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The latest 2021 WHO classification redefines glioblastoma (GBM) as the hierarchical reporting standard by eliminating glioblastoma, IDH-mutant and only retaining the tumor entity of "glioblastoma, IDH-wild type." Knowing that subclassification of tumors based on molecular features is supposed to facilitate the therapeutic choice and increase the response rate in cancer patients, it is necessary to carry out molecular classification of the newly defined GBM. Although differentiation trajectory inference based on single-cell sequencing (scRNA-seq) data holds great promise for identifying cell heterogeneity, it has not been used in the study of GBM molecular classification. Single-cell transcriptome sequencing data from 10 GBM samples were used to identify molecular classification based on differentiation trajectories. The expressions of identified features were validated by public bulk RNA-sequencing data. Clinical feasibility of the classification system was examined in tissue samples by immunohistochemical (IHC) staining and immunofluorescence, and their clinical significance was investigated in public cohorts and clinical samples with complete clinical follow-up information. By analyzing scRNA-seq data of 10 GBM samples, four differentiation trajectories from the glioblastoma stem cell-like (GSCL) cluster were identified, based on which malignant cells were classified into five characteristic subclusters. Each cluster exhibited different potential drug sensitivities, pathways, functions, and transcriptional modules. The classification model was further examined in TCGA and CGGA datasets. According to the different abundance of five characteristic cell clusters, the patients were classified into five groups which we named Ac-G, Class-G, Neo-G, Opc-G, and Undiff-G groups. It was found that the Undiff-G group exhibited the worst overall survival (OS) in both TCGA and CGGA cohorts. In addition, the classification model was verified by IHC staining in 137 GBM samples to further clarify the difference in OS between the five groups. Furthermore, the novel biomarkers of glioblastoma stem cells (GSCs) were also described. In summary, we identified five classifications of GBM and found that they exhibited distinct drug sensitivities and different prognoses, suggesting that the new grouping system may be able to provide important prognostic information and have certain guiding significance for the treatment of GBM, and identified the GSCL cluster in GBM tissues and described its characteristic program, which may help develop new potential therapeutic targets for GSCs in GBM. [ABSTRACT FROM AUTHOR]

BACKGROUND: Gastric cancer is one of the most common malignancies worldwide. Recent studies reported that Piwil3 was overexpressed in various cancers, including gastric cancer (GC). This study was intended to investigate its function and mechanism in GC progress. METHODS: Quantitative real time PCR(RT-PCR) and western blotting assays were utilized to measure mRNA and protein expression levels, respectively. SiRNA transfection was performed to suppress the expression of Piwil3. CCK-8 assay, cell invasion and migration assays were used to determine the cell proliferative, cell invasive and migratory ability. RESULTS: The expression of Piwil3 was significantly increased in GC tissues compared with matched normal tissues. The specific siRNA significantly inhibited the protein and mRNA expressions of Piwil3, and effectively inhibited the proliferation and induced G0/G1 phase arrest in GC cells. Downregulation of Piwil3 significantly suppressed the migration and invasion of GC cells. Moreover, the downregulation of Piwil3 also significantly suppressed the tumor volumes in nude mice. Mechanism investigation showed that the downregulation of Piwil3 significantly decreased the mRNA and protein expressions of metastasisrelated genes, including RhoC, MTA1, MMP2 and MMP9, and also modulated the phosphorylation levels of JAK2 and STAT3 but not their protein levels. CONCLUSIONS: These findings indicate that overexpression of Piwil3 promotes the proliferation, migration and invasion of GC cells partially through JAK2/STAT3 signal pathway. [ABSTRACT FROM AUTHOR]

Parathyroid hormone-related protein (PTHrP) has been identified to play a crucial role in osteolysis formation and stromal cell (GCTSC) proliferation in giant cell tumor (GCT). MiR-126-5p is an intronic miRNA identified as tumor suppressor in many tumors, but its role in GCT is poorly understood. We found that miR-126-5p was decreased in GCT and could directly regulate PTHrP expression. Furthermore, miR-126-5p could control osteoclast (OC) differentiation, GCTSC proliferation and osteolysis formation in GCT through negative regulation of PTHrP. Thus, these results suggest that miR-126-5p could directly target PTHrP and have a tumor suppressor function in GCT. [ABSTRACT FROM AUTHOR]

The present study investigated the effects of 5-azacytidine (5-azaC) on the expression level of the human runt-related transcription factor 3 (RUNX3) gene and the biological behavior of esophageal carcinoma Ecal09 cells. The effect of the demethylation reagent 5-azaC on the viability of Ecal09 cells was detected by the MTT assay, which demonstrated that 5-azaC inhibited the viability of Ecal09 cells in a time- and dose-dependent manner. Although demethylation of other genes may occur following treatment with 5-azaC, we focused on the RUNX3 gene. When treated with 5-azaC at hypoxic levels, the expression of RUNX3 increased and the methylation degree of the RUNX3 gene was decreased significantly in Ecal09 cells. 5-azaC at 50 jaM demonstrated the highest RUNX3-induction activity, inducing RUNX3 mRNA and protein expression, and decreasing the degree of methylation of the RUNX3 gene. Methylation specific PCR indicated that 5-azaC induced RUNX3 expression through demethylation. The abilities of migration and invasion of Ecal09 cells were inhibited by 5-azaC. The growth of Ecal09 cells treated with 5-azaC in vivo was detected by a tumorigenesis experiment. 5-azaC inhibited the growth of Ecal09 xenografts in nude mice. Taken together, our findings demonstrated that the RUNX3 gene is hypermethylated in Ecal09 cells and that 5-azaC induces the expression of the RUNX3 gene by demethylation, which inhibits the proliferation, migration and invasion of Ecal09 cells. [ABSTRACT FROM AUTHOR]

Background: Gastric cancer is highly aggressive disease. Despite advances in diagnosis and therapy, the prognosis is still poor. Various genetic and molecular alterations are found in gastric cancer that underlies the malignant transformation of gastric mucosa during the multistep process of gastric cancer pathogenesis. The detailed mechanism of the gastric cancer development remains uncertain. In present study we investigated the potential role of stathmin1 gene in gastric cancer tumorigenesis and examined the usefulness of RNA interference (RNAi) targeting stathmin1 as a form of gastric cancer treatment. Methods: A lentiviral vector encoding a short hairpin RNA (shRNA) targeted against stathmin1 was constructed and transfected into the packaging cells HEK 293 T and the viral supernatant was collected to transfect MKN-45 cells. The transwell chemotaxis assay and the CCK-8 assay were used to measure migration and proliferation of tumor cells, respectively. Quantitative real-time PCR and western blotting were used to detect the expression levels of stathmin1. Results: Lentivirus mediated RNAi effectively reduced stathmin1 expression in gastric cells. Significant decreases in stathmin1 mRNA and protein expression were detected in gastric cells carrying lentiviral stathmin-shRNA vector and also significantly inhibited the proliferation, migration in gastric cancer cells and tumorigenicity in Xenograft Animal Models. Conclusions: Our findings suggest that stathmin1 overexpression is common in gastric cancer and may play a role in its pathogenesis. Lentivirus mediated RNAi effectively reduced stathmin1 expression in gastric cells. In summary, shRNA targeting of stathmin1 can effectively inhibits human gastric cancer cell growth in vivo and may be a potential therapeutic strategy for gastric cancer. [ABSTRACT FROM AUTHOR]

Objective: The present study was performed to investigate the relationship between the concentration of zinc, copper, and manganese and the incidence and prognosis of esophageal squamous cell cancer (ESCC). Material and method: The study was conducted on 36 patients with ESCC and all patients underwent esophagectomy. The cancerous tissue samples and the normal tissue samples came from the patients with ESCC. The concentration of zinc, copper, and manganese was measured by flame atomic absorption spectroscopy and comparison was made using Student's t-test. Results: The content of zinc and manganese in cancerous tissues was significantly lower than that in the normal tissues, respectively (p <0.01, p <0.01). In contrast, copper level in cancerous tissues was significantly higher than that in the normal tissues (p <0.01). And the copper/zinc ratio was higher in cancerous tissues compared to that in the normal tissues (p < 0.01). Zinc level in patients having lymph node metastasis was significantly lower than in the control group (p < 0.05). In contrast, copper level in patients having lymph node metastasis was significantly higher than in the control group (p <0.01). And the copper/zinc ratio was higher in patients having lymph node metastasis com- pared to that in the control group (p < 0.01). There was a significant decrease in mean zinc and manganese in cancerous tissues with worse histologic grading, respectively. There was a significant increase in mean copper in cancerous tissues with worse histologic grading. Conclusions: Zinc, copper, and manganese level may be associated with the incidence, aggression and prognosis of ESCC. [ABSTRACT FROM AUTHOR]

Purpose: To study whether B7-H3 and B7-H4 proteins can be candidate drug targets for preventing and treating hepatoma. Methods: Western blot assay was used to study the expressions of B7-H3 and B7-H4 proteins and the effect of sorafenib on their expressions in different human hepatoma cell lines (HepG2, Hep3B, BEL- 7402, BEL-7404, BEL-7405, QGY-7701, QGY-7703, SMMC-7721, MHCC97H, MHCC97L, HCCLM3 and HCCLM6). 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was used to study the cytotoxicity of sorafenib against different human hepatoma cell lines. Results: The expressions of B7-H3 (0.26 - 0.84 μM) and B7-H4 (0.18 - 0.78 μM) proteins in different human hepatoma cell lines were significantly (p < 0.01) up-regulated, compared with that of the normal human liver cell line (HL-7702) (0.09 and 0.08 μM). Sorafenib was cytotoxic on Hep3B, BEL-7404, MHCC97H, HCCLM3 and HCCLM6 cells with half-maximal inhibitory concentration (IC50) of 14.56, 9.14, 9.46, 17.21 and 9.29 μM, respectively. After treatment with sorafenib at concentrations of 5, 10 and 20 μM, the expressions of B7-H3 protein in MHCC97H, HCCLM3 and HCCLM6 cells and the expressions of B7-H4 protein in Hep3B, BEL-7404 and MHCC97H cells were significantly (p < 0.01) down-regulated, compared with that of the control. Conclusion: Over-expression of B7-H3 and B7-H4 proteins is common in different human hepatoma cell lines and thus, B7-H3 and B7-H4 proteins may be regarded as candidate drug targets for preventing and treating hepatoma. [ABSTRACT FROM AUTHOR]

Neoadjuvant tyrosine kinase inhibitor (TKI) therapy is an important treatment option for advanced renal cell carcinoma (RCC). Many RCC patients may fail to respond or be resistant to TKI therapy. We aimed to explore the key mechanisms of neoadjuvant therapy résistance. We obtained tumor samples from matched pre-treatment biopsy and post-treatment surgical samples and performed single-cell RNA sequencing. Sunitinib-resistant ccRCC cell lines were established. Ferroptosis was detected by ferrous ion and lipid peroxidation levels. Tumor growth and resistance to Sunitinib was validated in vitro and vivo. Immunohistochemistry was used to validate the levels key genes and lipid peroxidation. Multi-center cohorts were included, including TCGA, ICGC, Checkmate-025 and IMmotion151 clinical trial. Survival analysis was performed to identify the associated clinical and genomic variables. Intratumoral heterogeneity was first described in the whole neoadjuvant management. The signature of endothelial cells was correlated with drug sensitivity and progression-free survival. Ferroptosis was shown to be the key biological program in malignant cell resistance. We observed tissue lipid peroxidation was negatively correlated with IL6 and tumor response. TKI-resistant cell line was established. SLC7A11 knockdown promoted cell growth and lipid peroxidation, increased the ferroptosis level, and suppressed the growth of tumor xenografts significantly (P < 0.01). IL6 could reverse the ferroptosis and malignant behavior caused by SLC7A11 (−) via JAK2/STAT3 pathway, which was rescued by the ferroptosis inducer Erastin. Our data indicate that ferroptosis is a novel strategy for advanced RCC treatment, which activated by IL6, providing a new idea for resistance to TKIs. • Fill the gap in single-cell data of paired samples in pre- and post-neoadjuvant therapy of ccRCC. • Find the key cell type in RCC resistance to treatment based on multi-omics and multi-center data analyses. • New sight to the role of TILs in treatment of RCC. • The evolution of TKI-resistant tumor cells may be caused by IL6-induced ferroptosis inhibition. [ABSTRACT FROM AUTHOR]

Although transcriptional effects of androgens have been extensively studied, mechanisms regulating transcription-independent (nongenomic) androgen actions are poorly understood. Previously, we have shown that paxillin, a multidomain adaptor protein, is a critical regulator of testosterone-induced MAPK-signaling during Xenopus oocyte maturation. Here we examine the nongenomic effects of dihydrotestosterone (DHT) in prostate cancer cells, focusing on how paxillin mediates Erk signaling and downstream physiologic actions. We show that in LnCAP cells DHT functions as a growth factor that indirectly activates the EGF-receptor (EGFR) via androgen receptor binding and matrix metalloproteinase-mediated release of EGFR ligands. Interestingly, siRNA-mediated knockdown of paxillin expression in androgen-dependent LnCAP cells as well as in androgen-independent PC3 cells abrogates DHT- and/or EGF-induced Erk signaling. Furthermore, EGFR-induced Erk activation requires Src-mediated phosphorylation of paxillin on tyrosines 31/118. In contrast, paxillin is not required for PKC-induced Erk signaling. However, Erk-mediated phosphorylation of paxiilin on serines 83/126/130 is still needed for both EGFR and PKC-mediated cellular proliferation. Thus, paxillin serves as a specific upstream regulator of Erk in response to receptor-tyrosine kinase signaling but as a general regulator of downstream Erk actions regardless of agonist. Importantly, Erk-mediated serine phosphorylation of paxillin is also required for DHT-induced prostate-specific antigen mRNA expression in LnCAP cells as well as EGF-induced cyclin D1 mRNA expression in PC3 cells, suggesting that paxillin may regulate prostate cancer proliferation by serving as a liaison between extra-nuclear kinase signaling and intra-nuclear transcriptional signals. Thus, paxillin may prove to be a novel diagnostic or therapeutic target in prostate cancer. [ABSTRACT FROM AUTHOR]

Nuclear localization of the androgen receptor (AR) is necessary for its activation as a transcription factor. Defining the mechanisms regulating AR nuclear localization in androgen-sensitive cells and how these mechanisms are dysregulated in castration-resistant prostate cancer (CRPC) cells is fundamentally important and clinically relevant. According to the classical model of AR intracellular trafficking, androgens induce AR nuclear import and androgen withdrawal causes AR nuclear export. The present study has led to an updated model that AR could be imported in the absence of androgens, ubiquitinated, and degraded in the nucleus. Androgen withdrawal caused nuclear AR degradation, but not export. In comparison with their parental androgen-sensitive LNCaP prostate cancer cells, castration-resistant C4-2 cells exhibited reduced nuclear AR polyubiquitination and increased nuclear AR level. We previously identified 3-(4-chlorophenyl)-6,7-dihydro-5H-pyrrolo[1,2-a]imidazole (CPPI) in a high-throughput screen for its inhibition of androgen-independent AR nuclear localization in CRPC cells. The current study shows that CPPI is a competitive AR antagonist capable of enhancing AR interaction with its E3 ligase MDM2 and degradation of AR in the nuclei of CRPC cells. Also, CPPI blocked androgen-independent AR nuclear import. Overall, these findings suggest the feasibility of targeting androgen-independent AR nuclear import and stabilization, two necessary steps leading to AR nuclear localization and activation in CRPC cells, with small molecule inhibitors. [ABSTRACT FROM AUTHOR]

We have previously identified an androgen-responsive gene in rat prostate that shares homology with the acireductone dioxygenase (ARD/ARD') family of metalbinding enzymes involved in methionine salvage. We found that the gene, aci-reductone dioxygenase 1 (ADI1), was downregulated in prostate cancer cells, whereas enforced expression of rat Adi1 in these cells caused apoptosis. Here we report the characterization of human ADI1 in prostate cancer. Androgens induced ADI1 expression in human prostate cancer LNCaP cells, which was not blocked by cycloheximide, indicating that ADI1 is a primary androgen-responsive gene. In human benign prostatic hyperplasia specimens, epithelial cells expressed ADI1. Immunohistochemistry of prostate tumor tissue microarrays showed that benign regions expressed more ADI1 than tumors, suggesting a suppressive role for ADI1 in prostate cancer. Bacterial lysates containing recombinant ADI1 produced a five-fold increase in aci-reductone decay over controls, demonstrating that ADI1 has ARD activity. We generated point mutations at key residues in the metal-binding site of ADI1 to disrupt ARD function, and we found that these mutations did not affect intracellular localization, apoptosis, or colony formation suppression in human prostate cancer cells. Collectively, these observations argue that ADI1 may check prostate cancer progression through apoptosis and that this activity does not require metal binding. [ABSTRACT FROM AUTHOR]