HLA-B gene methylation and expression in Behçet's syndrome: a potential role of epigenetics in the pathogenesis

OBJECTIVES

The HLA-B51 locus has the strongest association with Behçet's syndrome (BS). The presence of a CpG island in the HLA-B gene led us to examine the role of epigenetic regulation in BS.

METHODS

HLA-B51 genotyping was performed via sequence-specific PCR in 15 index familial BS cases, 17 affected relatives, 26 unaffected relatives, 46 sporadic BS cases, and 41 healthy controls. HLA-B methylation level was determined using the Zymo OneStep qMethyl kit, and HLA-B51 mRNA level was assessed by quantitative real-time PCR in 14 index familial BS cases, 15 affected relatives, 15 unaffected relatives, 11 sporadic BS cases, and 10 healthy controls.

RESULTS

HLA-B51 carrier ratio was 13/15 in index familial cases, 13/17 in affected relatives, 22/26 in unaffected relatives, 8/25 in healthy controls, and 35/47 in sporadic BS cases. HLA-B51 expression level in HLA-B51+ BS cases was 2.2-fold higher than in their unaffected relatives (p=0.0149) and 1.3-fold higher than in healthy controls (p=0.0188), while sporadic BS cases had a 2.7-fold higher level than healthy controls (p=0.0487). HLA-B promoter methylation was significantly lower in HLA-B51+ familial BS cases than in unaffected relatives (0.4-fold, p=0.01), affected relatives (0.36-fold, p=0.0219), and healthy controls (0.34-fold, p=0.0371) and slightly lower in HLA-B51+ sporadic BS cases than in healthy controls (0.71-fold, p=0.2347). There was an inverse correlation between HLA-B promoter methylation and HLA-B51 expression in HLA-B51+ sporadic BS cases (p=0.0164).

CONCLUSIONS

This study indicates epigenetic involvement associated with the HLA-B51 locus in BS, both in familial and sporadic cases. Further studies with larger sample sizes are needed to confirm our results.

The prognostic value of serum levels of a proliferation-inducing ligand (APRIL) in treatment-naïve patients with chronic lymphocytic leukemia

Background/aim

A proliferation-inducing ligand (APRIL) has been investigated as a prognostic marker in chronic lymphocytic leukemia (CLL) patients. However, there is no cut-off level for serum APRIL (sAPRIL) levels that predict time to treatment in CLL patients.

Materials and methods

Between May and December 2012, 94 consecutive CLL patients and 25 healthy controls were assessed. sAPRIL levels were measured by ELISA. Demographic data and prognostic markers were obtained from the patients’ files. Treatment-naïve patients were followed up for 6.5 years for any treatment need.

Results

Patients were divided into 3 groups: Treatment-naïve (n = 47), chemotherapy receiving (n = 25), and those who had received chemotherapy previously (n = 22). There was no difference in median sAPRIL levels of patients who were receiving chemotherapy at the sampling time and the healthy controls, which indicates that sAPRIL levels might be influenced by treatment. For treatment-naïve patients, the best cut-off in predicting time to treatment was found at the sAPRIL level of 2.04 ng/mL, with 78% sensitivity and 63% specificity. Time to treatment was significantly earlier in the APRIL high group (n = 27) than in the APRIL low group (n = 20) (P = 0.010, log-rank test).

Conclusion

sAPRIL, a simple, promising blood test which can be measured by ELISA, will likely obtain a place in the wide range of prognostic markers in CLL. Prospective large-scale studies are required to validate and confirm the feasibility of the proposed cut-off level of 2.04 ng/mL as a predictor of time to treatment in treatment-naïve CLL patients.

What is the long term acid inhibitor treatment in gastroesophageal reflux disease? What are the potential problems related to long term acid inhibitor treatment in gastroesophageal reflux disease? How should these cases be followed?

The meta-analyses of observational studies (OBS) showed the risk of any fracture and hip fracture slightly increased with proton pump inhibitor (PPI) treatment depending on the dose and regardless of time. This was not observed with histamine-2 receptor antagonists (H2RA). The risk of bacterial overgrowth and spontaneous bacterial peritonitis were increased with PPI therapy, but not with H2RA. In meta-analyses of OBS, a slight increase was observed in the risk of community-acquired pneumonia (CAP) in the early stages (<1 month) of PPI use and particularly at high doses. In a five-year LOTUS study, no difference was found in vitamin B12, folic acid, vitamin D, and calcium values in terms of the initial and end of follow-up levels. No increase in the risk of premalignant gastric lesions was observed in the meta-analysis of RCTs in which PPI treatment (≥6 months) was given to Helicobacter pylori negative patients. The risk of hypomagnesemia with PPI use was increased in patients having GFR<60, using diuretics, and over 65 years of age. Quasi-experimental studies showed a reduced zinc absorption with PPI use. In the meta-analysis of OBS, long-term (>1 year) PPI use increased the risk of fundic polyps, but no risk was found in shorter use. The meta-analyses of RCTS showed no difference between PPI and surgery or placebo arms and between the arms of H2RA and placebo in terms of all side effects. No difference was found between the PPI and H2RA arms both in all and serious adverse effects.

Bone marrow transplantation for Behçet's disease: a case report and systematic review of the literature

OBJECTIVES

Behçet's disease (BD) can be life threatening and may be refractory to corticosteroids and immunosuppressives. There has been some experience with haematopoietic stem cell transplantation (HSCT) in BD either for severe, refractory disease or for a haematological condition. The objectives of this study were to describe a BD patient undergoing HSCT and to evaluate the outcomes of BD patients who underwent HSCT.

METHODS

We report a BD patient with refractory gastrointestinal (GI) involvement who had HSCT for concomitant myelodysplastic syndrome (MDS). We also performed a systematic literature search regarding HSCT for either refractory disease or concomitant haematological conditions in BD patients.

RESULTS

A 30-year-old woman with refractory GI BD involvement with trisomy 8 MDS underwent a successful myeloablative allogeneic HSCT resulting in complete resolution of both BD and MDS. Additionally we identified 14 manuscripts providing data on 19 patients with BD who had HSCT. Among these 20 patients, including ours, refractory disease was the indication of transplantation in 9, while 11 patients were transplanted because of accompanying haematological conditions. Transplant indications for the nine patients (four male, five female) with refractory BD were neurological involvement in five, pulmonary artery aneurysm in two, GI disease in one and not reported in one patient. Three patients with neurological disease, both patients with pulmonary artery aneurysm and the patient with intestinal involvement achieved complete remission of their disease. Six patients transplanted for haematological conditions, including the presented case, also had GI involvement of BD. All of these patients achieved complete remission of GI findings after HSCT.

CONCLUSION

When considering HSCT, the potential adverse events and complications, which can be fatal, need to be kept in mind.