Vitamin D Receptor (VDR) Polymorphisms in Pediatric Patients Presenting With Hodgkin's Lymphoma

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

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.

Association between common variants in vitamin D receptor gene and susceptibility to Non-Hodgkin's lymphoma: a case-control study

Vitamin D (VDR)-mediated signaling contributes to the cell signaling pathways that affect cancer development. This study is conducted on 104 patients diagnosed with non-Hodgkin's lymphoma (NHL) and 246 healthy subjects to investigate the link between five genetic variants spanning the VDR gene and the risk of this malignancy in Iranian subjects. The PCR-RFLP method was used for the analysis of BsmI (rs1544410), ApaI (rs7975232), FokI (rs2228570) and TaqI (rs731236) variants. A simple Tetra-ARMS-PCR technique was employed for the genotyping of the Cdx2 (rs11568820) variant. No significant link was found between both groups regarding ApaI (rs7975232) and FokI (rs2228570) variants (P > 0.05). Also, different genetic models of TaqI (rs731236), BsmI (rs1544410) and Cdx2 (rs11568820) polymorphisms were significantly correlated to decreased risk of NHL (Odd ratios <1). We found three haplotypes were strongly associated with an increased risk of NHL (P < 0.0001). Linkage-disequilibrium (LD) analysis showed a strong linkage between TaqI (rs731236) and BsmI (rs1544410) among NHL case and control subjects. Our findings indicated that functional variants of the VDR gene are linked to a decreased risk of NHL in our population. Further replication studies in different ethnic groups are needed to validate our results.

Association of vitamin D receptor gene polymorphisms with osteosarcoma risk and prognosis

OBJECTIVE

Through its receptor (VDR), vitamin D3 plays an important role in a wide variety of cellular processes. Polymorphisms in VDR gene have been linked to risk of various cancers and their prognoses. We conducted a case-control study to analyze he relationship of VDR gene polymorphisms with the occurrence and prognosis of osteosarcoma.

METHODS

Fifty-eight osteosarcoma patients and 75 healthy controls were included in the study. Single nucleotide change polymorphisms (SNPs) in Cdx2, FokI, BsmI, ApaI and TaqI regions of VDR gene were examined with SNaPshot mini-sequencing technique. Allele and genotype frequencies in patients and controls were compared. The association of polymorphic genotypes with osteosarcoma was evaluated. The relationship of the presence of polymorphism to prognostic parameters and survival rates were also analyzed.

RESULTS

Allele and genotype frequencies of Cdx2, FokI, BsmI, ApaI and TaqI regions in VDR gene were found to be similar in patients and controls. Polymorphisms in these regions were not associated with osteosarcoma risk. In patients having Cdx2 polymorphic allele, tumor volume was greater (p:0.041), metastasis was more common (p:0.042) and histopathological response to chemotherapy was worse (p:0.044). Good histopathological response was significantly higher in patients with BsmI homozygous polymorphism (p:0.037). In the presence of heterozygous Cdx2 and homozygous a higher three-year overall survival rate was found, while there was a higher event-free survival rate in patients with ApaI polymorphisms.

CONCLUSION

Our results suggested that although polymorphisms of VDR gene are not related to the development of osteosarcoma, they may be important for prognosis. Understanding the effect of VDR polymorphisms on osteosarcoma will be important in identifying new prognostic parameters and new targets for treatment.

Vitamin D and its receptor polymorphisms: New possible prognostic biomarkers in leukemias

Several factors such as chromosomal translocations, gene mutations, and polymorphisms are involved in the pathogenesis of leukemia/lymphoma. Recently, the role of vitamin D (VD) and vitamin D receptor (VDR) polymorphisms in hematologic malignancies has been considered. In this review, we examine the possible role of VD levels, as well as VDR polymorphisms as prognostic biomarkers in leukemia/lymphoma. Relevant English language literature were searched and retrieved from Google Scholar search engine (1985-2017). The following keywords were used: vitamin D, vitamin D receptor, leukemia, lymphoma, and polymorphism. Increased serum levels of VD in patients with leukemia are associated with a better prognosis. However, low VD levels are associated with a poor prognosis, and VDR polymorphisms in various leukemias can have prognostic value. VD biomarker can be regarded as a potential prognostic factor for a number of leukemias, including acute myeloblastic leukemia (AML), chronic lymphoblastic leukemia (CLL), and diffuse large B-cell lymphoma (DLBCL). There is a significant relationship between different polymorphisms of VDR (including Taq I and Fok I) with several leukemia types such as ALL and AML, which may have prognostic value.