MicroRNA-543 inhibits the proliferation, migration, invasion, and epithelial-mesenchymal transition of triple-negative breast cancer cells via down-regulation of ACTL6A gene

PurposeTo investigate the effect of microRNA-543 (miR-543) on the proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT) of triple-negative breast cancer (TNBC) cells, and the associated mechanism.MethodsHuman breast cancer cells (MDA-MB-231, HCC1937, and MCF-7, ZR-75–1) and normal human breast epithelial cell line (MCF10A) were transfected with miR-543 mimics or inhibitor using lipofectamine 2000. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) and Western blotting were used to determine the mRNA and protein expression levels of miR-543, actin-like protein 6A (ACTL6A), vimentin, Snail, and E-cadherin in breast cancer cells/tissue. Cell counting kit-8 (CCK-8), wound-healing, and Transwell assays were used to measure the effect of miR-543 on TNBC cell proliferation, invasion, and migration. Overall survival was determined using data from Gene Expression Omnibus (GEO) and Cancer Genome Atlas (TCGA) databases. Bioinformatics analysis and luciferase reporter gene assay were used to determine the regulatory effect of miR-543 on ACTL6A.ResultsThe level of expression of miR-543 was significantly lower in breast cancer cells/tissue than in normal human breast epithelial cell/tissue (p < 0.05). MicroRNA-543 expression level was significantly reduced in TNBC cells/tissue, relative to the other breast cancer cells/normal breast tissue (p < 0.05). MicroRNA-543 significantly suppressed tumor growth and the proliferation, migration, invasion, and epithelial–mesenchymal transition (EMT) of TNBC cells, in mouse xenograft model (p < 0.05).

MicroRNA-543 inhibits the proliferation, migration, invasion, and epithelial-mesenchymal transition of triple-negative breast cancer cells via down-regulation of ACTL6A gene.

PURPOSE: To investigate the effect of microRNA-543 (miR-543) on the proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT) of triple-negative breast cancer (TNBC) cells, and the associated mechanism. METHODS: Human breast cancer cells (MDA-MB-231, HCC1937, and MCF-7, ZR-75-1) and normal human breast epithelial cell line (MCF10A) were transfected with miR-543 mimics or inhibitor using lipofectamine 2000. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) and Western blotting were used to determine the mRNA and protein expression levels of miR-543, actin-like protein 6A (ACTL6A), vimentin, Snail, and E-cadherin in breast cancer cells/tissue. Cell counting kit-8 (CCK-8), wound-healing, and Transwell assays were used to measure the effect of miR-543 on TNBC cell proliferation, invasion, and migration. Overall survival was determined using data from Gene Expression Omnibus (GEO) and Cancer Genome Atlas (TCGA) databases. Bioinformatics analysis and luciferase reporter gene assay were used to determine the regulatory effect of miR-543 on ACTL6A. RESULTS: The level of expression of miR-543 was significantly lower in breast cancer cells/tissue than in normal human breast epithelial cell/tissue (p < 0.05). MicroRNA-543 expression level was significantly reduced in TNBC cells/tissue, relative to the other breast cancer cells/normal breast tissue (p < 0.05). MicroRNA-543 significantly suppressed tumor growth and the proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT) of TNBC cells, in mouse xenograft model (p < 0.05). CONCLUSIONS: miR-543 influences the biological behavior of TNBC cells by directly targeting ACTL6A gene. miR-543 could serve as a novel diagnostic and therapeutic target for TNBC.

Effects of azithromycin in bronchiolitis obliterans syndrome after hematopoietic SCT--a randomized double-blinded placebo-controlled study.

Bronchiolitis obliterans syndrome (BOS) is an important complication after hematopoietic SCT (HSCT). Recent observations suggested that azithromycin might improve lung function in BOS after HSCT. We conducted a randomized double-blinded placebo-controlled study on azithromycin in patients with BOS after HSCT. The treatment group (n=10) received oral azithromycin 250 mg daily while the control group (n=12) received placebo daily for 12 weeks. Respiratory symptoms were assessed by the St George Respiratory Questionnaires and spirometry at baseline (drug commencement), 1, 2, 3 (drug cessation) and 4 months (1 month after drug cessation). There was no significant difference in the baseline demographic characteristics between the treatment and the control groups in age, gender, time from HSCT to BOS, time since diagnosis of BOS, chronic GVHD, baseline respiratory symptom scores and baseline forced expiratory volume in 1 s (FEV(1)). Throughout and after 3 months of treatment, there were no significant changes in respiratory symptom scores and FEV(1) measurements between the treatment and the control groups. In conclusion, there was no significant benefit of 3 months of oral azithromycin on the respiratory symptoms and lung function in patients with relatively late BOS after HSCT in this randomized placebo-controlled study.

Hepatitis C in haematological patients.

There is no consensus guideline concerning the management of chronic hepatitis C patients during chemotherapy, and immunosuppression. However, there are some suggestions in literature that hepatitis C viral load increases during chemotherapy and there is a risk of rebound immunity against hepatitis C after discontinuation of immunosuppression with a consequent liver injury. A close monitoring of liver function of these patients is prudent during treatment of haematological malignancy. Antiviral treatment is deferred after the completion of chemotherapy and recovery of patients' immunity to minimize the toxicity of treatment. A combination of pegylated interferon and ribavirin is the standard therapy in hepatitis C infected haematological patients.

An update in management of noncutaneous T-cell lymphomas.

T-cell lymphoma is a heterogeneous group of diseases. Except for ALK positive anaplastic large cell lymphoma, T-cell lymphoma responds to conventional chemotherapy unfavourably, and most patients carry poor prognosis. In recent years, efforts have been made to improve the outcome of T-cell lymphoma patients. Novel agents, high-dose therapy, and allogeneic stem cell transplantation are studied, and various results are reported in literature. This paper looks into the prognostication and treatment approach of different entities of noncutaneous T-cell lymphoma and would focus on the latest updates in its management.

A case of mixed adult Wilms' tumour and angiosarcoma responsive to carboplatin, etoposide and vincristine (CEO).

Here we report an unusual case of mixed Wilms' tumour and angiosarcoma in a 38-year-old female patient who presented with haematuria and right lower back pain. A computed tomographic (CT) scan confirmed a massive renal tumour associated with extensive retroperitoneal lymph node involvement, bony metastases and a right hip fracture. She was initially managed with palliative nephrectomy, which was followed by rapid postoperative deterioration. Histopathology revealed differentiated adult Wilms' tumour with renal angiosarcoma, whereas the pathology of the para-aortic lymph node and bone metastasis revealed angiosarcoma only. In view of her cachexia and cytopaenia, emergency chemotherapy was initiated using a modified regimen of carboplatin, etoposide and vincristine (CEO) in preference to the more traditional but less well-tolerated VAC (vincristine, actinomycin D, cyclophosphamide). Four cycles of this protocol yielded a dramatic response on re-staging CT scan. This case suggests that highly angiogenic tumours such as angiosarcoma may be effectively palliated using agents usually reserved for refractory Wilms' tumour, and supports the view that adult Wilms' tumour is more sensitive to such agents.

Liver graft-versus-host disease after donor lymphocyte infusion for relapses of hematologic malignancies post allogeneic hematopoietic stem cell transplantation.

Graft-versus-host disease (GVHD) is the commonest complication after donor lymphocyte infusion (DLI). In 19 patients undergoing DLI for relapses of hematologic malignancies post hematopoietic stem cell transplantation (HSCT), 11 developed GVHD, of whom nine had isolated liver involvement, and two had liver and skin involvement. The clinical diagnosis of liver GVHD was hepatitic in six patients (55%) and classical in five patients (45%). Patients with GVHD post-DLI showed a different clinical pattern when compared to a cohort of 106 cases of GVHD post-HSCT, in having significantly more isolated liver involvement (9/11 vs 17/106, P<0.001), and less skin (2/11 vs 80/106, P<0.001) and gut (0/11 vs 28/106, P<0.001) involvement. However, liver GVHD post-DLI and post-HSCT had comparable patient characteristics, underlying diseases, clinical subtypes (classical and hepatitic) and response to treatment.

Hodgkin's lymphoma in Chinese migrants to British Columbia: a 25-year survey.

BACKGROUND: Compared with the West, Hodgkin's lymphoma in Oriental countries is characterized by a lower incidence rate and a higher proportion of mixed cellularity histology. Both environmental and genetic factors may be involved. PATIENTS AND METHODS: The incidence and pattern of pathology of Hodgkin's lymphoma in the migrant Chinese population (0.4 million) in British Columbia (population 3.2 million) were studied. From a computerized database, all Hodgkin's lymphoma cases diagnosed in British Columbia from 1970 to 1997 were identified. Chinese descent was determined using patient surname by standard methodology and verified from the treatment record or by patient interview. The corresponding figures from the Chinese population in Hong Kong were used for comparison. For incidence rates, the age-specific incidence of Hodgkin's lymphoma in Hong Kong was obtained from the government cancer registry. For comparison of histology subtypes, 200 Hodgkin's lymphoma records from a Hong Kong regional referral center for the same time period were reviewed. Crude and age-standardized incidence rates were calculated by 5-year intervals in terms of age and calendar year, and relative rates were compared between the three populations. RESULTS: From 1970 to 1997, Hodgkin's lymphoma was diagnosed in 34 Chinese patients in BC, with 24 cases diagnosed from 1970 to 1994. Thus, the crude and age-adjusted incidence rates from 1970 to 1994 were 0.91 and 1.14 per 100,000 per year in the British Columbia Chinese migrant population. Within the same period, 1862 cases of Hodgkin's lymphoma were diagnosed in British Columbia, giving a provincial background crude and age-adjusted incidence rates of 5.2 and 4.87 per 100,000 per year. The number of cases in the Hong Kong Chinese population (1970-1994) was 404, giving crude and age-adjusted incidence rates of 0.32 and 0.31 per 100,000 per year, respectively. Corrected for age and calendar year trends, the observed 25-year incidence of Hodgkin's lymphoma in British Columbia Chinese was significantly lower than expected from the British Columbia background population [24 observed versus 71 expected cases; standardized incidence ratio (SIR) = 0.34; 90% confidence interval (CI) 0.24-0.48; P <0.0001]. On the other hand, it is higher than that expected by extrapolating from the Hong Kong Chinese population (24 observed versus 8.5 expected cases; SIR = 2.81; 90% CI 1.94-3.95; P <0.0001). The difference is mainly accounted for by young patients with nodular sclerosis type disease in the migrant population. CONCLUSIONS: Although any conclusion about the impact of migration on Hodgkin's lymphoma incidence and types in the Chinese population must be considered tentative due to the small number of observed cases and confounding variables such as age, changing diagnostic standards and secular trends in Hodgkin's lymphoma rates, our data demonstrate a tendency for the Chinese population of British Columbia to take on a Western pattern of Hodgkin's lymphoma. This observation provides additional evidence that both genetic and environmental influences play a role in the pathogenesis of this lymphoma, and that environmental factors can exert their influence over a relatively short period of time.

Can defects in transferrin receptor 2 and hereditary hemochromatosis genes account for iron overload in HbH disease?

Iron overload was found to be the major cause of disability in Chinese HbH disease patients although they were not on regular blood transfusion. The transferrin receptor 2 (TFR2) and hereditary hemochromatosis (HFE) genes were examined to see if inheritance of these gene defects may be a possible cause of iron overload in 45 HbH patients. A novel intronic (IVS6 (+6) T-->A) mutation of the TFR2 gene was identified in one patient, and six others were found to carry a known missense mutation (exon 5, I238M) that was also present in one normal control subject. One HbH patient and one normal control carried the H63D mutation of the HFE gene. Since only eight out of 45 iron-overloaded HbH patients carry a defect in the TFR2 or HFE gene in the heterozygote state and their iron loading status was comparable to the matched controls without such defects, it would appear that the accumulation of excess iron in HbH disease is more likely a result of increase dietary absorption secondary to ineffective erythropoiesis.

Quantification of polyoma BK viruria in hemorrhagic cystitis complicating bone marrow transplantation.

Polyoma BK virus (BKV) is frequently identified in the urine of bone marrow transplantation (BMT) patients with hemorrhagic cystitis (HC). However, viruria is common even in asymptomatic patients, making a direct causative role of BKV difficult to establish. This study prospectively quantified BK viruria and viremia in 50 BMT patients to define the quantitative relationship of BKV reactivation with HC. Adenovirus (ADV) was similarly quantified as a control. More than 800 patient samples were quantified for BKV VP1 gene with a real-time quantitative polymerase chain reaction. Twenty patients (40%) developed HC, 6 with gross hematuria (HC grade 2 or higher) and 14 with microscopic hematuria (HC grade 1). When compared with asymptomatic patients, patients with HC had significantly higher peak BK viruria (6 x 10(12) versus 5.7 x 10(7) genome copies/d, P <.001) and larger total amounts of BKV excreted during BMT (4.9 x 10(13) versus 7.7 x 10(8) genome copies, P <.001). There was no detectable increase in BK viremia. Binary logistic regression analysis showed that BK viruria was the only risk factor, with HC not related to age, conditioning regimen, type of BMT, and graft-versus-host disease. Furthermore, the levels of ADV viruria in patients with or without HC were similar and comparable with those of BK viruria in patients without HC, suggesting that the significant increase in BK viruria in HC patients was not due to background viral reactivation or damage to the urothelium. BK viruria was quantitatively related to the occurrence of HC after BMT.

Successful mismatched sibling cord blood transplant in Hb Bart's disease.

A 20-month-old girl with Hb Bart's disease, who had survived neonatal complications, underwent HLA-DR antigen mismatched sibling cord blood transplantation successfully. Immune thrombocytopenia, which occurred around 2.5 months after transplant, responded to intravenous gamma-globulin. The fetal hemoglobin level rose to a peak of 52.3% on day +69 post transplant and declined gradually during the following year. Ten percent of hemoglobin Bart's was detected 2 months after transplant and this reflects the alpha-thalassemia trait of the donor.

BCL10 somatic mutations rarely occur in gastric lymphoma: detection of high frequency of polymorphisms in BCL10 coding region.

The BCL10 gene, recently isolated due to its involvement in the t(1;14)(p22;q32) of mucosa-associated lymphoid tissue B cell non-Hodgkin lymphoma (MALToma), was shown to have frequent somatic mutations and short deletions within the coding region in MALToma and a variety of other lymphomas and solid tumors. These observations have been recently questioned. In this study, we examined BCL10 gene mutations by direct sequencing of the entire coding region of the BCL10 gene, amplified from paired normal and tumor genomic DNAs, as well as tumor cDNAs, in 23 cases of primary gastric B cell non-Hodgkin lymphomas, comprising of 6 cases of MALToma and 17 cases of diffuse large cell (DLC) lymphoma. Heterozygosity due to three types of known polymorphisms in codon 5 (17.3%), codon 8 (21.7%), and codon 213 (8.6%) were observed in both normal germline DNA and tumor DNAs and tumor cDNAs in individual cases. In one case (4.3%) G/C heterozygosity in codon 8 in normal germline DNA was reduced to homozygosity (LOH) in tumor DNA and cDNA. Mutations inactivating BCL10 gene product function were not found in any of these cases. Moreover, post-transcriptional alterations were not indicated by abnormalities in BCL10 mRNA sequence in tumor cDNAs in these gastric lymphoma cases. Our results show that somatic mutations in the BCL10 gene rarely occur in gastric lymphoma and indicate that this gene is unlikely to be of pathogenetic significance in the majority of gastric lymphomas.

Expression of HLA class I, beta(2)-microglobulin, TAP1 and IL-10 in Epstein-Barr virus-associated nasal NK/T-cell lymphoma: Implications for tumor immune escape mechanism.

Several mechanisms of immune escape might be in operation in Epstein-Barr virus (EBV)-associated nasal NK/T-cell lymphoma. We have previously shown the downregulation of the immunogenic EBV nuclear antigens by alternative promoter usage and the preferential selection of the deletion genotype of latent membrane protein 1 in nasal lymphoma. To understand further the strategies used for immune escape by this tumor, we examined by immunohistochemistry HLA class I expression in 15 cases using frozen sections, along with beta(2)-microglobulin and transporter associated with antigen processing 1 (TAP1) expression in 39 cases using paraffin sections. All nasal NK/T-cell lymphomas showed positive staining for HLA class I, beta(2)-microglobulin and TAP1 on most tumor cells, except for two cases (5%) in which most of the tumor cells lacked beta(2)-microglobulin staining. We next immunostained for interleukin-10 on frozen sections in 13 cases, all of which showed strong expression by most tumor cells. Transcription of human interleukin-10 but not EBV BCRF1 (viral interleukin-10) was identified by reverse transcriptase-polymerase chain reaction in these nasal NK/T-cell lymphomas. Overall, our data suggest that global downregulation of HLA class I or TAP1 rarely accounts for the ability of nasal NK/T-cell lymphoma to evade immunosurveillance and that other immune escape mechanisms may be operating in nasal NK/T-cell lymphoma, such as production of interleukin-10 to suppress the local immune response.

Identification and characterization of BCL6 translocation partner genes in primary gastric high-grade B-cell lymphoma: heat shock protein 89 alpha is a novel fusion partner gene of BCL6.

Primary gastric high-grade B-cell lymphoma (HGBL) is a special type of non-Hodgkin's lymphoma. So far, the genetic features of this tumor have not been well characterized. Recently, a high incidence of BCL6 rearrangements has been detected in HGBL. However, no previous cytogenetic studies have found translocations involving the BCL6 locus (3q27) in HGBL, and the genetic basis underlying the BCL6 rearrangements in this tumor remains unclear. We therefore characterized the partner genes of BCL6 in five primary gastric HGBLs with a rearranged BCL6 gene by analyzing BCL6 transcripts using the 5' RACE (rapid amplification of cDNA end) strategy. BCL6 translocation partner genes were identified at the 5' end of the chimeric transcripts in all five cases, including the immunoglobulin heavy-chain (IGH) gene in three cases and the immunoglobulin lambda-light-chain gene and the heat shock protein 89 alpha (HSP89A) gene in the other two cases. The chimeric transcripts in all cases contained the intact BCL6 exon 2, but lacked exon 1, which was replaced by sequences from the partner genes, suggesting that BCL6 expression was under the control of regulatory sequences of the partner genes. These results, for the first time, indicate that immunoglobulin genes, especially IGH, are the most common BCL6 translocation partner genes in primary gastric HGBL and that HSP89A is a novel partner of BCL6. Because immunoglobulin genes are also the most frequent partners of BCL6 in nodal diffuse large B-cell lymphoma (DLBCL), these data suggest that primary gastric HGBL shares a common genetic basis with nodal DLBCL. Genes Chromosomes Cancer 27:69-75, 2000.