Nanoarchitecture-based photothermal ablation of cancer: A systematic review.

Photothermal therapy (PTT) is an emerging non-invasive method used in cancer treatment. In PTT, near-infrared laser light is absorbed by a chromophore and converted into heat within the tumor tissue. PTT for cancer usually combines a variety of interactive plasmonic nanomaterials with laser irradiation. PTT enjoys PT agents with high conversion efficiency to convert light into heat to destroy malignant tissue. In this review, published studies concerned with the use of nanoparticles (NPs) in PTT were collected by a systematic and comprehensive search of PubMed, Cochrane, Embase, and Scopus databases. Gold, silver and iron NPs were the most frequent choice in PTT. The use of surface modified NPs allowed selective delivery and led to a precise controlled increase in the local temperature. The presence of NPs during PTT can increase the reactive generation of oxygen species, damage the DNA and mitochondria, leading to cancer cell death mainly via apoptosis. Many studies recently used core-shell metal NPs, and the effects of the polymer coating or ligands targeted to specific cellular receptors in order to increase PTT efficiency were often reported. The effective parameters (NP type, size, concentration, coated polymers or attached ligands, exposure conditions, cell line or type, and cell death mechanisms) were investigated individually. With the advances in chemical synthesis technology, NPs with different shapes, sizes, and coatings can be prepared with desirable properties, to achieve multimodal cancer treatment with precision and specificity.

Restoration of miR-143 reduces migration and proliferation of bladder cancer cells by regulating signaling pathways involved in EMT.

MicroRNAs (miRNAs), a class of regulatory endogenous short RNAs, are involved in various biological functions by targeting the mRNA of multiple protein-coding genes and influencing their related signaling pathways. In this investigation, we upregulated microRNA-143 (miR-143) expression levels in bladder cancer (BC) EJ138 cells by pCMV-miR-143 vectors. The efficacy of transfection was verified by Flow cytometry. The influence of miR-143 overexpression on BC cells migration, proliferation, and apoptosis was detected using wound-healing assay, MTT assay, and DAPI and Annexin V/PI staining, respectively. The results demonstrated that upregulation of miR-143 in BC EJ138 cells leads to inhibited proliferation and migration. Also, restoration of miR-143 was negatively associated with the expression levels of metastatic, apoptotic, invasion, and EMT-related genes, including C-Myc, CXCR4, MDM2, Vimentin, Snail-1, and MMP-9, along with increased E-Cadherin and TP53 expression. Therefore, miR-143 may be considered a potential therapeutic target for BC.

MicroRNA-143 act as a tumor suppressor microRNA in human lung cancer cells by inhibiting cell proliferation, invasion, and migration.

BACKGROUND/AIM: MicroRNAs play crucial roles in controlling cellular biological processes. miR-143 expression is usually downregulated in different cancers. In this study, we focused on exploring the role of miR143 in NSCLC development. METHODS: Bioinformatics analyses were used to detect the expression level of miR-143 in lung tumors. The cells were transfected by pCMV-miR-143 vectors. The efficacy of transfection was verified by Flow cytometry. The influence of miR-143 replacement on NSCLC cells migration, proliferation, and apoptosis was detected using wound-healing assay, MTT assay, and DAPI staining, respectively. RESULTS: MTT assay revealed that overexpression of miR143 inhibited cell growth and proliferation. Scratch assay results demonstrated that restoration of miR143 suppressed cell migration. The qRT-PCR assay was further used to detect the assumed relationship between miR143 and apoptotic and metastatic-related genes. CONCLUSION: The findings showed that miR-143 could reduce cell proliferation, invasion, and migration by reducing CXCR4, Vimentin, MMP-1, Snail-1, C-myc expression level, and increasing E-cadherin expression levels in lung cancer cells and might be a potential target in NSCLC's targeted therapy.

Restoration of miR-330 expression suppresses lung cancer cell viability, proliferation, and migration.

Lung cancer is one of the most common cancers and its incidence is rising around the world. Various studies suggest that miR-330 acts as a tumor-suppressor microRNA (miRNA) in different types of cancers, but precisely how has remained unclear. In this study, we investigate miR-330 expression in lung cancer patient samples, as well as in vitro, by studying how normalization of miR-330 expression affects lung cancer cellular phenotypes such as viability, apoptosis, proliferation, and migration. We establish that low miR-330 expression predicts poor lung cancer prognosis. Stable restoration of reduced miR-330 expression in lung cancer cells reduces cell viability, increases the fraction of apoptotic cells, causes G2/M cell cycle arrest, and inhibits cell migration. These findings are substantiated by increased mRNA and protein expression of markers for apoptosis via the intrinsic pathway, such as caspase 9, and decreased mRNA and protein expression of markers for cell migration, such as vimentin, C-X-C chemokine receptor type 4, and matrix metalloproteinase 9. We showed that reduced miR-330 expression predicts poor lung cancer survival and that stable restoration of miR-330 expression in lung cancer cells has a broad range of tumor-suppressive effects. This indicates that miR-330 is a promising candidate for miRNA replacement therapy for lung cancer patients.

Hyaluronic acid-decorated liposomal nanoparticles for targeted delivery of 5-fluorouracil into HT-29 colorectal cancer cells.

The use of liposomes as drug carriers improves the therapeutic efficacy of anticancer drugs, while at the same time reducing side effects. Hyaluronic acid (HA) is recognized by the CD44 receptor, which is overexpressed in many cancer cells. In this study, we developed HA-modified liposomes encapsulating 5-fluorouracil (5-FU) and tested them against a CD44 expressing colorectal cell line (HT29) and a non-CD44 expressing hepatoma cell line. The average size of 5-FU-lipo and 5-FU-lipo-HA nanoparticles were 112 ± 28 and 144 ± 77 nm, respectively. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium (MTT) assay showed selective cancer cell death depending on the CD44 expression in a time-dependent manner. Apoptosis assays and cell-cycle analysis indicated that G0/G1 arrest occurred. The colony formation study revealed that cells treated with 5-FU-lipo and 5-FU-lipo-HA had reduced colony formation. Quantitative reverse-transcription polymerase chain reaction study showed that the oncogenic messenger RNA and microRNA levels were significantly reduced in the 5-FU-lipo-HA-treated group, while tumor suppressors were increased in that group. We suggest that optimal targeted delivery and release of 5-FU into colorectal cancer cells, renders them susceptible to apoptosis, cell-cycle arrest, and decreased colony formation.

The role of miR-34 in cancer drug resistance.

Resistance to conventional chemotherapy remains a major cause of cancer relapse and cancer-related deaths. Therefore, there is an urgent need to overcome resistance barriers. To improve cancer treatment approaches, it is critical to elucidate the basic mechanisms underlying drug resistance. Increasingly, the mechanisms involving micro-RNAs (miRNAs) are studied because miRNAs are also considered practical therapeutic options due to high degrees of specificity, efficacy, and accuracy, as well as their ability to target multiple genes at the same time. Years of research have firmly established miR-34 as a key tumor suppressor miRNA whose target genes are involved in drug resistance mechanisms. Indeed, numerous articles show that low levels of circulating miR-34 or tumor-specific miR-34 expression are associated with poor response to chemotherapy. In addition, elevation of inherently low miR-34 levels in resistant cancer cells effectively restores sensitivity to chemotherapeutic agents. Here, we review this literature, also highlighting some contradictory observations. In addition, we discuss the potential utility of miR-34 expression as a predictive biomarker for chemotherapeutic drug response. Although caution needs to be exercised, miR-34 is emerging as a biomarker that could improve cancer precision medicine.

miR-330 suppresses EMT and induces apoptosis by downregulating HMGA2 in human colorectal cancer.

MicroRNAs (miRNAs) are important molecular regulatorsof cellular signaling and behavior. They alter gene expression by targeting messenger RNAs, including those encoding transcriptional regulators, such as HMGA2. While HMGA2 is oncogenic in various tumors, miRNAs may be oncogenic or tumor suppressive. Here, we investigate the expression of HMGA2 and the miRNA miR-330 in a patient with colorectal cancer (CRC) samples and their effects on oncogenic cellular phenotypes. We found that HMGA2 expression is increased and miR-330 expression is decreased in CRCs and each predicts poor long-term patient survival. Stably increased miR-330 expression in human colorectal cancer cells (HCT116) and SW480 CRC cell lines downregulate the oncogenic expression of HMGA2, a predicted miR-330 target. Additionally, this promotes apoptosis and decreases cell migration and viability. Consistently, it also decreases protein-level expression of markers for epithelial-to-mesenchymal-transition (Snail-1, E-cadherin, and Vascular endothelial growth factor receptors) and transforming growth factor ß signaling (SMAD3), as well as phospho- Protein kinase B (AKT) and phospho-STAT3 levels. We conclude that miR-330 acts as a tumor suppressor miRNA in CRC by suppressing HMGA2 expression and reducing cell survival, proliferation, and migration. Thus, we identify miR-330 as a promising candidate for miRNA replacement therapy for patients with CRC.

MicroRNA-330 inhibits growth and migration of melanoma A375 cells: In vitro study.

Melanoma skin cancer is one of the main causes of male cancer-related deaths worldwide. It has been suggested that miR-330-5p can act as a tumor suppressor in various types of cancers. So, in this study, we replaced miR-330 in melanoma cancer cells by vector-based miR-330 to evaluate the effects of this microRNA on the growth and migration inhibition of melanoma cancer cells, and to determine the molecular mechanisms underlying its action. By using the MTT assay, the IC50 of Geneticin antibiotic was obtained as 460 µg/mL. The results of the qRT-PCR showed the increased expression level of miR-330 and decreased expression levels of MMP-9, CXCR4, Vimentin, melanoma cell adhesion molecule, AKT1, and E2F1 messenger RNA in A375 transfected cells. The cytotoxicity assay results demonstrated the inhibition of cancer cells proliferation. Furthermore, the wound healing test results showed a migration reduction of transfected cells with miR-330 compared with nontransfected ones. In addition, 4',6-diamidino-2-phenylindoleLB: Luria-Bertani (DAPI) staining revealed the significant nucleus fragmentation in miR-330 replaced cells, which correspond to apoptosis induction in replaced cells. The results showed that increase in miR-330 expression level could significantly inhibit the tumor cell growth and the migration of melanoma cancer cells.

Docosahexaenoic acid suppresses migration of triple-negative breast cancer cell through targeting metastasis-related genes and microRNA under normoxic and hypoxic conditions.

There is insufficient evidence with respect to the effect of the standard anticancer therapeutic agents as well as common dietary supplements on the expression of such genes and microRNAs (miRNAs). Therefore, this study was aimed to study the effect of applying linoleic acid (LA) and docosahexaenoic acid (DHA) fatty acids alone or combined with Taxol on the expression of the matrix metalloproteinase (MMP)-9, MMP-2, vimentin, and talin2 genes, tumor-suppressor miR-194 and, onco-miR-106b in triple-negative breast cancer cell line, known as MDA-MB-231. MDA-MB-231 as metastatic breast cancer cell line was cultured and treated using 0.3 µM Taxol, 100 µM DHA, and 50 µM LA for 24 hours, alone or combined with Taxol under the normoxic and hypoxic conditions. Cells were harvested, after RNA extraction and complementary DNA synthesis, analysis of the expression levels of the studied genes and miRNAs was done through the use of the quantitative real-time polymerase chain reaction (qRT-PCR). Wound healing assay and Western blot analysis were also performed for confirmation. The results of qRT-PCR showed that treating the MDA-MB-231 cells with DHA caused an increase in the miR-194 expression and a decrease in the miR-106b expression, leading to the downregulation of the MMP-2 and MMP-9, and vimentin, and upregulation of the talin2 under the normoxic and hypoxic conditions. The results of the wound healing scratch assay revealed that the administration of the DHA and the DHA-Taxol combination caused the repression of cell migration in comparison with the control groups under the normoxic and hypoxic conditions. The results of the Western blot analysis demonstrated that DHA and the DHA-Taxol combination caused an increase in the expression of the talin2 protein rather than the control cells under both normoxic and hypoxic conditions. This study showed that DHA has significant antimetastatic effects against the triple-negative breast cancer cells. DHA could serve as a promising supplementation for suppressing the breast cancer cell migration, especially under the hypoxic condition.

Effects of oral butyrate and inulin supplementation on inflammation-induced pyroptosis pathway in type 2 diabetes: A randomized, double-blind, placebo-controlled trial.

PURPOSE: Pyroptosis, a form of inflammatory programmed cell death, is activated in diabetic patients. This study was conducted to investigate the effects of daily consumption of sodium butyrate (NaBut) and high-performance (HP) inulin supplementation, individually or in combination, on the expression of pyroptosis-related genes, microRNA (miR) 146a-5p, miR-9-5p and biomarkers of oxidative stress in patients with type 2 diabetes (T2DM). METHODS: In this study, we conducted a randomized, double-blinded, placebo-controlled clinical involving sixty patients with type 2 diabetes. Participants received 600 mg/d of NaBut (group A), 10 g/d of HP inulin (group B), 600 mg/d of NaBut + 10 g/d of HP inulin (group C) or placebo (group D) for 45 consecutive days. We assessed the pyroptosis-related genes mRNA expression in peripheral blood mononuclear cells (PBMCs), as well as the plasmatic levels of miR-146a and miR-9 before and after the intervention. Moreover, blood samples of the patients at baseline and following the intervention were tested for total antioxidant capacity (TAC), superoxide dismutase (SOD) and catalase levels using enzyme-linked immunosorbent assay (ELISA). This study was registered on the Iranian Registry of Clinical Trials website (identifier: IRCT201605262017N29; https://www.irct.ir/). RESULTS: Following butyrate supplementation, the relative expression levels of TLR2/4, NF-κB1, Caspase-1, NLRP3, IL-1ß & IL-18 were significantly downregulated (p < 0.05). Furthermore, butyrate and concomitant use of butyrate and inulin caused a significant increase in the fold change of miR-146a and miR-9 compared with the placebo group (p < 0.05). Interestingly, the changes in total antioxidant capacity (p = 0.047) and superoxide dismutase (p = 0.006) were significantly increased after butyrate and concomitant use of butyrate and inulin supplement, respectively. CONCLUSION: In summary, the change in expression level of miR-146a-5p and miR-9-5p due to butyrate supplementation may have a pivotal role in alleviating of diabetes via inhibiting pyroptosis by targeting TLR2 and NF-κB1. These microRNAs might be considered as potential therapeutic targets in the treatment of type 2 diabetes but further researches is required to prove the link.

siRNA-mediated silencing of CD44 delivered by Jet Pei enhanced Doxorubicin chemo sensitivity and altered miRNA expression in human breast cancer cell line (MDA-MB468).

CD44, as a superficial cellular glycoprotein, is an essential factor in cell-cell and cell-matrix interaction. The CD44 expression level has been substantially up-regulated in breast cancer, and this upregulation facilitates tumor proliferation and angiogenesis. This study aims to evaluate the combination therapy of Jet Pei/CD44-specific-siRNA/doxorubicin in breast cancer MDA-MB468 cell line. The MTT assay, wound healing test, colony formation assay, DAPI staining, and flow cytometry were performed to investigate the tumoral cell viability, migration, clonogenesis, and apoptosis progression. The quantitative real-time PCR (qRT-PCR) was performed to demonstrate the CD44 expression level. Finally, the effect of CD44 silencing on the expression of VEGF, CXCR4, MMP9, and MiR-142-3p was measured. The combination of CD44-specific-siRNA with doxorubicin decreased tumoral metastasis, proliferation, invasion, and migration, and increased apoptosis in MDA-MB468 cells. In conclusions, CD44 can serve as a therapeutic target in breast cancer. Moreover, the combination therapy of CD44-specific-siRNA with doxorubicin can be a promising treatment for patients with breast cancer.

CD133 suppression increases the sensitivity of prostate cancer cells to paclitaxel.

One of the major barriers in cancer therapy is the resistance to conventional therapies and cancer stem cells (CSCs) are among the main causes of this problem. CD133 as a CSC marker displays stem cell-like properties, tumorigenic capacity, and drug resistance in various cancers. However, the molecular mechanism behind CD133 function in prostate cancer (PC) still remains unclear. This research aimed to illustrate the probabilistic mechanism of CD133-siRNA and paclitaxel in the reduction of chemoresistance in PC cells. To measure the cell viability, migratory capacity, CSCs properties, invasive potential, apoptosis and cell cycle progression of the cells, the MTT, wound healing, spheroid assay, colony formation assay, DAPI staining and flow cytometry assays were applied in the LNCaP cell line, respectively. Also, quantitative real-time PCR (qRT-PCR) and western blot method were used for measuring the expression of CD133 and the effects of CD133 silencing on the AKT/mTOR/c-myc axis and pro-metastatic genes expression. We showed that the CD133-siRNA considerably decreased the CD133 expression. Moreover, CD133-siRNA and paclitaxel treatment significantly decreased cell proliferation and also inhibited the ability of cell migration and invasion and reduced pro-metastatic genes expression. Additionally, we found that the simultaneous use of CD133-siRNA and paclitaxel increased the paclitaxel-induced apoptosis. Our results confirmed that CD133 silencing combined with paclitaxel synergistically could suppress cell migration, invasion, and proliferation and enhance the chemosensitivity compared with mono treatment. Therefore, CD133 silencing therapy could be viewed as a promising and efficient strategy in PC targeted therapies.

MiR-144: A New Possible Therapeutic Target and Diagnostic/Prognostic Tool in Cancers.

MicroRNAs (miRNAs) are small and non-coding RNAs that display aberrant expression in the tissue and plasma of cancer patients when tested in comparison to healthy individuals. In past decades, research data proposed that miRNAs could be diagnostic and prognostic biomarkers in cancer patients. It has been confirmed that miRNAs can act either as oncogenes by silencing tumor inhibitors or as tumor suppressors by targeting oncoproteins. MiR-144s are located in the chromosomal region 17q11.2, which is subject to significant damage in many types of cancers. In this review, we assess the involvement of miR-144s in several cancer types by illustrating the possible target genes that are related to each cancer, and we also briefly describe the clinical applications of miR-144s as a diagnostic and prognostic tool in cancers.

New emerging roles of CD133 in cancer stem cell: Signaling pathway and miRNA regulation.

Cancer stem cells (CSC) are rare immortal cells within a tumor that are able to initiate tumor progression, development, and resistance. Advances studies show that, like normal stem cells, CSCs can be both self-renewed and given rise to many cell types, therefore form tumors. A number of cell surface markers, such as CD44, CD24, and CD133 are frequently used to identify CSCs. CD133, a transmembrane glycoprotein, either alone or in collaboration with other markers, has been mainly considered to identify CSCs from different solid tumors. However, the exactness of CD133 as a cancer stem cell biomarker has not been approved yet. The clinical importance of CD133 is as a CSC marker in many cancers. Also, it contributes to shorter survival, tumor progression, and tumor recurrence. The expression of CD133 is controlled by many extracellular or intracellular factors, such as tumor microenvironment, epigenetic factors, signaling pathways, and miRNAs. In this study, it was attempted to determine: 1) CD133 function; 2) the role of CD133 in cancer; 3) CD133 regulation; 4) the therapeutic role of CD133 in cancers.

miRNA-143 replacement therapy harnesses the proliferation and migration of colorectal cancer cells in vitro.

miR-143 is a tumor suppressor miRNA which its downregulation is frequently reported in colorectal cancer (CRC). This miRNA is a negative regulator of K-RAS, c-MYC, BCL-2, and MMP-9 genes which are engaged in tumor growth and metastasis. In the present study, miR-143 restoration was performed by transfection of the pCMV-miR-143 vector into the SW-480 CRC cells. Subsequently, alterations in proliferative and migratory potential of the cells were investigated by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) and wound-healing assays, respectively. Moreover, to detect apoptosis incidence in the transfected cells, 4',6-diamidino-2-phenylindole (DAPI) staining was used. Furthermore, mRNA levels of c-MYC, K-RAS, MMP-9, and BCL-2, as potential targets of miR-143, were assessed by quantitative Real-Time PCR (qRT-PCR). Also the expression levels of c-MYC, K-RAS, and MMP-9 proteins were investigated by the western blot analysis. Finally, the ratio of BAX to BCL-2 expression, as a potential marker of the response to apoptosis stimuli, was compared between the control and test groups. Furthermore, the trypan blue test was performed to determine the cell viability in cell suspension. According to the results, a decreased viability and migratory potential was observed for the miR-143 receiving cells. The DAPI staining also confirmed the occurrence of apoptosis. Moreover, BCL-2, K-RAS, MMP-9, and c-MYC mRNAs were significantly downregulated in the miR-143 grafted cells. The BAX/BCL-2 ratio also indicated a notable increase in the cells with miR-143 overexpression. In brief, miR-143 replacement could be considered as an effective strategy for the management of CRC and attenuating its invasive features.

MicroRNAs in cancer drug resistance: Basic evidence and clinical applications.

Development of drug resistance has considerably limited the efficacy of cancer treatments, including chemotherapy and targeted therapies. Hence, understanding the molecular mechanisms underpinning the innate or the acquired resistance to these therapies is critical to improve drug efficiency and clinical outcomes. Several studies have implicated microRNAs (miRNA) in this process. MiRNAs repress gene expression by specific binding to complementary sequences in the 3' region of target messenger RNAs (mRNAs), followed by target mRNA degradation or blocked translation. By targeting molecules specific to a particular pathway within tumor cells, the new generation of cancer treatment strategies has shown significant advantages over conventional chemotherapy. However, the long-term efficacy of targeted therapies often remains poor, because tumor cells develop resistance to such therapeutics. Targeted therapies often involve monoclonal antibodies (mAbs), such as those blocking the ErB/HER tyrosine kinases, epidermal growth factor receptor (cetuximab) and HER2 (trastuzumab), and those inhibiting vascular endothelial growth factor receptor signaling (e.g., bevacizumab). Even though these are among the most used agents in tumor medicine, clinical response to these drugs is reduced due to the emergence of drug resistance as a result of toxic effects in the tumor microenvironment. Research on different types of human cancers has revealed that aberrant expression of miRNAs promotes resistance to the aforementioned drugs. In this study, we review the mechanisms of tumor cell resistance to mAb therapies and the role of miRNAs therein. Emerging treatment strategies combine therapies using innovative miRNA mimics or antagonizers with conventional approaches to maximize outcomes of patients with cancer.

Alpha7 nicotinic acetylcholine receptors in lung inflammation and carcinogenesis: Friends or foes?

The lung tissue expresses the cholinergic system including nicotinic acetylcholine receptors (nAChRs) which included in many physiologic and pathologic processes. Mounting evidence revealed that these receptors have important roles in lung carcinogenesis via modulating either stimulatory or inhibitory signaling pathways. Among different members of nicotinic receptors family, alpha7-subtype of nAChR (α7nAChR) is a critical mediator involved in both inflammatory responses and cancers. Several studies have shown that this receptor is the most powerful regulator of responses that stimulate lung cancer processes such as proliferation, angiogenesis, metastasis, and inhibition of apoptosis. Moreover, aside from its roles in the regulation of cancer pathways, there is growing evidence indicating that α7nAChR has profound impacts on lung inflammation through the cholinergic anti-inflammatory pathway. Regarding such diverse effects as well as the critical roles of nicotine as an activator of α7nAChR on lung cancer pathogenesis, its modulation has emerged as a promising target for drug developments. In this review, we aim to highlight the detrimental as well as the possible beneficial influences of α7nAChR downstream signaling cascades in the control of lung inflammation and cancer-associated properties. Consequently, by considering the significant global burden of lung cancer, delineating the complex influences of α7 receptors would be of great interest in designing novel anticancer and anti-inflammatory strategies for the patients suffering from lung cancer.

microRNAs in cancer stem cells: Biology, pathways, and therapeutic opportunities.

Cancer stem cells (CSCs) are a small subpopulation of tumor cells that have been identified in most types of cancer. Features that distinguish them from the bulk of tumor cells include their pluripotency, self-renewal capacity, low proliferation rate, and tumor-initiating ability. CSCs are highly malignant, as they confer drug resistance and facilitate tumor progression, relapse, and metastasis. The molecular mechanisms underlying CSC biology are now beginning to be understood. In this context, microRNAs (miRNAs) occupy a prominent place. These endogenous, small noncoding RNA molecules control gene expression at the posttranscriptional level. This study reviews our current understanding of how the misexpression of tumor suppressor and oncogenic miRNAs in CSCs sustain their abundance and malignant properties. We discuss how they partly do so by acting on major CSC signaling pathways, including the Wnt, Notch, Hedgehog, and BMI-1 pathways. Our current knowledge of miRNA functions in CSCs may now be used for cancer diagnostic and prognostic purposes. In addition, when combined with recent technical advances in the in vivo delivery of miRNAs, we are now in an excellent position to develop strategies that harness miRNA interference and replacement technologies for the therapeutic targeting of CSCs.

The effect of combined miR-200c replacement and cisplatin on apoptosis induction and inhibition of gastric cancer cell line migration.

One of the major obstacles in the treatment of cancer is resistance to standard chemotherapeutic drugs. According to the numerous reports, miR-200c is involved in many cancers, especially gastric cancer, and also miR-200c has been known as an effective factor in the elimination of chemotherapy resistance. The purpose of this study was to explore the potential function and mechanism of miR-200c and cisplatin in the inhibition of migration and induction of apoptosis in gastric cancer cells. In this study, first, miR-200c mimics and LNA-anti-miR-200c were transfected into KATOIII cells. Moreover, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay results revealed that increased miR-200c expression and cisplatin can more inhibited the proliferation of KATOIII cells. MiR-200c overexpression inhibited the movement of KATOIII cells in wound healing assay. Subsequently, miR-200c/cisplatin could suppress colony formation in KATOIII cells. To identify a potential miR-200c target, we investigated the effect of miR-200c modulation on RhoE, PTEN, VEGFR, and MMP9 expression levels. Increased miR-200c expression caused a reduction in VEGFR and MMP9 mRNA and protein, suggesting that VEGFR and MMP9 are targets of miR-200c. In addition, reverse-transcription polymerase chain reaction assays showed that RhoE is target gene of miR-200c and LNA-anti-miR-200c suppressed the expression of PTEN. Flow cytometry and 4',6-diamidino-2-phenylindole staining analysis indicated that miR-200c increased the cisplatin-induced apoptosis which may be associated with suppression of RhoE expression in KATOIII cells, also cell-cycle analysis showed the arrest of cell-cycle progression at the G2 phase. These data demonstrated that miR-200c functioned as a suppressor gene in KATOIII cells. Also, miR-200c can be a potential therapeutic approach to overcome chemoresistance during cisplatin chemotherapy.

miR-142-3p as tumor suppressor miRNA in the regulation of tumorigenicity, invasion and migration of human breast cancer by targeting Bach-1 expression.

BACKGROUND: Breast cancer is the most common type of cancer among women, and despite improved treatments, it remains a major challenge. However, improved mechanistic insight may lead to novel therapeutic strategies. miR-142-3p belongs to the miR-142 family and is involved in pathogenesis and metastasis of various types of malignancies by targeting several important messenger RNAs (mRNAs) including Bach-1. This is especially true for breast cancer, where Bach-1 is involved in the metastatic spread by deregulation of metastasis-associated genes. METHODS: In this study, we collected 24 breast cancer tissues with 24 adjusted normal tissues to measure the expression levels of miR-142-3p and Bach-1 mRNA using quantitative reverse-transcription polymerase chain reaction (qRT-PCR) and IHC. miR-142-3p targeting of Bach-1 expression in MCF-7 and MDA-MB-468 breast cancer cells was evaluated using bioinformatics, qRT-PCR and western blot analyses. The cellular proliferation, invasion, and migration were assessed by MTT, transwell matrigel and wound healing assay and the EMT-associated proteins C-X-C chemokine receptor type 4 (CXCR-4), matrix metalloproteinase-9 (MMP9), and vascular endothelial growth factor receptor (VEGFR) were analyzed by western blot analysis. Also, the expression levels of tumor suppressors including miR-330, miR-145, and miR-34a were estimated by qRT-PCR. RESULTS: Analysis of paired specimens of primary malignant and normal tissues showed that miR-142-3p was downregulated, while Bach-1 mRNA and protein both were overexpressed in the breast cancer tumors. This inverse relationship was confirmed by cell line experiments demonstrating that miR-142-3p expression reduced Bach-1 mRNA levels. Furthermore, replacement of miR-142-3p could inhibit the proliferation, invasion, and migration in breast cancer potentially by targeting of Bach-1 mRNA and subsequent inhibition of CXCR4, MMP9, and VEGFR protein expressions. In addition, induction of miR-142-3p could upregulate tumor suppressor miRNAs, including miR-330, miR-145, and miR34a. CONCLUSION: For the first time, our results revealed that miR-142-3p could target Bach-1in breast cancer cells leading to the reduction of EMT-related proteins and reduced cell proliferation, invasion, and migration. The results also demonstrated that miR-142-3p could regulate important tumor suppressor miRNAs in breast cancer cells. In conclusion, our results suggest that miR-142-3p could be a good candidate for the targeted therapy of breast cancer, especially for the invasive type.