Targeting NG2 relieves the resistance of BRAF-mutant thyroid cancer cells to BRAF inhibitors.

BRAFV600E represents a constitutively active onco-kinase and stands as the most prevalent genetic alteration in thyroid cancer. However, the clinical efficacy of small-molecule inhibitors targeting BRAFV600E is often limited by acquired resistance. Here, we find that nerve/glial antigen 2 (NG2), also known as chondroitin sulfate proteoglycan 4 (CSPG4), is up-regulated in thyroid cancers, and its expression is increased with tumor progression in a BRAFV600E-driven thyroid cancer mouse model. Functional studies show that NG2 knockout almost does not affect tumor growth, but significantly improves the response of BRAF-mutant thyroid cancer cells to BRAF inhibitor PLX4720. Mechanistically, the blockade of ERK-dependent feedback by BRAF inhibitor can activate receptor tyrosine kinase (RTK) signaling, causing the resistance to this inhibitor. NG2 knockout attenuates the PLX4720-mediated feedback activation of several RTKs, improving the sensitivity of BRAF-mutant thyroid cancer cells to this inhibitor. Based on this finding, we propose and demonstrate an alternative strategy for targeting NG2 to effectively treat BRAF-mutant thyroid cancers by combining multiple kinase inhibitor (MKI) Sorafenib or Lenvatinib with PLX4720. Thus, this study uncovers a new mechanism in which NG2 contributes to the resistance of BRAF-mutant thyroid cancer cells to BRAF inhibitor, and provides a promising therapeutic option for BRAF-mutant thyroid cancers.

Differential expression and prognostic value of TLR4 in kidney renal clear cell carcinoma.

Human Toll-like receptor (TLR) family plays a crucial role in immunity and cancer progression. However, the specific role of human Toll-like receptor 4 (TLR4) in kidney renal clear cell carcinoma (KIRC) remains obscure. Thus, we used single-cell RNA sequencing (RNA-seq) and bulk RNA-seq data combined with in vitro studies to evaluate the expression and prognostic value of TLR4 in KIRC. In our study, we observed that TLR4 was over expressed in KIRC tissues compared to normal renal tissues. And the expression of TLR4 was higher in macrophages/monocytes than other cell types. Besides, there is a close association between TLR4 expression and immune cell infiltration (Neutrophils, Macrophages, T cells and B cells) in KIRC. Immunohistochemical staining also showed that TLR4 was overexpressed in inflammatory infiltration renal tissue compared with normal tissue. Meanwhile, high expression of TLR4 exhibited correlations with improved survival, lower tumor grade and stage. Interestingly, the protective significance of TLR4 only showed in female patients (HR = 0.37, P < 0.01), other than male patients (HR = 0.71, P = 0.08) with KIRC. Consistently, KIRC samples with lymph node metastasis showed lower expression of TLR4. Knockdown of TLR4 in 786-O cell line increased cell proliferation and clonogenic capacity. In summary, this study found TLR4 could inhibit the progression of kidney cancer and was associated with improved survival in KIRC. The overexpression of TLR4 in macrophages and the close association between TLR4 and immune cell infiltration also underline the critical role of TLR4 in building the immune microenvironment for kidney cancer. These results may offer insights into the mechanism and immune microenvironment of kidney cancer.

High expression of RTEL1 predicates worse progression in gliomas and promotes tumorigenesis through JNK/ELK1 cascade.

Gliomas are the most common primary intracranial tumor worldwide. The maintenance of telomeres serves as an important biomarker of some subtypes of glioma. In order to investigate the biological role of RTEL1 in glioma. Relative telomere length (RTL) and RTEL1 mRNA was explored and regression analysis was performed to further examine the relationship of the RTL and the expression of RTEL1 with clinicopathological characteristics of glioma patients. We observed that high expression of RTEL1 is positively correlated with telomere length in glioma tissue, and serve as a poor prognostic factor in TERT wild-type patients. Further in vitro studies demonstrate that RTEL1 promoted proliferation, formation, migration and invasion ability of glioma cells. In addition, in vivo studies also revealed the oncogene role of RTEL1 in glioma. Further study using RNA sequence and phospho-specific antibody microarray assays identified JNK/ELK1 signaling was up-regulated by RTEL1 in glioma cells through ROS. In conclusion, our results suggested that RTEL1 promotes glioma tumorigenesis through JNK/ELK1 cascade and indicate that RTEL1 may be a prognostic biomarker in gliomas.

MYO5A overexpression promotes invasion and correlates with low lymphocyte infiltration in head and neck squamous carcinoma.

Head and neck squamous carcinoma (HNSC) poses a significant public health challenge due to its substantial morbidity. Nevertheless, despite advances in current treatments, the prognosis for HNSC remains unsatisfactory. To address this, single-cell RNA sequencing (RNA-seq) and bulk RNA-seq data combined with in vitro studies were conducted to examine the role of MYO5A (Myosin VA) in HNSC. Our investigation revealed an overexpression of MYO5A in HNSC that promotes HNSC migration in vitro. Remarkably, knockdown of MYO5A suppressed vimentin expression. Furthermore, analyzing the TCGA database evidenced that MYO5A is a risk factor for human papillomavirus positive (HPV+) HNSC (HR = 0.81, P < 0.001). In high MYO5A expression HNSC, there was a low count of tumor infiltrating lymphocytes (TIL), including activated CD4+ T cells, CD8+ T cells, and B cells. Of note, CD4+ T cells and B cells were positively associated with improved HPV+ HNSC outcomes. Correlation analysis demonstrated a decreased level of immunostimulators in high MYO5A-expressing HNSC. Collectively, these findings suggest that MYO5A may promote HNSC migration through vimentin and involve itself in the process of immune infiltration in HNSC, advancing the understanding of the mechanisms and treatment of HNSC.

Screening protective miRNAs and constructing novel lncRNAs/miRNAs/mRNAs networks and prognostic models for triple-negative breast cancer.

Triple-negative breast cancer (TNBC) represents 10-20 % of all breast cancer (BC) cases and is characterized by poor prognosis. Given the urgent need to improve prognostication and develop specific therapies for TNBC, the identification of new molecular targets is of great importance. MicroRNA (miRNA) has been reported as a valuable and novel molecular target in the progression of TNBC. However, the expression and function of miRNAs in different tumors are heterogeneous. Herein, we first analyzed miRNA data from The Cancer Genome Atlas (TCGA) and surprisedly found that overexpressed miRNAs were associated with poor survival in all breast cancer patients, but the overexpressed miRNAs were associated with better survival in TNBC patients. Based on the heterogeneity of miRNA expression in TNBC, we conducted further analysis using univariate Cox proportional hazard regression models and identified 17 miRNAs with prognostic potential. Subsequently, a multivariate Cox model was employed to create a 3-miRNA prognostic model for predicting overall survival in TNBC patients. The diagnostic model exhibited an area under the curve (AUC) of 0.727, and multivariable Cox regression indicated that each covariate was associated with survival. These data indicate that this model is relatively accurate and robust for risk assessment, which have a certain value for clinical application. In order to explore the network behind the overexpressed miRNAs in TNBC, we established a novel network consisting of lncRNAs, miRNAs, and mRNAs through complete transcriptome data from matched samples in the TCGA database. In this network, IRS-1 appeared to be the top hub gene. Experimental results demonstrated that miR-15b-5p and miR-148a-3p effectively target IRS-1 in vitro, shedding light on the intricate regulatory mechanisms in TNBC mediated by the heterogeneous miRNAs. Besides, miR-148a-3p significantly inhibited cell migration and viability. Overall, this study may add valuable insights into the molecular landscape of TNBC based on miRNAs and have the potential to contribute to the development of targeted therapies and improved prognostic strategies of TNBC.

High PGAP3 expression is associated with lymph node metastasis and low CD8+T cell in patients with HER2+ breast cancer.

BACKGROUND: Breast cancer (BC) stands as the most prevalent malignancy among women and ranks as the second most frequently diagnosed cancer globally among newly identified cases. Post-GPI attachment to proteins factor 3（PGAP3）was reported to involve in lipid remodeling. However, its specific role in breast cancer remains inadequately elucidated. Consequently, the principal objective of this study was to investigate the clinical significance of PGAP3 in breast cancer. METHODS: We conducted an extensive analysis using both public databases and our own sample cohort to assess the role of PGAP3 in breast cancer. Immunohistochemistry was employed to assess PGAP3 expression, immune markers, and the co-expression of PGAP3 with key susceptibility genes. Data analysis was performed using the R programming language. RESULTS: Our findings revealed that PGAP3 is significantly overexpressed in breast cancer, particularly in human epidermal growth factor 2 positive (HER2 +) breast cancer cases (p < 0.001). Co-expression analyses demonstrated a significant correlation between PGAP3 and susceptibility genes associated with breast cancer, including BRCA1, BRCA2, PALB2, ATM, CHEK2, RAD51C, and RAD51D (p < 0.05). Logistic regression analysis identified PGAP3 as a significant predictor of estrogen receptor (ER), progesterone receptor (PR), HER2, and lymph node metastasis status (p < 0.01). Furthermore, higher PGAP3 expression was associated with decreased infiltration of CD8 + T cells in breast cancer samples. CONCLUSION: Our study sheds light on the clinical significance of PGAP3 in breast cancer. PGAP3 is not only overexpressed in breast cancer but also correlates with key susceptibility genes, lymph node metastasis, and CD8 + T cell infiltration. These findings provide valuable insights into the potential role of PGAP3 as a biomarker in breast cancer and may contribute to our understanding of the disease's pathogenesis.

Comparison of postoperative recovery of primary pterygium excision combined with either limbal stem cell transplantation or amniotic membrane transplantation: a randomized controlled trial-based meta-analysis.

OBJECTIVE: To compare the postoperative recovery of primary pterygium excision combined with either limbal stem cell transplantation (LSCT) or amniotic membrane transplantation (AMT). METHODS: All relevant studies on the primary pterygium excision combined with either LSCT or AMT conducted before August 2022 were extracted from PubMed, EMBASE, Web of Science, and Cochrane Library databases. The main outcomes compared were tear film stability at 1, 3, and 6 months after surgery, postoperative corneal epithelial healing time, recurrence rate, and complications. RESULTS: Sixteen randomized controlled trials (RCTs) with 1390 eye cases were included in this meta-analysis. We found that patients of the AMT group improved significantly in the results of the tear break-up time (BUT) and Schirmer I test at 1 month after surgery (BUT: MD=-0.37, 95% CI: -0.62, -0.12, P<0.05; Schirmer I test: MD=-0.32, 95% CI: -0.57, -0.07, P<0.05) compared with those of the LSCT group, suggesting that the early stage of tear film stability after primary pterygium excision combined with AMT was superior to the LSCT combination. However, according to the Schirmer I test result, the patients in the LSCT group showed increased tear production compared to the AMT group at 3 and 6 months after surgery (3 months: MD=0.36, 95% CI: 0.08, 0.64, P<0.05; 6 months: MD=0.33, 95% CI: 0.07, 0.60, P<0.05), suggesting that the LSCT combination was superior to the AMT combination in long-term postoperative tear film stability. As for postoperative corneal epithelial healing time, the LSCT group exhibited shorter time than the AMT group (MD=-1.17, 95% CI: -2.15, -0.19, P<0.05). Furthermore, the recurrence rate was lower in the LSCT group than in the AMT group (RR=0.42, 95% CI: 0.30, 0.59, P<0.05). Lastly, there was no statistical difference in BUT and complication rate at 3 and 6 months after surgery between the LSCT and AMT groups. CONCLUSIONS: Our analysis suggests that primary pterygium excision combined with LSCT may be a better choice compared to the combination with AMT in postoperative recovery.

Sorafenib decreases glycemia by impairing hepatic glucose metabolism.

PURPOSE: Sorafenib has been reported to reduce blood glucose levels in diabetic and non-diabetic patients in previous retrospective studies. However, the mechanism of which the hypoglycemic effects of sorafenib is not clearly explored. In this study, we investigated the effect of sorafenib on blood glucose levels in diabetic and normal mice and explored the possible mechanism. METHODS: We established a mouse model of type 2 diabetes by a high-fat diet combined with a low-dose of streptozotocin (STZ), to identify the hypoglycemic effect of sorafenib in different mice. Glucose tolerance, insulin tolerance and pyruvate tolerance tests were done after daily gavage with sorafenib to diabetic and control mice. To explore the molecular mechanism by which sorafenib regulates blood glucose levels, hepatic glucose metabolism signaling was studied by a series of in vivo and in vitro experiments. RESULTS: Sorafenib reduced blood glucose levels in both control and diabetic mice, particularly in the latter. The diabetic mice exhibited improved glucose and insulin tolerance after sorafenib treatment. Further studies showed that the expressions of gluconeogenesis-related enzymes, such as PCK1, G6PC and PCB, were significantly decreased upon sorafenib treatment. Mechanistically, sorafenib downregulates the expression of c-MYC downstream targets PCK1, G6PC and PCB through blocking the ERK/c-MYC signaling pathway, thereby playing its hypoglycemic effect by impairing hepatic glucose metabolism. CONCLUSION: Sorafenib reduces blood glucose levels through downregulating gluconeogenic genes, especially in diabetic mice, suggesting the patients with T2DM when treated with sorafenib need more emphasis in monitoring blood glucose to avoid unnecessary hypoglycemia.

FBXO39 predicts poor prognosis and correlates with tumor progression in cervical squamous cell carcinoma.

BACKGROUND: Cancer/testis antigen (CTA) is a class of antigen molecules mainly expressed in the germinal epithelium of testis and some tumor tissues. FBXO39, also known as F-box protein 39, is a crucial CTA molecule. F-box protein 39 (FBXO39) is overexpressed in cervical squamous cell carcinomas (CESCs), however its function in cancer development and clinical significance are still unknown. METHODS: We used paraffin-embedded tumor tissues from 124 patients and fresh-harvested and paired adjacent normal esophageal tissues from 15 CESC patients who underwent primary surgical resection in Xijing Hospital between 2015 and 2020. The expression level of FBXO39 was evaluated through immunohistochemistry, Western Blot and q-PCR. Prognostic and survival analyses were conducted using univariate/multivariate analysis and log-rank analysis with SPSS 23.0. CCK-8, wound-healing and Transwell assays were applied to demonstrate that FBXO39 promoted the proliferation, migration and invasion. Finally, we constructed a xenografts model of the C-33A cell lines to observe the effect of FBXO39 on tumorigenesis in vivo. RESULTS: Immunohistochemical results showed that FBXO39 was highly expressed in cancer tissues than in corresponding non-cancer tissues. Similarly, we proved this result at protein and mRNA level by Western-Blotting and q-PCR. Prognostic and OS analyses showed that the FBXO39 expression level was an individual prognostic factor in CESC patients. CCK-8, wound-healing and Transwell assays proved that the overexpression of FBXO39 in Si-Ha cells promoted the proliferation, migration and invasion of the cells. Knocking down FBXO39 in C-33A cells inhibited the proliferation, migration and invasion of cells. The experimental results of xenografts model in nude mice showed that the knockdown of FBXO39 in C-33A cells slowed down the growth of tumor. CONCLUSION: FBXO39 is a poor prognostic factor of cervical squamous cell carcinoma, which may provide a novel therapeutic target for CESC.

New screening approach to detecting congenital syphilis in China: a retrospective cohort study.

BACKGROUND: Diagnosis of congenital syphilis (CS) is not straightforward and can be challenging. This study aimed to evaluate the validity of an algorithm using timing of maternal antisyphilis treatment and titres of non-treponemal antibody as predictors of CS. METHODS: Confirmed CS cases and those where CS was excluded were obtained from the Guangzhou Prevention of Mother-to-Child Transmission of syphilis programme between 2011 and 2019. We calculated sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) using receiver operating characteristics (ROC) in two situations: (1) receiving antisyphilis treatment or no-treatment during pregnancy and (2) initiating treatment before 28 gestational weeks (GWs), initiating after 28 GWs or receiving no treatment for syphilis seropositive women. RESULTS: Among 1558 syphilis-exposed children, 39 had confirmed CS. Area under the curve, sensitivity and specificity of maternal non-treponemal titres before treatment and treatment during pregnancy were 0.80, 76.9%, 78.7% and 0.79, 69.2%, 88.7%, respectively, for children with CS. For the algorithm, ROC results showed that PPV and NPV for predicting CS were 37.3% and 96.4% (non-treponemal titres cut-off value 1:8 and no antisyphilis treatment), 9.4% and 100% (non-treponemal titres cut-off value 1:16 and treatment after 28 GWs), 4.2% and 99.5% (non-treponemal titres cut-off value 1:32 and treatment before 28 GWs), respectively. CONCLUSIONS: An algorithm using maternal non-treponemal titres and timing of treatment during pregnancy could be an effective strategy to diagnose or rule out CS, especially when the rate of loss to follow-up is high or there are no straightforward diagnostic tools.

Vitamin C kills thyroid cancer cells through ROS-dependent inhibition of MAPK/ERK and PI3K/AKT pathways via distinct mechanisms.

Background: Vitamin C has been demonstrated to kill BRAF mutant colorectal cancer cells selectively. BRAF mutation is the most common genetic alteration in thyroid tumor development and progression; however, the antitumor efficacy of vitamin C in thyroid cancer remains to be explored. Methods: The effect of vitamin C on thyroid cancer cell proliferation and apoptosis was assessed by the MTT assay and flow cytometry. Xenograft and transgenic mouse models were used to determine its in vivo antitumor activity of vitamin C. Molecular and biochemical methods were used to elucidate the underlying mechanisms of anticancer activity of vitamin C in thyroid cancer. Results: Pharmaceutical concentration of vitamin C significantly inhibited thyroid cancer cell proliferation and induced cell apoptosis regardless of BRAF mutation status. We demonstrated that the elevated level of Vitamin C in the plasma following a high dose of intraperitoneal injection dramatically inhibited the growth of xenograft tumors. Similar results were obtained in the transgenic mouse model. Mechanistically, vitamin C eradicated BRAF wild-type thyroid cancer cells through ROS-mediated decrease in the activity of EGF/EGFR-MAPK/ERK signaling and an increase in AKT ubiquitination and degradation. On the other hand, vitamin C exerted its antitumor activity in BRAF mutant thyroid cancer cells by inhibiting the activity of ATP-dependent MAPK/ERK signaling and inducing proteasome degradation of AKT via the ROS-dependent pathway. Conclusions: Our data demonstrate that vitamin C kills thyroid cancer cells by inhibiting MAPK/ERK and PI3K/AKT pathways via a ROS-dependent mechanism and suggest that pharmaceutical concentration of vitamin C has potential clinical use in thyroid cancer therapy.

Self-Assembly of Therapeutic Peptide into Stimuli-Responsive Clustered Nanohybrids for Cancer-Targeted Therapy.

Clinical translation of therapeutic peptides, particularly those targeting intracellular protein-protein interactions (PPIs), has been hampered by their inefficacious cellular internalization in diseased tissue. Therapeutic peptides engineered into nanostructures with stable spatial architectures and smart disease targeting ability may provide a viable strategy to overcome the pharmaceutical obstacles of peptides. This study describes a strategy to assemble therapeutic peptides into a stable peptide-Au nanohybrid, followed by further self-assembling into higher-order nanoclusters with responsiveness to tumor microenvironment. As a proof of concept, an anticancer peptide termed ß-catenin/Bcl9 inhibitors is copolymerized with gold ion and assembled into a cluster of nanohybrids (pCluster). Through a battery of in vitro and in vivo tests, it is demonstrated that pClusters potently inhibit tumor growth and metastasis in several animal models through the impairment of the Wnt/ß-catenin pathway, while maintaining a highly favorable biosafety profile. In addition, it is also found that pClusters synergize with the PD1/PD-L1 checkpoint blockade immunotherapy. This new strategy of peptide delivery will likely have a broad impact on the development of peptide-derived therapeutic nanomedicine and reinvigorate efforts to discover peptide drugs that target intracellular PPIs in a great variety of human diseases, including cancer.

Turning a Luffa Protein into a Self-Assembled Biodegradable Nanoplatform for Multitargeted Cancer Therapy.

The peptide-derived self-assembly platform has attracted increasing attention for its great potential to develop into multitargeting nanomedicines as well as its inherent biocompatibility and biodegradability. However, their clinical application potentials are often compromised by low stability, weak membrane penetrating ability, and limited functions. Herein, inspired by a natural protein from the seeds of Luffa cylindrica, we engineered via epitope grafting and structure design a hybrid peptide-based nanoplatform, termed Lupbin, which is capable of self-assembling into a stable superstructure and concurrently targeting multiple protein-protein interactions (PPIs) located in cytoplasm and nuclei. We showed that Lupbin can efficiently penetrate cell membrane, escape from early endosome-dependent degradation, and subsequently disassemble into free monomers with wide distribution in cytosol and nucleus. Importantly, Lupbin abrogated tumor growth and metastasis through concurrent blockade of the Wnt/ß-catenin signaling and reactivation of the p53 signaling, with a highly favorable in vivo biosafety profile. Our strategy expands the application of self-assembled nanomedicines into targeting intercellular PPIs, provides a potential nanoplatform with high stability for multitargeted cancer therapy, and likely reinvigorates the development of peptide-based therapeutics for the treatment of different human diseases including cancer.

Gender-related differences in the association between concomitant amplification of AIB1 and HER2 and clinical outcomes in glioma patients.

BACKGROUND: Previous studies demonstrated that AIB1 or HER2 copy number gain (CNG), respectively, were independent predictors for poor prognosis of glioma patients, especially in females. We hypothesize that there are some connections between the two genes and sex-specific characteristics, thus this study aimed to analyze gender-related differences in the prognosis of glioma patients. METHODS: Using Real-Time Quantitative Reverse Transcription PCR (RT-qPCR) method, we examined AIB1 and HER2 CNG in gliomas samples (n = 114), and inspected the correlation of various genotypes with patients outcomes. RESULTS: Concomitant AIB1 and HER2 amplification were closely related to shorter survival time and radiotherapy resistance in female gliomas patients (P < 0.01), which also served as an independent risk factor. No significant prognostic value was found with AIB1 and HER2 CNG in male patients. However, linear regression analysis showed a positive relationship between the copy number of AIB1 and HER2 (P < 0.01) in male patients, rather than female patients. CONCLUSION: In this study, we reveal a gender difference in the prognostic value of concomitant AIB1 and HER2 CNG in glioma patients which were barely noticed before. These observations indicated that genetic alterations synergistic with essential respects of sex determination influence glioma biology and patients outcomes.

Long non-coding RNAs in thyroid cancer: Biological functions and clinical significance.

Thyroid cancer is the most common endocrine malignant tumor with rapidly increasing incidence in recent decades. Although the majority of thyroid cancers are relatively indolent, some cases still have a risk of developing into more aggressive and lethal forms of thyroid cancers. Similar to other malignancies, thyroid tumorigenesis is a multistep process involving the accumulation of a large number of genetic and epigenetic alterations. Thus, determination of the mechanisms of tumorigenesis is an urgent need for thyroid cancer treatment. Long noncoding RNAs (LncRNAs) have recently been demonstrated to participate in cancer progression. However, their role and molecular mechanism in thyroid cancer remain largely unclear. In this review, we focus on the dysregulation of lncRNAs in thyroid cancer, summarize the latest findings regarding the functions and mechanism of lncRNAs in thyroid cancer, and discuss their potential clinical significance in diagnosis and prognosis of thyroid cancer.

Peptide-Induced Self-Assembly of Therapeutics into a Well-Defined Nanoshell with Tumor-Triggered Shape and Charge Switch.

Peptide-tuned self-assembly of macromolecular agents (>500 Da) such as therapeutic peptides offers a strategy to improve the properties and biofunctions of degradable nanomaterials, but the tough requirement of macromolecular therapeutics delivery and a lack of understanding of peptide-based self-assembly design present high barriers for their applications. Herein, we developed a new strategy for nanoengineering macromolecular drugs by an elaborate peptide, termed PSP (VVVVVHHRGDC), capable of directly conjugating with cargo to be a PSP-cargo monomer as building block tending to self-assemble into a well-defined nanoshell with tumor-triggered shape and charge switch. As a proof of concept, conjugation PSP to a D-peptide activator of tumor suppressor p53 termed DPMI (1492.5 Da) generated hollow spheres ~80 nm in diameter named PSP-DPMI that disintegrated only in the acidic microenvironment of tumor tissues, followed by integrin-mediated cellular uptake of PSP-DPMI monomers. Importantly, PSP-based self-assembly successfully endowed the DPMI with long circulation time and high cancer-cell-specific intracellular accumulation. PSP-DPMI nanoshells potently inhibited tumor growth in vitro and in vivo by the p53 restoration, while maintaining a highly favorable in vivo safety profile. Out of conventional encapsulation and conjugation, our study showcases a clinically viable novel method to nanoengineer macromolecular agents such as peptide for anticancer therapy and provides a hazard-free alternative strategy for the theranostics delivery.

Identification of MAP kinase pathways as therapeutic targets in gallbladder carcinoma using targeted parallel sequencing.

The aim of this study was to profile somatic mutation spectrum in gallbladder cancers (GBCs), and determine the role of MAP kinase pathway in GBC by a series of in vitro and in vivo studies. We performed targeted massively parallel sequencing of DNA isolated from GBCs and matched blood from 14 GBC patients to search for mutations in 504 genes commonly altered in human cancers. We identified recurrent mutations enriched in several major signaling pathways including MAP kinase, Wnt/ß-catenin and NF-κB pathways. Immunohistochemistry analysis further validated overactivation of MAP kinase and Wnt pathways in a panel of GBC samples. By treating GBC cells with MEK inhibitor trametinib, we found that trametinib not only dramatically inhibited the activity of MAPK/ERK pathway, but also blocked the Wnt/ß-catenin signaling through decreasing ß-catenin expression or suppressing nucleus translocation of ß-catenin. Moreover, trametinib inhibited the proliferation of GBC cell in a dose- and time-dependent manner, induced GBC cell apoptosis, and inhibited GBC cell migration and invasion. Growth of xenograft tumors derived from GBC cell line NOZ in nude mice was also significantly inhibited by trametinib. Our data highlight the critical role of MAP kinase pathways in GBC pathogenesis, and may represent therapeutic targets for this cancer.

Proteasome inhibitor MG132 induces thyroid cancer cell apoptosis by modulating the activity of transcription factor FOXO3a.

Proteasome inhibitors are promising antitumor drugs with preferable cytotoxicity in malignant cells and have exhibited clinical efficiency in several hematologic malignancies. P53-dependent apoptosis has been reported to be a major mechanism underlying. However, apoptosis can also be found in cancer cells with mutant-type p53, suggesting the involvement of p53-independent mechanism. Tumor suppressor forkhead Box O3 is another substrate of proteasomal degradation, which also functions partially through inducing apoptosis. The aim of this study was to explore the effect of proteasome inhibition on the expression and activity of forkhead Box O3 in thyroid cancer cells. Using flow cytometry, western blot, immunofluorescence staining and quantitative RT-PCR assays, we assessed proteasome inhibitor MG132-induced apoptosis in thyroid cancer cells and its effect on the expression and activity of forkhead Box O3. The resulted showed that MG132 induced significant apoptosis, and caused the accumulation of p53 protein in both p53 wild-type and mutant-type thyroid cancer cell lines, whereas the proapoptotic targets of p53 were transcriptionally upregulated only in the p53 wild-type cells. Strikingly, upon MG132 administration, the accumulation and nuclear translocation of transcription factor forkhead Box O3 as well as transcriptional upregulation of its proapoptotic target genes were found in thyroid cancer cells regardless of p53 status. Cell apoptosis was enhanced by ectopic overexpression while attenuated by silencing of forkhead Box O3. Altogether, we demonstrated that proteasome inhibitor MG132 induces thyroid cancer cell apoptosis at least partially through modulating forkhead Box O3 activity.

Positive Feedback Loops Between NrCAM and Major Signaling Pathways Contribute to Thyroid Tumorigenesis.

Context: Although neuronal cell adhesion molecule (NrCAM) has been reported to be overexpressed in papillary thyroid cancer (PTCs), its role in this disease remains largely unclear. Objectives: The aim of this study was to explore the biological functions of NrCAM and its potential as a diagnostic marker and therapeutic target in thyroid cancer. Experimental Design: Quantitative real-time polymerase chain reaction (qRT-PCR) was performed to evaluate messenger RNA expression of investigated genes. The functions of knockdown and ectopic expression of NrCAM in thyroid cancer cells were determine by a series of in vitro and in vivo experiments. Results: We found that NrCAM was highly expressed in PTCs and demonstrated that NrCAM might be a potential marker for preoperative diagnosis of PTC. Moreover, NrCAM depletion dramatically inhibited thyroid cancer cell growth, invasiveness and tumorigenic potential in nude mice. On the other hand, ectopic expression of NrCAM significantly enhanced its tumor-promoting effects. Mechanically, NrCAM exerted its oncogenic function by activating MAPK/Erk and PI3K/Akt pathways via its ectodomain shedding and binding to EGFR and α4ß1 integrins. In turn, these 2 pathways were also responsible for NrCAM overexpression through GSK3ß/ß-catenin signaling axis in thyroid cancer cells. Similar results were also found in transgenic mice with thyroid-specific knock-in of oncogenic BrafV600E (TPO-Cre/LSL-BrafV600E). Conclusions: Our data first reveal positive feedback loops between NrCAM and major signaling pathways contributing to thyroid tumorigenesis by modulating tumor microenvironment, and suggest that NrCAM may represent a potential diagnostic marker and therapeutic target for thyroid cancer.

Increased expression of EHF via gene amplification contributes to the activation of HER family signaling and associates with poor survival in gastric cancer.

The biological function of E26 transformation-specific (ETS) transcription factor EHF/ESE-3 in human cancers remains largely unknown, particularly gastric cancer. The aim of this study was to explore the role of EHF in tumorigenesis and its potential as a therapeutic target in gastric cancer. By using quantitative RT-PCR (qRT-PCR), immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH) assays, we investigated the expression and copy number of EHF in a cohort of gastric cancers and control subjects. Specific EHF siRNAs was used to determine the biologic impacts and mechanisms of altered EHF expression in vitro and in vivo. Dual-luciferase reporter, chromatin immunoprecipitation (ChIP) and electrophoretic mobility shift assay (EMSA) assays were performed to identify its downstream targets. Our results demonstrated that EHF was significantly upregulated and frequently amplified in gastric cancer tissues as compared with control subjects. Moreover, EHF amplification was positively correlated with its overexpression and significantly associated with poor clinical outcomes of gastric cancer patients. We also found that EHF knockdown notably inhibited gastric cancer cell proliferation, colony formation, migration, invasion and tumorigenic potential in nude mice and induced cell cycle arrest and apoptosis. Importantly, we identified EHF as a new HER2 transcription factor and the modulator of HER3 and HER4 in gastric cancer. Collectively, our findings suggest that EHF is a novel functional oncogene in gastric cancer by regulating the human epidermal growth factor receptor (HER) family of receptor tyrosine kinases and may represent a potential prognostic marker and therapeutic target for this cancer.