New insights into the impact of primary lung adenocarcinoma location on metastatic sites and sequence: A multicenter cohort study.

INTRODUCTION: The presence of organ metastases is a major factor for unfavorable prognosis in lung adenocarcinoma (LADC). However, the influence of primary tumor location on metastatic sites and sequence has not been extensively analyzed. METHODS: We performed a multicenter cohort study, evaluating clinicopathological data of 1126 Caucasian LADC patients, focusing on the distinct location of primary tumors and metastatic sites during disease progression. RESULTS: Metastases to the lung (p < 0.001), pleura (p < 0.001) and adrenal glands (p < 0.001) occurred earlier during disease progression and central primary tumors were associated with early metastases (OR 1.43, p = 0.02). In secondary exploratory analysis we found that bone metastases were more frequent in patients with central tumors (OR 1.86, p = 0.017), whereas lung metastases in those with peripheral tumors (OR 1.35, p = 0.015). Central primary LADCs were associated with decreased median overall survival (vs. peripheral tumors, 10.2 vs. 22 months) both in univariate (HR 2.075, p = 0.001) and in multivariate (HR 1.558, p < 0.001) analyses and independent from stage and T factor. By subsequent analysis, we found that bone metastases tend to appear together with adrenal and liver metastases, and adrenal with skin, and pleural with pericardial metastases more frequently than expected if metastatic events occurred independently. CONCLUSION: This comprehensive large cohort analysis demonstrates metastatic site- and sequence-specific variations in patients with LADC. Central LADC is associated with early metastatic disease, bone involvement and, consequently, decreased survival.

[Doege-Potter syndrome with giant malignant solitary fibrous tumour of the pleura]. / Doege­Potter-szindróma a mellhártya óriás malignus szoliter fibrosus tumorával.

Infrequent solitary fibrous tumours of the pleura are associated with hypoglycaemia only in a few percent of the cases; this condition is called Doege-Potter syndrome, named after its first descriptors. Our 63 years old male patient has previously undergone clinical treatment for intrathoracic fluid accumulation on the left side caused by a giant tumour-like mass in the lower left lobe detected by CT scan. In the course of further investigations performed due to increasing load-induced dyspnoea, lung core biopsy verified low grade sarcoma in the tumour. Tumour board suggested surgery. The patient was transferred from the intensive care unit into the operation theater due to increasing dyspnoea and repeated hypoglycaemic periods in rapidly worsening general condition. Pneumonectomy and removal of the tumour was performed on the left side. Histology showed solitary fibrous tumour of the pleura corresponding to Doege-Potter syndrome. The patient was discharged without complications and underwent adjuvant chemotherapy due to pleural dissemination of the tumour observed intraoperatively. One year after surgery the patient underwent surgical removal of a locally recurrent tumour. In spite of repeated chemotherapy local and multiplex contralateral pulmonary progression was observed. Three-year survival was noted from the time of the first surgery. Orv Hetil. 2018; 159(41): 149-153.

Partial Protection of PC12 Cells from Cellular Stress by Low-Dose Sodium Nitroprusside Pre-treatment.

The PC12 rat pheochromocytoma cell line is an in vitro model system widely used for the investigation of intracellular signaling events contributing to neuronal differentiation and cell death. We found earlier that the nitric oxide donor compound sodium nitroprusside (SNP) induced apoptosis of PC12 cells if it was applied in high concentration (400 µM). Yoshioka et al. (J Pharmacol Sci 101:126-134, 2006) reported that cell death evoked by cytotoxic concentrations of SNP could be prevented by a 100 µM SNP pre-treatment in a murine macrophage cell line. The apoptosis caused by toxic-dose SNP treatment (400 µM) could be partially overcome in PC12 cells as well by the low-dose SNP pre-treatment. The partial inhibition of apoptosis was accompanied by reduced phosphorylation of certain proteins (such as stress-activated protein kinases, the p53, and the eIF2α proteins), decreased caspase activation, and less intense internucleosomal DNA fragmentation. The 100 µM SNP pre-treatment reduced the pro-apoptotic potential of certain other stress stimuli (serum withdrawal, cisplatin and tunicamycin treatments) as well, although the underlying biochemical changes were not entirely uniform. On the contrary, the 100 µM SNP pre-treatment was unable to prevent cell death caused by the protein synthesis inhibitor anisomycin. Further clarification of the above-mentioned processes may be important in understanding the mechanisms by which mild nitrosative stress protects cells against certain forms of cellular stress conditions.

The role of the p53 protein in nitrosative stress-induced apoptosis of PC12 rat pheochromocytoma cells.

PC12 rat pheochromocytoma cells are widely used to investigate signaling pathways. The p143p53PC12 cell line expresses a Val143Ala mutant p53 protein that is less capable of binding to the p53 consensus site in DNA than its wild-type counterpart. Nitric oxide (NO), depending on its concentration, is able to activate several signal transduction pathways. We used sodium nitroprusside (SNP), an NO donor compound, to analyze NO-induced cellular stress in order to clarify the mechanism and role of nitrosative stress in pathological processes, including inflammation and cancer. SNP caused cell death when applied at a concentration of 400 µM, p143p53PC12 cells showing higher sensitivity than wild-type PC12 cells. The mechanisms leading to the increased SNP-sensitivity of p143p53PC12 cells were then investigated. The 400-µM SNP treatment caused stress kinase activation, phosphorylation of the eukaryotic initiation factor eIF2α and p53 protein, proteolytic activation of protein kinase R, caspase-9, and caspase-3, p53 stabilization, CHOP induction, cytochrome c release from mitochondria, and a decline in the level of the Bcl-2 protein in both cell lines. All these SNP-induced changes were more robust and/or permanent in cells with the mutant p53 protein. We thus conclude that (1) the main cause of the SNP-induced apoptosis of PC12 cells is the repression of the bcl-2 gene, evoked through p53 stabilization, stress kinase activation, and CHOP induction; (2) the higher SNP sensitivity of p143p53PC12 cells is the consequence of the stronger and earlier activation of the intrinsic apoptotic pathway.

The effect of sodium nitroprusside on survival and stress signaling in PC12 rat phaeochromocytoma cells expressing a dominant negative RasH mutant protein.

Toxic concentrations of the second messenger nitric oxide cause cellular stress leading to cell death. Ras proteins, possible targets of nitric oxide-induced nitrosylation, may act as mediators in nitrosative stress. To analyze the possible involvement of Ras proteins in nitric oxide cytotoxicity, a PC12 rat phaeochromocytoma cell line expressing a dominant negative Ras mutant protein was used in this study. Cytotoxic concentrations of the nitric oxide donor sodium nitroprusside activated several proapoptotic mechanisms, including stimulation of the stress kinase pathways mediated by c-Jun N-terminal kinase (JNK) and p38 mitogen-activated protein kinase (MAPK), inhibition of the translation initiation factor eIF2α, induction and phosphorylation of the p53 protein, and inhibited Akt-mediated antiapoptotic signaling, independent of Ras function. Simultaneously, Ras-dependent stimulation of the prosurvival ERK pathway was also observed, followed by an increased activation of the caspase-9/caspase-3 cascade in cells with impaired Ras function. It is concluded that nitric oxide stimulation of multiple signaling pathways contributes to the cell death program, whereas concomitant activation of the Ras/ERK pathway provides a certain degree of protection.

Sodium nitroprusside, a nitric oxide donor, fails to bypass the block of neuronal differentiation in PC12 cells imposed by a dominant negative Ras protein.

Nitric oxide (NO) is a mediator of a diverse array of inter- and intracellular signal transduction processes. The aim of the present study was to analyze its possible role as a second messenger in the process of neuronal differentiation of PC12 pheochromocytoma cells. Upon NGF treatment wildtype PC12 cells stop dividing and develop neurites. In contrast, a PC12 subclone (designated M-M17-26) expressing a dominant-negative mutant Ras protein keeps proliferating and fails to grow neurites after NGF treatment. Sodium nitroprusside (SNP), an NO donor, was found to induce the p53 protein and to inhibit proliferation of both PC12 and M-M17-26 cells, but failed to induce neuronal differentiation in these cell lines. Key signaling pathways (the ERK and Akt pathways) were also not affected by SNP treatment, and the phosphorylation of CREB transcription factor was only slightly stimulated. It is thus concluded from the results presented in this paper that NO is unable to activate signaling proteins acting downstream or independent of Ras that are required for neuronal differentiation.