Synchronous multiple primary malignancies of clear cell renal cell carcinoma with sarcomatoid, thyroid carcinoma: a case report.

Multiple primary malignant neoplasms (MPMNs) are defined as the presence of two or more malignancies with different histologies in the same patient. MPMNs are rare, accounting for fewer than 4% of all tumor cases. Depending on the time interval between the diagnosis of the different malignancies, they are classified as either simultaneous or metachronous MPMNs, with simultaneous being rarer in MPMNs. Here, we present a 63-year-old female patient presenting with multiple primary renal and thyroid carcinomas and discuss the risk factors, treatment options, and prognosis of rare dual carcinomas. We focus on managing multidisciplinary teams and selecting individualized treatment options to deliver valuable treatment strategies to patients.

Case Report: Clinical application of immunotherapy-based combination regimen in primary osteosarcoma of the uterus.

Primary osteosarcoma of the uterus is an extremely rare pure heterologous sarcoma of the uterus. The relevant available information is limited to case reports. To date, only 31 cases of this type of cancer have been reported. Here, we report the first clinical experience with the administration of an immunotherapy-based combination regimen for multiple metastatic primary osteosarcomas of the uterus. The patient had undergone multiple treatments prior to this regimen, but her condition continued to progress. However, after 3 cycles of immunotherapy combined with targeted therapy and chemotherapy, a review showed that the disease was stable and even in partial remission. The patient has a good quality of life, and long-term survival is expected.

Imaging evaluation of para-aortic lymph nodes in cervical cancer.

BACKGROUND: In recent years, much literature has reported the diagnostic value of computed tomography (CT), magnetic resonance imaging (MRI), and positron emission tomography (PET)-CT in para-aortic lymph node metastasis of cervical cancer. PURPOSE: To compare and analyze the para-aortic lymph node presentations found in cervical cancer on different images in order to determine the best precise imaging method for identifying metastatic lymph nodes. MATERIAL AND METHODS: PubMed, Web of Science, MEDLINE, and other databases were searched for the non-invasive detection of metastatic lymph nodes for a comprehensive comparison. RESULTS: Positive lymph nodes on CT are significantly related to the following factors: short axis ≥10 mm; and round or central necrosis. Positive lymph nodes on MRI are significantly related to the following factors: short axis ≥8 mm; inhomogeneous signal intensity; morphology: round, irregular edge, extracapsular invasion, central necrosis, loss of lymph node structure, burrs, or lobes; and ADC value decreases, combined with local actuality. On PET-CT examination, when the short axis of the lymph node is >5 mm, the SUV is >2.5, or the FDG uptake is greater than that of the surrounding tissue, it is a metastatic lymph node. CONCLUSION: In conclusion, different imaging techniques show metastatic lymph nodes in different ways. Combining the patient's medical history with the symptoms of the aforementioned lymph nodes, together with one or more imaging techniques, is important to diagnose para-aortic lymph nodes in cervical cancer.

Comprehensive analysis of oxidative stress-related lncRNA signatures in glioma reveals the discrepancy of prognostic and immune infiltration.

Oxidative stress refers to the process of reactive oxide species (ROS) increase in human body due to various factors, which leads to oxidative damage in human tissues. Current studies have confirmed that sustained oxidative stress is one of the distinctive features throughout the development of tumors. Numerous reports have shown that lncRNAs can regulate the process of oxidative stress through multiple pathways. However, the relationship between glioma-associated oxidative stress and lncRNAs is not clearly investigated. RNA sequencing data of GBM (glioblastoma) and LGG (low grade glioma) and corresponding clinical data were retrieved from the TCGA database. Oxidative stress related lncRNAs (ORLs) were identified by Pearson correlation analysis. Prognostic models for 6-ORLs were structured in the training cohort by univariate Cox regression analysis, multivariate Cox regression analysis and LASSO regression analysis. We constructed the nomogram and verified its predictive efficacy by Calibration curves and DCA decision curves. The biological functions and pathways of 6-ORLs-related mRNAs were inferred by Gene Set Enrichment Analysis. Immune cell abundance and immune function associated with risk score (RS) were estimated by ssGSEA, CIBERSORT and MCPcounter synthetically. External validation of the signature was completed using the CGGA-325 and CGGA-693 datasets. 6-ORLs signature-AC083864.2, AC107294.1, AL035446.1, CRNDE, LINC02600, and SNAI3-AS1-were identified through our analysis as being predictive of glioma prognosis. Kaplan-Meier and ROC curves indicated that the signature has a dependable predictive efficacy in the TCGA training cohort, validation cohort and CGGA-325/CGGA-693 test cohort. The 6-ORLs signature were verified to be independent prognostic predictors by multivariate cox regression and stratified survival analysis. Nomogram built with risk scores had strong predictive efficacy for patients' overall survival (OS). The outcomes of the functional enrichment analysis revealing potential molecular regulatory mechanisms for the 6-ORLs. Patients in the high-risk subgroup presented a significant immune microenvironment of macrophage M0 and cancer-associated fibroblast infiltration which was associated with a poorer prognosis. Finally, the expression levels of 6-ORLs in U87/U251/T98/U138 and HA1800 cell lines were verified by RT-qPCR. The nomogram in this study has been made available as a web version for clinicians. This 6-ORLs risk signature has the capabilities to predict the prognosis of glioma patients, assist in evaluating immune infiltration, and assess the efficacy of various anti-tumor systemic therapy regimens.

The Construction of a Prognostic Model Based on a Peptidyl Prolyl Cis-Trans Isomerase Gene Signature in Hepatocellular Carcinoma.

Objective: The aim of the present study was to construct a prognostic model based on the peptidyl prolyl cis-trans isomerase gene signature and explore the prognostic value of this model in patients with hepatocellular carcinoma. Methods: The transcriptome and clinical data of hepatocellular carcinoma patients were downloaded from The Cancer Genome Atlas and the International Cancer Genome Consortium database as the training set and validation set, respectively. Peptidyl prolyl cis-trans isomerase gene sets were obtained from the Molecular Signatures Database. The differential expression of peptidyl prolyl cis-trans isomerase genes was analyzed by R software. A prognostic model based on the peptidyl prolyl cis-trans isomerase signature was established by Cox, Lasso, and stepwise regression methods. Kaplan-Meier survival analysis was used to evaluate the prognostic value of the model and validate it with an independent external data. Finally, nomogram and calibration curves were developed in combination with clinical staging and risk score. Results: Differential gene expression analysis of hepatocellular carcinoma and adjacent tissues showed that there were 16 upregulated genes. A prognostic model of hepatocellular carcinoma was constructed based on three gene signatures by Cox, Lasso, and stepwise regression analysis. The Kaplan-Meier curve showed that hepatocellular carcinoma patients in high-risk score group had a worse prognosis (p < 0.05). The receiver operating characteristic curve revealed that the area under curve values of predicting the survival rate at 1, 2, 3, 4, and 5 years were 0.725, 0.680, 0.644, 0.630, and 0.639, respectively. In addition, the evaluation results of the model by the validation set were basically consistent with those of the training set. A nomogram incorporating clinical stage and risk score was established, and the calibration curve matched well with the diagonal. Conclusion: A prognostic model based on 3 peptidyl prolyl cis-trans isomerase gene signatures is expected to provide reference for prognostic risk stratification in patients with hepatocellular carcinoma.

Application of an Autophagy-Related Gene Prognostic Risk Model Based on TCGA Database in Cervical Cancer.

Background: Autophagy plays an important role in the development of cancer. However, the prognostic value of autophagy-related genes (ARGs) in cervical cancer (CC) is unclear. The purpose of this study is to construct a survival model for predicting the prognosis of CC patients based on ARG signature. Methods: ARGs were obtained from the Human Autophagy Database and Molecular Signatures Database. The expression profiles of ARGs and clinical data were downloaded from the TCGA database. Differential expression analysis of CC tissues and normal tissues was performed using R software to screen out ARGs with an aberrant expression. Univariate Cox, Lasso, and multivariate Cox regression analyses were used to construct a prognostic model which was validated by using the test set and the entire set. We also performed an independent prognostic analysis of risk score and some clinicopathological factors of CC. Finally, a clinical practical nomogram was established to predict individual survival probability. Results: Compared with normal tissues, there were 63 ARGs with an aberrant expression in CC tissues. A risk model based on 3 ARGs was finally obtained by Lasso and Cox regression analysis. Patients with high risk had significantly shorter overall survival (OS) than low-risk patients in both train set and validation set. The ROC curve validated its good performance in survival prediction, suggesting that this model has a certain extent sensitivity and specificity. Multivariate Cox analysis showed that the risk score was an independent prognostic factor. Finally, we mapped a nomogram to predict 1-, 3-, and 5-year survival for CC patients. The calibration curves indicated that the model was reliable. Conclusion: A risk prediction model based on CHMP4C, FOXO1, and RRAGB was successfully constructed, which could effectively predict the prognosis of CC patients. This model can provide a reference for CC patients to make precise treatment strategy.

Inhibition of Euchromatic Histone Lysine Methyltransferase 2 (EHMT2) Suppresses the Proliferation and Invasion of Cervical Cancer Cells.

EHMT2 (euchromatic histone lysine methyltransferase 2), a histone methyltransferase, has been shown to be involved in multiple human cancers. In this study, we determined mRNA and protein expression of EHMT2 in cervical cancer cells and normal cervical epithelial cells. EHMT2 was inhibited with short hairpin RNA (shEHMT2) in cervical cancer cells. Cell viability, colony proliferation, apoptosis, adhesion, and invasion assays and Western blot were performed to assess the function of EHMT2. As a result, EHMT2 was upregulated in human cervical cancer cells compared to normal cervical epithelial cells. Suppression of EHMT2 expression impairs cell proliferation and induces apoptosis. Furthermore, EHMT2 silencing inhibited cell adhesion and invasion. Finally, knockdown of EHMT2 resulted in a reduction of the expression of the tumorigenic proteins Bcl-2, Mcl-1, and Survivin and in an increase in the expression of the anti-malignant protein E-cadherin. In conclusion, our data suggest that EHMT2 plays a key role in cell proliferation and metastatic capacity in cervical cancer cells and could serve as a potential therapeutic target.

MicroRNA-494-3p Promotes Cell Growth, Migration, and Invasion of Nasopharyngeal Carcinoma by Targeting Sox7.

BACKGROUND: There is mounting evidence that microRNAs play an important role in nasopharyngeal carcinoma, which is widely prevalent in South China and is the most prevalent metastatic cancer among head and neck cancers. Recently, it has been shown that miR-494 is involved in the progression and prognosis of nasopharyngeal carcinoma. However, little is known about the function and mechanism of miR-494-3p in nasopharyngeal carcinoma. In the present study, we aimed to investigate the effects of miR-494-3p on the migration and invasion of nasopharyngeal carcinoma and to further explore the underlying mechanisms of these processes. METHODS: The expression levels of miR-494-3p and Sox7 in nasopharyngeal carcinoma specimens and nasopharyngeal carcinoma cell lines were measured using quantitative reverse transcription polymerase chain reaction. Luciferase reporter assay, quantitative reverse transcription polymerase chain reaction, and Western blotting were used to confirm whether Sox7 was a direct target of miR-494-3p. Additionally, the roles of miR-494-3p and Sox7 on cell proliferation, migration, and invasion of nasopharyngeal carcinoma were analyzed by Cell Counting Kit-8 (CCK-8) assay, wound healing assay, and Boyden chamber assay, respectively. RESULTS: Our study demonstrated that miR-494-3p was commonly upregulated in nasopharyngeal carcinoma specimens and nasopharyngeal carcinoma cell lines compared with nontumor nasopharyngeal epithelial tissue or nasopharyngeal cells (NP69). Moreover, miR-494-3p negatively regulated Sox7 at the posttranscriptional level by binding to a specific site in the Sox7 3'-untranslated region. In addition, synthetic miR-494-3p mimics significantly promoted proliferation, migration, and invasion of S18 and S26 nasopharyngeal carcinoma cells, while a synthetic miR-494-3p inhibitor resulted in suppressed nasopharyngeal carcinoma cell migration and invasion. CONCLUSION: miR-494-3p promotes nasopharyngeal carcinoma cell growth, migration, and invasion by directly targeting Sox7. Our results suggest that miR-494-3p might be a potential therapeutic target for nasopharyngeal carcinoma.

Niclosamide sensitizes nasopharyngeal carcinoma to radiation by downregulating Ku70/80 expression.

The aim of the present study was to investigate whether niclosamide could sensitize the nasopharyngeal carcinoma cells to radiation and further explore the underlying mechanisms. CCK-8 assay was used to determine the effect of niclosamide on the proliferation of NPC cells. Colony formation assay was used to evaluate the radiosensitizing effect of niclosamide on NPC cells. Flow cytometry analysis was used to determine the apoptosis of NPC cells induced by niclosamide. Immunofluorescent staining was used to detect the formation of γ-H2AX foci and the localization of Ku70/80 proteins in NPC cells. Real-time PCR quantification analysis was used to examine the level of Ku70/80 mRNA. DNA damage repair-related proteins were detected by western blot analysis. Our results showed that niclosamide markedly suppressed the proliferation of NPC cells. Niclosamide pretreatment followed by irradiation reduced the colony forming ability of NPC cells. Niclosamide in combination with irradiation significantly increased the apoptotic rate of NPC cells. Niclosamide significantly reduced the transcriptional level of K70/80 but not the translocation of Ku70/80 protein induced by irradiation. In conclusion, our study demonstrated that niclosamide could inhibit the growth of NPC cells and sensitize the NPC cells to radiation via suppressing the transcription of Ku70/80.

Niclosamide enhances the cytotoxic effect of cisplatin in cisplatin-resistant human lung cancer cells via suppression of lung resistance-related protein and c-myc.

Lung cancer is a leading cause of cancer-associated mortality worldwide. The cisplatin (DDP)­based chemotherapy remains the foundation of treatment for the majority of patients affected by advanced non­small cell lung cancer (NSCLC). However, DDP­resistance limits the clinical utility of this drug in patients with advanced NSCLC. The aim of the present study was to investigate the inhibitory effect of niclosamide on human lung cancer cell growth and to investigate the possible underlying mechanism. The effects of niclosamide on the proliferation of human lung adenocarcinoma (A549) and DDP­resistant (CR) human lung adenocarcinoma (A549/DDP) cells were examined by Cell Counting kit­8 assay. The impact of niclosamide on the apoptosis of A549/DDP cells was detected by Annexin V­fluorescein isothiocyanate/propidium iodide assay. The expression levels of cisplatin­resistant­associated molecules (lung resistance­related protein and c­myc) following niclosamide treatment in A549/DDP cells were evaluated by western blot analysis. The results indicated that niclosamide in combination with DDP demonstrated a synergistic effect in A549/DDP cells and directly induced apoptosis, which may be associated with caspase­3 activation. Furthermore, niclosamide decreased the expression level of c­myc protein, which may influence DDP sensitivity of A549/DDP cells. Thus, the present study indicates that niclosamide combined with DDP exerts a synergistic effect in cisplatin­resistant lung cancer cells and may present as a promising drug candidate in lung cancer therapy.

Matrine suppresses the migration and invasion of NSCLC cells by inhibiting PAX2-induced epithelial-mesenchymal transition.

Non-small cell lung cancer (NSCLC) is the major cause of deaths among all the cancer types worldwide. Most of the NSCLC is diagnosed at an advanced stage and the 5-year overall survival rate is low. The reason for the low survival rate of patients with NSCLC is mainly due to distant metastasis. Matrine, a traditional Chinese medicine, has been shown a significant anti-proliferation and anti-invasive effect in tumors. However, little is known on the anti-invasive mechanism of matrine in lung cancer. Therefore, we tried to investigate the molecular mechanism of matrine on the invasive ability of NSCLC cells in vitro. Cell Counting Kit-8 assay was used to evaluate the cell viability. Transwell assay was used to detect the migration and invasion abilities. Microarray assay was used to analyze the differentiated expression genes with or without matrine treatment. Western blotting and real-time polymerase chain reaction were applied to detect the expressions of PAX2, E-cadherin and N-cadherin. Our study showed that matrine could suppress the proliferative activity of NSCLC cells in a dose- and time-dependent manner. Further investigation discovered that the migration and invasion of NSCLC cells were significantly inhibited by treatment with different concentrations of matrine. Microarray assay, real-time polymerase chain reaction and western blotting showed that matrine could significantly decrease the expression of PAX2. In addition, epithelial-mesenchymal transition and related proteins were decreased. In conclusion, matrine may block PAX2 expression to interfere with epithelial-mesenchymal transition signaling pathway that ultimately inhibit the migration and invasion of NSCLC cells in vitro. Matrine might serve as a potential agent for NSCLC treatment.

Niclosamide enhances the antitumor effects of radiation by inhibiting the hypoxia-inducible factor-1α/vascular endothelial growth factor signaling pathway in human lung cancer cells.

Lung cancer is one of the leading causes of cancer-associated mortality, worldwide. The overall survival rate remains low, but progress has been made in improving the diagnosis and treatment of lung cancer over the past decades. Niclosamide, a salicylanilide derivative used for the treatment of tapeworm infections, is safe, well tolerated, inexpensive and readily available. Previous studies have identified niclosamide as a potential anticancer agent. The present study demonstrated that niclosamide enhanced the effect of irradiation by inhibiting the hypoxia-inducible factor-1α/vascular endothelial growth factor signaling pathway. These findings suggest that niclosamide may be a promising candidate for clinical evaluation as part of a combined regimen for the treatment of non-small cell lung cancer.

[Synergistic Antitumor Effect of Amorphigenin Combined with Cisplatin in Human Lung Adenocarcinoma A549/DDP Cells].

BACKGROUND: Amorphigenin, a rotenoid compouns, from seeds of Amorpha fruticosa, has been shown to possess anti-proliferation activities in several cancer cells. To explore the antitumor effects of amorphigenin on cisplatin-resistant human lung adenocarcinoma A549/DDP cells and explore the underlying mechanisms. METHODS: CCK-8 assay was used to measure the proliferation of A549/DDP cells; Colony formation assay was used to measure the colony formation of A549/DDP cells; Flow cytometry assay was used to detect the apoptosis rates; Western blot analysis was used to explore the expression of apoptosis-related proteins (caspase-3 protein, PARP protein) and lung resistance protein (LRP). RESULTS: Our results demonstrated that amorphigenin could inhibit the proliferation of A549/DDP cells with a inhibition concentration of 50% cell growth (IC50) at 48 h of (2.19±0.92) µmol/L. Amorphigenin could inhibit the colony formation ability and induce apoptosis of A549/DDP cells; Furthermore, amorphigenin combined with cisplatin showed synergistic proliferation-inhibitory effect and apoptosis-promoting effect in A549/DDP cells; reduced the expression of LRP of A549/DDP cells. CONCLUSIONS: Amorphigenin remarkably inhibits the proliferation and induces apoptosis in A549/DDP cells. Combination of amorphigenin with cisplatin had the synergistic inhibitory effect on A549/DDP cells by downregulating the expression of LRP.
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Overexpression of the regulator of G-protein signaling 5 reduces the survival rate and enhances the radiation response of human lung cancer cells.

Regulator of G protein signaling 5 (RGS5) belongs to the R4 subfamily of RGS proteins, a family of GTPase activating proteins, which is dynamically regulated in various biological processes including blood pressure regulation, smooth muscle cell pathology, fat metabolism and tumor angiogenesis. Low-expression of RGS5 was reported to be associated with tumor progression in lung cancer. In the present study, we examined the potential roles of RGS5 in human lung cancer cells by overexpressing RGS5 in the cancer cells and further explored the underlying molecular mechanisms. The RGS5 gene was cloned and transfected into the human lung cancer cell lines A549 and Calu-3. The cells were tested for apoptosis with flow cytometry, for viability with MTT, for mobility and adhesion capacity. The radiosensitization effect of RGS5 was measured by a colony formation assay. The mechanisms of RGS5 functioning was also investigated by detection of protein expression with western blot analysis, including PARP, caspase 3 and 9, bax, bcl2, Rock1, Rock2, CDC42, phospho-p53 (Serine 15) and p53. The present study demonstrated that RGS5 overexpression remarkably induced apoptosis in human lung cancer cells, which was suggested to be through mitochondrial mechanisms. Overexpression of RGS5 resulted in significantly lower adhesion and migration abilities of the lung cancer cells (P<0.01). Furthermore, overexpression of RGS5 sensitized the lung cancer cells to radiation. In conclusion, the present study showed that RGS5 played an inhibitory role in human lung cancer cells through induction of apoptosis. Furthermore, RGS5 enhanced the cytotoxic effect of radiation in the human lung cancer cells. Our results indicated that RGS5 may be a potential target for cancer therapy.

Antisense oligonucleotides targeting human telomerase mRNA increases the radiosensitivity of nasopharyngeal carcinoma cells.

Nasopharyngeal carcinoma (NPC) is associated with a high incidence rate in South China and is predominantly treated with radiotherapy; however, the survival rate remains low. The therapeutic effects of radiation and chemotherapy may be enhanced when combined with anti­sense oligonucleotides targeting human telomerase RNA (hTR ASODN). However, the influence of hTR ASODN on the anti­tumor effects of radiation in NPC remain unknown. The present study investigated the effects of hTR ASODN on the proliferation and radiosensitivity of NPC cells, and further explored the underlying mechanisms. hTR ASODN significantly inhibited the proliferation and decreased the telomere length of CNE­2 human NPC cells. Furthermore, combined treatment of hTR ASODN with radiation significantly enhanced anti­tumor efficacy. The apoptotic rate and cleavage of caspase 9 were increased in the cells treated with the combined therapy, as compared with the cells treated with hTR ASODN or radiotherapy alone. In conclusion, these results suggest that hTR ASODN may inhibit the proliferation of NPC cells and enhance the anti­tumor effects of radiation by inducing cell apoptosis. Therefore hTR ASODN may be a potential adjuvant agent for the treatment of NPC combined with radiation therapy, and these findings are of translational importance.

Metformin inhibits the growth of nasopharyngeal carcinoma cells and sensitizes the cells to radiation via inhibition of the DNA damage repair pathway.

Nasopharyngeal carcinoma (NPC) is a leading cause of cancer-related mortality. Radiotherapy is one of the primary modalities for NPC treatment. However, in patients in the late stages of the disease, the local control rate and overall survival rate remain low. Therefore, it is urgent to identify new targets that can improve the outcome of radiotherapy in this neoplasm. In the present study, we investigated the effects of metformin on the radiosensitivity of NPC cells and explored the potential mechanisms. The radiosensitizing effects of metformin on NPC cells were measured by colony formation assay. Cell apoptosis was assessed by Hoechst 33342 staining analysis. DNA damage was detected by monitoring γ-H2AX foci with immunofluorescence. The changes in apotosis-related and DNA damage repair-related proteins were detected by western blotting. Our study demonstrated that metformin significantly reduced the cell viability, enhanced radiosensitivity and potentiated radiation-induced caspase-9/-3 cleavage in the NPC cells. In addition, metformin plus radiation significantly upregulated the expression of p-ATM, p-ATR, γ-H2AX and downregulated the expression of ATM, ATR, p95/NBS1, Rad50, DNA-PK, Ku70 and Ku80. Therefore, our results suggest that metformin possesses a strong radiosensitizing potential in NPC cells. This radiosensitizing effect was associated with inhibition of DNA double-strand break repair processes through HR repair and the NHEJ repair signaling pathway, thereby enhancing radiation-induced cell apoptosis. These findings imply that metformin is a potent radiation-sensitizing agent and may be a promising candidate for clinical evaluation as part of a combined regimen for the treatment of nasopharyngeal carcinoma.

A new version of targeted minicircle producer system for EBV-positive human nasopharyngeal carcinoma.

Targeted gene therapy needs to be implemented for future therapies to ensure efficient activity at the site of patient primary tumors or metastases without causing intolerable side-effects. One of the elements of gene therapy is vector, which includes viral and non-viral vector. In the present study, we constructed a novel non-viral targeted gene therapeutic system by using the new minicircle (MC) producing plasmid for Epstein-Barr virus (EBV)-positive nasopharyngeal carcinoma (NPC). Molecular cloning technique was used to construct plasmids and electrophoretic analysis. Dual-luciferase reporter assay was used to evaluate the expression of luciferase. Fluorescence microscope was used to detect the expression of enhanced green fluorescence protein (EGFP). We constructed a new MC producing system pMC.BESPX-origin of plasmid replication (oriP), and demonstrated that this system could produce highly purified MC-oriP. Furthermore, our results showed that MC-oriP vector produced by the new system could mediate targeted luciferase gene expression in EBV-positive NPC cells. In addition, we verified that MC could mediate enhanced transgene expression compared with parent plasmid through EGFP transfection. The present study constructed a targeted expression vector pMC.BESPX-oriP which could carry diversified therapeutic genes for EBV-positive NPC and provides a new approach for MC-based therapies.

Genetic and epigenetic down-regulation of microRNA-212 promotes colorectal tumor metastasis via dysregulation of MnSOD.

BACKGROUND & AIMS: Altered functions of microRNAs (miRNAs) have been associated with colorectal cancer (CRC). miR-212 is transcribed from a stable intron of a non-protein coding gene, and is reportedly down-regulated in different tumor types. We investigated the role of miR-212 in colorectal carcinogenesis and progression. METHODS: We analyzed the expression of miR-212 by real-time polymerase chain reaction (PCR) analysis of colorectal cell lines and 180 paired tumor samples and surrounding healthy tissue. We overexpressed and knocked down miR-212 in CRC cell lines and assessed the in vitro effects. We also studied the effects of miR-212 overexpression on metastasis of tumors grown from HCT116 cells in nude mice. RESULTS: Overexpression of miR-212 inhibited CRC cell migration and invasion in vitro and formation of intrahepatic and pulmonary metastasis in vivo. We identified manganese superoxide dismutase (MnSOD) messenger RNA as a direct target of miR-212, and observed an inverse correlation between the level of miR-212 and MnSOD protein in colorectal tumor samples. MnSOD was required for down-regulation of epithelial markers and up-regulation of mesenchymal markers in CRC cells, indicating that it promoted the epithelial-mesenchymal transition. Overexpression of miR-212 reduced the levels of MnSOD to block the epithelial-mesenchymal transition process. Loss of heterozygosity and promoter hypermethylation each contributed to the down-regulation of miR-212. Reduced levels of miR-212 were associated with a more aggressive tumor phenotype and short disease-free survival times of patients (P = .0045; overall survival, P = .0015). CONCLUSIONS: miR-212 is down-regulated in human CRC tissues via genetic and epigenetic mechanisms. miR-212 might prevent tumor progression by targeting MnSOD messenger RNA; reduction of miR-212 could be a prognostic marker for patients with CRC. miR-212 and MnSOD might also be therapeutic targets for cancer.

AC133 expression associated with poor prognosis in stage II colorectal cancer.

Identification of high-risk prognostic markers for stage II colorectal cancer (CRC) is currently a big challenge. CD133 is one of the most commonly used CRC stem cell markers. However, its specificity is controversial. Recent studies have demonstrated that the AC133 epitope of CD133, not the CD133 protein, is responsible for cancer stem cell identification. The aim of this study was to investigate the clinical significance of AC133 expression in stage II CRC. Two antibodies against CD133, including AC133 and Ab19898, were compared for their expression characteristics. AC133 was chosen for further immunohistochemical assessment on 176 stage II CRC primary tumors with at least 12 examined lymph nodes. The cutoff value for positive rate of AC133 expression was determined by ROC curve analysis. AC133 was analyzed for correlations with clinicopathological and prognostic parameters. The results indicated that AC133 was negative in adjacent noncancerous colorectal mucosa while positive in 116 cases (65.9 %) of primary tumors. AC133 expression was significantly correlated with preoperative serum carcinoembryonic antigen level (p = 0.006) and tumor differentiation grade (p = 0.019). Furthermore, high AC133 expression was identified as a significant predictor for poor disease-free survival and overall survival at both univariate (p = 0.009, 0.013, respectively) and multivariate levels (p = 0.022, 0.026, respectively). Our data suggest that AC133 is an independent adverse prognostic factor and a potential marker for survival classification in stage II CRC patients.

Recombinant human endostatin normalizes tumor vasculature and enhances radiation response in xenografted human nasopharyngeal carcinoma models.

BACKGROUND: Hypoxic tumor cells can reduce the efficacy of radiation. Antiangiogenic therapy may transiently "normalize" the tumor vasculature to make it more efficient for oxygen delivery. The aim of this study is to investigate whether the recombinant human endostatin (endostar) can create a "vascular normalization window" to alleviate hypoxia and enhance the inhibitory effects of radiation therapy in human nasopharyngeal carcinoma (NPC) in mice. METHODOLOGY/PRINCIPAL FINDINGS: Transient changes in morphology of tumor vasculature and hypoxic tumor cell fraction in response to endostar were detected in mice bearing CNE-2 and 5-8F human NPC xenografts. Various treatment schedules were tested to assess the influence of endostar on the effect of radiation therapy. Several important factors relevant to the angiogenesis were identified through immunohistochemical staining. During endostar treatment, tumor vascularity decreased, while the basement membrane and pericyte coverage associated with endothelial cells increased, which supported the idea of vessel normalization. Hypoxic tumor cell fraction also decreased after the treatment. The transient modulation of tumor physiology caused by endostar improved the effect of radiation treatment compared with other treatment schedules. The expressions of vascular endothelial growth factor (VEGF), matrix metalloproteinase-2 (MMP-2), MMP-9, and MMP-14 decreased, while the level of pigment epithelium-derived factor (PEDF) increased. CONCLUSIONS: Endostar normalized tumor vasculature, which alleviated hypoxia and significantly sensitized the function of radiation in anti-tumor in human NPC. The results provide an important experimental basis for combining endostar with radiation therapy in human NPC.