Molecular study of the perforin gene in familial hematological malignancies

Perforin gene (PRF1) mutations have been identified in some patients diagnosed with the familial form of hemophagocytic lymphohistiocytosis (HLH) and in patients with lymphoma. The aim of the present study was to determine whether patients with a familial aggregation of hematological malignancies harbor germline perforin gene mutations. For this purpose, 81 unrelated families from Tunisia and France with aggregated hematological malignancies were investigated. The variants detected in the PRF1 coding region amounted to 3.7% (3/81). Two of the three variants identified were previously described: the p.Ala91Val pathogenic mutation and the p.Asn252Ser polymorphism. A new p.Ala 211Val missense substitution was identified in two related Tunisian patients. In order to assess the pathogenicity of this new variation, bioinformatic tools were used to predict its effects on the perforin protein structure and at the mRNA level. The segregation of the mutant allele was studied in the family of interest and a control population was screened. The fact that this variant was not found to occur in 200 control chromosomes suggests that it may be pathogenic. However, overexpression of mutated PRF1 in rat basophilic leukemia cells did not affect the lytic function of perforin differently from the wild type protein

Chronic-phase chronic myeloid leukemia: Incidence of BCR/ABL transcript and its correlation with presenting features, response to treatment, and survival

Introduction: Chronic myeloid leukemia (CML) is characterized by Philadelphia chromosome resulting in the fusion between the BCR gene, located on chromosome 22, and the ABL gene on chromosome 9. The prognostic significance of BCR-ABL transcript variants in CML is controversial. The aim of the current study was to evaluate the clinico-hematological presentation and evolution of the disease, response to treatment and survival according to transcript type in chronic phase CML patients. Results: The median age of our population was 50 years with a slight female predominance (sex-ratio 0.78). Sixty percent had the b3a2 transcript and 34% had the b2a2 type. Patients with the co-expression of these two transcripts (4.5%) and those with e19a2 were excluded from the analysis. Patients with b3a2 subtype were associated significantly with thrombocytosis (p = 0.006) and higher Sokal score (p = 0.038) compared to those with b2a2 transcript. The two isolated transcripts were not significantly associated with gender, age group, blast cell percentage or the identified ranges of spleen size. Complete cytogenetic response at 12 months for b3a2 patients and b2a2 patients was 78.6% and 21.4% respectively. This difference was statistically significant (p = 0.001, HR = 9.5, 95% CI 6.5–13.7). Patients with b3a2 transcript had a higher rate of optimal molecular response at 3 months (p = 0.04, HR = 4.2, 95% CI 1–17.3) and major molecular response at 12 months (p = 0.004, HR = 4.9, 95%CI 1.5–15.1). At the date of last follow-up, most patients achieving deep molecular response (MR4 or deeper) belonged to b3a2 group (79%) (p = 0.003, HR = 5.2, 95% CI 1.6–16.4). We did not find a significant difference in OS and EFS between the two groups. Conclusion: Our study concluded that b2a2 transcript is a prognostic factor in cytogenetic and molecular response but further studies are needed to complete this aspect

Granulocytic sarcoma of the rectum: Report of one case that presented with rectal bleeding

Granulocytic sarcoma is an uncommon and localized extramedullary tumor composed of immature granulocytic cells. It may present in association with acute myeloid leukaemia, myelodysplastic syndrome and chronic myelogenous leukaemia. Granulocytic sarcoma may occur in any anatomical site but involvement of the gastrointestinal tract is rare, especially in the rectum. We report on the case of a 17 year old female who presented with rectal bleeding, abdominal pain and weight loss one mo prior to admission. Rectosigmoidoscopy revealed a rectal polypoid and ulcerated mass. The histological examination of the mass showed granulocytic sarcoma. Bone marrow examination was compatible with acute promyelocytic leukaemia (FAB type M3). This case report is a reminder of this peculiar sign of tumoral syndrome in acute myeloid leukaemia. We also discuss diagnostic methods and analyze the disease course