Lighting up the fire in cold tumors to improve cancer immunotherapy by blocking the activity of the autophagy-related protein PIK3C3/VPS34.

Cancer immunotherapy based on Immune checkpoint blockade (ICB) is a promising strategy to treat patients with advanced highly aggressive therapy-resistant tumors. Unfortunately, the clinical reality is that only a small number of patients benefit from the remarkable clinical remissions achieved by ICB. Experimental and clinical evidence claimed that durable clinical benefit observed using ICB depends on the immune status of tumors, notably the presence of cytotoxic effector immune cells. In our paper, we revealed that genetically targeting the autophagy-related protein PIK3C3/VPS34 in melanoma and colorectal tumor cells, or treating tumor-bearing mice with selective inhibitors of the PIK3C3/VPS34 kinase activity, reprograms cold immune desert tumors into hot, inflamed immune infiltrated tumors. Such reprograming results from the establishment of a proinflammatory signature characterized by the release of CCL5 and CXCL10 in the tumor microenvironment, and the subsequent recruitment of natural killer (NK) and CD8+ T cells into the tumor bed. Furthermore, we reported that combining pharmacological inhibitors of PIK3C3/VPS34 improves the therapeutic benefit of anti-PD-1/PD-L1 immunotherapy. Our results provided the proof-of-concept to set-up innovative clinical trials for cold ICB-unresponsive tumors by combining PIK3C3/VPS34 inhibitors with anti-PDCD1/PD-1 and anti-CD274/PD-L1.

Influence of fingolimod on basic lymphocyte subsets frequencies in the peripheral blood of multiple sclerosis patients - preliminary study.

BACKGROUND: Fingolimod is a drug administered orally to adult patients treated for relapsing remitting course of multiple sclerosis (MS). Mode of action of fingolimod is based on intense S1P1 receptor stimulation and "arresting" lymphocytes in lymphatic organs. Objective of the research was to assess changes in the frequencies of basic lymphocyte subsets in patients treated for multiple sclerosis with the use of fingolimod. MATERIAL AND METHODS: Study group comprised of 25 previously untreated adult patients with MS. Venous blood samples were collected from each patient before and one month, three months and six months after treatment initiation. Peripheral blood lymphocyte immunophenotype was assessed with a set of monoclonal antibodies bounded to appropriate fluorochromes and flow cytometer FACSC alibur. Statistical analysis of the results was conducted using Statistica 9.0 software. RESULTS: Before fingolimod administration median of lymphocyte subsets percentage in each patient was in reference range. After 1 month of treatment we noticed significant changes in frequencies of following lymphocyte subsets: NK cells - 51.22% (p = 0.016), T CD4+ cells - 11.58% (p = 0.01), T CD4+:T CD8+ cells ratio - 0.61 (p = 0.005). After 3 and 6 months of treatment there was further increase of deviation from normal state. CONCLUSIONS: The use of fingolimod is associated with profound changes in lymphocyte subsets distribution, which might bear a risk of the development of cellular immune deficiency symptoms.

Morphological analyses of caseous necrosis correlated to CD68+ and CD8+ cells in biopsies of tuberculous pleurisy / Análisis morfológico de la necrosis caseosa y su correlación con células CD68+ y CD8+ en biopsias de pleuritis tuberculosa

Tuberculosis is the most prevalent infectious disease in the world. Granuloma formation and caseous necrosis are hallmarks of M. tuberculosis infection and they represent the protective and inflammatory reactions in the infected tissues. The molecular mechanisms that mediate granuloma necrosis are still not well understood. Objectives: To immunolocalize and correlate the amounts of CD68+ macrophages and CD8+ lymphocytes to caseous necrosis extension in granulomas of tuberculous pleurisy. Methods: The study is a retrospective analysis of 30 pleural biopsies with histopathological diagnosis of chronic granulomatous pleurisy with caseous necrosis. These biopsies were classified according to necrosis intensity as minimal (N1), moderate (N2) and intense (N3). The number of granulomas was also observed and categorized as G1 (1 to 4 granulomas per section), G2 (5 to 8 granulomas per section), and G3 (more than 8 granulomas per section). Results: The means of CD68+ cells counts per mm² in N1, N2 and N3 categories of necrosis were 1,287 +/- 254, 1086 +/- 181 and 930 +/- 115 respectively. The means for CD8+ cells were 483.7 +/- 396, 366.3 +/- 43 and 558 +/- 53 cells per mm² in N1, N2 and N3 respectively. Conclusions: There were no significant statistical correlations between necrosis extension and cell counts. In analyzed biopsies, the number of CD68+ cells was significantly higher than the number of CD8+ cells.

La tuberculosis es una de las enfermedades más prevalentes en el mundo. La formación del granuloma junto con la necrosis caseosa son características propias de la infección por M. tuberculosis y representan reacciones inflamatorias y protectoras en los tejidos infectados. No se conocen bien los mecanismos moleculares que median la necrosis en el granuloma. Los objetivos fueron inmunolocalizar y correlacionar la cantidad de macrófagos CD68+ y linfocitos CD8+ con la extensión de la necrosis caseosa, en los granulomas de tuberculosis pleural. Análisis retrospectivo que incluyeron 30 biópsias con diagnóstico histopatológico de tuberculosis pleural granulomatosa crónica con necrosis caseosa. Estas biópsias fueron clasificadas según la intensidad de necrosis como mínima (N1), moderada (N2) e intensa (N3). También se determinó el número de granulomas, que fueron clasificados como G1 (1 a4 granulomas por sección), G2 (5 a 8 granulomas por sección), y G3 (más de 8 granulomas por sección). La cuantificación de células CD68+ por mm² en las categorías N1, N2 y N3 de necrosis fue de 1,287 +/- 254; 1086 +/-181 y 930 +/- 115, respectivamente. La cuantificación de las células CD68+ fue de 483,7 +/- 396; 366,3 +/- 43 y 558 +/- 53 células por mm² para N1, N2 y N3, respectivamente. No hubo correlación estadísticamente significativa entre la extensión de la necrosis y la cuantificación celular. El número de células CD68+ fue significativamente mayor que el número de células CD8+ en las biópsias analizadas.