A Novel Nomogram Combining Alternative Splicing Events and Clinical Factors for Prognosis Prediction in Head and Neck Squamous Cell Carcinoma.

Due to limitations of sensitive biomarkers, the clinical prognosis of patients with head and neck squamous cell carcinoma (HNSCC) remains poor. Alternative splicing (AS) is the basis of both transcriptome and proteome richness, so more and more evidence indicates an important relationship between AS and tumor progression. The aim of this study was to offer a comprehensive analysis on AS events and then investigate its potentials as a new biomarker for patients with squamous cell carcinoma of the head and neck. In this study, univariate assays were conducted to examine the prognosis-associated AS events, and we screened 4068 survival-related AS events in 2573 genes. Then, the AS events related to survival were further determined and analyzed using LASSO regression and multivariate assays, and an eleven-AS signature was developed. Kaplan-Meier assays indicated patients with high-risk scores exhibited a shorter OS than those with low-risk scores. Multivariate assays further demonstrated that the signature's risk score was independent of HNSCC survivals. Meanwhile, we analyzed the clinical association of AS-based prognostic signature in HNSCC patients and observed that tumor specimens with advanced stages and grades exhibited a high risk score. In addition, the results of survival nomogram revealed that predicted outcomes and actual outcomes were highly consistent. Overall, our group showed an eleven-AS signature of HNSCC, which could be regarded as a separate prognostic factor.

Genome sequencing and transcriptome analyses provide insights into the origin and domestication of water caltrop (Trapa spp., Lythraceae).

Humans have domesticated diverse species from across the plant kingdom; however, our current understanding of plant domestication is largely founded on major cereal crops. Here, we examine the evolutionary processes and genetic basis underlying the domestication of water caltrop (Trapa spp., Lythraceae), a traditional, yet presently underutilized non-cereal crop that sustained early Chinese agriculturalists. We generated a chromosome-level genome assembly of tetraploid T. natans, and then divided the allotetraploid genome into two subgenomes. Based on resequencing data from 57 accessions, representing cultivated diploid T. natans, wild T. natans (2x and 4x) and diploid T. incisa, we showed that water caltrop was likely first domesticated in the Yangtze River Valley as early as 6300 yr BP, and experienced a second improvement c. 800 years ago. We also provided strong support for an allotetraploid origin of T. natans within the past 230 000-310 000 years. By integrating selective sweep and transcriptome profiling analyses, we identified a number of genes potentially selected and/or differentially expressed during domestication, some of which likely contributed not only to larger fruit sizes but also to a more vigorous root system, facilitating nutrient uptake, environmental stress response and underwater photosynthesis. Our results shed light on the evolutionary and domestication history of water caltrop, one of the earliest domesticated crops in China. This study has implications for genomic-assisted breeding of this presently underutilized aquatic plant, and improves our general understanding of plant domestication.

Design and synthesis of 7-O-1,2,3-triazole hesperetin derivatives to relieve inflammation of acute liver injury in mice.

Based on the previous research results of our research group, to further improve the anti-inflammatory activity of hesperetin, we substituted triazole at the 7-OH branch of hesperetin. We also evaluated the anti-inflammatory activity of 39 new hesperetin derivatives. All compounds showed inhibitory effects on nitric oxide (NO) and inflammatory factors in lipopolysaccharide-induced RAW264.7 cells. Compound d5 showed a strong inhibitory effect on NO (half maximal inhibitory concentration = 2.34 ± 0.7 µM) and tumor necrosis factor-α, interleukin (IL)-1ß, and (IL-6). Structure-activity relationships indicate that 7-O-triazole is buried in a medium-sized hydrophobic cavity that binds to the receptor. Compound d5 can also reduce the reactive oxygen species production and significantly inhibit the expression of inducible NO synthase and cyclooxygenase-2 through the nuclear factor-κB signaling pathway. In vivo results indicate that d5 can reduce liver inflammation in mice with acute liver injury (ALI) induced by CCI4. In conclusion, d5 may be a candidate drug for treating inflammation associated with ALI.

Tumor-suppressor Fbxw7 targets SIK2 for degradation to interfere with TORC2-AKT signaling in pancreatic cancer.

The tumor suppressor F-box/WD repeat-containing protein 7 (Fbxw7) is a substrate-recognition subunit of a ubiquitin ligase complex. We have previously proposed that Fbxw7 inhibited pancreatic cancer cell proliferation and invasion by targeting ß-catenin. To identify other targets of Fbxw7 involved in pancreatic carcinogenesis, we screened the human protein database for Fbxw7 target candidates using the conserved Fbxw7-recognizing sequences. Twenty-three candidates are identified, including five known Fbxw7 targets and two cancer-related genes (salt inducible kinase 2 [SIK2] and ZMIZ1). We identified SIK2 as an Fbxw7 target for degradation by binding to the "TPPPS" motif of SIK2 in pancreatic cancer cells. We also demonstrated that SIK2 promoted proliferation and mitotic progression of pancreatic cancer cells. Moreover, endogenous Fbxw7 downregulates SIK2 protein level for controlling cell cycle progression, possibly by interfering the SIK2/TORC2/AKT signaling pathway to modulate p21 expression. Collectively, these data demonstrate that Fbxw7 targets the cell cycle controller, SIK2, for degradation, thereby leading to the disruption of downstream TORC2/AKT signaling to inhibit pancreatic cancer cell proliferation and cell cycle progression.

Application of Paclitaxel-loaded EGFR Peptide-conjugated Magnetic Polymeric Liposomes for Liver Cancer Therapy.

Developing the methodologies that allow for safe and effective delivery of therapeutic drugs to target sites is a very important research area in cancer therapy. In this study, polyethylene glycol (PEG)-coated magnetic polymeric liposome (MPL) nanoparticles (NPs) assembled from octadecyl quaternized carboxymethyl chitosan (OQC), PEGylated OQC, cholesterol, and magnetic NPs, and functionalized with epithelial growth factor receptor (EGFR) peptide, were successfully prepared for in-vivo liver targeting. The two-step liver targeting strategy, based on both magnetic force and EGFR peptide conjugation, was evaluated in a subcutaneous hepatocellular carcinoma model of nude mouse. The results showed that EGFR-conjugated MPLs not only accumulated in the liver by magnetic force, but could also diffuse into tumor cells as a result of EGFR targeting. In addition, paclitaxel (PTX) was incorporated into small EGFR-conjugated MPLs (102.0±0.7 nm), resulting in spherical particles with high drug encapsulation efficiency (>90%). The use of the magnetic targeting for enhancing the transport of PTX-loaded EGFR-conjugated MPLs to the tumor site was further confirmed by detecting PTX levels. In conclusion, PTX-loaded EGFR-conjugated MPLs could potentially be used as an effective drug delivery system for targeted liver cancer therapy.

Reactive oxygen species-mediated cellular genotoxic stress is involved in 1-nitropyrene-induced trophoblast cycle arrest and fetal growth restriction.

1-nitropyrene (1-NP) is a key component of diesel exhaust-sourced fine particulate matter (PM2.5). Our recent study demonstrated that gestational 1-NP exposure caused placental proliferation inhibition and fetal intrauterine growth restriction (IUGR). This study aimed to investigate the role of genotoxic stress on 1-NP-induced placental proliferation inhibition and fetal IUGR. Human trophoblasts were exposed to 1-NP (10 µM). Growth index was reduced and PCNA was downregulated in 1-NP-exposed placental trophoblasts. More than 90% of 1-NP-exposed trophoblasts were arrested in either G0/G1 or G2/M phases. CDK1 and cyclin B, two G2/M cycle-related proteins, and CDK2, a G0/G1 cycle-related protein, were reduced in 1-NP-exposed trophoblasts. Phosphorylated Rb, a downstream molecule of CDK2, was inhibited in 1-NP-exposed trophoblasts. Moreover, DNA double-strand break was observed and γ-H2AX, another indicator of DNA double-strand break, was upregulated in 1-NP-exposed trophoblasts. Phosphorylated ATM, a key molecule of genotoxic stress, and its downstream molecule Chk2 were elevated. By contrast, Cdc25A, a downstream target of Chk2, was reduced in 1-NP-exposed trophoblasts. Phenyl-N-t-butylnitrone (PBN), a free radical scavenger, inhibited 1-NP-induced genotoxic stress and trophoblast cycle arrest. Animal experiment showed that N-acetylcysteine (NAC), an antioxidant, rescued 1-NP-induced placental proliferation inhibition and fetal IUGR in mice. These results provide evidence that reactive oxygen species (ROS)-mediated cellular genotoxic stress partially contributes to 1-NP-induced placental proliferation inhibition and fetal IUGR.

Calcitriol inhibits migration and invasion of renal cell carcinoma cells by suppressing Smad2/3-, STAT3- and ß-catenin-mediated epithelial-mesenchymal transition.

Low vitamin D status is associated with progression in patients with renal cell carcinoma (RCC). The present study found that vimentin, a mesenchymal marker, was accordingly upregulated, and E-cadherin, an epithelial marker, was downregulated in RCC patients with low vitamin D status. Thus, we investigated the effects of calcitriol or vitamin D3, an active form of vitamin D, on epithelial-mesenchymal transition (EMT) in RCC cells. RCC cells were treated by two models. In model 1, three RCC cell lines, ACHN, 786-O and CAKI-2, were incubated with either LPS (2.0 µg/mL) or transforming growth factor (TGF)-ß1 (10 ng/mL) in the presence or absence of calcitriol (200 nmol/L). In model 2, two RCC cell lines, ACHN and CAKI-2, were incubated with calcitriol (200 nmol/L) only. Calcitriol inhibited migration and invasion not only in TGF-ß1-stimulated but also in TGF-ß1-unstimulated RCC cells. Moreover, calcitriol suppressed E-cadherin downregulation and vimentin upregulation not only in TGF-ß1-stimulated but also in TGF-ß1-unstimulated ACHN and CAKI-2 cells. Calcitriol attenuated LPS-induced upregulation of MMP-2, MMP-7, MMP-9, MMP-26 and urokinase-type plasminogen activator (u-PA) in ACHN cells. In addition, calcitriol blocked TGF-ß1-induced nuclear translocation of ZEB1, Snail and Twist1 in ACHN and CAKI-2 cells. Mechanistically, calcitriol suppressed EMT through different signaling pathways: (i) calcitriol suppressed Smad2/3 phosphorylation by reinforcing physical interaction between vitamin D receptor (VDR) and Smad3 in TGF-ß1-stimulated RCC cells; (ii) calcitriol inhibited signal transducer and activator of transcription (STAT)3 activation in LPS-stimulated RCC cells; (iii) calcitriol inhibited ß-catenin/TCF-4 activation by promoting integration of VDR with ß-catenin in TGF-ß1-unstimulated RCC cells. Taken together, calcitriol inhibits migration and invasion of RCC cells partially by suppressing Smad2/3-, STAT3- and ß-catenin-mediated EMT.

The Vitamin D status is associated with serum C-reactive protein and adhesion molecules in patients with renal cell carcinoma.

Low vitamin D status is associated with an increased risk of renal cell carcinoma (RCC). This study investigated the association of vitamin D status with serum C-reactive protein (CRP) and adhesion molecules among RCC patients. Fifty newly diagnosed RCC patients and 100 age- and sex-matched controls were recruited. As expected, serum 25(OH)D level was lower in RCC patients than in controls. By contrast, serum levels of CRP, an inflammatory molecule, and ICAM, LAMA4 and EpCAM, three adhesion molecules, were higher in RCC patients than in controls. All RCC patients were divided into two groups: H-VitD (>20 ng/ml) or L-VitD (<20 ng/ml). Interestingly, the levels of serum CRP and all adhesion molecules were higher in RCC patients with L-VitD than those with H-VitD. Nuclear vitamin D receptor (VDR) was downregulated and nuclear factor kappa B (NF-κB) was activated in cancerous tissues. The in vitro experiments found that VitD3 suppressed NF-κB activation and adhesion molecules in RCC cells. Moreover, VitD3 suppressed NF-κB through reinforcing physical interaction between VDR and NF-κB p65 subunit in RCC cells. These results provide a mechanistic explanation for the association among low vitamin D status, local inflammation and increased expression of adhesion molecules among RCC patients.

Cumulative Score Based on Preoperative Fibrinogen and Pre-albumin Could Predict Long-term Survival for Patients with Resectable Gastric Cancer.

Background: To investigate the prognostic significance of the cumulative score based on preoperative fibrinogen and pre-albumin (FP score) in patients with gastric cancer after radical gastrectomy. Methods: Baseline characteristics, preoperative fibrinogen and pre-albumin levels were retrospectively reviewed in patients who underwent radical gastrectomy. The optimal cut-off values for fibrinogen and pre-albumin were defined as 4.0 g/L and 230.0 mg/L, respectively. Patients with elevated fibrinogen (≥ 4.0 g/L) and decreased pre-albumin (< 230.0 mg/L) levels were allocated an FP score of 2, those with only one of these two abnormalities were assigned a score of 1, and those with neither of the two abnormalities were allocated a score of 0. The prognostic value was examined by univariate and multivariate regression analyses. Results: The preoperative FP score was significantly correlated with age, tumor size, fibrinogen level, pre-albumin level and white blood cell count. No significant differences based on sex, tumor location, degree of differentiation, depth of invasion, lymph node status, tumor-node-metastasis (TNM) stage or adjuvant chemotherapy were identified between the groups. In addition, univariate survival analysis revealed that a high preoperative FP score was significantly associated with unfavorable disease-free survival (DFS) [hazard ratio (HR), 1.482; 95% confidence interval (CI), 1.222-1.796; P < 0.001] and overall survival (OS) (HR, 1.623; 95% CI, 1.315-2.002; P < 0.001). Moreover, after adjusting for other factors, a high preoperative FP score remained an independent predictor for impaired DFS (HR, 1.434; 95% CI, 1.177-1.747; P < 0.001) and OS (HR, 1.413; 95% CI, 1.136-1.758; P = 0.002) in multivariate Cox regression analysis. Conclusions: The preoperative FP score significantly predicts long-term survival for gastric cancer patients who have undergone radical gastrectomy.

Nomograms for predicting survival in patients with metastatic gastric adenocarcinoma who undergo palliative gastrectomy.

BACKGROUND: Recently, evidence has emerged that palliative gastrectomy in patients with stage IV gastric cancer may offer some survival benefits. However, the decision whether to perform primary tumor surgery remains challenging for surgeons, and investigations into models that are predictive of prognosis are scarce. Current study aimed to develop and validate prognostic nomograms for patients with metastatic gastric adenocarcinoma treated with palliative gastrectomy. METHODS: The development dataset comprised 1186 patients from the Surveillance, Epidemiology, and End Results Program who were diagnosed with metastatic gastric adenocarcinoma in 2004-2011, while the validation dataset included 407 patients diagnosed in 2012-2015. Variables were incorporated into a Cox proportional hazards model to identify independent risk factors for survival. Both pre- and postoperative nomograms for predicting 1- or 2-year survival probabilities were constructed using the development dataset. The concordance index (c-index) and calibration curves were plotted to determine the accuracy of the nomogram models. Finally, the cut-off value of the calculated total scores based on preoperative nomograms was set and validated by comparing survival with contemporary cases without primary tumor surgery. RESULTS: Age, tumor size, location, grade, T stage, N stage, metastatic site, scope of gastrectomy, number of examined lymph node(s), chemotherapy and radiotherapy were risk factors of survival and were included as variables in the postoperative nomogram; the c-indices of the development and validation datasets were 0.701 (95% confidence interval [CI]: 0.693-0.710) and 0.699 (95% CI: 0.682-0.716), respectively. The preoperative nomogram incorporated age, tumor size, location, grade, depth of invasion, regional lymph node(s) status, and metastatic site. The c-indices for the internal (bootstrap) and external validation sets were 0.629 (95% CI: 0.620-0.639) and 0.607 (95% CI: 0.588-0.626), respectively. Based on the preoperative nomogram, patients with preoperative total score > 28 showed no survival benefit with gastrectomy compared to no primary tumor surgery. CONCLUSIONS: Our survival nomograms for patients with metastatic gastric adenocarcinoma undergoing palliative gastrectomy can assist surgeons in treatment decision-making and prognostication.

The correlation between low vitamin D status and renal interleukin-6/STAT3 hyper-activation in patients with clear cell renal cell carcinoma.

Low vitamin D status has been associated with increased risks of renal cell carcinoma (RCC). This study aimed to analyze the link between low vitamin D status and interleukin (IL)-6/STAT3 hyper-activation in clear cell RCC (ccRCC) patients. Forty-three newly diagnosed ccRCC patients and 86 age- and sex-matched controls were recruited. The association between low vitamin D status and IL-6/STAT3 hyper-activation was analyzed. Proliferation makersand STAT3 signal were evaluated. As expected, serum IL-6 level was higher in ccRCC patients than in controls. Moreover, serum IL-6 level was reversely correlated with serum 25(OH)D in ccRCC patients but not in controls. In addition, STAT3 signaling was hyper-activated in cancerous tissue. CcRCC patients were divided into three groups according to serum 25(OH)D level: vitamin D sufficiency (VitD-S, ≥30 ng/ml), vitamin D insufficiency (VitD-I, ≥20 and <30 ng/ml) or vitamin D deficiency (VitD-D, <20 ng/ml). Serum IL-6 was higher in ccRCC patients with VitD-D than those with VitD-S/VitD-I. Cancerous pSTAT3 level was higher in ccRCC patients with VitD-D than those with VitD-S/VitD-I. The number of pSTAT3+ nuclei in cancerous tissue was more in ccRCC patients with VitD-D than those with VitD-S/VitD-I. The expressions of cancerous PCNA, cyclin D1 and Ki-67, three markers of proliferation, were higher in ccRCC patients with VitD-D than those with VitD-S/VitD-I. The in vitro experiments showed that active vitamin D3 inhibited LPS-induced STAT3 phosphorylation in ACHN cells. Our results provide evidence that low vitamin D status is correlated with hyper-activation of cancerous IL-6/STAT3 and proliferation in ccRCC patients.

Author Correction: Craniometrics Reveal "Two Layers" of Prehistoric Human Dispersal in Eastern Eurasia.

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has not been fixed in the paper.

Craniometrics Reveal "Two Layers" of Prehistoric Human Dispersal in Eastern Eurasia.

This cranio-morphometric study emphasizes a "two-layer model" for eastern Eurasian anatomically modern human (AMH) populations, based on large datasets of 89 population samples including findings directly from ancient archaeological contexts. Results suggest that an initial "first layer" of AMH had related closely to ancestral Andaman, Australian, Papuan, and Jomon groups who likely entered this region via the Southeast Asian landmass, prior to 65-50 kya. A later "second layer" shared strong cranial affinities with Siberians, implying a Northeast Asian source, evidenced by 9 kya in central China and then followed by expansions of descendant groups into Southeast Asia after 4 kya. These two populations shared limited initial exchange, and the second layer grew at a faster rate and in greater numbers, linked with contexts of farming that may have supported increased population densities. Clear dichotomization between the two layers implies a temporally deep divergence of distinct migration routes for AMH through both southern and northern Eurasia.

PKM2, a potential target for regulating cancer.

Aberrated glucose metabolism is a key future of cancer cells. Unlike normal cells, tumor cells favor glycolysis even in the presence of sufficient oxygen. Pyruvate kinase (PK), a key glucose metabolic enzyme, converts phosphoenolpyruvate (PEP) to pyruvate by transferring the high-energy phosphate group to adenosine diphosphate (ADP) to produce adenosine triphosphate (ATP). Pyruvate kinase M2 (PKM2), one of the four isozyme of PK, which universally expressed in rapidly proliferating cells such as embryonic cells and cancer cells. Recent years, more and more research suggested PKM2 plays a crucial role in cancer progression through both metabolic and non-metabolic pathways. On the one hand, the middle product of glycolysis, such as amino acids, nucleotides, lipids is necessary to rapid growth of cancer cells. On the other hand, PKM2 supports tumor growth through regulating the expression of gene that involved in cell proliferation, migration and apoptosis. In this article, we review the recent advances to further understand the regulation and function of PKM2 in tumorigenesis. Given its multiple effects on cancer, PKM2 may be a potential target for cancer diagnosis and treatment.

Use of erlotinib and thalidomide in advanced NSCLC patients with acquired resistance to erlotinib: A pilot study.

Evidences suggested that combined blockade of the VEGF and EGFR pathways can improve the treatment efficacy of non-small-cell lung cancer (NSCLC). In our previously clinical practice, we observed that thalidomide, a potent VEGF inhibitor, can significantly decrease the tumor size of one EGFR-TKI resistance patient with lung cancer cachexia. In this pilot study, we tried to assess the efficacy and toxicity of the combination therapy of erlotinib and thalidomide in advanced NSCLC patients with acquired resistance to erlotinib. In all, 52 NSCLC patients with drug resistance to erlotinib were recruited and treated with this combination therapy. After treatment, 4 patients presented with partial remission (PR), 16 with stable disease (SD) and 32 with progressive disease (PD). The objective response rate (ORR) and disease control rate (DCR) was 7.7% and 38.5%, respectively. In this study, we firstly confirmed that thalidomide can reversion of erlotinib-acquired resistance with a 7 weeks median progression-free survival (PFS); besides, this combination therapy shows acceptable drug tolerance; the most common drug related adverse events were astriction, numbness and sleeve-like feeling in the limbs, no thrombosis occurred in any patient. Those evidences indicate that thalidomide may be a useful candidate for reversion of erlotinib-acquired resistance.

Urinary 6-sulfatoxymelatonin level and breast cancer risk: systematic review and meta-analysis.

6-Sulfatoxymelatonin (aMT6s) is the main metabolite of melatonin in urine, and is a reliable surrogate biomarker reflecting the blood melatonin concentration. This meta-analysis assessed the association between urinary aMT6s level and BC incidence. The electronic databases PubMed, EMBASE, Cochrane Library, and Web of Science were searched. Risk ratios (RRs) were adopted to estimate the relative BC incidence. A total of 7 prospective case-control publications were included, and 6 of them were distinct studies. Pooled analysis of data from the 6 studies involving 1824 women with incident BC and 3954 matched control participants with no overlapping of subjects among studies indicated no significant association between the highest levels of urinary aMT6s and the incidence of BC (RR = 0.97, 95% CI, 0.88-1.08, P = 0.56). Negative associations were observed in postmenopausal women (RR = 0.88, 95% CI, 0.75-1.02, P = 0.10), estrogen receptor positive BC (RR = 0.83, 95% CI, 0.64-1.07, P = 0.15), and studies using 12-hour overnight urine (RR = 0.81, 95% CI, 0.61-1.07, P = 0.13), all with borderline significances. Lag time or invasive degree did not interfere with the results. There was no evident publication bias detected by the Egger's test and the funnel plot. Conclusively, the current evidence did not support a significant association between urinary aMT6s level and BC risk.

Efficacy and safety of recombinant human lymphotoxin-α derivative with cisplatin and fluorouracil in patients with metastatic esophageal squamous cell carcinoma: A randomized, multicenter, open-label, controlled, phase 2b trial.

BACKGROUND: Recombinant human lymphotoxin-α derivative (rhLTα-Da) is a lymphotoxin-α derivative that is missing 27 N-terminal amino acid residues. Previous studies indicated a benefit from the addition of rhLTα-Da to cisplatin-based treatment in patients with metastatic esophageal squamous cell carcinoma. The current study was conducted to evaluate the efficacy and safety of rhLTα-Da plus cisplatin and fluorouracil (PF) in patients with mESCC. METHODS: Patients from 15 centers in China were randomly assigned (1:1:1) to 3 arms (arm A, PF plus 10 µg/m2 daily rhLTα-Da; arm B, PF plus 20 µg/m2 daily rhLTα-Da; arm C, PF alone). The primary endpoints included progression-free survival (PFS) and the confirmed overall response rate (ORR). An exploratory analysis was performed to evaluate the role of serum tumor necrosis factor receptor II (TNFR II) in predicting the efficacy of rhLTα-Da. RESULTS: Between September 2010 and May 2013, 150 patients were enrolled. No significant differences in either PFS or ORR were observed between the 3 arms. However, in a small subset of patients who had low serum TNFR II levels, the median PFS was significantly longer for those in arm B than for these in other 2 arms (7.2 months [95% confidence interval, 5.1-8.6 months] for arm B vs 3.5 months [95% confidence interval, 1.7-5.5 months] for arm A [P = .022] and 4.0 months [95% confidence interval, 3.2-6.3 months] for arm C [P = .027]). The addition of rhLTα-Da significantly increased the incidence of chills (P < .001). CONCLUSIONS: rhLTα-Da combined with the PF regimen failed to improve PFS and ORR in patients with mESCC, except in a small subset that had low serum TNFR II concentrations. Cancer 2017;123:3986-94. © 2017 American Cancer Society.

Melatonin, a novel selective ATF-6 inhibitor, induces human hepatoma cell apoptosis through COX-2 downregulation.

AIM: To clarify the mechanisms involved in the critical endoplasmic reticulum (ER) stress initiating unfolded protein response pathway modified by melatonin. METHODS: Hepatoma cells, HepG2, were cultured in vitro. Flow cytometry and TUNEL assay were used to measure HepG2 cell apoptosis. Western blotting and quantitative reverse transcription-polymerase chain reaction methods were used to determine the protein and messenger RNA levels of ER stress and apoptosis related genes' expression, respectively. Tissue microarray construction from patients was verified by immunohistochemical analysis. RESULTS: In the present study, we first identified that melatonin selectively blocked activating transcription factor 6 (ATF-6) and then inhibited cyclooxygenase-2 (COX-2) expression, leading to enhanced liver cancer cell apoptosis under ER stress condition. Dramatically increased CCAAT-enhancer-binding protein homologous protein level, suppressed COX-2 and decreased Bcl-2/Bax ratio by melatonin or ATF-6 siRNA contributed the enhanced HepG2 cell apoptosis under tunicamycin (an ER stress inducer) stimulation. In clinical hepatocellular carcinoma patients, the close relationship between ATF-6 and COX-2 was further confirmed. CONCLUSION: These findings indicate that melatonin as a novel selective ATF-6 inhibitor can sensitize human hepatoma cells to ER stress inducing apoptosis.

RICTOR expression in esophageal squamous cell carcinoma and its clinical significance.

Esophageal cancer is one of the most common malignant tumors in the world, and its incidence is the eighth highest; meanwhile, its fatality rate is the sixth highest. The PI3K/Akt/mTOR signaling pathway plays a required role in human cancer, including cell survival, metabolism and migration. As a kind of important scaffold protein in mTORC2, RICTOR has showed over-expression in several malignancies like melanoma and endometrial cancer. In this research, we selected 201 cases of paraffin specimens from patients diagnosed as esophageal squamous cell carcinoma after surgical treatment and then estimated the RICTOR expression in each esophageal squamous cell carcinoma tissue by using the immunohistochemical streptavidin-peroxidase technique. Then, we analyzed the association among the clinicopathological parameters, the prognosis and the expression of RICTOR. Eventually, we found that the percentage of RICTOR-positive expression in 201 ESCC samples is 70.6% (142/201) and the figure for RICTOR-negative or RICTOR-doubtful-positive expression is 29.4% (59/201). RICTOR expression positively correlated with ESCC patients' AJCC stage (P = 0.011) and showed an opposite trend with survival (P = 0.007). Based on univariate and multivariate Cox proportional hazards regression analysis, RICTOR-positive expression, AJCC staging III or IV and nodal metastasis are prognostic factors and the former two are independent risk factors for ESCC. In conclusion, our study showed potential that targeting RICTOR may represent new effective inhibitors for treating ESCC.

Expression and Clinical Significance of Cytokeratin-19 and Thymidine Kinase-1 in Advanced Gastrointestinal Cancer.

BACKGROUND: As the clinical value of cytokeratin-19 (CK19) and thymidine kinase-1 (TK1) in advanced gastrointestinal cancer remains controversial, we investigated their expression and clinical significance in this disease. METHODS: A total of 171 advanced gastrointestinal cancer patients were prospectively enrolled in this study. The mRNA level of CK19 was detected using quantitative real-time reverse transcription-polymerase chain reaction (PCR) in all patients, along with a control group of fifty healthy individuals. Furthermore, detection of TK1 protein was carried out in 96 patients using a chemiluminescence dot blot assay. The primary endpoint was overall survival (OS) time. RESULTS: Positive CK19 mRNA expression was detected in 74 (43.3%) of the 171 patients and positive TK1 expression was detected in 66 (68.8%) of the 96 patients. Furthermore, of the 96 patients, 36 (37.5%) were positive for both TK1 protein and CK19 mRNA, 30 (31.3%) were negative for TK1 protein, and 15 (15.6%) were negative for TK1 protein and positive for CK19 mRNA. The results indicated that patients who were positive for CK19 mRNA expression had significantly shorter OS times than those who were negative for it (median OS 7.7 vs. 9.7 months, respectively; P = 0.02). Moreover, patients who were positive for CK19 mRNA and TK1 protein expression had shorter OS times (median OS 6.1 months) than those who were positive for CK19 mRNA and negative for TK1 protein expression (median OS 9.1 months; P = 0.028). Positive CK19 mRNA expression was significantly associated with shorter OS in the univariate analysis (P = 0.027). Based on a multivariate Cox regression analysis, CK19 mRNA together with TK1 protein expression (P = 0.024) was an independent predictor for OS in gastrointestinal cancer patients. CONCLUSIONS: Our results suggest that positive expression of CK19 mRNA and TK1 protein is closely correlated with poor prognosis in advanced gastrointestinal cancer. Furthermore, both CK19 and TK1 are possible gastrointestinal cancer biomarkers.