidosis is a plasma cell dyscrasia related to multiple myeloma characterized by small numbers of non-proliferating, clonogenic plasma cells producing pathologic light chains. In this study, we investigated the expression of several CT antigens in patients with AL amyloidosis to identify potential targets for immunotherapy and determine their prognostic significance. Methods: Fifteen cases of AL amyloidosis were studied employing standard IHC techniques on paraffin-embedded archival tissues. Presence of plasma cells was verified by CD138 immunostain. The following monoclonal antibodies (to the following CT Antigens) were used: mAb MA454 (MAGE-A1), 6C1 (several MAGE-A antigens), 57B (MAGE-A4), E978 (NY-ESO-1), CT7-33(CT7), CT10#5 (CT10), #26 (GAGE). Immunopositivity was graded based on the amount of IHC-positive plasma cells. Results: All 15 patients had a confirmed diagnosis of AL amyloidosis with an average plasma cell burden of 12.7% of the cells in the marrow. Eighty-seven percent (13/15) had lambda disease and 13% (2/15) kappa disease. Organ involvement included kidney (n=7)), heart (n=8), peripheral nervous system (n=2), and GI/liver (n=2). Five patients (33%) had multi-organ involvement. All patients were treated uniformly with risk-adapted melphalan as their initial therapy. CT7 was present in 9/15 (60%) while CT10 was demonstrated in only 1/15 AL amyloid cases. Plasma cells did not stain with any other anti-CT mAb. There were no significant differences with regard to organ involvement, response to treatment or prognosis and CT antigen positivity in this small sample set. Discussion: This is the first study identifying CT7 as the prevalent CT antigen in plasma cells of patients with AL amyloidosis. The almost exclusive presence of CT7 in AL amyloidosis may have clinical significance. Further studies are planned on additional samples to confirm the prevalence of CT7 expression in AL amyloidosis, determine its immunogenicity and further investigate prognostic implications. Additional studies are needed to determine the biology of CT antigens in AL amyloidosis and their value as a potential target for immunotherapy. Disclosures: Comenzo: Millenium Pharmaceuticals: Membership on an entity's Board of Directors or advisory committees; Elan Pharmaceuticals: Consultancy; Genzyme: Research Funding; Celgene: Research Funding; Ortho: Research Funding.

The cancer-testis antigens CT7 (MAGE-C1) and MAGE-A3/6 are commonly expressed in multiple myeloma and correlate with plasma-cell proliferation

Blood ◽  
2005 ◽  
Vol 106 (1) ◽  
pp. 167-174 ◽  
Author(s):  
Achim A. Jungbluth ◽  
Scott Ely ◽  
Maurizio DiLiberto ◽  
Ruben Niesvizky ◽  
Barbara Williamson ◽  
...  
Keyword(s):  
Multiple Myeloma ◽  
Cell Proliferation ◽  
Plasma Cell ◽  
Messenger Rna ◽  
Plasma Cells ◽  
Stage Iii ◽  
Ct Antigen ◽  
Ct Antigens ◽  
Novel Therapeutic Strategies ◽  
Cancer Testis

Multiple myeloma is a malignancy of plasma cells. Vaccine immunotherapy is among the novel therapeutic strategies under investigation for this disease. To identify myeloma-associated antigens as potential targets for vaccine immunotherapy, we surveyed a comprehensive panel of bone marrow specimens from patients with monoclonal gammopathy of undetermined significance (MGUS) and multiple myeloma for expression of cancer-testis (CT) antigens. Immunohistochemistry (IHC) demonstrated that 82% of stage-III myeloma specimens expressed the CT antigen CT7 (also known as melanoma antigen C1 [MAGE-C1]) and 70% expressed MAGE-A3/6. Messenger RNA for CT7 and MAGE-A family members was detected in 87% and 100% of stage-III samples, respectively. CT7 protein expression increased with advanced stage of disease. Higher levels of CT7 and MAGE-A3/6 proteins also correlated with elevated plasma-cell proliferation. These results show that CT7 and MAGE-A3/6 are promising myeloma-associated antigens for application in vaccine immunotherapy. Furthermore, the common expression and correlation with proliferation suggest a possible pathogenic role for these proteins in myeloma.

Longitudinal Analysis of Cancer-Testis Antigen Expression in Multiple Myeloma.

Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 4826-4826
Author(s):  
Djordje Atanackovic ◽  
Tim Luetkens ◽  
Julia Arfsten ◽  
Katrin Bartels ◽  
York Hildebrandt ◽  
...  
Keyword(s):  
Multiple Myeloma ◽  
Stem Cell ◽  
Stem Cell Transplantation ◽  
Longitudinal Analysis ◽  
Antigen Expression ◽  
Tumor Load ◽  
Ct Antigen ◽  
Ct Antigens ◽  
Over Time ◽  
Cancer Testis

Abstract BACKGROUND: Based on their immunogenicity and restricted tissue expression, cancer-testis (CT) antigens seem ideal targets for active immunotherapies. We have recently reported a frequent expression of CT antigens in multiple myeloma (Blood2007;109:1103–12). However, CT antigen expression has not been examined over time in patients with multiple myeloma (MM) or other malignancies. This seems surprising, since data on the persistence of CT antigen expression are needed in order to evaluate their usefulness as diagnostic markers and targets of immunotherapeutic approaches, especially in the case of minimal residual disease (MRD). METHODS: We analyzed 336 bone marrow (BM) samples obtained from 130 myeloma patients for expression of CT antigens. Samples of 41 healthy BM donors were used as controls. Expression of MAGEC1/CT7, MAGEC2/CT10, MAGEA3, and SSX2 was examined using qualitative RT-PCR. Real-time PCR was applied to quantify MAGEC1/CT7 expression over time. RESULTS: In MM patients with significant tumor load (>= 10% BM plasma cells), MAGEC1/CT7 was expressed in 69%, MAGEA3 in 55%, MAGEC2/CT10 in 44%, and SSX2 in 14% of samples. CT antigens were not expressed in healthy BM. Since expression of the remaining CT antigens was rarely observed without expression of MAGEC1/CT7, this CT antigen seemed to fulfill a ‘gatekeeper’ function. Expression of CT antigens correlated positively with clinical stage and was increased in recurrent disease compared to newly diagnosed MM. Noticeably, 76% of samples from patients who had not responded to therapy, 28% of samples from patients in partial remission, and only 8% of patients in complete remission expressed at least one CT antigen. Samples of patients who had received chemotherapy alone more frequently expressed CT antigens than samples of patients post autologous stem cell transplantation. The lowest frequency of CT antigen expression was observed in patients post allogeneic stem cell transplantation. Remarkably, in case a patient with significant tumor load had expressed a CT antigen once, 97% (MAGEC1/CT7), 88% (SSX2), 81% (MAGEA3), 67% (MAGEC2/CT10) of the subsequent BM samples of the same patient were positive for the respective antigen. When we analyzed 22 MM patients with at least three consecutive BM samples (median follow-up 21 months [range 4–35 months]) longitudinally and quantitatively for CT antigen expression, we observed a correlation between the BM expression of CT7/MAGEC1 mRNA and the clinical course of the disease as indicated by BM plasma cell infiltration (r=0.51, p<0.01) and, even more significantly, serum paraprotein levels (r=0.73, p<0.01). CONCLUSIONS: Performing the first longitudinal analysis of CT antigen expression in a human cancer, we demonstrate that in myeloma patients expression of MAGEC1/CT7, SSX2, MAGEA3, and MAGEC2/CT10 persists over time and represents an independent tumor marker. These findings suggest that downregulation of CT antigen expression is not a common tumor escape mechanism in myeloma and that CT antigens might, therefore, serve as diagnostic markers and targets for active immunotherapy, i.e. in the clinical setting of MRD.

scholarly journals HNRNPA2B1 promotes multiple myeloma progression by increasing AKT3 expression via m6A-dependent stabilization of ILF3 mRNA

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Fengjie Jiang ◽  
Xiaozhu Tang ◽  
Chao Tang ◽  
Zhen Hua ◽  
Mengying Ke ◽  
...  
Keyword(s):  
Multiple Myeloma ◽  
Cell Proliferation ◽  
Cellular Proliferation ◽  
Aberrant Expression ◽  
The Stability ◽  
Induced Apoptosis ◽  
Proliferation In Vitro

AbstractN6-methyladenosine (m6A) modification is the most prevalent modification in eukaryotic RNAs while accumulating studies suggest that m6A aberrant expression plays an important role in cancer. HNRNPA2B1 is a m6A reader which binds to nascent RNA and thus affects a perplexing array of RNA metabolism exquisitely. Despite unveiled facets that HNRNPA2B1 is deregulated in several tumors and facilitates tumor growth, a clear role of HNRNPA2B1 in multiple myeloma (MM) remains elusive. Herein, we analyzed the function and the regulatory mechanism of HNRNPA2B1 in MM. We found that HNRNPA2B1 was elevated in MM patients and negatively correlated with favorable prognosis. The depletion of HNRNPA2B1 in MM cells inhibited cell proliferation and induced apoptosis. On the contrary, the overexpression of HNRNPA2B1 promoted cell proliferation in vitro and in vivo. Mechanistic studies revealed that HNRNPA2B1 recognized the m6A sites of ILF3 and enhanced the stability of ILF3 mRNA transcripts, while AKT3 downregulation by siRNA abrogated the cellular proliferation induced by HNRNPA2B1 overexpression. Additionally, the expression of HNRNPA2B1, ILF3 and AKT3 was positively associated with each other in MM tissues tested by immunohistochemistry. In summary, our study highlights that HNRNPA2B1 potentially acts as a therapeutic target of MM through regulating AKT3 expression mediated by ILF3-dependent pattern.

The Spermatozoa Protein, SLLP1, Is a Novel Cancer-Testis Antigen in Hematologic Malignancies.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 4281-4281
Author(s):  
Zhiqing Wang ◽  
Yana Zhang ◽  
Arabinda Mandal ◽  
Jian Zhang ◽  
Francis J. Giles ◽  
...  
Keyword(s):  
Immune Responses ◽  
Western Blot ◽  
Tumor Cells ◽  
Blot Analysis ◽  
Western Blot Analysis ◽  
Hematologic Malignancies ◽  
Myeloma Cell ◽  
Rt Pcr ◽  
Healthy Donors ◽  
Cancer Testis

Abstract SLLP1 is a unique non-bacteriolytic c-lysozyme-like protein isolated from human spermatozoa. Antisera to SLLP1 blocks binding in the hamster egg penetration assay, suggesting that SLLP1 may be involved in sperm/egg adhesion. A recent study by dot blot analysis on RNA showed that SLLP1 was expressed only in the testis and in Burkitt lymphoma Raji cell line, suggesting that further studies are warranted to determine and characterize SLLP1 expression in tumor cells, in particular, fresh tumor specimens. Using a pair of sequence-specific primers in RT-PCR, we found that SLLP1 transcripts could be detected in 5/8 myeloma cell lines, suggesting that SLLP1 may be expressed in tumor cells from some hematologic malignancies. When we applied the investigations to 52 primary hematologic malignant specimens, SLLP1 transcripts were detected in 6/17 myeloma, 4/14 CML, 3/11 CLL, 2/9 AML and 0/1 hairy cell leukemia. In contrast, SLLP1 transcripts were not detected in the peripheral blood (n=12) or bone marrow (n=3) from any healthy donors. The specificity of the PCR products was confirmed by either sequence analysis or restriction digest with Pvu II. SLLP1 transcripts were translated into its corresponding protein in these tumor cells. Using tumor cell lysate in Western blot analysis, we detected SLLP1 protein in the myeloma cell lines and also in fresh malignant specimens, although positivities were only observed in specimens with high RT-PCR signals. All PCR-negative specimens were also negative in Western blot analysis. The specificity of the Western blot signals were confirmed in all cases by blocking assays with a high concentration of recombinant SLLP1 protein. We next investigated the expression of SLLP1 in a large panel of normal tissues using RT-PCR and real time quantitative PCR. Both approaches showed that SLLP1 is a novel Cancer-Testis antigen in hematologic malignancies. SLLP1 was detected, at a level of 8206 copies/0.25 mcg total RNA, only in normal testis. We also found that the SLLP1 mRNA copy numbers in fresh hematologic tumor specimens were up to 2316 copies/0.25 mcg total RNA, i.e. more than 25% of the level found in normal testis. We cloned and generated SLLP1 recombinant protein from E coli and used the purified recombinant SLLP1 in an ELISA system to detect anti-SLLP1 antibodies. Using sera from 24 healthy donors and the mean + 2SD as the cut-off signal intensities, we found that high titer IgG antibodies directed at SLLP1 could be detected in the sera from 2/9 AML, 5/23 CLL, 6/27 CML and 14/51 myeloma patients. The specificity of the antibodies was confirmed in Western blot analysis. Probably due to the decreased sensitivity of the detection system in Western blot analysis, only 1/2 AML, 3/5 CLL, 4/6 CML and 7/14 myeloma SLLP1 antibody+ sera produced a signal in the Western blot analysis. Interesting, IgG2 was by far the commonest SLLP1 antibodies in these patients. There was a good correlation between SLLP1 gene expression and immune responses. In summary, SLLP1 is a novel CT antigen in hematologic malignancies and is capable of eliciting B-cell immune responses in vivo in cancer-bearing patients. Our results support SLLP1 as a protein target appropriate for further in vitro study to define its suitability for immunotherapy.

scholarly journals The testis protein ZNF165 is a SMAD3 cofactor that coordinates oncogenic TGFβ signaling in triple-negative breast cancer

2020 ◽  
Author(s):  
Zane A. Gibbs ◽  
Luis C. Reza ◽  
Chun-Chun Cheng ◽  
Jill M. Westcott ◽  
Kathleen McGlynn ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Triple Negative Breast Cancer ◽  
Triple Negative ◽  
Transforming Growth Factor ◽  
Zinc Finger Protein ◽  
Transforming Growth Factor Β ◽  
Aberrant Expression ◽  
Growth And Survival ◽  
Ct Antigens

ABSTRACTCancer/testis (CT) antigens are proteins whose expression is normally restricted to germ cells yet aberrantly activated in tumors, where their functions remain relatively cryptic. Here we report that ZNF165, a CT antigen frequently expressed in triple-negative breast cancer (TNBC), associates with SMAD3 to modulate transcription of transforming growth factor β (TGFβ)-dependent genes and thereby promote growth and survival. In addition, we identify the KRAB zinc finger protein, ZNF446, and its associated tripartite motif protein, TRIM27, as obligate components of the ZNF165-SMAD3 complex that also support tumor cell viability. Importantly, we find that TRIM27 alone is necessary for ZNF165 transcriptional activity and is required for orthotopic tumor growth in vivo. Our findings indicate that aberrant expression of a testis-specific transcription factor is sufficient to co-opt somatic transcriptional machinery to drive a pro-tumorigenic gene expression program.

Aberrant expression of active leukotriene C4 synthase in CD16+ neutrophils from patients with chronic myeloid leukemia

Blood ◽  
2000 ◽  
Vol 95 (4) ◽  
pp. 1456-1464 ◽  
Author(s):  
Mikael Sjölinder ◽  
Leif Stenke ◽  
Barbro Näsman-Glaser ◽  
Susanne Widell ◽  
Johanne Doucet ◽  
...  
Keyword(s):  
Chronic Myeloid Leukemia ◽  
Messenger Rna ◽  
Myeloid Leukemia ◽  
Interleukin 4 ◽  
Ionophore A23187 ◽  
Healthy Individuals ◽  
Rt Pcr ◽  
Aberrant Expression ◽  
Regular Feature

Elevated leukotriene (LT)C4 synthase activity was observed in peripheral blood granulocyte suspensions from patients with chronic myeloid leukemia (CML). Magnetic cell sorting (MACS) with CD16 monoclonal antibodies (mAbs), which were used to fractionate granulocytes from CML patients and healthy individuals, yielded highly purified suspensions of CD16+ neutrophils. The purity of these cell fractions was verified by extensive morphologic examination. Reverse transcriptase–polymerase chain reaction (RT-PCR) analyses, demonstrating the absence of interleukin-4 messenger RNA (IL-4 mRNA), further confirmed the negligible contamination of eosinophils in these fractions. Notably, purified CML CD16+ neutrophils from all tested patients transformed exogenous LTA4 to LTC4. These cells also produced LTC4 after activation with ionophore A23187 or the chemotactic peptide fMet-LeuPhe (N-formylmethionyl-leucyl-phenylalanine). Subcellular fractionation revealed that the enzyme activity was exclusively distributed to the microsomal fraction. Expression of LTC4 synthase mRNA in CML CD16+neutrophils was confirmed by RT-PCR. Furthermore, Western blot analyses consistently demonstrated expression of LTC4 synthase at the protein level in CML CD16+ neutrophils, whereas expression of microsomal glutathione S-transferase 2 occurred occasionally. Expectedly, LTC4 synthase activity or expression of the protein could not be demonstrated in CD16+ neutrophil suspensions from any of the healthy individuals. Instead, these cells, as well as CML CD16+neutrophils, transformed LTA4 to LTB4. The results indicate that aberrant expression of LTC4 synthase is a regular feature of morphologically mature CML CD16+neutrophils. This abnormality, possibly associated with malignant transformation, can lead to increased LTC4 synthesis in vivo. Such overproduction may be of pathophysiological relevance because LTC4 has been demonstrated to stimulate proliferation of human bone marrow–derived myeloid progenitor cells.

Sign in / Sign up

Export Citation Format

Share Document