DEAD-box helicase DP103 defines metastatic potential of human breast cancers

Despite advancement in breast cancer treatment, 30% of patients with early breast cancers experience relapse with distant metastasis. It is a challenge to identify patients at risk for relapse; therefore, the identification of markers and therapeutic targets for metastatic breast cancers is imperative. Here, we identified DP103 as a biomarker and metastasis-driving oncogene in human breast cancers and determined that DP103 elevates matrix metallopeptidase 9 (MMP9) levels, which are associated with metastasis and invasion through activation of NF-κB. In turn, NF-κB signaling positively activated DP103 expression. Furthermore, DP103 enhanced TGF-β-activated kinase-1 (TAK1) phosphorylation of NF-κB-activating IκB kinase 2 (IKK2), leading to increased NF-κB activity. Reduction of DP103 expression in invasive breast cancer cells reduced phosphorylation of IKK2, abrogated NF-κB-mediated MMP9 expression, and impeded metastasis in a murine xenograft model. In breast cancer patient tissues, elevated levels of DP103 correlated with enhanced MMP9, reduced overall survival, and reduced survival after relapse. Together, these data indicate that a positive DP103/NF-κB feedback loop promotes constitutive NF-κB activation in invasive breast cancers and activation of this pathway is linked to cancer progression and the acquisition of chemotherapy resistance. Furthermore, our results suggest that DP103 has potential as a therapeutic target for breast cancer treatment.

GAP-independent functions of DLC1 in metastasis.

Metastases are responsible for most cancer-related deaths. One of the hallmarks of metastatic cells is increased motility and migration through extracellular matrixes. These processes rely on specific small GTPases, in particular those of the Rho family. Deleted in liver cancer-1 (DLC1) is a tumor suppressor that bears a RhoGAP activity. This protein is lost in most cancers, allowing malignant cells to proliferate and disseminate in a Rho-dependent manner. However, DLC1 is also a scaffold protein involved in alternative pathways leading to tumor and metastasis suppressor activities. Recently, substantial information has been gathered on these mechanisms and this review is aiming at describing the potential and known alternative GAP-independent mechanisms allowing DLC1 to impair migration, invasion, and metastasis formation.

Assessment of the anti-genotoxic, anti-proliferative, and anti-metastatic potential of crude watercress extract in human colon cancer cells

Although it is known to be a rich source of the putative anti-cancer chemicals isothiocyanates, watercress has not been extensively studied for its cancer preventing properties. The aim of this study was to investigate the potential chemoprotective effects of crude watercress extract toward three important stages in the carcinogenic process, namely initiation, proliferation, and metastasis (invasion) using established in vitro models. HT29 cells were used to investigate the protective effects of the extract on DNA damage and the cell cycle. The extract was not genotoxic but inhibited DNA damage induced by two of the three genotoxins used, namely hydrogen peroxide and fecal water, indicating the potential to inhibit initiation. It also caused an accumulation of cells in the S phase of the cell cycle indicating (possible) cell cycle delay at this stage. The extract was shown to significantly inhibit invasion of HT115 cells through matrigel. Component analysis was also carried out in an attempt to determine the major phytochemicals present in both watercress leaves and the crude extract. In conclusion, the watercress extract proved to be significantly protective against the three stages of the carcinogenesis process investigated.

Potential anti-cancer effects of virgin olive oil phenols on colorectal carcinogenesis models in vitro

The traditional Mediterranean diet is thought to represent a healthy lifestyle; especially given the incidence of several cancers including colorectal cancer is lower in Mediterranean countries compared to Northern Europe. Olive oil, a central component of the Mediterranean diet, is believed to beneficially affect numerous biological processes. We used phenols extracted from virgin olive oil on a series of in vitro systems that model important stages of colon carcinogenesis. The effect the extract on DNA damage induced by hydrogen peroxide was measured in HT29 cells using single cell microgel-electrophoresis. A significant anti-genotoxic linear trend (p=0.011) was observed when HT29 cells were pre-incubated with olive oil phenols (0, 5, 10, 25, 50, 75, 100 microg/ml) for 24 hr, then challenged with hydrogen peroxide. The olive oil phenols (50, 100 microg/ml) significantly (p=0.004, p=0.002) improved barrier function of CACO2 cells after 48 hr as measured by trans-epithelial resistance. Significant inhibition of HT115 invasion (p<0.01) was observed at olive oil phenols concentrations of 25, 50, 75, 100 microg/ml using the matrigel invasion assay. No effect was observed on HT115 viability over the concentration range 0, 25, 50 75, 100 microg/ml after 24 hr, although 75 and 100 microg/ml olive oil phenols significantly inhibited HT115 cell attachment (p=0.011, p=0.006). Olive oil phenols had no significant effect on metastasis-related gene expression in HT115 cells. We have demonstrated that phenols extracted from virgin olive oil are capable of inhibiting several stages in colon carcinogenesis in vitro.

α2β1 integrin affects metastatic potential of ovarian carcinoma spheroids by supporting disaggregation and proteolysis

Background: Ovarian cancer is characterized by a wide-spread intra-abdominal metastases which represents a major clinical hurdle in the prognosis and management of the disease. A significant proportion of ovarian cancer cells in peritoneal ascites exist as multicellular aggregates or spheroids. We hypothesize that these cellular aggregates or spheroids are invasive with the capacity to survive and implant on the peritoneal surface. This study was designed to elucidate early inherent mechanism(s) of spheroid survival, growth and disaggregation required for peritoneal metastases.

Methods: In this study, we determined the growth pattern and adhesive capacity of ovarian cancer cell lines (HEY and OVHS1) grown as spheroids, using the well established liquid overlay technique, and compared them to a normal ovarian cell line (IOSE29) and cancer cells grown as a monolayer. The proteolytic capacity of these spheroids was compared with cells grown as a monolayer using a gelatin zymography assay to analyze secreted MMP-2/9 in conditioned serum-free medium. The disaggregation of cancer cell line spheroids was determined on extracellular matrices (ECM) such as laminin (LM), fibronectin (FN) and collagen (CI) and the expression of α2, α3, αv, α6 and β1 interin was determined by flow cytometric analysis. Neutralizing antibodies against α2, β1 subunits and α2β1 integrin was used to inhibit disaggregation as well as activation of MMPs in spheroids.

Results: We demonstrate that ovarian cancer cell lines grown as spheroids can sustain growth for 10 days while the normal ovarian cell line failed to grow beyond 2 days. Compared to cells grown as a monolayer, cancer cells grown as spheroids demonstrated no change in adhesion for up to 4 days, while IOSE29 cells had a 2–4-fold loss of adhesion within 2 days. Cancer cell spheroids disaggregated on extracellular matrices (ECM) and demonstrated enhanced expression of secreted pro-MMP2 as well as activated MMP2/MMP9 with no such activation of MMP's observed in monolayer cells. Flow cytometric analysis demonstrated enhanced expression of α2 and diminution of α6 integrin subunits in spheroids
versus monolayer cells. No change in the expression of α3, αv and β1 subunits was evident. Conversely, except for αv integrin, a 1.5–7.5-fold decrease in α2, α3, α6 and β1 integrin subunit expression was observed in IOSE29 cells within 2 days. Neutralizing antibodies against α2, β1 subunits and α2β1 integrin inhibited disaggregation as well as activation of
MMPs in spheroids.

Conclusion: Our results suggest that enhanced expression of α2β1 integrin may influence spheroid disaggregation and
proteolysis responsible for the peritoneal dissemination of ovarian carcinoma. This may indicate a new therapeutic target
for the suppression of the peritoneal metastasis associated with advanced ovarian carcinomas.

Role of the EpCAM (CD326) in prostate cancer metastasis and progression

Despite significant advances in surgery, radiotherapy and chemotherapy to treat prostate cancer (CaP), many patients die of secondary disease (metastases). Current therapeutic approaches are limited, and there is no cure for metastatic castration-resistant prostate cancer (CRPC). Epithelial cell adhesion molecule (EpCAM, also known as CD326) is a transmembrane glycoprotein that is highly expressed in rapidly proliferating carcinomas and plays an important role in the prevention of cell–cell adhesion, cell signalling, migration, proliferation and differentiation. Stably and highly expressed EpCAM has been found in primary CaP tissues, effusions and CaP metastases, making it an ideal candidate of tumour-associated antigen to detect metastasis of CaP cells in the circulation as well as a promising therapeutic target to control metastatic CRPC disease. In this review, we discuss the implications of the newly identified roles of EpCAM in terms of its diagnostic and metastatic relevance to CaP. We also summarize EpCAM expression in human CaP and EpCAM-mediated signalling pathways in cancer metastasis. Finally, emerging and innovative approaches to the management of the disease and expanding potential therapeutic applications of EpCAM for targeted strategies in future CaP therapy will be explored.

Molecular imaging of metabolism in cancer metastasis

Cancer progression is characterised by extensive metabolic reprogramming. Renewed enthusiasm in this field has been sparked in part by the realisation that metabolic pathways, oncogenes and tumour suppressors are intimately linked and regulate tumour growth and metastasis through complex reciprocal interactions. The identification of key pathways and enzymes regulating metabolism in cancer cells provides new opportunities for cancer therapy. This has motivated the development of several specific inhibitors targeting metabolic pathways and their therapeutic evaluation in pre-clinical models or in cancer patients. The unravelling of metabolic pathways associated with cancer progression has also highlighted the extensive metabolic heterogeneity that exists between, and within, each cancer type as well as between metastatic sites. The translation of these findings into personalised therapy remains a considerable challenge. To this end, the use of positron emission tomography to non-invasively visualise tumour metabolism is likely to facilitate the implementation of and assessment of new targeted therapies. Here, we briefly review the key metabolic changes associated with cancer progression and discuss recent advances in the field of positron emission tomography for metabolic imaging of cancer and their potential to improve the clinical management of cancer patients.

A comparison of novel organoiridium(III) complexes and their ligands as a potential treatment for prostate cancer

A range of 1,4-substituted 2-pyridyl-N-phenyl triazoles were synthesised and evaluated for their antiproliferative properties against lymph node cancer of the prostate (LNCaP) and bone metastasis of prostate cancer (PC-3) cells. Excellent-to-low IC50 values were determined (5.6-250 μM), and a representative group of 4 ligands were then complexed to iridium(III) giving highly luminescent species. Re-evaluation of these compounds against both cell lines was then undertaken and improved potency (up to 72-fold) was observed, giving IC50 values of 0.36-11 μM for LNCaP and 0.85-5.9 μM for PC-3. Preliminary screens for in vivo toxicity were conducted using a zebrafish model showing a wide range of induced toxicity depending of the compound evaluated. Apoptosis and Caspase-3 levels were also determined and showed no statistical difference between some of the treated specimens and the controls. This study may identify novel therapeutic agents for advanced stage of prostate cancer in humans.

Absence of TGF-beta RII predicts bone and lung metastasis and is associated with poor prognosis in stage III breast tumors

In the case of operated breast cancer (BC), prognostic markers help to determine if the patient needs additional treatment and predictive markers help the clinician to decide which treatment to use. Thus, a better knowledge of known predictive and prognostic markers and the identification of new markers, may improve the treatment of BC patients. The transforming growth factor-beta type II receptor (TGF-beta RII), a main receptor of transforming growth factor beta pathway, is a potential new prognostic marker. The aims of the present study were to investigate both the predictive and prognostic impact of TGF-beta RII in BC samples. TGF-beta RII protein expression was evaluated using immunohistochemistry on a tissue microarray containing 110 TNM stage III BC samples obtained prior to doxorubicin-based neoadjuvant chemotherapy (NAC). Our results demonstrate that TGF-beta RII did not predict the response to NAC. on the other hand, an association between TGF-beta RII-negative tumor and higher risk of metastasis to lungs and bones was verified. TGF-beta RII negativity was an independent prognostic factor for decreased disease-free and overall survival.

TWIST1 Is a Molecular Marker for a Poor Prognosis in Oral Cancer and Represents a Potential Therapeutic Target

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Molecular markers of angiogenesis and metastasis in lines of oral carcinoma after treatment with melatonin

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Inflammation and cancer: role of Annexin A1 and FPR2/ALX in proliferation and metastasis in human laryngeal squamous cell carcinoma

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Predominant Rab-GTPase amplicons contributing to oral squamous cell carcinoma progression to metastasis

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Tumor lymphangiogenesis and metastasis to lymph nodes induced by cancer cell expression of podoplanin

The membrane glycoprotein podoplanin is expressed by several types of human cancers and might be associated with their malignant progression. Its exact biological function and molecular targets are unclear, however. Here, we assessed the relevance of tumor cell expression of podoplanin in cancer metastasis to lymph nodes, using a human MCF7 breast carcinoma xenograft model. We found that podoplanin expression promoted tumor cell motility in vitro and, unexpectedly, increased tumor lymphangiogenesis and metastasis to regional lymph nodes in vivo, without promoting primary tumor growth. Importantly, high cancer cell expression levels of podoplanin correlated with lymph node metastasis and reduced survival times in a large cohort of 252 oral squamous cell carcinoma patients. Based on comparative transcriptional profiling of tumor xenografts, we identified endothelin-1, villin-1, and tenascin-C as potential mediators of podoplanin-induced tumor lymphangiogenesis and metastasis. These unexpected findings identify a novel mechanism of tumor lymphangiogenesis and metastasis induced by cancer cell expression of podoplanin, suggesting that reagents designed to interfere with podoplanin function might be developed as therapeutics for patients with advanced cancer.

Intratumoral budding as a potential parameter of tumor progression in mismatch repair-proficient and mismatch repair-deficient colorectal cancer patients

In colorectal cancer, tumor budding at the invasive front (peritumoral budding) is an established prognostic parameter and decreased in mismatch repair-deficient tumors. In contrast, the clinical relevance of tumor budding within the tumor center (intratumoral budding) is not yet known. The aim of the study was to determine the correlation of intratumoral budding with peritumoral budding and mismatch repair status and the prognostic impact of intratumoral budding using 2 independent patient cohorts. Following pancytokeratin staining of whole-tissue sections and multiple-punch tissue microarrays, 2 independent cohorts (group 1: n = 289; group 2: n = 222) with known mismatch repair status were investigated for intratumoral budding and peritumoral budding. In group 1, intratumoral budding was strongly correlated to peritumoral budding (r = 0.64; P < .001) and less frequent in mismatch repair-deficient versus mismatch repair-proficient cases (P = .177). Sensitivity and specificity for lymph node positivity were 72.7% and 72.1%. In mismatch repair-proficient cancers, high-grade intratumoral budding was associated with right-sided location (P = .024), advanced T stage (P = .001) and N stage pN (P < .001), vascular invasion (P = .041), infiltrating tumor margin (P = .003), and shorter survival time (P = .014). In mismatch repair-deficient cancers, high intratumoral budding was linked to higher tumor grade (P = .004), vascular invasion (P = .009), infiltrating tumor margin (P = .005), and more unfavorable survival time (P = .09). These associations were confirmed in group 2. High-grade intratumoral budding was a poor prognostic factor in univariate (P < .001) and multivariable analyses (P = .019) adjusting for T stage, N stage distant metastasis, and adjuvant therapy. These preliminary results on 511 patients show that intratumoral budding is an independent prognostic factor, supporting the future investigation of intratumoral budding in larger series of both preoperative and postoperative rectal and colon cancer specimens.