Elucidating the Role of Let-7d-5p and OLR1 in the Progression and Prognosis of Oral Squamous Cell Carcinoma via FAK/P53 Signaling Axis.

BACKGROUND/AIM: Despite advances in oral squamous cell carcinoma (OSCC) diagnosis and treatment, the five-year survival rate remains low, underscoring the need for improved biomarkers and therapeutic strategies. This study investigated the role of let-7d-5p microRNA (miRNA) and its target gene OLR1 in OSCC, focusing on their implications in tumor progression, metastasis and potential as therapeutic targets. MATERIALS AND METHODS: Employing next-generation sequencing and bioinformatic tools, we profiled differentially expressed miRNAs in metastatic OSCC cell lines, identifying let-7d-5p as a key down-regulated miRNA and OLR1 as a novel target of let-7d-5p. We validated this interaction using luciferase reporter assays and studied the biological effects of modulating let-7d-5p and OLR1 expression on OSCC cell proliferation, migration, invasion, and stemness. Additionally, we analyzed clinical data to establish the relevance of OLR1 expression in OSCC prognosis. RESULTS: Our findings revealed let-7d-5p as a potent suppressor of OSCC metastasis, primarily by targeting and down-regulating OLR1. OLR1-silencing reduced OSCC cell invasiveness, migration, and stemness, indicating its prominent role in tumor progression. Mechanistically, let-7d-5p modulates a signaling cascade involving FAK, SRC, PAXILLIN, and p53, influencing cellular apoptosis and chemoresistance. Clinically, elevated OLR1 expression significantly correlates with advanced OSCC stages and poorer survival rates, highlighting its potential as a prognostic marker and therapeutic target. CONCLUSION: Our study uncovers the significance of the let-7d-5p-OLR1 axis in OSCC pathogenesis, offering novel insights for future therapeutic interventions.

The role of vestibular function tests in nontuberculous mycobacterial otomastoiditis: A case report.

BACKGROUND: Nontuberculous mycobacteria (NTM), an extremely rare pathogen causing cervicofacial infections, may result in permanent hearing impairment or intracranial complications. Due to the lack of specific manifestations during the initial onset of NTM otomastoiditis, physicians may misdiagnose it as cholesteatoma or other common bacterial infections. PATIENT CONCERNS: A 44-year-old male who complained of left-sided aural fullness, otalgia, and dizziness for 2 months. DIAGNOSIS: The initial diagnosis was hypothesized to be cholesteatoma based on a whitish mass with mucoid discharge filling the entire outer ear canal on otoscopy and left-sided mixed hearing loss. However, NTM was identified by microbial culture at the 2-month follow-up after surgery. INTERVENTIONS: The patient underwent a left-sided exploratory tympanotomy. Because NTM otomastoiditis was diagnosed, 3 weeks of starting therapies were administered with azithromycin (500 mg/day, oral administration), cefoxitin (3 g/day, intravenous drip), and amikacin (750 mg/day, intravenous drip). The maintenance therapies were azithromycin (500 mg/day, oral administration) and doxycycline (200 mg/day, oral administration) for 7 months. OUTCOMES: The patient's clinical condition improved initially after surgery, but the otomastoiditis gradually worsened, combined with subtle meningitis, 2 months after surgery. The external auditory canal became swollen and obstructed, making it difficult to monitor the treatment efficacy through otoscopy. Thus, we used regular vestibular function tests, including static posturography, cervical vestibular evoked myogenic potentials, and video Head Impulse Test, to assess recovery outcomes. After antibiotic treatment, the infectious symptoms subsided significantly, and there was no evidence of infection recurrence 7 months after treatment. Improvements in static posturography and cervical vestibular evoked myogenic potentials were compatible with the clinical manifestations, but video Head Impulse Test showed an unremarkable correlation. LESSONS: The clinical condition of NTM otomastoiditis may be evaluated using vestibular tests if patients have symptoms of dizziness.

The prevalence of obstructive sleep apnea syndrome after COVID-19 infection.

Obstructive sleep apnea is a well-known risk factor regarding the severity of COVID-19 infection. However, to date, relatively little research performed on the prevalence of obstructive sleep apnea in COVID-19 survivors. The purpose of this study was to investigate the risk of obstructive sleep apnea after COVID-19 infection. This study was based on data collected from the US Collaborative Network in TriNetX. From January 1, 2020 to June 30, 2022, participants who underwent the SARS-CoV-2 test were included in the study. Based on their positive or negative results of the COVID-19 test results (the polymerase chain reaction [PCR] test), we divided the study population into two groups. The duration of follow-up began when the PCR test was administered and continued for 12 months. Hazard ratios (HRs) and 95% confidence intervals (CIs) for newly recorded COVID-19 positive subjects for obstructive sleep apnea were calculated using the Cox proportional hazards model and compared to those without COVID-19 infection. Subgroup analyses were performed for the age, sex, and race, groups. The COVID-19 group was associated with an increased risk of obstructive sleep apnea, at both 3 months of follow-up (HR: 1.51, 95% CI: 1.48-1.54), and 1 year of follow-up (HR: 1.57, 95% CI: 1.55-1.60). Kaplan-Meier curves regarding the risk of obstructive sleep apnea revealed a significant difference of probability between the two cohorts in the follow-up periods of 3 months and 1 year (Log-Rank test, p < 0.001). The risks of obstructive sleep apnea among COVID-19 patients were significant in the less than 65 year of age group (HR: 1.50, 95% CI: 1.47-1.52), as well as in the group older than or equal to 65 years (HR:1.69, 95% CI: 1.64-1.73). Furthermore, the risks of obstructive sleep apnea were evident in both the male and female COVID-19 groups. Compared to the control group, the risks of obstructive sleep apnea in the COVID-19 participants increased in the subgroups of White (HR: 1.62, 95% CI: 1.59-1.64), Blacks/African Americans (HR: 1.50, 95% CI: 1.45-1.55), Asian (HR: 1.46, 95% CI: 1.32-1.62) and American Indian/Alaska Native (HR: 1.36, 95% CI: 1.07-1.74). In conclusion, the incidence of new diagnosis obstructive sleep apnea could be substantially higher after COVID-19 infection than non-COVID-19 comparison group. Physicians should evaluate obstructive sleep apnea in patients after COVID-19 infection to help prevent future long-term adverse effects from occurring in the future, including cardiovascular and neurovascular disease.

AIM2 promotes irradiation resistance, migration ability and PD-L1 expression through STAT1/NF-κB activation in oral squamous cell carcinoma.

BACKGROUND: Radioresistance and lymph node metastasis are common phenotypes of refractory oral squamous cell carcinoma (OSCC). As a result, understanding the mechanism for radioresistance and metastatic progression is urgently needed for the precise management of refractory OSCC. Recently, immunotherapies, e.g. immune checkpoint inhibitors (ICIs), were employed to treat refractory OSCC; however, the lack of predictive biomarkers still limited their therapeutic effectiveness. METHODS: The Cancer Genome Atlas (TCGA)/Gene Expression Omnibus (GEO) databases and RT-PCR analysis were used to determine absent in melanoma 2 (AIM2) expression in OSCC samples. Colony-forming assay and trans-well cultivation was established for estimating AIM2 function in modulating the irradiation resistance and migration ability of OSCC cells, respectively. RT-PCR, Western blot and flow-cytometric analyses were performed to examine AIM2 effects on the expression of programmed death-ligand 1 (PD-L1) expression. Luciferase-based reporter assay and site-directed mutagenesis were employed to determine the transcriptional regulatory activity of Signal Transducer and Activator of Transcription 1 (STAT1) and NF-κB towards the AIM2-triggered PD-L1 expression. RESULTS: Here, we found that AIM2 is extensively upregulated in primary tumors compared to the normal adjacent tissues and acts as a poor prognostic marker in OSCC. AIM2 knockdown mitigated, but overexpression promoted, radioresistance, migration and PD-L1 expression via modulating the activity of STAT1/NF-κB in OSCC cell variants. AIM2 upregulation significantly predicted a favorable response in patients receiving ICI treatments. CONCLUSIONS: Our data unveil AIM2 as a critical factor for promoting radioresistance, metastasis and PD-L1 expression and as a potential biomarker for predicting ICI effectiveness on the refractory OSCC.

Guanylate binding protein 5 triggers NF-κB activation to foster radioresistance, metastatic progression and PD-L1 expression in oral squamous cell carcinoma.

Radioresistance and metastasis are critical issues in managing oral squamous cell carcinoma (OSCC). Although immune checkpoint inhibitors (ICIs) has been recommended to treat OSCC, lacking useful biomarkers limited their anti-cancer effectiveness. We found that guanylate binding protein 5 (GBP5) is upregulated in primary tumors and associates with radioresistance in OSCC. GBP5 expression causally associated with cellular radioresistance and migration ability in the OSCC cell variants. GBP5 upregulation was examined to be correlated with NF-κB activation and programmed cell death-ligand 1 (PD-L1) elevation in OSCC samples. GBP5 knockdown was mitigated, but overexpression enhanced, NF-κB activity and PD-L1 expression in the OSCC cells. NF-κB inhibition by SN50 dramatically suppressed the GBP5-forested irradiation resistance, cellular migration ability and PD-L1 expression in OSCC cells. Importantly, GBP5 upregulation predicted a favorable outcome in cancer patients received ICI treatment. Our findings provide GBP5 as a useful biomarker to predict the anti-OSCC effectiveness of irradiation and ICIs.

NEDD8 promotes radioresistance via triggering autophagy formation and serves as a novel prognostic marker in oral squamous cell carcinoma.

BACKGROUND: Radiotherapy is the first-line regimen for treating oral squamous cell carcinoma (OSCC) in current clinics. However, the development of therapeutic resistance impacts the anticancer efficacy of irradiation in a subpopulation of OSCC patients. As a result, discovering a valuable biomarker to predict radiotherapeutic effectiveness and uncovering the molecular mechanism for radioresistance are clinical issues in OSCC. METHODS: Three OSCC cohorts from The Cancer Genome Atlas (TCGA), GSE42743 dataset and Taipei Medical University Biobank were enrolled to examine the transcriptional levels and prognostic significance of neuronal precursor cell-expressed developmentally downregulated protein 8 (NEDD8). Gene set enrichment analysis (GSEA) was utilized to predict the critical pathways underlying radioresistance in OSCC. The colony-forming assay was used to estimate the consequences of irradiation sensitivity after the inhibition or activation of the NEDD8-autophagy axis in OSCC cells. RESULTS: NEDD8 upregulation was extensively found in primary tumors compared to normal adjacent tissues and potentially served as a predictive marker for the therapeutic effectiveness of irradiation in OSCC patients. NEDD8 knockdown enhanced radiosensitivity but NEDD8 overexpression reduced it in OSCC cell lines. The inclusion of MLN4924, a pharmaceutical inhibitor for NEDD8-activating enzyme, dose-dependently restored the cellular sensitivity to irradiation treatment in irradiation-insensitive OSCC cells. Computational simulation by GSEA software and cell-based analyses revealed that NEDD8 upregulation suppresses Akt/mTOR activity to initiate autophagy formation and ultimately confers radioresistance to OSCC cells. CONCLUSION: These findings not only identify NEDD8 as a valuable biomarker to predict the efficacy of irradiation but also offer a novel strategy to overcome radioresistance via targeting NEDD8-mediated protein neddylation in OSCC.

AIM2 upregulation promotes metastatic progression and PD-L1 expression in lung adenocarcinoma.

Cancer metastasis leading to the dysfunction of invaded organs is the main cause of the reduced survival rates in lung cancer patients. However, the molecular mechanism for lung cancer metastasis remains unclear. Recently, the increased activity of inflammasome appeared to correlate with the metastatic progression and immunosuppressive ability of various cancer types. Our results showed that the mRNA levels of absence in melanoma 2 (AIM2), one of the inflammasome members, are extensively upregulated in primary tumors compared with normal tissues derived from the TCGA lung adenocarcinoma (LUAD) database. Moreover, Kaplan-Meier analysis demonstrated that a higher mRNA level of AIM2 refers to a poor prognosis in LUAD patients. Particularly, AIM2 upregulation is closely correlated with smoking history and the absence of EGFR/KRAS/ALK mutations in LUAD. We further showed that the endogenous mRNA levels of AIM2 are causally associated with the metastatic potentials of the tested LUAD cell lines. AIM2 knockdown suppressed but overexpression promoted the migration ability and lung colony-forming ability of tested LUAD cells. In addition, we found that AIM2 upregulation is closely associated with an increased level of immune checkpoint gene set, as well as programmed cell death-ligand 1 (PD-L1) transcript, in TCGA LUAD samples. AIM2 knockdown predominantly repressed but overexpression enhanced PD-L1 expression via altering the activity of PD-L1 transcriptional regulators NF-κB/STAT1 in LUAD cells. Our results not only provide a possible mechanism underlying the AIM2-promoted metastatic progression and immune evasion of LUAD but also offer a new strategy for combating metastatic/immunosuppressive LUAD via targeting AIM2 activity.

Lactotransferrin Downregulation Serves as a Potential Predictor for the Therapeutic Effectiveness of mTOR Inhibitors in the Metastatic Clear Cell Renal Cell Carcinoma without PTEN Mutation.

Approximately 30% of clear cell renal cell carcinoma (ccRCC) patients develop metastatic spread at the first diagnosis. Therefore, identifying a useful biomarker to predict ccRCC metastasis or therapeutic effectiveness in ccRCC patients is urgently needed. Previously, we demonstrated that lactotransferrin (LTF) downregulation enhanced the metastatic potential of ccRCC. Here, we show that LTF expression conversely associates with the mTORC1 activity as simulated by gene set enrichment analysis (GSEA). Moreover, Western blot analyses revealed that the LTF knockdown promoted, but the inclusion of recombinant human LTF protein suppressed, the phosphorylation of Akt/mTOR proteins in the detected ccRCC cells. Kaplan-Meier analyses demonstrated that the signature of combining an upregulated mTORC1 activity with a downregulated LTF expression referred to a worse overall and progression-free survival probabilities and associated with distant cancer metastasis in TCGA ccRCC patients. Furthermore, we found that the LTF-suppressed Akt/mTOR activation triggered an increased formation of autophagy in the highly metastatic ccRCC cells. The addition of autophagy inhibitor 3-methyadenine restored the LTF-suppressed cellular migration ability of highly metastatic ccRCC cells. Receiver operating characteristic (ROC) analyses showed that the expression of the LTF and MTORC1 gene set, not the autophagy gene set, could be the useful biomarkers to predict 5-year overall survival rate and cancer progression in ccRCC patients. Significantly, the signature of combining mTORC1 upregulation and LTF downregulation was shown as an independent prognostic factor in a multivariate analysis under the progression-free survival condition using the TCGA ccRCC database. Finally, the treatment with mTOR inhibitor rapamycin predominantly reduced the formation of autophagy and ultimately mitigated the cellular migration ability of ccRCC cells with LTF knockdown. Our findings suggest that LTF downregulation is a biomarker for guiding the use of mTOR inhibitors to combat metastatic ccRCC in the clinic.

Novel strategy for food safety risk management and communication: Risk identification for benzoic acid residues in pickled vegetables.

Benzoic acid (BA) is widely used as an antimicrobial preservative to prolong the shelf-life of pickled vegetables. A method for rapidly determining the BA content in forty pickled vegetable samples was developed by coupling ultrasonic extraction with surface-enhanced Raman scattering (SERS) and an adaptive iteratively reweighted penalized least-squares (AirPLS) algorithm. The results obtained with this method were compared and correlated with those from high-performance liquid chromatography measurements. Amplification of the Raman scattering via the SERS effect was induced by gold nanoparticles (AuNPs) when BA was irradiated with a 785 nm laser. The AirPLS algorithm was used to reduce the background interference signal, which was also amplified. The amplified Raman scattering effect of BA in the pickled vegetables displayed a positive and significant correlation with the HPLC concentration of BA, with high reproducibility. For HPLC determination of the concentration of BA in the range of 0-820 ppm, the BA monomer's intensity of the 944-1,005 cm-1 and 1,366-1,373 cm-1 peaks, and BA dimer's intensity of the 1,025 cm-1 and 1,465-1,482 cm-1 peaks in the SERS spectrum were respectively converted to the Z-ratio BA monomer and Z-ratio BA dimer standard scores by Z-Score conversion. The sum's (Z-ratio BA monomer + Z-ratio BA dimer) sensitivity was 100%, and specificity was 90.9% by receiver operating characteristic curve. This study found that a Raman spectroscopy-based monitoring method can be one of the fastest screening inspection options that can complete an analysis within a short period of time and produce reliable results. This approach is particularly cost-effective, which makes it suitable for the initial screening of raw materials and provides an effective management strategy easy to communicate with food safety officials.

DNA polymerase theta repression enhances the docetaxel responsiveness in metastatic castration-resistant prostate cancer.

OBJECTIVE: Docetaxel remains a main treatment for metastatic castration-resistant prostate cancer (mCRPC); however, the development of docetaxel resistance has been found in some mCRPC patients. The aim of this work is to identify an effective biomarker for predicting therapeutic effectiveness of docetaxel in mCRPC patients. METHODS: We examined DNA polymerase theta (POLQ) expression in The Cancer Genome Atlas (TCGA) database and Tissue microarray. Kaplan-Meier analyses were performed to estimate the prognostic significance of POLQ. A series of functional analyses were conducted in cell lines and xenograft models. Regulated pathways were predicted by Geneset Enrichment Analysis (GSEA) software and further investigated by luciferase reporter and RT-PCR assays. RESULTS: We found that POLQ mRNA levels in CRPC tissues was significantly higher than that of other DNA polymerases in non-CRPC prostate tissues. POLQ upregulation was extensively detected in mCRPC and strongly predicted a poor prognosis. POLQ knockdown enhanced docetaxel sensitivity in a cell-based cytotoxicity assay and promoted the therapeutic effect on the tumor growth of metastatic PC-3M cells in xenograft models. The computational simulation by GSEA software significantly predicted the association between POLQ upregulation and the activation of E2F/G2M checkpoint-related pathways. Moreover, luciferase reporter and RT-PCR assays demonstrated that POLQ knockdown downregulated the transcriptional regulatory activity of E2F and repressed E2F/G2M checkpoint-regulated CDK1 in mCRPC cells. CONCLUSION: Our results suggest that POLQ serves as a predictive factor for poor docetaxel response and provide a novel strategy to enhance the anticancer effects of docetaxel therapy by targeting POLQ in mCRPC patients.

Erratum: Lee, H.H., et al. Histone 2A Family Member J Drives Mesenchymal Transition and Temozolomide Resistance in Glioblastoma Multiforme. Cancers 2020, 12, 98.

The authors wish to make the following changes to this paper [...].

FOXD1 Repression Potentiates Radiation Effectiveness by Downregulating G3BP2 Expression and Promoting the Activation of TXNIP-Related Pathways in Oral Cancer.

Radiotherapy is commonly used to treat oral cancer patients in the current clinics; however, a subpopulation of patients shows poor radiosensitivity. Therefore, the aim of this study is to identify a biomarker or druggable target to enhance the effectiveness of radiotherapy on oral cancer patients. By performing an in silico analysis against public databases, we found that the upregulation of FOXD1, a gene encoding forkhead box d1 (Foxd1), is extensively detected in primary tumors compared to normal tissues and associated with a poor outcome in oral cancer patients receiving irradiation treatment. Moreover, our data showed that the level of FOXD1 transcript is causally relevant to the effective dosage of irradiation in a panel of oral cancer cell lines. The FOXD1 knockdown (FOXD1-KD) dramatically suppressed the colony-forming ability of oral cancer cells after irradiation treatment. Differentially expressed genes analysis showed that G3BP2, a negative regulator of p53, is predominantly repressed after FOXD1-KD and transcriptionally regulated by Foxd1, as judged by a luciferase-based promoter assay in oral cancer cells. Gene set enrichment analysis significantly predicted the inhibition of E2F-related signaling pathway but the activation of the interferons (IFNs) and p53-associated cellular functions, which were further validated by luciferase reporter assays in the FOXD1-KD oral cancer cells. Robustly, our data showed that FOXD1-KD fosters the expression of TXNIP, a downstream effector of IFN signaling and activator of p53, in oral cancer cells. These findings suggest that FOXD1 targeting might potentiate the anti-cancer effectiveness of radiotherapy and promote immune surveillance on oral cancer.

TNFSF13 upregulation confers chemotherapeutic resistance via triggering autophagy initiation in triple-negative breast cancer.

Since chemotherapy is a main strategy to treat triple-negative breast cancer (TNBC) patients currently, identifying a biomarker to predict chemotherapeutic responses is urgently needed for patients to avoid suffering through unnecessary chemotherapeutic treatments. Here, we found that the endogenous expression of TNFSF13 in a panel of TNBC cell lines highly correlates with paclitaxel (PTX) and doxorubicin IC50 concentrations. Whereas knocking down TNFSF13 enhances PTX effectiveness in PTX-insensitive MDA-MB231 cells, recombinant TNFSF13 (recTNFSF13) desensitizes PTX-sensitive HCC1806 cells to PTX treatment. Moreover, Kaplan-Meier analysis revealed that higher TNFSF13 mRNA expression significantly predicts an increased risk for cancer recurrence in estrogen receptor (ER)-negative breast cancer patients receiving an anthracycline-based treatment. Accordingly, immunohistochemistry experiments indicated that higher levels of TNFSF13 protein are detected in TNBC patients who do not respond to an anthracycline-based treatment. The in silico analysis and Western blotting demonstrated that TNFSF13 expression inversely associates with the activity of the Akt-mTOR pathway, which acts as a negative regulator of autophagy activity. Significantly, the pharmaceutical inhibition of autophagy activity restores the therapeutic effectiveness of PTX in TNFSF13-treated HCC1806 cells. These findings suggest that TNFSF13 can serve as a predictive biomarker for TNBC patients, who can use it to decide whether to receive chemotherapy. KEY MESSAGES: TNFSF13 upregulation correlates with a poor response to chemotherapy in TNBCs. TNFSF13 promotes autophagy initiation in chemotherapeutic resistant TNBCs. Therapeutic targeting of autophagy initiation overcomes the TNFSF13-related chemoresistance. TNFSF13 could be a predictive biomarker for TNBC patients receiving chemotherapy.

The Gαh/phospholipase C-δ1 interaction promotes autophagosome degradation by activating the Akt/mTORC1 pathway in metastatic triple-negative breast cancer.

Lung metastasis (LM) is commonly found in triple-negative breast cancer (TNBC); however, the molecular mechanism underlying TNBC metastasis to lungs remains largely unknown. We thus aimed to uncover a possible mechanism for the LM of TNBC. Here we show that the phosphorylation of Akt and mTORC1 was positively but the autophagy activity was negatively correlated with endogenous Gαh levels and cell invasion ability in TNBC cell lines. Whereas the knockdown of Gαh, as well as blocking its binding with PLC-δ1 by a synthetic peptide inhibitor, in the highly invasive MDA-MB231 cells dramatically suppressed Akt/mTORC1 phosphorylation and blocked autophagosome degradation, the overexpression of Gαh in the poorly invasive HCC1806 cells enhanced Akt/mTORC1 phosphorylation but promoted autophagosome degradation. The pharmaceutical inhibition of autophagy initiation by 3-methyladenine was found to rescue the cell invasion ability and LM potential of Gαh-silenced MDA-MB231 cells. In contrast, the inhibition of mTORC1 activity by rapamycin suppressed autophagosome degradation but mitigated the cell invasion ability and LM potential of Gαh-overexpressing HCC1806 cells. These findings demonstrate that the induction of autophagy activity or the inhibition of Akt-mTORC1 axis provides a useful strategy to combat the Gαh/PLC-δ1-driven LM of TNBC.

IMPA2 Downregulation Enhances mTORC1 Activity and Restrains Autophagy Initiation in Metastatic Clear Cell Renal Cell Carcinoma.

Although mTOR inhibitors have been approved as first-line therapy for treating metastatic clear cell renal cell carcinoma (ccRCC), the lack of useful markers reduces their therapeutic effectiveness. The objective of this study was to estimate if inositol monophosphatase 2 (IMPA2) downregulation refers to a favorable outcome in metastatic ccRCC receiving mTOR inhibitor treatment. Gene set enrichment analysis predicted a significant activation of mTORC1 in the metastatic ccRCC with IMPA2 downregulation. Transcriptional profiling of IMPA2 and mTORC1-related gene set revealed significantly inverse correlation in ccRCC tissues. Whereas the enforced expression of exogenous IMPA2 inhibited the phosphorylation of Akt/mTORC1, artificially silencing IMPA2 led to increased phosphorylation of Akt/mTORC1 in ccRCC cells. The pharmaceutical inhibition of mTORC1 activity by rapamycin reinforced autophagy initiation but suppressed the cellular migration and lung metastatic abilities of IMPA2-silenced ccRCC cells. In contrast, blocking autophagosome formation with 3-methyladenine rescued the mitigated metastatic potential in vitro and in vivo in IMPA2-overexpressing ccRCC cells. Our findings indicated that IMPA2 downregulation negatively activates mTORC1 activity and could be a biomarker for guiding the use of mTOR inhibitors or autophagy inducers to combat metastatic ccRCC in the clinic.

Nicotinic Acetylcholine Receptor Subunit Alpha-5 Promotes Radioresistance via Recruiting E2F Activity in Oral Squamous Cell Carcinoma.

Radiotherapy is commonly used to treat patients with oral squamous cell carcinoma (OSCC), but a subpopulation of OSCC patients shows a poor response to irradiation treatment. Therefore, identifying a biomarker to predict the effectiveness of radiotherapy in OSCC patients is urgently needed. In silico analysis of public databases revealed that upregulation of CHRNA5, the gene encoding nicotinic acetylcholine receptor subunit alpha-5, is extensively detected in primary tumors compared to normal tissues and predicts poor prognosis in OSCC patients. Moreover, CHRNA5 transcript level was causally associated with the effective dose of irradiation in a panel of OSCC cell lines. Artificial silencing of CHRNA5 expression enhanced, but nicotine reduced, the radiosensitivity of OSCC cells. Gene set enrichment analysis demonstrated that the E2F signaling pathway is highly activated in OSCC tissues with high levels of CHRNA5 and in those derived from patients with cancer recurrence after radiotherapy. CHRNA5 knockdown predominantly suppressed E2F activity and decreased the phosphorylation of the Rb protein; however, nicotine treatment dramatically promoted E2F activity and increased Rb phosphorylation, which was mitigated after CHRNA5 knockdown in OSCC cells. Notably, the signature combining increased mRNA levels of CHRNA5 and the E2F signaling gene set was associated with worse recurrence-free survival probability in OSCC patients recorded to be receiving radiotherapy. Our findings suggest that CHRNA5 is not only a useful biomarker for predicting the effectiveness of radiotherapy but also a druggable target to enhance the cancericidal effect of irradiation on OSCC.

Histone 2A Family Member J Drives Mesenchymal Transition and Temozolomide Resistance in Glioblastoma Multiforme.

Glioblastoma multiforme (GBM) is the most aggressive brain tumor and has a poor prognosis and is poorly sensitive to radiotherapy or temozolomide (TMZ) chemotherapy. Therefore, identifying new biomarkers to predict therapeutic responses of GBM is urgently needed. By using The Cancer Genome Atlas (TCGA) database, we found that the upregulation of histone 2A family member J (H2AFJ), but not other H2AFs, is extensively detected in the therapeutic-insensitive mesenchymal, IDH wildtype, MGMT unmethylated, or non-G-CIMP GBM and is associated with poor TMZ responsiveness independent of radiation. Similar views were also found in GBM cell lines. Whereas H2AFJ knockdown diminished TMZ resistance, H2AFJ overexpression promoted TMZ resistance in a panel of GBM cell lines. Gene set enrichment analysis (GSEA) revealed that H2AFJ upregulation accompanied by the activation of TNF-α/NF-κB and IL-6/STAT3-related pathways is highly predicted. Luciferase-based promoter activity assay further validated that the activities of NF-κB and STAT3 are causally affected by H2AFJ expression in GBM cells. Moreover, we found that therapeutic targeting HADC3 by tacedinaline or NF-κB by ML029 is likely able to overcome the TMZ resistance in GBM cells with H2AFJ upregulation. Significantly, the GBM cohorts harboring a high-level H2AFJ transcript combined with high-level expression of TNF-α/NF-κB geneset, IL-6/STAT3 geneset or HADC3 were associated with a shorter time to tumor repopulation after initial treatment with TMZ. These findings not only provide H2AFJ as a biomarker to predict TMZ therapeutic effectiveness but also suggest a new strategy to combat TMZ-insensitive GBM by targeting the interaction network constructed by TNF-α/NF-κB, IL-6/STAT3, HDAC3, and H2AFJ.

FBXL7 Upregulation Predicts a Poor Prognosis and Associates with a Possible Mechanism for Paclitaxel Resistance in Ovarian Cancer.

Paclitaxel (PTX) is a common regimen used to treat patients with ovarian cancer. Although approximately 60% of ovarian cancer patients exhibit a pathologic complete response (pCR), approximately 40% of patients appear to be insensitive to PTX adjuvant therapy. Thus, identifying a useful biomarker to predict pCR would be of great help to ovarian cancer patients who decide to receive PTX treatment. We found that FBXL7 was downregulated in OVSAHO (PTX-sensitive) but upregulated in KURAMOCHI (PTX-resistant) cells after PTX treatment at cytotoxic concentrations. Moreover, our data showed that the fold change of FBXL7 expression post-treatment with PTX was causally correlated with the 50% inhibitory concentrations (IC50) of PTX in a panel of ovarian cancer cell lines. In assessments of progression-free survival probability, high levels of FBXL7 transcript strongly predicted a poor prognosis and unfavorable response to PTX-based chemotherapy in patients with ovarian cancer. The knockdown of FBXL7 predominantly enhanced the cytotoxic effectiveness of PTX on the PTX-resistant KURAMOCHI cells. FBXL7 may be a useful biomarker for predicting complete pathologic response in ovarian cancer patients who decide to receive post-operative PTX therapy.