Longzhen Piao

Lentivirus-mediated carboxyl-terminal modulator protein gene transfection via aerosol in lungs of K-ras null mice

The low efficiency of conventional therapies in achieving long-term survival of lung cancer patients calls for development of novel options. Aerosol gene delivery may provide the alternative for safe and effective treatment for lung cancer. Therefore, current study was performed to elucidate the potential effects of C-terminal modulator protein (CTMP) via aerosol on lung tumorigenesis. Lentiviral vector-CTMP was delivered into K-ras null lung cancer mice through the nose-only inhalation system for 30u2009min. After 48u2009h, the potential effects of CTMP on Akt1-related signals and cell cycle regulation in the lungs were evaluated by western blot, immunohistochemistry and zymography. Lentivirus-based CTMP delivery inhibited the Akt1 activity through selective suppression of Akt1 phosphorylation at Ser473. Aerosol delivery of CTMP inhibited proteins important for Akt1 signals, cell cycle and tumor metastasis in lungs of K-ras null mice. Together, our results suggest that lentivirus-mediated aerosol delivery of CTMP may be compatible with noninvasive in vivo gene therapy. Our results emphasize the importance of noninvasive-targeted delivery of CTMP for lung cancer therapy in the future. While the studies are conducted in mice, it is envisioned that noninvasive targeting the specific genes responsible for cancer progression is an attractive strategy for effective anticancer therapeutics.

Suppression of Lung Tumorigenesis by Leucine Zipper/ EF Hand-Containing Transmembrane-1

Background Leucine zipper/EF hand-containing transmembrane-1 (LETM1) encodes for the human homologue of yeast Mdm38p, which is a mitochondria-shaping protein of unclear function. However, a previous study demonstrated that LETM1 served as an anchor protein for complex formation between mitochondria and ribosome, and regulated mitochondrial biogenesis. Methodology/Principal Findings Therefore, we examine the possibility that LETM1 may function to regulate mitochondria and lung tumor growth. In this study, we addressed this question by studying in the effect of adenovirus-mediated LETM1 in the lung cancer cell and lung cancer model mice. To investigate the effects of adenovirus-LETM1 in vitro, we infected with adenovirus-LETM1 in A549 cells. Additionally, in vivo effects of LETM1 were evaluated on K-ras LA1 mice, human non-small cell lung cancer model mice, by delivering the LETM1 via aerosol through nose-only inhalation system. The effects of LETM1 on lung cancer growth and AMPK related signals were evaluated. Adenovirus-mediated overexpression of LETM1 could induce destruction of mitochondria of lung cancer cells through depleting ATP and AMPK activation. Furthermore, adenoviral-LETM1 also altered Akt signaling and inhibited the cell cycle while facilitating apoptosis. Theses results demonstrated that adenovirus-LETM1 suppressed lung cancer cell growth in vitro and in vivo. Conclusions/Significance Adenovirus-mediated LETM1 may provide a useful target for designing lung tumor prevention and treatment.

Correlation between HER-2/neu(erbB-2) expression level and therapeutic effect of combination treatment with HERCEPTIN and chemotherapeutic agents in gastric cancer cell lines

IntroductionAlthough advanced gastric cancer has many limitations and response rate is marginal in chemotherapy. Overexpression of human epidermal growth factor receptor 2(HER-2/neu) gene and its protein are associated with increased cell division and a high rate of tumor growth and have been reported in several malignancies. Especially, approximately 30% of breast cancer patients have overexpression of HER-2/neu protein and the overexpression metastasize faster, induces resistance of the chemotherapy and down-regulate function of estrogen receptor. Recombinant humanized anti-HER2 antibody (Herceptin) inhibits proliferation of HER-2/neu overexpressing tumor cells and the use of that in combination in metastatic breast cancer have increased cytotoxicity of chemotherapeutic agents.MethodsWe evaluated the expression of HER-2/neu protein in gastric cell lines by FACS and then comparing the cytotoxicity in chemotherapeutics (doxorubicin, cisplatin, paclitaxel, 5-FU) alone and in combination with Herceptin according to the expression of HER-2/neu protein by MTT assay.Results1. NCI-N87 (88%) gastric cancer cell line and SK-BR-3 (89%) breast cancer cell line with strong positivity of HER-2/neu expression. YBC-2 (55%) and YBC-3 (48%) gastric cancer cell line with intermediated, weak positivity respectively. Negative control U-87 MG (6%) brain cancer cell line were showed low expression of HER-2/neu. 2. Cell growth was dose-dependently inhibited in HER-2/neu positive, control cell line SK-BR-3 by Herceptin treatment but not observed in HER-2/neu negative control cell line U-87 MG. Effective growth inhibition was not observed in gastric cancer cell lines with single treatment of Herceptin, all cell lines observed the dose-dependent growth inhibition to chemotherapeutic agents (doxorubicin, cisplatin, paclitaxel and 5-FU). 3. Combination of Herceptin with doxorubicin observed synergistic effects in all cancer cell lines except YBC-3, combination of Herceptin with cisplatin observed NCI-N87 and SK-BR-3 and combination of Herceptin with paclitaxel observed synergistic effects in YBC-2. Combination of Herceptin with 5-FU observed antagonistic effects in all cancer cell lines.ConclusionsAccording to HER-2/neu expression level, effect of anti-cancer agents was observed differently in combination of Herceptin with chemotherapeutic agents. This suggests that HER-2/neu expression level can be applied standard of combination drug selection in combination of Herceptin With chemotherapeutic agents in gastric cancer.

High expression of leucine zipper-EF-hand containing transmembrane protein 1 predicts poor prognosis in head and neck squamous cell carcinoma.

Leucine zipper-EF-hand containing transmembrane protein 1 (LETM1) is a mitochondrial inner membrane protein and plays an important role in mitochondrial ATP production and biogenesis. High expression levels of LETM1 have been correlated with numerous human malignancies. This study explored the clinicopathological significance of LETM1 expression as a prognostic determinant in head and neck squamous cell carcinoma (HNSCC). HNSCC samples from 176 patients were selected for immunohistochemical staining of LETM1 protein. Correlations between LETM1 overexpression and clinicopathological features of HNSCC were evaluated by Chi-squared tests and Fishers exact tests, and relationships between prognostic factors and patient survival were analyzed using Cox proportional hazards models. Our results demonstrated that the strongly positive rate of LETM1 protein was 65.3% in HNSCC, which was significantly higher than in either adjacent nontumor tissue (25.0%) or normal squamous epithelia (6.7%). LETM1 overexpression correlated with poor differentiation, presence of lymph node metastasis, advanced stage, absence of chemoradiotherapy, and 5-year disease-free survival and overall survival rates in HNSCC. Further analysis showed that high LETM1 expression, advanced stage, and nonchemoradiotherapy were significant independent risk factors for mortality in HNSCC. In conclusion, LETM1 plays an important role in the progression of HNSCC and is an independent poor prognostic factor for HNSCC.

Clinical implication of leucine zipper/EF hand-containing transmembrane-1 overexpression in the prognosis of triple-negative breast cancer

Triple negative breast cancer (TNBC) is a heterogeneous disease with higher rates of relapse and decreased overall survival in metastatic tumors. Due to its poor prognosis, it is necessary to identify effective biomarkers that are associated with tumor growth and metastasis. The leucine zipper/EF hand-containing transmembrane-1 (LETM1) protein, which is a mitochondrial inner membrane protein, can reduce mitochondrial biogenesis and ATP production. The expression levels of LETM1 were significantly increased in numerous human malignancies. However, the clinicopathological characteristics and prognostic value of LETM1 overexpression in TNBC remains unclear. LETM1 protein was detected in 107 TNBC, 42 ductal carcinoma in situ (DCIS) and 65 adjacent non-tumor breast tissues using immunohistochemical (IHC) staining. Immunofluorescence (IF) staining was also performed to detect the localization of LETM1 protein in MCF-7 BC cells. The correlations between LETM1 overexpression and clinicopathological features of TNBC were evaluated using Chi-squared test and Fishers exact tests. The survival rate was calculated using the Kaplan-Meier method. LETM1 protein showed cytoplasmic staining patterns in TNBC. The strongly positive rate of LETM1 in TNBC was 69.2% (74/107), which was significantly higher than in both DCIS 35.7% (15/42) and adjacent non-tumor tissues 12.3% (8/65). High-level expression of LETM1 was positively correlated with late clinical stage, poor differentiation, lymph node metastasis, disease-free survival (DFS) and 10-year overall survival (OS) rates in TNBC. Further analysis showed that high LETM1 expression along with clinical stage emerged as significant independent risk factors in patients with TNBC. In conclusion, LETM1 protein overexpression is associated with TNBC progression, and may be a potential biomarker for poor prognostic evaluation of TNBC.

Identification of differentially expressed genes in gastric cancer by high density cDNA microarray

The identification of molecular markers for diagnosis, treatment, and prognosis is a significant issue in the management of patients with gastric cancer. We compared the expression profiles of 23 gastric cancers and 22 normal gastric tissues using cDNA microarrays. We divided the samples into two sets, 11 pairs as a training set and 12 unpaired gastric cancer and 11 unpaired normal gastric tissues as a test set. We selected significant genes in the training set and validated the significance of the genes in the test set. We obtained 238 classifier genes that showed a maximum cross-validation probability and clear hierarchical clustering pattern in the training set, and showed excellent class prediction probability in the independent test set. The classifier genes consisted of known genes related to the biological features of cancer and 28% unknown genes. We obtained genome-wide molecular signatures of gastric cancer, which provides preliminary exploration data for the pathophysiology of gastric cancer.

Long non-coding RNA activated by TGF-β expression in cancer prognosis: A meta-analysis

BACKGROUNDnRecently, long non-coding RNA activated by transforming growth factor beta (TGF-β) (lncRNA ATB) was shown to be useful in cancer prognosis, however, its prognostic value in human cancer has been inconsistent. Our study aimed to explore the prognostic role of lncRNA ATB expression in cancer prognosis.nnnMETHODSnPubMed, Embase, and Cochrane Library databases were thoroughly searched to retrieve studies focusing on the prognostic role of lncRNA ATB expression in cancer, and meta-analysis was performed.nnnRESULTSnA total of 15 studies were included into this meta-analysis. High lncRNA ATB expression was significantly related to shorter overall survival (OS) (HRu202f=u202f2.44, 95%CIu202f=u202f1.98-3.01, Pu202f<u202f0.01), recurrence-free survival (RFS) (HRu202f=u202f1.85, 95%CIu202f=u202f1.42-2.40, Pu202f<u202f0.01), disease-free survival (DFS) (HRu202f=u202f3.61, 95%CIu202f=u202f2.45-5.33, Pu202f<u202f0.01), and progression-free survival (PFS) (HRu202f=u202f2.97, 95%CIu202f=u202f2.12-4.16, Pu202f<u202f0.01) when compared with low lncRNA ATB expression in cancer. Moreover, Patients with high lncRNA ATB expression tended to have worse tumor differentiation (Pu202f<u202f0.01), more advanced clinical stage (Pu202f<u202f0.01), deeper tumor invasion (Pu202f<u202f0.01), earlier distant metastases (Pu202f=u202f0.02), lymph node metastases (Pu202f=u202f0.04), and vascular invasion (Pu202f<u202f0.01) when compared with those with low lncRNA ATB expression.nnnCONCLUSIONSnHigh lncRNA ATB expression was significantly associated with worse prognosis in cancer. LncRNA ATB expression could be used as a prognostic biomarker for human cancer.

Identification of LETM1 as a marker of cancer stem-like cells and predictor of poor prognosis in esophageal squamous cell carcinoma

Leucine zipper-EF-hand containing transmembrane protein 1 (LETM1) is closely related to the occurrence and development of malignant tumors. This study discusses the expression of LETM1 in esophageal squamous cell carcinoma (ESCC) and its association with cancer stem-like cells (CSC). We used immunohistochemistry in 166 ESCC tissue samples, as well as Western blot and immunofluorescent methods in ESCC cell lines, to study the role of LETM1 and its association with CSC in ESCC. The expression of LETM1 was significantly higher in ESCC, and it was closely related to the primary tumor stage and clinical stage. LETM1 expression was significantly associated with lower overall survival and disease-free survival. In addition, the protein expression of LETM1 and CSC markers was higher in TE11 and ECG10 than in other ESCC cell lines. Moreover, the expression of LETM1 positively correlated with LSD1, CD44, and OCT4. Immunofluorescence revealed that LETM1 costained with CD44 and OCT4 in ECG10. The expression of LETM1 was associated with not only HIF-1α but also higher microvessel density and tumor-associated macrophage infiltration. Furthermore, LETM1 significantly correlated with cyclinD1 and pAkt. High expression of LETM1 indicates poor prognosis and may be a potential CSC marker in ESCC. Moreover, LETM1 may be a novel therapeutic target for the treatment of ESCC.

B7H4 is associated with stemness and cancer progression in esophageal squamous cell carcinoma

B7H4 is overexpressed in human cancers and often correlates with poor clinical outcome. There is a lack of data on the role of B7H4 as a cancer stem cell (CSC) regulator in esophageal squamous cell carcinoma (ESCC) and its expression levels compared to other stemness genes in ESCC. In this study, we have assessed the expression of B7H4 and cancer stemness proteins in 156 paraffin-embedded ESCC tissue samples using immunohistochemistry as well as in ESCC cell lines using Western blotting and immunofluorescence imaging. The correlation of B7H4 expression with clinicopathological parameters, cell cycle regulating genes, and PI3K/Akt/NF-κB signaling genes was investigated. The expression of B7H4 in ESCC tissue was correlated with the primary tumor (pT) stage, stromal activity, and the expression of CD68 and HIF-1α. However, B7H4 expression was negatively associated with CD8+ T cell infiltration in ESCC tissues. Moreover, B7H4 was found to be strongly linked to prognostic factors leading to poor clinical outcome. B7H4-expressing cancer cells also expressed known cancer stemness proteins (Sox9, LSD1, Oct4, and LGR5). Moreover, B7H4, Sox9, LSD1, Oct4, and LGR5 were highly expressed in more poorly differentiated ESCC cell lines. Notably, B7H4 expression was positively associated with the expression of cell cycle regulators such as cyclin D1, p27, and PI3K/Akt/NFκB signaling proteins. B7H4 could be a novel cancer stem cell marker for the prognostic evaluation of ESCC patients as well as a potential therapeutic target against ESCC.