The impact of circulating 25-hydroxyvitamin D and vitamin D receptor variation on leukemia-lymphoma outcome: Molecular and cytogenetic study

Abstract

Vitamin D (VD) potentially has a crucial function in the development of cancerous cells. This study aims to detect the role of vitamin D concentration and its receptor polymorphisms as possible prognostic biomarkers in patients with leukemia/lymphoma and further will attempt to detect the presence of the Philadelphia chromosome abnormality in chronic myeloid leukemia (CML). Seventy-five patients, in addition to 50 healthy individuals were included. Three single nucleotide polymorphisms of the vitamin D receptor (FokI, Tru91, and ApaI) were identified via Polymerase Chain Reaction- Fragment Length Polymorphism (PCR-RFLP). Sanger sequencing and karyotyping for all patients has been undertaken. Out of 75 patients, 69 (92.0%) were vitamin D deficient. The homozygous genotype TT of FokI is the most commonly found in non-Hodgkin's lymphoma, while the heterozygous CT is observed markedly in CML, chronic lymphoid leukemia, and Hodgkin's lymphoma. The AC and CC genotypes of ApaI are more frequent in patients with CML, while the AC genotype is the most common in HL. In Tru9I, the GG genotype has a wider distribution in individuals diagnosed with leukemia. The PCR-RFLP and Sanger sequencing techniques together confirmed significant genotype respectively. The Philadelphia chromosome, t (9;22) was found in five (17%) cases with CML. There is a marked relationship between FokI, ApaI, and Tru91 polymorphisms and the chance of developing leukemia. In lymphoma, a significant connection between the polymorphisms of FokI and ApaI is frequently detected. Cytogenetic and molecular testing are essential for detection of CML and monitoring therapy response.

Keywords: Karyotyping; Leukemia; Lymphoma; PCR-RFLP; Vitamin D receptor.

Fig. 1

Representative case of an abnormal karyotype of chronic myeloid leukemia patients with t (9; 22).

Fig. 2

Electrophoto of DNA fragments for polymorphism (FokI) after cutting with FokI enzymes. The results of PCR-RFLP showed homozygote C/C being detected as per the bands at 265 bp, while homozygote T/T was apparent from the bands at 96 bp and 169 bp. Heterozygote C/T was detected with a gene size of 265 bp, 96 bp, and 169 bp. Note that the 96 bp bands ran off the gel.

Fig. 3

Electrophoto of DNA fragments for polymorphism (ApaI) after cutting with ApaI restriction enzymes. The results of PCR-RFLP showed that Homozygote A/A was detected as per the bands at 740 bp. While homozygote C/C was apparent from the bands at 530 bp and 210 bp. Heterozygote A/C was detected with gene sizes of 740 bp, 530 bp, and 210 bp.

Fig. 4

Electrophoto of DNA fragments for polymorphism (Tru9I) after cutting with MesI enzymes. The results of PCR-RFLP showed that Homozygote G/G was detected as per the bands at 331 bp. Homozygote A/A was apparent from the bands at 178 bp and 153 bp. Heterozygote G/A was detected with gene sizes of 331 bp, 178 bp, and 153 bp.

Fig. 5

The DNA sequencing for the Fok1 polymorphism (CC-CT-TT) in upper part; Tru91 polymorphism (GG-GA-AA in middle part while the lower part showing Apa1 polymorphism (CC-AC-AA).