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Metabolic reprogramming plays a critical role in tumorigenesis and tumor progression. The metabolism and the proliferation of tumors are regulated by both intrinsic factors within the tumor and the availability of metabolites in the tumor microenvironment (TME). The metabolic niche within the TME is primarily orchestrated at 3 levels: 1) the regulation of tumor metabolism by factors intrinsic to the tumors, 2) the interaction between tumor cells and T cells, macrophages, and stromal cells, and 3) the metabolic heterogeneity of tumor cells within the tissue space. Herein, we provided a concise overview of the various metabolic regulatory modes observed in tumor cells. Additionally, we extensively analyzed the interaction between tumor cells and other cells within the TME, as well as the metabolic characteristics and functions of different types of cells. Ultimately, this review provides a theoretical basis and novel insights for the precision treatment of tumors.

Multi-biological functions of intermedin in diseases.

Intermedin (IMD) is a member of the calcitonin gene-related peptide (CGRP)/calcitonin (CT) superfamily, and it is expressed extensively throughout the body. The typical receptors for IMD are complexes composed of calcitonin receptor-like receptor (CLR) and receptor activity-modifying protein (RAMP), which leads to a biased activation towards Gαs. As a diagnostic and prognostic biomarker, IMD regulates the initiation and metastasis of multiple tumors. Additionally, IMD functions as a proangiogenic factor that can restrain excessive vascular budding and facilitate the expansion of blood vessel lumen, ultimately resulting in the fusion of blood vessels. IMD has protective roles in various diseases, including ischemia-reperfusion injury, metabolic disease, cardiovascular diseases and inflammatory diseases. This review systematically elucidates IMD's expression, structure, related receptors and signal pathway, as well as its comprehensive functions in the context of acute kidney injury, obesity, diabetes, heart failure and sepsis. However, the precise formation process of IMD short peptides in vivo and their downstream signaling pathway have not been fully elucidated yet. Further in-depth studies are need to translate IMD research into clinical applications.

A novel prognostic signature contributes to precision treatment in colon adenocarcinoma with KRAS mutation.

BACKGROUND: Approximately 40% of colon cancer harbor Kirsten rat sarcoma viral oncogene ( KRAS ) mutations, but the prognostic value of KRAS mutations in colon cancer is still controversial. METHODS: We enrolled 412 colon adenocarcinoma (COAD) patients with KRAS mutations, 644 COAD patients with KRAS wild-type and 357 COAD patients lacking information on KRAS status from five independent cohorts. A random forest model was developed to estimate the KRAS status. The prognostic signature was established using least absolute shrinkage and selection operator-Cox regression and evaluated by Kaplan-Meier survival analysis, multivariate-Cox analysis, receiver operating characteristic curve and nomogram. The expression data of KRAS -mutant COAD cell lines from the Cancer Cell Line Encyclopedia database and the corresponding drug sensitivity data from the Genomics of Drug Sensitivity in Cancer database were used for potential target and agent exploration. RESULTS: We established a 36-gene prognostic signature classifying the KRAS -mutant COAD as high and low risk. High risk patients had inferior prognoses compared to those with low risk, while the signature failed to distinguish the prognosis of COAD with KRAS wild-type. The risk score was the independent prognostic factor for KRAS -mutant COAD and we further fabricated the nomograms with good predictive efficiency. Moreover, we suggested FMNL1 as a potential drug target and three drugs as potential therapeutic agents for KRAS -mutant COAD with high risk. CONCLUSION: We established a precise 36-gene prognostic signature with great performance in prognosis prediction of KRAS -mutant COAD providing a new strategy for personalized prognosis management and precision treatment for KRAS -mutant COAD.

Safety and efficacy of postoperative adjuvant therapy with atezolizumab and bevacizumab after radical resection of hepatocellular carcinoma.

BACKGROUND: The effects of postoperative adjuvant therapy for high-risk recurrent hepatocellular carcinoma (HCC) in immunotherapy are still under investigation. This study evaluated the preventive effects and safety of postoperative adjuvant therapy, including atezolizumab, and bevacizumab, against the early recurrence of HCC with high-risk factors. METHODS: The complete data of HCC patients who underwent radical hepatectomy with or without postoperative adjuvant therapy after two-year follow-up were analyzed retrospectively. The patients were divided into high-risk or low-risk groups based on HCC pathological characteristics. High-risk recurrence patients were divided into postoperative adjuvant treatment and control groups. Due to the difference in approaches in postoperative adjuvant therapies, they were divided into transarterial chemoembolization (TACE), atezolizumab, and bevacizumab (T + A), and combination (TACE+T + A) groups. The two-year recurrence-free survival rate (RFS), overall survival rate (OS), and associated factors were analyzed. RESULTS: The RFS in the high-risk group was significantly lower than that in the low-risk group (P = 0.0029), and the two-year RFS in the postoperative adjuvant treatment group was significantly higher than that in the control group (P = 0.040). No severe complications were observed in those who received atezolizumab and bevacizumab or other therapy. CONCLUSION: Postoperative adjuvant therapy was related to two-year RFS. TACE, T + A, and the combination of these two approaches were comparable in reducing the early recurrence of HCC without severe complications.

The Promoting Role of HK II in Tumor Development and the Research Progress of Its Inhibitors.

Increased glycolysis is a key characteristic of malignant cells that contributes to their high proliferation rates and ability to develop drug resistance. The glycolysis rate-limiting enzyme hexokinase II (HK II) is overexpressed in most tumor cells and significantly affects tumor development. This paper examines the structure of HK II and the specific biological factors that influence its role in tumor development, as well as the potential of HK II inhibitors in antitumor therapy. Furthermore, we identify and discuss the inhibitors of HK II that have been reported in the literature.

RAB27A promotes the proliferation and invasion of colorectal cancer cells.

Colorectal cancer (CRC) is one of the most commonly diagnosed cancer types worldwide. Despite significant advances in prevention and diagnosis, CRC is still one of the leading causes of cancer-related mortality globally. RAB27A, the member of RAB27 family of small GTPases, is the critical protein for intracellular secretion and has been reported to promote tumor progression. However, it is controversial for the role of RAB27A in CRC progression, so we explored the exact function of RAB27A in CRC development in this study. Based on the stable colon cancer cell lines of RAB27A knockdown and ectopic expression, we found that RAB27A knockdown inhibited proliferation and clone formation of SW480 colon cancer cells, whereas ectopic expression of RAB27A in RKO colon cancer cells facilitated cell proliferation and clone formation, indicating that RAB27A is critical for colon cancer cell growth. In addition, our data demonstrated that the migration and invasion of colon cancer cells were suppressed by RAB27A knockdown, but promoted by RAB27A ectopic expression. Therefore, RAB27A is identified as an onco-protein in mediating CRC development, which may be a valuable prognostic indicator and potential therapeutic target for CRC.

Ampelopsin Inhibits Cell Viability and Metastasis in Renal Cell Carcinoma by Negatively Regulating the PI3K/AKT Signaling Pathway.

BACKGROUND: Previous studies have shown that Ampelopsin has an inhibitory effect on human tumors. However, the effect of Ampelopsin on renal cell carcinoma (RCC) is rarely reported. Therefore, this study aims to explain the role of Ampelopsin in RCC. METHODS: Different concentrations of Ampelopsin (0, 10, 25, 50, and 100 µM) were used to treat 786-O cells. Cell viability was detected by MTT assay, colony formation assay, and flow cytometry assay. Transwell assay and Wound healing assay were used to detect cell migration and invasion. Western blot analysis was applied to detect protein expression. RESULTS: Ampelopsin inhibited cell proliferation and induced apoptosis in RCC. And Ampelopsin can inhibit cell migration and invasion in RCC. All these results changed in a dose-dependent manner. Ampelopsin (100 uM) had the strongest inhibitory effect on cell viability and metastasis. In addition, Ampelopsin negatively regulated the PI3K/AKT signaling pathway in RCC cells. Moreover, Ampelopsin was only cytotoxic to RCC cells. CONCLUSION: Ampelopsin inhibits cell viability and metastasis in RCC by negatively regulating the PI3K/AKT signaling pathway.

A two-transcript biomarker of host classifier genes for discrimination of bacterial from viral infection in acute febrile illness: a multicentre discovery and validation study.

BACKGROUND: Acute febrile illness is one of the main reasons for outpatient hospital visits worldwide. However, differential diagnosis between bacterial and viral causes is challenging and misdiagnosis can result in antimicrobial overuse and hinder prompt treatment. We aimed to build and validate a diagnostic model to discriminate bacterial from viral infection in acute febrile illness by evaluating the expression of potential classifier host genes. METHODS: In this multicentre discovery and validation study, we included patients aged 14-85 years with acute febrile illness (fever for ≤14 days, axillary temperature of ≥38°C, and confirmed bacterial infection, viral infection, or non-infectious inflammatory disease), and healthy control participants (no significant medical history and no fever within the past 90 days) from four hospitals in Shandong province, China. Patients from the first hospital were divided into the screening, discovery, and internal validation groups, and patients from the three other hospitals comprised the external validation group. We measured expression of candidate genes in peripheral blood by RT-PCR, and patients for whom a successful RT-PCT result was recorded were included in the next-step analysis. For patients from the first hospital, those enrolled during the early phase of the study were assigned to the screening group, which was used to identify the optimal transcripts (IFI44L and PI3) for discrimination between bacterial and viral infections by screening four candidate genes (FAM89A, IFI44L, PI3, and ITGB2) by RT-PCR. The remaining patients were then randomly assigned (1:1) to discovery and internal validation groups by time of admission and blood drawing via the equidistant random sampling method. A logistic regression model integrating the mRNA levels of IFI44L and PI3 was built by use of the discovery group, and the diagnostic performance of the model was evaluated in the internal and external validation groups using area under the receiver operating curve (AUC), sensitivity, and specificity. FINDINGS: Between March 1, 2018, and Aug 31, 2019, we assessed 1658 individuals for inclusion in the study. After exclusion of ineligible participants, 458 participants were enrolled (178 patients with acute febrile illness caused by bacterial infection, 212 with acute febrile illness caused by viral infection, 38 with non-infectious inflammatory diseases, and 30 healthy controls). The 390 patients with bacterial or viral infections were assigned to one of four groups: screening (n=64, 33 with bacterial infections and 31 with viral infections), discovery (n=124, 55 with bacterial infections and 69 with viral infections), internal validation (n=124, 55 with bacterial infections and 69 with viral infections), and external validation (n=78, 35 with bacterial infections and 43 with viral infections). Of the four candidate host genes (FAM89A, IFI44L, PI3, and ITGB2), IFI44L and PI3 showed the most discriminative expression pattern and were used to build the logistic regression model. We established the optimal cutoff of the bacterial infection likelihood score to be 0·547598. With the diagnostic result from the gold standard tests (culture and PCR) as the reference, the two-transcript classifier model had an AUC of 0·969 (95% CI 0·937-1·000), sensitivity of 0·891 (0·782-0·949), and specificity of 0·971 (0·900-0·992) to discriminate bacterial and viral infections in the internal validation group. The model showed similar results in the external validation group (AUC 0·986, 95% CI 0·968-1·000; sensitivity 0·857, 0·706-0·937; and specificity 0·954, 0·845-0·987). INTERPRETATION: IFI44L and PI3 transcripts, measured by RT-PCR, are robust classifiers to discriminate bacterial from viral infection in acute febrile illness. This two-transcript biomarker has the potential to be transformed into a commercial panel and applied universally. FUNDING: None.

UHRF1 Knockdown Attenuates Cell Growth, Migration, and Invasion in Cutaneous Squamous Cell Carcinoma.

Ubiquitin like with PHD and ring finger domains 1 (UHRF1) contributes to the progression of many cancers. Here, we firstly observed UHRF1 was elevated in cutaneous squamous cell carcinoma (cSCC) and related to the differentiation stages. Knockdown of UHRF1 in A431 and Scl-1 attenuated cell proliferation, migration, and invasion, leading to G2/M cell cycle arrest and apoptosis. Through a mouse xenograft model, we found UHRF1 deficiency ameliorated tumor growth. These results may be associated with destruction of multiple signal pathways. In summary, our results suggest UHRF1 is involved in the pathogenesis of cSCC and may be a therapeutic target.

Identification of characteristic heroin metabolites in urine based on data-mining technology and multivariate statistics analysis combined with a targeted verification approach for distinguishing heroin abusers.

A common phenomenon shows that ingestion of opium poppy shell-containing drugs can result in a "false-positive" urinalysis test result for mandatory or workplace heroin abuse screening. Owing to the short detection window (8 h in urine) of the characteristic heroin metabolite 6-monoacetylmorphine (6-MAM) confirmation or exclusion of heroin abusers still presents major challenges for toxicologists. In this work, we developed an ultra-performance liquid chromatography-time-of-flight mass spectrometry method (UPLC-TOF-MS) with online data acquisition and multiple post-data-mining technologies combined with a multivariate statistical and batch validation analysis workflow to assess the characteristic urine metabolites of heroin abusers. Based on the proposed methods, 28 characteristic metabolites were structurally identified, and their fragmentation patterns and metabolite pathways were also summarized. Correlation analysis was used to investigate the internal relationship and similarities among the identified metabolites, and seven representative metabolites were selected as "Target-metabolites". Multi-batch urine of samples of heroin abusers were certified based on the UPLC-MS/MS method for further validation of the practicability of using this method for routine analysis. Overall, the target-metabolites can be utilized as assistant "biomarkers" in workplace or mandatory drug screenings. This approach encourages further studies on the development of the "false-positive" identification system.

LncRNA SNHG16 Promotes the Progression of Laryngeal Squamous Cell Carcinoma by Mediating miR-877-5p/FOXP4 Axis.

OBJECTIVE: Laryngeal cancer is a common malignant tumor in the ENT, of which laryngeal squamous cell carcinoma (LSCC) accounts for more than 90% of laryngeal cancer. The purpose of this study is to investigate the regulatory mechanism of lncRNA SNHG16 in LSCC. MATERIALS AND METHODS: Real-time quantitative reverse transcription polymerase chain reaction (RT-qPCR) was used to measure mRNA expression. Cell Counting Kit (CCK-8), Transwell and luciferase reporter assays, flow cytometric analysis and Western blot analysis were used to investigate the function of lncRNA SNHG16 in LSCC. RESULTS: SNHG16 expression was increased in LSCC tissues and cells. The abnormal expression of SNHG16 was associated with clinical stage and lymph node metastasis in LSCC patients. In addition, knockdown of SNHG16 restrained cell proliferation, migration and invasion in LSCC. More importantly, SNHG16 acted as a competitive endogenous RNA in LSCC and regulated FOXP4 expression by making miR-877-5p sponge. Further, SNHG16 promoted LSCC progression by interacting with miR-877-5p and FOXP4. CONCLUSION: LncRNA SNHG16 promotes the progression of LSCC by sponging miR-877-5p and upregulating FOXP4.

CDC20 contributes to the development of human cutaneous squamous cell carcinoma through the Wnt/ß­catenin signaling pathway.

Cell division cycle 20 (CDC20) is a regulatory molecule and serves critical roles at multiple points of the cell cycle. Recent evidence indicates that CDC20 may serve an oncogenic role in a number of human cancer types. However, the role of CDC20 in primary cutaneous squamous cell carcinoma (cSCC) has not been studied, to the best of our knowledge. The aim of the present study was to investigate whether and how CDC20 is involved in the tumorigenesis of cSCC. The results revealed that CDC20 expression was significantly increased in cSCC tissues and cell lines, and its expression was associated with pathological differentiation. Downregulation of CDC20 inhibited cell proliferation, induced cell cycle arrest, promoted apoptosis and reduced migratory ability through inhibition of the Wnt/ß­catenin signaling pathway. Furthermore, all­trans­retinoic acid treatment significantly downregulated CDC20 expression in cSCC. The present results revealed that CDC20 may serve a crucial role in human cSCC, and suggested that CDC20 may be a novel biomarker for the prevention, diagnosis and treatment of cSCC.

TWEAK/Fn14 Interaction Confers Aggressive Properties to Cutaneous Squamous Cell Carcinoma.

Recent studies showed that TWEAK/Fn14 signaling participates in the progression of internal malignancies. However, its role in the biological properties of cutaneous squamous cell carcinoma (SCC) remains unclear. This study was designed to explore the effect of TWEAK/Fn14 activation on cutaneous SCC as well as the relevant mechanism. The expression of TWEAK and Fn14 was determined in tissue samples of patients with cutaneous SCC. Human primary keratinocytes and SCC cell lines were cultured in vitro, receiving stimulation of TWEAK. The xenografts of SCC were generated subcutaneously in BALB/c nude mice. The results showed that both TWEAK and Fn14 were highly expressed in human cutaneous SCC. Moreover, TWEAK/Fn14 activation promoted the proliferation, migration, and invasion of cultured SCC cells. Interestingly, TNFR2 was upregulated in cultured SCC cells, and the transfection of TNFR2 small interfering RNA abrogated the effect of TWEAK on these cells. Finally, the favorable effect of TWEAK/Fn14 signals was confirmed in BALB/c nude mice with SCC xenografts. In conclusion, TWEAK/Fn14 signals contribute to the progression of cutaneous SCC, possibly involving the TNF-α-independent TNFR2 signal transduction.

Prognostic analysis of hepatocellular carcinoma on the background of liver cirrhosis via contrast-enhanced ultrasound and pathology.

The aim of this study was to analyze the correlation between the quantitative parameters of contrast-enhancement ultrasound for primary hepatocellular carcinoma (HCC) and biological manifestations of tumor (Ki-67), and to explore the related risk factors of primary hepatocellular carcinoma, so as to provide the theoretical basis for the further study on contrast-enhancement ultrasound manifestations, clinical features and prognosis of HCC. The patients with HCC confirmed by operation or puncture were collected, and those with the background of liver cirrhosis and immunohistochemical staining for tumor sample sections were selected. H&E staining sections of pathological tissues of tumor samples were observed, whether there was any microvessel invasion (MVI) was recorded, the microvessel density (MVD) was counted and the recurrence situations after liver cancer operation was followed up. The change in size of tumor at arterial phase in contrast-enhancement ultrasound, enhancement mode and form at arterial phase, and whether there were tortuous vessels inside or not, and the enhancement intensity, extinction time and extinction intensity at portal phase were observed. The relationship between the parameters of contrast-enhancement ultrasound and Ki-67, AFP, MVD, MVI, tissue differentiation degree of tumor samples and recurrence was analyzed. Under the background of liver cirrhosis, there were significant differences in different enhancement modes and quantification parameters of contrast-enhancement ultrasound for HCC with different expression of Ki-67. Those with obvious tumor enlargement, inhomogeneous enhancement at arterial phase and irregular enhancement form at arterial phase after contrast-enhancement ultrasound had a high incidence of positive Ki-67 and a high early recurrence rate. The inhomogeneous enhancement at arterial phase might predict the proliferative activity and recurrence time of tumor cells; irregular enhancement form at arterial phase might indicate tumor MVI; and the low enhancement of tumor at portal phase may predict a lower degree of tissue differentiation, a higher tumor malignancy and poor prognosis. The incidence of positive Ki-67 under the background of liver cirrhosis is high, indicating poor prognosis. The enhancement mode and parameters of contrast-enhancement ultrasound for HCC may help evaluate the clinical biological manifestations of HCC and predict the postoperative recurrence of HCC.

miR-3117 regulates hepatocellular carcinoma cell proliferation by targeting PHLPPL.

Altered microRNA expression is associated with tumor proliferation, metastasis, and tumorigenesis. In this study, we studied the role of miR-3117 in hepatocellular carcinoma (HCC) cell proliferation and found that miR-3117 was upregulated in HCC tissues and cells. MTT assay, soft agar growth assay, BrdU assay, and cell cycle assay revealed that miR-3117 overexpression promoted HCC HepG2 cell proliferation and that knockdown of miR-3117 suppressed HepG2 proliferation. Mechanism analysis suggested PH domain and leucine-rich repeat protein phosphatase-like (PHLPPL) as the target of miR-3117. Luciferase reporter assay suggested that miR-3117 directly binds to the 3'UTR of PHLPPL. Double knockdown of miR-3117 and PHLPPL copied the phenotypes caused by miR-3117 overexpression, suggesting that miR-3117 contributes to the proliferation of HepG2 by targeting PHLPPL. Our study provided a target for HCC therapy.

Downregulation of Bmi-1 suppresses epithelial­mesenchymal transition in melanoma.

Epithelial-mesenchymal transition (EMT) contributes to the invasion and metastasis of numerous malignant cancers, including melanoma. A significant higher expression of B-lymphoma Moloney murine leukemia virus insertion region-1 (Bmi-1) has been reported in cell lines from metastatic melanoma compared to cell lines from primary melanoma. There are studies that show that knockdown of Bmi-1 could induce E-cadherin expression in melanoma cells. However, the role of Bmi-1 in mediating EMT-like changes in melanoma has not yet been fully studied. In the present study, knockdown of Bmi-1 by shRNA transduction decreased the invasion properties of the cultured human melanoma cells A375 by a Matrigel invasion assay, along with alterations in EMT-related markers E-cadherin, α-catenin, vimentin and N-cadherin. The aforementioned altered expression of EMT markers was verified in BALB/c-nude mouse xenografts. Furthermore, to explore the underlying regulatory mechanism of EMT, we detected the significant downregulation of p-Akt/p­NF-κB/MMP-2 and the upregulation of PTEN in Bmi-1-silenced A375 cells. The present study demonstrated that knockdown of Bmi-1 significantly inhibited the aggressive behavior of melanoma by reversing EMT-like changes via the PTEN/p-Akt/p­NF-κB/MMP-2 pathway.

Effect of siRNA on Wisp-1 gene expression, proliferation, migration and adhesion of mouse hepatocellular carcinoma cells.

OBJECTIVE: To study the inhibition effect of siRNA on the expression of Wisp-1 gene in Hca-F of mouse hepatocellular carcinoma cells strain and also its effect on the proliferation, migration and adhesion of hepatocellular carcinoma cells. METHODS: Three expression vectors of siRNA were constructed. Lipo2000 was employed to transfect Hca-F cells and Western blot was used to detect the inhibition effect of siRNA on the expression of Wisp-1 gene. Afterward, CCK8 was adopted to detect the effect of Wisp-1 siRNA on the proliferation of Hca-F cells; Annexin V-FITC/PI double staining flow cytometry was used to detect the effect of Wisp-1 siRNA on the apoptosis of Hca-F cells; Transwell was used to detect the effect of Wisp-1 siRNA on the migration of Hca-F cells. The in vitro cell adhesion kit was used to detect of Wisp-1 siRNA on the change in the components of extracellular matrix to which Hca-F cells adhered. Western blot was used to detect the activation of protein kinase B (AKT)/glycogen synthase kinase-3ß pathway and the expression of downstream target protein p53 and matrix metalloproteinases-2. RESULTS: The siRNA showed interference effect on the expression of Wisp-1 gene. Compared with the control group, after being transfected to cells, Wisp-1 siRNA could significantly inhibit the proliferation, migration and adhesion of Hca-F cells and also promote the cell apoptosis, which was related to the down-regulated phosphorylation of AKT and glycogen synthase kinase-3ß and the expression of p53 and matrix metalloproteinases-2 (P < 0.05). CONCLUSIONS: The inhibition of Wisp-1 expression can reduce the proliferation, migration and adhesion of mouse hepatocellular carcinoma cells, which is related to the AKT/glycogen synthase kinase-3ß pathway. Wisp-1 gene may be the potential target to cure the hepatocellular carcinoma.

[Effect of beryllium on the morphology and chemical elements of cell membrane of Porphyromonas gingivalis].

PURPOSE: To evaluate the effect of beryllium (Be²âº) on the morphology and chemical elements on cell membrane of Porphyromonas gingivalis (P. gingivalis), thus to explore the microbiologic mechanisms of periodontal diseases. METHODS: P. gingivalis was put into the culture with different Be²âº concentrations and anaerobically cultured for 24 hours. The morphologic change of P. gingivalis was observed under microscope and scanning electronic microscope (SEM), and chemical elements of cell membrane were observed by X-ray energy dispersion spectrum (EDS). The data was statistically analyzed with SPSS13.0 software package. RESULTS: The morphology of P.gingivalis altered obviously at the concentration greater than 2.5 mg/L, which was manifested by the sharpness of border and depression on the surface. With the increased concentration of beryllium, the Na and Ca peak descended on the surface of P. gingivalis. CONCLUSIONS: Beryllium can interfere with the morphology of P. gingivalis, and lead to the changes of chemical elements on cell membrane of P. gingivalis, which may result in a disturbance in the microecologic balance of subgingival microbes and eventually contribute to periodontal diseases.