Proteasome Subunit Alpha Type 7 Promotes Proliferation and Metastasis of Gastric Cancer Through MAPK Signaling Pathway.

BACKGROUND: Proteasome subunit alpha type 7 (PSMA7) shows a carcinogenic effect on various human malignancies, but its role and regulatory mechanism in gastric carcinoma (GC) remain unclear. AIMS: This study aimed to explore the role and mechanism of PSMA7 in GC. METHODS: In this study, PSMA7 expressions in GC cells and tissues were detected, and relationships between PSMA7 and clinicopathological features were explored. Then, PSMA7 levels in human GC cells were intervened, and changes in cell biological behavior were observed in vitro and vivo. Key proteins and downstream factors of MAPK signaling pathway were detected after PSMA7 intervention. RESULTS: PSMA7 was upregulated in GC tissues and cell lines. PSMA7 overexpression was significantly associated with poor pTNM, cTNM stage, and high HP infection. PSMA7 can promote proliferation, invasion, and metastasis of GC cells in vitro and vivo. Furthermore, PSMA7 expression affected the phosphorylation level of JNK, P38, ERK and the expressions of their downstream factors Ap-1, c-myc, P53. CONCLUSION: PSMA7 can promote GC proliferation, invasion, and metastasis through MAPK signaling pathway in GC cells.

Combination of chemotherapy and immune checkpoint therapy by the immunoconjugates-based nanocomplexes synergistically improves therapeutic efficacy in SCLC.

Although the etoposide and carboplatin (EP) combination strategy has been the first-line chemotherapy, patients with extensive-stage disease small-cell lung cancer (SCLC) still have poor survival outcomes. Our retrospective analysis revealed that 46 patients with SCLC only achieved medium overall survival (OS) of 11.6 months after treated by EP. Recently, it was demonstrated that combination therapy of PD1/PD-L1 immune checkpoint blocker and EP could significantly improve the OS of SCLC patients. However, the serious treatment-related toxicity leaded to a high rate of treatment-discontinuation or even death. In the present study, we have developed a novel TPP1-conjugated nanocomplex, abbreviated as TPP1NP-EP, which was co-loaded with carboplatin (CBP) and etoposide (VP16). The TPP1 was a PD-L1 targeting peptide and conjugated on the surface of nanocomplex by a matrix metalloproteinase (MMP-2/9)-cleavable peptide linker sequence PLGLAG. For dual-loading of CBP and VP16, the CBP was chemically conjugated with poly(ethylene glycol) (PEG)-poly(caprolactone) (PCL) by pH-sensitive hydrazone bond and the VP16 was physically encapsulated by emulsion-solvent evaporation method. In vitro and in vivo experiments demonstrated an excellent anti-tumor effect of TPP1NP-EP on SCLC and improved safety. In conclusion, the present study has provided a promising strategy for treatment of malignant SCLC.

[Effect of MG-132 upon the expression of intercellular adhesion molecule-1 in cerulein-induced acute pancreatitis in mice].

OBJECTIVE: To investigate the effects of the proteasome inhibitor MG-132 upnon NF-kappaB and the expression of intercellular adhesion molecule-1 (ICAM-1) in cerulein-induced acute pancreatitis (AP) in mice. METHODS: Forty-five BalB/c mice were randomly allocated into nine groups: control 3, 6, 12 h group (n = 5); AP 3, 6, 12 h group (n = 5) and MG-132 3, 6, 12 h group (n = 5). AP group was induced by an ip injection of 100 microg/kg cerulein six times with a 1 h interval. Control group received physiological saline likewise. MG-132 group was injected ip with 10 mg/kg MG-132 at 30 min before induction of AP. The levels of serum amylase and soluble ICAM-1 (sICAM-1) were tested. The pathological changes of pancreas were observed. The expression of NF-kappaB proteins was examined by immunohistochemistry and the expression of ICAM-1 mRNA analyzed by reverse transcription-polymerase chain reaction (RT-PCR). RESULTS: In MG-132 group, the levels of serum amylase (U/L) and sICAM-1 (pg/ml) markedly decreased in comparison with AP group (1629 +/- 59, 1794 +/- 123, 2910 +/- 152 vs 1282 +/- 61, 1525 +/- 103, 1809 +/- 117, 133 +/- 10, 157 +/- 10, 217 +/- 43 vs 106 +/- 6, 135 +/- 4, 163 +/- 19, P < 0.05 or P < 0.01); the scores of pathological changes decreased in pancreas (5.7 +/- 1.0, 7.1 +/- 1.2, 9.6 +/- 2.1 vs 3.2 +/- 1.0, 5.3 +/- 1.0, 6.9 +/- 0.8, P < 0.05 or P < 0.01);the expression of NF-kappaB protein (3.8 +/- 1.1, 4.6 +/- 1.2, 6.7 +/- 0.4 vs 1.9 +/- 0.6, 3.1 +/- 1.0, 4.7 +/- 1.0, P < 0.05 or P < 0.01) were significantly lowered than those in AP group. ICAM-1 mRNA also decreased more than those in AP group (0.3 +/- 0.1, 1.0 +/- 0.2, 1.2 +/- 1.0 vs 0.3 +/- 0.2, 1.8 +/- 0.2, 2.1 +/- 0.2, P < 0.05 or P < 0.01). CONCLUSIONS: The proteasome inhibitor MG-132 can obviously improve the outcome of acute pancreatitis. And the mechanism may be related to the down-regulated expression of cytokines, including adhesion molecules, through the suppression of NF-kappaB activation.

[Expression of PSMA 7 and its effect on proliferation, invasion, migration and tumorigenesis of gastric cancer].

OBJECTIVE: To study the expression of PSMA7 and its effect on proliferation, invasion and migration of gastric cancer and subcutaneous tumorigenesis in nude mice. >and subcutaneous tumorigenesis in nude mice. METHODS: Specimens of tumor tissues and paired adjacent tissues were collected from 60 patients with gastric cancer for detecting the expression levels of PSMA7 using immunohistochemical method. Gastric cancer cell line SGC7901 was transfected with a lentiviral vector to inhibit PSMA7 expression, and the changes in cell proliferation and invasion were observed using cell counting kit-8 (CCK-8), clone formation assay and Transwell assay. A BALB/c mouse model bearing subcutaneous gastric cancer xenograft was established using SGC7901 cells with stable PSMA7 knockdown to assess the effect of low expression of PSMA7 on xenograft growth. RESULTS: Gastric cancer tissues expressed significantly higher levels of PSMA7 than the paired adjacent tissues (P < 0.05). In SGC7901 cells, interference of PSMA7 expression significantly inhibited the cell proliferation and invasion (P < 0.05). In the tumor-bearing BALB/c mice, the xenografts derived from SGC7901 cells with PSMA7 expression interference showed significant growth suppression as compared with the control xenografts (P < 0.05). CONCLUSIONS: PPSMA 7 is overexpressed in gastric cancer tissues, and PSMA7 knockdown inhibits the proliferation, invasion, migration and subcutaneous tumorigenesis of gastric cancer cells in nude mice.

Overexpression of PSMA7 predicts poor prognosis in patients with gastric cancer.

Gastric cancer (GC) is the fourth most common tumor and the second most common cause of cancer-associated mortality worldwide. Current tumor biomarkers for GC, such as serum carcinoembryonic antigen and carbohydrate antigen 19-9, are not ideal due to their limited role as prognostic indicators for GC. Proteasome subunit α7 (PSMA7) is a multifunctional protein, which has been revealed to be involved in the development and progression of various types of malignancy. However, little is known about the role of PSMA7 in GC. In the present study, PSMA7 was identified to be overexpressed at the mRNA and protein levels in GC tissues, compared with in non-tumor tissues, using reverse transcription-quantitative PCR and immunohistochemistry. Furthermore, PSMA7 expression is associated with tumor invasion, lymph node metastasis, distant metastasis, and Tumor-Node-Metastasis stage. Univariate and multivariate Cox regression analysis identified that PSMA7 expression is an independent prognostic factor for poor survival. Kaplan-Meier survival curves revealed that high PSMA7 expression is associated with a poor prognosis in patients with GC. Overall, the results of the present study suggested that PSMA7 may be a promising biomarker for the prognosis of GC, and may represent a new diagnostic marker and molecular therapeutic target for GC.

Diagnostic value of OMOM capsule endoscopy for small bowel diseases in adults.

The present study aimed to determine the diagnostic yield of OMOM capsule endoscopy for small bowel diseases in adults. A total of 89 patients, including 45 cases of obscure abdominal pain, 22 of chronic diarrhea, 18 of obscure gastrointestinal bleeding and 4 of obscure anemia were enrolled in the present study. The transit time of the endoscopy capsule in the digestive tract was recorded and the testing results were analyzed. All detections were completed except for four capsule retentions and the completion rate was 95.51%. The average transit time of the endoscopy capsule in the esophagus, stomach and small intestine was 62.18±64.23 sec, 67.46±63.13 and 346.53±102.81 min, respectively. Of the 89 patients, 54 (60.67%) were found to have lesions, among which 19 had mucosal erosion (21.35%), 15 had anabrosis (16.85%), 9 were diagnosed with polyps (10.11%), 5 with angiodysplasia (5.62%); furthermore, tumors were identified in 5 patients (5.62%) and ancylostomiasis in 1 patient (1.12%). The results confirmed the feasibility and validity of OMOM capsule endoscopy for diagnosing small bowel diseases in adults.

High expression of TROP2 is correlated with poor prognosis of oral squamous cell carcinoma.

Human trophoblastic cell-surface antigen 2 (TROP2) is a cell surface glycoprotein that exhibits high expression in various carcinomas but low or no expression in normal tissues. High TROP2 expression plays an important role in promoting tumor development and aggressiveness, which is correlated with reduced patient survival. However, there are few studies regarding TROP2 in relation to both oral squamous cell carcinoma (OSCC) and oral potentially malignant lesions. The expression of TROP2 protein and mRNA was investigated in OSCC tissues, oral potentially malignant lesion tissues, and normal oral tissues using immunohistochemistry and quantitative real-time polymerase chain reaction (qRT-PCR). The association between TROP2 expression and clinicopathological characteristics of OSCC was also analyzed, and the prognostic value of TROP2 was evaluated. The expression of TROP2 protein and mRNA were both higher in OSCC tissues than in oral potentially malignant lesion tissues or normal oral tissues. Positive TROP2 expression was related to differentiation, lymph node metastases, TNM stage, perineural infiltration, and vascular invasion. Poor overall survival was associated with high TROP2 expression and other factors associated with poor overall survival including poor differentiation, lymph node metastasis, TNM stage, vascular invasion, and perineural invasion in univariate analyses. TROP2 expression as well as TNM stage and vascular invasion were independent prognostic factors associated with the overall survival of OSCC patients in multivariate analyses. In summary, High TROP2 expression is associated with poor overall survival and serves as an independent prognostic factor in OSCC. The results suggest that TROP2 expression could be an effective prognostic biomarker for OSCC.