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Physiological and histopathological effects of polystyrene nanoparticles on the filter-feeding fish Hypophthalmichthys molitrix

Excessive use of plastics in daily life is causing plastic pollution in aquatic environment and threatening the aquatic life. Therefore, research on the plastic pollution in aquatic environment is crucial to understand its impact and develop effective solution for safeguarding aquatic life and ecosystem. The current study investigated the effects of water borne polystyrene nanoparticles (PS-NPs) on hemato-immunological indices, serum metabolic enzymes, gills, and liver antioxidant parameters, plasma cortisol level and histopathological changes in liver and gill tissues of the widely distributed fish Hypophthalmichthys molitrix. The fingerlings of H. molitrix were exposed to different concentrations (T1-0.5, T2-1.0, and T3-2.0 mg/L) of PS-NPs respectively for 15 days consecutively. Our results indicated the dose dependent negative effects of PS-NPs on the physiology and histopathology of H. molitrix. Immuno-hematological indices showed significant increase in WBCs count, phagocytic activity, and lysozyme activity, while decreased RBC count, Hct%, Hb level, total proteins, IgM, and respiratory burst activity were observed. The levels of antioxidant enzymes like SOD, CAT and POD showed the decreasing trends while metabolic enzymes (AST, ALT, ALP and LDH), LPO, ROS activities and relative expressions of SOD1, CAT, HIF1-α and HSP-70 genes increased with increased concentrations of PS-NPs. Moreover, blood glucose and cortisol levels also showed significant increasing trends with dose dependent manner. Histopathological examination indicated moderate to severe changes in the gills and liver tissues of the group treated with 2.0 mg/L of PS-NPs. Overall, the results showed the deleterious effects of PS-NPs on physiology, immunity, metabolism, and gene expressions of H. molitrix. It is concluded that particulate plastic pollution has deleterious effects on filter feeding fish, which might affect human health through food chain and particulate chemical toxicity.

Molecular cloning and functional characterization of the hypoxia-inducible factor-1α in bighead carp (Aristichthys nobilis)

HIF-l is the earliest documented and most widely studied hypoxia-inducible factor (HIF) and plays a key role in the cell hypoxia signal transduction pathway. Particularly, the HIF-1α protein is sensitive to oxygen and plays a critical role in hypoxia regulation. This study is the first to report on the molecular cloning and characterization of HIF-1α in bighead carp (Aristichthys nobilis; anHIF-1α). The full-length cDNA of anHIF-1α was 2361 bp, and encodes an estimated 674 amino acids with a predicted molecular mass of 76.10 kDa and a theoretical isoelectric point of 7.72. Moreover, the conserved basic Helix-Loop-Helix domain along with two Per-ARNT-Sim domains (A/B), and C-TAD were identified in this protein. Interestingly, the tertiary structure of the anHIF-1α protein was found to be extremely similar to that of mice. Multiple comparison and phylogenetic tree results demonstrated that anHIF-1α was highly conserved. Under normoxic conditions, anHIF-1α mRNA transcripts could be detected in all tissues examined with the highest expression level in the heart. With gradually decreasing oxygen concentrations, anHIF-1α mRNA level was upregulated significantly in the gill, liver, kidney, spleen, intestine, brain, and muscle tissues (P < 0.05). Similarly, anHIF-1α was expressed in all examined bighead carp tissues, and the results suggested that the upregulation of anHIF-1α at the transcriptional level may be an important stress response adaptation to hypoxia in bighead carp. Finally, based on the tertiary structure comparative analyses between anHIF-1α with mouse HIF-1α, we think the physiological function, and protein structure of HIF-1α could be compared between fish and mammal in the future.

The HIF-1α antisense long non-coding RNA drives a positive feedback loop of HIF-1α mediated transactivation and glycolysis

Hypoxia-inducible factor-1 (HIF-1) is a master driver of glucose metabolism in cancer cells. Here, we demonstrate that a HIF-1α anti-sense lncRNA, HIFAL, is essential for maintaining and enhancing HIF-1α-mediated transactivation and glycolysis. Mechanistically, HIFAL recruits prolyl hydroxylase 3 (PHD3) to pyruvate kinase 2 (PKM2) to induce its prolyl hydroxylation and introduces the PKM2/PHD3 complex into the nucleus via binding with heterogeneous nuclear ribonucleoprotein F (hnRNPF) to enhance HIF-1α transactivation. Reciprocally, HIF-1α induces HIFAL transcription, which forms a positive feed-forward loop to maintain the transactivation activity of HIF-1α. Clinically, high HIFAL expression is associated with aggressive breast cancer phenotype and poor patient outcome. Furthermore, HIFAL overexpression promotes tumor growth in vivo, while targeting both HIFAL and HIF-1α significantly reduces their effect on cancer growth. Overall, our results indicate a critical regulatory role of HIFAL in HIF-1α-driven transactivation and glycolysis, identifying HIFAL as a therapeutic target for cancer treatment.

3D bioprinted glioma cell-laden scaffolds enriching glioma stem cells via epithelial-mesenchymal transition

Glioma stem cells (GSCs) are thought to be the root cause of tumor recurrence and drug resistance in glioma patients. In-depth study of GSCs is of great significance for developing the treatment strategies of glioma. Unfortunately, it is difficult and takes complicated process to obtain GSCs. Therefore, establishing an ideal in vitro model for enriching GSCs will greatly promote the study of GSCs. In this study, the stemness properties of glioma cells were enhanced in three-dimensional (3D) bioprinted tumor model. Furthermore, the possible molecular mechanism of GSCs enrichment: epithelial-mesenchymal transition (EMT) was explored. Compared with two-dimensional cultured cells, the proportion of GSCs and EMT-related genes in 3D cultured cells were significantly increased. Moreover, the 3D cultured glioma cells with improved stemness properties resulted in higher drug resistance in vitro and tumorigenicity in vivo. Taken together, 3D bioprinted glioma cell-laden scaffold provides a proper platform for the enrichment of GSCs and it is expected to further promote the research on glioma drug resistance. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 107A: 383-391, 2019.

Targeting hexokinase 2 inhibition promotes radiosensitization in HPV16 E7-induced cervical cancer and suppresses tumor growth

In order to improve the sensitivity of cervical cancer cells to irradiation therapy, we targeted hexokinase 2 (HK2), the first rate-limiting enzyme of glycolysis, and explore its role in cervical cancer cells. We suppressed HK2 expression and/or function by shRNA and/or metformin and found HK2 inhibition enhanced cells apoptosis with accelerating expression of cleaved PARP and caspase-3. HK2 inhibition also induced much inferior proliferation of cervical cancer cells both in vitro and in vivo with diminishing expression of mTOR, MIB and MGMT. Moreover, HK2 inhibition altered the metabolic profile of cervical cancer cells to one less dependent on glycolysis with a reinforcement of mitochondrial function and an ablation of lactification ability. Importantly, cervical cancer cells contained HK2 inhibition displayed more sensitivity to irradiation. Further results indicated that HPV16 E7 oncoprotein altered the glucose homeostasis of cervical cancer cells into glycolysis by coordinately promoting HK2 expression and its downregulation of glycolysis. Taken together, our findings supported a mechanism whereby targeting HK2 inhibition contributed to suppress HPV16 E7-induced tumor glycolysis metabolism phenotype, inhibiting tumor growth, and induced apoptosis, blocking the cancer cell energy sources and ultimately enhanced the sensitivity of HPV(+) cervical cancer cells to irradiation therapy.

Ras oncogene and Hypoxia-inducible factor-1 alpha (hif-1α) expression in the Amazon fish Colossoma macropomum (Cuvier, 1818) exposed to benzo[a]pyrene

Benzo[a]pyrene (B[a]P) is a petroleum derivative capable of inducing cancer in human and animals. In this work, under laboratory conditions, we analyzed the responses of Colossoma macropomum to B[a]P acute exposure through intraperitoneal injection of four different B[a]P concentrations (4, 8, 16 and 32 μmol/kg) or corn oil (control group). We analyzed expression of the ras oncogene and the Hypoxia-inducible factor-1 alpha (hif-1α) gene using quantitative real-time PCR. Additionally, liver histopathological changes and genotoxic effects were evaluated through the comet assay. Ras oncogene was overexpressed in fish exposed to 4, 8 of 16 μmol/kg B[a]P, showing 4.96, 7.10 and 6.78-fold increases, respectively. Overexpression also occurred in hif-1α in fish injected with 4 and 8 μmol/kg B[a]P, showing 8.82 and 4.64-fold increases, respectively. Histopathological damage in fish liver was classified as irreparable in fish exposed to 8, 16 and 32 μmol/kg μM B[a]P. The genotoxic damage increased in fish injected with 8 and 16 μmol/kg in comparison with the control group. Acute exposure of B[a]P was capable to interrupt the expression of ras oncogene and hif-1α, and increase DNA breaks due to tissue damage.

Genetic polymorphisms in key hypoxia-regulated downstream molecules and phenotypic correlation in prostate cancer

Background

In this study we sought if, in their quest to handle hypoxia, prostate tumors express target hypoxia-associated molecules and their correlation with putative functional genetic polymorphisms.

Methods

Representative areas of prostate carcinoma (n = 51) and of nodular prostate hyperplasia (n = 20) were analysed for hypoxia-inducible factor 1 alpha (HIF-1α), carbonic anhydrase IX (CAIX), lysyl oxidase (LOX) and vascular endothelial growth factor (VEGFR2) immunohistochemistry expression using a tissue microarray. DNA was isolated from peripheral blood and used to genotype functional polymorphisms at the corresponding genes (HIF1A +1772 C > T, rs11549465; CA9 + 201 A > G; rs2071676; LOX +473 G > A, rs1800449; KDR – 604 T > C, rs2071559).

Results

Immunohistochemistry analyses disclosed predominance of positive CAIX and VEGFR2 expression in epithelial cells of prostate carcinomas compared to nodular prostate hyperplasia (P = 0.043 and P = 0.035, respectively). In addition, the VEGFR2 expression score in prostate epithelial cells was higher in organ-confined and extra prostatic carcinoma compared to nodular prostate hyperplasia (P = 0.031 and P = 0.004, respectively). Notably, for LOX protein the immunoreactivity score was significantly higher in organ-confined carcinomas compared to nodular prostate hyperplasia (P = 0.015). The genotype-phenotype analyses showed higher LOX staining intensity for carriers of the homozygous LOX +473 G-allele (P = 0.011). Still, carriers of the KDR−604 T-allele were more prone to have higher VEGFR2 expression in prostate epithelial cells (P < 0.006).

Conclusions

Protein expression of hypoxia markers (VEGFR2, CAIX and LOX) on prostate epithelial cells was different between malignant and benign prostate disease. Two genetic polymorphisms (LOX +473 G > A and KDR−604 T > C) were correlated with protein level, accounting for a potential gene-environment effect in the activation of hypoxia-driven pathways in prostate carcinoma. Further research in larger series is warranted to validate present findings.

Electronic supplementary material

The online version of this article (doi:10.1186/s12894-017-0201-y) contains supplementary material, which is available to authorized users.

Expression and clinical significance of glucose transporter-1 in pancreatic cancer

Increasing evidence has demonstrated that malignant cells exhibit increased glucose uptake, which facilitates survival and growth in a hypoxic environment. The glucose transporter-1 (GLUT-1) is overexpressed in a variety of malignant tumors. However, the association between GLUT-1 expression and clinicopathological factors, ¹⁸F-fluorodeoxyglucose uptake and tumor proliferation in pancreatic cancer has not been investigated to date. In the present study, the expression of GLUT-1 in 53 pancreatic cancer tissues was analyzed, which revealed that GLUT-1 was overexpressed in pancreatic tissue and correlated with poor prognosis and clinicopathological characteristics, including increased tumor size, clinical stage and lymph node metastasis, maximum standardized uptake value (SUV_max) and Ki-67 expression. The receiver operating characteristic curve analysis indicated that a cut-off SUV_max value of 4.830 was associated with optimal sensitivity (88%) and specificity (71.4%) for the detection of strong positive GLUT-1 expression. In addition, as the expression of GLUT-1 was found to correlate with Ki-67 expression, GLUT-1 may exhibit a significant effect on cell proliferation in pancreatic cancer. Overall, these findings indicate that GLUT-1 may represent a prognostic indicator, and a potential therapeutic target for pancreatic cancer.

Local recurrence of small cell lung cancer following radiofrequency ablation is induced by HIF-1α expression in the transition zone

Local recurrence of lung cancer following radiofrequency ablation (RFA) treatment is common. The aims of the present study were to assess how RFA treatment affects the growth of small cell lung cancer (SCLC) micrometastases in the transition zone (TZ) surrounding the ablated region and in the reference zones (RZs) of the ablated or unablated lobes and to identify the molecular mechanism(s) of lung cancer recurrence following RFA treatment. After lung micrometastases of human SCLCs had formed, RFA treatment was applied to the right upper lobe (RUL) of the lung in nude mice. Hypoxia inducible factor (HIF)-1α expression, proliferation and angiogenesis potential both in the TZ and RZ were evaluated over time. Separately, at day 1, 7 and 14 following RFA treatment, the growth of micrometastases showed an ~2-fold increase in the TZ compared to the RZ of the unablated lobe, as the right lower lobe (RLL) and the growth of micrometastases in the RZ of the RUL was also induced by RFA. In addition, accelerated tumor growth in the TZ was induced by HIF-1α, but was not associated with tissue angiogenesis potential. We concluded that local recurrences of SCLCs caused by overproliferation of micrometastases following RFA treatment were driven by HIF-1α, although angiogenesis was not the driving force in the TZ.

Hypoxia induced high expression of thioredoxin interacting protein (TXNIP) in non-small cell lung cancer and its prognostic effect

Although associations between thioredoxin interacting protein (TXNIP) and cancers have been recognized, the effects of TXNIP on non-small cell lung cancer (NSCLC) prognosis remained to be determined in detail. In addition, while hypoxia is a key characteristic of tumor cell growth microenvironment, the effect of hypoxia on TXNIP expression is controversial. In this study, formaldehyde fixed and paraffin embedded (FFPE) samples of 70 NSCLC patients who underwent resection between January 2010 and December 2011 were obtained. Evaluation of TXNIP and hypoxia inducible factor-1α (HIF-1α) protein expression in FFPE samples was made by immunohistochemistry. By Kaplan-Meier method, patients with high TXNIP expression demonstrated a significantly shorter progression free survival (PFS) compared with those with low TXNIP expression (18.0 months, 95%CI: 11.7, 24.3 versus 23.0 months, 95%CI: 17.6, 28.4, P=0.02). High TXNIP expression level was also identified as an independent prognostic factor by Cox regression analysis (adjusted hazard ratio: 2.46; 95%CI: 1.08, 5.56; P=0.03). Furthermore, TXNIP expression was found to be significantly correlated with HIF- 1α expression (Spearman correlation=0.67, P=0.000). To further confirm correlations, we established a tumor cell hypoxic culture model. Expression of TXNIP was up-regulated in all three NSCLC cell lines (A549, SPC-A1, and H1299) under hypoxic conditions. This study suggests that hypoxia induces increased TXNIP expression in NSCLC and high TXNIP expression could be a poor prognostic marker.

Hypoxia and Prostate Cancer Aggressiveness: A Tale With Many Endings

Angiogenesis, increased glycolysis, and cellular adaptation to hypoxic microenvironment are characteristic of solid tumors, including prostate cancer. These representative features are the cornerstone of cancer biology, which are well correlated with invasion, metastasis, and lethality, as well as likely with the success of prostate cancer treatment (eg, tumor hypoxia has been associated with resistance to chemotherapy and radiotherapy). It is well established that prostate cancer cells also metabolically depend on enhanced glucose transport and glycolysis for expansion, whereas growth is contingent with neovascularization to permit diffusion of oxygen and glucose. While hypoxia inducible factor 1 alpha (HIF-1α) remains the central player, the succeeding activated molecules and pathways track distinct branches, all positively correlated with the degree of intratumoral hypoxia. Among these, the vascular endothelial growth factor axis as well as the lysyl oxidase and carbonic anhydrase IX activities are notable in prostate cancer and merit further study. Here, we demonstrate their linkage with HIF-1α as a tentative explanatory mechanism of prostate cancer aggressiveness. Hypoxia drives a tale where HIF-1α-dependent effects lead to many influences in distinct key cancer biology features, rendering targeted therapies toward targets at the endings less efficient. The most appropriate approach will be to inhibit the upstream common driver (HIF-1α) activity. Additional translational and clinical research initiatives in prostate cancer are required to prove its usefulness.

SOCS3 blocks HIF-1α expression to inhibit proliferation and angiogenesis of human small cell lung cancer by downregulating activation of Akt, but not STAT3

Suppressor of cytokine signaling 3 (SOCS3) is a major negative regulator of signal transducer and activator of transcription 3 (STAT3) during tumorigenesis. Previous studies have indicated that SOCS3 also regulates other signaling pathways, such as PI3K/Akt. However, little is known about the specific molecular mechanisms by which SOCS3 regulates the proliferation and angiogenesis of small cell lung cancer (SCLC) cells. The present study investigated the effect of SOCS3 upregulation on the expression of hypoxia-inducible factor-1α (HIF-1α) and how this affects the proliferation and angiogenesis of SCLC cells. It was investigated whether this interaction is associated with STAT3 or the Akt signaling pathway. The results of the present study revealed that SOCS3 negatively regulates proliferation and angiogenesis of NCI-H446 cells and that HIF-1α is required in this process. The results also suggested a suppressive role of SOCS3 in Akt signaling, but not STAT3 signaling to block HIF-1α expression and a previously unidentified regulatory mechanism for Akt function. In conclusion, the present study suggested that SOCS3 targets the Akt signaling pathway to inhibit HIF-1α expression and affect the growth and angio-genesis of SCLC cells, and may therefore be considered as a potential novel therapeutic for the treatment of SCLC.

Transgelin overexpression in lung adenocarcinoma is associated with tumor progression

Hypoxia is a common feature of solid tumors and is associated with an increased likelihood of local recurrence and distant metastasis. Transgelin (TAGLN) is an actin cross-linking/polymerization protein that belongs to the family of actin-associated proteins, and there is evidence that TAGLN may be involved in the migration of epithelial cells by interacting with actin or promoting podosome formation. Cell migration is a key step of cancer metastatis. Thus, the aim of this study was to investigate the potential link between TAGLN protein levels and hypoxia in lung adenocarcinoma cells and to explore the possible functions and expression patterns of TAGLN in lung adenocarcinoma. We first examined the effects of altered TAGLN expression on cell migration under both normoxic and hypoxic conditions. Immunohistochemical (IHC) staining was also performed to examine TAGLN protein expression patterns in lung adenocarcinoma samples. Our results revealed that TAGLN was upregulated in the hypoxic lung adenocarcinoma cells. The inhibition of TAGLN expression in the cells using small interfering RNA (siRNA) led to a decreased migration ability. TAGLN was significantly overexpressed in the lung adenocarcinoma tissues compared to the adjacent tumor-free tissues. A high TAGLN expression correlated with an advanced TNM stage, lymph node metastasis and greater differentiation. TAGLN was upregulated in the human lung adenocarcinoma cell lines under hypoxic conditions, which contributed to the migration ability of the cells. Thus, our data suggest that TAGLN may be a viable therapeutic target and a potential biomarker for predicting the prognosis of patients with lung adenocarcinoma.

The HIF1A functional genetic polymorphism at locus +1772 associates with progression to metastatic prostate cancer and refractoriness to hormonal castration

The hypoxia inducible factor 1 alpha (HIF1a) is a key regulator of tumour cell response to hypoxia, orchestrating mechanisms known to be involved in cancer aggressiveness and metastatic behaviour. In this study we sought to evaluate the association of a functional genetic polymorphism in HIF1A with overall and metastatic prostate cancer (PCa) risk and with response to androgen deprivation therapy (ADT). The HIF1A +1772 C>T (rs11549465) polymorphism was genotyped, using DNA isolated from peripheral blood, in 1490 male subjects (754 with prostate cancer and 736 controls cancer-free) through Real-Time PCR. A nested group of cancer patients who were eligible for androgen deprivation therapy was followed up. Univariate and multivariate models were used to analyse the response to hormonal treatment and the risk for developing distant metastasis. Age-adjusted odds ratios were calculated to evaluate prostate cancer risk. Our results showed that patients under ADT carrying the HIF1A +1772 T-allele have increased risk for developing distant metastasis (OR, 2.0; 95%CI, 1.1-3.9) and an independent 6-fold increased risk for resistance to ADT after multivariate analysis (OR, 6.0; 95%CI, 2.2-16.8). This polymorphism was not associated with increased risk for being diagnosed with prostate cancer (OR, 0.9; 95%CI, 0.7-1.2). The HIF1A +1772 genetic polymorphism predicts a more aggressive prostate cancer behaviour, supporting the involvement of HIF1a in prostate cancer biological progression and ADT resistance. Molecular profiles using hypoxia markers may help predict clinically relevant prostate cancer and response to ADT.

Searching for Hif1-α interacting proteins in renal cell carcinoma

INTRODUCTION

Kidney tumours are frequently characterised by hypoxic conditions due to a local imbalance between oxygen (O2) supply and consumption. Hif1-α regulates angiogenesis, tumour growth, tumour progression, metastatic spread, and glucose metabolism by acting as a transcription factor for relevant genes. Here, we describe an immunohistochemical study of Hif1-α, a comprehensive computational study of Hif1-α interacting proteins (HIPs), an analysis correlating expression levels of Hif1-α with upstream and downstream proteins, and an analysis of the utility of Hif1-α for prognosis in a cohort of patients with renal cell carcinoma.

MATERIALS AND METHODS

The patient cohort included 80 patients. For immunohistochemistry evaluation, tissue microarrays were constructed. The IntAct, MINT, and BOND databases were used for the HIP approach. The Kruskal-Wallis test was used for comparing protein expression with pathology measurements. Correlation was expressed as the Pearson coefficient.

RESULTS

Hif1-α expression correlates significantly with the "clear" histological subtype of renal cell carcinoma (p < 0.01). The samples with the worst prognoses related to the pathological variables analysed showed the highest levels of Hif1-α expression. Significant correlations were found with Bcl-2, CAIX, C-kit, EGFR, TGF-β, proteins of the VEGF family, proteins related to differentiation (such as Notch1 and Notch3) and certain metabolic enzymes. Bioinformatic analysis suggested 45 evidence-based HIPs and 4 complexes involving protein Hif1-α.

CONCLUSIONS

This work summarises the multifaceted role of Hif1-α in the pathology of renal cell carcinomas, and it identifies HIPs that could help provide mechanistic explanations for the different behaviours seen in tumours.

Association of hypoxia inducible factor-1α polymorphisms with susceptibility to non-small-cell lung cancer

Hypoxia-inducible factor-1α (HIF-1α) is a key regulator of cellular response to hypoxia and has been suggested to play an important role in tumorigenesis and metastasis. The aim of this study was to investigate the role of HIF-1α-1772 C/T (P582S) and -1790 G/A (A588T) polymorphisms in the susceptibility to and severity of non-small-cell lung cancer (NSCLC). Using a case-control study design and polymerase chain reaction-restriction fragment-length polymorphism (PCR-RFLP) analysis, the allele frequencies and genotype distributions of each single nucleotide polymorphism in 285 NSCLC cases and 300 gender-matched controls were compared. The distribution of the genotype frequencies of HIF-1α-1772 C/T and -1790 G/A were significantly different between the NSCLC and the controls. Logistic regression analysis revealed that higher odds ratios (ORs) for lung cancer were observed for individuals with HIF-1α-1772 T/T genotype against CC/CT genotypes (an OR of 4.04, 95% confidence interval [CI] = 2.02-8.08, P = 0.0001), and HIF-1α-1790 A/A genotype against GG/GA genotypes (an OR of 4.42, 95% CI 2.22-8.78, P < 0.0001). There were no relationship between HIF-1α-1772 C/T or -1790 G/A allele distribution and disease severity of NSCLC (P > 0.05). However, those patients carrying a HIF-1α-1772 T/T genotype or a HIF-1α-1790 A/A had a tendency toward inferior prognosis compared with other patients.