Enhanced Suppressive Activity of Regulatory T Cells in the Microenvironment of Malignant Pleural Effusions.

Cancer metastatic spread to serous cavity causes malignant pleural effusions (MPEs), indicating dismal prognosis. Tumor microenvironment can implement suppressive activity on host immune responses. Thus, we investigated the prevalence of Tregs and the relationship between them and TGF-ß and IL-10 concentrations and measured expression of FOXP3, CTLA-4, CD28, and GITR genes, as well as protein expression of selected genes in benign effusions and MPEs. The percentage of Tregs was determined by means of multicolor flow cytometry system. TGF-ß and IL-10 concentrations were measured using human TGF-ß1 and IL-10 ELISA kit. Relative mRNA expression of studied genes was analyzed by real-time PCR. The frequency of Tregs was significantly higher in MPEs compared to benign effusions; however, the level of TGF-ß and IL-10 in analyzed groups was comparable, and no correlation between concentrations of TGF-ß and IL-10 and percentage of Tregs was observed. Relative mRNA expression of all the genes was higher in CD4+CD25+ compared to CD4+CD25- cells. In CD4+CD25+ cells from MPEs, relative mRNA expression of FOXP3, CTLA-4, and CD28 genes was significantly higher than in benign effusions; however, the level of CD4+CD25+CTLA-4+ cells in analyzed groups showed no significant differences. We found numerous genes correlations in an entire CD4+CD25+ cell subset and CD4+CD25+ cells from MPEs. Enhanced suppressive activity of Tregs is observed in the microenvironment of MPEs. Understanding of relations between cellular and cytokine immunosuppressive factors in tumor microenvironment may determine success of anticancer response.

C-MET inhibitors in the treatment of lung cancer.

OPINION STATEMENT: Lung cancer is the most common malignant neoplasm and constitutes the most common neoplastic cause of death globally. The results of therapies employing standard chemotherapy are unsatisfactory. Currently, efforts are being made to personalize the therapy; numerous clinical studies are being conducted around the world to assess the efficacy and safety of agents directed at molecular targets. One of these molecular targets is the c-MET proto-oncogene, whose primary ligand is hepatocyte growth factor (HGF). C-MET hyperactivity has been observed in numerous neoplasms, including non-small-cell lung carcinoma. Prolonged or continuous activity of the receptor leads to excessive cell proliferation and is related to the development or progression of neoplastic disease. C-MET inhibitors can be classified into three groups: small-molecule tyrosine kinase inhibitors of the c-MET receptor (crizotinib, tivantinib, cabozantinib, foretinib), as well as monoclonal antibodies against c-MET (onartuzumab) and against the HGF ligand (ficlatuzumab, rilotumumab). The efficacy and safety of these agents is assessed both in monotherapy and in combination with other molecularly targeted agents. Furthermore, the toxicity profile of c-MET inhibitors is completely different from that of standard chemotherapy. The best understood c-MET inhibitor used in the treatment of non-small-cell lung carcinoma patients is crizotinib. It is registered for patients with the presence of ALK gene rearrangements after the failure of the first line of treatment based on platinum derivatives. The purpose of this present paper is to present clinical studies that assessed the efficacy and safety of c-MET inhibitors for the treatment of non-small-cell lung carcinoma, as well as current indications for the use of these molecules.

Actual status of therapeutic vaccination in non-small cell lung cancer.

Lung cancer is the leading cause of cancer-related death worldwide. Although treatment methods such as surgery, radiotherapy and/or chemotherapy have improved, prognosis remains unsatisfactory, and developing new therapeutic strategies is still an urgent matter. Immunotherapy is a novel therapeutic approach wherein activated immune cells can specifically kill tumour cells. Several lung cancer vaccines have demonstrated prolonged survival time in phase II and III trials, and several clinical trials are under investigation. However, many clinical trials involving cancer vaccination with defined tumour antigens have shown this method to work only in a small number of patients. Cancer immunotherapy is not completely effective in eradicating tumour cells because they evade host immune control.

The analysis of ALK gene rearrangement by fluorescence in situ hybridization in non-small cell lung cancer patients.

INTRODUCTION: ALK gene rearrangement is observed in a small subset (3-7%) of non-small cell lung cancer (NSCLC) patients. The efficacy of crizotinib was shown in lung cancer patients harbouring ALK rearrangement. Nowadays, the analysis of ALK gene rearrangement is added to molecular examination of predictive factors. AIM OF THE STUDY: The frequency of ALK gene rearrangement as well as the type of its irregularity was analysed by fluorescence in situ hybridisation (FISH) in tissue samples from NSCLC patients. MATERIAL AND METHODS: The ALK gene rearrangement was analysed in 71 samples including 53 histological and 18 cytological samples. The analysis could be performed in 56 cases (78.87%), significantly more frequently in histological than in cytological materials. The encountered problem with ALK rearrangement diagnosis resulted from the scarcity of tumour cells in cytological samples, high background fluorescence noises and fragmentation of cell nuclei. RESULTS: The normal ALK copy number without gene rearrangement was observed in 26 (36.62%) patients ALK gene polysomy without gene rearrangement was observed in 25 (35.21%) samples while in 3 (4.23%) samples ALK gene amplification was found. ALK gene rearrangement was observed in 2 (2.82%) samples from males, while in the first case the rearrangement coexisted with ALK amplification. In the second case, signet-ring tumour cells were found during histopathological examination and this patient was successfully treated with crizotinib with partial remission lasting 16 months. CONCLUSIONS: FISH is a useful technique for ALK gene rearrangement analysis which allows us to specify the type of gene irregularities. ALK gene examination could be performed in histological as well as cytological (cellblocks) samples, but obtaining a reliable result in cytological samples depends on the cellularity of examined materials.