Tamai Minori, Huang Meixian, Kagami Keiko, Abe Masako, Somazu Shinpei, Shinohara Tamao, Harama Daisuke, Watanabe Atsushi, Akahane Koshi, Goi Kumiko, Sugita Kanji, Goto Hiroaki, Minegishi Masayoshi, Iwamoto Shotaro, Inukai Takeshi
Department of Pediatrics, School of Medicine, University of Yamanashi, Shimokato, Chuo, Yamanashi, 1110, Japan.
Yamanashi Red Cross Blood Center, Kofu, Japan.
Cancer Cell Int. 2020 Sep 4;20(1):434. doi: 10.1186/s12935-020-01524-0.
The genetic variants of the ARID5B gene have recently been reported to be associated with disease susceptibility and treatment outcome in childhood acute lymphoblastic leukemia (ALL). However, few studies have explored the association of ARID5B with sensitivities to chemotherapeutic agents.
We genotyped susceptibility-linked rs7923074 and rs10821936 as well as relapse-linked rs4948488, rs2893881, and rs6479778 of ARDI5B by direct sequencing of polymerase chain reaction (PCR) products in 72 B-cell precursor-ALL (BCP-ALL) cell lines established from Japanese patients. We also quantified their ARID5B expression levels by real-time reverse transcription PCR, and determined their 50% inhibitory concentration (IC50) values by alamarBlue assays in nine representative chemotherapeutic agents used for ALL treatment.
No significant associations were observed in genotypes of the susceptibility-linked single nucleotide polymorphisms (SNPs) and the relapsed-linked SNPs with ARID5B gene expression levels. Of note, IC50 values of vincristine (VCR) (median IC50: 39.6 ng/ml) in 12 cell lines with homozygous genotype of risk allele (C) in the relapse-linked rs4948488 were significantly higher (p = 0.031 in Mann-Whitney U test) than those (1.04 ng/ml) in 60 cell lines with heterozygous or homozygous genotypes of the non-risk allele (T). Furthermore, the IC50 values of mafosfamide [Maf; active metabolite of cyclophosphamide (CY)] and cytarabine (AraC) tended to be associated with the genotype of rs4948488. Similar associations were observed in genotypes of the relapse-linked rs2893881 and rs6479778, but not in those of the susceptibility-linked rs7923074 and rs10821936. In addition, the IC50 values of methotrexate (MTX) were significantly higher (p = 0.023) in 36 cell lines with lower ARID5B gene expression (median IC50: 37.1 ng/ml) than those in the other 36 cell lines with higher expression (16.9 ng/ml).
These observations in 72 BCP-ALL cell lines suggested that the risk allele of the relapse-linked SNPs of ARID5B may be involved in a higher relapse rate because of resistance to chemotherapeutic agents such as VCR, CY, and AraC. In addition, lower ARID5B gene expression may be associated with MTX resistance.
最近有报道称，ARID5B基因的遗传变异与儿童急性淋巴细胞白血病（ALL）的疾病易感性和治疗结果相关。然而，很少有研究探讨ARID5B与化疗药物敏感性之间的关联。
我们通过对72株从日本患者中建立的B细胞前体ALL（BCP-ALL）细胞系的聚合酶链反应（PCR）产物进行直接测序，对ARDI5B的易感性相关rs7923074和rs10821936以及复发相关rs4948488、rs2893881和rs6479778进行基因分型。我们还通过实时逆转录PCR定量其ARID5B表达水平，并通过alamarBlue试验测定其在用于ALL治疗的9种代表性化疗药物中的50%抑制浓度（IC50）值。
在易感性相关单核苷酸多态性（SNP）和复发相关SNP的基因型与ARID5B基因表达水平之间未观察到显著关联。值得注意的是，在复发相关rs4948488中具有风险等位基因（C）纯合基因型的12株细胞系中，长春新碱（VCR）的IC50值（中位IC50：39.6 ng/ml）显著高于（曼-惠特尼U检验中p = 0.031）60株具有非风险等位基因（T）杂合或纯合基因型的细胞系中的IC50值（1.04 ng/ml）。此外，马法兰[Maf；环磷酰胺（CY）的活性代谢产物]和阿糖胞苷（AraC）的IC50值倾向于与rs4948488的基因型相关。在复发相关rs2893881和rs6479778的基因型中也观察到类似关联，但在易感性相关rs7923074和rs10821936的基因型中未观察到。此外，ARID5B基因表达较低的36株细胞系中甲氨蝶呤（MTX）的IC50值显著高于（p = 0.023）其他36株表达较高的细胞系中的IC50值（16.9 ng/ml）。
在72株BCP-ALL细胞系中的这些观察结果表明，ARID5B复发相关SNP的风险等位基因可能由于对VCR、CY和AraC等化疗药物的耐药性而导致较高的复发率。此外，ARID5B基因表达较低可能与MTX耐药性相关。
