Expression patterns of novel immunotherapy targets in intermediate- and high-grade lung neuroendocrine neoplasms

BACKGROUND

Advancements in immunotherapeutic approaches only had a modest impact on the therapy of lung neuroendocrine neoplasms (LNENs). Our multicenter study aimed to investigate the expression patterns of novel immunotherapy targets in intermediate- and high-grade LNENs.

METHODS

The expressions of V-domain Ig suppressor of T cell activation (VISTA), OX40L, Glucocorticoid-induced TNF receptor (GITR), and T cell immunoglobulin and mucin domain 3 (TIM3) proteins were measured by immunohistochemistry in surgically resected tumor samples of 26 atypical carcinoid (AC), 49 large cell neuroendocrine lung cancer (LCNEC), and 66 small cell lung cancer (SCLC) patients. Tumor and immune cells were separately scored.

RESULTS

Tumor cell TIM3 expression was the highest in ACs (p < 0.001), whereas elevated tumor cell GITR levels were characteristic for both ACs and SCLCs (p < 0.001 and p = 0.011, respectively). OX40L expression of tumor cells was considerably lower in ACs (vs. SCLCs; p < 0.001). Tumor cell VISTA expression was consistently low in LNENs, with no significant differences across histological subtypes. ACs were the least immunogenic tumors concerning immune cell abundance (p < 0.001). Immune cell VISTA and GITR expressions were also significantly lower in these intermediate-grade malignancies than in SCLCs or in LCNECs. Immune cell TIM3 and GITR expressions were associated with borderline prognostic significance in our multivariate model (p = 0.057 and p = 0.071, respectively).

CONCLUSIONS

LNEN subtypes have characteristic and widely divergent VISTA, OX40L, GITR, and TIM3 protein expressions. By shedding light on the different expression patterns of these immunotherapy targets, the current multicenter study provides support for the future implementation of novel immunotherapeutic approaches.

Computed Tomography-Based Quantitative Texture Analysis and Gut Microbial Community Signatures Predict Survival in Non-Small Cell Lung Cancer

This study aims to combine computed tomography (CT)-based texture analysis (QTA) and a microbiome-based biomarker signature to predict the overall survival (OS) of immune checkpoint inhibitor (ICI)-treated non-small cell lung cancer (NSCLC) patients by analyzing their CT scans (n = 129) and fecal microbiome (n = 58). One hundred and five continuous CT parameters were obtained, where principal component analysis (PCA) identified seven major components that explained 80% of the data variation. Shotgun metagenomics (MG) and ITS analysis were performed to reveal the abundance of bacterial and fungal species. The relative abundance of Bacteroides dorei and Parabacteroides distasonis was associated with long OS (>6 mo), whereas the bacteria Clostridium perfringens and Enterococcus faecium and the fungal taxa Cortinarius davemallochii, Helotiales, Chaetosphaeriales, and Tremellomycetes were associated with short OS (≤6 mo). Hymenoscyphus immutabilis and Clavulinopsis fusiformis were more abundant in patients with high (≥50%) PD-L1-expressing tumors, whereas Thelephoraceae and Lachnospiraceae bacterium were enriched in patients with ICI-related toxicities. An artificial intelligence (AI) approach based on extreme gradient boosting evaluated the associations between the outcomes and various clinicopathological parameters. AI identified MG signatures for patients with a favorable ICI response and high PD-L1 expression, with 84% and 79% accuracy, respectively. The combination of QTA parameters and MG had a positive predictive value of 90% for both therapeutic response and OS. According to our hypothesis, the QTA parameters and gut microbiome signatures can predict OS, the response to therapy, the PD-L1 expression, and toxicity in NSCLC patients treated with ICI, and a machine learning approach can combine these variables to create a reliable predictive model, as we suggest in this research.

[Small cell lung cancer heterogeneity and molecular subtypes: biological and clinical relevance]

Small-cell lung cancer (SCLC) is a highly aggressive malignancy characterised by genomic instability and early metastatic spread. Patients are typically diagnosed at advanced disease stage, when platinum-based chemotherapy with immunotherapy represents the standard therapeutic approach. The role of radiotherapy with concomitant systemic therapy is also well established in the management of SCLC patients. Although these therapeutic approaches are initially effective, most patients rapidly develop resistance. This clearly highlights the need to improve therapeutic efficacy and broaden the scope of current therapeutic strategies. Recent advances in the study of this disease, once considered homogeneous, have led to a new model of the SCLC classification scheme based on the relative expression of certain transcriptional regulators and inflammatory characteristics. New biological insights into the molecular subtypes of SCLC could lead to the implementation of subtype-specific therapeutic approaches. Here, we summarise our key findings concerning the biological and clinical relevance of SCLC molecular subtypes.

Comparative expression analysis of immune-related markers in surgically resected lung neuroendocrine neoplasms

BACKGROUND

Although immunotherapy has led to a paradigm shift in the treatment of lung cancer, the therapeutic approaches for lung neuroendocrine neoplasms (LNENs) are still limited. Our aim was to explore the immunological landscape and the expression of immune checkpoint markers in LNENs.

METHODS

Surgically removed tumor samples of 26 atypical carcinoid (AC), 30 large cell neuroendocrine carcinoma (LCNEC) and 29 small cell lung cancer (SCLC) patients were included. The immune phenotype of each tumor type was assessed by using a panel of 15 immune-related markers. As these markers are potentially expressed by immune cells and/or tumor cells, they might serve as putative targets for immunotherapy. Expression patterns were measured by immunohistochemistry and correlated with clinicopathological parameters and prognosis.

RESULTS

Unsupervised hierarchical clustering revealed distinct immunologic profiles across tumor types. Specifically, AC tumors were characterized by high tumor cell CD40 expression and low levels of immune infiltrates whereas SCLC samples had a high CD47 and Inducible T Cell Costimulator (ICOS) expression in tumor cells and immune cells, respectively. High CD70 and CD137 expression by tumor cells as well as elevated expression of CD27, Lymphocyte Activation Gene 3 (LAG3), and CD40 by immune cells were characteristic for LCNEC samples. Overall, SCLC and LCNEC tumors had a more immunogenic phenotype than AC samples. High tumor cell CD47 and CD40 expressions were associated with impaired and improved survival outcomes, respectively.

CONCLUSIONS

By providing insights into the widely divergent immunologic profiles of LNENs, our results might serve as a basis for the development of novel immunotherapy-related approaches in these devastating malignancies.

Candida expansion in the gut of lung cancer patients associates with an ecological signature that supports growth under dysbiotic conditions

Candida species overgrowth in the human gut is considered a prerequisite for invasive candidiasis, but our understanding of gut bacteria promoting or restricting this overgrowth is still limited. By integrating cross-sectional mycobiome and shotgun metagenomics data from the stool of 75 male and female cancer patients at risk but without systemic candidiasis, bacterial communities in high Candida samples display higher metabolic flexibility yet lower contributional diversity than those in low Candida samples. We develop machine learning models that use only bacterial taxa or functional relative abundances to predict the levels of Candida genus and species in an external validation cohort with an AUC of 78.6-81.1%. We propose a mechanism for intestinal Candida overgrowth based on an increase in lactate-producing bacteria, which coincides with a decrease in bacteria that regulate short chain fatty acid and oxygen levels. Under these conditions, the ability of Candida to harness lactate as a nutrient source may enable Candida to outcompete other fungi in the gut.

[The impact of the COVID-19 epidemic on the course of the most common respiratory diseases]

INTRODUCTION

SARS-CoV-2 has defined our everyday lives over the past three years and by constituting a serious risk factor for patients with pre-existing respiratory illnesses, it placed an unexpected burden on the health care systems worldwide.

OBJECTIVE

The aim of this study was to explore the association between COVID-19 and pre-existing respiratory comorbidities such as chronic obstructive pulmonary disease (COPD) and asthma.

METHOD

In our current study, we retrospectively processed the data of nearly 29 000 Hungarian patients.

RESULTS

We found that COPD was directly associated with the severity of COVID-19 and slightly increased the risk of intensive care unit admission and the need for mechanical ventilation during the SARS-CoV-2 infection. On the other hand, the presence of asthma influenced neither the severity of COVID-19 nor the need for intensive care unit admission or mechanical ventilation significantly.

DISCUSSION

International studies suggest that COPD does not significantly increase the risk of SARS-CoV-2 infection. However, the likelihood of hospitalization due to COVID-19 is much higher in COPD patients and the presence of COPD is associated with a more severe disease course. Given the structural alterations and abnormal regeneration processes of the airways that occur during lung injury in COPD patients, these individuals require increased attention and personalized rehabilitation protocols after the onset of the viral infection.

CONCLUSION

Altogether, the assessment of clinical manifestations associated with different COPD phenotypes (as well as other chronic lung diseases) and SARS-CoV-2 infection is essential for the implementation of personalized therapeutic approach in the future. Orv Hetil. 2023; 164(2): 51-56.

Thoracic irradiation as consolidation therapy in patients with extensive-stage small cell lung cancer

PURPOSE OF REVIEW

Small cell lung cancer (SCLC) is marked by an exceptionally high proliferative rate and poor prognosis. Given its high propensity to metastasize, nearly two-thirds of SCLC patients are diagnosed with extensive-stage (ES) disease when surgery is not a treatment option anymore. Over several decades, only minimal changes have been made in the therapeutic armamentarium of ES-SCLC. Recently, however, several new therapeutic avenues were defined, thus renewing the hope for patients with this recalcitrant cancer. Here, we present an overview of the most current therapeutic advances in ES-SCLC focusing in particular on consolidative thoracic radiation therapy (cTRT) and chemo-immunotherapy.

RECENT FINDINGS

The incorporation of immunotherapy in the standard-of-care of ES-SCLC patients and the resulting outcomes are both a remarkable hallmark of progress and a disappointment. Indeed, chemo-immunotherapy with or without cTRT and prophylactic cranial irradiation contributes to longer survival outcomes with minimal toxicity rates in well selected and properly monitored patients. Nevertheless, the gain in overall survival is still modest relative to that seen in many other solid tumors.

SUMMARY

Despite the encouraging results, further clinical trials are needed to determine the efficacy and safety of these therapeutic approaches, and moreover, to identify new predictive biomarkers of response.

Upregulated Apelin Signaling in Pancreatic Cancer Activates Oncogenic Signaling Pathways to Promote Tumor Development

Despite decades of effort in understanding pancreatic ductal adenocarcinoma (PDAC), there is still a lack of innovative targeted therapies for this devastating disease. Herein, we report the expression of apelin and its receptor, APJ, in human pancreatic adenocarcinoma and its protumoral function. Apelin and APJ protein expression in tumor tissues from patients with PDAC and their spatiotemporal pattern of expression in engineered mouse models of PDAC were investigated by immunohistochemistry. Apelin signaling function in tumor cells was characterized in pancreatic tumor cell lines by Western blot as well as proliferation, migration assays and in murine orthotopic xenograft experiments. In premalignant lesions, apelin was expressed in epithelial lesions whereas APJ was found in isolated cells tightly attached to premalignant lesions. However, in the invasive stage, apelin and APJ were co-expressed by tumor cells. In human tumor cells, apelin induced a long-lasting activation of PI3K/Akt, upregulated β-catenin and the oncogenes c-myc and cyclin D1 and promoted proliferation, migration and glucose uptake. Apelin receptor blockades reduced cancer cell proliferation along with a reduction in pancreatic tumor burden. These findings identify the apelin signaling pathway as a new actor for PDAC development and a novel therapeutic target for this incurable disease.

Gut microbiome functionality might be associated with exercise tolerance and recurrence of resected early-stage lung cancer patients

Impaired exercise tolerance and lung function is a marker for increased mortality in lung cancer patients undergoing lung resection surgery. Recent data suggest that the gut-lung axis regulates systemic metabolic and immune functions, and microbiota might alter exercise tolerance. Here, we aimed to evaluate the associations between gut microbiota and outcomes in lung cancer patients who underwent lung resection surgery. We analysed stool samples, from 15 early-stage lung cancer patients, collected before and after surgical resection using shotgun metagenomic and Internal Transcribed Spacer (ITS) sequencing. We analysed microbiome and mycobiome associations with post-surgery lung function and cardiopulmonary exercise testing (CPET) to assess the maximum level of work achieved. There was a significant difference, between pre- and post-surgical resection samples, in microbial community functional profiles and several species from Alistipes and Bacteroides genus, associated with the production of SCFAs, increased significantly in abundance. Interestingly, an increase in VO2 coincides with an increase in certain species and the "GABA shunt" pathway, suggesting that treatment outcome might improve by enriching butyrate-producing species. Here, we revealed associations between specific gut bacteria, fungi, and their metabolic pathways with the recovery of lung function and exercise capacity.

[Heterogeneity of small cell lung cancer: biological and clinicopathological implications]

Small cell lung cancer (SCLC; comprising approximately 14% of all lung cancer cases in Hungary) is an aggressive tumor type characterized by rapid growth and early metastasis. Although SCLC is a particularly malignant form of cancer, targeted therapies in its treatment have remained largely unsuccessful and thus there were no major therapeutic advances in the last three decades. SCLC was once considered a molecularly homogeneous malignancy. However, recent analyses led to the classification of neuroendocrine and molecular subtypes, based on the dominant expression of one of the following four transcriptional regulator genes: ASCL1, NEUROD1, YAP1 and POU2F3. Because these genetically and biologically distinct subtypes might contribute to therapeutic resistance, the better understanding of their biological and clinicopathological characteristics may help in the development of more effective SCLC therapies.

[Therapeutic possibilities in KRAS-mutant lung adenocarcinoma]

KRAS mutations are the most common gain-of-function alterations in lung adenocarcinoma (LADC) in the western countries. Although the different mutations of the KRAS gene have been identified decades ago, the development of drugs targeting the KRAS protein directly have not been successful due to the lack of small molecule binding sites and the extremely high affinity to cellular GTP. Indirect strategies to inhibit KRAS (e.g. inhibitors of farnesyltransferase, prenylation, synthetic lethal partners and KRAS downstream signaling) have so far also failed. In recent times, however several compounds have been developed that target subtype- specific KRAS mutations. Covalent KRAS G12C-specific inhibitors showed the most promising preclinical results. Below, we summarize the predictive and prognostic value of KRAS mutations in LADC as well as the current targeting strategies.

Apelin inhibition prevents resistance and metastasis associated with anti-angiogenic therapy

Angiogenesis is a hallmark of cancer, promoting growth and metastasis. Anti-angiogenic treatment has limited efficacy due to therapy-induced blood vessel alterations, often followed by local hypoxia, tumor adaptation, progression, and metastasis. It is therefore paramount to overcome therapy-induced resistance. We show that Apelin inhibition potently remodels the tumor microenvironment, reducing angiogenesis, and effectively blunting tumor growth. Functionally, targeting Apelin improves vessel function and reduces polymorphonuclear myeloid-derived suppressor cell infiltration. Importantly, in mammary and lung cancer, Apelin prevents resistance to anti-angiogenic receptor tyrosine kinase (RTK) inhibitor therapy, reducing growth and angiogenesis in lung and breast cancer models without increased hypoxia in the tumor microenvironment. Apelin blockage also prevents RTK inhibitor-induced metastases, and high Apelin levels correlate with poor prognosis of anti-angiogenic therapy patients. These data identify a druggable anti-angiogenic drug target that reduces tumor blood vessel densities and normalizes the tumor vasculature to decrease metastases.

High circulating activin A level is associated with tumor progression and predicts poor prognosis in lung adenocarcinoma

Activin A (ActA)/follistatin (FST) signaling has been shown to be deregulated in different tumor types including lung adenocarcinoma (LADC). Here, we report that serum ActA protein levels are significantly elevated in LADC patients (n=64) as compared to controls (n=46, p=0.015). ActA levels also correlated with more advanced disease stage (p<0.0001) and T (p=0.0035) and N (p=0.0002) factors. M1 patients had significantly higher ActA levels than M0 patients (p<0.001). High serum ActA level was associated with poor overall survival (p<0.0001) and was confirmed as an independent prognostic factor (p=0.004). Serum FST levels were increased only in female LADC patients (vs. female controls, p=0.031). Two out of five LADC cell lines secreted biologically active ActA, while FST was produced in all of them. Transcripts of both type I and II ActA receptors were detected in all five LADC cell lines. In conclusion, our study does not only suggest that measuring blood ActA levels in LADC patients might improve the prediction of prognosis, but also indicates that this parameter might be a novel non-invasive biomarker for identifying LADC patients with organ metastases.

[Excerpts from the collaborative lung cancer research program of Semmelweis University, the National Institute of Oncology and Korányi Institute of TB and Pulmonology (2010-2015)]

Lung cancer places a significant socio-economic burden on the Hungarian population. This overview summarizes the findings of collaborative translational lung cancer research efforts of three Hungarian flagship academic institutions, the Semmelweis University, the National Institute of Oncology and the National Koranyi Institute of TB and Pulmonology. With regards to the molecular factors regulating tumor angiogenesis, we identified the prognostic significance of apelin and erythropoietin receptor (EPOR) expression in non-small cell lung cancer (NSCLC). Furthermore, the impact of KRAS mutation subtypes and ERCC1 (excision repair cross-complementation group 1) expression on the response to platinum-based chemotherapy have been studied. We also described the epidemiology and predictive power of rare EGFR (epidermal growth factor receptor) mutations in a large Hungarian patient cohort. Lastly, the expression of molecular factors associated with NSCLC progression was studied specifically in brain metastatic matched cases series. These preclinical and clinical studies provide clinically relevant information that hopefully will contribute to the improvement of lung cancer patient care.

Apelin promotes lymphangiogenesis and lymph node metastasis

Whereas the role of the G-protein-coupled APJ receptor and its ligand, apelin, in angiogenesis has been well documented, the ability of the apelin/APJ system to induce lymphangiogenesis and lymphatic metastasis has been largely unexplored. To this end, we first show that APJ is expressed in lymphatic endothelial cells (LECs) and, moreover, that it responds to apelin by activating the apelinergic signaling cascade. We find that although apelin treatment does not influence the proliferation of LECs in vitro, it enhances their migration, protects them against UV irradiation-induced apoptosis, increases their spheroid numbers in 3D culture, stimulates their in vitro capillary-like tube formation and, furthermore, promotes the invasive growth of lymphatic microvessels in vivo in the matrigel plug assay. We also demonstrate that apelin overexpression in malignant cells is associated with accelerated in vivo tumor growth and with increased intratumoral lymphangiogenesis and lymph node metastasis. These results indicate that apelin induces lymphangiogenesis and, accordingly, plays an important role in lymphatic tumor progression. Our study does not only reveal apelin as a novel lymphangiogenic factor but might also open the door for the development of novel anticancer therapies targeting lymphangiogenesis.

Erythropoietin receptor expression is a potential prognostic factor in human lung adenocarcinoma

Recombinant human erythropoietins (rHuEPOs) are used to treat cancer-related anemia. Recent preclinical studies and clinical trials, however, have raised concerns about the potential tumor-promoting effects of these drugs. Because the clinical significance of erythropoietin receptor (EPOR) signaling in human non-small cell lung cancer (NSCLC) also remains controversial, our aim was to study whether EPO treatment modifies tumor growth and if EPOR expression has an impact on the clinical behavior of this malignancy. A total of 43 patients with stage III–IV adenocarcinoma (ADC) and complete clinicopathological data were included. EPOR expression in human ADC samples and cell lines was measured by quantitative real-time polymerase chain reaction. Effects of exogenous rHuEPOα were studied on human lung ADC cell lines in vitro. In vivo growth of human ADC xenografts treated with rHuEPOα with or without chemotherapy was also assessed. In vivo tumor and endothelial cell (EC) proliferation was determined by 5-bromo-2’-deoxy-uridine (BrdU) incorporation and immunofluorescent labeling. Although EPOR mRNA was expressed in all of the three investigated ADC cell lines, rHuEPOα treatment (either alone or in combination with gemcitabine) did not alter ADC cell proliferation in vitro. However, rHuEPOα significantly decreased tumor cell proliferation and growth of human H1975 lung ADC xenografts. At the same time, rHuEPOα treatment of H1975 tumors resulted in accelerated tumor endothelial cell proliferation. Moreover, in patients with advanced stage lung ADC, high intratumoral EPOR mRNA levels were associated with significantly increased overall survival. This study reveals high EPOR level as a potential novel positive prognostic marker in human lung ADC.

Expansion and countrywide dissemination of ST11, ST15 and ST147 ciprofloxacin-resistant CTX-M-15-type beta-lactamase-producing Klebsiella pneumoniae epidemic clones in Hungary in 2005--the new 'MRSAs'?

OBJECTIVES

To investigate the molecular epidemiology of ciprofloxacin-resistant CTX-M-15-producing Klebsiella pneumoniae epidemic clones (ECs) isolated from six nosocomial outbreaks and sporadic cases during 2005 in Hungary.

METHODS

Two hundred and eighty-one extended-spectrum beta-lactamase (ESBL)-producing K. pneumoniae clinical isolates collected from 41 centres were submitted to the National ESBL Reference Laboratory for further investigations. Of the 281 strains, 75 isolates proved to be SHV producers, whereas 6 isolates were ciprofloxacin-susceptible CTX-M-type ESBL producers. One hundred and ninety-six ciprofloxacin-resistant CTX-M-type beta-lactamase-producing isolates collected from 35 centres were subjected to macrorestriction profile analysis. Furthermore, molecular typing was performed by PCR and sequencing of several antibiotic resistance genes, plasmid profile analysis, transfer of resistance determinants and multilocus sequence typing (MLST).

RESULTS

PFGE revealed the existence of three genetic clusters defined as ECs, where 129 isolates belonged to the previously described Hungarian EC (HEC), 46 isolates to epidemic clone II (EC II) and 21 isolates to epidemic clone III (EC III), respectively. All isolates harboured plasmids ranging from 2.0 to 230 kb. PstI digestion of plasmid DNA from transconjugants/transformants revealed diverse restriction patterns from distinct ECs. Sequence analysis of beta-lactamase genes from 19 selected isolates detected bla(CTX-M-15) and bla(OXA-1) in strains from all three ECs and bla(TEM-1) in EC III isolates located on large plasmids. ISEcpI associated with CTX-M-15 was detected only on a 50 kb non-conjugative plasmid from EC III. MLST identified three allelic profiles: ST 15 (HEC), ST 11 (EC III) and the novel ST 147 (EC II), which correspond to the PFGE clusters, respectively.

CONCLUSIONS

In 2005, 97% of all CTX-M-producing K. pneumoniae isolates detected across Hungary were highly ciprofloxacin-resistant CTX-M-15 producers and represented just three stable genetic clones.

Seven generations of genetic selection for ethanol dependence in mice

An animal model of alcohol dependence is being produced by selecting mice for differences in severity of ethanol withdrawal seizures. Replicate lines of high-dependence (HA), low-dependence (LA), and control (CA) mice are being developed by within-family selection. After seven generations both (replicate) HA and LA lines have separated significantly. Some of the difference between the replicate pairs of HA and LA in the early generations was due to differences in ethanol consumption. This difference in consumption may be attributable to a difference in metabolic rate or activity level rather than to a difference in ethanol preference. Females are more susceptible to seizures than males; this appears to be due partly to their higher consumption of ethanol during treatment.