Overexpressing Cancer Cells Research Articles

Aptamer-Conjugated Apigenin Nanoparticles To Target Colorectal Carcinoma: A Promising Safe Alternative of Colorectal Cancer Chemotherapy.

Apigenin has gained interest recently among researchers as a potential chemotherapeutic agent in cancer, including colorectal cancer, due to its established antiproliferative activity in vitro. Despite its impressive anticancer activity in vitro, poor water solubility and nonspecific distribution in vivo make it difficult for its emergence as a drug candidate. To overcome these problems, we formulated an aptamer-conjugated apigenin-loaded nanoparticle (apt-ANP) to target against the overexpressed colorectal cancer cell surface biomarker epithelial cell adhesion molecule (EpCAM). Aptamer conjugation was conducted on the prepared nanoparticle, characterized (by SEM, TEM, and AFM) and evaluated for its antiproliferative activity toward in vitro colon carcinoma cells and in vivo colorectal cancer model. The aptamer-conjugated nanoformulation had an average size about 226 nm, smooth surface, satisfactory drug loading 17.5 ± 1.3%, and sustained drug-release pattern. The pharmacokinetic profile as well as the biodistribution study demonstrated a maximum retention of apt-ANP in the colon as compared to free drug and aptamer-free apigenin-loaded nanoparticle (ANP). Apt-ANP enhanced therapeutic efficacy to colorectal cancer cells, whereas it minimized off-target cytotoxicity to normal cells.

The proto-oncogene Bcl3 induces immune checkpoint PD-L1 expression, mediating proliferation of ovarian cancer cells

The proto-oncogene Bcl3 induces survival and proliferation in cancer cells; however, its function and regulation in ovarian cancer (OC) remain unknown. Here, we show that Bcl3 expression is increased in human OC tissues. Surprisingly, however, we found that in addition to promoting survival, proliferation, and migration of OC cells, Bcl3 promotes both constitutive and interferon-γ (IFN)-induced expression of the immune checkpoint molecule PD-L1. The Bcl3 expression in OC cells is further increased by IFN, resulting in increased PD-L1 transcription. The mechanism consists of an IFN-induced, Bcl3- and p300-dependent PD-L1 promoter occupancy by Lys-314/315 acetylated p65 NF-κB. Blocking PD-L1 by neutralizing antibody reduces proliferation of OC cells overexpressing Bcl3, suggesting that the pro-proliferative effect of Bcl3 in OC cells is partly mediated by PD-L1. Together, this work identifies PD-L1 as a novel target of Bcl3, and links Bcl3 to IFNγ signaling and PD-L1-mediated immune escape.

Self-assembling nanoparticles biofunctionalized with magnetite-binding protein for the targeted delivery to HER2/neu overexpressing cancer cells

Surface modification of nanoparticles with various biologically active molecules makes it possible to realize the huge biomedical potential of various nanoobjects. Functionally active particles are usually obtained through stabilization by polymers and subsequent chemical conjugation with biomolecules, such as, antibodies or aptamers. This entails a number of problems, such as non-oriented conjugation, low coupling yield and the inability to easily vary the attached components on demand. To solve this problem, we developed a novel method of magnetite nanoparticles stabilization with simultaneous modification by functionally active protein – Barstar, for subsequent self-assembly of the necessary components with these particles through the interaction of high-affinity protein pair Barnase ∗ Barstar (Kaff = 1014 M−1). Namely, we developed a biocompatible Bs-C-Mms6 fusion protein containing the C-terminal part of the Mms6 (magnetite-binding protein of magnetotactic bacteria) and Barstar (an inhibitor of bacterial ribonuclease Barnase). We obtained stable in PBS magnetite nanoparticles modified with Bs-C-Mms6. These particles can be used for self-assembly with any type of Barnase-containing molecules. To demonstrate the effectiveness of this approach for the development of targeted nanoparticles, we performed a self-assembly of these particles with a fusion protein of Barnase and DARPin9.29, namely DARPin9.29-Bn. DARPin9.29 recognizes the extracellular domain of clinically important HER2/neu oncomarker. We have shown that such particles selectively bind this oncomarker and can be used to detect HER2/neu-positive cancer cells for diagnostic purposes.

Hsa_circ_0061140 Knockdown Reverses FOXM1-Mediated Cell Growth and Metastasis in Ovarian Cancer through miR-370 Sponge Activity

Circular RNAs (circRNAs) are a class of noncoding RNAs that regulate gene expression at the posttranscriptional level. The specific functions of circRNAs in ovarian cancer are yet to be established. Previous sequencing analyses have revealed an abnormal expression of hsa_circ_0061140 in ovarian cancer. The main aim of the present study is to establish the specific role of hsa_circ_0061140 in ovarian cancer. circRNA expression in ovarian cancer cells was detected via real-time qPCR. The effects on specific cellular characteristics (proliferation, migration, and the EMT) and subcellular localization of hsa_circ_0061140 were assessed via RNA fluorescence in situ hybridization, knockdown, and luciferase reporter assays in the SKOV3 and A2780 cell lines. Tumorigenesis was induced in nude mice to assess the effects of hsa_circ_0061140 on ovarian cancer growth in vivo. Our results showed that hsa_circ_0061140 was upregulated in ovarian cancer cell lines. Knockdown of hsa_circ_0061140 suppressed cell proliferation and migration, both in vivo and in vitro, by inhibiting FOXM1 expression through sponging miR-370. Overexpression of FOXM1 or suppression of miR-370 rescued hsa_circ_0061140 silencing-induced inhibition of cell proliferation, migration, and the EMT. The associations among hsa_circ_0061140, miR-370, and FOXM1 were confirmed via bioinformatic prediction and fluorescein reporter experiments. Thus, hsa_circ_0061140 appeared to function as a competing endogenous RNA of miR-370 that promoted cell growth and metastasis in ovarian cancer through regulation of the miR-370/FOXM1 pathway mediating EMT.

Cytotoxicity of Clostridium perfringens enterotoxin depends on the conditions of claudin-4 in ovarian carcinoma cells

Currently, Clostridium perfringens enterotoxin (CPE) is being investigated as an anti-cancer drug for tumors expressing the tight junction (TJ) transmembrane proteins claudin-3 and/or claudin-4. However, the optimal conditions for CPE cytotoxicity are still unclear. Our objectives were to determine the optimal conditions for CPE as an anti-cancer drug for treating ovarian cancer in vitro and in vivo. In our experiments, cells at low culture density showed higher sensitivity to CPE, suggesting that claudins at TJs were poorly accessible to CPE compared with those at the edge of cell colonies. Ovarian cancer cells cultured under calcium-depleted pretreatment conditions to disrupt TJs and to knock-down TJ proteins and E-cadherin production altered CPE cytotoxicity, which was mainly dependent on claudin-4 expression. These results suggest that the condition of claudin-4 at the cell surface is important for CPE cytotoxicity. Our in vivo experiments showed that a high dose of CPE is required for the effective treatment of peritoneal dissemination of ovarian cancer cells. Here, we suggest that the accessibility of CPE to claudins is important for its cytotoxicity and depends on the conditions of claudin-4 in vitro. In addition, E-cadherin expression in ovarian cancer cells affects the efficiency of CPE in vivo.

Hyaluronated imatinib liposomes with hybrid approach to target CD44 and P-gp overexpressing MDR cancer: an in-vitro, in-vivo and mechanistic investigation

Multi Drug Resistance (MDR) of cancer cells is a constant threat to the clinically used drugs as well as new drug development. In present work, we aimed to assess in-vitro as well as in-vivo efficacy of the developed Imatinib loaded liposomes in MDR cancer. An array of tests was also carried out to comprehensively understand the bio-mechanism that enable these nanocarriers to modulate P-gp activity. Hyaluronic acid coated, Imatinib mesylate containing lipsomes (HA-LIPO-IM) were analysed through in-vitro and in-vivo studies in MDR cancer cells and tumour models. Effect of developed hyaluronated liposomes on various biomolecular mechanisms was also evaluated. Around 3.5 times lower IC50 for HA-LIPO-IM in comparison to drug solution in HT-29 and Colo-320 cells proved the enhanced action of the drug in MDR cells. HA-LIPO formulations were demonstrated to have inhibitory effect on ATPase enzyme. Molecular masking of Imatinib mesylate and CD-44 mediated endocytosis were also found responsible for anti-MDR effect. In-vivo studies revealed the prolonged tumour accumulation and 4-fold increase in tumour regression efficacy of HA-LIPO-IM in comparison to free drug solution. The work demonstrated the target specific accumulation of HA-LIPO-IM in CD-44 overexpressing cancer cells through P-gp modulation.

Breast Cancer, Chemokines, And Metastasis: A Search for Decoy Ligands of the CXCR4 Receptor

Breast cancer (BC) is the leading cause of cancer-related deaths in young to middle-aged women worldwide. Moreover, the survival rate in BC-patients is only 20% when associated with metastatic disease. The high mortality rate observed in BC women with metastatic disease has precipitated a major challenge revealing an unmet need to develop new therapeutic strategies in treating metastatic cancer. One such approach has involved utilization of chemokines and their receptors as therapeutic targets for cancer metastasis. It has been established that a definitive correlation exists between overexpressed CXCR4 malignant cell receptors and cancer cell growth, invasion, and migration. It is also widely accepted that the CXCR4 receptor, complexed to its CXCL12 ligand, plays a major role in establishing migratory pathway gradients for cancer cells migrating to distant tissues/organ sites. It would follow that chemokine decoy ligands, such as peptide antagonists and inhibitors, could serve to induce receptor blockade and impede subsequent intracellular signaling. Such ligands, synthetic and natural, reportedly contribute to reducing cancer cell growth, invasion, adherence, and migration. The present commentary describes several existing synthetic CXCR4 receptor-ligand peptide antagonists and presents a strategy to develop naturally-occurring human protein-derived peptide candidates.

N-myc downstream-regulated gene 2 promotes proliferation of HO-8910 ovarian cancer cells

Abstract Objective To investigate N-myc downstream-regulated gene 2 (NDRG2) expression in ovarian cancer cells and its potential usefulness as a diagnostic marker and/or target for therapeutic intervention. Methods Human NDRG2L/S gene was obtained by revers-transcription polymerase chain reaction (RT-PCR). Sequence analysis confirmed the identity of NDRG2L/S gene, which was then inserted into a eukaryotic vector pLNCX2, which was in turn transfected into NDRG2 gene-negative HO-8910 cells. Flow cytometry (FCM) and 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay were conducted to determine the proliferation rate of HO-8910 cells. Cisplatin resistance of HO-8910 cells transfected with pLNCX2-NDRG2L/S was evaluated by FCM. Tumors were generated in female nude mice by subcutaneous injection of HO-8910 cells. Results NDRG2 gene was isolated and its expression vector was successfully constructed. NDRG2 expression positively correlated with the proliferation of HO-8910 cells. NDRG2L/S promoted tumorigenicity in HO-8910 cells. Conclusion The present study identified a novel function of NDRG2L/S gene and demonstrated its involvement in the promotion of ovarian cancer cell proliferation and enhancement of cisplatin resistance in HO-8910 cells. Future studies are warranted to determine the relationship between NDRG2 upregulation and ovarian cancer progression.

Lewis(y) antigen-mediated positive feedback loop induces and promotes chemotherapeutic resistance in ovarian cancer.

The present study aimed to investigate the association between Lewis(y) antigen and chemoresistance in ovarian cancer and to elucidate the underlying molecular mechanisms. Lewis(y) expression in chemoresistant ovarian cancer tissues and cells was detected by immunohistochemistry. α1,2‑fucosyltransferase (FUT1) expression in different ovarian cancer chemotherapy-resistant cells was analyzed by reverse transcription-quantitative PCR (RT-qPCR). Genes differentially expressed in the chemoresistant and sensitive groups were screened using a gene chip followed by validation using RT-qPCR and western blot analysis. We found that Lewis(y) and FUT1 expression in ovarian cancer cells was significantly increased following the induction of drug resistance. The positive expression rate and intensity of Lewis(y) in ovarian cancer chemoresistant tissues were also significantly higher than those in the sensitive group. Compared with the non-resistant cell lines, the differentially expressed genes were mainly enriched in the terms related to the transmembrane receptor protein tyrosine kinase signaling pathway and positive regulation of cell proliferation. Interaction network analysis predicted genes participating in the regulation of apoptotic processes. The highly differential expression of AnnexinA4 (ANXA4), BCL2 interacting killer(BIK), transmembrane4L six family member4(TM4SF4) and pleckstrin homology-like domain familyA member1 (PHLDA1) was validated using RT-qPCR in ovarian cancer cell lines. Finally, ANXA4 expression was increased at both the mRNA and protein level in the drug‑resistant cells, and in addition, ANXA4 contained a Lewis(y) structure. The expression of Bcl-2 and other anti-apoptotic proteins increased with the increase of Lewis(y) expression. After blocking Lewis(y) using an antibody, the expression of the involved signaling pathway and apoptosis-related proteins decreased significantly. These findings provide strong evidence that Lewis(y) is a component of the structure of the ANXA4 membrane protein. Its overexpression can abnormally activate signaling pathways and regulate the expression of a number of factors, forming a positive feedback loop to induce the chemoresistance of ovarian cancer cells, and ultimately promoting the progression of ovarian cancer.

Engineering a 3D DNA-Logic Gate Nanomachine for Bispecific Recognition and Computing on Target Cell Surfaces.

Among the vast number of recognition molecules, DNA aptamers generated from cell-SELEX exhibit unique properties for identifying cell membrane biomarkers, in particular protein receptors on cancer cells. To integrate all recognition and computing modules within a single structure, a three-dimensional (3D) DNA-based logic gate nanomachine was constructed to target overexpressed cancer cell biomarkers with bispecific recognition. Thus, when the Boolean operator "AND" returns a true value, it is followed by an "ON" signal when the specific cell type is presented. Compared with freely dispersed double-stranded DNA (dsDNA)-based molecular circuits, this 3D DNA nanostructure, termed DNA-logic gate triangular prism (TP), showed better identification performance, enabling, in turn, better molecular targeting and fabrication of recognition nanorobotics.

Uptake and light-induced cytotoxicity of hyaluronic acid-grafted liposomes containing porphyrin in tumor cells

Porphyrins are used in clinic as the photosensitizers for cancer treatment. However, most porphyrins tend to form aggregates in aqueous solution due to their hydrophobicity, which results in significantly reduced photocytotoxicities. Therefore, their applications in clinic are limited. To overcome these disadvantages, drug-carriers are designed for the delivery of porphyrins. In this study, we designed the surface modified liposomes for porphyrin delivery. Four types of porphyrins were loaded in liposome separately. We systemically investigated the porphyrin-containing liposomes in terms of their physicochemical properties as well as light-responsive properties. The hyaluronic acid derivative with aldehyde group was used to modify the liposome-porphyrin via the “click” reaction in order to enhance the uptake in CD44 overexpressed cancer cells. The results showed that 10,15,20-tetrakis(4-hydroxyphenyl) porphyrin (p-OH) had highest loading efficiency. The liposomes with p-OH showed highest toxicity to the cells with or without light exposure. The uptake of hyaluronic acid (HA) coated Lip-p-OH was proved to be specific to MDA-MB-231 cells by pretreating the cells with natural HA polymer as the block agent. This study provided an efficient strategy to enhance the cytotoxicity of porphyrin in aqueous solution, and to increase the affinity of porphyrin to the cancer cells.

Abstract 59: 14-3-3zeta overexpressing breast cancer cells promote fibroblast senescence and CAF-like phenotype

Abstract 14-3-3ζ overexpression in breast cancer is associated with accelerated cancer progression and poor clinical outcome in patients. Our previous study revealed that 14-3-3ζ overexpression promotes epithelial mesenchymal transition (EMT) of breast cancer cells, which facilitates progression of ductal carcinoma in situ (DCIS) to invasive ductal carcinoma (IDC). However, the impact of 14-3-3ζ overexpressing breast cancer cells on tumor microenvironment (TME) and the underlying mechanisms have not been explored. We found dramatically increased cancer associated fibroblast (CAF) signatures in patients' matched IDC lesions compared to their DCIS lesions, suggesting that activated fibroblasts may be involved in DCIS to IDC transition. Global gene expression profiling uncovered increased expression of pro-inflammatory cytokines/chemokines, including IL6 and IL8, in 14-3-3ζ AND ErbB2 co-overexpressed 10A.ErbB2.1433ζ cells compared to ErbB2 overexpressed 10A.ErbB2 cells. This finding was further confirmed by ELISA and validated in other breast cancer cell lines. We tested whether increased pro-inflammatory cytokines in the conditional medium (CM) from 14-3-3ζ overexpressed cancer cells promotes CAF-like phenotype. Indeed, CM from 14-3-3ζ overexpressed cancer cells significantly increased SMA+ activated fibroblast cells compared to controls. Additionally, up-regulation of β-galactosidase and reduced cell proliferation, hallmarks of senescence cells, were detected in fibroblast cells cultured in CM from 14-3-3ζ overexpressed cancer cells. Next, we explored potential mechanism of how 14-3-3ζ overexpression in cancer cells leads to up-regulation of pro-inflammatory cytokines/chemokines. Since NF-kappaB is one of the master upstream regulator of IL-6 and IL-8, we next investigated the NF-kappaB signaling activation in 14-3-3ζ overexpressed vs control cancer cells. 14-3-3ζ overexpressing cancer cells had hyperactive canonical NF-kappaB responses, including accelerated IκBα degradation, p65 phosphorylation, as well as nuclear translocation compared to 14-3-3ζ low cancer cells. Prolonged NF-kappaB signaling activation upon pro-inflammatory cytokine stimulation was also detected in 14-3-3ζ overexpressing cancer cells. These results suggest that 14-3-3ζ overexpressing cancer cells may promote fibroblast cell senescence and CAF-like phenotype by creating by a chronic inflammatory microenvironment, which ultimately enhances DCIS to IDC transition. Citation Format: Hongzhong Li, Yi Xiao, Xiangliang Yuan, Wenling Kuo, Ping Li, Dihua Yu. 14-3-3zeta overexpressing breast cancer cells promote fibroblast senescence and CAF-like phenotype [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 59.

Abstract 4490: Autocrine and paracrine effects of miR-29 in hPSCs and PDAC cells

Abstract Pancreatic ductal adenocarcinoma (PDAC) continues to be one of the most lethal malignancies worldwide and responds poorly to current therapeutic modalities. Due to its late stage diagnosis and limited response to current treatments, it is imperative to develop novel and effective therapies for PDAC. Dense fibrotic stroma associated with PDAC abrogates drug perfusion into the tumor and activated pancreatic stellate cells (PSCs) are the major stromal cells responsible for stromal reaction. Furthermore, activated PSCs are known to secrete various factors causing autocrine effects to elicit sustained PSC activation and paracrine effects on cancer cells to promote tumor progression. Our previous work has shown that loss of miR-29 is a common phenomenon of both activated PSCs and pancreatic cancer cells, and its restored expression reduces stromal accumulation and cancer growth. In addition, conditioned media from miR-29 overexpressing PSCs reduces cancer cell viability. To extend our work on the role of miR-29 in tumor-stromal interactions, we examined how autocrine and paracrine signaling is affected by miR-29 overexpression in PSCs and cancer cells. We collected the conditioned media from miR-29a overexpressing human PSCs (hPSC-CM) or cancer cells (CC-CM) and cultured nascent PSCs or cancer cells to evaluate autocrine and paracrine effects. hPSCs and PDAC cells cultured in miR-29 hPSC-CM resulted in a significant reduction of cell viability. Likewise, miR-29 overexpressing CC-CM reduced the viability of hPSCs and cancer cells. Additionally, cancer cell migration was reduced when treated with miR-29 overexpressing hPSC- and CC-CM. Taken together, our results demonstrate that conditioned media collected from miR-29 overexpressing hPSCs and cancer cells reduces hPSC/cancer cell viability and cancer cell migration. Moreover, our findings highlight the important role of miR-29 in the autocrine/paracrine interactions between PSCs and cancer cells. In our future studies, we expect to identify the key factors that are regulated by miR-29 in tumor-stromal interactions. Citation Format: Tricia Factora, Elise Briscoe, Jason Kwon, Janaiah Kota. Autocrine and paracrine effects of miR-29 in hPSCs and PDAC cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 4490.

Targeted Tubulysin B Hydrazide Conjugate for the Treatment of Luteinizing Hormone-Releasing Hormone Receptor-Positive Cancers.

The targeted delivery of chemotherapeutic agents to receptors that are overexpressed on cancer cells has become an attractive strategy to concentrate drugs in cancer cells while avoiding uptake by healthy cells. Luteinizing hormone-releasing hormone receptor (LHRH-R) has attracted considerable interest for this application, since LHRH-R is upregulated in ∼86% of prostate cancers, ∼80% of endometrial cancers, ∼80% of ovarian cancers, and ∼50% of breast cancers, but virtually absent from normal tissues. Although LHRH and related peptides have been used to deliver cytotoxic drugs to LHRH-R overexpressing cancer cells, they have suffered from off-target delivery of the therapeutic agents to the liver and kidneys. To reduce such unwanted uptake by peptide scavenger receptors in the liver and kidneys, we have explored the use of a nonpeptidic LHRH-R antagonist (NBI42902) to construct an LHRH-R targeted tubulysin conjugate (BOEPL-L3-TubBH). In vitro studies with BOEPL-L3-TubBH demonstrate that the conjugate can kill LHRH-R expressing triple-negative breast cancer cells (MDA-MB-231 cells) with low nanomolar IC50. Related studies on tumor-bearing mice further reveal that the same conjugate can eradicate MDA-MB-231 solid tumors without any measurable side-effects, yielding mice that gain weight during therapy and show no evidence of tumor recurrence for at least 5 weeks after termination of treatment. That these complete responses are LHRH-R targeted was then established by showing that identical treatment of receptor-negative (SKOV3) tumors yields no antitumor response. Overall, these data provide a proof-of-concept that LHRH-R specific targeting of an extremely toxic drug like tubulysin B can treat LHRH-R positive tumors without causing significant toxicity to healthy cells.

APOBEC3B up-regulation independently predicts ovarian cancer prognosis: a cohort study

BackgroundOvarian cancer is a heterogeneous disease with a high degree of genomic instability, pro-/antitumor immunity and inflammation, and remains the most lethal gynecologic cancer worldwide. APOBEC3B, a member of the AID/APOBEC family, is part of the innate immune system which plays a key role in combating exogenous infection especially viral infection. Studies have shown that APOBEC3B expression is elevated in a variety of cancer tissues and cell lines, and plays a prominent role in the genesis and evolution of various cancers. However, the clinical relevance of APOBEC3B in ovarian cancer needs to be further investigated. The current study aimed to evaluate the predictive value of APOBEC3B in ovarian cancer clinical outcome, and to explore possible molecular mechanisms contributing to ovarian cancer progression.MethodsThe expression of APOBEC3B in biopsy tissue specimens from 88 ovarian cancer patients was examined using immunohistochemistry. In addition, ovarian cancer cell lines were transfected with APOBEC3B siRNA or pLenti-APOBEC3B construct. Western blotting and SRB assay were performed to explore the role of APOBEC3B in ovarian cancer.ResultsPatients were followed for a median of 74.77 months following the time of surgery. Forty-two patients had died, 5 had relapsed but were still alive at the end of study, and 41 patients remained alive and had no recurrence. Over-expression of APOBEC3B was associated with advanced FIGO stage and elevated CA125 (both p< 0.05). Univariate analysis result showed that histological subtype, FIGO stage, intravascular tumor thrombus, CA125 and APOBEC3B expression were associated with overall survival and disease-free survival of ovarian cancer patients. Multivariate analysis result showed that higher APOBEC3B expression were an independent prognostic factor to predict both worse overall survival (hazard ratio: 5.18, 95% confidence interval: 1.40–11.95, p= 0.003) and disease-free survival (hazard ratio: 4.23, 95% confidence interval: 1.60–11.17, p= 0.004) of ovarian cancer patients. Furthermore, knockdown of APOBEC3B expression in ovarian cancer cells caused an decrease in cell line viability.ConclusionsAPOBEC3B expression is an independent prognostic factor in ovarian cancer patients. Knockdown of APOBEC3B expression affects ovarian cancer viability.

MiRNA‑195 suppresses cell proliferation of ovarian cancer cell by regulating VEGFR2 and AKT signaling pathways.

The present study aimed to investigate the functional effects of microRNA‑195 on ovarian cancer cells and the underling mechanism involved. Reverse transcription‑quantitative polymerase chain reaction was used to measure the expression of microRNA‑195 in patients with ovarian cancer. Cell proliferation and apoptosis were measured with MTT assay and flow cytometry, respectively. Caspase‑3/9 activity, vascular endothelial growth factor receptor (VEGFR)2 and phosphorylated protein kinase B (p‑AKT) protein expression were analyzed using caspase‑3/9 activity kits and western blot analysis. The expression of microRNA‑195 was downregulated in ovarian cancer, compared with the normal control group. Furthermore, microRNA‑195 suppresses cell proliferation and induced apoptosis of ovarian cancer cells. In addition, microRNA‑195 suppressed VEGFR2 and p‑AKT protein expression in ovarian cancer cells. The inhibition of VEGFR2 and p‑AKT increased the functional effects of microRNA‑195 on apoptosis of ovarian cancer cells. The results demonstrated that microRNA‑195 suppresses cell proliferation of ovarian cancer cells through regulation of VEGFR2 and AKT signaling pathways.

Tetrac-decorated chitosan-coated PLGA nanoparticles as a new platform for targeted delivery of SN38

New integrin-targeted nanoparticles made of chitosan-stabilized PLGA matrix was developed to specifically target colon adenocarcinoma. To this aim, SN38-encapsulated chitosan-coated PLGA NPs were conjugated with tetrac for integrin receptor-guided delivery. To provide a sustained release pattern for SN38, it was loaded into nanoparticles using single emulsion method. The size of NPs were 174.23 ± 6.12 nm with drug encapsulation efficiency and loading content of 73.16 ± 11.15 and 4.45 ± 0.31, respectively. The in vitro results confirmed that the designed nanoplatform showed specific cellular uptake and cytotoxicity in integrin overexpressing cancer cells and provided a sustained release profile for SN38. Additionally, an increased therapeutic potency of targeted formulation over both non-targeted and free drug was shown in vivo.

ADH1B promotes mesothelial clearance and ovarian cancer infiltration.

Primary debulking surgery followed by adjuvant chemotherapy is the standard treatment for ovarian cancer. Residual disease after primary surgery is associated with poor patient outcome. Previously, we discovered ADH1B to be a molecular biomarker of residual disease. In the current study, we investigated the functional role of ADH1B in promoting ovarian cancer cell invasiveness and contributing to residual disease. We discovered that ADH1B overexpression leads to a more infiltrative cancer cell phenotype, promotes metastasis, increases the adhesion of cancer cells to mesothelial cells, and increases extracellular matrix degradation. Live cell imaging revealed that ADH1B-overexpressing cancer cells efficiently cleared the mesothelial cell layer compared to control cells. Moreover, gene array analysis revealed that ADH1B affects several pathways related to the migration and invasion of cancer cells. We also discovered that hypoxia increases ADH1B expression in ovarian cancer cells. Collectively, these findings indicate that ADH1B plays an important role in the pathways that promote ovarian cancer cell infiltration and may increase the likelihood of residual disease following surgery.

Overexpression of Pyruvate Kinase Type M2 (PKM2) Promotes Ovarian Cancer Cell Growth and Survival Via Regulation of Cell Cycle Progression Related with Upregulated CCND1 and Downregulated CDKN1A Expression.

BackgroundMany findings have shown that pyruvate kinase type M2 (PKM2) plays crucial roles in regulating the occurrence and development of various human cancers; however, its roles in ovarian cancer oncogenesis remain to be determined.Material/MethodsThe expression intensity of PKM2 in ovarian cancer tissues was examined by immunohistochemistry (IHC), and was then correlated to patient clinicopathologic characteristics. The roles of PKM2 in ovarian cancer cell proliferation, growth, and survival were examined by CCK-8, colony forming, and flow cytometry assays. The potentially involved molecular were then investigated by Western blot analysis.ResultsIHC results showed that PKM2 was overexpressed in 100 of 114 (87.7%) serous ovarian cancer tissues as compared with 50 cases of non-cancerous ovarian tissues, and was associated with tumor size ≥7.5 cm and <7.5 cm (p<0.05). Overexpression of PKM2 in SKOV3 and HEY ovarian cancer cells by transfection with PKM2 lentivirus vector led to increased cell proliferation, growth, and survival, which may be related with PKM2 being able to increase cell cycle progress: G1 stage decreased, whereas S stage significantly increased. In contrast, all functions of SKOV3 and HEY cells described above were reversed by knocked down PKM2 expression using siRNA. Further data showed that overexpressed PKM2 led to increased CCND1 and decreased CDKN1A expression, whereas underexpressed PKM2 led to decreased CCND1 and increased CDKN1A expression in ovarian cancer cells.ConclusionsPKM2 may play important roles in ovarian cancer development and may be a treatment target for this cancer.

Novel Nitric Oxide Donors of Phenylsulfonylfuroxan and 3-Benzyl Coumarin Derivatives as Potent Antitumor Agents.

In this work, five new hybrids of phenylsulfonylfuroxan merging 3-benzyl coumarin and their seco-B-ring derivatives 2-6 were designed and synthesized. Among them, compound 3 showed the most potent antiproliferation activities with IC50 values range from 0.5 to 143 nM against nine drug-sensitive and four drug-resistant cancer cell lines. Preliminary pharmacologic studies showed that these compounds displayed lower toxicities than that of lead compound 1. Compound 3 obviously induced the early apoptosis and hardly affected the cell cycle of A2780, which was significantly different from compound 1. Especially, it gave 559- and 294-fold selectivity antiproliferation activity in P-gp overexpressed drug-resistant cancer cell lines MCF-7/ADR and KB-V compared to their drug-sensitive ones MCF-7 and KB, implying that compounds 2-6 might have an extra mechanism of anti-MDR-cancer with P-gp overexpression.