Retraction notice to "HIF-1α mediates tumor-nerve interactions through the up-regulation of GM-CSF in pancreatic ductal adenocarcinoma" [Cancer Lett. 453 (2019) 10-20].

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal). This article has been retracted at the request of the Editor-in-Chief and Authors. Following concerns raised in the public domain, the authors contacted the journal to request the retraction of the article. Sections of panels from various figures appear similar to each other, particularly panels from Figs. 3G, 5B and 3G and 5F, 3F, S4D, S5D, S5C and S10C, as well as S10E.

Improved method to stratify lymphoma patients with risk of secondary central nervous system involvement: A multicenter retrospective analysis.

Secondary central nervous system (SCNS) involvement is an infrequent but universally fatal event in diffused large B-cell lymphoma. The occurrence rate of SCNS involvement is approximately 5% but comes with a poor prognosis ever after. However, existing risk models to predict the incidence and prognosis of these patients with SCNS involvement lack both efficiency and accuracy. Controversy has also been reported regarding which risk factor may best identify the population with a high CNS relapse rate. In this study, we retrospectively analyzed 831 patients with diffused large B-cell lymphoma, diagnosed between March 2008 and June 2018 in Tianjin Medical University Cancer Institute and Hospital, Beijing Cancer Hospital, and Cancer Hospital of The University of Chinese Academy of Science. Risk factors and nomogram were identified and established based on Fine and Gray's competing risk analysis. Among these patients, 55 (6.6%) of them eventually developed SCNS involvement. The 1- and 2-year incidence for SCNS involvement were 3.9% and 4.7%, respectively. The median time from de novo diagnosis to CNS relapse was 8 months, and the median overall survival of these patients was 28 months. Considering the competing mortality before SCNS involvement, Fine and Gray's competing risk model was performed to analyze the characteristics related to SCNS involvement, and identified risk factors as the multiple extranodal involvements, elevated LDH and AMC level, and the involvement of breast, adrenal gland/kidney, pulmonary and bone. Corresponding factors were integrated into the competing nomogram for SCNS involvement (c-index = 0.778). In conclusion, we present the first predictive nomogram to evaluate the risk to develop SCNS involvement in de novo DLBCL patients, which may help in both prognostic evaluation and clinical decision for this subgroup.

SOX8 Affects Tumoral SPARC Expression by Regulating EZH2 to Attenuate Effectiveness of albumin-bound paclitaxel in PDAC.

Pancreatic cancer is a dismal malignancy with poor prognosis. In spite of progress in surgical technology, chemotherapy is still the cornerstone in the multi-disciplinary treatment. Albumin-bound paclitaxel is a first-line treatment for PDAC patients. Yet the response rate of the drug is far from satisfying. SOX8 is a member of the sex determining region Y-boxes family, which is potentially related to the chemoresistance of tumor. Patient with high expression of SOX8 were insensitive to albumin-bound paclitaxel. SOX8 reduced apoptosis and G2/M cell cycle arrest caused by albumin-bound paclitaxel. SOX8 transcriptionally regulated EZH2, which reduced expression of SPARC by promoting the methylation of SPARC, thereby reducing the transport of albumin-bound paclitaxel in pancreatic cancer cells. EZH2 inhibitor, UNC1999, can reverse the effect of SOX8 on chemo-resistance of albumin-bound paclitaxel. Collectively, our data revealed SOX8/EZH2/SPARC signaling induced primary chemo-resistance of albumin-bound paclitaxel in pancreatic ductal adenocarcinoma.

Influence of Interactions between Nitrogen, Phosphorus Supply and Epichloёbromicola on Growth of Wild Barley (Hordeum brevisubulatum).

Epichloë endophytes are biotrophic fungi that establish mutualistic symbiotic relationship with grasses and affect performance of the host under different environments. Wild barley (Hordeum brevisubulatum) is an important forage grass and often infected by Epichloë bromicola, thus showing tolerances to stresses. Since the plant growth correlates with both microbial infection and nutrient stoichiometry, this study was performed to investigate whether the function of Epichloë bromicola endophyte to improve host growth depend upon the nitrogen (N), phosphorus (P) fertilization. Epichloë-infected (E+) and Epichloë-free (E-) wild barley plants were subjected to nine types of mixed N (0.2 mM, 3 mM, 15 mM) and P (0.01 mM, 0.1 mM, 1.5 mM) levels treatments for 90 d to collect plant samples and determine multiple related indexes. We found that E. bromicola and N, P additions positively affected seed germination. Further, E. bromicola significantly enhanced chlorophyll content and root metabolic activity under N-deficiency, and meanwhile, might alter allocation of photosynthate under different conditions. The contents of N, P and stoichiometry of C:N:P of E+ plants were significantly higher than that of E- under nutrient deficiency, but contrary results were observed under adequate nutrients. Therefore, we propose that the growth-promoting ability of E. bromicola is closely correlated with N and P additional levels. Under low N, P additions, positive roles of endophyte are significant as opposed to negative roles under high N, P additions.

HIF-1α mediates tumor-nerve interactions through the up-regulation of GM-CSF in pancreatic ductal adenocarcinoma.

Perineural invasion (PNI) is a typical pathological feature of pancreatic ductal adenocarcinoma (PDAC). PNI is associated with poor prognosis of PDAC patients, however, the underlying molecular mechanisms in the development of PNI have not been fully revealed. In this study, we found that the expression of GM-CSF and HIF-1α were dramatically increased in PDAC cells. The overexpression of HIF-1α and GM-CSF closely correlated with increased occurrence of PNI and cancer-related pain and shortened overall survival in PDAC patients. GM-CSF expression in PDAC cells was mediated by HIF-1α through direct binding to the hypoxia response element in the GM-CSF promoter. The activated HIF-1α can up-regulate GM-CSF expression and secretion, which promoted the migration of Schwann cells in tumor microenvironment. Furthermore, GM-CSF overexpression could rescue the inhibition of Schwann cells migration by HIF-1α knockdown. Moreover, HIF-1α inhibition with PX478 drastically reduced the expression level of GM-CSF and decreased the PNI in a PDAC xenograft mouse model. Overall, our results demonstrated that the HIF-1α/GM-CSF pathway is involved in the tumor-nerve interactions and promotes the occurrence of PNI. The blockade of this signal might help to inhibit PDAC progression.

Immunochemotherapeutic increase of peripheral absolute monocyte count predicts interstitial pneumonia in lymphoma patients.

Interstitial pneumonia (IP) is one of the potentially fatal adverse events for lymphoma patients undergoing immunochemotherapy. However, the risk factors and predictive markers remain unclear for this complication. This retrospective study aims to explore whether the change of absolute monocyte count (AMC) during immunochemotherapy is correlated with IP occurrence and progression. A total of 500 lymphoma patients receiving immunochemotherapy from 2014 to 2016 were enrolled in this investigation. Interstitial pneumonia was generally diagnosed as diffused pulmonary interstitial infiltrates on computed tomography images in conjunction with respiratory symptoms or pulmonary function test, which is also adopted as a diagnosing tool of IP in this study. Among the total 500 participating patients, 40 patients were diagnosed as IP, which account for 8% of the total subjects. The median number of chemotherapy cycles for those patients prior to IP occurrence is 4. This research suggests that the increase of peripheral AMC over 0.565 × 109 /L after 2 cycles of immunochemotherapy is a great potential to develop IP. Using the method of multivariate analysis, lymphoma lung involvement and high AMC after 2 cycles of immunochemotherapy were identified as independent risk factors for IP. Most IP patients with sustained AMC elevation (>0.575 × 109 /L at IP onset) accompanied severe pulmonary symptoms, while those with AMC fall-back might tolerate subsequent immunochemotherapy. Thus, this study concludes that early increase of AMC during immunochemotherapy in lymphoma patients with lung involvement suggested a great potential to develop IP. Dynamic changes in AMC may serve as a predictive marker for IP severity and a guide for treatment adjustment for both tumor and pulmonary injuries.

HIF-2-dependent expression of stem cell factor promotes metastasis in hepatocellular carcinoma.

Stem cell factor (SCF) is a multifunctional cytokine responsible for tumorigenesis and progression. In this study, we report that increased expression of SCF in hepatocellular carcinoma (HCC) patients is highly associated with metastasis and poor prognosis. SCF inhibition with RNAi inhibited HCC cell migration, invasion in vitro, and reduced intrahepatic metastases burden and significantly prolonged survival in a HCC xeograft mouse model. SCF depletion in HCC xeograft decreased the expression of vimentin and increase the expression of E-cadherin, implicating a role for SCF in epithelial-mesenchymal transition. Our data further demonstrated that HCC cells secreted soluble SCF to promote HUVECs angiogenesis. The overexpression of SCF in HCC is regulated by hypoxic conditions through a selective HIF-2α-dependent mechanism. Knocking-down HIF-2α significantly decreased expression of SCF. Chromatin immunoprecipitation and luciferase assay demonstrated that HIF-2α directly induce the transcription of SCF gene through the hypoxia response element in SCF promoter. In conclusion, we demonstrate that the hypoxia microenvironment in HCC up-regulates SCF expression, which in turn promotes angiogenesis and HCC metastasis.

Hypoxia Inducible Factor 1 (HIF-1) Recruits Macrophage to Activate Pancreatic Stellate Cells in Pancreatic Ductal Adenocarcinoma.

Hypoxia inducible factor 1 (HIF-1) is a transcription factor composed of two subunits, namely, HIF-1α and HIF-1ß, in which HIF-1ß is constitutively expressed. HIF-1 upregulates several hypoxia-responsive proteins, including angiogenesis factors, glycolysis solution enzymes, and cell survival proteins. HIF-1 is also associated with the degree of inflammation in the tumor region, but the exact mechanism remains unclear. This study aims to identify the molecular mechanism of recruiting monocytes/macrophages by HIF-1α in pancreatic ductal adenocarcinoma (PDAC) and the effects of macrophages on pancreatic stellate cells (PSCs). Immunohistochemistry (IHC) was performed for cluster of differentiation 68 (CD68), HIF-1α, and chemical chemokines 2 (CCL2). Western blot, real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR), chromatin immunoprecipitation assay, and The Cancer Genome Atlas (TCGA) were used to verify the correlation between HIF-1α and CCL2 at protein and nucleic acid levels. Monocytes/macrophages were co-cultured with PSCs to observe their interaction. Samples showed significant correlation between CD68 and HIF-1α (t-test, p < 0.05). HIF-1α recruited monocytes/macrophages by promoting CCL2 secretion. Moreover, macrophages could accelerate the activation of PSCs. HIF-1α might promote inflammation and fibrosis of PDAC through CCL2 secretion, which may provide a novel target to treat PDAC patients.

Arsenic trioxide plus PX-478 achieves effective treatment in pancreatic ductal adenocarcinoma.

Arsenic trioxide (ATO) has been selected as a promising treatment not only in leukemia but also in solid tumors. Previous studies showed that the cytotoxicity of ATO mainly depends on the induction of reactive oxygen species. However, ATO has only achieved a modest effect in pancreatic ductal adenocarcinoma, suggesting that the existing radical scavenging proteins, such as hypoxia inducible factor-1, attenuate the effect. The goal of this study is to investigate the effect of combination treatment of ATO plus PX-478 (hypoxia-inducible factor-1 inhibitor) and its underlying mechanism. Here, we showed that PX-478 robustly strengthened the anti-growth and pro-apoptosis effect of ATO on Panc-1 and BxPC-3 pancreatic cancer cells in vitro. Meanwhile, in vivo mouse xenograft models also showed the synergistic effect of ATO plus PX-478 compared with any single agent. Further studies showed that the anti-tumor effect of ATO plus PX-478 was derived from the reactive oxygen species-induced apoptosis. We next confirmed that Hypoxia-inducible factor-1 cleared reactive oxygen species by its downstream target, forkhead box O transcription factors, and this effect may justify the strategy of ATO plus PX-478 in the treatment of pancreatic cancer.

SCF, regulated by HIF-1α, promotes pancreatic ductal adenocarcinoma cell progression.

Stem cell factor (SCF) and hypoxia-inducible factor-1α (HIF-1α) both have important functions in pancreatic ductal adenocarcinoma (PDAC). This study aims to analyze the expression and clinicopathological significance of SCF and HIF-1α in PDAC specimens and explore the molecular mechanism at PDAC cells in vitro and in vivo. We showed that the expression of SCF was significantly correlated with HIF-1α expression via Western blot, PCR, chromatin immunoprecipitation (ChIP) assay, and luciferase assay analysis. The SCF level was also correlated with lymph node metastasis and the pathological tumor node metastasis (pTNM) stage in PDAC samples. The SCF higher-expression group had significantly lower survival rates than the SCF lower-expression group (p<0.05). Hypoxia up-regulated the expression of SCF through the hypoxia-inducible factor (HIF)-1α in PDAC cells at the protein and RNA levels. When HIF-1α was knocked down by RNA interference, the SCF level decreased significantly. Additionally, ChIP and luciferase results demonstrated that HIF-1α can directly bind to the hypoxia response element (HRE) region of the SCF promoter and activate the SCF transcription under hypoxia. The results of colony formation, cell scratch, and transwell migration assay showed that SCF promoted the proliferation and invasion of PANC-1 cells under hypoxia. Furthermore, the down-regulated ability of cell proliferation and invasion following HIF-1α knockdown was rescued by adding exogenous SCF under hypoxia in vitro. Finally, when the HIF-1α expression was inhibited by digoxin, the tumor volume and the SCF level decreased, thereby proving the relationship between HIF-1α and SCF in vivo. In conclusion, SCF is an important factor for the growth of PDAC. In our experiments, we proved that SCF, a downstream gene of HIF-1α, can promote the development of PDAC under hypoxia. Thus, SCF might be a potential therapeutic target for PDAC.

Stem cell factor is a novel independent prognostic biomarker for hepatocellular carcinoma after curative resection.

Stem cell factor (SCF), a ligand of c-kit, is a hematopoietic growth factor. Uncontrolled activity of SCF/c-kit signaling pathway contributes to the formation of a variety of human malignancies. In this study, we determined whether SCF expression could risk-stratify patients with hepatocellular carcinoma (HCC) after curative resection. HCC tissues from 160 patients were collected during curative resection and stained with SCF and CD34, a marker for microvessel density (MVD), using immunohistochemistry. Two statistical analyses were performed: an independent continuous and a multivariate categorical analysis, with test/validation set-defined cut points, and Kaplan-Meier estimated outcome measures of overall survival (OS) and relapse-free survival (RFS). We found that higher levels of SCF confer worse OS (continuous P = 0.014; and categorical P = 0.009), and RFS (continuous P = 0.002; categorical P = 0.003) of patients with HCC. SCF varies independently from MVD-CD34, tumor node metastasis, histologic grade, age and gender, and retains prognostic significance when analysed as a categorical variable in a multivariate analysis . We confirmed that MVD-CD34 is also an independent prognostic marker for patients with HCC. The levels of SCF and CD34 showed a positive and significant correlation (P < 0.0001) and double low expression confers superior OS (median = 48 months) and RFS (median = 24 months), whereas double high expression confers shortest RFS (median = 10.5 months) compared with single measurements. The prognostic values of SCF and CD34 were independently determined in this study and we propose that both of them are independent prognostic markers for HCC.