Metal-proteinase ADAM12, kinesin 14 and checkpoint suppressor 1 as new molecular markers of laryngeal carcinoma

FOXN3 inhibits the progression of ovarian cancer through negatively regulating the expression of RPS15A

Ovarian cancer is the second most common cause of gynecological cancer death and has a high recurrence rate. FOXN3, a transcription inhibitor belonging to FOX family, has anti-tumor effects on several cancers. Bioinformatics analysis revealed that the expression of FOXN3 was downregulated in ovarian cancer specimens. However, the role of FOXN3 in ovarian cancer remains unclear. Herein, we investigated the role of FOXN3 in ovarian cancer using OVCAR3 and A2780 cells. Flow cytometry and CCK-8 analysis showed that overexpression of FOXN3 inhibited the proliferation and cell cycle progression of OVCAR3 cells. Cell invasion and migration abilities were decreased by FOXN3 according to transwell and wound healing assays. The suppression of FOXN3 on angiogenesis in OVCAR3 cells was evidenced by reduced vessel formation and VEGFA protein expression. Taken together, FOXN3 had an inhibitory effect on the proliferation, migration, invasion and angiogenesis of OVCAR3 cells, while its knockdown exhibited an opposite effect in A2780 cells. By inoculation of FOXN3-overexpressing cells into nude mice, tumorigenesis assay demonstrated that FOXN3 could delay the growth of ovarian cancer cells in vivo. The interaction between FOXN3 and RPS15A was preliminarily explored via dual-luciferases assay and ChIP. FOXN3 was confirmed to bind to the promoter (at - 1588/- 1581 and - 1476/- 1467) of gene RPS15A and inhibit its transcriptional expression. We further found that overexpression of RPS15A diminished the inhibition of FOXN3 on ovarian cancer cell malignant behaviors. These findings indicate that FOXN3 negatively regulates the expression of RPS15A and thus suppresses the progression of ovarian cancer.

KIF14 affects cell cycle arrest and cell viability in cervical cancer by regulating the p27Kip1 pathway

Background

Cervical cancer is a kind of malignant gynecological tumor. The first choice for treating cervical cancer is still a combination of surgery and chemoradiotherapy, but the 5-year survival rate remains poor. Therefore, researchers are trying to find new ways to diagnose and treat cervical cancer early.

Methods

The expression level of KIF14 in cells and tissues was determined via qRT–PCR. The ability of the cells to proliferate, migrate, and invade was examined using CCK-8 assay kits, colony formation assays, and Transwell chambers. The expression levels of Cyclin D1, Cyclin B1, p21, and p27 were also detected using western blot assays.

Results

The results suggested that p27 is a key regulatory factor in the KIF14-mediated regulation of the cell cycle. In addition, KIF14 knockdown promotes malignancy in cervical cancer cells by inhibiting p27 degradation, resulting in cell cycle arrest.

Conclusions

KIF14 is an oncogene in cervical cancer, and knocking down KIF14 causes cell cycle arrest by inhibiting p27 degradation, thus affecting cell viability, proliferation, and migration. These results provide a potential therapeutic target for cervical cancer.

miR-29a-3p enhances the radiosensitivity of oral squamous cell carcinoma cells by inhibiting ADAM12

Oral squamous cell carcinoma (OSCC) is the most common malignant tumor in the head and neck, and radiotherapy is the main approach for this disease, while irradiation resistance is a huge challenge that influences radiosensitivity. This study aims to determine the role and function of miR-29a-3p and ADAM12 in the radiosensitivity of OSCC cells. The expression pattern of ADAM12 in OSCC cells was searched in TCGA database. The binding of miR-29a-3p and ADAM12 was predicted by Starbase and verified using dual luciferase reporter gene assay. The RNA or protein expressions of miR-29a-3p and ADAM12 were measured by RT-qPCR or western blot. OSCC cell lines were treated by various γ-ray irradiation dosages before the alteration on miR-29a-3p expression and on the cell viability, proliferation, migration and cell apoptosis was detected. ADAM12 was highly expressed in OSCC cells, whose expression in resistant cells was positively correlated with irradiation dosage. Overexpression of ADAM12 in OSCC cells lead to increased cell proliferation and migration ability as well as inhibited cell apoptosis. miRNAs potentially binding ADAM12 in PITA, microT, miRmap and targetscan were screened, among which miR-29a-3p had the maximum differential expression levels in OSCC cells determined by RT-qPCR. Overexpression of miR-29a-3p resulted in suppressed cell viability, proliferation, migration ability and increased cell apoptosis, while this expression pattern can be partially counteracted by ADAM12 overexpression in OSCC cells. miR-29a-3p through targeting and inhibiting AMDM12 enhances the radiosensitivity of OSCC cells.

Dysregulation of KIF14 regulates the cell cycle and predicts poor prognosis in cervical cancer: a study based on integrated approaches

Cervical cancer (CC) is the most common malignant tumor in females. Although persistent high-risk human papillomavirus (HPV) infection is a leading factor that causes CC, few women with HPV infection develop CC. Therefore, many mechanisms remain to be explored, such as aberrant expression of oncogenes and tumor suppressor genes. To identify promising prognostic factors and interpret the relevant mechanisms of CC, the RNA sequencing profile of CC was downloaded from the Cancer Genome Atlas and the Gene Expression Omnibus databases. The GSE63514 dataset was analyzed, and differentially expressed genes (DEGs) were obtained by weighted coexpression network analysis and the edgeR package in R. Fifty-three shared genes were mainly enriched in nuclear chromosome segregation and DNA replication signaling pathways. Through a protein-protein interaction network and prognosis analysis, the kinesin family member 14 (KIF14) hub gene was extracted from the set of 53 shared genes, which was overexpressed and associated with poor overall survival (OS) and disease-free survival (DFS) of CC patients. Mechanistically, gene set enrichment analysis showed that KIF14 was mainly enriched in the glycolysis/gluconeogenesis signaling pathway and DNA replication signaling pathway, especially in the cell cycle signaling pathway. RT-PCR and the Human Protein Atlas database confirmed that these genes were significantly increased in CC samples. Therefore, our findings indicated the biological function of KIF14 in cervical cancer and provided new ideas for CC diagnosis and therapies.

miR-611 promotes the proliferation, migration and invasion of tongue squamous cell carcinoma cells by targeting FOXN3

OBJECTIVES

The function of miR-611 has not yet been reported. We aimed to investigate the effects of miR-611 on tongue squamous cell carcinoma (TSCC) and the underlying mechanism.

MATERIALS AND METHODS

The expression level of miR-611 in TSCC tissues was measured using quantitative reverse transcriptase-polymerase chain reaction (RT-qPCR). Cell proliferation, migration and invasion were examined by performing CCK-8, IncuCyte and Transwell assays. Bioinformatics analyses and microarrays were used to screen for target genes, which were verified using a luciferase reporter assay, RT-qPCR and Western blotting. The xenograft model was used to assess the effects of miR-611 in vivo.

RESULTS

miR-611 was upregulated in TSCC tissues, which was significantly correlated with TNM stage and negatively associated with the overall survival of patients. In addition, upregulation of miR-611 not only potentiated the proliferation, migration, invasion and epithelial-mesenchymal transition (EMT) of TSCC cells in vitro, but also promoted tumour growth in vivo. FOXN3 was identified as a candidate target gene of miR-611 and subsequently verified. Finally, miR-611 induced a malignant phenotype of TSCC, which was rescued by overexpression of FOXN3.

CONCLUSIONS

Our findings suggest that miR-611 is a novel therapeutic target for TSCC.

Recent Advances in Understanding FOXN3 in Breast Cancer, and Other Malignancies

FOXN3 (forkhead box N3; CHES1: check point suppressor 1) belongs to the forkhead box (FOX) protein family. FOXN3 displays transcriptional inhibitory activity, and is involved in cell cycle regulation and tumorigenesis. FOXN3 is a tumor suppresser and alterations in FOXN3 are found in of a variety of cancers including melanoma, osteosarcoma, and hepatocellular carcinoma. While the roles of FOXN3 role in some cancers have been explored, its role in breast cancer remains unclear. Here we describe current state of knowledge of FOXN3 functions, and focus on its roles (known and potential) in breast cancer.

The histone H3 lysine-27 demethylase UTX plays a critical role in colorectal cancer cell proliferation

Background

Ubiquitously transcribed tetratricopeptide repeat, X chromosome (UTX) is an H3K27me3 demethylase, a permissive mark associated with active gene transcription. UTX has been linked to various human cancers. Colorectal cancer (CRC) ranks 3rd among the most common cancers worldwide. However, the role of UTX in colorectal cancer has rarely been reported.

Methods

RT-qPCR, immunoblotting assays (WB), and immunohistochemistry staining were conducted to explore the UTX expression levels in CRC tissues and surrounding normal tissues. CCK-8 assays, colony formation assays, and flow cytometry were also used to determine the potential role of UTX in CRC cell proliferation in vitro. A cell line-derived xenograft model was performed to determine on the role of UTX in HCT116 cell proliferation in vivo. The protein expression levels of UTX, KIF14, AKT, and GAPDH were examined by WB.

Results

Compared with surrounding normal tissues, UTX was upregulated in CRC tissues. Knockdown of UTX significantly inhibited proliferation and caused G0/G1 cell cycle arrest in CRC cell lines, and overexpression of UTX significantly promoted proliferation in CRC cells. Furthermore, knockdown of UTX significantly inhibited tumour growth in vivo. In addition, knockdown of UTX decreased the expression of KIF14 and pAKT and increased the expression of P21.

Conclusions

Our findings indicate that knockdown of UTX inhibits CRC cell proliferation and causes G0/G1 cell cycle arrest through downregulating expression of KIF 14 and pAKT. Thus, UTX may serve as a novel biomarker in CRC.

Bispecific Forkhead Transcription Factor FoxN3 Recognizes Two Distinct Motifs with Different DNA Shapes

Transcription factors (TFs) control gene expression by binding DNA recognition sites in genomic regulatory regions. Although most forkhead TFs recognize a canonical forkhead (FKH) motif, RYAAAYA, some forkheads recognize a completely different (FHL) motif, GACGC. Bispecific forkhead proteins recognize both motifs, but the molecular basis for bispecific DNA recognition is not understood. We present co-crystal structures of the FoxN3 DNA binding domain bound to the FKH and FHL sites, respectively. FoxN3 adopts a similar conformation to recognize both motifs, making contacts with different DNA bases using the same amino acids. However, the DNA structure is different in the two complexes. These structures reveal how a single TF binds two unrelated DNA sequences and the importance of DNA shape in the mechanism of bispecific recognition.

Observations on spontaneous tumor formation in mice overexpressing mitotic kinesin Kif14

The KIF14 locus is gained and overexpressed in various malignancies, with prognostic relevance. Its protein product, a mitotic kinesin, accelerates growth of normal mammary epithelial cells in vitro and retinoblastoma tumours in a mouse model, while KIF14 knockdown blocks growth of brain, liver, ovarian, breast, prostate, and other tumour cells and xenografts. However, the tumour-initiating effects of Kif14 overexpression have not been studied. We aged a cohort of Kif14-overexpressing transgenic mice and wild-type littermates and documented survival, cause of death, and tumour burden. The Kif14 transgene was expressed in all tissues examined, and was associated with increased proliferation marker expression. Neither mouse weights nor overall survival differed between genotypes. However, Kif14 transgenic mice showed a higher incidence of fatal lymphomas (73 vs. 50%, p = 0.03, Fisher’s exact test), primarily follicular and diffuse B-cell lymphomas. Non-tumour findings included a bilateral ballooning degeneration of lens in 12% of Kif14 transgenic mice but no wild-type mice (p = 0.02). Overall, this work reveals a novel association of Kif14 overexpression with lymphoma but suggests that Kif14 does not have as prominent a role in initiating cancer in other cell types as it does in accelerating tumour development in response to other oncogenic insults.

Overexpression of a novel candidate oncogene KIF14 correlates with tumor progression and poor prognosis in prostate cancer

Prostate cancer (PCa) is the second leading cause of death from cancer in men. The mechanism underlying tumorigenesis and development of PCa is largely unknown. Here, we identified Kinesin family member 14 (KIF14) as a novel candidate oncogene in PCa. We found that KIF14 was overexpressed in multiple PCa cell lines and primary PCa tissues. Knockdown of KIF14 in DU145 and PC3 prostate cancer cells suppressed cell proliferation, induced cell cycle arrest and apoptosis. Transcriptome analysis by RNA-sequencing demonstrated that KIF4 suppression led to transcriptional changes of genes involved in p53 and TGF-beta signaling pathway. In addition, upregulated expression of GADD45A, GADD45B, p21, PIDD and Shisa5, which contribute to growth arrest and apoptosis induction, and downregulated CCNB1 that promotes cell cycle progression were confirmed by quantitative real-time PCR after KIF4 knockdown. We further found that KIF14 protein level was positively correlated with T stage and Gleason Score. Patients with higher KIF14 expression had shorter overall survival time than those with lower KIF14 expression. Thus, our data indicate that KIF14 could act as a potential oncogene that contributes to tumor progression and poor prognosis in PCa, which may represent a novel and useful prognostic biomarker for PCa.

Loss of FOXN3 in colon cancer activates beta-catenin/TCF signaling and promotes the growth and migration of cancer cells

Aberrant activation of beta-catenin/TCF is a hallmark of colon cancer. How the functions of nuclear localized beta-catenin are regulated is not fully understood. Here, it was found that FOXN3 (Forkhead box N3) was down-regulated in colon cancer tissues. Forced expression of FOXN3 inhibited the growth, migration and invasion of colon cancer cells, while knocking down the expression of FOXN3 promoted the growth, migration, invasion and metastasis of colon cancer cells. FOXN3 bind to beta-catenin and inhibited beta-catenin/TCF signaling by blocking the interaction between beta-catenin and TCF4. Taken together, these data demonstrated the suppressive roles of FOXN3 in the progression of colon cancer, and indicated that restoring the functions of FOXN3 would be a novel therapeutic strategy for colon cancer.

The transcription factor FOXN3 inhibits cell proliferation by downregulating E2F5 expression in hepatocellular carcinoma cells

Hepatocellular carcinoma (HCC) is the second leading cause of cancer-related death worldwide, and the mechanisms underlying the development of HCC remain to be elucidated. Forkhead box N3 (FOXN3) is an important member of the FOX family of transcription factors that plays an essential role in several cancers but has not been investigated in HCC. In this study, we demonstrate that FOXN3 is downregulated in human primary HCC tissues compared with their matched adjacent liver tissues. Functional tests of FOXN3 demonstrated that FOXN3 inhibits the proliferation of HCC cells in vitro and in vivo. Additionally, FOXN3 repressed the mRNA and protein expression of E2F5, a reported potential oncogene, by inhibiting the promoter activity of E2F5. Collectively, our findings indicate that FOXN3 functions as a tumor suppressor in HCC by downregulating the expression of E2F5.

Neuroblastoma cells depend on HDAC11 for mitotic cell cycle progression and survival

The number of long-term survivors of high-risk neuroblastoma remains discouraging, with 10-year survival as low as 20%, despite decades of considerable international efforts to improve outcome. Major obstacles remain and include managing resistance to induction therapy, which causes tumor progression and early death in high-risk patients, and managing chemotherapy-resistant relapses, which can occur years after the initial diagnosis. Identifying and validating novel therapeutic targets is essential to improve treatment. Delineating and deciphering specific functions of single histone deacetylases in neuroblastoma may support development of targeted acetylome-modifying therapeutics for patients with molecularly defined high-risk neuroblastoma profiles. We show here that HDAC11 depletion in MYCN-driven neuroblastoma cell lines strongly induces cell death, mostly mediated by apoptotic programs. Genes necessary for mitotic cell cycle progression and cell division were most prominently enriched in at least two of three time points in whole-genome expression data combined from two cell systems, and all nine genes in these functional categories were strongly repressed, including CENPA, KIF14, KIF23 and RACGAP1. Enforced expression of one selected candidate, RACGAP1, partially rescued the induction of apoptosis caused by HDAC11 depletion. High-level expression of all nine genes in primary neuroblastomas significantly correlated with unfavorable overall and event-free survival in patients, suggesting a role in mediating the more aggressive biological and clinical phenotype of these tumors. Our study identified a group of cell cycle-promoting genes regulated by HDAC11, being both predictors of unfavorable patient outcome and essential for tumor cell viability. The data indicate a significant role of HDAC11 for mitotic cell cycle progression and survival of MYCN-amplified neuroblastoma cells, and suggests that HDAC11 could be a valuable drug target.

Kinesin family member 14 in human oral cancer: A potential biomarker for tumoral growth

Kinesin family member 14 (KIF14), a microtubule-based motor protein, plays an important role in chromosomal segregation, congression, and alignment. Considerable evidence indicates that KIF14 is involved in cytokinesis, although little is known about its role in oral squamous cell carcinomas (OSCCs). In the current study, we functionally and clinically investigated KIF14 expression in patients with OSCC. Quantitative reverse transcriptase–polymerase chain reaction and immunoblotting analyses were used to assess the KIF14 regulatory mechanism in OSCC. Immunohistochemistry (IHC) was performed to analyze the correlation between KIF14 expression and clinical behavior in 104 patients with OSCC. A KIF14 knockdown model of OSCC cells (shKIF14 cells) was used for functional experiments. KIF14 expression was up-regulated significantly (P<0.05) in OSCCs compared with normal counterparts in vitro and in vivo. In addition, shKIF14 cells inhibited cellular proliferation compared with control cells by cell-cycle arrest at the G2/M phase through up-regulation of G2 arrest-related proteins (p-Cdc2 and cyclin B1). As expected, IHC data from primary OSCCs showed that KIF14-positive patients exhibited significantly (P<0.05) more larger tumors compared with KIF14-negative patients. The current results suggest for the first time that KIF14 is an indicator of tumoral size in OSCCs and that KIF14 might be a potential therapeutic target for development of new treatments for OSCCs.

ADAM12 is a prognostic factor associated with an aggressive molecular subtype of high-grade serous ovarian carcinoma

ADAM metallopeptidase domain 12 (ADAM12) is a promising biomarker because of its low expression in normal tissues and high expression in a variety of human cancers. However, ADAM12 levels in ovarian cancer have not been well characterized. We previously identified ADAM12 as one of the signature genes associated with poor survival in high-grade serous ovarian carcinoma (HGSOC). Here, we sought to determine if high levels of the ADAM12 protein and/or messenger RNA (mRNA) are associated with clinical variables in HGSOC. We show that high protein levels of ADAM12 in banked preoperative sera are associated with shorter progression-free and overall survival. Tumor levels of ADAM12 mRNA were also associated with shorter progression-free and overall survival as well as with lymphatic and vascular invasion, and residual tumor volume following cytoreductive surgery. The majority of genes co-expressed with ADAM12 in HGSOC were transforming growth factor (TGF)β signaling targets that function in collagen remodeling and cell-matrix adhesion. In tumor sections, the ADAM12 protein and mRNA were expressed in epithelial cancer cells and surrounding stromal cells. In vitro data showed that ADAM12 mRNA levels can be increased by TGFβ signaling and direct contact between epithelial and stromal cells. High tumor levels of ADAM12 mRNA were characteristic of the mesenchymal/desmoplastic molecular subtype of HGSOC, which is known to have the poorest prognosis. Thus, ADAM12 may be a useful biomarker of aggressive ovarian cancer for which standard treatment is not effective.

Transcriptional and epigenetic regulation of KIF14 overexpression in ovarian cancer

KIF14 (kinesin family member 14) is a mitotic kinesin and an important oncogene in several cancers. Tumor KIF14 expression levels are independently predictive of poor outcome, and in cancer cells KIF14 can modulate metastatic behavior by maintaining appropriate levels of cell adhesion and migration proteins at the cell membrane. Thus KIF14 is an exciting potential therapeutic target. Understanding KIF14's regulation in cancer cells is crucial to the development of effective and selective therapies to block its tumorigenic function(s). We previously determined that close to 30% of serous ovarian cancers (OvCa tumors) exhibit low-level genomic gain, indicating one mechanism of KIF14 overexpression in tumors. We now report on transcriptional and epigenetic regulation of KIF14. Through promoter deletion analyses, we identified one cis-regulatory region containing binding sites for Sp1, HSF1 and YY1. siRNA-mediated knockdown of these transcription factors demonstrated endogenous regulation of KIF14 overexpression by Sp1 and YY1, but not HSF1. ChIP experiments confirmed an enrichment of both Sp1 and YY1 binding to the endogenous KIF14 promoter in OvCa cell lines with high KIF14 expression. A strong correlation was seen in primary serous OvCa tumors between Sp1, YY1 and KIF14 expression, further evidence that these transcription factors are important players in KIF14 overexpression. Hypomethylation patterns were observed in primary serous OvCa tumors, suggesting a minor role for promoter methylation in the control of KIF14 gene expression. miRNA expression analysis determined that miR-93, miR-144 and miR-382 had significantly lower levels of expression in primary serous OvCa tumors than normal tissues; treatment of an OvCa cell line with miRNA mimics and inhibitors specifically modulated KIF14 mRNA levels, pointing to potential novel mechanisms of KIF14 overexpression in primary tumors. Our findings reveal multiple mechanisms of KIF14 upregulation in cancer cells, offering new targets for therapeutic interventions to reduce KIF14 in tumors, aiming at improved prognosis.

CHES1/FOXN3 regulates cell proliferation by repressing PIM2 and protein biosynthesis

The expression of the forkhead transcription factor checkpoint suppressor 1 (CHES1), also known as FOXN3, is reduced in many types of cancers. We show here that CHES1 decreases protein synthesis and cell proliferation in tumor cell lines but not in normal fibroblasts. Conversely, short hairpin RNA-mediated depletion of CHES1 increases tumor cell proliferation. Growth suppression depends on the CHES1 forkhead DNA-binding domain and correlates with the nuclear localization of CHES1. CHES1 represses the expression of multiple genes, including the kinases PIM2 and DYRK3, which regulate protein biosynthesis, and a number of genes in cilium biogenesis. CHES1 binds directly to the promoter of PIM2, and in cells expressing CHES1 the levels of PIM2 are reduced, as well as the phosphorylation of the PIM2 target 4EBP1. Overexpression of PIM2 or eIF4E partially reverses the antiproliferative effect of CHES1, indicating that PIM2 and protein biosynthesis are important targets of the antiproliferative effect of CHES1. In several human hematopoietic cancers, CHES1 and PIM2 expressions are inversely correlated, suggesting that repression of PIM2 by CHES1 is clinically relevant.

The genomic landscape of retinoblastoma: a review

Retinoblastoma is a paediatric ocular tumour that continues to reveal much about the genetic basis of cancer development. Study of genomic aberrations in retinoblastoma tumours has exposed important mechanisms of cancer development and identified oncogenes and tumour suppressors that offer potential points of therapeutic intervention. The recent development of next-generation genomic technologies has allowed further refinement of the genomic landscape of retinoblastoma at high resolution. In a relatively short period of time, a wealth of genetic and epigenetic data has emerged on a small number of tumour samples. These data highlight the inherent molecular complexity of this cancer despite the fact that most retinoblastomas are initiated by the inactivation of a single tumour suppressor gene. This review outlines the current understanding of the genomic, genetic and epigenetic changes in retinoblastoma, highlighting recent genome-wide analyses that have identified exciting candidate genes worthy of further validation as potential prognostic and therapeutic targets.

MicroRNA-574-5p was pivotal for TLR9 signaling enhanced tumor progression via down-regulating checkpoint suppressor 1 in human lung cancer

Accumulating data suggested that functional expression of Toll-like receptors (TLRs) in tumor cells was involved in tumor progression. Our previous study demonstrated that TLR9 signaling could enhance the tumor progression of human lung cancer cells in vitro and in vivo. We further showed that miR-574-5p was the mostly up-regulated miRNA in human lung cancer cells under TLR9 signaling by miRNA array analysis. Here we characterized the potential role of miRNA-574-5p in enhanced tumor progression induced by TLR9 signaling in human lung cancer. We confirmed that TLR9 signaling effectively elevated the expression of miR-574-5p in human lung cancer cells. Notably, we found that down-regulation of miRNA-574-5p using miR-574-5p inhibitor in vitro or miR-574-5p sponge in vivo significantly abrogated the enhanced tumor progression induced by TLR9 signaling. Further studies showed that miR-574-5p was an important player associated with enhanced tumor progression of human lung cancer cells. Notably, we identified checkpoint suppressor 1 (Ches1) as the dominant direct target for miRNA-574-5p to confer the TLR9 signaling enhanced tumor progression. We revealed that over-expression of Ches1 significantly inhibited the cell cycle entry of human lung cancer cells. Finally, we revealed that the expression of miR-574-5p was positively correlated with TLR9 and reversely correlated with Ches1 in lung cancer patients. Our findings not only facilitated the further understanding of the crosstalk between miRNAs and TLRs in tumor biology, but also provided novel potential candidates for treatment of cancer.

Kinesin family member 14 is a candidate prognostic marker for outcome of glioma patients

BACKGROUND & AIM

Human kinesin superfamily proteins (KIFs) are a conserved class of microtubule-dependent molecular motor proteins with adenosine triphosphatase activity and motion characteristics. As a member of KIFs, KIF14 plays an important role in the regulation of cell cycle and mitotic progression. Deregulation of KIF14 has been found in several human malignancies and also has been demonstrated to be involved in tumor progression and related to patient survival. The aim of this study was to investigate the clinicopathological significance of KIF14 expression in glioma.

METHODS

Real-time quantitative RT-PCR assay was performed to detect KIF14 mRNA expression, and Western blot and immunohistochemistry analyses were performed to detect KIF14 protein expression in human gliomas and non-neoplastic brain tissues, respectively. Then, the association of KIF14 immunostaining with clinicopathological factors and prognosis of glioma patients was also statistically analyzed.

RESULTS

KIF14 mRNA and protein expression were respectively increased 5.5- and 4.2-fold on average in glioma tissues relative to non-neoplastic brain tissues (both P < 0.001). Additionally, both KIF14 mRNA and protein expression increased with ascending pathological grade. Then, the high KIF14 immunostaining in glioma tissues was significantly associated with advanced pathological grade (P = 0.008), low Karnofsky performance score (KPS) (P = 0.02), high mitotic index (P = 0.005) and Ki-67 index (P = 0.008). Furthermore, both univariate and multivariate Cox regression analyses determined that KIF14 overexpression effectively predicted decreased overall survival in patients with gliomas.

CONCLUSIONS

These findings offer the first convinced evidence that KIF14 expression in gliomas is tumor-specific and increased in more aggressive tumors. KIF14 might function as a candidate prognostic marker for human gliomas.

Identification and validation of gene expression models that predict clinical outcome in patients with early-stage laryngeal cancer

BACKGROUND

Despite improvement in therapeutic techniques, patients with early-stage laryngeal cancer still recur after treatment. Gene expression prognostic models could suggest which of these patients would be more appropriate for testing adjuvant strategies.

MATERIALS AND METHODS

Expression profiling using whole-genome DASL arrays was carried out on 56 formalin-fixed paraffin-embedded tumor samples of patients with early-stage laryngeal cancer. We split the samples into a training and a validation set. Using the supervised principal components survival analysis in the first cohort, we identified gene expression profiles that predict the risk of recurrence. These profiles were then validated in an independent cohort.

RESULTS

Gene models comprising different number of genes identified a subgroup of patients who were at high risk of recurrence. Of these, the best prognostic model distinguished between a high- and a low-risk group (log-rank P<0.005). The prognostic value of this model was reproduced in the validation cohort (median disease-free survival: 38 versus 161 months, log-rank P=0.018), hazard ratio=5.19 (95% confidence interval 1.14-23.57, P<0.05).

CONCLUSIONS

We have identified gene expression prognostic models that can refine the estimation of a patient's risk of recurrence. These findings, if further validated, should aid in patient stratification for testing adjuvant treatment strategies.

Downregulation of Ches1 and other novel genes in oral cancer cells chronically exposed to areca nut extract

BACKGROUND

This study was undertaken to identify the genes in response to areca nut extract, a potential carcinogen of oral cancer.

METHODS

Two oral cancer sublines chronically treated with areca nut extract were established. Methods such as microarray and immunohistochemistry were used to screen and validate the genes' altered expressions in areca nut extract-sublines or in cancer tissues.

RESULTS

A total of 35 genes were differentially expressed in both sublines. Several functional pathways were significantly altered. Six genes were confirmed over 2-fold of changes, including Ches1. Functional analyses showed that overexpression of Ches1 suppressed cell growth and arrested cells in the G2/M phase. Consistently, this gene has reduced expression in 52% of oral cancer tissues, which was significantly correlated with the areca nut chewing habit of patients (p = .04).

CONCLUSION

We identified 35 candidates and validated 6 genes that may be associated with areca nut-induced oral cancer. Loss of Ches1 may be attributed to areca nut extract-induced oral carcinogenesis.

Forkhead transcription factors: key players in health and disease

Forkhead box (FOX) proteins constitute an evolutionarily conserved family of transcription factors with a central role not only during development, but also in the adult organism. Thus, the misregulation and/or mutation of FOX genes often induce human genetic diseases, promote cancer or deregulate ageing. Indeed, germinal FOX gene mutations cause diseases ranging from infertility to language and/or speech disorders and immunological defects. Moreover, because of their central role in signalling pathways and in the regulation of homeostasis, somatic misregulation and/or mutation of FOX genes are associated with cancer. FOX proteins have undergone diversification in terms of their sequence, regulation and function. In addition to dedicated roles, evidence suggests that Forkhead factors have retained some functional redundancy. Thus, combinations of slightly defective alleles might induce disease phenotypes in humans, acting as quantitative trait loci. Uncovering such variants would be a big step towards understanding the functional interdependencies of different FOX members and their implications in complex pathologies.

Clinical significance of genome-wide minimally deleted regions in oral squamous cell carcinomas

Oral squamous cell carcinoma (OSCC) has the highest rate of increase among male cancers in Taiwan. An understanding of the molecular pathogenesis of this disease as well as the development of prognostic markers for the clinical management of this disease is very important. Thus, a systematic loss of heterozygosity (LOH) analysis was performed to define minimally deleted regions (MDRs) in 63 male OSCCs using 400 polymorphic microsatellite markers. For increasing reliability, genomic DNA was extracted from >90% tumor cells that had been purified by LCM, and only when a microsatellite marker provided LOH information in >30% of the OSCCs was there considered to be successful allelotyping. A correlation of the various MDRs with clinicopathological parameters and prognosis was carried out. In total, 32 MDRs were identified and ten were noted as novel. In addition, six MDRs were found to be associated with cigarette smoking. Among these markers, a loss of MDR c7r2 (7q32.2-q35) was significantly associated with poor disease-free survival (DFS) and ten MDRs were associated with allelic imbalance (AI) in tumors. Among the latter, a loss of MDR c14r1 (14q24.2-q32.12) and c11r1 (11q13.4-q25) had a synergistic effect on poor DFS and were able to reduce further the DFS rate in patients with MDR c7r2 loss. Taken together, the results generated in this study provide new insights that help with exploring the molecular mechanisms associated with OSCC tumorigenesis and cigarette smoking. They also should aid the development of potential prognostic markers for the clinical management of OSCC.