Renal Lesions with Low-level Enhancement on Contrast-enhanced CT Promotes Early Detection of Drug-induced Kidney Injury in Patients Administered Anticancer Drugs.

BACKGROUND: Some patients with cancer-administered anti-cancer drugs may develop renal lesions with low-level enhancement on follow-up abdominal computed tomography (CT). OBJECTIVE: To explore the clinical significance of renal lesions with low-level enhancement on CT after exposure to anti-cancer drugs. METHODS: Medical records of patients with cancer who developed renal lesions on CT after exposure to anti-cancer drugs were retrospectively reviewed. Renal lesions were scored according to the extent of involvement, CT attenuation values of lesions and normal parenchyma were measured on precontrast CT and three phases of contrast-enhanced CT, and changes in serum creatinine (SCr) from one week before exposure to drugs to one week before and after the appearance of renal lesions were recorded. RESULTS: This study included 54 patients (86 lesions). Lesions were slightly lower density on pre-contrast CT, and less enhancing than normal renal parenchyma, especially in the delayed phase. Lesions were wedge-shaped, and involved the renal pyramid and associated renal cortex, as well as, were single or multiple, and occurred in the unilateral or bilateral kidneys. There were patchy and cord-like shadows of increased density in adjacent perirenal adipose tissue. During follow-up, lesions disappeared in 15 patients and persisted in 39 patients without significant progression. There were significant differences in renal lesions and normal renal parenchyma CT attenuation values in each phase of contrast-enhanced CT. Change in SCr level was significantly positively correlated with lesion score. CONCLUSION: Renal lesions with low-level enhancement on CT suggest early drug-induced kidney injury. These findings will inform clinical decision-making.

Polo-like kinase 1 inhibitor NMS-P937 represses nasopharyngeal carcinoma progression via induction of mitotic abnormalities.

Polo-like kinase 1 (PLK1) inhibitor NMS-P937 is a targeted therapeutic agent with good preclinical efficacy in various human cancers, and its therapeutic effect on nasopharyngeal carcinoma (NPC) remains to be determined. Here, to explore biological activity of NMS-P937 in NPC, multiple types of NPC cells were utilized. We tested IC50 values, carried out flow cytometry, western blot analysis analysis, immunofluorescence, and constructed subcutaneous xenograft mouse models. We found that treatment with NMS-P937 increased the proportion of G2/M phase NPC cells, where CyclinB1 expression was upregulated and CyclinE1 expression was downregulated. Besides, NMS-P937 treatment-induced NPC cell apoptosis with increased cleavage of PARP and caspase-3. Mechanistically, NMS-P937 treatment led to aberrant mitosis, causing increased reactive oxygen species (ROS) levels. ROS scavenger N-acetylcysteine partially reversed ROS levels induced by NMS-P937. Furthermore, NMS-P937 administration restrained NPC xenografts growth in nude mice. Overall, NMS-P937 suppressed NPC cell proliferation and increased ROS levels, causing cell cycle abnormalities and apoptosis. NMS-P937 holds great promise as a therapeutic agent for treating nasopharyngeal carcinoma.

PI3K/mTOR inhibitor VS-5584 combined with PLK1 inhibitor exhibits synergistic anti-cancer effects on non-small cell lung cancer.

Small molecule drugs are of significant importance in the treatment of non-small cell lung cancer (NSCLC). Here, we explored biological effects of the PI3K/mTOR inhibitor VS-5584 on NSCLC. Our findings indicated that VS-5584 administration resulted in a dose-dependent inhibition of NSCLC cell proliferation, as well as the induction of apoptosis and cycle arrest. Additionally, we observed a significant increase in intracellular reactive oxygen species (ROS) levels following VS-5584 treatment. The use of the ROS inhibitor N-acetylcysteine (NAC) effectively reduced ROS levels and decreased the proportion of apoptotic cells. Treatment with VS-5584 led to an upregulation of genes associated with apoptosis and cell cycle, such as c-caspase 3 and P21. Conversely, a downregulation of cyclin-dependent kinase 1 (CDK1) expression was observed. Next, transcriptome analyses revealed that VS-5584 treatment altered the abundance of 1520 genes/transcripts in PC-9 cells, one of which was polo-like kinase 1 (PLK1). These differentially expressed genes were primarily enriched in biological processes such as cell cycle regulation and cell apoptosis, which are closely linked to the P53 and apoptosis pathways. Co-treatment with VS-5584 and PLK1 inhibitor NMS-P937 resulted in enhanced cancer cell death, exhibiting synergistic inhibitory activity. Notably, VS-5584 inhibited the growth of NSCLC in a patient-derived xenograft (PDX) mouse model without observable abnormalities in major organs. Overall, VS-5584 effectively suppressed the growth of NSCLC cells both in vitro and in vivo. VS-5584 combined with NMS-P937 exhibited a synergistic effect in inhibiting NSCLC cell growth. These findings suggest that VS-5584 has potential as a therapeutic strategy for treating NSCLC.

Onvansertib inhibits the proliferation and improves the cisplatin-resistance of lung adenocarcinoma via ß-catenin/c-Myc signaling pathway.

Polo-like kinase 1 (PLK1) is a key regulator of cell division, and its abnormal expression is related to the progression and prognosis of cancers. However, the effect of PLK1 inhibitor onvansertib on the growth of lung adenocarcinoma (LUAD) has not been explored. In this study, we performed a series of bioinformatics and experimental analyses to comprehensively investigate the role of PLK1 in LUAD. We used CCK-8 assay and colony formation assay to evaluate the growth inhibitory ability of onvansertib. Furthermore, flow cytometry was applied to exploit the effects of onvansertib on cell cycle, apoptosis, and mitochondrial membrane potential. Moreover, the therapeutic potential of onvansertib was assessed in vivo by using xenograft tumor and patient-derived xenograft (PDX) models. We found that onvansertib significantly induced the apoptosis and inhibited the proliferation and migration of LUAD cells. Mechanistically, onvansertib arrested the cells at G2/M phase and enhanced the levels of reactive oxidative species in LUAD. Accordingly, onvansertib regulated the expression of glycolysis-related genes and improved the cisplatin resistance in LUAD. Notably, the protein levels of ß-catenin and c-Myc were affected by onvansertib. Taken together, our findings provide insight into the function of onvansertib and shed light on the potential clinical application of onvansertib for the treatment of patients with LUAD.

The HOXC-AS2/miR-876-5p/HKDC1 axis regulates endometrial cancer progression in a high glucose-related tumor microenvironment.

The tumor microenvironment (TME) is related to chronic inflammation and is currently identified as a risk factor for the occurrence and development of endometrial cancer (EC). Pyroptosis is a new proinflammatory form of programmed cell death that plays a critical role in the progression of multiple diseases. However, the important role of pyroptosis in high-glucose (HG)-related EC and the underlying molecular mechanisms remain elusive. In the present study, transcriptome high-throughput sequencing revealed significantly higher hexokinase domain-containing 1 (HKDC1) expression in EC patients with diabetes than in EC patients with normal glucose. Mechanistically, HKDC1 regulates HG-induced cell pyroptosis by modulating the production of reactive oxygen species and pyroptosis-induced cytokine release in EC. In addition, HKDC1 regulates TME formation by enhancing glycolysis, promoting a metabolic advantage in lactate-rich environments to further accelerate EC progression. Subsequently, miR-876-5p was predicted to target the HKDC1 mRNA, and HOXC-AS2 was identified to potentially inhibit the miR-876-5p/HKDC1 axis in regulating cell pyroptosis in HG-related EC. Collectively, we elucidated the regulatory role of the HOXC-AS2/miR-876-5p/HKDC1 signal transduction axis in EC cell pyroptosis at the molecular level, which may provide an effective therapeutic target for patients with diabetes who are diagnosed with EC.

An NF-κB/OVOL2 circuit regulates glucose import and cell survival in non-small cell lung cancer.

BACKGROUND: Tumor cells tend to utilize glycolysis rather than aerobic respiration even under aerobic conditions. OVOL2, an inhibitory C2H2 zinc finger transcription factor, is a potential tumor suppressor in cancers. However, the association between OVOL2 and tumor energy metabolism is unknown. METHODS: Western blotting was used to determine the expression of OVOL2 in different non-small cell lung cancer (NSCLC) cell lines and mouse models. The metabolic parameters in NSCLC cells following overexpression or knockdown OVOL2 were examined. To define the mechanism by which OVOL2 regulates aerobic glycolysis, interacting protein of OVOl2 and downstream molecular events were identified by luciferase assay and co-immunoprecipitation. We documented the regulatory mechanism in mouse xenograft models. Finally, clinical relevance of OVOL2, NF-κB signaling and GLUT1 was measured by immunostaining. RESULTS: OVOL2 is downregulated in NSCLC and overexpression of OVOL2 inhibits the survival of cancer cells. Moreover, OVOL2 directly binds to P65 and inhibits the recruitment of P300 but facilitates the binding of HDAC1 to P65, which in turn negatively regulates NF-κB signaling to suppress GLUT1 translocation and glucose import. In contrast, OVOL2 expression is negatively regulated by NF-κB signaling in NSCLC cells via the ubiquitin-proteasome pathway. Re-expression of OVOL2 significantly compromise NF-κB signaling-induced GLUT1 translocation, aerobic glycolysis in NSCLC cells and mouse models. Immunostaining revealed inverse correlations between the OVOL2 and phosphorylated P65 levels and between the OVOL2 and membrane GLUT1 levels, and a strong correlation between the phosphorylated P65 and membrane GLUT1 levels. CONCLUSIONS: These results suggest a regulatory circuit linking NF-κB and OVOL2, which highlights the role of NF-κB signaling and OVOL2 in the modulation of glucose metabolism in NSCLC. Video Abstract.

Evaluating prognostic value and relevant gene signatures of tumor microenvironment characterization in esophageal carcinoma.

BACKGROUND: Tumor microenvironment (TME) cells are an important part of tumor tissues. There is increasing evidence that the TME plays a vital role in tumor prognosis, and is associated with patient survival in various kinds of malignances. To date, very little research has been conducted on how to effectively use TME to better evaluate the prognosis of patients with esophageal carcinoma (EC). The concept of a "TME score" was introduced to better distinguish the prognosis of patients. METHODS: We employed bioinformatic methods to investigate the TME infiltration patterns of 160 patients with EC from the Cancer Genome Atlas (TCGA) cohort. TME clusters were identified using k-means clustering methods with 1,000 resampling times. The significance of the survival difference among patients belonging to different TME clusters was assessed by the log-rank test and Kaplan-Meier survival curves. Correlations between immune cell types and survival were calculated by a Cox regression, and the Pearson correlation coefficient (PCC) was used to measure the relationship among different immune cell types. We classified patient into 2 subtypes based on the optimal breakpoint of TME score determined by R package maxstat. RESULTS: Two TME phenotypes were defined based on the immune cell type fractions, and patients with a high TME score phenotype had a better prognosis than those with a low TME score phenotype. Kaplan-Meier analysis for differentially expressed micro ribonucleic acids (RNAs) and messenger RNAs also showed that different TME score subtypes were significantly associated with the prognosis of EC. Just as tumor mutational burden can predict the efficacy of immunotherapy, the TME score can predict the efficacy of immune checkpoint inhibitors (ICIs). The genomic alterations of 2 TME score subtypes of EC further revealed that genomic instability is prevalent in TMEs, and patients with a low TME score subtype have a more unstable chromosome status than those with a high subtype. CONCLUSIONS: Thus, TME score is an emerging prognostic biomarker for predicting the efficacy of ICIs.

LINC01140 promotes the progression and tumor immune escape in lung cancer by sponging multiple microRNAs.

BACKGROUND: Long intergenic non-protein coding RNA 1140 (LINC01140), a long non-coding RNA, is highly expressed in various cancers; however, its biological functions in lung cancer (LC) progression and immune escape are still unclear. METHODS: Here, to elucidate LINC01140 function, 79 paired LC and paracancerous tissues were collected. LINC01140 expression levels were determined using fluorescence in situ hybridization and qPCR analysis. Cell counting kit-8 (CCK-8) assay and transwell assays were performed. The interaction between microRNAs (miRNAs) and LINC01140 was confirmed using an RNA immunoprecipitation assay. Cytokine-induced killer (CIK) cell phenotypes were analyzed by flow cytometry. Cytokine secretion levels were determined by ELISA. CIK cytotoxicity was assessed by measuring lactate dehydrogenase release. Besides, xenograft tumor mouse models were used to unveil the in vivo function of LINC01140. RESULTS: We found that LINC01140 was highly expressed in human LC tissues and cell lines. High LINC01140 levels were associated with poor survival in patients with LC. LINC01140 upregulation promoted the proliferation, migration, and invasion of LC cells through direct interaction with miR-33a-5p and miR-33b-5p, thereby contributing to c-Myc expression and also inhibited cisplatin-induced cell apoptosis. In subcutaneous tumor xenograft mice, LINC01140 knockdown markedly reduced tumor growth and lung metastasis. Additionally, LINC01140 directly repressed miR-377-3 p and miR-155-5 p expression levels, resulting in the upregulation of their common downstream target programmed death-ligand 1 (PD-L1), a crucial target in LC immunotherapy. Notably, we proved that LINC01140 knockdown, along with CIK administration, suppressed the growth of subcutaneous LC xenografts by decreasing PD-L1 expression in severe combined immunodeficient mice. CONCLUSIONS: Taken together, LINC01140 overexpression protects c-Myc and PD-L1 mRNA from miRNA-mediated inhibition and contributes to the proliferation, migration, invasion, and immune escape of LC cells. These results provide a theoretical basis that LINC01140 is a promising target for LC treatment.

Oncogenic long intervening noncoding RNA Linc00284 promotes c-Met expression by sponging miR-27a in colorectal cancer.

Emerging evidences suggest that long noncoding RNA (lncRNA) plays a vital role in tumorigenesis and cancer progression. Here, the aim of this study is to investigate the biological function of long intervening noncoding RNA Linc00284 in colorectal cancer (CRC). The expression levels of Linc00284, miR-27a and c-Met were evaluated by qPCR and/or Western blotting. Immunohistochemistry was used to detect the expression of Ki67 and Phh3 in tumor tissues. The interaction between Linc00284, miR-27a and c-Met was validated by luciferase reporter assay and RNA immunoprecipitation (RIP) assay. Cell function experiments, including CCK-8, wound-healing and transwell invasion assays, were conducted. The in vivo studies were performed with the subcutaneous tumor xenograft mouse models. Our findings reveal that Linc00284 is upregulated in CRC tissues and colorectal cancer cell lines HCT116 and SW480 in comparison with corresponding para-carcinoma tissues and human fetal colonic mucosa cells FHC. High expression of Linc00284 in tumor tissues is associated with tumor metastasis and predicts a poor clinical outcome in CRC patients. Serum Linc00284 is increased, while miR-27a is decreased in CRC patients compared to healthy controls. ROC curve analysis indicates that serum Linc00284 and miR-27a produce the area under the curve (AUC) value of at 0.8151 and 0.7316 in patients with colorectal cancer compared to healthy individuals, respectively. Additionally, results in vitro and in vivo experiments suggest that Linc00284 silencing significantly suppresses CRC cell proliferation and/or invasion. Mechanistically, Linc00284 promotes c-Met expression by acting as miR-27a sponge, leading to the activation of downstream signaling pathways, thereby causing malignant phenotypes of CRC cells. Taken together, Linc00284 exhibits oncogenic function and the disturbance of Linc00284/miR-27a/c-Met regulatory axis contributes to CRC progression, providing new insight into the pathogenesis of colorectal cancer. Importantly, the expression levels of serum Linc00284 and miR-27a may serve as clinical biomarkers for CRC diagnosis.

Cancer cachexia: molecular mechanism and pharmacological management.

Cancer cachexia often occurs in malignant tumors and is a multifactorial and complex symptom characterized by wasting of skeletal muscle and adipose tissue, resulting in weight loss, poor life quality and shorter survival. The pathogenic mechanism of cancer cachexia is complex, involving a variety of molecular substrates and signal pathways. Advancements in understanding the molecular mechanisms of cancer cachexia have provided a platform for the development of new targeted therapies. Although recent outcomes of early-phase trials have showed that several drugs presented an ideal curative effect, monotherapy cannot be entirely satisfactory in the treatment of cachexia-associated symptoms due to its complex and multifactorial pathogenesis. Therefore, the lack of definitive therapeutic strategies for cancer cachexia emphasizes the need to develop a better understanding of the underlying mechanisms. Increasing evidences show that the progression of cachexia is associated with metabolic alternations, which mainly include excessive energy expenditure, increased proteolysis and mitochondrial dysfunction. In this review, we provided an overview of the key mechanisms of cancer cachexia, with a major focus on muscle atrophy, adipose tissue wasting, anorexia and fatigue and updated the latest progress of pharmacological management of cancer cachexia, thereby further advancing the interventions that can counteract cancer cachexia.

Cisplatin-induced ototoxicity: Updates on molecular mechanisms and otoprotective strategies.

Cisplatin is a highly effective antitumor drug generally used in the treatment of solid malignant tumors. However, cisplatin causes severe side effects such as bone marrow depression, nephrotoxicity, and ototoxicity, thus limiting its clinical application. The incidence of ototoxicity induced by cisplatin ranges from 20% to 70%, and it usually manifests as a progressive, bilateral and irreversible hearing loss. Although the etiology of cisplatin-induced ototoxicity remains unclear, an increasing body of evidence suggests that the ototoxicity of cisplatin is mainly related to the production of reactive oxygen species and activation of apoptotic pathway in cochlear tissues. Many drugs have been well proved to protect cisplatin-induced hearing loss in vitro and in vivo. However, the anti-tumor effect of cisplatin is also weakened by systemic administration of those drugs for hearing protection, especially antioxidants. Therefore, establishing a local administration strategy contributes to the otoprotection without affecting the effect of cisplatin. This review introduces the pathology of ototoxicity caused by cisplatin, and focuses on recent developments in the mechanisms and protective strategies of cisplatin-induced ototoxicity.

Upregulation of Linc-ROR Promotes the Proliferation, Migration, and Invasion of Gastric Cancer Cells Through miR-212-3p/FGF7 Axis.

BACKGROUND: Linc-ROR is a long non-coding RNA, that is found aberrantly expressed in various human cancers. We aim here to unveil the role of Linc-ROR in gastric cancer (GC) progression. METHODS: qPCR was used to determine gene expression. Cell viability was measured by CCK-8 assay. Transwell assays were performed to evaluate the GC cells' migratory and invasive abilities. Xenograft mouse model was conducted to measure tumor growth. RESULTS: We found that Linc-ROR were overexpressed in GC tissues compared to the adjacent tissues. High Linc-ROR predicts poor prognosis of GC patients. The prediction of bioinformatics online revealed that Linc-ROR could bind to miR-212-3p. Further, dual-luciferase reporter assay confirmed a direct interaction between Linc-ROR and miR-212-3p. Overexpression of miR-212-3p facilitated GC cells' migration and invasion, while the silencing of miR-212-3p attenuated GC cell migratory and invasive abilities. Moreover, Linc-ROR knockdown significantly suppressed the proliferation, migration, and invasion of GC cells, whereas miR-212-3p antagomir partially reversed Linc-ROR knockdown-induced phenotypes. Fibroblast growth factor 7 (FGF7), a downstream molecule of miR-212-3p, was overexpressed in GC cells. The recovery of FGF7 expression partially reversed the phenotypes caused by Linc-ROR silencing. Mechanistically, silencing of Linc-ROR contributed to the downregulation of CDK4, CDK6, Cyclin D1, N-Cadherin, Vimentin, MMP-9, MMP-2, but caused the upregulation of P21, P27, E-Cadherin, CK-19 in MGC-803 cells; however, FGF7 treatment could reverse the results induced by Linc-ROR silencing. Results in vivo further suggested that Linc-ROR knockdown repressed GC tumor growth, where the expression of miR-212-3p was up-regulated and FGF7 expression was downregulated in tumor tissues of mice. CONCLUSION: These findings indicated that Linc-ROR/miR-212-3p/FGF7 axis played an important role in gastric cancer progression. Linc-ROR expression level was associated with the prognosis of GC patients.

ATF2 inhibits ani-tumor effects of BET inhibitor in a negative feedback manner by attenuating ferroptosis.

BET inhibitor (BETi) has potential therapeutic effects on human cancer especially in breast cancer. However, the detailed mechanisms remain unclear. Herein, we found that BETi JQ1 and I-BET-151 (I-BET) activated ATF2 through JNK1/2 pathway in breast cancer cells MDA-MB-231 (MB-231). In addition, overexpression of ATF2 blocked the reduction of cell viability induced by JQ1 or I-BET in breast cancer MB-231 and BT-549 cells, cervical cancer HeLa cells and lung cancer A549 cells. The induction of cell death by BETi was also attenuated by ATF2 in MB-231 and BT-549 cells. By contrast, depletion of ATF2 increased cancer cell sensitivity to BETi. In MB-231 cells xenograft model, ATF2 significantly inhibited the anti-tumor effects of JQ1. By detection of the oxidized form gluthione, malondialdehyde and lipid ROS, we showed that overexpression of ATF2 inhibited ferroptosis induced by BETi, whereas depletion of ATF2 promoted ferroptosis by BETi. Furthermore, the underlying mechanisms of ATF2-reduced ferroptosis were investigated. Overexpressed and depleted ATF2 were found to significantly upregulate and downregulate NRF2 protein and mRNA expression, respectively. The significantly positive correlations between NRF2 and ATF2 gene expression were found in breast, lung and cervical cancer tissues from TCGA database. In NRF2-depleted MB-231 cells, ATF2 failed to attenuate JQ1-stimulated ferroptosis. All these results suggested that ATF2 inhibited BETi-induced ferroptosis by increasing NRF2 expression. Altogether, our findings illustrated ATF2 suppressed ani-tumor effects of BETi in a negative feedback manner by attenuating ferroptosis. BETi combined with ATF2 or NRF2 inhibitor might be a novel strategy for treatment of human cancer.

Asiaticoside suppresses cell proliferation by inhibiting the NF­κB signaling pathway in colorectal cancer.

Colorectal cancer (CRC) is one of the leading causes of cancer­associated mortality. Asiaticoside (AC) exhibits antitumor effects; however, to the best of our knowledge, the biological function of AC in CRC cells remains unclear. Therefore, the aim of the present study was to investigate the effect of AC on CRC cells. In the present study, CCK­8 and colony formation assays were performed to assess the effects of AV on human CRC cell lines (HCT116, SW480 and LoVo). Mitochondrial membrane potential was examined by JC­1 staining. Cell apoptosis and cell cycle were monitored by flow cytometry, and the expression of genes was evaluated using RT­qPCR and western blot analysis. Furthermore, the biological effect of AC in vivo was detected using a xenograft mouse model. The findings revealed that 2 µM AC suppressed the proliferation of CRC cells in a time­ and dose­dependent manner, but had no adverse effects on normal human intestinal FHC cells at a range of concentrations. AC decreased the mitochondrial membrane potential and increased the apoptosis of CRC cells in a dose­dependent manner. Furthermore, AC induced cell cycle arrest at the G0/G1 phase. AC attenuated IκBα phosphorylation in a dose­dependent manner, thereby preventing P65 from entering the nucleus, and resulting in inhibition of the NF­κB signaling pathway. In addition, AC significantly reduced the expression of CDK4 and Cyclin D1 in a dose­dependent manner, significantly upregulated the activation of caspase­9 and caspase­3, and decreased the Bcl­2/Bax mRNA ratio. Furthermore, treatment with the NF­κB signaling pathway inhibitor JSH­23 significantly increased the cytotoxicity of AC in CRC cells. Findings of the xenograft mice model experiments revealed that AC significantly inhibited colorectal tumor growth in a dose­dependent manner. Overall, AC suppressed activation of the NF­κB signaling pathway by downregulating IκBα phosphorylation. This resulted in inhibition of CRC cell viability and an increase of cell apoptosis, which may form the basis of AC use in the treatment of patients with CRC.

Macrophages confer resistance to BET inhibition in triple-negative breast cancer by upregulating IKBKE.

BET inhibitors (BETi) exhibit a strong anti-tumor activity in triple-negative breast cancer (TNBC). However, BETi resistance has been reported in TNBC. The mechanisms of resistance have not been demonstrated. Tumor-associated macrophages (TAMs) are frequently involved in cancer cells resistance to chemotherapy, also associated with poor prognosis in TNBC. However, the role of TAMs in BETi resistance remains unknown. Here, we found that BETi JQ1 and I-BET151 exerted anti-tumor effects in TNBC by decreasing IKBKE expression to attenuate NF-κB signaling. TAMs have been reported to associate with chemoresistance in breast cancer. Here, we firstly found that TNBC-stimulated TAMs activated NF-κB signaling by upregulating IKBKE expression to enhance breast cancer cells resistance to BETi. The IKBKE levels were also proved to be higher in clinical TNBC tissues than Non-TNBC tissues, suggesting feedback induction of IKBKE expression by TNBC-stimulated TAMs in TNBC. Moreover, the induction of IKBKE by TAMs in TNBC cells was identified to be associated with STAT3 signaling, which was activated by TAM-secreted IL-6 and IL-10. Lastly, the combination of inhibitors of BET and STAT3 exerted a synergistic inhibition effects in TAM-cocultured or TAM CM-treated TNBC cells in vitro and in vivo. Altogether, our findings illustrated TNBC-activated macrophages conferred TNBC cells resistance to BETi via IL-6 or IL-10/STAT3/IKBKE/NF-κB axis. Blockade of IKBKE or double inhibition of BET and STAT3 might be a novel strategy for treatment of TNBC.

NR5A2 synergizes with NCOA3 to induce breast cancer resistance to BET inhibitor by upregulating NRF2 to attenuate ferroptosis.

BET inhibitors (BETi) exert an excellent anti-cancer activity in breast cancer. However, the identification of new potential targets to enhance breast cancer sensitivity to BETi is still an enormous challenge. Both NR5A2 and NCOA3 are frequently involved in cancer cells resistance to chemotherapy, also associated with poor prognosis in breast cancer. However, the functions of NR5A2 and NCOA3 in BETi resistance remains unknown. In this study, we found that BETi JQ1 and I-BET151 exhibited anti-cancer effects in breast cancer by inducing ferroptosis. NCOA3 as a coactivator synergized with NR5A2 to prevent BETi-induced ferroptosis. Mechanistically, we identified NR5A2 synergized with NCOA3 to increase expression of NRF2, a transcription factor that controls the expression of many antioxidant genes. Moreover, inhibition of NR5A2 or NCOA3 using small molecule inhibitors enhanced anti-cancer effects of BETi against breast cancer in vivo and in vitro. Altogether, our findings illustrated NR5A2 synergized with NCOA3 to confer breast cancer cells resistance to BETi by induction of NRF2. Inhibition of NR5A2/NCOA3 combined with BETi might be a novel strategy for treatment of breast cancer.

Inhibition of esophageal-carcinoma cell proliferation by genistein via suppression of JAK1/2-STAT3 and AKT/MDM2/p53 signaling pathways.

Esophageal carcinoma (EsC) is a clinically challenging neoplastic disease. Genistein, a natural isoflavone product, has anti-tumor properties. Through in vitro and in vivo studies, we found that genistein suppressed EsC cell proliferation in a time- and concentration-dependent manner. In addition, genistein markedly promoted apoptosis and arrested cell cycle at the G0/G1 phase in a concentration-dependent manner. Furthermore, high concentrations of genistein have no adverse effect on normal esophageal epithelial cells. Mechanistically, genistein treatment strikingly reduced the expression of cell cycle-associated genes, and up-regulated the expression of cell apoptosis-related genes in EsC cells. Additionally, genistein dramatically decreased epidermal growth factor receptor (EGFR) expression and attenuated its down-stream signaling molecules STAT3, MDM2, Akt and JAK1/2 phosphorylation, resulting in inhibited nuclear translocation of STAT3 and MDM2, thereby inhibiting the JAK1/2-STAT3 and AKT/MDM2/p53 signaling pathways. In xenograft nude mice, genistein administration strikingly impaired tumor growth in a dose-dependent manner. Moreover, similar disturbances in molecular mechanisms were observed in vivo. Taken together, genistein suppressed the JAK1/2-STAT3 and AKT/MDM2/p53 signaling pathways by decreasing EGFR expression, leading to cell apoptosis, cell cycle arrest, and proliferation inhibition in EsC cells. Our findings suggest that genistein may be a promising alternative adjuvant therapy for patients with EsC.

microRNA-499a promotes the progression and chemoresistance of cervical cancer cells by targeting SOX6.

Emerging evidence has indicated that microRNAs are involved in multiple processes of cancer development. Previous studies have demonstrated that microRNA-499a (miR-499a) plays both oncogenic and tumor suppressive roles in several types of malignancies, and genetic variants in miR-499a are associated with the risk of cervical cancer. However, the biological roles of miR-499a in cervical cancer have not been investigated. Quantitative real-time PCR was used to assess miR-499a expression in cervical cancer cells. Mimics or inhibitor of miR-499a was transfected into cervical cancer cells to upregulate or downregulate miR-499a expression. The effects of miR-499a expression change on cervical cancer cells proliferation, colony formation, tumorigenesis, chemosensitivity, transwell migration and invasion were assessed. The potential targets of miR-499a were predicted using online database tools and validated using real-time PCR, Western blot and luciferase reporter experiments. miR-499a was significantly upregulated in cervical cancer cells. Moreover, overexpression of miR-499a significantly enhanced the proliferation, cell cycle progression, colony formation, apoptosis resistance, migration and invasion of cervical cancer cells, while inhibiting miR-499a showed the opposite effects. Further exploration demonstrated that Sex-determining region Y box 6 was the direct target of miR-499a. miR-499a-induced SOX6 downregulation mediated the oncogenic effects of miR-499a in cervical cancer. Inhibiting miR-499a could enhance the anticancer effects of cisplatin in the xenograft mouse model of cervical cancer. Our findings for the first time suggest that miRNA-499a may play an important role in the development of cervical cancer and could serve as a potential therapeutic target.

Dihydroartemisinin-induced unfolded protein response feedback attenuates ferroptosis via PERK/ATF4/HSPA5 pathway in glioma cells.

BACKGROUND: Dihydroartemisinin (DHA) has been shown to exert anticancer activity through iron-dependent reactive oxygen species (ROS) generation, which is similar to ferroptosis, a novel form of cell death. However, whether DHA causes ferroptosis in glioma cells and the potential regulatory mechanisms remain unclear. METHODS: Effects of DHA on the proliferation, cell death, ROS and lipid ROS generation as well as reduced gluthione consumption were assessed in glioma cells with or without ferroptosis inhibitor. The biological mechanisms by which glioma cells attenuate the pro-ferroptotic effects of DHA were assessed using molecular methods. RESULTS: DHA induced ferroptosis in glioma cells, as characterized by iron-dependent cell death accompanied with ROS generation and lipid peroxidation. However, DHA treatment simultaneously activated a feedback pathway of ferroptosis by increasing the expression of heat shock protein family A (Hsp70) member 5 (HSPA5). Mechanistically, DHA caused endoplasmic reticulum (ER) stress in glioma cells, which resulted in the induction of HSPA5 expression by protein kinase R-like ER kinase (PERK)-upregulated activating transcription factor 4 (ATF4). Subsequent HSPA5 upregulation increased the expression and activity of glutathione peroxidase 4 (GPX4), which neutralized DHA-induced lipid peroxidation and thus protected glioma cells from ferroptosis. Inhibition of the PERK-ATF4-HSPA5-GPX4 pathway using siRNA or small molecules increased DHA sensitivity of glioma cells by increasing ferroptosis both in vitro and in vivo. CONCLUSIONS: Collectively, these data suggested that ferroptosis might be a novel anticancer mechanism of DHA in glioma and HSPA5 may serve as a negative regulator of DHA-induced ferroptosis. Therefore, inhibiting the negative feedback pathway would be a promising therapeutic strategy to strengthen the anti-glioma activity of DHA.

Higher plasma concentration of TP53-induced glycolysis and apoptosis regulator is associated with a lower risk of colorectal cancer metastasis.

PURPOSE: We aimed to explore the association of plasma TP53-induced glycolysis and apoptosis regulator (TIGAR) level with colorectal cancer (CRC) metastasis. METHODS: A cross-sectional study of 126 CRC patients was conducted in Xiamen, China. Multivariable logistic regression was used to calculate adjusted OR and 95% CIs of plasma TIGAR concentration for CRC metastasis in different models with adjustment for potential confounders. Area under the curve (AUC) of receiver operating characteristic (ROC) curve was used to evaluate the diagnostic value. RESULTS: CRC patients with metastasis showed significantly decreased plasma TIGAR concentration compared to their controls (1.97±0.64 vs 2.49±0.69 ng/mL [log transformed], P=0.002). Higher plasma TIGAR was significantly associated with the decreased risk of CRC metastasis, and the adjusted OR (95% CI) was 0.134 (0.027-0.676, P=0.015) for per SD increase in plasma TIGAR concentration, and the trend test for increasing tertiles showed a negative trend of plasma TIGAR on risk of CRC metastasis (P for trend test: 0.005). Pearson correlation coefficients of plasma TIGAR with other cancer biomarkers (carbohydrate antigen 50 [CA50], carbohydrate antigen 199 [CA199], carbohydrate antigen 125 [CA125], carbohydrate antigen 724 [CA724], carcinoembryonic antigen [CEA], and ferritin [FER]) was low (P>0.05). AUC (95% CI) of ROC curve of plasma TIGAR for CRC metastasis was comparable to the values of cancer biomarkers (all P-values <0.05). CONCLUSION: Higher level of plasma TIGAR was significantly and independently associated with lower risk of CRC metastasis, and its prognostic value on CRC metastasis was comparable to the common cancer biomarkers.