The era of multigene panels comes? The clinical utility of Oncotype DX and MammaPrint

The AJCC Cancer Staging Manual, eighth edition published in late 2016, will become the new global guideline for cancer diagnosis and treatment from January 1, 2018. The new edition for the tumor staging system has numerous updates, including building up the prognostic stage group of tumors for the first time and adding a large number of non-anatomical factors into the prognostic evaluation. Oncotype DX and MammaPrint are two of the genomic predictors that will be part of routine clinical practice in the future. Numerous studies have proved the clinical utility of multigene panels in predicting clinical outcome and treatment response. Here we present our review of the studies on these multigene panels and their application to breast cancer

The role of JAM-B in cancer and cancer metastasis (Review)

The junctional adhesion molecule B (JAM-B) is a multifunctional transmembrane protein, which belongs to the immunoglobulin superfamily (IgSF). JAM-B is localized to cell-cell contacts and enriched at cell junctions in epithelial and endothelial cells, as well as on the surface of erythrocytes, leukocytes, and platelets. Recent research in this field has shown that JAM-B plays an important role in numerous cellular processes, such as tight junction assembly, spermatogenesis, regulation of paracellular permeability, leukocytic transmigration, angiogenesis, tumor metastasis and cell proliferation. This study provides a new research direction for the diagnosis and treatment of relevant diseases. In this review, we briefly focus on what is currently known about the structure, function, and mechanism of JAM-B, with particular emphasis on cancer

Epithelial protein lost in neoplasm-α (EPLIN-α) is a potential prognostic marker for the progression of epithelial ovarian cancer

Epithelial protein lost in neoplasm-α (EPLIN-α) is a cytoskeletal protein whose expression is often lost or is aberrant in cancerous cells and tissues and whose loss is believed to be involved in aggressive phenotypes. This study examined this molecule in human epithelial ovarian tissues and investigated the cellular impact of EPLIN-α on ovarian cancer cells (EOC), SKOV3 and COV504. The expression of EPLIN-α in human ovarian tissues and EOC was assessed at both the mRNA and protein levels using reverse transcription-PCR (RT-PCR) and immunohistochemistry, respectively. In vitro assays for cellular matrix adhesion and migration (confirmed by an electrical cell substrate impedance sensing (ECIS) based method), invasion and cell growth were employed in order to assess the biological influence of EPLIN-α expression on EOC cells. Immunohistochemical analysis of ovarian cancer samples demonstrated that only a small number expressed EPLIN-α protein. Downregulation of EPLIN-α protein in EOC cell lines increased the growth, invasion, adhesion and migration in vitro. This EPLIN-α downregulation may have a prognostic value. From these data, we conclude that downregulation of EPLIN-α may be associated with poorer patient prognosis, and that this molecule appears to play a tumour suppressor role by inhibition of EOC growth and migration

Effect of junctional adhesion molecule-2 expression on cell growth, invasion and migration in human colorectal cancer

The junctional adhesion molecule (JAMs) family belongs to the immunoglobulin subfamily involved in the formation of tight junctions (TJ) in both endothelial and epithelial cells. Aberrant expression of JAM-2 is associated with cancer progression but little work has been carried out in discovering how this affects changes in cell behaviour. The present study aimed to examine the expression of JAM-2 in human colon cancer specimens and cell lines and its role in the development of colon cancer. JAM-2 expression in human colon cancer specimens (normal, n=75; cancer, n=94) and cell lines was analysed using quantitative real-time PCR and conventional RT-PCR. Colon cancer cells were stably transfected with a mammalian expression vector to overexpress JAM-2-Flag. The effect on growth, adhesion and migration following overexpression of JAM-2 was then investigated using in vitro models. TJ function was assessed using a trans-epithelial resistance assay (TER, with an EVOM voltammeter). JAM-2 was lowly expressed in colon cancer cells such as RKO, HT115. JAM-2 overexpression in RKO cells (RKO-JAM-2) and HT115 cells (HT115-JAM-2) showed retarded adhesion (P<0.05). An in vivo tumour model showed that RKO-JAM-2 had significantly reduced growth (P<0.05), invasion (P<0.05) and migration (P<0.05) as well as in HT115-JAM-2, except on proliferation and migration. Expression of JAM-2 resulted in a significant increase in TER and decrease in permeability of polarized monolayers (P<0.05). Further analysis of JAM-2 transcript levels against clinical aspects demonstrated that the decreasing JAM-2 expression correlated to disease progression, metastasis and poor survival. Taken together, JAM-2 may function as a putative tumour suppressor in the progression and metastasis of colorectal cance

Role of the WASP and WAVE family proteins in breast cancer invasion and metastasis

The Wiskott–Aldrich syndrome protein (WASP) and WASP family verprolin-homologous protein (WAVE) family are a group of molecules that form a key link between GTPases and the actin cytoskeleton. The role of WASP/WAVE family proteins in the control of actin polymerization through activation of the actin-related protein 2/3 complex is critical in the formation of the actin-based membrane protrusions seen in cell migration and invasion. For this reason, the activity of the WASP/WAVE family in cancer cell invasion and migration has been of great interest in recent years. Many reports have highlighted the potential of targeting the WASP/WAVE family as a therapy for the prevention of cancer progression, in particular breast cancer. This review focuses on the role of the WASP/WAVE family in breast cancer cell invasion and migration and how this relates to the molecular mechanisms of WASP/WAVE activity, their exact contributions to the stages of cancer progression, and how this can lead to the development of anticancer drugs that target the WASP/WAVE family and related pathways

Metastasis tumour suppressor-1 and the aggressiveness of prostate cancer cells

Previous studies have suggested that metastasis tumour suppressor-1 (MTSS1) plays a key role in cancer metastasis. Firstly, in this study we assessed MTSS1 expression levels in prostate cancer cell lines to reveal any changes in cell properties. Secondly, we aimed to clarify the cellular function of MTSS1 in prostate cancer cells. MTSS1 expression levels were assessed in different types of cancer cell lines through the RT-PCR analysis technique. The influence of MTSS1 was further examined via biological overexpression and knockdown in the prostate cancer cell lines. Two prostate cell lines were chosen for either knockdown or overexpression of the MTSS1 gene. The overexpression of MTSS1 in PC-3 human prostate cancer cells significantly suppressed the migratory, growth and adherence properties of the cells (p<0.01). By contrast, the knockdown of MTSS1 in DU-145 human prostate cancer cells dramatically enhanced these properties (p<0.001). We concluded that MTSS1 demonstrates the ability to play a role in controlling the metastatic nature of prostate cancer cells

Biological influence of brain-derived neurotrophic factor (BDNF) on colon cancer cells

Brain-derived neurotrophic factor (BDNF) has been observed to be elevated in solid tumors including colorectal cancer. The present study aimed to investigate the effect of modulation of BDNF at the transcription level on the cellular function of colorectal cells and to increase our understanding of its biological role in human colon cancer. An investigation of a cohort of human colorectal tissues (tumor n=66; normal n=88) using quantitative PCR and immunohistochemistry demonstrated that BDNF is aberrantly expressed in human colon cancer and a significantly raised level of BDNF is associated with its stage at diagnosis. The expression profile of BDNF in human colon cancer cell lines was evaluated using RT‑PCR. A set of anti-BDNF ribozymes were used to transfect colon cancer cells in order to generate BDNF knockdown cells to evaluate the effect on growth and apoptosis. BDNF gene transcripts were successfully detected in the colon cancer cell lines, Caco‑2 and HRT18. BDNF knockdown in Caco‑2 and HRT18 cell lines resulted in decreased rates of growth and proliferation. Analysis of apoptosis showed that cell apoptosis was increased. It is concluded that BDNF, a neurotrophic growth factor aberrantly expressed in cancers such as colon cancer, has a profound impact on the cellular behavior of colon cancer cells and that BDNF is associated with a reduction in the apoptosis of colon cancer. BDNF is therefore a potential therapeutic target in colon cancer and its effect in human colon cancer requires further investigation

Biological influence of brain-derived neurotrophic factor on breast cancer cells

Brain-derived neurotrophic factor (BDNF) is a member of the neurotrophin superfamily which has been indicated in the pathophysiology of the nervous system and is important in a number of neurological and psychological conditions. Recently, BDNF was also shown to play a role in the development and progression of solid tumour myeloma. It has been reported that BDNF is aberrantly expressed in human breast cancer and that a raised level of BDNF is associated with poor clinical outcome and reduced survival. The present study investigated the role of BDNF in human breast cancer. A panel of human breast cancer cells was used and the expression profile of BDNF was evaluated using RT-PCR. We constructed a set of anti-BDNF transgenes which were used to transfect breast cancer cells in order to generate BDNF knocked down cells. The impact of BDNF knockdown on growth and apoptosis was evaluated. Statistical analysis was performed using SPSS. P<0.05 was considered statistically significant. BDNF gene transcripts were successfully detected in the breast cancer cell lines MCF-7, MDA-MB-231 and ZR75-1 MDA-MB-231 and MCF-7 wild-type cells were subject to transfection of anti-BDNF transgenes, followed by the establishment of BDNF knocked down sublines. Knockdown of BDNF in MDA-MB-231 and MCF-7 cell lines resulted in decreased rates of growth and proliferation. Analysis of apoptosis showed that cell apoptosis was increased in cells stably transfected with ribozymes for BDNF compared with the vector control. It is concluded that BDNF, a neurotrophic growth factor aberrantly expressed in cancers such as breast cancer, has a profound impact on the cellular behaviour of breast cancer cells and that BDNF is associated with a reduction of the apoptosis of breast cancer. BDNF is, therefore, a potential therapeutic target in breast cancer and its effect in human breast cancer requires further investigation

Loss of occludin leads to the progression of human breast cancer

Occludin is an integral membrane protein localised at tight junctions (TJs). It has become clear that the TJ is an important structure that cancer cells must overcome in order to metastasize successfully. The purpose of this study was to elucidate the importance of the expression of occludin in human breast cancer. Human tissues and breast cancer cell lines were amplified for functional regions of occludin. Tumour tissues showed truncated and/or variant signals. There was also considerable variation in the expression of occludin in the 10 human breast cancer cell lines investigated. Western blotting demonstrated that variants in the MDA-MB-231 and MCF-7 human breast cancer cell lines did not fit the expected occludin signals for changes in phosphorylation status. Immunostaining showed similarly disparate levels of expression. Ribozyme knockdown resulted in increased invasion, reduced adhesion and significantly reduced TJ functions. Q-RT-PCR analysis of 124 tumour and 33 background human breast tissues showed occludin to be significantly decreased in patients with metastatic disease. Immunohistochemical staining showed a decreased expression of occludin in the tumour sections. This study demonstrates for the first time that occludin is differentially expressed in human breast tumour tissues and cell lines. This loss of or aberrant expression has clear repercussions as to the importance of occludin in maintaining TJ integrity in breast tissues. Such inappropriate expression could play a part in breast cancer development

Claudin-5 is involved in breast cancer cell motility through the N-WASP and ROCK signalling pathways

Background: Recent studies have shown dysregulation in TJ structure of several cancers including breast. Claudin-5 is a protein member of the TJ structure expressed in both endothelial and epithelial cells. This study examined the level of expression and distribution of Claudin-5 in human breast cancer tissues and the effect of knockdown and forced expression of Claudin-5 in the MDA-MB-231 breast cancer cell line. Methods: Immunohistochemistry and quantitative-PCR were used to analyse patient tissue samples. The Claudin-5 gene was cloned and overexpressed or knocked down using ribozyme technology in human breast cancer cells. Changes in function were assessed using in vitro assays for invasion, growth, adhesion, wounding, motility, transepithelial resistance and electric cell-substrate impedance sensing. Changes in cell behaviour were achieved through the use of Hepatocyte Growth factor (HGF) which we have shown to affect TJ function and expression of TJ proteins. In addition, an in vivo model was used for tumour growth assays. Results data was analyzed using a Students two sample t-test and by Two-way Anova test when the data was found to be normalized and have equal variances. In all cases 95% confidence intervals were used. Results: Patients whose tumours expressed high levels of Claudin-5 had shorter survival than those with low levels (p = 0.004). Investigating in vitro the effect of altering levels of expression of Claudin-5 in MDA-MB-231cells revealed that the insertion of Claudin-5 gene resulted in significantly more motile cells (p < 0.005). Low levels of Claudin-5 resulted in a decrease in adhesion to matrix (p < 0.001). Furthermore, a possible link between Claudin-5 and N-WASP, and Claudin-5 and ROCK was demonstrated when interactions between these proteins were seen in the cells. Moreover, followed by treatment of N-WASP inhibitor (Wiskostatin) and ROCK inhibitor (Y-27632) cell motility was assessed in response to the inhibitors. Results showed that the knockdown of Claudin-5 in MDA-MB-231 masked their response after treatment with N-WASP inhibitor; however treatment with ROCK inhibitor did not reveal any differences in motility in this cell line. Conclusions: This study portrays a very new and interesting role for Claudin-5 in cell motility involving the N-WASP signalling cascade indicating a possible role for Claudin-5 in the metastasis of human breast cancer