Histone methyltransferase SETD1A interacts with notch and promotes notch transactivation to augment ovarian cancer development.

BACKGROUND: High expression of SETD1A, a histone methyltransferase that specifically methylates H3K4, acted as a key oncogene in several human cancers. However, the function and underlying molecular mechanism of SETD1A in ovarian cancer (OV) remain markedly unknown. METHODS: The expression of SETD1A in OV were detected by Western blot and analyzed online, and the prognosis of STED1A in OV were analyzed online. The protein and mRNA levels were determined by Western blot and RT-qPCR. The cell proliferatin, migration and invasion were measured by CCK-8 and transwell assays. The protein interaction was detected by co-IP assay. The interaction between protein and DNA was performed by ChIP assay. The tumor growth in vivo was performed by xenograft tumor model. RESULTS: SETD1A was overexpressed in OV and a predictor of poor prognosis. Overexpression of SETD1A augmented the abilities of cell proliferation, migration, and invasion in MRG1 and OVCAR5 cells. In comparison, SETD1A knockdown suppressed cell growth, migration, and invasion in SKOV3 and Caov3 cells. Specifically, SETD1A enhanced Notch signaling by promoting the expression of Notch target genes, such as Hes1, Hey1, Hey2, and Heyl. Mechanistically, SETD1A interacted with Notch1 and methylated H3K4me3 at Notch1 targets to enhance Notch signaling. In addition, restoration of Notch1 in SETD1A-knockdown OV cells recovered cell proliferation, migration and invasion, which was inhibited by SETD1A knockdown. Furthermore, reduction of SETD1A suppressed tumorigenesis in vivo. CONCLUSION: In conclusion, our results highlighted the key role of SETD1A in OV development and proved that SETD1A promotes OV development by enhancing Notch1 signaling, indicating that SETD1A may be a novel target for OV treatment.

Population-based analysis on predictors for lymph node metastasis in T1 colon cancer.

BACKGROUND: In this study, we aimed to identify independent predictive factors for lymph node metastasis (LNM) in T1 colon cancer. METHODS: Data of 8056 eligible patients were retrospectively collected from the Surveillance, Epidemiology, and End Results (SEER) database during 2004-2012. We performed logistic regression analysis to identify predictive factors for LNM. Both unadjusted and adjusted Cox regression analyses were used to determine the association between LNM and patient survival. Finally, we used competing risks analysis and the cumulative incidence function (CIF) to further confirm the prognostic role of LNM in cancer-specific survival (CSS). RESULTS: The overall risk of LNM in patients with T1 colon cancer was 12.0% (N = 967). Adjusted logistic regression models revealed that mucinous carcinoma [odds ratio (OR) = 2.26, P < 0.001], moderately differentiated (OR 1.74, P < 0.001), poorly differentiated (OR 5.16, P < 0.001), and undifferentiated carcinoma (OR 3.01, P = 0.003); older age (OR 0.66, P < 0.001 for age 65-79 years, OR 0.44, P < 0.001 for age over 80 years); and carcinoma located in the ascending colon (OR 0.77, P = 0.018) and sigmoid colon (OR 1.24, P = 0.014) were independent predictive factors for LNM. Adjusted Cox regression analysis showed that positive lymph node involvement was significantly associated with CSS [hazard ratio (HR) = 3.02, P < 0.001], which was further robustly confirmed using a competing risks model and the CIF. CONCLUSIONS: This population-based study showed that mucinous carcinoma, tumor grade, age, and primary tumor location were independent predictive factors for LNM in T1 colon cancer. The risk of LNM should be carefully evaluated in patients with T1 colon cancer, before clinical management.

Three-dimensional visualization and measurement of myopectineal orifice in non-inguinal hernia patients.

PURPOSE: The myopectineal orifice (MPO) is a weak area at lower part of the anterior abdominal wall that directly determines the mesh size required in inguinal hernia repair. However, MPO data have mainly been acquired from measurements of cadavers or anesthetized patients. Furthermore, there are very few reports on the measurement of the MPO in Chinese patients. The present study aimed to use three-dimensional visualization technology to measure the MPO in live non-anesthetized Chinese patients, and to use this information to indicate the appropriate mesh size required for inguinal hernia repair. METHODS: In this study, we used the parameters of the MPO and the pelvis that were measured in 40 patients with peripheral arterial disease of the lower limb arteries (80 inguinal regions) using Medraw software (Image Medraw Technology Co., Ltd., China). RESULTS: The result showed that the average width and height of the MPO were 5.71 ± 0.99 cm and 4.96 ± 0.69 cm, respectively (5.22 ± 0.77 cm and 5.13 ± 0.63 cm in males, and 6.20 ± 0.95 cm and 4.80 ± 0.71 cm in females). The average projected area of the MPO was 16.06 ± 4.37 cm2 on the left, and 15.61 ± 4.10 cm2 on the right (P > 0.05). CONCLUSION: Three-dimensional visualization was used to measure the area, width, and height of the MPO in living non-anesthetized Chinese patients. MPO area was correlated with age, but not with pelvic parameters.

TCF7L1 indicates prognosis and promotes proliferation through activation of Keap1/NRF2 in gastric cancer.

Gastric cancer is one of the most common cancers worldwide and is the third leading cause of cancer-related deaths globally. Although significant progress has been made in the diagnosis and treatment for the cancer, less improvement has been made in overall survival rate. Thus, there is an urgent need for a better understanding of the biological aspects of the cancer. The transcription factor transcription factor 7-like 1 (TCF7L1) is an embryonic stem cell signature gene that is upregulated in multiple aggressive cancer types, but its role in gastric cancer has seldom been discussed. In the present study, by using the Cancer Genome Atlas dataset analysis, we demonstrated that patients with higher expression of TCF7L1 could be used to reflect prognosis. An examination of the mechanisms demonstrated that TCF7L1 could positively regulate antioxidant response in gastric cancer cells by positively regulating Keap1/NRF2 [Kelch-like ECH-associated protein 1/nuclear factor (erythroid-derived 2)-like 2] pathway. Collectively, our data demonstrated that TCF7L1 is a novel marker for predicting overall survival of gastric cancer and provided the possible underlying molecular mechanism.

Autophagy Facilitates Metadherin-Induced Chemotherapy Resistance Through the AMPK/ATG5 Pathway in Gastric Cancer.

BACKGROUND/AIMS: Metadherin (MTDH) is overexpressed in some malignancies and enhances drug resistance; however, its role in gastric cancer (GC) and the underlying mechanisms remain largely unexplored. Here, we explore the mechanism by which MTDH induces drug resistance in GC. METHODS: We analysed the level of MTDH in GC and adjacent normal gastric mucosal tissues by real-time quantitative PCR (q-PCR). We also analysed the level of autophagy by western blot analysis, confocal microscopy, and transmission electron microscopy after MTDH knockdown and overexpression, and examined fluorouracil (5-FU) resistance by Cell Counting Kit-8 at the same time. Finally, GC patient-derived xenograft tumours were used to demonstrate 5-FU resistance. An AMPK pathway inhibitor was applied to determine the molecular mechanisms of autophagy. RESULTS: MTDH expression was significantly increased in the GC specimens compared with that in the adjacent normal gastric mucosal tissues. Further study showed a positive correlation between the expression level of MTDH and 5-FU resistance. MTDH overexpression in MKN45 cells increased the levels of P-glycoprotein (P-gp) and promoted 5-FU resistance, while inhibition of MTDH showed the opposite result. The simultaneous inhibition of autophagy and overexpression of MTDH decreased the levels of P-gp and inhibited 5-FU resistance. Moreover, MTDH induced AMPK phosphorylation, regulated ATG5 expression, and finally influenced autophagy, suggesting that MTDH may activate autophagy via the AMPK/ATG5 signalling pathway. Our findings reveal a unique mechanism by which MTDH promotes GC chemoresistance and show that MTDH is a potential target for improved chemotherapeutic sensitivity and GC patient survival. CONCLUSIONS: MTDH-stimulated cancer resistance to 5-FU may be mediated through autophagy activated by the AMPK/ATG5 pathway in GC.

Bone marrow-derived mesenchymal stem cells increase drug resistance in CD133-expressing gastric cancer cells by regulating the PI3K/AKT pathway.

Bone marrow-derived mesenchymal stem cells (BM-MSCs) are recruited to primary tumours to compose the tumour microenvironment. In various cancers, CD133-positive cells have been shown to possess cancer stem cell properties that confer chemoresistance. This study aimed to investigate the role of BM-MSCs in the anti-tumour drug resistance of CD133-expressing gastric cancer cells and explore the underlying mechanisms that governing this role. We found that CD133+ gastric cancer cells displayed more resistance to chemotherapeutics than CD133- cells. In addition, BM-MSCs increased the anti-apoptotic abilities and chemoresistance of CD133+ cells via upregulation of Bcl-2 and downregulation of BAX. Mechanistically, BM-MSCs triggered activation of the PI3K/Akt signalling cascade in CD133+ cells. Blocking the PI3K/Akt pathway inhibited the promotion of chemoresistance. Furthermore, BM-MSCs enhanced the drug resistance of CD133-overexpressing cells in vitro and in vivo, but not that of CD133-knockdown cells, which demonstrated the contribution of CD133 to this process. In conclusion, we demonstrated that BM-MSCs increased the anti-apoptotic abilities and drug resistance of CD133-expressing cells via activation of the PI3K/Akt pathway following Bcl-2 upregulation and BAX downregulation, in which CD133 played a significant role. Targeting this route may help improve the efficacy of chemotherapy in gastric cancer.

Study on lymph node metastasis correlated to lymphangiogenesis, lymphatic vessel invasion, and lymph node micrometastasis in gastric cancer.

BACKGROUND: This study aimed to evaluate the clinical significance of lymphangiogenesis, lymph vessel invasion (LVI), and lymph node (LN) micrometastasis (LNMM) in patients with gastric cancer. METHODS: The influences of the expression levels of LVI, lymph vessel density (LVD) by D2-40 immunohistochemical (IHC) staining (n=68), LNMM (including CK 20 and CK pan immunostainings, n=51) on the clinicopathologic profiles and the prognosis were analyzed. RESULTS: The higher positive rate of LVI-IHC was related to deeper invasion (P=0.044), later TNM stage (P=0.003), and more extensive LN metastasis (LNM, P=0.000). The level of LVD was significantly associated with venous invasion (P=0.037), later TNM stage (P=0.020), positive LVI-HE (P=0.040), positive LVI-IHC status (P=0.001), and severer LNM (P=0.001). Better prognosis in LVI negative group than LVI positive group has been identified. The survival rate of the group with LVD≥15/field was significantly lower than that in the group with LVD≤14/field (P=0.032). Invasion depth, N stage, LNM, blood vessel invasion, or LVI was respectively an independent prognostic factor to 3-y survival rate. The incidence of patients with LNM and metastasized LNs increased respectively from 74.5% (38/51) by HE staining to 88.2% (45/51) by CK immunostaining and from 32.0% (253/791) to 41.5% (328/791) (P=0.001). The increment of LNMM was correlated to larger tumor diameter (P=0.001), deeper invasion (P=0.018), LNM (P=0.001) and later TNM stage (P=0.012), positive LVI (P=0.04). Meanwhile, the evaluation on LNMM revealed the migration of LN stage (N(0)→N(1) in seven patients, N(1)→N(2) in six patients, and N(2)→N(3) in one patient), and TNM stage (I(b)→II in four patients, II→III(a) in 4 patients, III(a)→III(b) in 3 patients, and III(b)→IV in one patient). Survival analysis demonstrated that better prognosis in patients without LNM and/or LNMM. CONCLUSION: Our immunohistochemical analyses using antibodies of D2-40 and CK, including both CK 20 and CK pan, detected a higher incidence of LVIs and LNMs in gastric cancer specimens. This study shows close correlations among lymphangiogenesis related factors, such as LVI, LVD, and LNMM, and patients' prognosis after surgery. Therefore, immunohistochemical evaluations of these factors could be used for the accurate determination of tumor aggressiveness.

Surgical treatment strategy for locally advanced colorectal cancer with abdominal wall invasion.

BACKGROUND: The incidence of abdominal wall metastasis from colorectal cancer (CRC) is very low, but it has a poor prognosis. Despite the advances in radiotherapy, chemotherapy, and targeted therapy, patient prognosis has not improved significantly. Through surgical treatment, some patients with locally advanced CRC with abdominal wall invasion can achieve tumor-free survival or an improved quality of life. METHODS: The clinical data of 15 patients in our department from January 2015 to January 2020 were retrospectively analyzed. All patients underwent preoperative three-dimensional reconstruction of the tumor and abdominal wall after discussion with a multidisciplinary team (MDT). Patient information, including tumor size, defect size, operation time, intraoperative bleeding, hospital stay, and other factors, was collected. RESULTS: All 15 patients underwent resection followed by reconstruction for locally advanced CRC with abdominal wall invasion. The average tumor area and abdominal wall defects were 98.13±71.70 and 270.07±101.95 cm2, respectively; and accurate abdominal wall classification and zoning were obtained for all patients. The average operation time was 431.7±189.2 min, and the average blood loss was 513.3±244.6 mL. The recurrence rates in the incisional hernia and abdominal wall were 6.0% and 13.3%, respectively. The patient survival rate was 87.7%. CONCLUSIONS: Surgical treatment of locally advanced CRC with abdominal wall invasion is feasible, but requires accurate and comprehensive preoperative evaluation.

Application of 3D Visualization Technology in Complex Abdominal Wall Defects.

PURPOSE: To explore the value of medical three-dimensional visualization technology in precise preoperative assessment of complex abdominal wall defects. METHODS: The clinical data of 30 patients were analyzed retrospectively from November 2017 to December 2020 in our department. Ten patients had abdominal wall hernias and 20 patients suffered from abdominal wall tumors. CT examination was performed, and data were stored in the form of DICOM. Three-dimensional reconstruction and related data analysis were performed by Medraw software, which can accurately show the calculation of the abdominal wall defect area, abdominal wall defect classification and zoning. RESULTS: The ratio of the volume of the hernia sac to the whole abdominal volume in 10 patients with abdominal wall hernia was 4.75%. The average ratio of defect area to the whole abdominal wall in 16 patients suffered from abdominal wall tumors was 17.68%. Preoperative three-dimensional reconstruction can accurately obtain an average abdominal wall defect area of 227.83 ± 157.33 cm2 and accurate abdominal wall classification and zoning. Combined with clinical information, we can develop personalized surgical plans for patients. The average operating time was 5.39 ± 2.71 h, respectively, and the average hospital stay was 22.77 ± 11.59 days. The mean follow-up time was 21.09 ± 9.72 months. The incidence of postoperative complications was 23.33% (7/30). The recurrence rates of incisional hernias and abdominal wall tumors were 20.00% (2/10) and 15.00% (3/20), respectively. The patient survival rate was 86.67% (26/30). CONCLUSION: Three-dimensional visualization technology can be used for the accurate evaluation of patients with complex abdominal defects before surgery and can help surgeons design personalized surgical plans for patients.

Histone Methyltransferase SETD1A Induces Epithelial-Mesenchymal Transition to Promote Invasion and Metastasis Through Epigenetic Reprogramming of Snail in Gastric Cancer.

Aberrant epigenetic modification induces oncogene expression and promotes cancer development. The histone lysine methyltransferase SETD1A, which specifically methylates histone 3 lysine 4 (H3K4), is involved in tumor growth and metastasis, and its ectopic expression has been detected in aggressive malignancies. Our previous study reported that SETD1A promotes gastric cancer (GC) proliferation and tumorigenesis. However, the function and molecular mechanisms of SETD1A in GC metastasis remain to be elucidated. In this study, we found that overexpression of SETD1A promoted GC migration and invasion, whereas knockdown of SETD1A suppressed GC migration and invasion in vitro. Moreover, knockdown of SETD1A suppressed GC epithelial-mesenchymal transition (EMT) by increasing the expression of epithelial marker E-cadherin and decreasing the expression of mesenchymal markers, including N-cadherin, Fibronectin, Vimentin, and α-smooth muscle actin (α-SMA). Mechanistically, knockdown of SETD1A reduced the EMT key transcriptional factor snail expression. SETD1A was recruited to the promoter of snail, where SETD1A could methylate H3K4. However, knockdown of SETD1A decreased the methylation of H3K4 on the snail promoter. Furthermore, SETD1A could be a coactivator of snail to induce EMT gene expression. Rescue of snail restored SETD1A knockdown-induced GC migration and invasion inhibition. In addition, knockdown of SETD1A suppressed GC metastasis in vivo. In summary, our data revealed that SETD1A mediated the EMT process and induced metastasis through epigenetic reprogramming of snail.

SETD1A augments sorafenib primary resistance via activating YAP in hepatocellular carcinoma.

AIMS: Sorafenib, the approved first-line chemotherapy drug for HCC (Hepatocellular Carcinoma), remains the key treatment agent which effectively improves the survival rate of advanced HCC patients. However, the sorafenib primary resistance limits the application of sorafenib for HCC treatment. The aims of current study are to explore the role and mechanism of SETD1A (Histone Lysine Methyltransferase SET Domain Containing 1A) in sorafenib primary resistance. MAIN METHODS: The SETD1A expression in HCC was analyzed by Gene Expression Profiling Interactive Analysis. The survival of HCC patients was analyzed by Kaplan-Meier Plotter. Western Blot and Real-time qPCR were performed to measure the protein and mRNA levels, respectively. Cell counting kit-8 assay and colony formation assay were performed to determine cell viability and proliferation. Propidium Iodide and Trypan Blue staining assays were performed to investigate cell death. KEY FINDINGS: Here, we showed that the expression of SETD1A was markedly upregulated in both HCC cell lines and tumor tissues compared to normal hepatocytes and corresponding non-tumor liver tissues, respectively. Regardless of whether treated with sorafenib, the patients who had higher level of SETD1A underwent lower survival rate of overall. In addition, SETD1A expression was positively correlated with the IC50 of sorafenib treated HCC cell lines. Furthermore, we indicated that knockdown of SETD1 augmented proliferation inhibition and cell death induced by sorafenib. SETD1A deficiency impaired YAP (Yes-associated protein) phosphorylation and activation. YAP activation contributed to SETD1A mediated sorafenib primary resistance. SIGNIFICANCE: The current study demonstrated that SETD1A enhanced YAP activation to induce sorafenib primary resistance in HCC.

Histone methyltransferase SETD1A interacts with HIF1α to enhance glycolysis and promote cancer progression in gastric cancer.

Growing tumors alter their metabolic profiles to support the increased cell proliferation. SETD1A, a histone lysine methyltransferase which specifically methylates H3K4, plays important roles in both normal cell and cancer cell functions. However, the function of SETD1A in gastric cancer (GC) progression and its role in GC metabolic reprogramming are still largely unknown. In the current study, we discovered that the expression of SETD1A was higher in GC tumor specimens compared to surrounding nontumor tissues. Upregulation of SETD1A increased GC cell proliferation, whereas downregulation of SETD1A inhibited GC cell proliferation. Furthermore, knockdown of SETD1A reduced glucose uptake and production of lactate and suppressed glycolysis by decreasing the expression of glycolytic genes, including GLUT1, HK2, PFK2, PKM2, LDHA, and MCT4. Mechanistically, SETD1A interacted with HIF1α to strengthen its transactivation, indicating that SETD1A promotes glycolysis through coactivation of HIF1α. SETD1A and HIF1α were recruited to the promoter of HK2 and PFK2, where SETD1A could methylate H3K4. However, knockdown of SETD1A decreased the methylation of H3K4 on HK2 and PFK2 promoter and reduced HIF1α recruitment necessary to promote transcription of glycolytic genes. Inhibition of HIF1α decelerated SETD1A-enhanced GC cell growth. In additional, there was a linear correlation between SETD1A and several key glycolytic genes in human GC specimens obtained from TCGA dataset. Thus, our results demonstrated that SETD1A interacted with HIF1α to promote glycolysis and accelerate GC progression, implicating that SETD1A may be a potential molecular target for GC treatment.

Reduction of Hip2 suppresses gastric cancer cell proliferation, migration, invasion and tumorigenesis.

BACKGROUND: Hip2, a ubiquitin-conjugating enzyme, has been shown to modulate the stability of cyclin B1, a cell cycle regulator. However, the function of Hip2 in gastric cancer (GC) remains largely elusive. METHODS: The expression of Hip2 in GC cell lines was analyzed by RT-qPCR, Western Blotting and Immunohistochemical Staining. shRNA was utilized to knock down the expression of Hip2. Cell growth, cell cycle, migration, invasion and tumorigenesis were performed by CCK-8, BrdU staining, flow cytometry, wound healing, transwell migration and invasion, and xenograft assay, respectively. RESULTS: Hip2 was highly expressed in GC cell lines and patients. High level of Hip2 indicated poor prognosis. Knockdown of Hip2 suppressed cell growth, lead to G2/M phase arrest, and reduced cell migration and invasion in vitro. Furthermore, downregulation of Hip2 inhibited tumorigenesis in vivo. CONCLUSIONS: Elevated expression of HIP2 in GC patients suggested poor prognosis. Reduction of Hip2 suppressed GC progression, indicating that Hip2 may be a potential target for the management of GC.

AAED1 modulates proliferation and glycolysis in gastric cancer.

Gastric cancer is one of the most common and lethal malignancies globally, especially in East Asia. Although significant progress has been made in the diagnosis and treatment of the disease, the overall survival rate remains unchanged at 20­25%. Thus, there is an urgent need for a better understanding of the disease. Recent years have witnessed the critical roles of aberrant cancer cell metabolism in the maintenance of malignant properties of cancer cells, and targeting cancer cell metabolism has been regarded as a novel aspect in the development of treatments against cancer. In the present study, we identified a novel gene, AAED1 (AhpC/TSA antioxidant enzyme domain containing 1), which is upregulated in gastric cancer cells. By using lentivirus mediated transfection method, we silenced AAED1 expression and silencing of AAED1 inhibited cancer cell proliferation in vitro in gastric cancer cell lines, as demonstrated by cell viability and colony formation assay. Furthermore, we uncovered novel functions of AAED1 in regulating hypoxia inducible factor 1α (HIF1α) and the resultant aerobic glycolysis, which was measured by extracellular flux analysis. Collectively, the results of the present study uncovered novel markers that could identify the possible molecular mechanisms involved in gastric cancer.

Interaction between CD133 and PI3K-p85 promotes chemoresistance in gastric cancer cells.

Chemoresistance in gastric cancer is the leading cause of tumor recurrence and poses a substantial therapeutic challenge. The stem cell biomarker CD133 has been implicated in drug resistance of tumor-initiating cells in a number of cancers including gastric cancer. Therefore, we investigated the molecular mechanism of CD133-associated multidrug resistance in gastric cancer cells. Using CD133 overexpressing and knockdown gastric cancer cell lines, we demonstrated that loss of CD133 significantly increased the growth inhibition of chemotherapeutic agents; whereas, overexpression significantly reduced growth inhibition. Furthermore, CD133 knockdown significantly reduced the enzymatic activity of phosphatidylinositol-3 kinase (PI3K) and the expression of P-glycoprotein (P-gp), B-cell lymphoma 2 (BCL2), and phosphorylated-protein kinase B (p-AKT), but elevated the expression of BCL2 associated X (BAX). Conversely, overexpression of CD133 significantly increased PI3K enzymatic activity, expression of P-gp, BCL2, and p-AKT, and decreased BAX expression. The PI3K/AKT inhibitor LY294002 mirrored the effects of loss of CD133; whereas, the PI3K/AKT activator epidermal growth factor reproduced the effects of CD133 overexpression. To identify the interaction between CD133 and PI3K, we used site-directed mutagenesis to mutate individual tyrosine residues of CD133. We found that binding between CD133 and p85, the regulatory subunit of PI3K, was significantly reduced when tyrosine 852 was mutated. In summary, we have demonstrated that CD133 activates the PI3K/AKT signal transduction pathway through direct interaction with PI3K-p85, resulting in multidrug resistance of gastric cancer cells. These results suggest that the interaction between CD133 and PI3K-p85 may offer a novel therapeutic target in multidrug resistant gastric cancer.

Metadherin regulates actin cytoskeletal remodeling and enhances human gastric cancer metastasis via epithelial-mesenchymal transition.

Metadherin (MTDH) can be recruited to mature tight junction complexes, and it regulates mesenchymal marker protein expression in many tumors and promote cancer metastasis. This study investigated the influence of MTDH expression on gastric cancer and to elucidate the potential mechanisms by which MTDH regulates actin cytoskeletal remodeling and enhances human gastric cancer metastasis via epithelial-mesenchymal transition (EMT). Relative MTDH mRNA expression levels were assessed by quantitative real-time PCR (Q-PCR), and MTDH protein expression levels and localization were evaluated via immunohistochemical (ICH) staining. We studied the role of MTDH in cancer cell migration and invasion by modulating MTDH expression in the gastric cancer cell lines MKN45 and AGS. We also confirmed the functions of MTDH through in vivo experiments. We found that MTDH expression levels were correlated with lymph node metastasis, TNM stages and decreased OS (P=0.002, <0.001 and 0.010, respectively) in human gastric cancer and that MTDH upregulation promoted EMT in vitro. Consistent with this finding, MTDH downregulation inhibited cell migration and invasion in vitro and suppressed tumor growth and metastasis in vivo. Furthermore, MTDH knockdown regulated actin cytoskeletal remodeling and inhibited EMT. Overall, our results provide a novel role for MTDH in regulating gastric cancer metastasis.

Large Wolffian adnexal tumor of the ovary: A case report and literature review.

Female Wolffian adnexal tumor (WAT) is a rare neoplasm arising from the remnants of the mesonephric duct and <100 cases have been reported globally. The present case report describes a 73-year-old female patient with WAT in the left ovary which, to the best of our knowledge, is the largest benign WAT tumor to be reported. In addition, the present case report reviewed previous studies on the clinical characteristics and therapy for WAT and the surgery methods for female WAT of ovary were summarized. WATs are typically benign; however, a number factors may increase the risk of malignancy.

Significances of contactin-1 expression in human gastric cancer and knockdown of contactin-1 expression inhibits invasion and metastasis of MKN45 gastric cancer cells.

PURPOSE: Contactin-1 (CNTN-1) has been shown to promote cancer metastasis. Previously, we have reported that the expression of CNTN-1 was upregulated in gastric cancer tissues compared with adjacent normal tissues. Here, we investigated the significance of CNTN-1 expression and its underlying mechanism of metastasis mediated by epithelial-mesenchymal transition (EMT) in gastric cancer. METHODS: The expressions of CNTN-1 and EMT-related proteins were assayed through immunohistochemical staining of pathological specimens from patients with gastric cancer. Other methods including reverse transcriptase polymerase chain reaction, Western blotting, stably transfected against CNTN-1 into MKN45 cells, migration and invasion assays in vitro and nude mouse tumorigenicity in vivo were also utilized. RESULTS: The results revealed that CNTN-1 expression was elevated and positively correlated with metastasis, EMT-related markers and poor prognosis in patients with gastric cancer. Moreover, CNTN-1 expression might associate with invasive ability to some extent in gastric cancer cell lines KATO-Ш, SGC7901 and MKN45. Knockdown of CNTN-1 expression in MKN45 cells using short hairpin RNA (shRNA) had notable effects on cell migration and invasion, rather than proliferation in vitro and in vivo. Furthermore, suppression of CNTN-1 expression altered EMT through inhibition of transcription factor Slug, rather than Snail. CONCLUSION: Our study demonstrated that the elevated CNTN-1 expression closely correlated with cancer metastasis and patient survival, and its functions seemed to be important in migration and invasion of gastric cancer cells via EMT alteration probably mediated by inhibition of Slug. CNTN-1 may be a potential therapeutic target for gastric cancer.

[Experimental study of human bone marrow mesenchymal stem cells on regulating the biological characteristics of gastric cancer cells].

OBJECTIVE: To investigate the regulatory mechanism of bone marrow mesenchymal stem cells(BMSC) on the biological profiles of KATO-III( cell lines of gastric cancer. METHODS: Transwell cubicle was applied to build the co-cultured model in non-contact style. The differences of cell proliferation and the resistance of anti-tumour drug (5-fluoropyrimidinedione, 5-FU and Cisplatin, CDDP) between co-cultured group and single cultured group were evaluated by Cell Counting Kit 8-assay(CCK-8). The invasion ability was detected by Transwell assay. The expressions of stem cell makers, apoptosis-related factors and epithelium-mesenchymal transition (EMT)-related factors were detected by RT-PCR. RESULTS: The proliferation ability of KATO-III( cells in co-cultured group was significantly stronger than that in single cultured group. The growth rate of KATO-III( cells in co-cultured group was significantly higher than that in single cultured group after treatment of 5-FU and CDDP(P<0.05). The mRNA expression level of Bcl-2 was significantly higher in co-cultured group KATO-III( cells(P<0.05), while the mRNA expression level of Bax was significantly lower in co-cultured group KATO-III( cells(P<0.05) in comparison with those in single cultured group. As compared to KATO-III( cells in single cultured group, the number of infiltrating-membrane cells was significantly higher (37.33±5.22 vs 14.56±2.54, P<0.01) in co-cultured group, and the mRNA expression levels of Snail and N-cadherin were significantly higher in co-cultured group KATO-III( cells (P<0.05), while the mRNA expression level of E-cadherin was significantly lower in co-cultured group KATO-III( cells (P<0.05). The expressions of CD133, Nanog and Sox-2 mRNA in co-cultured group KATO-III( cells were significantly higher than those in single cultured group(P<0.05). CONCLUSIONS: In co-cultured model sharing non-contact style, BMSC can enhance such properties of KATO-III( gastric cancer cells as the proliferation, the invasion and the chemoresistance. Furthermore, the regulatory mechanisms may be related to the increase of the expressions of some stem cell markers in gastric cancer cells.

[Relationship between CD133 and chemoresistance in human gastric cancer and its associated mechanism].

OBJECTIVE: To explore the relationship between CD133(+) subsets cells in human gastric cancer (GC) and molecules of drug resistance and their sensitivity to 5-FU. METHODS: Three gastric cancer cell lines therein KATO-III(, SGC7901 and MKN45 were sorted by immunomagnetic beads cell sorting method. Then above cell lines were further divided into un-sorted GC cells, CD133(+) subgroup and CD133(-) subgroup. The expressions of CD133, P-gp, Bax and Bcl-2 were determined by RT-PCR, Western blot and immunoflurescence. Meanwhile, the sensitivity to 5-FU of three subgroups was detected by CCK-8 Kit. The apoptosis induced by 5-FU in three subgroups was determined by Hoechst 33258. RESULTS: Expressions of CD133 in three CD133(+) subgroups were significantly higher than those in un-sorted GC cells and CD133(-) subgroup (all P<0.05). Expressions of P-gp and Bcl-2 in the three GC cell lines were different (all P<0.05). There were significant differences of expressions of P-gp, Bcl-2 and Bax among CD133(+) cells, un-sorted GC cells and CD133(-) cells (all P<0.05). CCK-8 detection showed that CD133(-) subgroup of MKN45 GC cell line was more sensitive than CD133(+) cells to 5-FU (P<0.05). Hoechst 33258 staining showed that there were more apoptotic cells in CD133(-) subgroup as compared to other two subgroups, and the least apoptotic cells were observed in CD133(+) subgroup of MKN45 GC cell line (P<0.05). CD133 sirna was transfected into MKN45 GC cell line and could down-regulate the expressions of CD133, P-gp, Bcl-2 and p-Akt, while the expression of Bax increased (all P<0.05). CONCLUSIONS: CD133 may contribute to the resistance of GC cells to chemotherapy drug through P-gp, Bcl-2 and Bax. PI3K/Akt signal pathway may be involved in this process.