Ochratoxin A-enhanced glycolysis induces inflammatory responses in human gastric epithelium cells through mTOR/HIF-1α signaling pathway.

Ochratoxin A (OTA) is a mycotoxin commonly found in several food commodities worldwide with potential nephrotoxic, hepatotoxic and carcinogenic effects. We previously showed for the first time that OTA treatment enhanced glycolysis in human gastric epithelium (GES-1) cells in vitro. Here, we found that OTA exposure activated inflammatory responses, evidenced by increasing of NF-κB signaling pathway-related protein (p-p65 and p-IκBα) expressions and elevating of inflammatory cytokine (IL-1ß and IL-6) mRNA expressions in GES-1 cells. To elucidate the role of glycolysis in inflammatory effects triggered by OTA, we pretreated GES-1 cells with glycolysis inhibitor (2-deoxy-D-glucose, 2-DG) before OTA exposure. The result showed that 2-DG reduced the protein expressions of p-p65 and p-IκBα and alleviated the mRNA expressions of inflammatory cytokines in OTA-treated GES-1 cells. Furthermore, OTA activated the mTOR/HIF-1α pathway by increasing the protein expressions of p-mTOR, p-eIF4E and HIF-1α, and inhibition of mTOR with rapamycin or silencing HIF-1α with siRNA significantly attenuated OTA-enhanced glycolysis by reducing glycolysis related genes and thereby decreasing inflammatory effects of GES-1 cells. These results demonstrate that OTA activates inflammatory responses in GES-1 cells and this is controlled by mTOR/HIF-1α pathway-mediated glycolysis enhancement. Our findings provide a novel mechanistic view into OTA-induced gastric cytotoxicity.

The Clinical Significance and Prognostic Role of Whole-Blood Epstein-Barr Virus DNA in Lymphoma-Associated Hemophagocytic Lymphohistiocytosis.

PURPOSE: To evaluate the role of circulating Epstein-Barr virus (EBV) DNA in lymphoma-associated hemophagocytic lymphohistiocytosis (HLH). METHODS: We conducted a retrospective cohort study to explore the clinical and prognostic significance of EBV DNA in lymphoma-associated HLH. We included adult patients with combined diagnoses of lymphoma and HLH from January 2010 and November 2022 by retrieving the medical record system. RESULTS: A total of 281 patients with lymphoma-associated HLH were identified. Elevated whole-blood EBV DNA was observed in 54.4% (153/281) of patients, and the median copy number was significantly higher in the T/NK-cell malignancies (199,500, interquartile range, 30,000-1,390,000) than that in the B-cell non-Hodgkin lymphoma (5520, interquartile range, 1240-28,400, P < 0.001). The optimum cutoff for predicting survival was 16,100 copies/mL. Compared to the patients with EBV DNA ≤ 16,100 copies/mL, those with EBV DNA > 16,100 copies/mL were younger and had more T/NK-cell malignancies, lower levels of neutrophils and fibrinogen, and higher levels of hemoglobin, alanine aminotransferase, aspartate aminotransferase, lactic dehydrogenase, and ß2-microglobulin. A higher load of EBV DNA (> 16,100 copies/mL), thrombocytopenia (< 100 × 109/L), neutropenia (< 1 × 109/L), hypofibrinogenemia (≤ 1.5 g/L), and elevated levels of creatinine (> 133 µmol/L) were independent adverse predictors of 60-day overall survival and overall survival. A prognostic index based on EBV DNA and the other four factors was established to categorize the patients into four groups with significantly different outcomes. CONCLUSION: Our study identified high EBV load as a risk factor for lymphoma-associated HLH and established a prognostic index to predict outcomes.

HDAC6-G3BP2 promotes lysosomal-TSC2 and suppresses mTORC1 under ETV4 targeting-induced low-lactate stress in non-small cell lung cancer.

TSC-mTORC1 inhibition-mediated translational reprogramming is a major adaptation mechanism upon many stresses, such as low-oxygen, -ATP, and -amino acids. But how cancer cells hijack the adaptive pathway to survive under low-lactate stress when targeting glycolysis-related signaling remains uncertain. ETV4 is an oncogenic transcription factor frequently dysregulated in human cancer. We previously found that ETV4 is associated with tumor progression and poor prognosis in non-small cell lung cancer (NSCLC). In this study, we report that ETV4 controls HK1 expression and glycolysis-lactate production to activate mTORC1 by relieving TSC2 repression of Rheb in NSCLC cells. Targeting ETV4-induced low-lactate stress is an important input for TSC2 to inhibit mTORC1 and global protein synthesis, while the core stress granule components G3BP2 and HDAC6 are selectively translated. Mechanistically, G3BP2 recruits lysosomal-TSC2 to suppress mTORC1. HDAC6 deacetylates TSC2 to sustain protein stability and associates with G3BP2 to facilitate more recruiting of TSC2 to inactivate mTORC1. In addition, the microtubule retrograde transport activity of HDAC6 drives the aggregate-like perinuclear-mTOR distribution paralleled by lower mTORC1 activity under stress. Thus, HDAC6-G3BP2 is the key complex that promotes lysosomal-TSC2 and suppresses mTORC1 when targeting ETV4, which might represent a critical adaptive mechanism for cell survival under low-lactate challenges.

Limb expression 1-like protein promotes epithelial-mesenchymal transition and epidermal growth factor receptor-tyrosine kinase inhibitor resistance via nucleolin-mediated ribosomal RNA synthesis in non-small cell lung cancer.

Limb expression 1-like protein (LIX1L) might be an RNA-binding protein involved in post-transcriptional regulation. However, little is known regarding the biological function and mechanism of LIX1L in cancer cells. Here we demonstrate a clear correlation between LIX1L expression and epithelial-mesenchymal transition (EMT) markers in 81 non-small cell lung cancer (NSCLC) tissues and The Cancer Genome Atlas database, suggesting that LIX1L is a mesenchymal marker. Besides, LIX1L expression is obviously elevated in TGFß1-induced EMT NSCLC cells and enhances cell migration, invasion, anoikis resistance, epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI) resistance, and proliferation. Interestingly, the increased LIX1L expression prominently localizes to the nucleoli, where it physically interacts with the key ribosome biogenesis regulator NCL protein, inducing ribosomal RNA (rRNA) synthesis in EMT NSCLC cells. NCL knockdown or inhibition of rRNA synthesis reverses the enhanced EMT functions and proliferation ability caused by LIX1L overexpression in NSCLC cells, indicating that NCL expression and rRNA synthesis participates in LIX1L-mediated biological functions during EMT. Collectively, our findings suggest that the LIX1L-NCL-rRNA synthesis axis is a novel EMT-activated mechanism. Targeting the pathway might be a therapeutic option for EMT and EGFR-TKI resistance in NSCLC.

TNF-α-dependent lung inflammation upregulates PD-L1 in monocyte-derived macrophages to contribute to lung tumorigenesis.

Chronic inflammation, which is dominated by macrophage-involved inflammatory responses, is an instigator of cancer initiation. Macrophages are the most abundant immune cells in healthy lungs, and associated with lung tumor development and promotion. PD-L1 is a negative molecule in macrophages and correlated with an immunosuppressive function in tumor environment. Macrophages expressing PD-L1, rather than tumor cells, exhibits a critical role in tumor growth and progression. However, whether and how PD-L1 in macrophages contributes to inflammation-induced lung tumorigenesis requires further elucidation. Here, we found that higher expression of PD-L1 in CD11b+ CD206+ macrophages was positively correlated with tumor progression and PD-1+ CD8+ T cells population in human adenocarcinoma patients. In the urethane-induced inflammation-driven lung adenocarcinoma (IDLA) mouse model, the infiltration of circulating CD11bhigh F4/80+ monocyte-derived macrophages (MoMs) was increased in pro-tumor inflamed lung tissues and lung adenocarcinoma. PD-L1 was mainly upregulated in MoMs associated with enhanced T cells exhaustion in lung tissues. Anti-PD-L1 treatment can reduce T cells exhaustion at pro-tumor inflammatory stage, and then inhibit tumorigenesis in IDLA. The pro-tumor lung inflammation depended on TNF-α to upregulate PD-L1 and CSN6 expression in MoMs, and induced cytokines production by alveolar type-II cells (AT-II). Furthermore, inflammatory AT-II cells could secret TNF-α to upregulate PD-L1 expression in bone-marrow driven macrophages (BM-M0). Inhibition of CSN6 decreased PD-L1 expression in TNF-α-activated macrophage in vitro, suggesting a critical role of CSN6 in PD-L1 upregulation. Thus, pro-tumor inflammation can depend on TNF-α to upregulate PD-L1 in recruited MoMs, which may be essential for lung tumorigenesis.

Spectrum and trigger identification of hemophagocytic lymphohistiocytosis in adults: A single-center analysis of 555 cases.

Limited data are available about the underlying causes of hemophagocytic lymphohistiocytosis (HLH) in adults. We collected and analyzed the data of 555 cases of adult HLH. HLH in 242 patients were malignancies-related and lymphoid malignancies (42.0%, 233/555) were the most common causes. Aggressive natural killer-cell leukemia, diffuse large B-cell lymphoma, and extranodal natural killer/T-cell lymphoma, nasal type were the most common specified pathological subtypes. Epstein-Barr virus (EBV) (69.0%, 100/145) was the most common pathogen among the cases of infections-related HLH (26.1%, 145/555). Malignancies-related HLH showed male preponderance, more common splenomegaly, more severe anemia and thrombocytopenia, and significantly elevated soluble CD25. In patients with abnormal lymphoid cells in the bone marrow (BM) and increased EBV DNA copy number, 48.9% (45/92) of them were aggressive natural killer-cell leukemia. In patients with abnormal lymphoid cells in the BM and normal EBV DNA copy number, 66.2% (47/71) of them were B-cell non-Hodgkin lymphoma. In patients with elevated EBV DNA copy number but no abnormal lymphoid cells in the BM, 71.0% (98/138) of these cases were EBV infection. In conclusion, lymphoid malignancy is the most common underlying cause of adult HLH, followed by EBV infection. Based on the BM morphology and EBV load, we developed a diagnostic flow for rapid determination of the triggers for HLH.

Association of marital status with stage and survival in patients with mycosis fungoides: A population-based study.

BACKGROUND: Previous studies have shown that marital status was associated with stages and survival in patients with melanoma or Merkel cell carcinoma. To date, the impacts of marital status on stage and survival in patients with mycosis fungoides (MF) have not been determined yet. METHODS: A total of 3375 eligible cases diagnosed from 2004 to 2015 were included from the Surveillance, Epidemiology, and End Results (SEER) database. Association of marital status with stage and survival in patients with MF was analyzed. RESULTS: Married patients were more likely to be diagnosed at T1 stage (p = 0.041). And married patients were less likely to present with lymph node involvement (p = 0.007). More favorable overall survival (p < 0.001) and cancer-specific survival (p < 0.001) were demonstrated in married patients as compared with divorced patients or widowed patients. A clinically feasible prognostic model including marital status, age, sex, race, and stage at presentation was constructed. CONCLUSION: Married marital status was associated with earlier stage at diagnosis and longer survival compared with divorced or widowed marital status in patients with MF.

Survival trends for extranodal NK/T-cell lymphoma, nasal type from different anatomical sites: a population-based study.

BACKGROUND: Extranodal natural killer/T-cell lymphoma (NKTCL), nasal type mostly involves the upper aerodigestive tract (UAT). NKTCLs derived from the UAT are referred to as nasal NKTCLs, while those without UAT involvement are referred to as extra-nasal NKTCLs. In this study, we aimed to investigate the outcomes and survival trends of NKTCLs from different anatomical sites. METHODS: Data from the US Surveillance, Epidemiology, and End Results (SEER) database on NKTCL (diagnosed between 1987 and 2016) were retrospectively analyzed. RESULTS: A total of 714 patients with NKTCL were included. The median overall survival (OS) and cancer-specific survival (CSS) were 36 and 57 months, respectively. For the entire cohort, the OS was improved from era 1 to era 2 with marginal significance (P=0.0595), however, no improvement was shown in CSS. For nasal NKTCLs, the OS of patients from era 2 was significantly improved compared to that of patients from era 1 (P=0.0244). The OS was significantly improved in non-cavity nasal NKTCLs (P=0.031) but not in nasal cavity NKTCLs (P=0.2982). Significant improvements in OS (P=0.0025) and CSS (P=0.0176) were found in stage I/II non-cavity nasal NKTCLs. For patients with extra-nasal NKTCLs, no difference was found in survival outcomes between the 2 eras. CONCLUSIONS: We have demonstrated that the outcomes of non-cavity nasal NKTCLs, especially those in stage I/II, have improved in the new era, while the outcomes of nasal cavity NKTCLs and extra-nasal NKTCLs have not improved. Our study highlights the heterogeneity in clinical outcomes and biology among NKTCLs from different sites. More studies are warranted to define the optimal treatments for patients with NKTCLs.

Long non-coding RNA LINC01137 contributes to oral squamous cell carcinoma development and is negatively regulated by miR-22-3p.

PURPOSE: Long noncoding RNAs (lncRNAs) are emerging as key regulators in cancer initiation and progression. LINC01137 is a recently identified lncRNA of which the functional role in the development of oral squamous cell carcinoma (OSCC) has not been determined yet. METHODS: We analyzed the expression of LINC01137 using a microarray-based OSCC gene expression dataset (GSE31056), and validated the results obtained using RT-qPCR in 26 pairs of primary OSCC tumor tissues and adjacent non-tumor tissues. The proliferative and invasive effects of LINC01137 on OSCC cells were determined using CCK-8, colony formation and transwell assays, respectively. Targeted binding between miR-22-3p and LINC01137 was verified using a dual luciferase reporter assay. RESULTS: We found that LINC01137 was significantly upregulated in primary OSCCs. LINC01137 knockdown inhibited OSCC cell proliferation, migration and invasion, whereas LINC01137 overexpression induced opposite effects. LINC01137 upregulation along with p53 inhibition enhanced the malignant transformation of oral cells. In addition, we found that miR-22-3p can directly target LINC01137 through interaction with a putative miR-22-3p-binding site present within the LINC01137 sequence. A significant negative correlation was observed between LINC01137 and miR-22-3p expression in primary OSCC specimens. Exogenous overexpression of miR-22-3p markedly reduced the endogenous expression level of LINC01137 in OSCC cells. Additional functional assays showed that miR-22-3p overexpression enhanced the inhibitory effect of siRNA-mediated LINC01137 silencing on OSCC cell proliferation, migration and invasion, whereas miR-22-3p inhibition had the opposite effect. CONCLUSIONS: Our results indicate that LINC01137 functions as an oncogenic lncRNA in OSCC. miR-22-3p can directly target LINC01137 and negatively regulate its expression and function.

Blocking of the PD-1/PD-L1 interaction by a novel cyclic peptide inhibitor for cancer immunotherapy.

The interaction of PD-1/PD-L1 allows tumor cells to escape from immune surveillance. Clinical success of the antibody drugs has proven that blockade of PD-1/PD-L1 pathway is a promising strategy for cancer immunotherapy. Here, we developed a cyclic peptide C8 by using Ph.D.-C7C phage display technology. C8 showed high binding affinity with hPD-1 and could effectively interfere the interaction of PD-1/PD-L1. Furthermore, C8 could stimulate CD8+ T cell activation in human peripheral blood mononuclear cells (PBMCs). We also observed that C8 could suppress tumor growth in CT26 and B16-OVA, as well as anti-PD-1 antibody resistant B16 mouse model. CD8 T cells infiltration significantly increased in tumor microenvironment, and IFN-γ secretion by CD8+ T cells in draining lymph nodes also increased. Simultaneously, we exploited T cells depletion models and confirmed that C8 exerted anti-tumor effects via activating CD8+ T cells dependent manner. The interaction model of C8 with hPD-1 was simulated and confirmed by alanine scanning. In conclusion, C8 shows anti-tumor capability by blockade of PD-1/PD-L1 interaction, and C8 may provide an alternative candidate for cancer immunotherapy.

Y-box binding protein 1 (YB-1) promotes gefitinib resistance in lung adenocarcinoma cells by activating AKT signaling and epithelial-mesenchymal transition through targeting major vault protein (MVP).

PURPOSE: Gefitinib is a first-line treatment option for epidermal growth factor receptor (EGFR)-mutated lung adenocarcinoma. However, most patients inevitably develop gefitinib resistance. The mechanism underlying this resistance is not fully understood. Y-box binding protein 1 (YB-1) has been reported to play a role in modulating drug sensitivity, but its role in gefitinib resistance is currently unknown. Here, we investigated the role of YB-1 in gefitinib resistance of lung adenocarcinoma. METHODS: We determined the expression of YB-1, epithelial-mesenchymal transition (EMT) and AKT signaling markers, as well as the viability of lung adenocarcinoma cell lines bearing mutant (HCC827, PC-9) or wild-type (H1299) EGFR. We also evaluated PC-9 cell migration and invasion using transwell assays. The clinical importance of YB-1 and major vault protein (MVP) was evaluated using primary lung adenocarcinoma patient samples. RESULTS: We found that YB-1 was significantly upregulated in gefitinib-resistant lung adenocarcinoma cells compared to gefitinib-sensitive cells. YB-1 augmented gefitinib resistance by activating the AKT pathway and promoting EMT. Decreased migration and invasion was observed upon MVP silencing in YB-1-overexpressing PC-9 cells, as well as restored gefitinib sensitivity. A retrospective analysis of 85 patients with lung adenocarcinoma revealed that YB-1 levels were significantly increased in tyrosine kinase inhibitor (TKI)-resistant patients compared to those in TKI-sensitive patients, indicating that YB-1 may serve as a biomarker to clinically predict acquired gefitinib resistance. CONCLUSION: YB-1 activates AKT signaling and promotes EMT at least in part by directly activating MVP. Hence, targeting the YB-1/MVP axis may help to overcome gefitinib resistance in lung adenocarcinoma patients.

Long non­coding RNA FEZF1­AS1 facilitates non­small cell lung cancer progression via the ITGA11/miR­516b­5p axis.

Long non­coding RNAs (lncRNAs) have emerged as key players in the development and progression of cancer. FEZ family zinc finger 1 antisense RNA 1 (FEZF1­AS1) is a novel lncRNA that is involved in the development of cancer and acts as a potential biomarker for cancer. However, the clinical significance and molecular mechanism of FEZF1­AS1 in non­small cell lung cancer (NSCLC) remains uncertain. In the present study, FEZF1­AS1 was selected using Arraystar Human lncRNA microarray and was identified to be upregulated in NSCLC tissues and negatively associated with the overall survival of patients with NSCLC. Loss­of­function assays revealed that FEZF1­AS1 inhibition decreased cell proliferation and migration, and arrested cells at the G2/M cell cycle phase. Mechanistically, FEZF1­AS1 expression was influenced by N6­methyladenosine (m6A) modification. Since FEZF1­AS1 was mainly located in the cytoplasmic fraction of NSCLC cells, it was hypothesized that it may be involved in competing endogenous RNA regulatory network to impact the prognosis of NSCLC. Via integrating Arraystar Human mRNA microarray data and miRNA bioinformatics analysis, it was revealed that ITGA11 expression was decreased with loss of FEZF1­AS1 and increased with gain of FEZF1­AS1 expression, and microRNA (miR)­516b­5p inhibited the expression levels of both FEZF1­AS and ITGA11. RNA­binding protein immunoprecipitation and RNA pulldown assays further demonstrated that FEZF1­AS1 could bind to miR­516b­5p and that ITGA11 was a direct target of miR­516b­5p by luciferase reporter assay. Overall, the present findings demonstrated that FEZF1­AS1 was upregulated and acted as an oncogene in NSCLC by regulating the ITGA11/miR­516b­5p axis, suggesting that FEZF1­AS1 may be a potential prognostic biomarker and therapeutic target for NSCLC.

Lung adenocarcinoma-related TNF-α-dependent inflammation upregulates MHC-II on alveolar type II cells through CXCR-2 to contribute to Treg expansion.

MHC-II on alveolar type-II (AT-II) cells is associated with immune tolerance in an inflammatory microenvironment. Recently, we found TNF-α upregulated MHC-II in AT-II in vitro. In this study, we explored whether TNF-α-mediated inflammation upregulates MHC-II on AT-II cells to trigger Treg expansion in inflammation-driven lung adenocarcinoma (IDLA). Using urethane-induced mice IDLA model, we found that IDLA cells mainly arise from AT-II cells, which are the major source of MHC-II. Blocking urethane-induced inflammation by TNF-α neutralization inhibited tumorigenesis and reversed MHC-II upregulation on tumor cells of AT-II cellular origin in IDLA. MHC-II-dependent AT-II cells were isolated from IDLA-induced Treg expansion. In human LA samples, we found high expression of MHC-II in tumor cells of AT-II cellular origin, which was correlated with increased Foxp3+ T cells infiltration as well as CXCR-2 expression. CXCR-2 and MHC-II colocalization was observed in inflamed lung tissue and IDLA cells of AT-II cellular origin. Furthermore, at the pro-IDLA inflammatory stage, TNF-α-neutralization or CXCR-2 deficiency inhibited the upregulation of MHC-II on AT-II cells in inflamed lung tissue. Thus, tumor cells of AT-II cellular origin contribute to Treg expansion in an MHC-II-dependent manner in TNF-α-mediated IDLA. At the pro-tumor inflammatory stage, TNF-α-dependent lung inflammation plays an important role in MHC-II upregulation on AT-II cells.

Expression, association with clinicopathological features and prognostic potential of CEP55, p-Akt, FoxM1 and MMP-2 in astrocytoma.

Centrosomal protein 55 (CEP55) is a member of the centrosomal-associated protein family and participates in the regulation of cytokinesis during cell mitosis. However, aberrant CEP55 protein expression has been observed in human tumors. In addition, CEP55 regulates the biological functions of tumors by inducing the Akt pathway and upregulating forkhead box protein M1 (FoxM1) and matrix metalloproteinase-2 (MMP-2). In the present study, the levels, clinicopathological features and prognostic potential of CEP55, phosphorylated Akt (p-Akt), FoxM1 and MMP-2 in astrocytoma were evaluated. CEP55, p-Akt, FoxM1 and MMP-2 levels were examined in 27 normal brain tissues and 262 astrocytoma tissues by using immunohistochemistry. Furthermore, Kaplan-Meier analysis and Cox proportional hazards models were applied to predict the prognosis of patients with astrocytoma. The results indicated that expression levels of CEP55 and other proteins were elevated in human astrocytoma compared with those in normal brain tissue. The levels of the selected proteins were increased as the tumor grade increased. Furthermore, CEP55 expression was positively correlated with p-Akt, FoxM1 and MMP-2 levels in astrocytoma. Overall survival analysis revealed that patient prognosis was associated with CEP55, p-Akt, FoxM1 and MMP-2 levels, as well as with the tumor grade and patient age. Furthermore, CEP55, FoxM1, tumor grade and patient age were independent prognostic factors in astrocytoma according to multivariate analysis. Taken together, the present results suggested that CEP55, p-Akt, FoxM1 and MMP-2 have crucial roles in the progression and prognosis of human astrocytoma and that CEP55 and FoxM1 may be potential therapeutic targets.

High mobility group box-1 protects against Aflatoxin G1-induced pulmonary epithelial cell damage in the lung inflammatory environment.

Aflatoxin G1 (AFG1) is a member of the carcinogenic aflatoxin family. Our previous studies indicated that oral administration of AFG1 caused tumor necrosis factor (TNF)-α-dependent inflammation that enhanced oxidative DNA damage in alveolar epithelial cells, which may be related to AFG1-induced lung carcinogenesis. High mobility group box-1 (HMGB1) is a nuclear DNA-binding protein; the intracellular and extracellular roles of HMGB1 have been shown to contribute to DNA repair and sterile inflammation. The role of HMGB1 in DNA damage in an aflatoxin-induced lung inflammatory environment was investigated in this study. Upregulation of HMGB1, TLR2, and RAGE was observed in AFG1-induced lung inflamed tissues and adenocarcinoma. Blocking AFG1-induced inflammation by neutralization of TNF-α inhibited the upregulation of HMGB1 in mouse lung tissues, suggesting that AFG1-induced TNF-α-dependent inflammation regulated HMGB1 expression. In the in vitro human pulmonary epithelial cell line model, Beas-2b, AFG1 directly enhanced the cytosolic translocation of HMGB1 and its extracellular secretion. The addition of extracellular soluble HMGB1 protected AFG1-induced DNA damage through the TLR2/NF-κB pathway in Beas-2b cells. In addition, blockade of endogenous HMGB1 by siRNA significantly enhanced AFG1-induced damage. Thus, our findings showed that both extracellularly-released and nuclear and cytosolic HMGB1 could protect the cell from AFG1-induced cell damage in a TNF-α-dependent lung inflammatory environment.

MicroRNA-153-3p regulates cell proliferation and cisplatin resistance via Nrf-2 in esophageal squamous cell carcinoma.

BACKGROUND: Our recent studies have indicated that miR-153-3p is downregulated in the esophageal squamous cell carcinoma (ESCC) cell lines and tissues. Upregulation of miR-153-3p was found to inhibit migration and invasion of ESCC cells. However, whether miR-153-3p regulates the cisplatin sensitivity in ESCC cells remains unclear. In this study, we explored whether and how miR-153-3p regulates the proliferation and confers cisplatin resistance in ESCC by targeting the Nrf-2 protein. METHODS: Eca109 cell line was transfected with microRNA-153-3p mimics or Nrf-2siRNA and cell proliferation and cisplatin resistance were studied. A dual-luciferase reporter assay was performed on Eca109 cells cotransfected with the wild-type/mutant 3'UTR sequences of Nrf-2 and control or microRNA-153-3p mimics. We determined the correlation between microRNA-153-3p and Nrf-2 expression in human ESCC samples and explored the effect of Nrf-2 in the overall survival rate of ESCC patients. RESULTS: MiR-153-3p significantly suppressed cell proliferation and increased the sensitivity of Eca-109 cells to cisplatin. MiR-153-3p showed a negative correlation with Nrf-2 in human esophageal carcinoma tissues. MiR-153-3p suppressed the expression of Nrf-2 via binding to its 3'-UTR region. Furthermore, inhibition of Nrf-2 also decreased cell proliferation and increased the sensitivity of Eca109 cells to cisplatin. High expression of Nrf-2 in human ESCC samples was associated with poor overall survival of ESCC patients. CONCLUSION: MiR-153-3p inhibits cell proliferation and confers cisplatin resistance by downregulating Nrf-2 expression in Eca-109 cells. Thus, miR-153-3p/Nrf-2 may play an important role in conferring cisplatin resistance in ESCC. Nrf-2 appears to be a promising therapeutic target for ESCC.

ETV4 overexpression promotes progression of non-small cell lung cancer by upregulating PXN and MMP1 transcriptionally.

ETS variant 4 (ETV4), together with ETV1 and ETV5, constitute the PEA3 subfamily of ETS transcription factors, which are implicated in the progression of many cancers. However, the clinicopathologic significance and molecular events regulated by ETV4 in lung cancer are still poorly understood, especially in squamous cell carcinoma of the lung. Here, we aimed to identify functional targets involved in ETV4-driven lung tumorigenesis. Microarray analysis and validation data revealed that ETV4 was the most preponderant PEA3 factor, which was significantly related to the advanced stage, lymph node metastasis, and poor prognosis of non-small cell lung cancers (NSCLCs; all P < .001). Reduced ETV4 expression suppressed the growth and metastasis of NSCLC both in vivo and in vitro. Microarray, gain, or loss of function and luciferase report assays revealed the direct regulatory effect of ETV4 on the expression of focal adhesion gene PXN and matrix metalloproteinase 1 (MMP1), and PXN and/or MMP1 inhibition partially abolished cell proliferation and migration induced by ETV4. Kaplan-Meier analysis indicated that ETV4 and PXN or MMP1 co-overexpression is associated with poor prognosis in human NSCLCs. In conclusion, the ETV4-PXN and ETV4-MMP1 axes are useful biomarkers of tumor progression and worse outcomes in NSCLCs.

TNF­α­mediated upregulation of SOD­2 contributes to cell proliferation and cisplatin resistance in esophageal squamous cell carcinoma.

Intrinsic and acquired resistance of cancer to radio­and chemotherapy is one of the major challenges in the treatment of esophageal squamous cell carcinoma (ESCC). Elevated reactive oxygen species (ROS) play an important role in the resistance to cisplatin in ESCCs. Super dismutase [Mn], mitochondrial (SOD­2), an important primary antioxidant enzyme located in mitochondria, could regulate ROS production. Our previous study showed that tumor necrosis factor­α (TNF­α)­mediated SOD­2 through NF­κB was involved in epithelial­mesenchymal transition and migration in A549 cells. Therefore, the present study aimed to identify if TNF­α mediated SOD­2 upregulation is involved in cisplatin resistance in ESCC. It was identified that a higher expression of SOD­2 in human ESCC samples was associated with TNF­α expression and poor overall survival in patients with ESCC, suggesting that SOD­2 may act as an oncogene in ESCC. To further confirm if TNF­α could upregulate SOD­2 to contribute to cell proliferation, the human ESCC cell line Eca­109 was treated with TNF­α in vitro. TNF­α could upregulate SOD­2 and induce cell proliferation in Eca109 cells, while blocking SOD­2 using small interfering RNA (siRNA) inhibited TNF­α­induced cell proliferation. Upregulation of SOD­2 by TNF­α was inhibited by blocking the NF­κB pathway, which suggested that SOD­2 by TNF­α/NF­κB contributes to cell proliferation in Eca109 cells. Furthermore, it was observed that TNF­α could induce cisplatin resistance in Eca109 cells, while transfection with SOD­2 siRNA could significantly increase the chemosensitivity of ESCC to cisplatin. Therefore, the present results suggested that SOD­2 may serve as an oncogene, and the upregulation of SOD­2 by TNF­α/NF­κB may contribute to cisplatin resistance in ESCC.

Long noncoding RNA TP53TG1 promotes pancreatic ductal adenocarcinoma development by acting as a molecular sponge of microRNA-96.

Long noncoding RNAs (lncRNAs) are emerging as key regulators in cancer initiation and progression. TP53TG1 is a recently identified lncRNA and several studies have shown that TP53TG1 may play the role of tumor suppressor gene or oncogene in different tumors. Nevertheless, the involvement of TP53TG1 in carcinogenesis of pancreatic ductal adenocarcinoma (PDAC) has not been characterized. In our studies, we identified that TP53TG1 was highly expressed in PDAC and was a novel regulator of PDAC development. Knockdown of TP53TG1 inhibited proliferation, induced apoptosis, and decreased migration and invasion in PDAC cells, whereas enhanced expression of TP53TG1 had the opposite effects. Mechanistically, TP53TG1 could directly bind to microRNA (miR)-96 and effectively function as a sponge for miR-96, thus antagonizing the functions of miR-96 and leading to derepression of its endogenous target KRAS, which is a core oncogene in the initiation and maintenance of PDAC. Taken together, these observations imply that TP53TG1 contributes to the growth and progression of PDAC by acting as a competing endogenous RNA (ceRNA) to competitively bind to miR-96 and regulate KRAS expression, which highlights the importance of the complicated miRNA-lncRNA network in modulating the progression of PDAC.

Aflatoxin G1 induced TNF-α-dependent lung inflammation to enhance DNA damage in alveolar epithelial cells.

Aflatoxin G1 (AFG1 ), a member of the AF family with cytotoxic and carcinogenic properties, could cause DNA damage in alveolar type II (AT-II) cells and induce lung adenocarcinoma. Recently, we found AFG1 could induce chronic lung inflammation associated with oxidative stress in the protumor stage. Chronic inflammation plays a critical role in cigarette smoke or benzo[a]pyrene-induced lung tissues damage. However, it is unclear whether and how AFG1 -induced lung inflammation affects DNA damage in AT-II cells. In this study, we found increased DNA damage and cytochrome P450 (CYP2A13) expression in AFG1 -induced inflamed lung tissues. Furthermore, we treated the mice with a soluble tumor necrosis factor (TNF)-α receptor and AFG1 and found that TNF-α neutralization inhibited the AFG1 -induced chronic lung inflammation in vivo, and then reversed the CYP2A13 expression and DNA damage in AT-II cells. The results suggest that AFG1 induces TNF-α-dependent lung inflammation to regulate 2A13 expression and enhance DNA damage in AT-II cells. Then, we treated the primary mice AT-II cells and human AT-II like cells (A549) with AFG1 and TNF-α and found that TNF-α enhanced the AFG1 -induced DNA damage in mice AT-II cells as well as A549 cells in vitro. In AFG1 -exposed A549 cells, TNF-α-enhanced DNA damage and apoptosis were reversed by CYP2A13 small interfering RNA. Blocking NF-κB pathway inhibited the TNF-α-enhanced CYP2A13 upregulation and DNA damage confirming that the CYP2A13 upregulation by TNF-α plays an essential role in the activation of AFG1 under inflammatory conditions. Taken together, our findings suggest that AFG1 induces TNF-α-dependent lung inflammation, which upregulates CYP2A13 to promote the metabolic activation of AFG1 and enhance oxidative DNA damage in AT-II cells.