[Clinical characteristics and prognosis analysis of gastric cancer patients with bone metastasis]

Objectives: To investigate the clinical characteristics and prognosis of bone metastasis of gastric cancer, analyze the influencing factors of bone metastasis and the effects of different treatment methods, and provide a basis for early detection and treatment optimization of bone metastasis of gastric cancer. Methods: A total of 142 gastric cancer patients with bone metastasis admitted to the First Hospital of Lanzhou University from January 2011 to December 2021 were enrolled, including 60 cases of simple bone metastasis and 82 cases of bone metastasis combined with extraosseous metastasis. 142 patients with stage Ⅲgastric cancer without distant metastasis and 142 gastric cancer patients with visceral metastasis admitted to this hospital during the same period were also enrolled for comparison. Logistic regression analysis was used to determine the influencing factors of bone metastasis, and the Cox proportional hazards regression model was used to evaluate the influencing factors of overall survival (OS) of patients with bone metastasis. Results: Among the 142 patients with bone metastasis, poorly differentiated adenocarcinoma was the main type (123 cases), and 45 patients had simultaneous bone metastasis. Rib metastasis (100 cases), spine metastasis (88 cases), and pelvis metastasis (84 cases) were more common. A total of 110 patients had multiple bone metastasis, and 82 patients had extraosseous metastasis. Results of the stage Ⅲ gastric cancer group, the visceral metastasis group, the bone metastasis group, and the bone metastasis with extraosseous metastasis group were compared. There were significant differences in age, degree of differentiation, Borrmann type, alkaline phosphatase, lactate dehydrogenase, serum calcium, alanine aminotransferase, aspartate aminotransferase, creatine kinase isoenzyme, lymphocyte, hemoglobin, platelet, CEA, CA19-9, and CA724 (all P<0.05). Multivariate logistic regression analysis showed that Borrmann type was an independent protective factor of bone metastasis of gastric cancer (type 3: OR=0.07, 95%CI: 0.01-0.64, P=0.018). Alkaline phosphatase (OR=2.54, 95% CI: 1.07-6.01, P=0.034), serum calcium (OR=2.71, 95% CI: 1.15-6.41, P=0.023), creatine kinase isoenzyme (OR=16.33, 95% CI: 1.83-145.58, P=0.012), platelet (OR=10.08, 95% CI:1.89-53.85, P=0.007), and CA19-9 (OR=2.40, 95% CI: 1.14-5.05, P=0.021) were independent risk factors of bone metastasis of gastric cancer. The median OS of the stage Ⅲ gastric cancer group, the visceral metastasis group, the bone metastasis group, and the bone metastasis with extrabony group were 47, 13, 18, and 6 months, respectively, and the difference was statistically significant (P<0.001). The median OS of patients with bone metastasis only who underwent primary tumor surgery was 33 months, better than 6 months of patients without surgery (P=0.048). Multivariate Cox regression analysis showed that extraosseous metastasis (HR=2.45, 95% CI: 1.56-3.85, P<0.001) and decreased hemoglobin (HR=1.54, 95%CI: 1.02-2.34, P=0.042) were independent risk factors of OS of gastric cancer patients with bone metastasis. Conclusions: The prognosis of gastric cancer patients with bone metastasis alone is significantly better than that of other stage Ⅳ patients. For such patients, surgery on the primary site combined with chemotherapy after full evaluation may prolong the survival time.

[Inhibition of vascular smooth muscle cell proliferation by non-steroidal anti-inflammatory drugs]

Abnormal vascular smooth muscle cell (VSMC) proliferation is known to play an important role in the pathogenesis of atherosclerosis, restenosis and instent stenosis. Recent studies suggest that salicylates, in addition to inhibiting cyclooxygenase activity, exert an antiproliferative effect on VSMC growth both in vitro and in vivo. However, whether all non-steroidal anti-inflammatory drugs (NSAID) exert similar antiproliferative effects on VSMCs, and do so via a common mechanism of action, remains unknown. In the present study, we demonstrated that the NSAIDs, aspirin, ibuprofen and sulindac induced a dose-dependent inhibition of proliferation in rat A10 VSMCs (IC50 = 1666 mumol/L, 937 mumol/L and 520 mumol/L, respectively). These drugs did not show significant cytotoxic effects as determined by LDH release assay, even at the highest concentrations tested (aspirin, 5000 mumol/L; ibuprofen, 2500 mumol/L; and sulindac, 1000 mumol/L). Flow cytometric analyses showed that a 48 h exposure of A10 VSMCs to ibuprofen (1000 mumol/L) and sulindac (750 mumol/L) led to a significant G1 arrest (from 68.7 +/- 2.0% of cells in G1 to 76.6 +/- 2.2% and 75.8 +/- 2.2%, respectively, p < 0.05). In contrast, aspirin (2500 mumol/L) failed to induce a significant G1 arrest (68.1 +/- 5.2%). Clearer evidence of a G1 block was obtained by treatment of cells with the mitotic inhibitor, nocodazole (40 ng/ml), for the final 24 h of the experiment. Under these conditions, aspirin still failed to induce a G1 arrest (from 25.9 +/- 10.9% of cells in G1 to 19.6 +/- 2.3%) whereas ibuprofen and sulindac led to a significant accumulation of cells in G1(51.8% +/- 17.2% and 54.1% +/- 10.6%, respectively, p < 0.05). These results indicate that ibuprofen and sulindac inhibit VSMC proliferation by arresting the cell cycle in the G1 phase whereas the effect of aspirin appears to be independent of any special phase of the cell cycle. Irrespective of mechanism, our results suggest that NSAIDs might be of benefit to the treatment of vascular proliferative disorders.

[Functional analysis of the alpha1G subunit of the T-type calcium channel in cellular proliferation]

Increases of functional T-type calcium channel (T-channel) expression have been associated with cellular proliferation although evidence for this remains controversial. In the present study, we have used a variety of cellular, molecular and electrophysiological techniques to test the hypothesis that T-type channels play a causal role in the signaling pathway leading to proliferation. The results showed that stable over-expression of alpha1G T-channel subunit in HEK-293 cells conferred a significant growth advantage. Thus, cell population doubling time was reduced to 13.7 +/- 0.3 h in alpha1G transfectants, compared to control cultures (22.1 +/- 1.1 h) and flow cytometry analysis showed that this was due to a reduction in the number of alpha1G transfectants residing in the G0/G1 phases of the cell cycle compared to controls. The selective T-type calcium channel blocker, mibefradil, induced a dose-dependent inhibition of proliferation in alpha1G tansfectants. Furthermore, the Western blotting results proved that the level of protein expression of CDK2, cyclin A and cyclin E was high in alpha1G transfectants compared to control cultures. Our results demonstrate that the T-type calcium channel provides a significant growth advantage to HEK-293 cells that might occur via effects on the G1/S cell cycle mechanism.

[Mutations of genes affecting heart development of Drosophila]

Recent studies suggest that the basic molecular control mechanisms of early heart development are remarkably conserved in Drosophila, vertebrate and human being. Drosophila can be used as a prototype to explore the genetic basis of cardiogenesis in human being. Here, mutations of genes affecting heart development of Drosophila are produced by chemical mutagen methanesulfonicaeid ethyl. With staining of antibody expressed in heart precussor cells of Drosophila, 112 lethal lines were observed to show mutant phenotypes in pericardial cells. Of them, 32 lines differ in their mutant phenotypes from those of known genes. Analysis of cytogenetic mapping shows that they are located in 13 chromosomal regions without known heart-related genes, which implies that these loci contain genes probably involved in the heart development.

The effect of trithiomolybdate and some selenium compounds upon 109Cd labeled rat metallothionein in vitro: the possibilities for cadmium chelation therapy

The main binding protein for 109Cd was metallothionein after in vitro incubation of various tissue cytosol preparations obtained from rats supplemented with zinc. The exception was heart cytosol where the label was associated with higher molecular weight proteins. The metallothionein-bound 109Cd was sensitive to trithiomolybdate and moved too higher molecular weight proteins, presumably because of the creation of new stronger ligands by the association of thiomolybdate with these proteins. The 109Cd binding was affected by selenate, selenite, and selenide while molybdate, sulphate, and thiosulphate were ineffective. It is proposed that thiomolybdates should be investigated for use in the therapy of in vivo cadmium toxicity because they can remove the accumulated metal from metallothionein.