Epithelial Protein Lost in Neoplasm, EPLIN, the Cellular and Molecular Prospects in Cancers

Epithelial Protein Lost In Neoplasm (EPLIN), also known as LIMA1 (LIM Domain And Actin Binding 1), was first discovered as a protein differentially expressed in normal and cancerous cell lines. It is now known to be key to the progression and metastasis of certain solid tumours. Despite a slow pace in understanding the biological role in cells and body systems, as well as its clinical implications in the early years since its discovery, recent years have witnessed a rapid progress in understanding the mechanisms of this protein in cells, diseases and indeed the body. EPLIN has drawn more attention over the past few years with its roles expanding from cell migration and cytoskeletal dynamics, to cell cycle, gene regulation, angiogenesis/lymphangiogenesis and lipid metabolism. This concise review summarises and discusses the recent progress in understanding EPLIN in biological processes and its implications in cancer

EPLIN, a putative tumour suppressor in colorectal cancer, implications in drug resistance

Colorectal cancer is a serious threat to human health. Poor prognosis and frequently reported drug resistance urges research into novel biomarkers and mechanisms to aid in the understanding of the development and progression of colorectal cancer and to optimise therapeutic strategies. In the current study, we investigated the roles of a putative tumour suppressor, EPLIN, in colorectal cancer. Our clinical colorectal cancer cohort and online databases revealed a downregulation of EPLIN in colorectal cancer tissues compared with normal tissues. The reduced expression of EPLIN was associated with poor clinical outcomes of patients. In vitro cellular function assays showed that EPLIN elicited an inhibitory effect on cellular growth, adhesion, migration and invasion. Utilising a protein microarray on protein samples from normal and tumour patient tissues suggested HSP60, Her2 and other signalling events were novel potential interacting partners of EPLIN. It was further revealed that EPLIN and HSP60 were negative regulators of Her2 in colorectal cancer cells. The clinical cohort also demonstrated that expression of HSP60 and Her2 affected clinical outcomes, but most interestingly the combination of EPLIN, HSP60 and Her2 was able to identify patients with the most unfavourable clinical outcome by independently predicting patient overall survival and disease free survival. Furthermore, EPLIN and HSP60 exhibited potential to regulate cellular response to chemotherapeutic and EGFR/Her2 targeted therapeutic agents. In conclusion, EPLIN is an important prognostic factor for patients with colon cancer and reduced EPLIN in CRC contributes to aggressive traits of CRC cells and their responses to chemotherapeutic drugs. Collectively, EPLIN is a pivotal factor for the development and progression of colorectal cancer and has important clinical and therapeutic values in this cancer type

Expression of ALCAM in clinical colon cancer and relationship with patients' treatment responses

Background/Aim: Activated leukocyte cell adhesion molecule (ALCAM) plays an important role in cancer via its homotypical and heterotypical interactions with ALCAM or other proteins and can also mediate cell-cell interactions. The present study investigated the expression of ALCAM in relation to epithelial–to–mesenchymal transition (EMT) markers and its downstream signal proteins including Ezrin-Moesin-Radixin (ERM), in clinical colon cancer and in the progression of the disease. Materials and Methods: Expression of ALCAM was determined in a clinical colon cancer cohort and assessed against the clinical pathological factors and outcome, together with the expression patterns of the ERM family and EMT markers. ALCAM protein was detected using immunohistochemistry. Cell line models, with ALCAM knock-down and over-expression, were established and used to test cells’ responses to drugs. Results: Tumours from patients who had distant metastasis and died of colon cancer had low levels of ALCAM. Dukes B and C tumours also had lower ALCAM expression than Dukes A tumours. Patients with high levels of ALCAM had a significantly longer overall and disease-free survival than those with lower ALCAM levels (p=0.040 and p=0.044). ALCAM is not only significantly correlated with SNAI1 and TWIST, also positively correlated with SNAI2. ALCAM enhanced the adhesiveness of colorectal cancer, an effect inhibited by both sALCAM and SRC inhibitors. Finally, high ALCAM expression rendered cells resistant, especially to 5-fluorouracil. Conclusion: Reduced expression of ALCAM in colon cancer is an indicator of disease progression and a poor prognostic indicator for patient’s survival. However, ALCAM can enhance the adhesion ability of cancer cells and render them resistant to chemotherapy drugs

EPLIN expression in gastric cancer and impact on prognosis and chemoresistance

Epithelial protein lost in neoplasm (EPLIN) has been implicated as a suppressor of cancer progression. The current study explored EPLIN expression in clinical gastric cancer and its association with chemotherapy resistance. EPLIN transcript expression, in conjunction with patient clinicopathological information and responsiveness to neoadjuvant chemotherapy (NAC), was explored in two gastric cancer cohorts collected from the Beijing Cancer Hospital. Kaplan-Meier survival analysis was undertaken to explore EPLIN association with patient survival. Reduced EPLIN expression was associated with significant or near significant reductions of overall, disease-free, first progression or post-progression survival in the larger host cohort and Kaplan Meier plotter datasets. In the larger cohort EPLIN expression was significantly higher in the combined T1 + T2 gastric cancer group compared to the T3 + T4 group and identified to be an independent prognostic factor of disease-free survival and overall survival by multivariate analysis. In the smaller, NAC cohort, EPLIN expression was found to be significantly lower in tumour tissues than in paratumour tissues. EPLIN expression was significantly associated with responsiveness to chemotherapy which contributes to overall survival. Together, EPLIN appears to be a prognostic factor and may be associated with patient sensitivity to NAC

Expression of Claudin-9 (CLDN9) in breast cancer, the clinical significance in connection with its subcoat anchorage proteins ZO-1 and ZO-3 and impact on drug resistance

(1) Introduction: Claudin-9 (CLDN9) is a member of the claudin protein family, a critical transmembrane protein family for tight junctions that are implemented in the progression of numerous cancer types. The present study investigated the role that CLDN9, along with the subcoat proteins, Zonula Occludens (ZOs), plays in clinical breast cancer and subsequent impact on drug response of patients. (2) Methods: CLDN9 protein and CLDN9 transcript were determined and correlated with clinical and pathological indicators, together with the status of hormonal receptors. The levels of CLDN9 transcript were also assessed against the therapeutic responses of the patients to chemotherapies by using a dataset from the TCGA database. Breast cancer cell models, representing different molecular subtypes of breast cancer, with differential expression of CLDN9 were created and used to assess the biological impact and response to chemotherapeutic drugs. (3) Results: Breast cancer tissues expressed significantly higher levels of the CLDN9, with the high levels being associated with shorter survival. CLDN9 was significantly correlated with its anchorage proteins ZO-1 and ZO-3. Integrated expression of CLDN9, ZO-1 and ZO-3 formed a signature that was significantly linked to overall survival (OS) (p = 0.013) and relapse-free survival (RFS) (p = 0.024) in an independent matter. CLDN9 transcript was significantly higher in patients who were resistant to chemotherapies (p < 0.000001). CLDN9 connection to chemoresistance was particularly prominent in patients of ER-positive (ER(+)), Her-2-negative((Her-2(−)), ER(+)/Her-2(−) and triple-negative breast cancers (TNBCs), but not in patients with HER-2-positive tumors. In Her-2-negative MCF7 and MDA-MB-231 cancer cells, loss of CLDN9 significantly increased sensitivity to several chemotherapeutic drugs including paclitaxel, gemcitabine and methotrexate, which was not seen in Her-2(+) SKBR3 cells. However, suppressing Her-2 using neratinib, a permanent Her-2 inhibitor, sensitized cellular response to these chemodrugs in cells with CLDN9 knockdown. (4) Conclusions: CLDN9 is an important prognostic indicator for patients with breast cancer and also a pivotal factor in assessing patient responses to chemotherapies. Her-2 is a negating factor for the treatment response prediction value by CLDN9 and negating Her-2 and CLDN9 may enhance breast cancer cellular response to chemotherapeutic drugs

Death associated protein‑3 (DAP3) and DAP3 binding cell death enhancer‑1 (DELE1) in human colorectal cancer, and their impacts on clinical outcome and chemoresistance

Death associated protein‑3 (DAP3) was identified as a responsive protein to interferon‑gamma‑induced cell death which possibly exerts this regulation by interacting with DAP3 binding cell Death enhancer‑1 (DELE1), a newly discovered mitochondrial stress protein in response to cell stress signals. Whilst DAP3 has been shown to be aberrantly expressed in several cancer types (i.e. breast cancer), little is known about the relationship between DAP3 and DELE1 in cancers. The present study examined the expression levels of both DAP3 and DELE1 in clinical colorectal cancers (CRCs), as well as their implication on chemoresistance and mechanism behind the action. Firstly, transcript levels of both DAP3 and DELE1 were quantitatively assessed in a clinical cohort of CRC (n=94). Tumour tissues had significantly higher levels of DAP3, but not DELE1 compared with normal tissues. Levels of DAP3 and DELE1 had a significant association with patient's clinical outcomes and local recurrence. DAP3 and DELE1 significantly correlated in normal colorectal tissues but not in tumour tissues. Secondly, the protein levels of DAP3 and DELE1 were evaluated in both normal and tumour colon tissues which showed that both proteins were highly aberrant in CRC tissues. In addition, both DAP3 and DELE1 at transcript and protein levels were identified as prognostic factors for patient's clinical outcomes. Furthermore, in in vitro assays, knocking down DAP3 or DELE1, and in particular both DAP3 and DELE1 together rendered the CRC cells more sensitive to chemotherapy drugs, consistent with clinical findings of the TCGA‑COAD datasets. The acquisition of drug sensitivity following the genetic knockdown was independent of the mitochondrial metabolism, as neither DAP3 knockdown nor DELE1 knockdown showed a significant change. In summary, DAP3 and DELE1 are highly aberrant in CRCs, and both molecules are prognostic factors for patient's clinical outcomes and local recurrence, and are indicators for chemoresistance

Metastatic Lymph Node 64 (MLN64) expression in gastric cancer, the clinical and molecular implications in drug resistance

Background/Aim: Metastatic Lymph Node 64 (MLN64) is often co-amplified with ERBB2 (HER2) and plays a role in the progression of breast and prostate cancers. The present study explored the expression of MLN64 in clinical gastric cancer in association with the ERBB family and its impact on drug resistance in patients. Materials and Methods: Two independent gastric cancer cohorts (n=324; n=87) were used to explore the expression profile of MLN64 in con-junction with ERBB family members in clinical gastric cancer and its association with neoad-juvant chemotherapy responses. Gastric cancer AGS and HCG27 cells with MLN64 knock-down were generated to determine the function of MLN64 in cell behavioral changes. Results: Gastric tumor tissues expressed significantly increased levels of MLN64 compared with normal tissues (p<0.01); however, MLN64 alone was a weak prognostic indicator. An integrated co-expression of MLN64, ERBB4, and NRG4 was a significant factor in assessing overall survival in both cohorts. MLN64 was a profound indicator of patient response to neoadjuvant chemotherapy. In vitro studies indicated a significant contribution of MLN64 to the response of gastric cancer cells to chemodrugs and Her-2 inhibitors. MLN64 knockdown also contributed to the adhesiveness and migration and suggested a possible mechanism mediated by the in-teraction between MLN64 and ERBBs. Conclusion: MLN64 is an indicator for patient response to neoadjuvant chemotherapies in gastric cancer. Together with the expression pattern of ERBB4, it makes is a poor prognostic factor in gastric cancer patients

Striatins and the STRIPAK complex partners in the clinical outcome of patients with breast cancer and responses to drug treatment

Objective: Striatins (STRNs) family, which contains three multi-domain scaffolding proteins, are cornerstones of the striatins interacting phosphatase and kinase (STRIPAK) complex. Although the role of the STRIPAK complex in cancer has become recognized in recent years, its clinical significance in breast cancer has not been fully established. Methods: Using a freshly frozen breast cancer tissue cohort containing both cancerous and adjacent normal mammary tissues, we quantitatively evaluated the transcript-level expression of all members within the STRIPAK complex along with some key interacting and regulatory proteins of STRNs. The expression profile of each molecule and the integrated pattern of the complex members were assessed against the clinical-pathological factors of the patients. The Cancer Genome Atlas (TCGA) dataset was used to evaluate the breast cancer patients' response to chemotherapies. Four human breast cancer cell lines, MDA-MB-231, MDA-MB-361, MCF-7, and SK-BR-3, were subsequently adopted for in vitro work. Results: Here we found that high-level expressions of STRIP2, calmodulin, CCM3, MINK1 and SLMAP were respectively associated with shorter overall survival (OS) of patients. Although the similar pattern observed for STRN3, STRN4 and a contrary pattern observed for PPP2CA, PPP2CB and PPPR1A were not significant, the integrated expression profile of STRNs group and PPP2 group members constitutes a highly significant prognostic indicator for OS [P<0.001, hazard ratio (HR)=2.04, 95% confidence interval (95% CI), 1.36-3.07] and disease-free survival (DFS) (P=0.003, HR=1.40, 95% CI, 1.12-1.75). Reduced expression of STRN3 has an influence on the biological functions including adhesiveness and migration. In line with our clinical findings, the breast cancer cells responded to STRN3 knockdown with changes in their chemo-sensitivity, of which the response is also breast cancer subtype dependent. Conclusions: Our results suggest a possible role of the STRIPAK complex in breast cancer development and prognosis. Among the members, the expression profile of STRN3 presents a valuable factor for assessing patients' responses to drug treatment

Epithelial Protein Lost in Neoplasm, EPLIN, the Cellular and Molecular Prospects in Cancers

Epithelial Protein Lost In Neoplasm (EPLIN), also known as LIMA1 (LIM Domain And Actin Binding 1), was first discovered as a protein differentially expressed in normal and cancerous cell lines. It is now known to be key to the progression and metastasis of certain solid tumours. Despite a slow pace in understanding the biological role in cells and body systems, as well as its clinical implications in the early years since its discovery, recent years have witnessed a rapid progress in understanding the mechanisms of this protein in cells, diseases and indeed the body. EPLIN has drawn more attention over the past few years with its roles expanding from cell migration and cytoskeletal dynamics, to cell cycle, gene regulation, angiogenesis/lymphangiogenesis and lipid metabolism. This concise review summarises and discusses the recent progress in understanding EPLIN in biological processes and its implications in cancer