Expression of growth-regulated genes in human acute leukemias

We have investigated the expression of six growth-regulated genes (c-myc, c-myb, p53, 4F1, 2F1, and ornithine decarboxylase) and the S-phase-specific histone H3 gene in acute myeloid and lymphoid leukemic cells. We have purposely chosen three growth-regulated protooncogenes that share similar biological features and three gene sequences that have in common the cell cycle dependence of their expression in cells of different tissue and in different species. The level of expression was determined by measuring the amounts of specific RNA by Northern blot analysis. Levels of expression of the six growth-regulated genes were compared to the level of expression of the S-phase-specific H3 gene and among themselves. This method distinguishes the increased expression of a growth-regulated gene due to a true altered activation from over-expression which simply reflects an increase in the fraction of cycling cells. We have found that six of 14 patients with acute leukemias have markedly high ratios of c-myc/H3, c-myc/p53, and c-myc/c-myb expression. Two patients with altered c-myc expression have also a high ratio p53/H3. Within the group of cell cycle-dependent genes the ratios of expression seem in the overall much more regular with the clear exception of a patient with acute myelogenous leukemia in which the ratios 4F1/H3 and 2F1/H3 are significantly increased. A possible interpretation of these findings is that the fraction of noncycling leukemic cells that often constitute the majority of the entire leukemic population is in some cases in a true resting state, whereas in other cases heterogeneous degrees of growth arrest might occur. The altered expression of c-myc seems the feature most commonly associated with this putative growth arrest of leukemic cells suggesting that this gene may contribute to the impairment of proliferative control that is associated with the leukemic phenotype.     

Expression of nuclear envelope lamins A and C in human myeloid leukemias.

The lamins are intermediate filament proteins that form a fibrous layer at the periphery of the nucleus. Experiments in cell-free systems have suggested that mammalian lamins A and C mediate an interaction between chromatin and the inner nuclear membrane that is essential for the reformation of the nucleus after mitosis. Other investigations, however, have suggested that lamins A and C are absent from myeloid cells and myeloid leukemia cell lines. To further investigate this apparent paradox, highly sensitive Western blotting techniques were utilized in the present study to examine the expression of lamins A and C in a series of human myeloid leukemia cell lines and in bone marrow samples from patients with acute nonlymphocytic leukemia (ANLL) and chronic myelogenous leukemia. Western blotting revealed that HL-60 progranulocytic leukemia cells contained an average of 0.1 x 10(6) copies of lamins A and C per cell compared to 0.5 x 10(6) copies of lamin B1 (the quantitatively prominent human B-type lamin) per cell. During the process of phorbol ester-induced maturation to macrophages, the mRNA for lamins A and C increased in abundance, with a concomitant 4-fold increase in the average cellular content of these polypeptides. To rule out the possibility that the low but detectable levels of lamins A and C observed in untreated HL-60 cells reflected incipient maturation, the content of lamins A and C was analyzed in ANLL cell lines that do not mature toward granulocytes or monocytes. Lamins A and C were readily detected in cell lines (KG1a, HEL, Mo-7e) derived from patients with a variety of subtypes of ANLL. Expression of lamins A and C was not limited to myeloid cell lines. These polypeptides were also detectable in marrow samples from 9 of 26 patients with ANLL including at least 1 patient from each of the 5 subtypes of ANLL examined. In contrast, only 1 of 12 marrow samples from patients with aggressive phase chronic myelogenous leukemia and chronic myelogenous leukemia in blast crisis contained readily detectable lamins A and C. The implications of these findings for current hypotheses regarding the functions of the lamin polypeptides are discussed.     

Frequent co-expression of the HOXA9 and MEIS1 homeobox genes in human myeloid leukemias.

There is increasing evidence that HOX homeobox genes play a role in leukemogenesis. Recent studies have demonstrated that enforced co-expression of HOXA9 and MEIS1 in murine marrow leads to rapid development of myeloid leukemia, and that these proteins exhibit cooperative DNA binding. However, it is unclear whether co-activation of HOXA9 and MEIS genes is a common occurrence in human leukemias. We surveyed expression of HOXA9 and MEIS1 in 24 leukemic cell lines and 80 patient samples, using RNase protection analyses and immunohistochemistry. We demonstrate that the expression of HOXA9 and MEIS1 in leukemia cells is uniquely myeloid, and that these genes are commonly co-expressed in myeloid cell lines and in samples of acute myelogenous leukemia (AML) of all subtypes except in promyelocytic leukemia. While HOXA9 is expressed in most cases of chronic myelogenous leukemia, MEIS1 is weakly expressed or not at all. Immunohistochemical staining of selected AML samples showed moderate to high levels of HOXA9 protein, primarily cytoplasmic, in leukemic myeloblasts, with weaker and primarily nuclear staining for MEIS1. These data support the concept that co-activation of HOXA9 and MEIS1 is a common event in AML, and may represent a common pathway of many different oncogenic mutations.     

Expression of Wnt genes in human colon cancers

A polymerase chain reaction-based approach was used to study the expression of Wnt genes in human colon carcinoma tissue and normal colon mucosa. In a number of cases Wnts 2, 4, 5a, 6 and/or 7a were found to be more highly expressed in colon carcinoma tissue compared to surrounding normal-appearing mucosa from the same patients. Wnts 4, 5a, 6 and 7a, but not 2, were also found to be expressed in colon cancer cell lines. The increased levels of expression of these Wnt genes in tumor tissue may indicate their possible involvement in human colon tumorigenesis.     

钙黏蛋白相关基因在慢性粒细胞白血病中的表达及其作用

目的研究钙黏蛋白（Cad）相关基因在慢性粒细胞白血病（CML）不同发展时期患者骨髓单个核细胞（BM-MNC）中的表达,探讨Cad相关基因在CML发展中的作用。方法收集2013年12月至2014年12月长治医学院附属和济医院收治的48例CML患者的骨髓标本,其中慢性期29例,进展期19例。应用实时定量反转录一聚合酶链反应（qRT-PCR）法检测所有患者BM-MNC中上皮型钙黏蛋白（E．Cad）和神经元型钙黏蛋白（N-Cad）基因的相对表达量,并对结果进行分析。结果CML患者BM-MNC中均可检测到E-Cad、N-Cad基因的表达。E-Cad基因在CML进展期患者中的相对表达量低于慢性期患者（0．20±0．35比1．19±0．87,P〈0．01）,而N-Cad基因在进展期患者中的相对表达量高于慢性期患者（0．89±0．45比0．57±0．47,P〈0．05）。E-Cad基因表达与外周血原始细胞比例呈负相关（r=-0．705,P〈0．01）。结论E-Cad、N-Cad基因表达与CML的疾病进展相关,其表达水平可作为评估疾病进展风险的指标之一。     

DEK 的表达与结直肠癌患者预后的相关性研究

目的：采用免疫组化技术,分析DEK基因在结直肠癌患者中的表达情况及其与预后的相关性。方法：运用免疫组化SP法,检测DEK基因在169例结直肠癌患者肿瘤组织及癌旁组织中的表达情况,并运用统计分析软件分析DEK表达水平与结直肠癌患者预后的相关性。结果：DEK的表达率在结直肠癌组织（85／169,50．30％）明显高于癌旁正常组织（28／169,16．57％）,差异具有统计学意义（P〈0．01）。DEK在肿瘤组织中的表达情况与病人年龄、性别、肿瘤分化程度、TNM分期及肿瘤大小等因素无相关性,与总生存率（OS）显著相关（P〈0．05）。结论：DEK表达水平与结直肠癌预后密切相关,DEK高表达的结直肠癌患者预后较差。     

Expression of human myeloid cell nuclear differentiation antigen (MNDA) in acute leukemias

Human myeloid cell nuclear differentiating antigen (MNDA) is a Mr 55,000 non-histone basic nuclear protein expressed in myeloid leukemia cell lines that are at late stages of differentiation (HL-60 and U937) and in normal granulocytes and monocytes, but is not present in lymphoid cells or in other human cells and tissues tested. Affinity purified monospecific polyclonal antibodies and rat monoclonal antibodies have been developed for the immunocytochemical detection of MNDA. Using these antibodies, we surveyed 21 cases of acute leukemia classified by French-American-British (FAB) Group criteria, two cases of biphenotypic acute leukemia and one case of blast crisis of chronic granulocytic leukemia for the presence of MNDA. The most intense staining reactions were present in the nuclei of two cases of acute promyelocytic (FAB M3) leukemia. MNDA was not detected in three of five cases of acute myeloblastic leukemia without maturation (FAB M1). The remaining two cases of the M1 category showed weak to moderate staining. No staining reaction was seen in acute lymphocytic leukemia (ALL), biphenotypic leukemia or the lymphoid blast crisis of chronic granulocytic leukemia. Variable staining reactions were demonstrated in the remaining cases. These data suggest that the presence of MNDA is correlated with myeloid and monocytic differentiation in acute leukemia, being strongly expressed in M3 type, often not detected in M1 leukemia and absent in ALL.     

MAGE-A genes are not expressed in human leukemias.

Immunotherapy is promising to improve the prognosis of human leukemias, at least as adjuvant treatment. Tumor-associated antigens such as antigens encoded by MAGE-A1, -A2, -A3, -A4, -A6 and -A12 genes might provide tools in this field. We demonstrated recently that the presentation peptides encoded by MAGE-A genes might make leukemic blasts suitable targets to cytolytic T lymphocytes. We reported previously negative data of MAGE-A1 gene expression in hematological malignancies, but in further studies positive results of MAGE-A gene expression were published in some subtypes of hematological malignancies such as T leukemia, myeloma and Hodgkin's disease. This led us to enlarge the screening of MAGE-A gene expression in human leukemias. In the RT-PCR screening of a large panel including 154 patients, only weak signal were detected in a few samples. We conclude that MAGE-A genes are not expressed in human leukemias.     

Targeting Ras in myeloid leukemias.

Ras proteins normally relay growth-promoting signals from many activated cell surface receptors, and they are altered by oncogenic point mutations in approximately 30% of human cancers. Activating KRAS and NRAS mutations are especially common in malignancies of the pancreas, lung, and colon, and in myeloid leukemia. Here, we discuss general strategies for targeting hyperactive Ras signaling in cancer cells with specific reference to myeloid malignancies.     

Genetic variations of DNA repair genes and their prognostic significance in patients with acute myeloid leukemia

Common genetic variations in genes involved in DNA repair or response to genotoxic stress may influence both cancer susceptibility and treatment response individually or interactively. However, in acute myeloid leukemia (AML), the relevance of these genetic variations remains to be fully established. In this study, we analyzed 42 genetic variations among 15 candidate genes in 307 AML patients and 560 age‐sex matched controls. Their associations with chemotherapy response were further evaluated in combination with other well‐established prognostic factors. An increased risk of AML was found in individuals heterozygous for XPD 2251A>C (rs13181) with an odds ratio (OR) of 1.637 (95% confidence interval [CI]: 1.118–2.395), and the increased risk could be attributed to C allele (OR = 1.505, 95% CI: 1.061–2.134). Postchemotherapy response analysis revealed that AML patients heterozygous for ATM 4138C>T (rs3092856) or GG homozygous for TP53 215C>G (rs1042522) were independently linked to inferior treatment outcomes. These results uncover novel prognostic factors for AML patients treated with chemotherapy and may also indicate an etiological role of XPD in this disease.     

锌转运蛋白ZIP在肝细胞癌中的表达及其预后意义

目的:通过深入挖掘肿瘤公共数据库中的基因信息,分析ZIP转运蛋白家族成员在肝细胞癌(hepa-tocellular carcinoma,HCC)中的表达情况及与临床预后的相关性.方法:通过Oncomine和UCSC Xena等肿瘤学公共数据库对ZIP转运蛋白在HCC中的表达情况进行分析;使用cBioPortal数据库探...     

Clinicopathologic and prognostic significance of matrilysin expression at the invasive front in human colorectal cancers

Matrix metalloproteinases (MMPs) have been implicated in tumor progression. Matrilysin, one of the matrix metalloproteinases, is frequently overexpressed in gastrointestinal cancers. The aim of our study was to assess the validity of matrilysin as a prognostic marker of colorectal cancers. Matrilysin expression was immunohistochemically analyzed using formalin-fixed, paraffin-embedded specimens from 113 colorectal cancer patients who had undergone curative surgery. The lumenal surface of neoplastic glands in the superficial layer was apically stained, while the cytoplasm of cancer cells at the invasive front was diffusely stained for matrilysin. Sections with immunostaining signals in more than 30% of carcinoma cells at the invasive front, which were observed in 47 (42%) cases, were judged as being positive for matrilysin. Matrilysin positivity was significantly correlated with the depth of invasion, lymph node metastasis, lymphatic invasion, advanced Dukes' stage and poor outcome. Patients with matrilysin-positive cancer had a significantly shorter overall survival time than those with matrilysin-negative cancer. For patients with intermediate invasive tumor (T2 or T3), only matrilysin was a significant prognostic variable for predicting overall survival in multivariate analysis. Matrilysin expression at the invasive front could be an important marker, predicting an unfavorable prognosis after surgical treatment in patients with colorectal cancer.     

VEGF and myeloid leukemias

Vascular endothelial growth factor and vascular endothelial growth factor receptors participate in the growth and survival of myeloid leukemic progenitors. With the development of multiple anti-angiogenic agents, there is potential that some of these novel agents will have anti-leukemic activity. Since these agents work by mechanisms distinct from current cytotoxic chemotherapies, they may be useful both in chemoresistant leukemia patients and in combinations to improve remission rates and remission durations.     

Biological and prognostic significance of chromosome 5q deletions in myeloid malignancies.

The presence of del(5q), either as the sole karyotypic abnormality or as part of a more complex karyotype, has distinct clinical implications for myelodysplastic syndromes (MDS) and acute myeloid leukemia. The 5q- syndrome, a subtype of low-risk MDS, is characterized by an isolated 5q deletion and <5% blasts in the bone marrow and can serve as a useful model for studying the role of 5q deletions in the pathogenesis and prognosis of myeloid malignancies. Recent clinical results with lenalidomide, an oral immunomodulatory drug, have shown durable erythroid responses, including transfusion independence and complete cytogenetic remissions in patients with del(5q) MDS with or without additional chromosomal abnormalities. These results indicate that lenalidomide can overcome the pathogenic effect of 5q deletion in MDS and restore bone marrow balance. The data provide important new insights into the pathobiology of 5q chromosomal deletions in myeloid malignancies.     

Expression of the myeloperoxidase gene in acute and chronic myeloid leukemias: relationship to the expression of cell cycle-related genes

The expression of the myeloperoxidase (MPO) gene was studied, by means of Northern blot analysis in 14 cases of acute myeloid leukemia (AML), 11 cases of chronic myeloid leukemia (CML), and 6 cases of CML blast crisis, and in HL60 cells before and after induction of terminal differentiation with retinoic acid (RA), phorbol esters (TPA), or vitamin D. The expression of a panel of cell cycle-related genes, namely C-MYC, histone H3, ornithine decarboxylase, P53, vimentin, and calcyclin, was also studied in the same cell populations. Our results indicate that: (a) MPO gene expression (steady state mRNA levels) is strictly confined to the first stages of myeloid differentiation, reaching its peak at the promyelocyte stage and becoming undetectable in mature granulocytes and monocytes; (b) cells devoid of any detectable MPO enzymatic activity such as leukemic basophils have a high content of MPO mRNA; and (c) MPO gene expression is not related to the growth activity of the cell population. Finally, our results show that the pattern of expression of growth-regulated genes in the neoplastic myeloid disorders AML, CML, and CML blast crisis is remarkably different.