Notch1/TAZ axis promotes aerobic glycolysis and immune escape in lung cancer.

Oncogenic signaling pathway reprograms cancer cell metabolism to promote aerobic glycolysis in favor of tumor growth. The ability of cancer cells to evade immunosurveillance and the role of metabolic regulators in T-cell functions suggest that oncogene-induced metabolic reprogramming may be linked to immune escape. Notch1 signaling, dysregulated in lung cancer, is correlated with increased glycolysis. Herein, we demonstrate in lung cancer that Notch1 promotes glycolytic gene expression through functional interaction with histone acetyltransferases p300 and pCAF. Notch1 signaling forms a positive feedback loop with TAZ. Notch1 transcriptional activity was increased in the presence of TAZ and the activation was TEAD1 independent. Notably, aerobic glycolysis was critical for Notch1/TAZ axis modulation of lung cancer growth in vitro and in vivo. Increased level of extracellular lactate via Notch1/TAZ axis inhibited cytotoxic T-cell activity, leading to the invasive characteristic of lung cancer cells. Interaction between Notch1 and TAZ promoted aerobic glycolysis and immune escape in lung cancer. Our findings provide potential therapeutic targets against Notch1 and TAZ and would be important for clinical translation in lung cancer.

[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.

BRCA1 gene exon 11 mutations in Uighur and Han women with early-onset sporadic breast cancer in the northwest region of China.

The prevalence of BRCA1 gene mutations in breast cancer differs between diverse ethnic groups. Relatively little information is known about patterns of BRCA1 mutations in early-onset breast cancer in women of Uighur or Han descent, the major ethnic populations of the Xinjiang region in China. The aim of this study was to identify BRCA1 mutations in Uighur and Han patients with early-onset (age <35 years), and sporadic breast cancer for genetic predisposition to breast cancer. For detection of BRCA1 mutations, we used a polymerase chain reaction single-stranded conformation polymorphism approach, followed by direct DNA sequencing in 22 Uighur and 13 Han women with early-onset sporadic breast cancer, and 32 women with benign breast diseases. The prevalence of BRCA1 mutations in this population was 22.9% (8/35) among early-onset sporadic breast cancer cases. Of these, 31.8% (7/22) of Uighur patients and 7.69% (1/13) of Han patients were found to have BRCA1 mutations. In 7 Uighur patients with BRCA1 mutations, there were 11 unique sequence alterations in the BRCA1 gene, including 4 clearly disease-associated mutations on exon 11 and 3 variants of uncertain clinical significance on exon 11, meanwhile 4 neutral variants on intron 20 or 2. None of the 11 BRCA1 mutations identified have been previously reported in the Breast Cancer Information Core database. These findings reflect the prevalence of BRCA1 mutations in Uighur women with early-onset and sporadic breast cancer, which will allow for provision of appropriate genetic counseling and treatment for Uighur patients in the Xinjiang region.

[Detection and clinical significance of Notch1 methylation in breast cancer and intraductal proliferative breast lesions].

OBJECTIVE: To explore the relevance between the promoter methylation status of Notch1 gene and the invasive ductal carcinoma and ductal hyperplastic lesions of the breast. METHODS: Methylation status of Notch1 gene in human breast invasive ductal carcinoma (IDC, n = 89), ductal carcinoma in situ (DCIS, n = 20), atypical ductal hyperplasia (ADH, n = 11) and usual ductal hyperplasia (UDH, n = 20) were quantitatively evaluated by MALDI-TOF MS. The expression of Notch1 protein was detected by immunohistochemical stain (SP method). RESULTS: Positive expression rates of Notch1 protein in IDC and DCIS were 91.0% (81/89) and 75.0% (15/20), respectively, which were significantly higher than those of ADH (4/11) and UDH (30.0%, 6/20;P < 0.05). Notch1 protein expression was correlated significantly with lymph node metastasis, pathological grades and TNM stages of IDC. The mean methylation levels of Notch1 gene at CpG_3, CpG_4.5 and CpG_8 significantly decreased in IDC group compared with those of DCIS, ADH and UDH groups (P < 0.0083). In breast carcinomas, the mean methylation rates of Notch1 gene at CpG_4.5, CpG_10.11, and CpG_14.15.16 loci in cases with axillary node metastasis were significantly lower than those without axillary node metastasis (P < 0.05); and the methylation rates at CpG_14.15.16 and CpG_18 loci in stage Iwere lower than that in stage II, further lower than that in stage III (P < 0.05); and that in CpG_1.2, CpG_12.13 loci in grade I (highly-differentiated group) were higher than that in grade II (moderate-differentiated group) and grade III (poorly-differentiated group) (P < 0.05); and the methylation rates at CpG_3, CpG_8 and CpG_14.15.16 loci in ER(+) PR(+) HER2(-) group were lower than that in ER(-) PR(-) HER2(+) group (P < 0.05). CONCLUSIONS: There is an overall hypomethylation of Notch1 gene in breast invasive ductal carcinomas with corresponding over-expression of Notch1 protein. This inverse correlation show that the alteration of protein expression result from hypomethylation oncogene Notch1, and this change may have important significance in breast tumorigenesis and the development. Specific hypomethylation at CpG_3, CpG_ 4.5 and CpG_8 loci of Notch1 gene may play a role in the pathogenesis of breast carcinoma, suggesting the progression and/or malignant transformation from benign glandular lesions of the breast.

Neuregulin-1 regulates the expression of Akt, Bcl-2, and Bad signaling after focal cerebral ischemia in rats.

Neuregulin-1 (NRG-1) is a member of the epidermal growth factor family. Our previous study showed that NRG-1 protected neurons from apoptosis following focal cerebral ischemia by the inhibition of caspase-3 and TNF-alpha expression. However, the molecular signaling mechanisms for this action of NRG-1 following cerebral ischemia are not fully understood. Presently, activation of the PI3K/Akt pathway has been implicated as a major contributor to neuronal survival after an ischemic insult. In the present study, we investigated whether NRG-1 modulates the activation of Akt and its downstream targets Bad and Bcl-2 expression after transient focal cerebral ischemia by intraluminal blockade of the middle cerebral artery. Western blot was employed to analyze the change of phosphorylated Akt (p-Akt) expression; reverse transcription and polymerization chain reaction (RT-PCR) were used to measure changes of Bcl-2 mRNA. The level of phosphorylation of Bad (p-Bad) was determined using an enzyme-linked immunosorbent assay (ELISA). Our results showed that recombinant human NRG-1(3.0 ng.kg-1) significantly increased the expression of p-Akt protein, Bcl-2 mRNA, and the level of p-Bad, respectively, whereas administration of LY294002, a specific inhibitor of PI3K, significantly decreased the expression of p-Akt, p-Bad, and Bcl-2 induced by NRG-1 after a 60 min ischemic insult, followed by 24 h of reperfusion. These results indicate that NRG-1 may be involved in regulating the expression of Bcl-2 and p-Bad through the PI3K/Akt pathway after transient focal cerebral ischemia.

[Notch1 mRNA and protein expression in human breast cancer and normal mammary gland tissues].

OBJECTIVE: To explore the Notch1 mRNA and protein expression in human breast cancers and normal mammary tissues, and their relationship with the clinical indicators of breast cancers were analyzed. METHODS: Notch1 gene of human breast invasive ductal carcinoma (IDC) and normal mammary gland tissues were amplified by RT-PCR, and the expression of Notch1 protein was detected by immunohistochemical Streptavidin-Biotin Complex (SP) stain in 60 IDC, 30 ductal carcinoma in situ (DCIS) and 60 normal mammary tissues. RESULTS: Notch1 gene of human IDC and normal mammary tissues both could express in a transcription level; the positive rates of Notch1 protein expression in normal mammary tissues and DCIS were 55% and 70%. Respectively, which did not differ statistically (P > 0.05), while the positive rate in IDC was 90%, significantly higher than that of the normal mammary tissues and DCIS (P < 0.05). The high expression of Notch1 protein in IDC correlate significantly with lymph node metastasis, pathological grades and TNM stages. CONCLUSIONS: Notch1 protein was over expressed in breast IDC. A high Notch1 protein expression is considered associating with the evolution and malignant transformation of the breast tumor. The expression of Notch1 gene maybe impact the effect of on the progression of breast cancers.

[Analysis of the mutation of BRCA1 gene in 70 Uigur women breast cancer patients in Xinjiang].

OBJECTIVE: To analyze the mutations of BRCA1 in breast cancer patients of Uigur women in Xinjiang. METHODS: By using single strand conformation polymorphism (SSCP) and DNA sequencing, BRCA1 mutations were detected in 70 Uigur women breast cancer cases and 32 cases of benign breast diseases and non-tumor tissue next to carcinoma. RESULTS: (1) 12 new loci of BRCA1 gene mutation were detected firstly in 70 Uigur women breast cancer patients. (2)The frequency of BRCA1 mutation in 70 Uigur women breast cancer cases was 12.86% (9/70). The frequency of BRCA1 mutation in Uigur women early onset breast cancer was 31.82% (7/22), which was significantly higher than that in late onset group (2/48, 4.16%) (chi(2) =10.295, P<0.01). (3) There were BRCA1 gene polymorphisms in 9 of 70 Uigur women breast cancer patients. The loci of polymorphisms in 8 of 9 cases were 3232A>G. (4)In the research group two cases of bilateral breast cancer were found with BRCA1 gene mutation. CONCLUSION: The mutation of BRCA1 gene may be related to Uigur women breast cancer and bilateral breast cancer.