BACKGROUND: Lung cancer is a major threat to human health. The molecular mechanisms related to the occurrence and development of lung cancer are complex and poorly known. Exploring molecular markers related to the development of lung cancer is helpful to improve the effect of early diagnosis and treatment. Long non-coding RNA (lncRNA) THAP7-AS1 is known to be highly expressed in gastric cancer, but has been less studied in other cancers. The aim of the study is to explore the role and mechanism of methyltransferase-like 3 (METTL3) mediated up-regulation of N6-methyladenosine (m6A) modified lncRNA THAP7-AS1 expression in promoting the development of lung cancer. METHODS: Samples of 120 lung cancer and corresponding paracancerous tissues were collected. LncRNA microarrays were used to analyze differentially expressed lncRNAs. THAP7-AS1 levels were detected in lung cancer, adjacent normal tissues and lung cancer cell lines by quantitative reverse transcription-polymerase chain reaction (qRT-PCR). The diagnostic value of THAP7-AS1 in lung cancer and the relationship between THAP7-AS1 expression and survival rate and clinicopathological parameters were analyzed. Bioinformatics analysis, methylated RNA immunoprecipitation (meRIP), RNA pull-down and RNA-immunoprecipitation (RIP) assay were used to investigate the molecular regulation mechanism of THAP7-AS1. Cell proliferation, migration, invasion and tumorigenesis of SPC-A-1 and NCI-H1299 cells were determined by MTS, colony-formation, scratch, Transwell and xenotransplantation in vivo, respectively. Expression levels of phosphoinositide 3-kinase/protein kenase B (PI3K/AKT) signal pathway related protein were detected by Western blot. RESULTS: Expression levels of THAP7-AS1 were higher in lung cancer tissues and cell lines (P<0.05). THAP7-AS1 has certain diagnostic value in lung cancer [area under the curve (AUC)=0.737], and its expression associated with overall survival rate, tumor size, tumor-node-metastasis (TNM) stage and lymph node metastasis (P<0.05). METTL3-mediated m6A modification enhanced THAP7-AS1 expression. The cell proliferation, migration, invasion and the volume and mass of transplanted tumor were all higher in the THAP7-AS1 group compared with the NC group and sh-NC group of SPC-A-1 and NCI-H1299 cells, while the cell proliferation, migration and invasion were lower in the sh-THAP7-AS1 group (P<0.05). THAP7-AS1 binds specifically to Cullin 4B (CUL4B). The cell proliferation, migration, invasion, and expression levels of phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha (PIK3CA), phosphoinositide-3 kinase, catalytic subunit delta (PIK3CD), phospho-phosphatidylinositol 3-kinase (p-PI3K), phospho-protein kinase B (p-AKT) and phospho-mammalian target of rapamycin (p-mTOR) were higher in the THAP7-AS1 group compared with the Vector group of SPC-A-1 and NCI-H1299 cells (P<0.05). CONCLUSIONS LncRNA THAP7-AS1 is stably expressed through m6A modification mediated by METTL3, and combines with CUL4B to activate PI3K/AKT signal pathway, which promotes the occurrence and development of lung cancer.
Humans ; Lung Neoplasms/pathology* ; RNA, Long Noncoding/metabolism* ; Phosphatidylinositol 3-Kinases/metabolism* ; Up-Regulation ; Proto-Oncogene Proteins c-akt/metabolism* ; Cell Line, Tumor ; Cell Proliferation/genetics* ; Gene Expression Regulation, Neoplastic ; Methyltransferases/metabolism* ; Cullin Proteins/genetics*

OBJECTIVE: To determine whether monotropein has an anticancer effect and explore its potential mechanisms against colorectal cancer (CRC) through network pharmacology and molecular docking combined with experimental verification. METHODS: Network pharmacology and molecular docking were used to predict potential targets of monotropein against CRC. Cell counting kit assay, plate monoclonal assay and microscopic observation were used to investigate the antiproliferative effects of monotropein on CRC cells HCT116, HT29 and LoVo. Flow cytometry and scratch assay were used to analyze apoptosis and cell cycle, as well as cell migration, respectively in HCT116, HT29, and LoVo cells. Western blotting was used to detect the expression of proteins related to apoptosis, cell cycle, and cell migration, and the expression of proteins key to the Akt pathway. RESULTS: The Gene Ontology and Reactome enrichment analyses indicated that the anticancer potential of monotropein against CRC might be involved in multiple cancer-related signaling pathways. Among these pathways, RAC-beta serine/threonine-protein kinase (Akt1, Akt2), cyclin-dependent kinase 6 (CDK6), matrix metalloproteinase-9 (MMP9), epidermal growth factor receptor (EGFR), cell division control protein 42 homolog (CDC42) were shown as the potential anticancer targets of monotropein against CRC. Molecular docking suggested that monotropein may interact with the 6 targets (Akt1, Akt2, CDK6, MMP9, EGFR, CDC42). Subsequently, cell activity of HCT116, HT29 and LoVo cell lines were significantly suppressed by monotropein (P<0.05). Furthermore, our research revealed that monotropein induced cell apoptosis by inhibiting Bcl-2 and increasing Bax, induced G₁-S cycle arrest in colorectal cancer by decreasing the expressions of CyclinD1, CDK4 and CDK6, inhibited cell migration by suppressing the expressions of CDC42 and MMP9 (P<0.05), and might play an anticancer role through Akt signaling pathway. CONCLUSION Monotropein exerts its antitumor effects primarily by arresting the cell cycle, causing cell apoptosis, and inhibiting cell migration. This indicates a high potential for developing novel medication for treating CRC.
Humans ; Proto-Oncogene Proteins c-akt/metabolism* ; Cell Proliferation ; Matrix Metalloproteinase 9 ; Molecular Docking Simulation ; Cell Cycle ; ErbB Receptors ; Apoptosis ; Colorectal Neoplasms/pathology* ; Cell Line, Tumor

Pancreatic cancer has an insidious onset and lacks effective treatment methods, which is one of the tumors with the worst prognosis, so it is urgent to explore new treatment directions. Metabolic reprogramming is one of the important hallmarks of tumors. Pancreatic cancer cells in the harsh tumor microenvironment have comprehensively increased cholesterol metabolism in order to maintain strong metabolic needs, and cancer associated fibroblasts also provide cancer cells with a large amount of lipids. Cholesterol metabolism reprogramming involves the changes in the synthesis, uptake, esterification and metabolites of cholesterol, which are closely related to the proliferation, invasion, metastasis, drug resistance, and immunosuppression of pancreatic cancer. Inhibition of cholesterol metabolism has obvious anti-tumor effect. In this paper, the important effects and complexity of cholesterol metabolism in pancreatic cancer were comprehensively reviewed from perspectives of risk factors for pancreatic cancer, energy interaction between tumor-related cells, key targets of cholesterol metabolism and its targeted drugs. Cholesterol metabolism has a strict regulation and feedback mechanism, and the effect of single-target drugs in clinical application is not clear. Therefore, multi-target therapy of cholesterol metabolism is a new direction for pancreatic cancer treatment.
Humans ; Pancreatic Neoplasms/pathology* ; Cholesterol/metabolism* ; Tumor Microenvironment

Lamin B1 (LMNB1) is highly expressed in liver cancer tissues, and its influence and mechanism on the proliferation of hepatocellular carcinoma cells were explored by knocking down the expression of the protein. In liver cancer cells, siRNAs were used to knock down LMNB1. Knockdown effects were detected by Western blotting. Changes in telomerase activity were detected by telomeric repeat amplification protocol assay (TRAP) experiments. Telomere length changes were detected by quantitative real-time polymerase chain reaction (qPCR). CCK8, cloning formation, transwell and wound healing were performed to detect changes in its growth, invasion and migration capabilities. The lentiviral system was used to construct HepG2 cells that steadily knocked down LMNB1. Then the changes of telomere length and telomerase activity were detected, and the cell aging status was detected by SA-β-gal senescence staining. The effects of tumorigenesis were detected by nude mouse subcutaneous tumorigenesis experiments, subsequent histification staining of tumors, SA-β-gal senescence staining, fluorescence in situ hybridization (FISH) for telomere analysis and other experiments. Finally, the method of biogenesis analysis was used to find the expression of LMNB1 in clinical liver cancer tissues, and its relationship with clinical stages and patient survival. Knockdown of LMNB1 in HepG2 and Hep3B cells significantly reduced telomerase activity, cell proliferation, migration and invasion abilities. Experiments in cells and tumor formation in nude mice had demonstrated that stable knockdown of LMNB1 reduced telomerase activity, shortened telomere length, senesced cells, reduced cell tumorigenicity and KI-67 expression. Bioinformatics analysis showed that LMNB1 was highly expressed in liver cancer tissues and correlated with tumor stage and patient survival. In conclusion, LMNB1 is overexpressed in liver cancer cells, and it is expected to become an indicator for evaluating the clinical prognosis of liver cancer patients and a target for precise treatment.
Animals ; Mice ; Telomerase/metabolism* ; Carcinoma, Hepatocellular/genetics* ; Liver Neoplasms/genetics* ; Telomere Shortening ; In Situ Hybridization, Fluorescence ; Mice, Nude ; Telomere/pathology* ; Carcinogenesis

The research on androgen receptor (AR) in breast cancer is advancing.Although the prognostic value of AR in triple negative breast cancer (TNBC) is controversial,a variety of studies have demonstrated that the lack of AR expression exacerbates disease progression.Moreover,the TNBC subtype of AR(-) is more aggressive than that of AR(+) due to the lack of prognostic biomarkers and therapeutic targets.With the discovery and deepening research of novel therapeutic targets such as phosphatidylinositol 3-kinase/protein kinase B/mammalian target of rapamycin and S-phase kinase-associated protein 2 signaling pathways,as well as the emerging of immunotherapies,the treatment options for TNBC are increasing.Regarding the role of AR in TNBC,the studies about the tumor biology of AR(-)TNBC and novel biomarkers for improved management of the disease remain insufficient.In this review,we summarize the research progress of AR in TNBC,put forward avenues for future research on TNBC,and propose potential biomarkers and therapeutic strategies that warrant investigation.
Humans ; Triple Negative Breast Neoplasms/pathology* ; Receptors, Androgen/metabolism* ; Prognosis ; Biomarkers ; Signal Transduction

Objective To study the pathological types,expression of mismatch repair protein,human epidermal growth factor receptor 2(HER2),and Pan-TRK,and Epstein-Barr virus(EBV)infection in patients with colorectal cancer resected in Tibet. Methods A total of 79 patients with colorectal cancer resected in Tibet Autonomous Region People's Hospital from December 2013 to July 2021 were enrolled in this study.The clinical and pathological data of the patients were collected.The expression of mismatch repair protein,HER2,and Pan-TRK was detected by immunohistochemical(IHC)staining,and detection of HER2 gene by fluorescence in situ hybridization(FISH)in the patients with HER2 IHC results of 2+ or above.EBV was detected by in situ hybridization with EBV-encoded small RNA. Results A total of 79 colorectal cancer patients were included in this study,with the male-to-female ratio of 1.26:1 and the mean age of(57.06±12.74)years(24-83 years).Among them,4 patients received preoperative neoadjuvant therapy.Colonic cancer and rectal cancer occurred in 57(57/79,72.15%,including 31 and 26 in the right colon and left colon,respectively)and 22(22/79,27.85%)patients,respectively.The maximum diameter of tumor varied within the range of 1-20 cm,with the mean of(6.61±3.33)cm.Among the 79 colorectal cancer patients,75(75/79,94.94%)patients showed adenocarcinoma.Lymph node metastasis occurred in 12(12/21,57.14%)out of the 21 patients with severe tumor budding,13(13/23,56.52%)out of the 23 patients with moderate tumor budding,and 2(2/31,6.45%)out of the 31 patients with mild tumor budding,respectively.The lymph node metastasis rate showed differences between the patients with severe/moderate tumor budding and the patients with mild tumor budding(all P<0.001).The IHC staining showed that mismatch repair protein was negative in 10(10/65,15.38%)patients,including 5 patients with both MSH2 and MSH6 negative,4 patients with both MLH1 and PMS2 negative,and 1 patient with MSH6 negative.Pan-TRK was negative in 65 patients.The IHC results of HER2 showed 0 or 1+ in 60 patients and 2+ in 5 patients.FISH showed no positive signal in the 5 patients with HER2 IHC results of 2+.The detection with EBV-encoded small RNA showed positive result in 1(1/65,1.54%)patient. Conclusions Non-specific adenocarcinoma of the right colon is the most common in the patients with colorectal cancer resected in Tibet,and 15% of the patients showed mismatch repair protein defects.EBV-associated colorectal carcer is rare,Pan-TRK expression and HER2 gene amplification are seldom.The colorectal cancer patients with moderate and severe tumor budding are more likely to have lymph node metastasis.
Adult ; Aged ; Female ; Humans ; Male ; Middle Aged ; Adenocarcinoma ; Biomarkers, Tumor/genetics* ; Colorectal Neoplasms/pathology* ; DNA Mismatch Repair ; DNA-Binding Proteins/genetics* ; Epstein-Barr Virus Infections/diagnosis* ; Herpesvirus 4, Human/metabolism* ; In Situ Hybridization, Fluorescence ; Lymphatic Metastasis ; Tibet ; Young Adult ; Aged, 80 and over

OBJECTIVE: To investigate the prognostic value and mechanism of long non-coding RNA DLEU1(LncRNA DLEU1) in osteosarcoma. METHODS: The tissue samples and clinical data of 86 patients with osteosarcoma treated by orthopaedic surgery in our hospital from January 2012 to December 2014 were retrospectively collected. The expression of LncRNA DLEU1 in pathological tissues was detected by qRT-PCR, then the patients were divided into high and low expression of LncRNA DLEU1 groups. Osteosarcoma cell line HOS was divided into two groups, down-regulated expression group (si-DLEU1 group) and negative control group (si-NC group). LncRNA DLEU1 siRNA and negative control sequence were transfected by Lipofectamine 3000. Chi-square test was used to analyze the relationship between the expression of LncRNA DLEU1 and the clinicopathological factors of osteosarcoma. Kaplan-Meier method was used to compare the difference of the overall survival rate of osteosarcoma patients between the high and low expression groups of LncRNA DLEU1. The risk factors affecting the overall survival rate of osteosarcoma were analyzed by single factor and multifactor analysis. The number of invasive cells in the two groups was determined and compared by Transwell assay. RESULTS: The expression of LncRNA DLEU1 in osteosarcoma tissue was higher than that in adjacent tissues (P<0.001). The expression of LncRNA DLEU1 in human osteosarcoma cell lines (MG-63, U-2 OS, and HOS) was significantly higher than that in human osteoblast line hFOB 1.19 (P<0.001). The expression of LncRNA DLEU1 was significantly correlated with Enneking stage (P<0.001), distant metastasis (P=0.016), and histological grade (P=0.028). The 1-year overall survival rate of the LncRNA DLEU1 high expression group was significantly higher than that of the low expression group (90.7% vs 60.5%, P<0.001). The 5-year overall survival rate of the LncRNA DLEU1 high expression group was significantly higher than that of the low expression group (32.6% vs 11.6%, P<0.001). Univariate analysis showed that Enneking stage (P<0.001), tumor size (P=0.043), distant metastasis (P<0.001), histological grade (P<0.001), and expression of LncRNA DLEU1 (P<0.001) were risk factors for overall survival of osteosarcoma patients. Multivariate analysis showed that high expression of LncRNA DLEU1 [HR=1.948, 95% CI(1.141, 3.641), P=0.012] and distant metastasis[HR=4.108, 95% CI(2.169, 7.780), P<0.001] were independent risk factors for overall survival of osteosarcoma patients. The number of invasive cells in si-DLEU1 group was significantly lesser than that in si-NC group(139±13 vs 357±31, P<0.001). CONCLUSION High expression of LncRNA DLEU1 is a molecular marker affecting the prognosis of osteosarcoma patients. Downregulation of LncRNA DLEU1 can inhibit the invasion of osteosarcoma cells.
Humans ; Prognosis ; RNA, Long Noncoding/metabolism* ; Retrospective Studies ; Cell Proliferation/genetics* ; Cell Line, Tumor ; Osteosarcoma/genetics* ; Bone Neoplasms/pathology*

Objective To investigate the effects of microRNA497 (miR-497) on the metastasis of gastric cancer and its possible molecular mechanism. Methods SGC-7901 gastric cancer parent cells were cultured in an ultra-low adhesion environment, and the anoikis resistance model of SGC-7901 cells was created after re-adhesion. Clone formation assay, flow cytometry, Transwell^TM test and scratch healing test were used to detect the differences of biological behavior compared with their parent cells. Fluorescence quantitative PCR was performed to detect the expression of miR-497. Western blot analysis was used to detect the changes of key proteins of Wnt/β-catenin signaling pathway and epithelial mesenchymal transformation (EMT) related proteins such as vimentin and E-cadherin. Parent cells and anoikis resistant SGC-7901 cells were transfected with miR-497 inhibitor or miR-497 mimic, and CCK-8 assay was used to detect the proliferation activity. Transwell^TM invasion assay was performed to detect the invasion ability of cells. Transwell^TM migration test and scratch healing assay was used to determine the migration ability. Western blot analysis was used to detect the expressions of Wnt1, β-catenin, vimentin and E-cadherin. By transfecting miR-497 mimic into the anoikis resistance SGC-7901 cells and inoculating them subcutaneously in nude mice, the changes in the volume and mass of tumor tissues were measured and recorded. Western blot analysis was used to determine the expressions of Wnt1, β-catenin, vimentin and E-cadherin of tumor tissues. Results Compared with the parent cells, the anoikis resistance SGC-7901 gastric cancer cells had faster proliferation rate, stronger colony formation, lower apoptosis rate, stronger invasion and migration ability. The expression of miR-497 was significantly decreased. After down-regulation of miR-497, the proliferation ability, invasion and migration ability were significantly enhanced. The expressions of Wnt1, β-catenin and vimentin increased significantly, while E-cadherin decreased notably. The results of up-regulation miR-497 were the opposite. The tumor growth rate, tumor volume and mass of miR-497 overexpression group were significantly lower than those of control group. The expressions of Wnt1, β-catenin and vimentin decreased significantly, while the expression of E-cadherin increased significantly. Conclusion The expression of miR-497 is low in the anoikis resistance SGC-7901 cells. miR-497 can inhibit the growth and metastasis of gastric cancer cells by blocking Wnt/β-catenin signaling pathway and EMT.
Animals ; Mice ; Humans ; beta Catenin/metabolism* ; MicroRNAs/metabolism* ; Vimentin/metabolism* ; Stomach Neoplasms/pathology* ; Anoikis/genetics* ; Wnt Signaling Pathway/genetics* ; Mice, Nude ; Cell Proliferation/genetics* ; Cadherins/genetics* ; Cell Line, Tumor ; Epithelial-Mesenchymal Transition/genetics* ; Cell Movement/genetics*

A complete proteomics study characterizing active androgen receptor (AR) complexes in prostate cancer (PCa) cells identified a diversity of protein interactors with tumorigenic annotations, including known RNA splicing factors. Thus, we chose to further investigate the functional role of AR-mediated alternative RNA splicing in PCa disease progression. We selected two AR-interacting RNA splicing factors, Src associated in mitosis of 68 kDa (SAM68) and DEAD (Asp-Glu-Ala-Asp) box helicase 5 (DDX5) to examine their associative roles in AR-dependent alternative RNA splicing. To assess the true physiological role of AR in alternative RNA splicing, we assessed splicing profiles of LNCaP PCa cells using exon microarrays and correlated the results to PCa clinical datasets. As a result, we were able to highlight alternative splicing events of clinical significance. Initial use of exon-mini gene cassettes illustrated hormone-dependent AR-mediated exon-inclusion splicing events with SAM68 or exon-exclusion splicing events with DDX5 overexpression. The physiological significance in PCa was investigated through the application of clinical exon array analysis, where we identified exon-gene sets that were able to delineate aggressive disease progression profiles and predict patient disease-free outcomes independently of pathological clinical criteria. Using a clinical dataset with patients categorized as prostate cancer-specific death (PCSD), these exon gene sets further identified a select group of patients with extremely poor disease-free outcomes. Overall, these results strongly suggest a nonclassical role of AR in mediating robust alternative RNA splicing in PCa. Moreover, AR-mediated alternative spicing contributes to aggressive PCa progression, where we identified a new subtype of lethal PCa defined by AR-dependent alternative splicing.
Humans ; Male ; Alternative Splicing ; Cell Line, Tumor ; DEAD-box RNA Helicases/metabolism* ; Disease Progression ; Gene Expression Regulation, Neoplastic ; Prostatic Neoplasms/pathology* ; Receptors, Androgen/metabolism* ; RNA Splicing Factors/metabolism*

OBJECTIVES: To investigate the prevalence of pathogenic germline mutations of mismatch repair (MMR) genes in prostate cancer patients and its relationship with clinicopathological characteristics. METHODS: Germline sequencing data of 855 prostate cancer patients admitted in Fudan University Shanghai Cancer Center from 2018 to 2022 were retrospectively analyzed. The pathogenicity of mutations was assessed according to the American College of Medical Genetics and Genomics (ACMG) standard guideline, Clinvar and Intervar databases. The clinicopathological characteristics and responses to castration treatment were compared among patients with MMR gene mutation (MMR⁺ group), patients with DNA damage repair (DDR) gene germline pathogenic mutation without MMR gene (DDR⁺MMR^－ group) and patients without DDR gene germline pathogenic mutation (DDR^－ group). RESULTS: Thirteen (1.52%) MMR⁺ patients were identified in 855 prostate cancer patients, including 1 case with MLH1 gene mutation, 6 cases with MSH2 gene mutation, 4 cases with MSH6 gene mutation and 2 cases with PMS2 gene mutation. 105 (11.9%) patients were identified as DDR gene positive (except MMR gene), and 737 (86.2%) patients were DDR gene negative. Compared with DDR^－ group, MMR⁺ group had lower age of onset (P<0.05) and initial prostate-specific antigen (PSA) (P<0.01), while no significant differences were found between the two groups in Gleason score and TMN staging (both P>0.05). The median time to castration resistance was 8 months (95%CI: 6 months-not achieved), 16 months (95%CI: 12-32 months) and 24 months (95%CI: 21-27 months) for MMR⁺ group, DDR⁺MMR^－ group and DDR^－ group, respectively. The time to castration resistance in MMR⁺ group was significantly shorter than that in DDR⁺MMR^－ group and DDR^－ group (both P<0.01), while there was no significant difference between DDR⁺MMR^－ group and DDR^－ group (P>0.05). CONCLUSIONS MMR gene mutation testing is recommended for prostate cancer patients with early onset, low initial PSA, metastasis or early resistance to castration therapy.
Male ; Humans ; Prostate-Specific Antigen/genetics* ; Germ-Line Mutation ; Retrospective Studies ; DNA Mismatch Repair/genetics* ; DNA-Binding Proteins/metabolism* ; China ; Prostatic Neoplasms/pathology*