We also created IKZF1 knockdown B-ALL cell lines with over 50% reduction of Ikaros, mimicking haplosufficient Ikaros deletions, and again performed qPCR to investigate the downstream targets.
We studied Ikaros gene expression in normal human bone marrow, normal thymocytes, normal fetal liver-derived immature lymphocyte precursor cell lines, eight different ALL cell lines, and leukemic cells from 69 children with ALL (T-lineage ALL, n = 18; B-lineage ALL, n = 51).
Moreover, expression of Notch1, an essential gene for developing hematological cells and T-ALL, was found to be negatively correlated with β-arrestin1 in ALL.
We examined the expression of Ikaros isoforms in 11 leukemic cell lines and adult acute lymphoblastic leukemia cells from 36 patients with B-precursor acute lymphoblastic leukemia (pre-B ALL) and nine with T-precursor acute lymphoblastic leukemia (pre-T ALL), using reverse transcriptase-polymerase chain reaction (RT-PCR) analysis.
We analyzed the expression levels of the Ikaros gene family, Ikaros and Aiolos, in human bone marrow samples from patients with adult acute lymphoblastic leukemia [ALL (n = 46; B-cell ALL = 41; T-cell ALL = 5)].
Particular attention will be paid to the data concerning the incidence of p16INK4A (and p15INK4B) gene(s) inactivation in human acute lymphoblastic leukemias.
These data show the coexistence of multiple genetic defects in childhood B-lineage ALL Cell lines with t(12;21) will facilitate the study of TEL-AML1 and AML1-TEL fusion proteins as well as TEL and CDKN2 gene inactivation in leukemia transformation and progression.
Genetic alterations of the transcription factor IKZF1 ("IKAROS") are detected in around 15-30% of cases of <i>BCR-ABL</i>-negative B-cell precursor acute lymphoblastic leukemia.
Patients with ALL who expressed pRb had a higher probability and patients who expressed p16 a lower probability of remaining in first continuous remission, but the results were not statistically significant.
Notably, genetic alteration of the lymphoid transcription factor gene IKZF1 is a hallmark of multiple subtypes of ALL with poor prognosis, including BCR-ABL1-positive lymphoid leukemia and a subset of 'BCR-ABL1-like' ALL cases that, in addition to IKZF1 alteration, harbor genetic mutations resulting in aberrant lymphoid cytokine receptor signaling, including activating mutations of Janus kinases and rearrangement of cytokine receptor-like factor 2 (CRLF2).
To further investigate the molecular mechanisms underlying proliferation suppression and apoptosis and explore effective downstream target genes, we used RNA interference (RNAi) technology to down-regulate the expression of Notch-1 in GSIs-resistant T-ALL cell lines.
Since most hematological malignancies-except ALL-are infrequently associated with p16INK4A and retinoblastoma (Rb) gene alteration it seems worthwhile to explore cdk4 and cdk6 expression to determine whether or not the disruption of the p16INK4A/Rb/cdk4/cdk6 regulatory loop might play a role in their pathogenesis.
We therefore analyzed the clinical and biological implications of this feature by studying p16ink4a expression in 58 cases of childhood ALL. mRNA and protein were significantly correlated and both appeared more highly expressed in B than in T lineage ALLs: 13 out of the 15 T cell ALLs did not show any p16ink4a expression.
IKAROS family zinc finger 1/IKZF1 is a transcription factor important in lymphoid differentiation, and a known tumor suppressor in acute lymphoid leukemia.
Here, we explored the IL7R and SH2B3 expression in adult ALL and found that IL7R is significantly higher and Sh2B3 lower expressed in B-ALL compared to normal bone marrow control, and the IL7RhighSH2B3low is associated with high-risk factors, and with high relapse rate and low disease-free survival rate in the patients.
Importantly, hypermethylation of DLX3 significantly reduces its expression in MLL-AF4 rearranged leukemias while methylation is almost absent in TEL-AML1 positive ALL specimens.