Intratumoral heterogeneity of ADAM23 promotes tumor growth and metastasis through LGI4 and nitric oxide signals

The construction and validation of ECM-related prognosis model in laryngeal squamous cell carcinoma

Background

Laryngeal squamous cell carcinoma (LSCC) is a kind of common and aggressive tumor with high mortality. The application of molecular biomarkers is useful for the early diagnosis and treatment of LSCC.

Methods

The expression and clinical information were obtained from The Cancer Genome Atlas (TCGA) database. Principal components analysis (PCA) was used to discriminate between LSCC and normal samples. The hub genes were screened out through univariate and multivariate cox analyses. The Kaplan-Meier (K-M) and receiver operating characteristic (ROC) curve was used to validate the predictive performance. The single sample gene set enrichment analysis (ssGSEA), Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis were used to determine the enrichment function. Protein-Protein Interaction (PPI) network was constructed in STRING. The immune analysis was performed by ESTIMATE, IPS and xCELL. The drug sensitivity was identified with GSCA database.

Results

We identified that 47 extracellular matrix (ECM) genes were differentially expressed in LSCC compared with normal group. Univariate and multivariate cox analysis determined that leucine-rich glioma-inactivated 4 (LGI4), matrilin 4 (MATN4), microfibrillar-associated protein 2 (MFAP2) and fibrinogen like 2 (FGL2) were closely related to the disease free survival (DSS) of LSCC. ROC curve determined that the risk model has a good predictive performance. PPI network showed the top 100 genes with high correlation of hub genes. The ssGSEA, GO and KEGG enrichment analyses determined that immune response was significantly involved in the development of LSCC. Immune infiltration analysis showed that most immune cells and immune checkpoints were inhibited in high risk score group. Drug sensitivity analysis showed that MATN4, FGL2 and LGI4 were negatively related to various drugs, while MFAP2 was positively related to many drugs.

Conclusion

We established a risk model constructed with four ECM-related genes, which could effectively predict the prognosis of LSCC.

2-Hydroxypropyl-β-cyclodextrin (HPβCD) as a Potential Therapeutic Agent for Breast Cancer

Cholesterol accumulation is documented in various malignancies including breast cancer. Consequently, depleting cholesterol in cancer cells can serve as a viable treatment strategy. We identified the potency of 2-hydroxypropyl-β-cyclodextrin (HPβCD), a cholesterol-depletor in vitro against two breast cancer cell lines: MCF-7 (Oestrogen-receptor positive, ER+) and MDA-MB-231 (Triple negative breast cancer (TNBC)). The results were then compared against two non-cancerous cell lines using cytotoxic-, apoptosis-, and cholesterol-based assays. Treatment with HPβCD showed preferential and significant cytotoxic potential in cancer cells, inducing apoptosis in both cancer cell lines (p < 0.001). This was mediated due to significant depletion of cholesterol (p < 0.001). We further tested HPβCD in a MF-1 mice (n = 14) xenograft model and obtained 73.9%, 94% and 100% reduction in tumour size for late-, intermediate-, and early-stage TNBC, respectively. We also detected molecular-level perturbations in the expression patterns of several genes linked to breast cancer and cholesterol signalling pathways using RT2-PCR arrays and have identified SFRP1 as a direct binding partner to HPβCD through SPR drug interaction analysis. This work unravels mechanistic insights into HPβCD-induced cholesterol depletion, which leads to intrinsic apoptosis induction. Results from this study potentiate employing cholesterol depletion as a promising unconventional anticancer therapeutic strategy, which warrants future clinical investigations.

A novel program of infiltrative control in astrocytomas: ADAM23 depletion promotes cell invasion by activating -secretase complex

Background

Infiltration is a life-threatening growth pattern in malignant astrocytomas and a significant cause of therapy resistance. It results in the tumor cell spreading deeply into the surrounding brain tissue, fostering tumor recurrence and making complete surgical resection impossible. We need to thoroughly understand the mechanisms underlying diffuse infiltration to develop effective therapies.

Methods

We integrated in vitro and in vivo functional assays, RNA sequencing, clinical, and expression information from public data sets to investigate the role of ADAM23 expression coupling astrocytoma's growth and motility.

Results

ADAM23 downregulation resulted in increased infiltration, reduced tumor growth, and improved overall survival in astrocytomas. Additionally, we show that ADAM23 deficiency induces γ-secretase (GS) complex activity, contributing to the production and deposition of the Amyloid-β and release of NICD. Finally, GS ablation in ADAM23-low astrocytomas induced a significant inhibitory effect on the invasive programs.

Conclusions

Our findings reveal a role for ADAM23 in regulating the balance between cell proliferation and invasiveness in astrocytoma cells, proposing GS inhibition as a therapeutic option in ADAM23 low-expressing astrocytomas.

Shear stress enhances anoikis resistance of cancer cells through ROS and NO suppressed degeneration of Caveolin-1

Circulating tumor cells (CTCs) acquire enhanced anti-anoikis abilities after experiencing flow shear stress in the circulatory system. Our previous study demonstrated that low shear stress (LSS) promotes anoikis resistance of human breast carcinoma cells via caveolin-1 (Cav-1)-dependent extrinsic and intrinsic apoptotic pathways. However, the underlying mechanism how LSS enhanced Cav-1 expression in suspended cancer cells remains unclear. Herein, we found that LSS induced redox signaling was involved in the regulation of Cav-1 level and anoikis resistance in suspension cultured cancer cells. Exposure of human breast carcinoma MDA-MB-231 cells to LSS (2 dyn/cm²) markedly induced ROS and ^•NO generation, which promoted the cell viability and reduced the cancer cell apoptosis. Furthermore, ROS and ^•NO scavenging inhibited the upregulation of Cav-1 by interfering ubiquitination, and suppressed the anoikis resistance of suspended tumor cells. These findings provide new insight into the mechanism by which LSS-stimulated ROS and ^•NO generation increases Cav-1 stabilization in suspended cancer cells through inhibition of ubiquitination and proteasomal degradation, which could be a potential target for therapy of metastatic tumors.

Prognostic value of tumour microenvironment-related genes by TCGA database in rectal cancer

Rectal cancer is a common malignant tumour and the progression is highly affected by the tumour microenvironment (TME). This study intended to assess the relationship between TME and prognosis, and explore prognostic genes of rectal cancer. The gene expression profile of rectal cancer was obtained from TCGA and immune/stromal scores were calculated by Estimation of Stromal and Immune cells in Malignant Tumors using Expression data (ESTIMATE) algorithm. The correlation between immune/stromal scores and survival time as well as clinical characteristics were evaluated. Differentially expressed genes (DEGs) were identified according to the stromal/immune scores, and the functional enrichment analyses were conducted to explore functions and pathways of DEGs. The survival analyses were conducted to clarify the DEGs with prognostic value, and the protein‐protein interaction (PPI) network was performed to explore the interrelation of prognostic DEGs. Finally, we validated prognostic DEGs using data from the Gene Expression Omnibus (GEO) database by PrognoScan, and we verified these genes at the protein levels using the Human Protein Atlas (HPA) databases. We downloaded gene expression profiles of 83 rectal cancer patients from The Cancer Genome Atlas (TCGA) database. The Kaplan‐Meier plot demonstrated that low‐immune score was associated with worse clinical outcome (P = .034), metastasis (M1 vs. M0, P = .031) and lymphatic invasion (+ vs. ‐, P < .001). A total of 540 genes were screened as DEGs with 539 up‐regulated genes and 1 down‐regulated gene. In addition, 60 DEGs were identified associated with overall survival. Functional enrichment analyses and PPI networks showed that the DEGs are mainly participated in immune process, and cytokine‐cytokine receptor interaction. Finally, 19 prognostic genes were verified by GSE17536 and GSE17537 from GEO, and five genes (ADAM23, ARHGAP20, ICOS, IRF4,MMRN1) were significantly different in tumour tissues compared with normal tissues at the protein level. In summary, our study demonstrated the associations between TME and prognosis as well as clinical characteristics of rectal cancer. Moreover, we explored and verified microenvironment‐related genes, which may be the potential key prognostic genes of rectal cancer. Further clinical samples and functional studies are needed to validate this finding.

Endocytosis of the non-catalytic ADAM23: Recycling and long half-life properties

A Disintegrin And Metalloprotease 23 (ADAM23) is a member of the ADAMs family of transmembrane proteins, mostly expressed in nervous system, and involved in traffic and stabilization of Kv1-potassium channels, synaptic transmission, neurite outgrowth, neuronal morphology and cell adhesion. Also, ADAM23 has been linked to human pathological conditions, such as epilepsy, cancer metastasis and cardiomyopathy. ADAM23 functionality depends on the molecule presence at the cell surface and along the secretory pathway, as expected for a cell surface receptor. Because endocytosis is an important functional regulatory mechanism of plasma membrane receptors and no information is available about the traffic or turnover of non-catalytic ADAMs, we investigated ADAM23 internalization, recycling and half-life properties. Here, we show that ADAM23 undergoes constitutive internalization from the plasma membrane, a process that depends on lipid raft integrity, and is redistributed to intracellular vesicles, especially early and recycling endosomes. Furthermore, we observed that ADAM23 is recycled from intracellular compartments back to the plasma membrane and thus has longer half-life and higher cell surface stability compared with other ADAMs. Our findings suggest that regulation of ADAM23 endocytosis/stability could be exploited therapeutically in diseases in which ADAM23 is directly involved, such as epilepsy, cancer progression and cardiac hypertrophy.

Dysregulation of adenosine kinase isoforms in breast cancer

Dysregulated adenosine signaling pathway has been evidenced in the pathogenesis of breast cancer. However, the role of adenosine kinase (ADK) in tumorigenesis remains unclear while it crucially regulates the removal and availability of adenosine. ADK has two isoforms that localize to discrete subcellular spaces: i.e., nuclear, long-isoform (ADK-L) and cytosolic, short-isoform (ADK-S). We hypothesized that these two ADK isoforms would be differentially expressed in breast cancer and may contribute to divergent cellular actions in cancer. In this study, we examined the expression profiles of ADK isoforms in breast cancer tissues from 46 patient and followed up with an in vitro investigation by knocking down the expression of ADK-L or ADK-S using CRISPR gene editing to evaluate the role of ADK isoform in cancer progression and metastasis of cultured triple-negative breast cancer cell line MDA-MB-231. We demonstrated that (i) ADK-L expression level was significantly increased in breast cancer tissues versus paired normal tissues adjacent to tumor, whereas the ADK-S expression levels were not significantly different between cancerous and normal tissues; (ii) CRISPR/Cas9-mediated downregulation of ADK isoforms, led to suppressed cellular proliferation, division, and migration of cultured breast cancer cells; (iii) ADK-L knockdown significantly upregulated gene expression of matrix metalloproteinase (ADAM23, 9.93-fold; MMP9, 24.58-fold) and downregulated expression of cyclin D2 (CCND2, -30.76-fold), adhesive glycoprotein THBS1 (-8.28-fold), and cystatin E/M (CST6, -16.32-fold). Our findings suggest a potential role of ADK-L in mitogenesis, tumorigenesis, and tumor-associated tissue remodeling and invasion; and the manipulation of ADK-L holds promise as a therapeutic strategy for aggressive breast cancer.

A disintegrin and metalloprotease 23 hypermethylation predicts decreased disease-free survival in low-risk breast cancer patients

A Disintegrin And Metalloprotease 23 (ADAM23), a member of the ADAM family, is involved in neuronal differentiation and cancer. ADAM23 is considered a possible tumor suppressor gene and is frequently downregulated in various types of malignancies. Its epigenetic silencing through promoter hypermethylation was observed in breast cancer (BC). In the present study, we evaluated the prognostic significance of ADAM23 promoter methylation for hematogenous spread and disease-free survival (DFS). Pyrosequencing was used to quantify ADAM23 methylation in tumors of 203 BC patients. Presence of circulating tumor cells (CTC) in their peripheral blood was detected by quantitative RT-PCR. Expression of epithelial (KRT19) or mesenchymal (epithelial-mesenchymal transition [EMT]-inducing transcription factors TWIST1, SNAI1, SLUG and ZEB1) mRNA transcripts was examined in CD45-depleted peripheral blood mononuclear cells. ADAM23 methylation was significantly lower in tumors of patients with the mesenchymal CTC (P = .006). It positively correlated with Ki-67 proliferation, especially in mesenchymal CTC-negative patients (P = .001). In low-risk patients, characterized by low Ki-67 and mesenchymal CTC absence, ADAM23 hypermethylation was an independent predictor of DFS (P = .006). Our results indicate that ADAM23 is likely involved in BC progression and dissemination of mesenchymal CTC. ADAM23 methylation has the potential to function as a novel prognostic marker and therapeutic target.

Targeting slug-mediated non-canonical activation of c-Met to overcome chemo-resistance in metastatic ovarian cancer cells

Metastasis-associated drug resistance accounts for high mortality in ovarian cancer and remains to be a major barrier for effective treatment. In this study, SKOV3/T4, a metastatic subpopulation of ovarian cancer SKOV3 cells, was enriched to explore potential interventions against metastatic-associated drug resistance. Quantitative genomic and functional analyses were performed and found that slug was significantly increased in the SKOV3/T4 subpopulation and contributed to the high resistance of SKOV3/T4. Further studies showed that slug activated c-Met in a ligand-independent manner due to elevated levels of fibronectin and provoked integrin α V function, which was confirmed by the significant correlation of slug and p-Met levels in 121 ovarian cancer patient samples. Intriguingly, c-Met inhibitor(s) exhibited greatly enhanced anti-cancer effects in slug-positive ovarian cancer models both in vitro and in vivo. Additionally, IHC analyses revealed that slug levels were highly correlated with reduced survival of ovarian cancer patients. Taken together, this study not only uncovers the critical roles of slug in drug resistance in ovarian cancer but also highlights a promising therapeutic strategy by targeting the noncanonical activation of c-Met in slug-positive ovarian cancer patients with poor prognosis.

Differential YAP expression in glioma cells induces cell competition and promotes tumorigenesis

Intratumor heterogeneity associates with cancer progression and may account for a substantial portion of therapeutic resistance. Although extensive studies have focused on the origin of the heterogeneity, biological interactions between heterogeneous malignant cells within a tumor are largely unexplored. Glioblastoma (GBM) is the most aggressive primary brain tumor. Here, we found that the expression of Yes-associated protein (YAP, also known as YAP1) is intratumorally heterogeneous in GBM. In a xenograft mouse model, differential YAP expression in glioma cells promotes tumorigenesis and leads to clonal dominance by cells expressing more YAP. Such clonal dominance also occurs in vitro when cells reach confluence in the two-dimensional culture condition or grow into tumor spheroids. During this process, growth of the dominant cell population is enhanced. In the tumor spheroid, such enhanced growth is accompanied by increased apoptosis in cells expressing less YAP. The cellular interaction during clonal dominance appears to be reminiscent of cell competition. RNA-seq analysis suggests that this interaction induces expression of tumorigenic genes, which may contribute to the enhanced tumor growth. These results suggest that tumorigenesis benefits from competitive interactions between heterogeneous tumor cells.

Low levels of ADAM23 expression in epithelial ovarian cancer are associated with poor survival

BACKGROUND

ADAM23, a member of the disintegrin and metalloprotease (ADAM) family, has been reported to be expressed in several types of tumours. Nevertheless, the exact role of ADAM23 in epithelial ovarian cancer (EOC) remains unclear. The aim of this study was to investigate ADAM23 expression in EOC and evaluate its clinicopathological and prognostic significance.

METHODS

Immunohistochemistry (IHC), western blot and real-time PCR (RT-PCR) were used to analyse ADAM23 expression in 133 EOC, 42 benign ovarian tumour and 35 healthy control samples. Moreover, we evaluated the expression of ADAM23 in both public database (Oncomine and Kaplan-Meier plotter). The association between ADAM23 expression and various clinicopathological parameters was analysed.

RESULTS

The levels of ADAM23 mRNA and protein expression were significantly lower in EOC tissues than in corresponding control tissues and benign ovarian tumours, verifying results from the Oncomine databases. The loss of ADAM23 expression was significantly correlated with an advanced International Federation of Gynecology and Obstetrics (FIGO) stage and lymph node metastasis. The IHC data in the EOC samples correlated with the RT-PCR data. Furthermore, patients with low ADAM23 expression had shorter progression-free survival (PFS) and overall survival (OS) than patients with high ADAM23 expression. The multivariate analysis indicated that ADAM23 was an independent predictor in patients with EOC.

CONCLUSIONS

Our results demonstrate that ADAM23 expression is likely involved in the progression of EOC and may provide potential diagnostic and prognostic information regarding EOC.

Beyond the Proteolytic Activity: Examining the Functional Relevance of the Ancillary Domains Using Tri-Dimensional (3D) Spheroid Invasion Assay

In this chapter, we describe a straightforward protocol to generate multicellular tumor spheroids (MTSs) and evaluate the role of specific genes in regulating cell invasiveness in real-time and tridimensional (3D) matrices. This approach provides advantages over other conventional invasion assays by offering intimate cell-cell and cell-ECM contacts and by mimicking the pathophysiological characteristics observed in tumor microenvironments (e.g., microregional gradients in glucose and O₂ concentrations and metabolic and proliferative tumor heterogeneity). We also provide an original and semiautomated approach to quantify MTS invasion using the freely available ImageJ software and plugins.

Migration-prone glioma cells show curcumin resistance associated with enhanced expression of miR-21 and invasion/anti-apoptosis-related proteins

In study, the expression patterns and functional differences between an original glioma cell population (U251 and U87) and sublines (U251-P10, U87-P10) that were selected to be migration-prone were investigated. The expressions levels of VEGF and intracellular adhesion molecule-1 (ICAM-1) were increased in the migration-prone sublines as well as in samples from patients with high-grade glioma when compared to those with low-grade glioma. In addition, cells of the migration-prone sublines showed increased expression of the oncogenic microRNA. miR-21, which was also associated with more advanced clinical pathological stages in the patient tissue specimens. Treatment of U251 cells with an miR-21 mimic dramatically enhanced the migratory activity and expression of anti-apoptotic proteins. Furthermore, treatment with curcumin decreased the miR-21 level and anti-apoptotic protein expression, and increased the expression of pro-apoptosis proteins and microtubule-associated protein light chain 3-II (LC3-II) in U251 cells. The migration-prone sublines showed decreased induction of cell death markers in response to curcumin treatment. Finally, U251-P10 cells showed resistance against curcumin treatment. These results suggest that miR-21 is associated with regulation of the migratory ability and survival in human glioma cells. These findings suggest novel mechanisms of malignancy and new potential combinatorial strategies for the management of malignant glioma.

CUSP9* treatment protocol for recurrent glioblastoma: aprepitant, artesunate, auranofin, captopril, celecoxib, disulfiram, itraconazole, ritonavir, sertraline augmenting continuous low dose temozolomide

CUSP9 treatment protocol for recurrent glioblastoma was published one year ago. We now present a slight modification, designated CUSP9*. CUSP9* drugs--aprepitant, artesunate, auranofin, captopril, celecoxib, disulfiram, itraconazole, sertraline, ritonavir, are all widely approved by regulatory authorities, marketed for non-cancer indications. Each drug inhibits one or more important growth-enhancing pathways used by glioblastoma. By blocking survival paths, the aim is to render temozolomide, the current standard cytotoxic drug used in primary glioblastoma treatment, more effective. Although esthetically unpleasing to use so many drugs at once, the closely similar drugs of the original CUSP9 used together have been well-tolerated when given on a compassionate-use basis in the cases that have come to our attention so far. We expect similarly good tolerability for CUSP9*. The combined action of this suite of drugs blocks signaling at, or the activity of, AKT phosphorylation, aldehyde dehydrogenase, angiotensin converting enzyme, carbonic anhydrase -2,- 9, -12, cyclooxygenase-1 and -2, cathepsin B, Hedgehog, interleukin-6, 5-lipoxygenase, matrix metalloproteinase -2 and -9, mammalian target of rapamycin, neurokinin-1, p-gp efflux pump, thioredoxin reductase, tissue factor, 20 kDa translationally controlled tumor protein, and vascular endothelial growth factor. We believe that given the current prognosis after a glioblastoma has recurred, a trial of CUSP9* is warranted.