A retrospective study on the clinicopathological and molecular features of 22 cases of natural killer/T-cell lymphoma in children and adolescents.

Natural killer/T-cell lymphoma (NKTCL) in children and adolescents is a rare type of T/NK cell neoplasms. The aim of the present study was to analyze the clinicopathological and genetic features of this rare entity of lymphoma. We evaluated the clinical, histopathological and molecular features of 22 young people with NKTCL, including 15 males and 7 females, with a median age of 15 years. The results revealed that the nasal site was the most involved region while non-nasal sites were observed in 27.3% out of all cases. The tumor cells were composed of small­sized to large cells and 19 (86.4%) cases exhibited coagulative necrosis. The neoplastic cells in all patients were positive for CD3 and the cytotoxic markers. Nineteen (86.4%) cases were positive for CD56. Reduced expression of CD5 was observed in all available cases. CD30 was heterogeneously expressed in 15 (75.0%) cases. All 22 patients were EBV positive. Seven (36.8%) out of all the 19 patients during the follow-up died of the disease, and the median follow­up period was 44 months. Moreover, patients treated with radiotherapy/chemotherapy showed significantly inferior OS compared with the untreated patients. High mutation frequencies were detected including KMT2C (5/5), MST1 (5/5), HLA-A (3/5) and BCL11A (3/5), which involved in modifications, tumor suppression and immune surveillance. These results suggest that NKTCL in children and adolescents exhibits histopathological and immunohistochemical features similar to the cases in adults. Active treatment is necessary after the diagnosis of NKTCL is confirmed. Furthermore, genetic analyse may provide a deep understanding of this rare disease.

Blocking OLFM4/HIF-1α axis alleviates hypoxia-induced invasion, epithelial-mesenchymal transition, and chemotherapy resistance in non-small-cell lung cancer.

Hypoxia is a common biological hallmark of solid cancers, which has been proposed to be associated with oncogenesis and chemotherapy resistance. The purpose of the present study was to investigate the role and underlying mechanisms of olfactomedin 4 (OLFM4) in the hypoxia-induced invasion, epithelial-mesenchymal transition (EMT), and chemotherapy resistance of non-small-cell lung cancer (NSCLC). We observed dramatically upregulated expression of OLFM4 in several NSCLC cell lines, and this effect was more pronounced in A549 and H1299 cells. In addition, our data revealed that OLFM4 expression was remarkably increased in both A549 and H1299 cells under hypoxic microenvironment, accompanied by enhanced levels of hypoxia-inducible factor (HIF)-1α protein. The HIF-1α level was elevated in response to hypoxia, resulting in the regulation of OLFM4. Interestingly, OLFM4 was a positive regulator of hypoxia-driven HIF-1α production. Moreover, depletion of OLFM4 modulated multiple EMT-associated proteins, as evidenced by the enhanced E-cadherin levels along with the diminished expression of N-cadherin and vimentin in response to hypoxia, and thus blocked invasion ability of A549 and H1299 cells following exposure to hypoxia. Furthermore, ablation of OLFM4 accelerated the sensitivity of A549 cells to cisplatin under hypoxic conditions, implying that OLFM4 serves as a key regulator in chemotherapeutic resistance under hypoxia. In conclusion, OLFM4/HIF-1α axis might be a potential therapeutic strategy for NSCLC.

Clinicopathological analysis of the hydroa vacciniforme-like lymphoproliferative disorder with natural killer cell phenotype compared with cutaneous natural killer T-cell lymphoma.

Hydroa vacciniforme-like lymphoproliferative disorder (HVLPD) is defined as a distinctive clinicopathological type of cutaneous lymphoma and a subset of patients with this disease exhibit the natural killer (NK)-cell phenotype. The HVLPD-NK cell phenotype may be difficult to distinguish from cutaneous natural killer T-cell lymphoma (CNKTL), as these two diseases share similar immunophenotypic markers. Therefore, the aim of the present study was to analyze the clinicopathological features of this rare disease and compare these features with those of CNKTL. The clinical, histopathological and molecular features of 5 patients with the HVLPD-NK cell phenotype and 11 patients with CNKTL were evaluated. As well as certain subtle histopathological differences, there marked differences the age, distribution of lesions and clinical course differed between patients with these two diseases. These results suggest that the HVLPD-NK cell phenotype should be classified as a separate disorder and treated accordingly.

Prognostic significance of CD30 expression in nasal natural killer/T-cell lymphoma.

The present study aimed to investigate the expression of tumor necrosis factor receptor superfamily member 8 (CD30) in extranodal natural killer/T-cell lymphoma (ENKTL) using immunohistochemistry, and to evaluate the association between CD30 and clinicopathological and prognostic significance. CD30 expression was detected using immunohistochemistry on paraffin-embedded sections obtained from 122 patients with ENKTL prior to treatment. In total, 70 of these patients with complete clinical data were collected for prognostic analysis. The level of CD30 expression, of the 122 patients with ENKTL, was grouped on the basis of a 5-tiered scale as follows: 0%, no staining; 1+, <25% positive cells; 2+, 25-50% positive cells; 3+, 50-75% positive cells; and 4+, >75% positive cells). In total, 36 (29.5%) were classified as 0; 46 (37.7%) as 1+; 22 (18.0%) as 2+; 12 (9.8%) as 3+; and 6 (4.9%) as 4+. Among the 86 patients with scores between 1+ and 4+, the membranous staining patterns of CD30 expression were sporadic (33.7%), focal (43.2%), diffuse (15.1%) and angiocentric (8.1%). When considering a score of ≥3+ as CD30 positivity (CD30+), the CD30+ group had significantly shorter overall survival rates (P=0.0023) and progression-free survival rate (P=0.0008) compared with CD30 negative group. However, no statistically significant association was found between CD30 expression and clinicopathological features (P<0.05). The present study found that the expression of CD30 (≥3+) was significantly associated with poor prognosis but was not associated with clinical and histopathological parameters in ENKTL. Therefore, CD30 may be a useful prognostic marker in ENKTL.

Inhibitor of DNA binding 4 functions as a tumor suppressor and is targetable by 5-aza-2'-deoxycytosine with potential therapeutic significance in Burkitt's lymphoma.

Epigenetic gene silencing due to promoter methylation is observed in human neoplasia, including lymphoma and certain cancer types. One important target for gene methylation analysis in non-Hodgkin lymphoma (NHL) is inhibitor of DNA binding 4 (ID4). The present study aimed to investigate the gene methylation status of ID4, the expression of ID4 protein and the effect of demethylating agent 5-aza-2'-deoxycytosine (CdR) in the Raji human Burkitt's lymphoma cell line in vitro. Following assessment of the inhibition of Raji cell growth by various concentrations of CdR, the effects of CdR on the expression of ID4 protein were assessed using the immunocytochemical streptavidin-peroxidase method and semi-quantitative analysis, while apoptosis and cell cycle were determined by flow cytometry. The ID4 gene methylation status of Raji cells was tested using methylation-specific polymerase chain reaction analysis. ID4 was methylated and its protein expression was low in the control group, while ID4 was partly or completely demethylated and its protein expression was upregulated in Raji cells treated with CdR. In addition, CdR induced apoptosis and cell cycle arrest in Raji cells in a dose- and time-dependent manner. These results demonstrated that ID4 is hypermethylated and its protein expression is low in Burkitt's lymphoma cells, while CdR reversed the abnormal DNA methylation and induced re-expression of ID4 protein. Hypermethylation of ID4 promotes the proliferation of Burkitt's lymphoma cells; ID4 may function as a tumor suppressor and can be targeted with demethylating compounds such as CdR for the treatment of Burkitt's lymphoma.

KRAS-related noncoding RNAs in pancreatic ductal adenocarcinoma.

Pancreatic ductal adenocarcinoma (PDAC) is a lethal disease with a poor overall prognosis. However, curative resection during the early stages of the disease can greatly improve survival rates, highlighting the importance of early screening and detection. Studies of noncoding RNAs, primarily microRNAs (miRNAs) and long noncoding RNAs (lncRNAs), provide important insights into strategies for the early detection of KRAS-driven PDAC. Here, we summarize our studies and review current reports on research investigating KRAS-related miRNAs and lncRNAs, emphasizing their aberrant expression, mechanisms, carcinogenic effects, and prognostic and predictive capacities in PDAC.

Primary natural killer/T cell lymphoma of the cervix: case report and clinicopathological analysis.

OBJECTIVE: To present pathological and molecular characterizations of a rare case that was diagnosed as nasal-type natural killer (NK)/T cell lymphoma primarily arising in the cervix. CASE REPORT: An Asian woman was admitted to hospital with a hysteromyoma, and laparotomy was performed. A large tumor of the uterus was found, which was limited to the cervix. Pathological examination showed NK/T cell lymphoma, which was supported by histological and immunohistochemical studies and was confirmed by evidence of Epstein-Barr virus infection. Less commonly, this case concerned a cytotoxic T cell phenotype, as molecular studies showed evidence of a clonal T cell receptor γ chain gene rearrangement. Microscopically, prominent and extensive necrosis was the distinctive feature of this case, which reminded us of considering it as a tumor. CONCLUSION: Primary NK/T lymphoma of the cervix is rare. Our experience in this case provided variable information on both pathological and molecular studies. This case may be of value in the differential diagnosis of lymphoid lesions and other small cell tumors of the cervix.

Dickkopf3 overexpression inhibits pancreatic cancer cell growth in vitro.

AIM: To elucidate the role of dickkopf3 (Dkk3) in human pancreatic cancer cell growth. METHODS: Dkk3 mRNA and protein expression in human pancreatic cancer cell lines were detected by real-time reverse transcription polymerase chain reaction (real-time RT-PCR), Western blotting and immunofluorescence. Methylation of the Dkk3 promoter sequence was examined by methylation-specific polymerase chain reaction (MSP) and Dkk3 mRNA expression was determined by real-time RT-PCR after 5-aza-2'-deoxycytidine (5-aza-dC) treatment. The effects of Dkk3 on cancer cell proliferation and in vitro sensitivity to gemcitabine were investigated by CellTiter 96® AQueous One Solution Cell Proliferation Assay (MTS) after transfecting the Dkk3 expression plasmid into human pancreatic cancer cells. The expression of ß-catenin, phosphorylated extracellular signal-regulated protein kinases (pERK) and extracellular signal-regulated protein kinases (ERK) was also examined by real-time RT-PCR and Western blotting after upregulating Dkk3 expression in human pancreatic cancer cells. RESULTS: The results show that the expression levels of both Dkk3 mRNA and protein were low in all pancreatic cancer cell lines tested. The Dkk3 promoter sequence was methylated in the MIA PaCa-2 and AsPC-1 cell lines, which showed reduced Dkk3 expression. These two cell lines, which initially had a methylated Dkk3 promoter, showed increased Dkk3 mRNA expression that was dependent upon the dosage and timing of the DNA demethylating agent, 5-aza-dC, treatment (P < 0.05 or P < 0.01). When Dkk3 expression was upregulated following the transfection of a Dkk3 expression plasmid into MIA PaCa-2 cells, the ability of cells to proliferate decreased (P < 0.01), and the expression of ß-catenin and pERK was downregulated (P < 0.01). Sensitivity to gemcitabine was enhanced in Dkk3 expression plasmid-transfected cells. CONCLUSION: Our findings, for the first time, implicate Dkk3 as a tumor suppressor in human pancreatic cancer, through the downregulation of ß-catenin expression via the ERK-mediated pathway.

[Significance of chemokine receptor CXCR3 expression in breast cancer].

OBJECTIVE: To investigate the expression of CXCR3 and its association with clinicopathologic features in breast carcinoma. METHODS: The expression level of CXCR3 in 18 samples of breast cancer and corresponding normal tissues was investigated using reverse transcriptase-polymerase chain reaction (RT-PCR) and real-time RT-PCR analysis. Immunohistochemistry was carried out to examine the expression of CXCR3 in 80 breast cancers, 20 fibroadenomas and 15 normal breast tissues. RESULTS: (1) RT-PCR and real-time RT-PCR analysis showed a higher level of CXCR3 in breast cancer tissues than that in the corresponding normal breast tissues (P < 0.05). (2) Immunohistochemistry analysis showed that the positive rate of CXCR3 in breast cancer tissues was significantly higher than that in fibroadenomas and the normal breast tissues (P < 0.05). The expression level of CXCR3 in the lymph node-positive group was higher than that in the lymph node-negative group (P < 0.05). The expression of CXCR3 was positively correlated with the number of lymph nodes involved by metastasis, tumor size and pTNM tumor stage (P < 0.05). CONCLUSIONS: Chemokine receptor CXCR3 was up-regulated in breast cancer, and was associated with the progression of breast cancer. CXCR3 might be a novel molecular marker to predict lymph node metastasis and prognosis of breast cancer.

The miR-217 microRNA functions as a potential tumor suppressor in pancreatic ductal adenocarcinoma by targeting KRAS.

Aberrantly expressed microRNA (miRNA) is frequently associated with a variety of cancers, including pancreatic ductal adenocarcinoma (PDAC). In this study, we investigated the expression and possible role of miR-217 in PDAC. Data obtained by locked nucleic acid in situ hybridization and real-time quantitative polymerase chain reaction showed that miR-217 was downregulated in 76.2% (16/21) of PDAC tissues and in all tested PDAC cell lines when compared with the corresponding normal pancreatic tissue. Overexpression of miR-217 in PDAC cells inhibited tumor cell growth and anchorage-independent colony formation and miR-217 decreased tumor cell growth in nude mouse xenografts in vivo. Using in silico predictions, KRAS was defined as a potential direct target of miR-217. Data from the dual-luciferase reporter gene assay showed that KRAS was a direct target of miR-217. Upregulation of miR-217 could decrease KRAS protein levels and reduce the constitutive phosphorylation of downstream AKT. Downregulation of miR-217 expression in PDAC cells could increase cell anchorage-independent colony formation and KRAS protein levels. Furthermore, miR-217 expression was observed to be negatively correlated with KRAS protein expression in PDAC cell lines. We conclude that the frequently downregulated miR-217 can regulate KRAS and function as a tumor suppressor in PDAC. Therefore, miR-217 may serve as a useful therapeutic agent for miRNA-based PDAC therapy.