The expression profiles of CD47 in the tumor microenvironment of salivary gland cancers: a next step in histology-driven immunotherapy.

BACKGROUND: Salivary gland carcinomas (SGC) are extremely rare malignancies with only limited treatment options for the metastatic phase of the disease. Treatment with anti-CD47 antibodies could represent a potent therapy for SGCs by promoting the phagocytic clearance of tumor cells through various mechanisms. However, the efficacy of anti-CD47 therapy is largely dependent on the expression of CD47 within the tumor microenvironment (TME). MATERIALS AND METHODS: In 43 patients with SGC, we were the first to investigate the CD47 expression in both tumor cells and tumor-infiltrating immune cells (TIIC) in the center and periphery of primary tumors. We also correlated the data with the clinicopathological variables of the patients and offered novel insights into the potential effectiveness of anti-CD47 therapy in SGCs. RESULTS: We observed that the CD47+ tumor cells are outnumbered by CD47+ TIICs in mucoepidermoid carcinoma. In the tumor center, the proportion of CD47+ tumor cells was comparable to the proportion of CD47+ TIICs in most histological subtypes. In low-grade tumors, significantly higher expression of CD47 was observed in TIICs in the periphery of the tumor as compared to the center of the tumor. CONCLUSION: The reason for a high expression of 'don't eat me' signals in TIICs in the tumor periphery is unclear. However, we hypothesize that in the tumor periphery, upregulation of CD47 in TIICs could be a mechanism to protect newly recruited leukocytes from macrophage-mediated phagocytosis, while also allowing the removal of old or exhausted leukocytes in the tumor center.

Cytodiagnostics in Pneumology - State of the Art 2019.

Pulmonary cytology represents one of the basic diagnostic methods in pneumopathology. It is primarily focused on: 1) assessment of biologic nature of the pathologic process (recommended terminology and classification according to the The Papanicolaou Society of Cytopathology guidelines, 2016), 2) typing of malignant tumors (according to the WHO Classification of Tumours of the Lung, 2015), 3) assessment of mediastinal and hilar lymph nodes (including preoperative staging), 4) attaining adequate material for ancillary testing, 5) bronchoalveolar lavage (BAL) differential cell count and cytopathology studies. The need for sufficient amount of material especially in tumour diagnostics in the era of targeted therapy/personalized medicine is increasing. In pneumocytology, the diagnostic yield is greatly improved by endobronchial ultrasound-guided (EBUS) fine-needle aspiration accompanied by rapid on-site evaluation (ROSE) provided by a cytopathologist. This process gives the possibility to carefully handle and triage the specimen for diagnostic procedures as well as specific ancillary studies. When carcinoma is suspected, both cytology and biopsy specimens should be obtained whenever possible and reviewed together to achieve the highest specificity and diagnostic concordance. If no histology sample is available, attaining adequate material in the cell block becomes crucial, as it enables to carry out immmunohistochemical methods and molecular genetic testing from cytology material. For optimal acquisition, processing and testing of limited specimens in pneumocytology, as well as in pulmonary histopathology, the key issue is to establish and operate a multidisciplinary team including a cytopathologist/surgical pathologist, radiologist and pulmonologist.

[Soft tissue tumors - the view of the molecular biologist]. / Nádory mekkých tkání ocima molekulárního patologa.

Soft tissue tumors (SSTs) constitute a broad spectrum of neoplasms with diverse biological properties. Rare or unusual types are often difficult to classify. Recent studies show, that a significant subset of SSTs including many types of sarcomas are associated with specific genetic changes such as chromosomal translocations producing chimeric genes, which play a role in the pathogenesis of SSTs. Because SSTs represent a diagnostically challenging group of tumors, molecular-genetic techniques (FISH or PCR) are useful as supplementary and/or confirmatory diagnostic tools. In the present paper we demonstrate the usefulness of a combined diagnostic approach using the tools of classical histopathology and immunohistochemistry together with the molecular diagnostic approach in selected nosologic entites.

A comprehensive analysis of CD47 expression in various histological subtypes of soft tissue sarcoma: exploring novel opportunities for macrophage-directed treatments.

PURPOSE: The CD47 molecule, often referred to as the "do not eat me" signal, is frequently overexpressed in tumor cells. This signaling pathway limits phagocytosis by macrophages. Our objective was to determine CD47 abundance in various soft tissue sarcomas (STS) to investigate whether it could serve as a potential evasion mechanism for tumor cells. Additionally, we aimed to assess the prognostic value of CD47 expression by examining its association with different clinicopathological factors. This study aimed to elucidate the significance of CD47 in the context of emerging anti-tumor targeting approaches. METHODS: In this retrospective study, formalin-fixed paraffine-embedded (FFPE) tumor tissues of 55 treatment-naïve patients were evaluated by immunohistochemistry for the abundance of CD47 molecule on tumor cells. The categorization of CD47 positivity was as follows: 0 (no staining of tumor cells), 1 + (less than 1/3 of tumor area positive), 2 + (between 1/3 and 2/3 of tumor area positive), and 3 + (more than 2/3 of tumor area positive for CD47). Next, we compared CD47 abundance between different tumor grades (G1-3). We used Kaplan-Meier survival curves with log-rank test to analyze the differences in survival between patients with different CD47 expression. Moreover, we performed Cox proportional hazards regression model to evaluate the clinical significance of CD47. RESULTS: CD47 is widely prevalent across distinct STS subtypes. More than 80% of high grade undifferentiated pleiomorphic sarcoma (UPS), 70% of myxofibrosarcoma (MFS) and more than 60% of liposarcoma (LPS) samples displayed a pattern of moderate-to-diffuse positivity. This phenomenon remains consistent regardless of the tumor grade. However, there was a tendency for higher CD47 expression levels in the G3 group compared to the combined G1 + G2 groups when all LPS, MFS, and UPS were analyzed together. No significant associations were observed between CD47 abundance, death, and metastatic status. Additionally, high CD47 expression was associated with a statistically significant increase in progression-free survival in the studied cohort of patients. CONCLUSION: This study highlights the potential of the CD47 molecule as a promising immunotherapeutic target in STS, particularly given its elevated expression levels in diverse sarcoma types. Our data showed a notable trend linking CD47 expression to tumor grade, while also suggesting an interesting correlation between enhanced abundance of CD47 expression and a reduced hazard risk of disease progression. Although these findings shed light on different roles of CD47 in STS, further research is crucial to assess its potential in clinical settings.

Tertiary lymphoid structures and B cells determine clinically relevant T cell phenotypes in ovarian cancer.

Intratumoral tertiary lymphoid structures (TLSs) have been associated with improved outcome in various cohorts of patients with cancer, reflecting their contribution to the development of tumor-targeting immunity. Here, we demonstrate that high-grade serous ovarian carcinoma (HGSOC) contains distinct immune aggregates with varying degrees of organization and maturation. Specifically, mature TLSs (mTLS) as forming only in 16% of HGSOCs with relatively elevated tumor mutational burden (TMB) are associated with an increased intratumoral density of CD8+ effector T (TEFF) cells and TIM3+PD1+, hence poorly immune checkpoint inhibitor (ICI)-sensitive, CD8+ T cells. Conversely, CD8+ T cells from immunologically hot tumors like non-small cell lung carcinoma (NSCLC) are enriched in ICI-responsive TCF1+ PD1+ T cells. Spatial B-cell profiling identifies patterns of in situ maturation and differentiation associated with mTLSs. Moreover, B-cell depletion promotes signs of a dysfunctional CD8+ T cell compartment among tumor-infiltrating lymphocytes from freshly isolated HGSOC and NSCLC biopsies. Taken together, our data demonstrate that - at odds with NSCLC - HGSOC is associated with a low density of follicular helper T cells and thus develops a limited number of mTLS that might be insufficient to preserve a ICI-sensitive TCF1+PD1+ CD8+ T cell phenotype. These findings point to key quantitative and qualitative differences between mTLSs in ICI-responsive vs ICI-irresponsive neoplasms that may guide the development of alternative immunotherapies for patients with HGSOC.

A novel anti-CD47-targeted blockade promotes immune activation in human soft tissue sarcoma but does not potentiate anti-PD-1 blockade.

PURPOSE: The treatment options for metastatic soft tissue sarcomas (STSs) are limited. In most cases, immunotherapy with immune checkpoint inhibitors has not been successful so far. Macrophages dominate the immune landscape of STSs; thus, combinatorial strategies aiming at both tumor-infiltrating lymphocytes and macrophages may represent a particularly relevant treatment approach for metastatic or recurrent STSs. METHODS: In this cohort study, 66 patients who underwent surgery for STSs were enrolled. Tumor cells and tumor-infiltrating immune cells were analyzed using flow cytometry and immunohistochemistry. In cell suspensions obtained from surgical resections, human T cells were activated by superparamagnetic polymer beads and cultured at a concentration of 0.3 × 106/µl in the absence or presence of therapeutic monoclonal antibodies (anti-PD-1, anti-CD47, and anti-PD-1 + anti-CD47). Supernatants from cell suspensions were analyzed using multiplex Luminex cytokine bead-based immunoassays. RESULTS: The most profound response to anti-CD47 therapy was observed in an undifferentiated pleiomorphic sarcoma which also displayed high expression of CD47 in the tumor microenvironment. Both anti-PD-1 and anti-CD47 therapies drastically increased the production of pro-inflammatory cytokines in the tumor microenvironment of STSs, but co-administration of both agents did not further increase cytokine secretion. Furthermore, all patient samples treated with a combination of both anti-PD-1 and anti-CD47 antibodies showed a dramatic reduction in cytokine secretion. CONCLUSION: Our findings suggest that anti-PD-1 and anti-CD47 therapies do not enhance each other, and the combined application of anti-PD-1 and anti-CD47 agents in vitro limits rather than potentiates their efficacy.

Fas-Fas Ligand Interplay in the Periphery of Salivary Gland Carcinomas as a New Checkpoint Predictor for Disease Severity and Immunotherapy Response.

Salivary gland carcinomas (SGCs) are extremely morphologically heterogeneous, and treatment options for this disease are limited. Immunotherapy with immune checkpoint inhibitors (ICIs) represents a revolutionary treatment approach. However, SGCs remain largely resistant to this therapy. An increasing body of evidence suggests that resistance to ICI therapy is modulated by the Fas (CD95)-Fas ligand (FasL, CD178) interplay between tumor cells and immune cells. In this study, we examined the Fas-FasL interplay between tumor cells and tumor-infiltrating immune cells (TIICs) in the center and periphery of SGCs from 62 patients. We found that the Fas-expressing tumor cells accumulated in the center of SGC tumors with increasing tumor stage. Furthermore, this accumulation occurred regardless of the presence of TIICs expressing high levels of FasL. On the contrary, a loss of Fas-expressing TIICs with increasing tumor stage was found in the tumor periphery, whereas FasL expression in tumor cells in the tumor periphery correlated with tumor stage. These data suggest that SGC cells are resistant to FasL-induced apoptosis by TIICs but could utilize FasL to eliminate these cells in high-stage tumors to provide resistance to immunotherapy.

The Periphery of Salivary Gland Carcinoma Tumors Reveals a PD-L1/PD-1 Biomarker Niche for the Evaluation of Disease Severity and Tumor-Immune System Interplay.

The treatment options for patients with advanced salivary gland cancers (SGCs) are limited. Immune checkpoint inhibitors (ICIs) have revolutionized cancer treatment. However, the response to ICI immunotherapy is largely driven by the immune cell signatures within the tumor tissue and the para-tumoral tissue compartments. To date, there are no data on the expression of programed cell death protein-1/programed cell death protein-ligand 1 (PD-1/PD-L1) in SGC, which may enable the implementation of ICI immunotherapy for this disease. Thus, we performed an immunohistochemical analysis of PD-1 and PD-L1 expression in tumor cells and tumor-infiltrating immune cells (TIICs) in the tumor center and periphery of 62 SGC patients. The tumor periphery showed significantly higher expression of PD-L1 in tumor cells than in TIICs. Moreover, peripheral TIICs had significantly higher PD-1 expression than peripheral tumor cells. PD-1-positive tumor cells were detected exclusively in the tumor center of high-grade tumors, and most importantly, the presence of lymph node (LN) metastases and primary tumor stage significantly correlated with the presence of PD-L1-positive tumor cells in the tumor periphery. The PD-1/PD-L1 molecular signatures in SGC are clustered predominantly in the tumor periphery, reflect disease severity, and may predict the response to ICI immunotherapy in SGC patients.

Biopsy of lung lesions under CT control.

OBJECTIVES: With the increasing number of detected lung nodules and the need for morphological verification, the number of CT- controlled biopsies is increasing. The aim of this study was to assess the risks and benefits of these biopsies. METHODS: This is a prospective and observational study. We evaluated 101 punctures performed on a group of 90 consecutive patients in the Department of Radiology. RESULTS: In patients with a mean age of 66 years, with mostly accidentally detected lung nodules, we observed complications 38 times. The most common were minor pneumothoraxes or insignificant bleedings. In 6 patients, the complications were more serious, 5 times the pneumothoraxes required chest drainage, once massive hemoptysis was recorded. The lesions were successfully biopsied 78 times, the target was missed 23 times. The diagnosis of lung cancer (LC) was confirmed in 60 patients, 49 LCs were verified by puncture under CT control. 42% (25/60) of patients with LC were diagnosed in TNM stages I and II. 23% (14/60) of patients with LC were treated surgically. The remaining 30 patients most often suffered from lung metastazes (13/30), in 8 of them an inflammatory lung disease was diagnosed. 69 patients underwent bronchoscopy, in only 19% (13/69) it contributed to the diagnosis. In a model "screening like" group of 49 patients with only randomly detected lung deposits, we diagnosed LC in 76% (37/49). 49% (18/37) were in TNM stage I and II, 11 were treated surgically. CONCLUSIONS: CT-controlled biopsy of lung lesions is an effective and safe diagnostic method.

Lung cancer, pulmonary emphysema and pleural effusion: An autopsy study.

OBJECTIVES: To determine the exact incidence of lung cancer, pulmonary emphysema and pleural effusion we decided to carry out an autopsy study. METHODS: In this autopsy study carried out over two years, we compared the results of autopsy findings with the clinical data in accompanying records of the deceased. RESULTS: Among the 708 deceased subjects, there were 398 males and 310 females with a median age of 71 years. At autopsy, 55 cases of lung carcinoma (BCA) were found, of which 24 have not been identified during life (44%). Among the deceased with BCA, emphysema was also observed at autopsy in 40% of the cases. Pulmonary emphysema was described macroscopically in 28% of the full set of 708 deceased, whereas the accompanying records of the deceased described this condition in only 12% of the cases. Microscopic changes compatible with emphysema were identified in 54% of the examined lungs. Pleural effusions were described in the accompanying records of 13% of the deceased, while the autopsies showed this condition in 33% of the deceased. BCA was accompanied by effusion in 25% of the cases. CONCLUSIONS: The obtained results show that the studied conditions are present in more cases than are reported by clinicians. The study confirms the commonly accepted association between lung cancer and emphysema.

Loss of heterozygosity and human telomerase reverse transcriptase (hTERT) expression in bronchial mucosa of heavy smokers.

BACKGROUND: Lung carcinogenesis is a multistep process of accumulation of genetic changes, including loss of heterozygosity (LOH), and precedes phenotypic transformation of the bronchial mucosa. The activity of telomerase, correlating with the hTERT mRNA expression, is detectable in a majority of neoplasms. In this study, the frequency of LOH and hTERT expression in bronchial mucosa of heavy smokers in bronchoscopic biopsies was analyzed. METHODS: LOH was examined in 122 bronchial specimens from 81 smokers (67 normal mucosa/bronchitis, 12 squamous metaplasia, 28 dysplasia, 15 bronchogenic carcinoma specimens) by polymerase chain reaction (PCR) and capillary electrophoresis by using 7 fluorescence-labeled markers matching 5 chromosomal regions. hTERT expression was analyzed in 87 specimens (45 normal mucosa/bronchitis, 12 squamous metaplasia, 18 dysplasia, 12 bronchogenic carcinoma specimens) by real-time quantitative reverse-transcription PCR. RESULTS: LOH was detected in at least 1 chromosomal region in 51 of 122 (41.8%) specimens; the incidence in normal bronchial mucosa and preneoplastic lesions was similar (20%-40%); a substantial rise (87%) occurred in carcinomas. The median normalized hTERT(N) values were 6.67 in normal epithelium/chronic bronchitis, 18.38 in squamous metaplasia, 13.31 in epithelial dysplasia, and 75.46 in carcinomas. These results were significantly different (P=.0036). With an increasing number of LOH, the median value of hTERT(N) expression rose, but hTERT was expressed also in tissue samples without any LOH detection. CONCLUSIONS: Results indicated that hTERT expression, together with LOH, represent early events in lung carcinogenesis, as both were detected in precancerous lesions and in normal epithelium of heavy smokers.