[Manual immunohistochemistry for detecting ALK gene fusion antibody in 519 cases of non-small lung cancer].

OBJECTIVE: To investigate the expression of anaplastic lymphoma kinase (ALK) gene fusion antibody in non-small cell lung cancer (NSCLC) and explore the clinicopathological significance. METHODS: Using manual immunohistochemistry (IHC) with D5F3 rabbit monoclonal antibody, we detected the expression of ALK gene fusion protein in 519 cases of NSCLC. The relations of ALK fusion protein with the clinical characteristics of the patients and the histological classification of the tumors were analyzed. The expressions of ALK fusion protein were compared between surgical specimens and biopsy samples, and the consistency of manual IHC results was evaluated with the results of a fully automated IHC instrument and fluorescence in situ hybridization (FISH). RESULTS: The positivity rate of ALK fusion protein was 11.37% (59/519) among the cases detected by manual IHC. The patients tended to have a young age of onset (P=0.048) and most of the tumors were adenocarcinoma. In the surgical specimens, ALK fusion protein was expressed mostly in invasive mucinous adenocarcinoma (P<0.01), and it was a high risk factor of lymph node metastasis [OR=2.188(95%C.I:1.161-4.122)]. No statistical difference was found in the test results of manual IHC between surgical specimens and biopsy samples. The results by manual IHC suggesting a strong expression were consistent with the results by automated IHC and FISH. CONCLUSION: Manual IHC can be reliable for screening ALK fusion arrangement in patients with NSCLC.

Expression of paired basic amino acid-cleaving enzyme 4 (PACE4) correlated with prognosis in non-small cell lung cancer (NSCLC) patients.

BACKGROUND: Paired basic amino acid-cleaving enzyme 4 (PACE4) was shown to enhance tumor cells proliferation and invasive. This study provides the first investigation of PACE4 expression in non-small cell lung cancer (NSCLC) and the correlation with clinicopathologic features, prognostic indicators of 172 cases. METHODS: Quantitative real-time PCR (RT-PCR) and immunofluorescence (IF) were applied to detect PACE4 expression in NSCLC and 16HBE cell lines, then 172 consecutive NSCLC and 15 normal lung tissues were studied through immunohistochemistry (IHC). The association between PACE4 expression and clinicopathological parameters was evaluated. Kaplan-Meier survival analysis and Cox proportional hazards models were used to estimate the effect of PACE4 expression on survival. RESULTS: PACE4 expression in NSCLC were significantly higher than normal lung cell and tissues (P<0.05). PACE4 had cytoplasmic expression and was observed in 111 of the 172 (64.5%) NSCLC patients. Clinicopathologically, PACE4 expression was significantly associated with lymph node metastasis (N stage) (P=0.007), and clinical stage (P=0.024). Multivariable analysis confirmed that PACE4 expression increased the hazard of death after adjusting for other clinicopathological factors [hazards ratio (HR): 1.584; 95% confidence interval (CI): 1.167-2.151; P<0.001]. Overall survival (OS) was significantly prolonged in PACE4 negative group when compared with PACE4 positive group (5-year survival rates, 23.1% vs. 54.5%, log-rank test, χ(2)=17.717, P<0.001), as was disease-free survival (DFS) (5-year survival rates, 23.4% vs. 55.4%, log-rank test, χ(2)=20.486, P<0.001). CONCLUSIONS: Our results suggest that positive expression of PACE4 is an independent factor for NSCLC patients and it might serve as a potential prognostic biomarker for patients with NSCLC.

CLIC4, ERp29, and Smac/DIABLO derived from metastatic cancer stem-like cells stratify prognostic risks of colorectal cancer.

PURPOSE: Cancer stem-like cells have been well accepted to be involved in recurrence and metastasis of cancers, but the prognostic potential of biomarkers integrating with metastasis and cancer stem-like cells for colorectal cancer is unclear. EXPERIMENTAL DESIGN: We identified three proteins, CLIC4, ERp29, and Smac/DIABLO, from metastatic cancer stem-like cells of colorectal cancer and verified the proteins' role in metastatic behaviors. The proteins were detected by IHC in colorectal cancer tumors and matched colonic mucosa from patients with colorectal cancer who underwent radical surgery in the training cohort. The associations between proteins expression levels and five-year disease-specific survival (DSS) were evaluated to predict the survival probability in the training cohort of 421 cases and the validation cohort of 228 cases. RESULTS: A three-protein panel including CLIC4, ERp29, and Smac/DIABLO, which was generated from multivariate analysis by excluding clinicopathologic characteristics from the training cohort, distinguished patients with colorectal cancer into very low-, low-, middle-, and high-risk groups with significant differences in five-year DSS probability (88.6%, 63.3%, 30.4%, 11.4%; P < 0.001). The panel is independent from tumor-node-metastasis staging system and histologic grading to predict prognosis, and also enables classification of validation cohort into four risk stratifications (five-year DSS probability is 98.2%, 80.2%, 25.6%, and 2.7%; P < 0.001). CONCLUSIONS: CLIC4, ERp29, and Smac/DIABLO integrated into a novel panel based on cancer stem-like cells in association with metastasis stratify the prognostic risks of colorectal cancer. Prediction of risks with molecular markers will benefit clinicians to make decisions of individual management with postoperative colorectal cancer patients.

Stathmin, a new target of PRL-3 identified by proteomic methods, plays a key role in progression and metastasis of colorectal cancer.

To better understand the role of PRL-3 in progression and metastasis of colorectal cancer (CRC), we searched for PRL-3 associated proteins using proteomic methods. We identified 39 PRL-3 associated proteins based on proteomic strategy. Stathmin, a key oncoprotein, was proved to be a new PRL-3 associated protein. Notably, co-immunoprecipitation assays in both endogenous CRC cell lines and CRC tissues indicated that PRL-3 could interact with stathmin. And, both stathmin and PRL-3 contributed to microtubule (MT) destabilization of CRC cells. Moreover, gain-of-function and loss-of-function analyses revealed that stathmin promoted proliferation, cell adhesion, and migration of human CRC cells. Immunohistochemical analysis of 149 colorectal tumor samples showed that overexpression of stathmin was strongly correlated with tumor differentiation (P = 0.035), tumor invasion (P = 0.024), lymph node status (P < 0.001), Dukes classification (P < 0.001), and TNM staging (P < 0.001) of CRC patients. Univariate and multivariate survival analyses further supported that overexpression of stathmin protein was a potential independent poor prognostic factor for CRC. Our results reveal many PRL-3 associated proteins for the first time. The oncoprotein stathmin plays a key role in CRC as a new target of PRL-3. Interaction between PRL-3 and stathmin leads to MT destabilization of CRC cells, which contributes to progression and metastasis of CRC.

A five-gene signature as a potential predictor of metastasis and survival in colorectal cancer.

To understand the molecular mechanisms of metastasis and prognosis of colorectal cancer (CRC), we isolated single cell-derived progenies (SCPs) from SW480 cells in vitro and compared their metastatic potential in an orthotopic CRC tumour model in vivo. Two groups of SCPs with the capability of high and low metastasis, respectively, were obtained. By analysing the gene expression profiles of high (SCP51), low (SCP58) metastatic SCPs, and their parental cell line (SW480/EGFP), we demonstrated that 143 genes were differentially expressed either between SCP51 and SCP58 or between SCP58 and SW480/EGFP. Gene-annotation enrichment analysis of DAVID revealed 80 genes in the top ten clusters of the analysis (gene enrichment score > 1). Of the 80-gene set, 32 genes are potentially involved in metastasis, as revealed by Geneclip. Five putative metastatic genes (LYN, SDCBP, MAP4K4, DKK1, and MID1) were selected for further validations. Immunohistochemical analysis in a cohort of 181 CRC clinical samples showed that the individual expression of LYN, MAP4K4, and MID1, as well as the five-gene signature, was closely correlated with lymph node metastasis in CRC patients. More importantly, the individual expression of LYN, MAP4K4, SDCBP, and MID1, as well as the five-gene signature, was significantly correlated with overall survival in CRC patients. Thus, our five-gene signature may be able to predict metastasis and survival of CRC in the clinic, and opens new perspectives on the biology of CRC.