Breast cancer cell invasion mediated by Gα12 signaling involves expression of interleukins-6 and -8, and matrix metalloproteinase-2

7-Geranyloxycoumarin modulated metastatic potential of osteosarcoma cells via interaction with MMPs and JAK1/2

Osteosarcoma (OS) is a highly aggressive bone cancer that primarily affects young adults. The tumor microenvironment and molecular mediators, including Janus kinases (JAKs) and matrix metalloproteinases (MMPs), significantly influence OS metastasis; activation of the JAK/STAT pathway enhances MMP expression and activity, promoting OS metastasis. 7-Geranyloxycoumarin, a natural agent found in various edible fruits and vegetables, possesses valuable pharmaceutical activities. This study aimed to investigate the effects of 7-geranyloxycoumarin on the metastasis of OS cells for the first time. To achieve this, a protein-protein interaction (PPI) network was constructed from the potential molecular and pathogenic targets associated with 7-geranyloxycoumarin and OS to identify overlapping targets. Subsequently, GO and KEGG pathway enrichment analyses were conducted. Molecular docking and dynamic simulations were also performed to elucidate the binding affinity of 7-geranyloxycoumarin with JAK1 and JAK2. For in vitro studies, 7-geranyloxycoumarin was first extracted from Ferula szowitsiana using thin-layer chromatography. The cells were then treated and evaluated for viability, apoptosis, migration, invasion, adhesion, and MMPs activity. The study identified 50 shared targets and revealed MMP-2, MMP-9, JAK1, and JAK2 as hub genes, confirmed through enrichment analyses. Molecular docking revealed strong interactions between 7-geranyloxycoumarin and JAK1 and JAK2 proteins, and molecular dynamics simulations indicated both conformational flexibility and binding stability of the ligand-protein complex. Moreover, experimental studies demonstrated that 7-geranyloxycoumarin did not induce apoptosis but significantly altered the migration, invasion, and adhesion of OS cells by inhibiting the activity of MMPs. In conclusion, 7-geranyloxycoumarin is proposed as a promising therapeutic agent for targeting metastasis in OS cells.

Cross-talk between non-ionizing electromagnetic fields and metastasis; EMT and hybrid E/M may explain the anticancer role of EMFs

Recent studies have shown that non-ionizing electromagnetic fields (NIEMFs) in a specific frequency, intensity, and exposure time can have anti-cancer effects on various cancer cells; however, the underlying precise mechanism of action is not transparent. Most cancer deaths are due to metastasis. This important phenomenon plays an inevitable role in different steps of cancer including progression and development. It has different stages including invasion, intravasation, migration, extravasation, and homing. Epithelial-mesenchymal transition (EMT), as well as hybrid E/M state, are biological processes, that involve both natural embryogenesis and tissue regeneration, and abnormal conditions including organ fibrosis or metastasis. In this context, some evidence reveals possible footprints of the important EMT-related pathways which may be affected in different EMFs treatments. In this article, critical EMT molecules and/or pathways which can be potentially affected by EMFs (e.g., VEGFR, ROS, P53, PI3K/AKT, MAPK, Cyclin B1, and NF-кB) are discussed to shed light on the mechanism of EMFs anti-cancer effect.

Investigating isoform switching in RHBDF2 and its role in neoplastic growth in breast cancer

Background

Breast cancer is the second leading cause of cancer-related deaths globally, and its prevalence rates are increasing daily. In the past, studies predicting therapeutic drug targets for cancer therapy focused on the assumption that one gene is responsible for producing one protein. Therefore, there is always an immense need to find promising and novel anti-cancer drug targets. Furthermore, proteases have an integral role in cell proliferation and growth because the proteolysis mechanism is an irreversible process that aids in regulating cellular growth during tumorigenesis. Therefore, an inactive rhomboid protease known as iRhom2 encoded by the gene RHBDF2 can be considered an important target for cancer treatment. Speculatively, previous studies on gene expression analysis of RHBDF2 showed heterogenous behaviour during tumorigenesis. Consistent with this, several studies have reported the antagonistic role of iRhom2 in tumorigenesis, i.e., either they are involved in negative regulation of EGFR ligands via the ERAD pathway or positively regulate EGFR ligands via the EGFR signalling pathway. Additionally, different opinions suggest iRhom2 mediated cleavage of EGFR ligands takes place TACE dependently or TACE independently. However, reconciling these seemingly opposing roles is still unclear and might be attributed to more than one transcript isoform of iRhom2.

Methods

To observe the differences at isoform resolution, the current strategy identified isoform switching in RHBDF2 via differential transcript usage using RNA-seq data during breast cancer initiation and progression. Furthermore, interacting partners were found via correlation and enriched to explain their antagonistic role.

Results

Isoform switching was observed at DCIS, grade 2 and grade 3, from canonical to the cub isoform. Neither EGFR nor ERAD was found enriched. However, pathways leading to TACE-dependent EGFR signalling pathways were more observant, specifically MAPK signalling pathways, GPCR signalling pathways, and toll-like receptor pathways. Nevertheless, it was noteworthy that during CTCs, the cub isoform switches back to the canonical isoform, and the proteasomal degradation pathway and cytoplasmic ribosomal protein pathways were significantly enriched. Therefore, it could be inferred that cub isoform functions during cancer initiation in EGFR signalling. In contrast, during metastasis, where invasion is the primary task, the isoform switches back to the canonical isoform.

RAB4A GTPase regulates epithelial-to-mesenchymal transition by modulating RAC1 activation

Epithelial-to-mesenchymal transition (EMT) is a critical underpinning process for cancer progression, recurrence and resistance to drug treatment. Identification of new regulators of EMT could lead to the development of effective therapies to improve the outcome of advanced cancers. In the current study we discovered, using a variety of in vitro and in vivo approaches, that RAB4A function is essential for EMT and related manifestation of stemness and invasive properties. Consistently, RAB4A suppression abolished the cancer cells' self-renewal and tumor forming ability. In terms of downstream signaling, we found that RAB4A regulation of EMT is achieved through its control of activation of the RAC1 GTPase. Introducing activated RAC1 efficiently rescued EMT gene expression, invasion and tumor formation suppressed by RAB4A knockdown in both the in vitro and in vivo cancer models. In summary, this study identifies a RAB4A-RAC1 signaling axis as a key regulatory mechanism for the process of EMT and cancer progression and suggests a potential therapeutic approach to controlling these processes.

Expression of MiR-335 and its target metalloproteinase genes: clinical significance in breast cancer

BACKGROUND

Early diagnosis of breast cancer decreases mortality rate; therefore, novel diagnostic methods are urgently required. In this study, authors aimed to investigate the role of serum-derived miR-335 in breast cancer, and the expression of matrix metalloproteinase-2 (MMP2) and matrix metalloproteinase-9 (MMP9) and evaluating their feasibility and clinical utility as biomarkers for the early detection of breast cancer.

MATERIALS AND METHODS

Blood samples were collected from a total of 210 individuals who were enrolled in this study. The participants were divided into newly diagnosed breast cancer patients (n = 115), patients with benign breast lesions (n =55) and healthy individuals as control group (n =40). The expression profile of miR-335, MMP2 and MMP9 were determined using quantitative polymerase chain reaction (qPCR).

RESULTS

MiR 335 expression level was down-regulated in primary breast cancer group as compared to benign breast group and healthy individuals with 98% and 94.9% sensitivity and specificity, respectively. MMP2 and MMP9 showed significantly higher expression levels in breast cancer group as compared to both benign and healthy group and reporting 92.7% and 93% sensitivity, respectively. The relations between investigated markers and pathologic types, staging, grading, and lymph node involvement were significant with these factors. Expression level of miR-335 was decreased with increased MMP2 and MMP9 at significant level.

CONCLUSION

MiR-335, MMP2, and MMP9 can be used as diagnostic markers in breast cancer.

The emerging roles of Gα12/13 proteins on the hallmarks of cancer in solid tumors

G12 proteins comprise a subfamily of G-alpha subunits of heterotrimeric GTP-binding proteins (G proteins) that link specific cell surface G protein-coupled receptors (GPCRs) to downstream signaling molecules and play important roles in human physiology. The G12 subfamily contains two family members: Gα12 and Gα13 (encoded by the GNA12 and GNA13 genes, respectively) and, as with all G proteins, their activity is regulated by their ability to bind to guanine nucleotides. Increased expression of both Gα12 and Gα13, and their enhanced signaling, has been associated with tumorigenesis and tumor progression of multiple cancer types over the past decade. Despite these strong associations, Gα12/13 proteins are underappreciated in the field of cancer. As our understanding of G protein involvement in oncogenic signaling has evolved, it has become clear that Gα12/13 signaling is pleotropic and activates specific downstream effectors in different tumor types. Further, the expression of Gα12/13 proteins is regulated through a series of transcriptional and post-transcriptional mechanisms, several of which are frequently deregulated in cancer. With the ever-increasing understanding of tumorigenic processes driven by Gα12/13 proteins, it is becoming clear that targeting Gα12/13 signaling in a context-specific manner could provide a new strategy to improve therapeutic outcomes in a number of solid tumors. In this review, we detail how Gα12/13 proteins, which were first discovered as proto-oncogenes, are now known to drive several "classical" hallmarks, and also play important roles in the "emerging" hallmarks, of cancer.

A novel anticancer chromeno-pyrimidine analogue inhibits epithelial-mesenchymal transition in lung adenocarcinoma cells

Cancer is the second most dreaded disease worldwide. It is either acquired or inherited leading to the accompanying undesirable changes in the affected cells. Most existing chemotherapeutic drugs show enormous side effects. To minimize such effects, constant progress has been observed in the field of cancer by screening the anti-cancer effects of different chemical analogues. In the current study, we investigated the mechanism of action of a novel anticancer chromeno-pyrimidine analogue. We employed MTT, LDH assay to study cytotoxicity. DNA fragmentation, fluorescence imaging, and flow cytometric techniques have been carried out to study apoptosis, ROS generation, and cell cycle respectively. Wound healing assay and western blotting were used to evaluate the markers of epithelial-mesenchymal transition associated with metastasis. Molecular docking was used to predict possible protein targets that bind to this compound. The novel analogue induced apoptosis in lung adenocarcinoma cells and exhibited anti-metastatic activity. Increased expression of E-cadherin and inhibition of epithelial-mesenchymal transition was also observed. Docking studies with metastasis-related proteins such as Frizzled-7 (CRD), and Snail1 predict a high binding affinity of CP4b to both proteins. The novel analogue is therefore an anti-metastatic compound with EMT-inhibiting property and is hypothesized to act via binding to multiple targets in cancer cells.

Comparison of Cervical Levels of Interleukins-6 and -8 in Patients with and without Cervical Intraepithelial Neoplasia

Introduction:

Interleukins-6 and -8 are two pro-inflammatory cytokines increasing in serum and local levels under malignant conditions. There are limited evidences on the association between cervical level of these two factors and cervical intraepithelial neoplasia (CIN). So, this study aimed to explore the association between cervical levels of IL-6 and IL-8 with cervical premalignant lesions.

Methods:

The present case-control study was conducted on married women undergone Pap smear for routine screening in two groups as the group with CIN (n=100) and the healthy control group (n=100). Cervical secretions were collected using sterile swab and the levels of IL-8 and IL-6 were measured by enzyme-linked immunosorbent assay (ELISA). The obtained data were analyzed by SPSS software.

Results:

The mean cervical IL-6 level was 568.66±594.62 pg/ml in the patients with CIN and 212.7±213.9 pg/ml in the controls (P <0.001). The cervical IL-8 levels in the case and control groups were measured to be 1320.43±876.5 pg/ml and 1053.59±747.64 pg/ml, respectively (p=0.02). By modifying the confounding size effect of the age and marital duration, it was determined that cervical levels of IL-6 and IL-8 were both associated with CIN.

Conclusion:

Our results showed that the cervical levels of IL-6 and IL-8 are associated with CIN independent of age and marital duration.

EcTI impairs survival and proliferation pathways in triple-negative breast cancer by modulating cell-glycosaminoglycans and inflammatory cytokines

Breast cancer is the most common malignant tumor among women worldwide, and triple-negative breast cancer is the most aggressive type of breast cancer, which does not respond to hormonal therapies. The protease inhibitor, EcTI, extracted from seeds of Enterolobium contortisiliquum, acts on the main signaling pathways of the MDA-MB-231 triple-negative breast cancer cells. This inhibitor, when bound to collagen I of the extracellular matrix, triggers a series of pathways capable of decreasing the viability, adhesion, migration, and invasion of these cells. This inhibitor can interfere in the cell cycle process through the main signaling pathways such as the adhesion, Integrin/FAK/SRC, Akt, ERK, and the cell death pathway BAX and BCL-2. It also acts by reducing the main inflammatory cytokines such as TGF-α, IL-6, IL-8, and MCP-1, besides NFκB, a transcription factor, responsible for the aggressive and metastatic characteristics of this type of tumor. Thus, the inhibitor was able to reduce the main processes of carcinogenesis of this type of cancer.

Association between matrix metalloproteinase-9 gene polymorphism and breast cancer in Brazilian women

OBJECTIVE

This study aimed to determine the relationship between rs17576 (MMP-9) polymorphism and increased cancer risk in a Brazilian breast cancer cohort.

METHODS

This study included 141 women (71 breast cancer patients and 70 controls without breast cancer) who donated 3 mL of their peripheral blood for genomic DNA extraction. This DNA was then genotyped using a real-time polymerase chain reaction.

RESULTS

The AG (rs17576) genotype was identified in 26 (18.43%) participants in the case group and in 22 (15.60%) participants in the control group (p=0.274), while the GG genotype was identified in ten (7.09%) participants in the case group and in one (0.70%) participant in the control group (p<0.003 - OR (95% CI) 13.13 (1.73, 593.08). No significant difference in the incidence rates was observed for AG or GG rs17576 genotypes in premenopausal women, p=0.813 and p=0.556, respectively. However, in postmenopausal women, the AG genotype was shown to occur in 14 (22.5%) participants in the case group and in 4 (6.45%) participants in the control (p<0.043), while GG genotype occurred in eight (12.90%) of the individuals in the case group and in none of the individuals in the control group (p<0.006).

CONCLUSION

In this study, the MMP-9 rs17576 GG polymorphic variant was shown to be significantly associated with breast cancer risk in premenopausal women, while the AG and GG genotypes were associated with increased cancer risk in postmenopausal women.

Reduced expression of microRNA-139-5p in hepatocellular carcinoma results in a poor outcome: An exploration the roles of microRNA-139-5p in tumorigenesis, advancement and prognosis at the molecular biological level using an integrated meta-analysis and bioinformatic investigation

Hepatocellular carcinoma (HCC) is generally considered one of the most common gastrointestinal malignant tumors, characterized by high invasiveness and metastatic rate, as well as insidious onset. A relationship between carcinogenicity and aberrant microRNA-139-5p (miR-139-5p) expression has been identified in multiple tumors while the specific molecular mechanisms of miR-139-5p in HCC have not yet been thoroughly elucidated. A meta-analysis of available data from The Cancer Genome Atlas (TCGA), Gene Expression Omnibus, ArrayExpress and Oncomine databases, as well as the published literature, was comprehensively conducted with the aim of examining the impact of miR-139-5p expression on HCC. Additionally, predicted downstream target genes were confirmed using a series of bioinformatics tools. Moreover, a correlative biological analysis was performed to ascertain the precise function of miR-139-5p in HCC. The results revealed that the expression of miR-139-5p was noticeably lower in HCC compared with non-tumor liver tissues according to the pooled standard mean difference, which was -0.84 [95% confidence interval (CI): -1.36 to -0.32; P<0.001]. Furthermore, associations were detected between miR-139-5p expression and certain clinicopathological characteristics of TCGA samples, including tumor grade, pathological stage and T stage. Moreover, the pooled hazard ratio (HR) for overall survival (HR=1.37; 95% CI: 1.07-1.76; P=0.001) indicated that decreased miR-139-5p expression was a risk factor for adverse outcomes. Additionally, 382 intersecting genes regulated by miR-139-5p were obtained and assembled in signaling pathways, including 'transcription factor activity, sequence-specific DNA binding', 'pathways in cancer' and 'Ras signaling pathway'. Notably, four targeted genes that were focused in 'pathways in cancer' were identified as hub genes and immunohistochemical staining of the proteins encoded by these four hub genes in liver tissues, explored using the Human Protein Atlas database, confirmed their expression patterns in HCC and normal liver tissues Findings of the present study suggest that reduced miR-139-5p expression is capable of accelerating tumor progression and is associated with a poor clinical outcome by modulating the expression of downstream target genes involved in tumor-associated signaling pathways.

GNA13 promotes tumor growth and angiogenesis by upregulating CXC chemokines via the NF-κB signaling pathway in colorectal cancer cells

GNA13 has been found overexpressed in various types of cancer, which is related to tumor metastasis and progression. However, the biological functions of GNA13 in colorectal cancer (CRC) progression remain unclear. This study aimed to explore the role of GNA13 in CRC and investigate the mechanism of how GNA13 promotes tumor growth. Interestingly, our findings showed that GNA13 is commonly upregulated in CRC, where these events are associated with a worse histologic grade and poor survival. Increased expression levels of GNA13 promoted cell growth, migration, invasion, and epithelial-mesenchymal transition, whereas GNA13 silencing abrogated these malignant phenotypes. In addition, overexpressing GNA13 in cancer cells increased the levels of the chemokines CXCL1, CXCL2, and CXCL4, which contributed to CRC proliferation and colony formation. Moreover, our mechanistic investigations suggest that the NF-κB/p65 signaling pathway was activated by the increase in GNA13 levels. Inhibiting the NF-κB/p65 pathway with an inhibitor decreased GNA13-induced migration, invasion and CXCL chemokine level increases, indicating the critical role of NF-κB/p65 signaling in mediating the effects of GNA13 in CRC. Together, these results demonstrate a key role of GNA13 overexpression in CRC that contributes to malignant behavior in cancer cells, at least in part through stimulating angiogenesis and increasing the levels of the NF-κB-dependent chemokines CXCL1, CXCL2, and CXCL4.

Silence of α1-Antitrypsin Inhibits Migration and Proliferation of Triple Negative Breast Cancer Cells

BACKGROUND α1-antitrypsin (α1-AT) is highly expressed in many tumors. However, to the best of our knowledge, its relationship to triple negative breast cancer (TNBC) has not yet been studied. Thus, in this research we first explored the influence of α1-AT silencing on the abilities of migration and invasion, and then further study its molecular mechanism in TNBC cells. MATERIAL AND METHODS The viability of MDA-MB-231 cells were detected using cell counting kit-8 (CCK-8). The abilities of migration and invasion were examined by Transwell assay. The metastasis-related factors were tested respectively by quantitative real-time PCR (qRT-PCR) and western blot assays. RESULTS Our study results showed that α1-AT level in TNBC tissues was higher than non-triple negative breast cancer (n-TNBC) and adjacent normal breast tissues. The high expression of α1-AT was linked to type of cancer, tumor size, TNM stage and metastasis, but was not correlated with α1-AT expression and age. si-α1-AT suppressed the viability, migration, and invasion of cells. While si-α1-AT upregulated E-cadherin and the tissue inhibitor of metalloproteinases-2 (TIMP-2) levels, it downregulated metastasis associated 1 (MTA1), matrix metallopeptidase 2 (MMP2), phosphorylated-mammalian target of rapamycin (p-mTOR), phosphorylated-protein kinase B (p-Akt), and phosphorylated-phosphatidylinositol 3 kinase (p-PI3K) levels. We also found that the PI3K/Akt/mTOR pathway activator reversed the role of si-α1-AT in metastasis-related factors. CONCLUSIONS α1-AT was highly expressed in TNBC tissues, and its silencing suppressed the abilities of migration and invasion in TNBC cells and downregulated the PI3K/Akt/mTOR pathway. Thus, α1-AT may have a potential therapeutic effect on TNBC.

Study on the expression of p53 and MMP-2 in patients with lung cancer after interventional therapy

The aim of the study was to investigate the expression of tumor suppressor gene p53 and MMP-9 in non-small cell lung cancer (NSCLC) before and after chemotherapy, and investigate its association with the effect of chemotherapy and prognosis. Fifty-eight elderly NSCLC patients comprised the observation group. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was used to detect the expression of p53 and MMP-9 in lung cancer tissues before and after chemotherapy. Immunohistochemistry and western blot analysis were used to detect the expression of p53 and MMP-9 proteins in NSCLC tissue before and after chemotherapy. Terminal deoxynucleotidyl transferase nick end-labeling (TUNEL) was used to detect apoptotic cells. The association between the effect of chemotherapy and the expression of p53 and MMP-9 in lung cancer tissues was analysed. RT-qPCR results showed that the expression of p53 and MMP-2 mRNA in the tumor tissue after chemotherapy was significantly lower than that in the tumor tissue before chemotherapy. Western blot analysis revealed that the expression of p53 and MMP-2 protein in the tumor tissue after chemotherapy was significantly decreased. The positive expression of p53 and MMP-2 in lung cancer tissues before chemotherapy was 76.25 and 71.25%, respectively, and were reduced to 27.50 and 23.75%, respectively, after chemotherapy. After chemotherapy, the positive rates of p53 and MMP-2 were significantly lower than those before chemotherapy. TUNEL results showed that the apoptosis index increased significantly after chemotherapy. Efficiency of chemotherapy in patients with a negative expression of p53 and MMP-2 in lung cancer before chemotherapy was significantly higher than that in patients with a positive p53 and MMP-2 expression. A significant difference was found in the expression levels of p53 and MMP-2 in lung cancer before and after chemotherapy. The findings of the present study indicate that the expression levels of p53 and MMP-2 can be used as a predictor of chemotherapy sensitivity.

Expression of Th17/Treg related molecules in gastric cancer tissues

BACKGROUND/AIMS

The function of regulatory T cells (Treg) and helper T cells 17 (Th17) related indexes, such as interleukin (IL)-6, IL-17, transforming growth factor (TGF)-β1, and forkhead box protein 3(FoxP3) in gastric adenocarcinoma tissues remains undefined. We investigated and analyzed the relevance of the proteins with the clinicopathological characteristics and the interactions among them in gastric cancer.

MATERIALS AND METHODS

A total 68 gastric cancer patients and 40 healthy controls were enrolled. Immunohistochemistry (IHC) as well as quantitative real-time reverse transcription- polymerase chain reaction (RT-PCR) was used to determine the expression levels of IL-6, TGF-β1, IL-17, and FoxP3 in the prepared tissues. Statistical analysis included ANOVA and chi-square test.

RESULTS

The expression levels of IL-6, IL-17, FoxP3, and TGF-β1 had significantly increased in cancer tissues compared to controls. Clinical staging of gastric cancer were correlated with the rise of IL-6, IL-17, FoxP3, and TGF-β1 levels expressed in cancer tissues. The expression level of TGF-β1 and IL-6 was positively related to that of IL-17 and FoxP3, similar to FoxP3 and IL-17 in gastric cancer tissues.

CONCLUSION

IL-6, TGF-β1, FoxP3, and IL-17 may promote the progression of gastric cancer individually or jointly and have complex interactions.

The relationship between MMP-2 and MMP-9 expression levels with breast cancer incidence and prognosis

The relationship between the expression levels of matrix metalloproteinase-2 (MMP-2) and MMP-9 and breast cancer prognosis was studied. Two breast cancer cell lines (MDA-MB-231 and MCF-7) and one human normal breast cell line (HS578Bst) were investigated. Fluorescence real-time reverse transcription-polymerase chain reaction (RT-PCR) and western blotting were used to detect cellular mRNA and protein MMP-2 and MMP-9 expression levels. Breast cancer tissue samples from 80 patients and tumor-adjacent normal tissue samples from 40 patients were collected, and MMP-2 and MMP-9 expression in these samples were examined using immunohistochemistry (IHC). The relationship of MMP-2 and MMP-9 expression levels with breast cancer patient clinicopathological parameters and prognosis was analyzed. RT-PCR and western blot results showed that MMP-2 and MMP-9 mRNA and protein expression levels were significantly higher in MDA-MB-231 and MCF-7 cells than in HS578Bst cells. A high expression of MMP-2 and MMP-9 was found in 83.75% (67/80) and 78.75% (63/80) of breast cancer tissue samples, respectively. MMP-2 and MMP-9 expression in breast cancer tissues were significantly different from that in tumor-adjacent normal tissues (p<0.01). MMP-2 and MMP-9 expression levels in breast cancer tissues were correlated with lymph node metastasis and tumor staging. Single factor survival analysis showed that MMP-2 and MMP-9 were factors influencing breast cancer prognosis. MMP-2 and MMP-9 are highly expressed in breast cancer tissues and are closely related to lymph node metastasis and tumor staging. MMP-2 and MMP-9 can be used as reference indices for guiding breast cancer prognosis and treatment.

Extracting Intercellular Signaling Network of Cancer Tissues using Ligand-Receptor Expression Patterns from Whole-tumor and Single-cell Transcriptomes

Many behaviors of cancer, such as progression, metastasis and drug resistance etc., cannot be fully understood by genetic mutations or intracellular signaling alone. Instead, they are emergent properties of the cell community which forms a tumor. Studies of tumor heterogeneity reveal that many cancer behaviors critically depend on intercellular communication between cancer cells themselves and between cancer-stromal cells by secreted signaling molecules (ligands) and their cognate receptors. We analyzed public cancer transcriptome database for changes in cell-cell interactions as the characteristic of malignancy. We curated a list (>2,500 ligand-receptor pairs) and identified their joint enrichment in tumors from TCGA pan-cancer data. From single-cell RNA-Seq data for a case of melanoma and the specificity of the ligand-receptor interactions and their gene expression measured in individual cells, we constructed a map of a cell-cell communication network that indicates what signal is exchanged between which cell types in the tumor. Such networks establish a new formal phenotype of cancer which captures the cell-cell communication structure - it may open new opportunities for identifying molecular signatures of coordinated behaviors of cancer cells as a population - in turn may become a determinant of cancer progression potential and prognosis.

Pathomimetic avatars reveal divergent roles of microenvironment in invasive transition of ductal carcinoma in situ

BACKGROUND

The breast tumor microenvironment regulates progression of ductal carcinoma in situ (DCIS) to invasive ductal carcinoma (IDC). However, it is unclear how interactions between breast epithelial and stromal cells can drive this progression and whether there are reliable microenvironmental biomarkers to predict transition of DCIS to IDC.

METHODS

We used xenograft mouse models and a 3D pathomimetic model termed mammary architecture and microenvironment engineering (MAME) to study the interplay between human breast myoepithelial cells (MEPs) and cancer-associated fibroblasts (CAFs) on DCIS progression.

RESULTS

Our results show that MEPs suppress tumor formation by DCIS cells in vivo even in the presence of CAFs. In the in vitro MAME model, MEPs reduce the size of 3D DCIS structures and their degradation of extracellular matrix. We further show that the tumor-suppressive effects of MEPs on DCIS are linked to inhibition of urokinase plasminogen activator (uPA)/urokinase plasminogen activator receptor (uPAR)-mediated proteolysis by plasminogen activator inhibitor 1 (PAI-1) and that they can lessen the tumor-promoting effects of CAFs by attenuating interleukin 6 (IL-6) signaling pathways.

CONCLUSIONS

Our studies using MAME are, to our knowledge, the first to demonstrate a divergent interplay between MEPs and CAFs within the DCIS tumor microenvironment. We show that the tumor-suppressive actions of MEPs are mediated by PAI-1, uPA and its receptor, uPAR, and are sustained even in the presence of the CAFs, which themselves enhance DCIS tumorigenesis via IL-6 signaling. Identifying tumor microenvironmental regulators of DCIS progression will be critical for defining a robust and predictive molecular signature for clinical use.

Analysis of aqueous humor concentrations of cytokines in retinoblastoma

To investigate the components of the aqueous humor (AH) in patients with retinoblastoma (RB). We collected 0.1 ml AH of 35 children with RB and 20 patients with congenital cataracts as controls. Multiplex enzyme-linked immunosorbent assays (ELISAs) and Luminex xMAP technology were used to assess 45 cytokines/chemokines, matrix metalloproteinases (MMPs), and acute-phase proteins in the identification cohort. The concentrations of IL-6, IL-7, IL-8, IFN-γ, PIGF-1, VEGF-A, β-NGF, HGF, EGF and FGF-2 were significantly higher in the AH of patients with RB than those in the control group (P<0.05). The study showed that the higher levels of IP-10, IL-6, IL-7, IL-8, IFN-γ, PIGF-1, VEGF-A, β-NGF, HGF, EGF and FGF-2 in AH may be associated with RB. Our findings may facilitate a better understanding of the molecular pathways of tumors and solid molecular targets for new strategies for therapy and the earlier diagnosis of RB.

c-Jun Contributes to Transcriptional Control of GNA12 Expression in Prostate Cancer Cells

GNA12 is the α subunit of a heterotrimeric G protein that possesses oncogenic potential. Activated GNA12 also promotes prostate and breast cancer cell invasion in vitro and in vivo, and its expression is up-regulated in many tumors, particularly metastatic tissues. In this study, we explored the control of expression of GNA12 in prostate cancer cells. Initial studies on LnCAP (low metastatic potential, containing low levels of GNA12) and PC3 (high metastatic potential, containing high GNA12 levels) cells revealed that GNA12 mRNA levels correlated with protein levels, suggesting control at the transcriptional level. To identify potential factors controlling GNA12 transcription, we cloned the upstream 5′ regulatory region of the human GNA12 gene and examined its activity using reporter assays. Deletion analysis revealed the highest level of promoter activity in a 784 bp region, and subsequent in silico analysis indicated the presence of transcription factor binding sites for C/EBP (CCAAT/enhancer binding protein), CREB1 (cAMP-response-element-binding protein 1), and c-Jun in this minimal element for transcriptional control. A small interfering RNA (siRNA) knockdown approach revealed that silencing of c-Jun expression significantly reduced GNA12 5′ regulatory region reporter activity. In addition, chromatin immunoprecipitation assays confirmed that c-Jun binds to the GNA12 5′ regulatory region in PC3 cells. Silencing of c-Jun expression reduced mRNA and protein levels of GNA12, but not the closely-related GNA13, in prostate cancer cells. Understanding the mechanisms by which GNA12 expression is controlled may aid in the development of therapies that target key elements responsible for GNA12-mediated tumor progression.

MKL1 links epigenetic activation of MMP2 to ovarian cancer cell migration and invasion

Responding to pro-metastatic cues such as low oxygen tension, cancer cells develop several different strategies to facilitate migration and invasion. During this process, expression levels of matrix metalloproteinases (MMPs) are up-regulated so that cancer cells can more easily enter or exit the circulation. In this report we show that message levels of the transcriptional modulator MKL1 were elevated in malignant forms of ovarian cancer tissues in humans when compared to more benign forms accompanying a similar change in MMP2 expression. MKL1 silencing blocked hypoxia-induced migration and invasion of ovarian cancer cells (SKOV-3) in vitro. Over-expression of MKL1 activated while MKL1 depletion repressed MMP2 transcription in SKOV-3 cells. MKL1 was recruited to the MMP2 promoter by NF-κB in response to hypoxia. Mechanistically, MKL1 recruited a histone methyltransferase, SET1, and a chromatin remodeling protein, BRG1, and coordinated their interaction to alter the chromatin structure surrounding the MMP2 promoter leading to transcriptional activation. Both BRG1 and SET1 were essential for hypoxia-induced MMP2 trans-activation. Finally, expression levels of SET1 and BRG1 were positively correlated with ovarian cancer malignancies in humans. Together, our data suggest that MKL1 promotes ovarian cancer cell migration and invasion by epigenetically activating MMP2 transcription.

Data-Driven Discovery of Extravasation Pathway in Circulating Tumor Cells

Circulating tumor cells (CTCs) play a crucial role in cancer dissemination and provide a promising source of blood-based markers. Understanding the spectrum of transcriptional profiles of CTCs and their corresponding regulatory mechanisms will allow for a more robust analysis of CTC phenotypes. The current challenge in CTC research is the acquisition of useful clinical information from the multitude of high-throughput studies. To gain a deeper understanding of CTC heterogeneity and identify genes, pathways and processes that are consistently affected across tumors, we mined the literature for gene expression profiles in CTCs. Through in silico analysis and the integration of CTC-specific genes, we found highly significant biological mechanisms and regulatory processes acting in CTCs across various cancers, with a particular enrichment of the leukocyte extravasation pathway. This pathway appears to play a pivotal role in the migration of CTCs to distant metastatic sites. We find that CTCs from multiple cancers express both epithelial and mesenchymal markers in varying amounts, which is suggestive of dynamic and hybrid states along the epithelial-mesenchymal transition (EMT) spectrum. Targeting the specific molecular nodes to monitor disease and therapeutic control of CTCs in real time will likely improve the clinical management of cancer progression and metastases.

Novel augmentation by bufalin of protein kinase C-induced cyclooxygenase-2 and IL-8 production in human breast cancer cells

Cyclooxygenase-2 (COX-2) and IL-8 are two inflammatory mediators induced by protein kinase C (PKC) via various stimuli. Both contribute significantly to cancer progression. Bufalin, a major active component of the traditional Chinese medicine Chan Su, is known to induce apoptosis in various cancer cells. This study clarifies the role and mechanism of bufalin action during PKC regulation of COX-2/IL-8 expression and investigates the associated impact on breast cancer. Using MB-231 breast cancer cells, bufalin augments PKC induction of COX-2/IL-8 at both the protein and mRNA levels, and the production of prostaglandin E2 (PGE2) and IL-8. The MAPK and NF-κB pathways are involved in both the PKC-mediated and bufalin-promoted PKC regulation of COX-2/IL-8 production. Bufalin increases PKC-induced MAPKs phosphorylation and NF-κB nuclear translocation. PGE2 stimulates the proliferation/migration of breast cancer cells. Furthermore, PKC-induced matrix metalloproteinase 3 expression is enhanced by bufalin. Bufalin significantly enhances breast cancer xenograft growth, which is accompanied by an elevation in COX-2/IL-8 expression. In conclusion, bufalin seems to promote the inflammatory response in vitro and in vivo, and this occurs, at least in part, by targeting the MAPK and NF-κB pathways, which then enhances the growth of breast cancer cells.

miR-564 acts as a dual inhibitor of PI3K and MAPK signaling networks and inhibits proliferation and invasion in breast cancer

Dysregulation of PI3K and MAPK pathways promotes uncontrolled cell proliferation, apoptotic inhibition and metastasis. Individual targeting of these pathways using kinase inhibitors has largely been insufficient due to the existence of cross-talks between these parallel cascades. MicroRNAs are small non-coding RNAs targeting several genes simultaneously and controlling cancer-related processes. To identify miRNAs repressing both PI3K and MAPK pathways in breast cancer, we re-analyzed our previous miRNA mimic screen data with reverse phase protein array (RPPA) output, and identified miR-564 inhibiting both PI3K and MAPK pathways causing markedly decreased cell proliferation through G1 arrest. Moreover, ectopic expression of miR-564 blocks epithelial-mesenchymal transition (EMT) and reduces migration and invasion of aggressive breast cancer cells. Mechanistically, miR-564 directly targets a network of genes comprising AKT2, GNA12, GYS1 and SRF, thereby facilitating simultaneous repression of PI3K and MAPK pathways. Notably, combinatorial knockdown of these target genes using a cocktail of siRNAs mimics the phenotypes exerted upon miR-564 expression. Importantly, high miR-564 expression or low expression of target genes in combination is significantly correlated with better distant relapse-free survival of patients. Overall, miR-564 is a potential dual inhibitor of PI3K and MAPK pathways, and may be an attractive target and prognostic marker for breast cancer.

Fatty acid extract from CLA-enriched egg yolks can mediate transcriptome reprogramming of MCF-7 cancer cells to prevent their growth and proliferation

Background

Our previous study showed that fatty acids extract obtained from CLA-enriched egg yolks (EFA-CLA) suppressed the viability of MCF-7 cancer cell line more effectively than extract from non-enriched egg yolks (EFA). In this study, we analysed the effect of EFA-CLA and EFA on transcriptome profile of MCF-7 cells by applying the whole Human Genome Microarray technology.

Results

We found that EFA-CLA and EFA treated cells differentially regulated genes involved in cancer development and progression. EFA-CLA, compared to EFA, positively increased the mRNA expression of TSC2 and PTEN tumor suppressors as well as decreased the expression of NOTCH1, AGPS, GNA12, STAT3, UCP2, HIGD2A, HIF1A, PPKAR1A oncogenes.

Conclusions

We show for the first time that EFA-CLA can regulate genes engaged in AKT/mTOR pathway and inhibiting cell cycle progression. The observed results are most likely achieved by the combined effect of both: incorporated CLA isomers and other fatty acids in eggs organically modified through hens’ diet. Our results suggest that CLA-enriched eggs could be easily available food products with a potential of a cancer chemopreventive agent.

Electronic supplementary material

The online version of this article (doi:10.1186/s12263-016-0537-z) contains supplementary material, which is available to authorized users.

COPD promotes migration of A549 lung cancer cells: the role of chemokine CCL21

Patients with COPD develop lung cancer more frequently than healthy smokers. At the same time, molecular mediators promoting various aspects of cancer cell progression are still elusive. In this report, we examined whether COPD can be coupled with increased migration of non-small-cell lung cancer cells A549 and, if so, whether this effect may be related to altered production and activity of chemokines CCL21, CXCL5, and CXCL12. The study showed that the migration of A549 cells through the polycarbonate membrane and basement membrane extract toward a chemotactic gradient elicited by serum from patients with COPD was markedly higher as compared with serum from healthy donors. The concentration of CCL21 and CXCL12, but not CXCL5, in serum from patients with COPD was also increased. Experiments in which CCL21- and CXCL12-dependent signaling was blocked revealed that increased migration of the cancer cells upon treatment with serum from patients with COPD was mediated exclusively by CCL21. Collectively, our results indicate that COPD may contribute to the progression of lung cancer via CCL21-dependent intensification of cancer cell migration.

Mast Cell Targeted Chimeric Toxin Can Be Developed as an Adjunctive Therapy in Colon Cancer Treatment

The association of colitis with colorectal cancer has become increasingly clear with mast cells being identified as important inflammatory cells in the process. In view of the relationship between mast cells and cancer, we studied the effect and mechanisms of mast cells in the development of colon cancer. Functional and mechanistic insights were gained from ex vivo and in vivo studies of cell interactions between mast cells and CT26 cells. Further evidence was reversely obtained in studies of mast cell targeted Fcε-PE40 chimeric toxin. Experiments revealed mast cells could induce colon tumor cell proliferation and invasion. Cancer progression was found to be related to the density of mast cells in colonic submucosa. The activation of MAPK, Rho-GTPase, and STAT pathways in colon cancer cells was triggered by mast cells during cell-to-cell interaction. Lastly, using an Fcε-PE40 chimeric toxin we constructed, we confirmed the promoting effect of mast cells in development of colon cancer. Mast cells are a promoting factor of colon cancer and thus also a potential therapeutic target. The Fcε-PE40 chimeric toxin targeting mast cells could effectively prevent colon cancer in vitro and in vivo. Consequently, these data may demonstrate a novel immunotherapeutic approach for the treatment of tumors.

Cancer development, chemoresistance, epithelial to mesenchymal transition and stem cells: A snapshot of IL-6 mediated involvement

Interleukin-6 (IL-6) is a cytokine present in tumor microenvironment. Elevated level of IL-6 is associated with cancer cell proliferation, angiogenesis and metastasis through fueling STAT3, MAPK and Akt signaling. It promotes epithelial to mesenchymal transition (EMT) through altered expression of N-cadherin, vimentin, snail, twist and E-cadherin leading to cancer metastasis. IL-6 boosts mammosphere formation, self-renewal of stem cells, stemness properties of cancer cells and recruitment of mesenchymal stem cells. IL-6 is also a contributing factor for multidrug resistance in cancer due to gp130/MAPK/STAT3 mediated activation of transcription factors C/EBPβ/δ, overexpression of p-glycoprotein, EMT transition and expansion of stem cells. The in-depth investigation of IL-6 mediated cellular effects and its signaling pathway can provide the new window for future research and clinical development of IL-6 targeted therapy in cancer. Thus, an overview is delivered in this review deciphering the emerging aspect of the predominant influence of IL-6 in malignant transformation, EMT, cancer-associated stem cells and chemoresistance.

Determinant role for the gep oncogenes, Gα12/13, in ovarian cancer cell proliferation and xenograft tumor growth

Recent studies have shown that the gip2 and gep oncogenes defined by the α-subunits of Gi2 and G12 family of G proteins, namely Gαi2 and Gα12/13, stimulate oncogenic signaling pathways in cancer cells including those derived from ovarian cancer. However, the critical α-subunit involved in ovarian cancer growth and progression in vivo remains to be identified. Using SKOV3 cells in which the expressions of individual Gα-subunits were silenced, we demonstrate that the silencing of Gα12 and Gα13 drastically attenuated serum- or lysophosphatidic acid-stimulated proliferation. In contrast, the invasive migration of these cells were reduced only by the silencing of Gαi2 or Gα13. Analyses of the xenograft tumors derived from these Gα-silenced cells indicated that only the silencing of Gα13 drastically reduced xenograft tumor growth and prolonged the survival of the mice. Similar, but albeit reduced, effect was seen with the silencing of Gα12. On the contrary, the silencing of Gαi2 or Gαq failed to exert such effect. Thus, our studies establish for the first time that Gα12/13, the putative gep oncogenes, are the determinant α-subunits involved in ovarian cancer growth in vivo and their increased oncogenicity can be correlated with its ability to stimulate both proliferation and invasive migration.