Knockdown of KIF26B inhibits breast cancer cell proliferation, migration, and invasion

Fusobacterium nucleatum in tumors: from tumorigenesis to tumor metastasis and tumor resistance

Fusobacterium nucleatum, an anaerobic Gram-negative bacterium primarily residing in the oral cavity, has garnered significant attention for its emerging role in cancer progression and prognosis. While extensive research has revealed mechanistic links between Fusobacterium nucleatum and colorectal cancer, a comprehensive review spanning its presence and metastatic implications in cancers beyond colorectal origin is conspicuously absent. This paper broadens our perspective from colorectal cancer to various malignancies associated with Fusobacterium nucleatum, including oral, pancreatic, esophageal, breast, and gastric cancers. Our central focus is to unravel the mechanisms governing Fusobacterium nucleatum colonization, initiation, and promotion of metastasis across diverse cancer types. Additionally, we explore Fusobacterium nucleatum's adverse impacts on cancer therapies, particularly within the domains of immunotherapy and chemotherapy. Furthermore, this paper underscores the clinical research significance of Fusobacterium nucleatum as a potential tumor biomarker and therapeutic target, offering a novel outlook on its applicability in cancer detection and prognostic assessment.

7,8-dihydroxyflavone displayed antioxidant effect through activating HO-1 expression and inhibiting caspase-3/PARP activation in RAW264.7 cells

Flavonoids, which contain a benzo-γ-pyrone (C6-C3-C6) skeleton, have been reported to exhibit effective antioxidant ability. This study aimed to compare the antioxidant activities of 7,8-dihydroxyflavone (7,8-DHF) and 7-hydroxyflavone (7-HF) in H2 O2 , lipopolysaccharide (LPS), or tert-butyl hydroperoxide (t-BHP)-induced RAW264.7 cells, respectively. The antioxidant capacities of 7,8-DHF and 7-HF were firstly evaluated by 2,2-azinobis-3-ethyl-benzothiazoline-6-sulphonic acid (ABTS), 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP) assays. Then, reactive oxygen species (ROS), super oxide dismutase (SOD), and malondialdehyde (MDA) productions in H2 O2 , LPS, or t-BHP-induced RAW264.7 cells were tested and compared, respectively. Finally, the antioxidant mechanisms of 7-HF and 7,8-DHF were initially investigated by western blot. Our results showed that 7,8-DHF possessed stronger free-radical scavenging capacity than 7-HF. Both 7,8-DHF and 7-HF suppressed MDA production and ROS accumulation, improved the activity of SOD in H2 O2 , LPS, or t-BHP-induced RAW264.7 cells, respectively. And 7,8-DHF exerted a better antioxidant effect than 7-HF, especially in t-BHP-induced oxidative stress. Mechanically, 7,8-DHF prevented the activation of poly ADP-ribosepolymerase and caspase-3, meanwhile markedly upregulated the expression of HO-1 protein in t-BHP-induced oxidative stress. These results suggested that 7,8-DHF might serve as a potential pharmaceutical drug against oxidative stress injury.

Noncoding RNAs-based high KIF26B expression correlates with poor prognosis and tumor immune infiltration in colon cancer

BACKGROUND

The protein kinesin family member 26B (KIF26B) is aberrantly expressed in various cancers. However, its particular role and association with tumor immune infiltration in colon adenocarcinoma (COAD) remain unclear.

METHODS

All original data were downloaded directly from The Cancer Genome Atlas (TCGA), UCSC Xena, and Gene Expression Omnibus (GEO) databases and processed with R 3.6.3. KIF26B expression was analyzed using Oncomine, TIMER, TCGA, GEO databases, and our clinical specimens. KIF26B expression at the protein level was explored with Human Protein Atlas (HPA) database. The upstream miRNAs and lncRNAs were predicted by StarBase and validated using RT-qPCR. Correlation of KIF26B expression with the expression of immune-related or immune checkpoint genes and GSEA analysis of KIF26B-related genes were investigated via R software. Relationship of KIF26B expression with immune biomarkers or tumor immune infiltration levels was studied through GEPIA2 and TIMER databases.

RESULTS

KIF26B was upregulated, and its overexpression was closely related to overall survival (OS), disease-specific survival (DSS), progression-free interval (PFI), T stage, N stage, and CEA levels in COAD. MIR4435-2HG/hsa-miR-500a-3p/KIF26B axis was identified as the promising regulatory pathway of KIF26B. KIF26B expression was positively correlated with immune-related genes, tumor immune infiltration, and biomarker genes of immune cells in COAD, and KIF26B-related genes were significantly enriched in macrophage activation-related pathways. Expression of immune checkpoint genes, including PDCD1, CD274, and CTLA4, was also closely related to KIF26B expression.

CONCLUSIONS

Our results clarified that ncRNA-based increased KIF26B expression was associated with a worse prognosis and high tumor immune infiltration in COAD.

KIF26B Is Overexpressed in Medulloblastoma and Promotes Malignant Progression by Activating the PI3K/AKT Pathway

Medulloblastoma is one of the most common malignant tumors of the central nervous system in children. Although KIF2B was reported as an oncogene in several malignant tumor types, its role in medulloblastoma has not been studied so far. The PCR results of our study showed that KIF26B is highly expressed in medulloblastoma, and its high expression is associated with a high clinical stage. Knockdown the expression of KIF26B could significantly impair the proliferation and migration of medulloblastoma cells. KIF26B promotes the malignant progression of medulloblastoma by affecting the expression of phosphorylation of key proteins in the PI3K/AKT signaling pathway. With the help of 740 Y-P, activating the pi3k signaling pathway can partially rescue the phenotype. Therefore, our experimental results suggest that KIF26B is a potential target for medulloblastoma.

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.

Targeting kinesin family member 21B by miR-132-3p represses cell proliferation, migration and invasion in gastric cancer

Recently, kinesin family member 21B (KIF21B) has been reported to be an oncogene in non-small cell lung cancer and hepatocellular carcinoma. However, the functional role of KIF21B and related molecular mechanisms in gastric cancer (GC) remain largely uncovered. In this study, online bioinformatics analysis showed that KIF21B was overexpression in GC and predicted poor prognosis. Consistently, we found that the protein expression of KIF21B was upregulated in GC tissues compared with adjacent tissues by immunohistochemistry. Knockdown of KIF21B significantly suppressed cell proliferation, migration and invasion in GC cell lines (AGS and SNU-5) using Cell counting kit‑8 (CCK-8) assay, colony formation and transwell assay. KIF21B was confirmed as the target of miR-132-3p in GC cells by luciferase reporter assay. Moreover, miR-132-3p was down-regulated and KIF21B expression was upregulated in GC tissues. Overexpression of KIF21B reversed the miR-132-3p-mediated suppressive effects on GC cell proliferation, migration and invasion. Furthermore, miR-132-3p overexpression downregulated the protein levels of Wnt1, c-Myc, β-catenin, proliferating cell nuclear antigen (PCNA) and N-cadherin, and upregulated E-cadherin expression in GC cells, which were all alleviated after KIF21B overexpression. In conclusion, our findings indicate that down-regulation of KIF21B by miR-132-3p suppresses cellular functions in GC, which might be linked to reduced Wnt/β-catenin signaling.

KIF26B in the Prognosis and Immune Biomarking of Various Cancers: A Pan-Cancer Study

KIF26B has been identified as an oncogene in several tumors; however, its utility as a prognostic indicator for various cancers has not yet been comprehensively evaluated. Here, we first examined how KIF26B intervenes in thirty-three cancers within the TCGA database, including potential immunological functions, and how it affects the prognosis. Based on the open databases TCGA, TIMER2, GEPIA2, GTEx, CPTAC, and HPA, we found that, when compared with normal tissues, KIF26B is overexpressed in 22 tumor tissues. Following a survival analysis, a relationship between the expression of KIF26B and the prognosis of various cancers was observed. Among the genetic alterations assessed, mutations were the most frequent. On the contrary, high phosphorylation levels of S977 were detected in breast cancer, KIRC, LUAD, and UCEC. We also found positive or negative correlations between KIF26B and the immune infiltration of endothelial cells and cancer-associated fibroblast infiltration. This could imply that patients may benefit from immunotherapy. Finally, KEGG pathways and GO enrichment analyses were implemented to identify the molecular mechanisms of KIF26B. This study illustrates the function of KIF26B from a pan-cancer perspective and offers a new horizon for cancer prognostic and immunotherapeutic investigations.

Establishment and validation of a novel invasion-related gene signature for predicting the prognosis of ovarian cancer

BACKGROUND

Ovarian cancer (OC) is an invasive gynaecologic cancer with a high cancer-related death rate. The purpose of this study was to establish an invasion-related multigene signature to predict the prognostic risk of OC.

METHODS

We extracted 97 invasion-related genes from The Cancer Genome Atlas (TCGA) database. Then, the ConsensusClusterPlus and limma packages were used to calculate differentially expressed genes (DEGs). To calculate the immune scores of the molecular subtypes, we used ESTIMATE to evaluate the stromal score, immune score and ESTIMATE score. MCP-counter and the GSVA package ssgsea were used to evaluate the types of infiltrating immune cells. Survival and nomogram analyses were performed to explore the prognostic value of the signature. Finally, qPCR, immunohistochemistry staining and functional assays were used to evaluate the expression and biological abilities of the signature genes in OC.

RESULTS

Based on the consistent clustering of invasion-related genes, cases in the OC datasets were divided into two subtypes. A significant difference was observed in prognosis between the two subtypes. Most genes were highly expressed in the C1 group. Based on the C1 group genes, we constructed an invasion-related 6-gene prognostic risk model. Furthermore, to verify the signature, we used the TCGA-test and GSE32062 and GSE17260 chip datasets for testing and finally obtained a good risk prediction effect in those datasets. Moreover, the results of the qPCR and immunohistochemistry staining assays revealed that KIF26B, VSIG4 and COL6A6 were upregulated and that FOXJ1, MXRA5 and CXCL9 were downregulated in OC tissues. The functional study showed that the expression of KIF26B, VSIG4, COL6A6, FOXJ1, MXRA5 and CXCL9 can regulate the migration and invasion abilities of OC cells.

CONCLUSION

We developed a 6-gene prognostic stratification system (FOXJ1, MXRA5, KIF26B, VSIG4, CXCL9 and COL6A6) that is independent of clinical features. These results suggest that the signature could potentially be used to evaluate the prognostic risk of OC patients.

Fusobacterium nucleatum reduces METTL3-mediated m6A modification and contributes to colorectal cancer metastasis

Microbiota-host interactions play critical roles in colorectal cancer (CRC) progression, however, the underlying mechanisms remain elusive. Here, we uncover that Fusobacterium nucleatum (F. nucleatum) induces a dramatic decline of m⁶A modifications in CRC cells and patient-derived xenograft (PDX) tissues by downregulation of an m⁶A methyltransferase METTL3, contributing to inducation of CRC aggressiveness. Mechanistically, we characterized forkhead box D3 (FOXD3) as a transcription factor for METTL3. F. nucleatum activates YAP signaling, inhibits FOXD3 expression, and subsequently reduces METTL3 transcription. Downregulation of METTL3 promotes its target kinesin family member 26B (KIF26B) expression by reducing its m⁶A levels and diminishing YTHDF2-dependent mRNA degradation, which contributes to F. nucleatum-induced CRC metastasis. Moreover, METTL3 expression is negatively correlated with F. nucleatum and KIF26B levels in CRC tissues. A high expression of KIF26B is also significantly correlated with a shorter survival time of CRC patients. Together, our findings provide insights into modulating human m⁶A epitranscriptome by gut microbiota, and its significance in CRC progression.

ELK1-induced up-regulation of KIF26B promotes cell cycle progression in breast cancer

KIF26B is a member of the kinesin superfamily that is up-regulated in various tumors, including breast cancer (BC), which can promote tumor progression. This study aimed to investigate the potential function of KIF26B in BC, and the underlying mechanisms, focusing mainly on cell proliferation. KIF26B expression was examined in BC tissue samples obtained from 99 patients. Then, we performed MTS, EdU and flow cytometry assays to detect cell proliferation, and western blotting to measure the expression of cell cycle-related proteins in MDA-MB-231 and MDA-MB-468 cells following KIF26B knockdown. Promoter analysis was used to study the upstream regulatory mechanism of KIF26B. KIF26B was upregulated in BC tissues. High expression of KIF26B was associated with clinicopathological parameters, such as positive lymph node metastasis, higher tumor grade, and higher proliferative index in BC. Furthermore, knockdown of KIF26B expression inhibited MDA-MB-231 and MDA-MB-468 cell proliferation, arresting cells in the G₁ phase of the cell cycle in vitro. Similarly, KIF26B silencing decreased the expression levels of Wnt, β-catenin, and cell cycle-related proteins such as c-Myc, cyclin D1, and cyclin-dependent kinase 4, while increasing the expression of p27. Moreover, ELK1 could bind to the core promoter region of KIF26B and activate its transcription. KIF26B acts as an oncogene in BC by regulating multiple proteins involved in the cell cycle. ELK1 activates KIF26B transcription.

Association of a Novel KIF26B Gene Polymorphism with Susceptibility to Schizophrenia and Breast Cancer: A Case-Control Study

Background

KIF26B gene is found to play essential roles in regulating different aspects of cell proliferation and development of the nervous system. We aimed to determine if rs12407427 T/C polymorphism could affect susceptibility to schizophrenia (SZN) and breast cancer (BC), the two genetically correlated diseases.

Methods

The current case-control study was performed from Aug 2018 to Dec 2018. Briefly, 159 female pathologically confirmed BC cases referring to Alzahra Hospital, Isfahan, Iran, and 102 psychologically confirmed SZN patients (60 males and 42 females) admitted to Baharan Hospital, Zahedan, Iran, were enrolled. Using the salting-out method, genomic DNA was extracted, and variants were genotyped using allele-specific amplification refractory mutation system polymerase chain reaction (ARMS-PCR) method.

Results

The results revealed a significant association between the KIF26B rs12407427 codominant CT (P=0.001), CC (P=0.0001), dominant CT+CC, and recessive CC (P=0.001) genotypes with the risk of developing SZN. Significant correlations were also found regarding rs12407427 and BC susceptibility in different inheritance models, including over-dominant CT (P=0.026), dominant CT+CC (P=0.001), recessive CC (P=0.009), and codominant CT and CC (P=0.001) genotypes. The over-presence of the C allele was also correlated with an increased risk for SZN (P=0.0001) and BC (P=0.0001). Finally, computational analysis predicted that T/C variation in this polymorphism could change the binding sites in proteins involved in splicing.

Conclusion

rs12407427 T/C as a de novo KIF26B variant might be a novel genetic biomarker for SZN and/or BC susceptibility in a sample of the Iranian population.

Kinesin superfamily protein 21B acts as an oncogene in non-small cell lung cancer

Background

Kinesin superfamily proteins (KIFs) serve as microtubule-dependent molecular motors, and are involved in the progression of many malignant tumors. In this study, we aimed to investigate the expression pattern and precise role of kinesin family member 21B (KIF21B) in non-small cell lung cancer (NSCLC).

Methods

KIF21B expression in 72 cases of NSCLC tissues was measured by immunohistochemical staining (IHC). We used shRNA-KIF21B interference to silence KIF21B in NSCLC H1299 and A549 cells and normal lung epithelial bronchus BEAS-2B cells. The biological roles of KIF21B in the growth and metastasis abilities of NSCLC cells were measured by Cell Counting Kit-8 (CCK8), colony formation and Hoechst 33342/PI, wound-healing, and Transwell assays, respectively. Expression of apoptosis-related proteins was determined using western blot. The effect of KIF21B on tumor growth in vivo was examined using nude mice model.

Results

KIF21B was up-regulated in NSCLC tissues, and correlated with pathological lymph node and pTNM stage, its high expression was predicted a poor prognosis of patients with NSCLC. Silencing of KIF21B mediated by lentivirus-delivered shRNA significantly inhibited the proliferation ability of H1299 and A549 cells. KIF21B knockdown increased apoptosis in H1299 and A549 cells, down-regulated the expression of Bcl-2 and up-regulated the expression of Bax and active Caspase 3. Moreover, KIF21B knockdown decreased the level of phosphorylated form of Akt (p-Akt) and Cyclin D1 expression in H1299 and A549 cells. In addition, silencing of KIF21B impeded the migration and invasion of H1299 and A549 cells. Further, silencing of KIF 21B dramatically inhibited xenograft growth in BALB/c nude mice. However, silencing of KIF21B did not affect the proliferation, migration and invasion of BEAS-2B cells.

Conclusions

These results reveal that KIF21B is up-regulated in NSCLC and acts as an oncogene in the growth and metastasis of NSCLC, which may function as a potential therapeutic target and a prognostic biomarker for NSCLC.

Knockdown of A-kinase anchor protein 4 inhibits proliferation of triple-negative breast cancer cells in vitro and in vivo

Triple-negative breast cancers are the most aggressive subtypes with poor prognosis due to lack of targeted cancer therapy. Recently, we reported an association of A-kinase anchor protein 4 expression with various clinico-pathological parameters of breast cancer patients. In this context, we examined the effect of knockdown of A-kinase anchor protein 4 on cell cycle, apoptosis, cellular proliferation, colony formation, migration, and invasion in triple-negative breast cancer cells. We also examined the synergistic cytotoxic effect of paclitaxel on A-kinase anchor protein 4 downregulated triple-negative breast cancer cells. Knockdown of A-kinase anchor protein 4 resulted in significant reduction in cellular growth and migratory abilities. Interestingly, we also observed enhanced cell death in A-kinase anchor protein 4 downregulated cells treated with paclitaxel. Knockdown of A-kinase anchor protein 4 in cell cycle resulted in G0/G1 phase arrest. Knockdown of A-kinase anchor protein 4 also led to increased reactive oxygen species generation as a result of upregulation of NOXA and CHOP. In addition, levels of cyclins, cyclin-dependent kinases, anti-apoptotic molecules, and mesenchymal markers were reduced in A-kinase anchor protein 4 downregulated cells. Moreover, downregulation of A-kinase anchor protein 4 also caused tumor growth reduction in in vivo studies. These data together suggest that A-kinase anchor protein 4 downregulation inhibits various malignant properties and enhances the cytotoxic effect of paclitaxel, and this combinatorial approach could be useful for triple-negative breast cancer treatment.

KIF18B as a regulator in microtubule movement accelerates tumor progression and triggers poor outcome in lung adenocarcinoma

KIF18B is involved in several tumor progression and exerts critical effects on microtubule growth during mitosis, but its role in lung adenocarcinoma still remains rare. Hence, we attempted to explore the biological function of KIF18B in lung adenocarcinoma. We first analyzed the expressional pattern of KIF18B in lung adenocarcinoma, and detected the correlation between KIF18B expression and clinical characteristics in lung adenocarcinoma based on The Cancer Genome Atlas (TCGA) database and Oncomine dataset. Subsequently, cell counting kit-8 (CCK-8) assay, wound-healing analysis, and transwell method were performed to assess the effects of KIF18B in lung adenocarcinoma cells. Quantitative real-time reverse transcription-PCR (qRT-PCR) and western blotting were utilized to measure the mRNA and protein expression levels. Our results illustrated that KIF18B expression was significantly up-regulated in lung adenocarcinoma samples compared to normal specimens. High levels of KIF18B were associated with unfavorable prognosis of lung adenocarcinoma patients. Down-regulation of KIF18B in lung adenocarcinoma cells inhibited cell prolifartion, migration, and invasion. Western blot assay demonstrated that KIF18B knockdown markedly decreased Rac1-GTP expression, an important marker of migration and invasion in tumors. Moreover, the phosphorylation of AKT and mTOR expression levels were attenuated after KIF18B knockdown. Taken together, these data enhanced the point that KIF18B might promote lung adenocarcinoma cell proliferation, migration, and invasion by activating Rac1 and mediating the AKT/mTOR signaling pathway.

miR-450b-5p loss mediated KIF26B activation promoted hepatocellular carcinoma progression by activating PI3K/AKT pathway

Background

Kinesin family member 26B (KIF26B) is unveiled acted as important role in many solid tumors, however, the function of KIF26B in hepatocellular carcinoma (HCC) is unclear.

Methods

The expression of KIF26B in HCC tissues and cell lines were measured with immunochemistry, real-time PCR and western blotting. The correlation between KIF26B expression and clinicopathological characteristics were analyzed by SPSS19.0. Functional experiments of KIF26B was conducted by CCK-8, transwell, EDU, colony formation in vitro and tumorigenesis in vivo. The gene set enrichment analysis was used to search the downstream pathway, luciferase reporter experiment was used to find the upstream regulatory factor of KIF26B.

Results

In this study, we found that KIF26B was overexpressed both in HCC tissues and cell lines. High expression of KIF26B was associated with poor overall survival (OS), late TNM stage and poor differentiation. Loss of function experiments showed that suppression of KIF26B could inhibit cell viability, proliferation rate and invasion ability of HCC cells. KEGG and GO analysis showed that expression of KIF26B was highly relevant with PI3K/AKT signal pathway, and suppression of KIF26B could decrease the expression of m-TOR, p-PI3K and p-AKT. Further study demonstrated that expression of KIF26B was negative correlated with miR-450b-5p level in HCC tissues, and miR-450b-5p could inhibit cell viability, proliferation rate and invasion ability of HCC cells via targeted inhibiting KIF26B.

Conclusion

Our study demonstrated that miR-450-5p/KIF26B/AKT axis is critical for progression of HCC, and might provide novel prognostic biomarker and therapeutic target for HCC.

Electronic supplementary material

The online version of this article (10.1186/s12935-019-0923-x) contains supplementary material, which is available to authorized users.

Golgi Membrane Protein 1 (GOLM1) Promotes Growth and Metastasis of Breast Cancer Cells via Regulating Matrix Metalloproteinase-13 (MMP13)

Background

Breast cancer (BC) is the leading cause of death in women worldwide. Golgi membrane protein 1 (GOLM1) has been identified as novel regulator in carcinogenesis, but its function in BC is unclear.

Material/Methods

The expression of GOLM1 in BC tissues and cell lines was detected by using qRT-PCR assay. CCK-8 and colony-formation assays were used to evaluate BC cell growth in vivo. Wound-healing and Transwell assays were used to detect cell migration and invasion. To investigate GOLM1 functions in vivo, we established a xenograft mice model and a lung metastasis model. The level of epithelial-to-mesenchymal transition (EMT)-related markers was analyzed by immunofluorescent staining.

Result

GOLM1 was overexpressed in BC cell lines and tissues. Overexpression of GOLM1 induced EMT and promoted proliferation, migration, and invasion of BC cells. Furthermore, overexpressing of GOLM1 markedly promoted the tumorigenicity and metastasis of BC cells in vivo, whereas knock-down of GOLM1 caused the opposite outcomes. Furthermore, we proved that GOLM1 promoted BC cell aggressiveness by regulating matrix metalloproteinase-13 (MMP13).

Conclusions

Our results prove that GOLM1 facilitates the growth and metastasis of breast cancer cells.

miRNA-101-5p inhibits the growth and aggressiveness of NSCLC cells through targeting CXCL6

Background

The purpose of this study is to explore the potential biological roles of miR-101-5p in the progression of non-small-cell lung carcinoma (NSCLC).

Methods

The levels of miR-101-5p and chemokine (C-X-C motif) ligand 6 (CXCL6) in NSCLC tissues and cells were detected using the quantitative real-time PCR (qRT-PCR) assay. Proliferation, colony formation, migration and invasion assays were conducted using miR-101-5p-transfected NSCLC cells in vitro. The expression of CXCL6 was measured using immunofluorescence assay. Xenograft model and lung metastasis model were constructed to further reveal the precise roles of miR-101-5p in the lung metastasis and growth of NSCLC cells in vivo.

Results

miR-101-5p was underregulated in NSCLC tissues when compared with that in the normal controls. The levels of miR-101-5p were lower in NSCLC cells (H1975, A549, HCC827 and H1650) than in non-tumorigenic human bronchial epithelial cells (BEAS-2B). Overregulation of miR-101-5p restrained the aggressiveness phenotypes of NSCLC cells in vitro. Furthermore, overregulation of miR-101-5p reduced the tumor growth and pulmonary metastasis of NSCLC cells in vivo. CXCL6 was the target gene of miR-101-5p in NSCLC. The mRNA levels of CXCL6 were negatively associated with the levels of miR-101-5p in NSCLC tissues. Finally, the rescue experiments suggested that the inhibitory role of miR-101-5p was mediated by regulating the expression of CXCL6 in NSCLC.

Conclusion

These findings indicated that overregulation of miR-101-5p restrained the progression of NSCLC cells by targeting CXCL6 and might function as a potential therapeutic target for NSCLC.

MicroRNA-645 targets urokinase plasminogen activator and decreases the invasive growth of MDA-MB-231 triple-negative breast cancer cells

Background

Urokinase plasminogen activator (uPA) promotes the in vivo invasive growth of HCC cells by cleaving and activating matrix metalloproteinases (MMPs) to induce the destruction of the extracellular matrix of triple-negative breast cancer (TNBC) cells. The identification of microRNAs that target uPA and decrease uPA expression would be useful for attenuating the in vivo invasive growth of TNBC cells.

Materials and methods

MicroRNA-645 (miR-645) was identified using an online tool (miRDB) as potentially targeting uPA; miR-645 inhibition of uPA was confirmed by western blot experiments. The effects of miR-645 on the in vivo invasive growth of TNBC cells were examined using an intrahepatic tumor model in nude mice, and the miR-645 mechanism of action was explored with MMP cleaving experiments.

Results

Through virtual screening, we discovered that miR-645 potentially targeted the uPA 3′ untranslated region. This targeting was confirmed by western blot experiments and miR-645 lentiviral particle (LV-645) transduction that inhibited uPA expression in MDA-MB-231 TNBC cells. The LV-645 inhibition of uPA led to the decreased invasive growth of TNBC cells in nude mice. The mechanism data indicated that the uPA inhibition resulted in a decreased cleaving of the pro-MMP-9 protein.

Conclusion

Targeting uPA with miR-645 decreased the in vivo invasive growth of TNBC cells. These results suggest that miR-645 may represent a promising treatment strategy for TNBC.

KIF26B promotes cell proliferation and migration through the FGF2/ERK signaling pathway in breast cancer

BACKGROUND

Many studies have suggested that high KIF26B expression is directly linked to poor prognostic outcomes in breast cancer. However, the exact role of KIF26B in breast cancer progression is not fully understood. In this study, we aimed to explore the function and mechanism of KIF26B in breast cancer progression.

METHODS

Quantitative real-time PCR and immunohistochemistry analysis were used to detect KIF26B expression in breast cancer cell lines and patient samples. Cell proliferation was assessed by CCK-8 assay, and cell migration and invasion were evaluated by wound healing assay and transwell assay. Western blot analysis was carried out to assess the underlying molecular mechanisms. Tumor formation and metastasis were determined by in vivo mouse experiments.

RESULTS

KIF26B levels were significantly increased in breast cancer cells and patient samples. KIF26B level correlated with tumor size, TNM grade, and differentiation in patients with breast cancer. Overexpressing KIF26B in vitro promoted breast cancer cell proliferation and migration by activating FGF2/ERK signaling, while silencing KIF26B had the opposite effects. Similarly, KIF26B knockdown repressed tumor formation and metastasis in nude mice.

CONCLUSION

KIF26B promoted the development and progression of breast cancer and might act as a potential therapeutic target for treating breast cancer.