Haiping Pei

Profiling protein markers associated with the sensitivity to concurrent chemoradiotherapy in human cervical carcinoma.

Concurrent chemoradiotherapy (CCRT) is recently recommended as the primary and standard treatment modality for cervical cancer. The aim of this study is to investigate the protein biomarkers associated with CCRT sensitivity, so as to better understand the mechanisms underlying CCRT resistance. Fresh tumor tissues from five cases for each group of CCRT-highly sensitive (CCRT-HS) and CCRT-lowly sensitive (CCRT-LS) were analyzed by 2-D electrophoresis coupled with MALDI-TOF-MS, followed by Western blot for four candidate proteins including S100A9, galectin-7, nuclear matrix protein-238 (NMP-238), and heat shock protein-70 (HSP-70). In randomly selected CCRT-HS (n = 60) and CCRT-LS (n = 35) cases, these four differentially expressed proteins were detected by tissue microarray with immunohistochemistry staining to explore the association between these interested proteins and CCRT sensitivity. Nineteen proteins differentially expressed more than four times between two groups were identified. An association was revealed between CCRT sensitivity and increased S100A9 and galectin-7, but decreased NMP-238 and HSP-70 expression (p < 0.001, respectively). Although none of these four protein markers could be used as an independent predictive factor, a recurrence prediction model was generated by combining S100A9, galectin-7, NMP-238, and HSP-70 as a full predictive factor. The proteomic analysis combined with tissue microarray provides us a dramatic tool in predicting CCRT response. The increased expression of S100A9 and galectin-7, but decreased expression of NMP-238 and HSP-70, suggests a significantly increased sensitivity to CCRT in cervical cancer.

A prognostic analysis of 895 cases of stage III colon cancer in different colon subsites

PurposeStage III colon cancer is currently treated as an entity with a unified therapeutic principle. The aim of the retrospective study is to explore the clinicopathological characteristics and outcomes of site-specific stage III colon cancers and the influences of tumor location on prognosis.MethodsEight hundred ninety-five patients with stage III colon cancer treated with radical operation and subsequent adjuvant chemotherapy (5-fluorouracil/oxaliplatin) were divided into seven groups according to colon segment (cecum, ascending colon, hepatic flexure, transverse colon, splenic flexure, descending colon, and sigmoid colon). Expression of excision repair cross-complementing group 1 (ERCC1) and thymidylate synthase (TS) was examined by immunohistochemistry. We assessed if differences exist in patient characteristics and clinic outcomes between the seven groups.ResultsThere were significant differences in tumor differentiation (P < 0.001), T stage (P < 0.001), N stage (P < 0.001), American Joint Committee on Cancer (AJCC) tumor–node–metastasis (TNM) stage (P < 0.001), metachronous liver metastasis (P < 0.001), metachronous lung metastasis (P < 0.001), and ERCCI expression (P < 0.001) between the seven groups. Both 5-year recurrence-free survival (RFS) and 5-year overall survival (OS) exhibited significant differences (both P < 0.001) with survival gradually decreasing from cecum to sigmoid colon. Cox regression analyses identified that tumor location was an independent prognostic factor for RFS and OS.ConclusionsStage III colon cancer located proximally carried a poorer survival than that located distally. Different efficacies of FOLFOX adjuvant chemotherapy may be an important factor affecting survival of site-specific stage III colon cancers.

Roles of galectin-7 and S100A9 in cervical squamous carcinoma: Clinicopathological and in vitro evidence.

In our study, we for the first time assessed the association of galectin‐7 and S100A9 with clinicopathological variables and survival outcomes in cervical squamous carcinoma patients and explored the underlying molecular mechanisms in cervical squamous carcinoma cell lines. Immunohistochemical analysis of 243 patient samples showed that the positive staining rate for galectin‐7 and S100A9 gradually decreased from normal cervical tissue to intraepithelial neoplasia and to cervical squamous carcinoma. Both galectin‐7 and S100A9 showed significant negative association with lymph node metastasis and staging of cervical squamous carcinoma. Cervical squamous carcinoma patients with negative staining of galectin‐7 or S100A9 showed significantly lower 5‐year overall survival rate than those with positive staining. Multivariate analysis with the Coxs proportional hazards model indicated that both galectin‐7 and S100A9 had significant protective effect on cervical squamous carcinoma patients. Subsequent in vitro study in SiHa and C‐33A human cervical squamous carcinoma cell lines revealed that knocking down galectin‐7 or S100A9 enhanced tumor cell invasion and tumor cell viability against paclitaxel‐induced apoptotic stress, likely through increasing the matrix metalloproteinase‐9 expression and activating the phosphatidylinositol 3‐kinase/Akt signaling pathway, respectively. Knocking down both galectin‐7 and S100A9 produced a synergistic effect, with galectin‐7 displaying more significant and consistent protective effects than S100A9 on cervical squamous carcinoma cells. In summary, our study for the first time provides clinicopathological and in vitro evidence showing that both galectin‐7 and S100A9 play important protective roles in cervical squamous carcinoma, which provides fresh insights into the biology of cervical squamous carcinoma.

Neuron navigator 2 overexpression indicates poor prognosis of colorectal cancer and promotes invasion through the SSH1L/cofilin-1 pathway.

BackgroundNeuron navigator 2 (NAV2) encodes a member of the neuron navigator gene family, which plays a role in tumorigenesis and cell migration. However, the prognostic value of NAV2 expression in colorectal cancer (CRC) patients and the potential pathway through which NAV2 promotes migration and invasion in CRC cell lines is poorly understood.MethodsThe expression level of NAV2 was detected in CRC tissues from two different CRC cohorts by immunohistochemistry, qRT-PCR and Western blotting; the correlation between NAV2 expression and clinicopathological characters was analyzed, and the prognostic value of NAV2 expression was analyzed using a Cox regression model. CRC cell lines with NAV2 knocked out were used to validate the function and potential pathway used by NAV2 to promote CRC cell migration and invasion.ResultsThe results showed that NAV2 was overexpressed in CRC tissues, and it was closely correlated with depth of invasion, and lymph and distant metastasis. Multivariate analysis indicated that high NAV2 expression was a poor prognostic indicator of recurrence-free survival and overall survival in CRC patients. Furthermore, Cox regression analysis revealed that high NAV2 expression integrated with high tumor budding grade was a powerful independent predictive factor of CRC clinical outcome. In vitro and in vivo assays demonstrated that knockdown of NAV2 led to reduced migration and invasion of cancer cells, and the process involved the regulation of F-actin polymerization through the SSH1L/cofilin-1 pathway.ConclusionBased on these findings, NAV2 could serve as both a prognostic biomarker and a potential therapeutic target for patients with NAV2-positive CRC.

(-)-Epigallocatechin-3-Gallate Inhibits Arsenic-Induced Inflammation and Apoptosis through Suppression of Oxidative Stress in Mice

Background/Aims: Exposure to arsenic in individuals has been found to be associated with various health-related problems including skin lesions, cancer, and cardiovascular and immunological disorders. (-)-Epigallocatechin-3-gallate (EGCG), the main and active polyphenolic catechin present in green tea, has shown potent antioxidant, anti-apoptotic and anti-inflammatory activity in vivo and in vitro. Thus, the present study was conducted to investigate the protective effects of EGCG against arsenic-induced inflammation and immunotoxicity in mice. Methods: Serum IL-1β, IL-6 and TNF-α were determined by ELISA, tissue catalase (CAT), malonyldialdehyde (MDA), superoxide dismutase (SOD), glutathione (GSH), nitric oxide and caspase 3 by commercial kits, mitochondrial membrane potential with Rh 123, mitochondrial ROS with 2’,7’-dichlorofluorescin diacetate (DCFH-DA), apoptotic and necrotic cells and T-cell phenotyping with Flow cytometry analysis. Results: The results showed that arsenic treatment significantly increased oxidative stress levels (as indicated by catalase, malonyldialdehyde, superoxide dismutase, glutathione and reactive oxygen species), increased levels of inflammatory cytokines and promoted apoptosis. Arsenic exposure increased the relative frequency of the CD8+(Tc) cell subpopulation (from 2.8 to 18.9%) and decreased the frequency of CD4+(Th) cells (from 5.2 to 2.7%). Arsenic exposure also significantly decreased the frequency of T(CD3) (from 32.5% to 19.2%) and B(CD19) cells (from 55.1 to 32.5%). All of these effects induced by NaAsO2 were attenuated by EGCG. Conclusions: The present in vitro findings indicate that EGCG attenuates not only NaAsO2-induced immunosuppression but also inflammation and apoptosis.

WD40 repeat-containing 62 overexpression as a novel indicator of poor prognosis for human gastric cancer

AIM WD40 repeat-containing 62 (WDR62) is a centrosome-associated gene involved in cell cycling and proliferation. However, the role of WDR62 in human malignancies remains unknown. The present study aimed to identify the role, if any, of WDR62 in the pathogenesis of human gastric cancer (GC). METHODS WDR62 expression in 372 cases of human GC and eight GC cell lines was determined using quantitative reverse transcription-polymerase chain reaction (qRT-PCR), immunohistochemistry and Western blotting. Correlations between WDR62 expression and clinicopathological characteristics, as well as GC prognosis were determined. WDR62 regulation of GC cell proliferation, invasion, migration and cell cycle distribution were studied both in vitro and in vivo. RESULTS WDR62 expression was significantly increased in GC tissues and cell lines and was associated with poor differentiation and prognosis of GC. WDR62 expression was elevated in GC multidrug resistant cells. Suppressing WDR62 significantly decreased cell proliferation and induced G2/M phase arrest of GC cells. Consistently, WDR62 knockdown inhibited gastric carcinogenesis in nude mice. Regulation of Akt/p38-mitogen-activated protein kinase (MAPK)/multidrug resistance gene 1 (MDR1) expression and activation by WDR62 contributed to the chemoresistance of GC cells. WDR62 overexpresses in GC and the suppression of WDR62 inhibits GC cell growth by inducing G2/M cell cycle arrest. CONCLUSION WDR62 may be a novel prognostic marker and a potential chemotherapy target for GC.

Comparative proteomic study for profiling differentially expressed proteins between Chinese left‐ and right‐sided colon cancers

The aim of the present study is to profile differentially expressed protein markers between left‐sided colon cancer (LSCC) and right‐sided colon cancer (RSCC). Fresh tumor tissue samples from LSCC (n = 7) and RSCC (n = 7) groups were analyzed by two‐dimensional electrophoresis coupled with MALDI‐TOF‐MS, followed by Western blotting. In 50 paraffin embedded samples from each group, levels of four differentially expressed proteins (identified by proteomics analysis) were measured by tissue microarray with immunohistochemistry staining to compare the different protein markers between LSCC and RSCC. Sixteen proteins were found to be differentially expressed between LSCC and RSCC. Ten proteins including HSP‐60 and PDIA1 were identified to be highly expressed in LSCC (P < 0.01 or P < 0.05), while the expression of six proteins including EEF1D and HSP‐27 were higher in RSCC (P < 0.01 or P < 0.05). Virtually all of the indentified proteins were involved in cellular energy metabolism, protein folding/unfolding, and/or oxidative stress. Human colon tumors at various locations have different proteomic biomarkers. Differentially expressed proteins associated with energy metabolism, protein folding/unfolding and oxidative stress contribute to different tumorigenesis, tumor progression, and prognosis between left‐ and right‐sided colon cancer. (Cancer Sci 2013; 104: 141–135)

TCF21 functions as a tumor suppressor in colorectal cancer through inactivation of PI3K/AKT signaling

Colorectal cancer (CRC) has become a major public health problem, ranking as the third most common type of cancer. Our previous study has revealed that TCF21 is frequently silenced by promoter hypermethylation in both CRC cell lines and primary CRC, with TCF21 methylation being significantly correlated with lymph node invasion. In this study, we further analyze the expression of TCF21 in CRC tissues and investigate the role of TCF21 in CRC in vitro and in vivo. We also explore the possible pathway regulated by TCF21. We thus demonstrate that decreased levels of TCF21 are associated with the pathological stage, clinical stage and lymph node metastasis, indicating a poor prognosis in CRC patients; overexpression of TCF21 inhibits cell proliferation, migration and invasion in the colorectal cell lines HCT116 and HT29. Furthermore, TCF21 functions as a tumor suppressor probably through inactivation of PI3K/AKT signaling and inhibition of MMPs. Our results suggest that enhancement of TCF21 levels may be a potential strategy to facilitate the prevention and treatment of CRC in the clinic.

STAT1 Inhibits miR‐181a Expression to Suppress Colorectal Cancer Cell Proliferation through PTEN/Akt

Signal transducers and activators of transcription 1 (STAT1) exhibits tumor‐suppressor properties by inhibiting oncogenic pathways and promoting tumor immunosurveillance. MicroRNAs, a group of non‐coding endogenous ones, may regulate gene expression and plays specific roles in tumorigenesis. Recently, miR‐181a has been reported to be associated with poor prognosis of colorectal cancer (CRC). Using human colorectal cancer cell lines, we demonstrated that STAT1 suppresses both LoVo and SW480 cell growth by down‐regulating miR‐181a. STAT1 regulates the expression of miR‐181a through binding to the elements in the miR‐181as promoter region. Further, we revealed that miR‐181a accelerates CRC cell proliferation through phosphatase and tensin homolog on chromosome ten (PTEN). In addition, PTEN protein was upregulated in response to STAT1 overexpression or miR‐181a inhibition, downregulated in response to STAT1 knockdown or miR‐181a overexpression. Without changes on the AKT protein level, p‐AKT was downregulated by STAT1 overexpression or miR‐181a inhibition while upregulated by STAT1 knockdown or miR‐181a overexpression, indicating PTEN/Akt pathway activated in STAT1/miR‐181a regulation of CRC cell proliferation. Taken together, our findings shed new light on the STAT1/miR‐181a/PTEN pathway in colorectal cancer and add new insight regarding the carcinogenesis of colorectal cancer. J. Cell. Biochem. 118: 3435–3443, 2017.

Significance of inflammation-based indices in the prognosis of patients with non-metastatic colorectal cancer

Previous studies demonstrated that several inflammation-based hematological indices are closely related to various malignancies, including colorectal cancer (CRC). In this study, the prognostic value of inflammation-based markers, including a combination index termed coNLR-PDW, comprising the preoperative neutrophil-to-lymphocyte ratio (NLR) and the platelet distribution width (PDW), was evaluated in 206 patients with non-metastatic CRC treated with surgery at a single medical center. The association of patient demographics, blood chemistry, and serum biochemical indices with recurrence-free survival (RFS) and overall survival (OS) were examined through univariate and multivariate analysis. Receiver operating characteristic curve analysis revealed the optimal cut-off values of the NLR and lymphocyte-to-monocyte ratio (LMR) to be, respectively, 2.0 and 3.32 for both RFS and OS. For PDW, cut-off values of 17.25% and 17.35% were defined for RFS and OS, respectively. On univariate analysis, lymph node involvement, stage, presence of intravascular emboli (IVE), carbohydrate antigen 199 (CA199) ≥ 35 kU/L, NLR ≥ 2.0, LMR ≤ 3.32, elevated PDW, a high coNLR-PDW score, high blood glucose, and high neutrophil and lymphocyte percentages correlated with poorer RFS and OS (P < 0.05). On multivariate analysis, lymph node involvement, IVE, CA199, PDW, and coNLR-PDW correlated with both RFS and OS (P < 0.05), while NLR correlated only with OS (P = 0.001). These results highlight the usefulness of the coNLR-PDW index as a prognostic marker of non-metastatic CRC outcome. In clinical practice, its assessment could contribute to establishing more personalized regimes for patients undergoing tumor resection surgery.