Lymphoblastoid cell line with B1 cell characteristics established from a chronic lymphocytic leukemia clone by in vitro EBV infection

Abstract

Chronic lymphocytic leukemia (CLL) cells express the receptor for Epstein-Barr virus (EBV) and can be infected in vitro. Infected cells do not express the growth-promoting set of EBV-encoded genes and therefore they do not yield LCLs, in most experiments. With exceptional clones, lines were obtained however. We describe a new line, HG3, established by in vitro EBV-infection from an IGHV1–2 unmutated CLL patient clone. All cells expressed EBNA-2 and LMP-1, the EBV-encoded genes pivotal for transformation. The karyotype, FISH cytogenetics and SNP-array profile of the line and the patient's ex vivo clone showed biallelic 13q14 deletions with genomic loss of DLEU7, miR15a/miR16–1, the two micro-RNAs that are deleted in 50% of CLL cases. Further features of CLL cells were: expression of CD5/CD20/CD27/CD43 and release of IgM natural antibodies reacting with oxLDL-like epitopes on apoptotic cells (cf. stereotyped subset-1). Comparison with two LCLs established from normal B cells showed 32 genes expressed at higher levels (> 2-fold). Among these were LHX2 and LILRA. These genes may play a role in the development of the disease. LHX2 expression was shown in self-renewing multipotent hematopoietic stem cells, and LILRA4 codes for a receptor for bone marrow stromal cell antigen-2 that contributes to B cell development. Twenty-four genes were expressed at lower levels, among these PARD3 that is essential for asymmetric cell division. These genes may contribute to establish precursors of CLL clones by regulation of cellular phenotype in the hematopoietic compartment. Expression of CD5/CD20/CD27/CD43 and spontaneous production of natural antibodies may identify the CLL cell as a self-renewing B1 lymphocyte.

CK2 and PI3K are direct molecular targets of quercetin in chronic lymphocytic leukaemia

“…Here, we identified in protein kinase CK2 the primary and direct target of quercetin in HG3 cells, derived from a CLL clone immortalized by EBV infection [45]. This cell line was obtained from a patient with IGVH-UM phenotype and biallelic 13q14 deletions with genomic loss of DLEU7, miR15a/miR16–1, resembling the poor prognostic CLL patients.…”

Characterization of a New Chronic Lymphocytic Leukemia Cell Line for Mechanistic In Vitro and In Vivo Studies Relevant to Disease

“…Attempts to expand the number of available CLL lines have been reported. CLL cells may be maintained in culture following EBV transformation using cell feeder layers or other B-cell activation stimuli; however, over time in culture these cells may exhibit diminished CD5 expression [20,21]. However these difficulties may be overcome by developing hetero-hybridoma cell lines to create stable in vitro cultures from CLL patient samples [22].…”

miR-886-3p upregulation in clear cell renal cell carcinoma regulates cell migration, proliferation and apoptosis by targeting PITX1

“…Different from the mechanism of small interfering RNA (siRNA), mature miRNAs usually inhibit genes expression at the post-transcriptional level by binding to the 3'-untranslated regions (3'-UTRs) of target mRNAs, leading to mRNA degradation or depressing translation (8). As miRNA plays important roles in the biological activities of living cells, increasing studies have discovered that certain aberrantly expressed miRNAs in various human cancers were involved in the oncogenesis, progression and metastasis (9). Considerable miRNAs have been characterized as oncogenes or tumor suppressors by targeting downstream genes (10)(11)(12)(13).…”