Tumor lysis and acute renal failure in Burkitt's lymphoma: A review on pathophysiology and management

Knockdown of long non‑coding RNA ANRIL inhibits the proliferation and promotes the apoptosis of Burkitt lymphoma cells through the TGF‑β1 signaling pathway

Burkitt lymphoma (BL) has a high mortality rate and its treatment is currently limited to chemotherapy combined with immunotherapy. The long non-coding RNA antisense non-coding RNA in the INK4 locus (ANRIL) has been identified as an oncogene that can regulate cell proliferation and apoptosis in multiple types of cancer. However, the function of ANRIL in BL remains unknown. The present study aimed to determine the effect of ANRIL on cell proliferation and apoptosis in BL. Reverse transcription-quantitative PCR was used to analyze the expression levels of ANRIL in BL cells. The effect of ANRIL knockdown on BL cells was determined using Cell Counting Kit-8, flow cytometric, western blotting, immunofluorescence staining and Hoechst staining assays. The results revealed that ANRIL silencing inhibited the proliferation and promoted the apoptosis of BL cells. In addition, the expression levels of cyclin D1, E2F transcription factor 1 and Bcl-2 were downregulated, while the expression levels of cyclin-dependent kinase inhibitor 1A, Bcl-2-associated X protein, cleaved-caspase-9/pro-caspase-9 and cleaved-caspase-3/pro-caspase-3 were upregulated. Furthermore, the knockdown of ANRIL activated the TGF-β1 signaling pathway, as evidenced by the upregulated expression levels of TGF-β1, phosphorylated (p)-SMAD2/3/SMAD2/3, p-SMAD1/SMAD1 and sphingosine-1-phosphate receptor 2. Moreover, the protective effect of ANRIL silencing in BL could be inhibited by the TGF-β receptor type I/II dual inhibitor, LY2109761. In conclusion, the findings of the present study suggested that the knockdown of ANRIL may inhibit cell proliferation and promote cell apoptosis in BL by regulating the TGF-β1 signaling pathway, which may provide a novel target for the treatment of BL.

Renal Infiltration as a Primary Presentation of Burkitt Lymphoma Secondary to Systemic Lupus Erythematosus: A Rarity Unto a Rarity

Burkitt lymphoma (BL) is a highly aggressive non-Hodgkin B-cell lymphoma characterized by the translocation and deregulation of the MYC (MyeloCytomatosis) gene on chromosome 8. Three distinct clinical forms of BL are recognized: endemic (African), sporadic (non-endemic), and immunodeficiency-associated. Bilateral renal infiltration leading to acute kidney injury (AKI) is a rare initial presentation of BL. Diagnosis is usually made after evaluating the histology and immunophenotyping of the affected tissue.

We report a case of a 46-year-old male who presented with symptoms of AKI resulting from infiltrative disease, a primary presentation of lymphoma. The patient was a known case of systemic lupus erythematosus (SLE) for the last five years and was referred to the nephrology department due to acute elevation in creatinine, from 0.8 mg/dL to 3.57 mg/dL. On physical examination, there was no lymphadenopathy. Nephrology and SLE workup revealed low complement protein levels and absolute neutrophils, lymphocytes, and metamyelocytes. Renal ultrasound (USG) showed both kidneys with symmetric and edematous appearance. Biopsy affirmed high-grade B-cell lymphoma, positive for BCL-6 (B-cell leukemia/lymphoma) and CD-10 (cell surface marker) and negative for BCL-2 (B-cell leukemia/lymphoma). PET (positron emission tomography) scan showed extensive hypermetabolic lymphadenopathy in multiple areas. The patient was started on chemotherapy and on continuous renal replacement therapy. He improved clinically, and his creatinine lowered down to 0.8 mg/dL. Repeat USG showed decreased edematous appearance of both kidneys.

Primary renal infiltration by BL is a rare presentation in adults. Prompt renal biopsy will change the course of treatment and can affect the prognosis. It is thoroughly advised to keep this malignancy in mind when making a diagnosis for AKI.

Adult Burkitt lymphoma- an Island between lymphomas and leukemias

Background: Burkitt lymphoma is a rare, aggressive and rapidly fatal, B-cell non-Hodgkin’s lymphoma. It has an incidence of 0.4/100,000 age-adjusted to the USA standard population. Here we describe the case of a 77-year-old patient who presented with Burkitt lymphoma.

Case: A 77-year-old male presented to his primary care physician with fatigue and listlessness and was referred to the hospital with a white blood cell count (WBC)-23.7 K/uL (neutrophils 37%, lymphocyte 11%, blasts 9%) and platelets-19 K/uL. During his stay in the hospital, repeat investigations revealed WBC-29.9 K/uL (neutrophils 22%, lymphocyte 27%, atypical lymphocytes 5%, blasts 20%) and platelets-10 K/uL with no evidence of mucosal bleeds, neck or abdominal masses or generalized lymphadenopathy. Bone marrow aspirate revealed the presence of MYC rearrangements (8q24) on flow cytometry and fluorescent in-situ hybridization (FISH), indicative but not typical of BL. He was transfused with platelets due to a rapidly deteriorating platelet count and episodes of epistaxis. He was discharged after four days with a plan of outpatient chemotherapy over a period of 4 months. An Ommaya reservoir was placed in the right ventricle for intrathecal chemotherapy. After four months of chemotherapy, computerized tomography of the chest, abdomen, and pelvis confirmed remission. A magnetic resonance imaging of the brain a month after completion of chemotherapy revealed metastatic lymphoma in the temporal, parietal and occipital lobes. He was discharged to hospice for palliative care.

Conclusion: Unconventional presentations, as seen in our case of a leukemia-like picture in the absence of a bulky disease, are the quagmire that might delay aggressive management and result in poorer outcomes.

Pattern of childhood cancer in University College Hospital, Ibadan during 1991-2010 and comparison with the previous three decades

BACKGROUND

Cancer is an important cause of morbidity and mortality worldwide in children under 15 years of age, with the incidence and mortality rate varying from 40 to 155 per million children.

AIM

To describe the pattern of childhood cancer in Ibadan, Nigeria.

OBJECTIVE

To compare the findings of this study with those of previous studies in Ibadan and internationally.

METHODS

A retrospective review of histologically and cytologically confirmed cases of cancer in children aged <15 years diagnosed at University College Hospital (UCH), Ibadan between January 1991 and December 2010 was undertaken. The cases were categorised using the International Classification of Childhood Cancer, third edition (ICCC-3).

RESULTS

There were 625 cases comprising 360 (57·6%) males with a modal age of 3 years. The most common neoplasms were lymphomas (140, 22·4%), of which 90% were non-Hodgkin lymphomas, with Burkitt lymphoma constituting the majority of cases (73). Other common neoplasms were retinoblastomas (21%), soft tissue sarcomas (14·9%), leukaemias (10·2%) and CNS tumours (6·9%). Lymphomas, bone tumours, malignant hepatic tumours and other malignant epithelial neoplasms had the highest mean and modal ages, while retinoblastomas, neuroblastomas, germ cell tumours and renal tumours had the lowest mean and modal ages. During 1960-72 there were 1326 cases and during 1973-90 there were 1881 cases and the proportion of lymphomas was 58·9% and 45·4%, respectively. The present study demonstrated a marked decline in the number of cases and proportion of lymphomas (22·4%), particularly Burkitt lymphomas.

CONCLUSION

During the last 20 years, there has been a decline in the number of cases of childhood cancer seen at UCH, Ibadan. This may be due to the establishment of additional specialist centres in the sub-region. Owing to a persistent decline in the frequency of Burkitt lymphoma, retinoblastoma is now the most common individual childhood cancer seen at Ibadan.

Diagnosis and treatment of rituximab-induced acute tumor lysis syndrome in patients with diffuse large B-cell lymphoma

Acute tumor lysis syndrome (ATLS) is a recognized complication of the treatment of malignant lymphomas and is associated with significant morbidity and mortality. However, there have been few reports of the occurrence of ATLS in patients treated with rituximab. This study reports 2 patients with high-grade diffuse large B-cell non-Hodgkin's lymphoma who presented high tumor load, were sensitive to treatment and had multiple risk factors for ATLS. Both patients developed ATLS after treatment with rituximab and, despite aggressive supportive therapy, died of multiple organ failure. These cases illustrate that ATLS can occur after treatment with rituximab and that a high index of suspicion is necessary for the prompt diagnosis of ATLS.