The Role of REV-ERB Receptors in Cancer Pathogenesis.

REV-ERB receptors are members of the nuclear receptor superfamily of proteins, which act as both intracellular receptors and transcription factors, therefore modulating the expression of target genes. REV-ERBs act as transcription repressors because of their unique structure. Their predominant role involves the control of peripheral circadian rhythmicity by participating in a transcription-translation feedback loop with other major clock genes. Regarding their role in cancer pathogenesis, recent studies in various cancerous tissues have revealed that their expression was downregulated in the majority of the cases. Dysregulation of their expression was also implicated in cancer-associated cachexia. The pharmacological restoration of their effects is feasible with synthetic agonists, which have been explored in preclinical studies but with scarce data. There is a need for further investigation, primarily with mechanistic studies, on the effect of the REV-ERB-induced circadian rhythm deregulation in carcinogenesis and cancer-related systemic effects, such as cachexia, in order to address the potential of relevant therapeutic implications.

Mechanisms of resistance to cyclin-dependent kinase 4/6 inhibitors.

Cyclin-dependent kinase (CDK) 4/6 inhibitors have emerged in the treatment of metastatic hormone receptor (HR)-positive and human epidermal growth factor receptor 2 (HER2)-negative breast cancer. However, most patients will eventually present disease progression, highlighting the inevitable resistance of cancer cells to CDK4/6 inhibition. Several studies have suggested that resistance mechanisms involve aberrations of the molecules that regulate the cell cycle, and the re-wiring of the cell to escape CDK4/6 dependence and turn to alternative pathways. Loss of retinoblastoma function, overexpression of CDK 6, upregulation of cyclin E, overexpression of CDK 7, and dysregulation of several signaling pathways, notably the PI3/AKT/mTOR pathway, have been implicated in the development of resistance to CDK4/6 inhibitors. Overlap with endocrine resistance mechanisms might be possible. Combinational therapeutic strategies should be explored in order to prevent resistance and optimize the management of patients after progression under CDK 4/6 inhibition.

Programmed Death-Ligand 1 as a Regulator of Tumor Progression and Metastasis.

Programmed cell death protein 1 (PD-1)/programmed death-ligand 1 (PD-L1) immune checkpoint has long been implicated in modeling antitumor immunity; PD-1/PD-L1 axis inhibitors exert their antitumor effects by relieving PD-L1-mediated suppression on tumor-infiltrating T lymphocytes. However, recent studies have unveiled a distinct, tumor-intrinsic, potential role for PD-L1. In this review, we focus on tumor-intrinsic PD-L1 signaling and delve into preclinical evidence linking PD-L1 protein expression with features of epithelial-to-mesenchymal transition program, cancer stemness and known oncogenic pathways. We further summarize data from studies supporting the prognostic significance of PD-L1 in different tumor types. We show that PD-L1 may indeed have oncogenic potential and act as a regulator of tumor progression and metastasis.

Tumor Dormancy: Implications for Invasion and Metastasis.

Tumor dormancy refers to a critical stage of cancer development when tumor cells are present, but cancer does not progress. It includes both the concept of cellular dormancy, indicating the reversible switch of a cancer cell to a quiescent state, and that of tumor mass dormancy, indicating the presence of neoplastic masses that have reached cell population equilibrium via balanced growth/apoptosis rates. Tumor dormancy provides the conceptual framework, potentially explaining a major challenge in clinical oncology, tumor recurrence, which may occur years after cancer diagnosis. The mechanisms by which tumors are kept dormant, and what triggers their reawakening, are fundamental questions in cancer biology. It seems that a plethora of intracellular pathways and extracellular factors are involved in this process, rewiring the cells to plastically alter their metabolic and proliferative status. This phenomenon is highly dynamic in space and time. Mechanistic insights into both cellular and tumor dormancy have provided the rationale for targeting this otherwise stable period of cancer development, in order to prevent recurrence and maximize therapeutic benefit.

Lung cancer in patients with Idiopathic Pulmonary Fibrosis. A retrospective multicenter study in Greece.

BACKGROUND: Abundant evidence supports an association between Idiopathic Pulmonary Fibrosis (IPF) and lung cancer development. Data on diagnosis and management of patients with IPF and lung cancer are still scarce. PATIENTS AND METHODS: This was a retrospective multicenter study, enrolling 1016 patients with IPF from eight different centers between 2011 and 2018 in Greece. Our aim was to estimate prevalence of lung cancer in patients with IPF in Greece. RESULTS: We identified 102 cases of patients with IPF and lung cancer (prevalence = 10.03% n = 102/1016, mean age±SD = 71.8 ± 6.9, 96 males, mean FVC±SD = 72.7 ± 19.7, mean DLCO±SD = 44.5 ± 16.3). We identified 85 cases (83.3%) of non-small cell lung cancer (35 squamous, 28 adenocarcinoma), and 15 cases (14.7%) of small cell lung cancer. Primary lesion was localized in lower lobes in 57.1% of cases. Lung cancer was diagnosed post IPF diagnosis (mean latency time + SD = 33.2 + 36.1 months) in 57.6% of patients and synchronously in 36.5% of patients. Chemotherapy was applied in 26.7% of cases, while 34.7% of patients underwent surgery. Median survival of patients with IPF and lung cancer was 27.4 months (95% CI: 20.6 to 36.8). CONCLUSIONS: IPF is a risk factor for lung cancer development. In line with current literature, squamous cell carcinoma is the most common histologic subtype in patients with IPF. Large randomized controlled studies on the management of patients with IPF and lung cancer are sorely needed.

Do we need prophylactic anticoagulation in ambulatory patients with lung cancer? A review.

Venous thromboembolism is a common complication of malignancy. Lung cancer is considered one of the most thrombogenic cancer types. Primary thromboprophylaxis is not currently recommended for all ambulatory patients with active cancer. In the present narrative review we aim to summarize recent data on the safety and efficacy of primary thromboprophylaxis as well as on venous thromboembolism risk assessment, focusing on ambulatory patients with lung cancer. A potential benefit from prophylactic anticoagulation with low molecular weight heparins in terms of venous thromboembolism risk reduction and increased overall survival in patients with lung cancer, without a significant increase in bleeding risk, has been reported in several studies. Recent studies also reveal promising results of direct oral anticoagulants regarding their efficacy as primary thromboprophylaxis in patients with cancer, including those with lung cancer. However, the use of different study methodologies and the heterogeneity of study populations among the trials limit the extraction of definite results. More randomized, controlled trials, restricted to a well-characterized population of patients with lung cancer, are greatly anticipated. The use of risk assessment tools for stratification of venous thromboembolic risk is warranted. The development of an accurate and practical risk assessment model for patients with lung cancer represents an unmet need.

Immune Checkpoint Inhibitor-Related Pneumonitis.

Immune checkpoint inhibitors are novel agents that have been proved efficacious in a variety of cancer types, but they are associated with a unique set of organ-specific, immune-related adverse events. Among them, immune-related pneumonitis requires special attention because it is difficult to diagnose and potentially lethal. Accumulating real-world epidemiological data suggest that immune-related pneumonitis is more frequent than previously reported. Its diagnosis requires exclusion of other causes and assessment of radiographic features on high-resolution CT of the chest. Management of immune-related pneumonitis is based on the use of immunosuppressants. Future research should be focused on finding predictive biomarkers for immune-related pneumonitis as well as optimizing its management.

Human disease caused by Streptococcus alactolyticus: a case report of native valve infective endocarditis and review of the literature.

Streptococcus alactolyticus, a member of the Streptococcus bovis/Streptoccus equinus complex, is primarily hosted in the gastrointestinal tract of animals and rarely of humans, with only scarce reports relating to human disease. We herein present a case of subacute infective endocarditis (IE) caused by S. alactolyticus in a 64-year old male with pre-existing mitral prolapse. Despite a 10-month history of low-grade fever and weight loss, the diagnosis of IE was triggered by left quadrant abdominal pain which revealed splenic infarcts on computed tomography. A definitive diagnosis of IE was subsequently established by four consecutive blood cultures positive for S.alactolyticus plus demonstration of a vegetation on the mitral valve by trans-esophageal ultrasound. Further workup revealed multiple embolic phenomena including brain and spine. A dental abscess was identified as the most probable origin of the bacteraemia, while colonoscopy revealed no evidence of cancer. The patient recovered uneventfully with antibiotic treatment and underwent successful cardiac surgery post-discharge. Although rare, IE caused by S. alactolyticus may be severe and of obscure origin; oral cavity should not be overlooked as a possible origin. Attention should be given in patients with preexisting risk factors.

Pulmonary nocardiosis associated with Cushing's disease: a case report.

Nocardia spp. is a genus of Gram-positive bacteria which can cause cutaneous, pleuropulmonary, or disseminated disease. The latter two forms are encountered in immunocompromised patients, with prolonged usage of corticosteroids being a well-recognized risk factor. However, endogenous Cushing's syndrome is less frequently associated with nocardiosis. We report on a 40-year-old woman who presented for further workup of abnormal findings in the chest computed tomography (three lung nodules, one of which being cavitary). She underwent trans-thoracic fine-needle lung aspiration of the cavitary nodule, which led to the diagnosis of lung nocardiosis. Moreover, the identification of cushingoid features from the history and clinical examination initiated further investigation with hormonal laboratory assessment and bilateral inferior petrosal sinus sampling which established the diagnosis of pituitary adrenocorticotropic hormone (ACTH) hypersecretion (Cushing's disease).  We conclude that pulmonary nocardiosis can be an opportunistic infection as well as a presenting manifestation of Cushing's disease.

Molecular interactions of antibodies with PD-1/PD-L1 proteins.

Aim: To compare the protein-protein interactions of antibodies targeting PD-1 and its ligand (PD-L1) with their targets in an attempt to explain the antibodies' binding affinity. Materials & methods: The structural features of complexes between pembrolizumab, nivolumab, durvalumab, atezolizumab, avelumab and PD-1/PD-L1 are described, with the use of software and based on crystallographic data. Results: Pembrolizumab has more structural features, including the number and type of the bonds and total binding surface area, which could rationalize its different clinical behavior compared with nivolumab. Similarly, protein-protein interactions with PD-L1 differ among durvalumab, atezolizumab and avelumab. Conclusion: Differential protein-protein interactions between antibodies and PD-1/PD-L1 may indicate differential clinical activity; however, further research is needed to provide evidence.

This study looked at different immunotherapy drugs used to treat cancer. These drugs bind to two different proteins, called PD-1 and PD-L1, that are part of our immune system. These proteins usually act as brakes in our immune system. The drugs block the brakes, which boosts the immune system and improves the immune defense against cancer. Using computer images, the authors compared how each drug binds to PD-1/PD-L1. The results showed that these drugs bind to PD-1 and PD-L1 with different chemical bonds. These bonds can be smaller or larger depending on the drug. The drugs' different chemical bonds with PD-1/PD-L1 might show that they do not act exactly the same when they are given to patients. However, further studies are needed for more information.

CAR-T Cell Therapy in Pancreatic and Biliary Tract Cancers: An Updated Review of Clinical Trials.

BACKGROUND: Pancreatic and biliary tract cancers are digestive system tumors with dismal prognosis and limited treatment options. The effectiveness of conventional surgical interventions, radiation therapy, and systemic therapy is restricted in these cases. Furthermore, clinical trials have shown that immunotherapy using immune checkpoint inhibitors has only demonstrated modest clinical results when applied to patients with pancreatobiliary tumors. This highlights the importance of implementing combination immunotherapy approaches or exploring alternative therapeutic strategies to improve treatment outcomes. MATERIALS AND METHODS: We reviewed the relevant literature on chimeric antigen receptor (CAR)-T cell therapy for pancreatobiliary cancers from PubMed/Medline and ClinicalTrials.gov and retrieved the relevant data accordingly. Attention was additionally given to the examination of grey literature with the aim of obtaining additional details regarding ongoing clinical trials. We mainly focused on abstracts and presentations and e-posters and slides of recent important annual meetings (namely ESMO Immuno-Oncology Congress, ESMO Congress, ASCO Virtual Scientific Program, ASCO Gastrointestinal Cancers Symposium). RESULTS: CAR-T cell therapy has emerged as a promising and evolving treatment approach for pancreatic and biliary tract cancer. This form of adoptive cell therapy utilizes genetic engineering to modify the expression of specific antibodies on the surface of T cells enabling them to target specific cancer-associated antigens and to induce potent anti-tumor activity. The aim of this review is to provide an updated summary of the available evidence from clinical trials that have explored the application of CAR-T cell therapy in treating pancreatobiliary cancers. CONCLUSIONS: While the utilization of CAR-T cell therapy in pancreatobiliary cancers is still in its initial phases with only a limited amount of clinical data available, the field is advancing rapidly, incorporating novel technologies to mitigate potential toxicities and enhance antigen-directed tumor eradication.

The Effectiveness of Atezolizumab in Metastatic Large Cell Neuroendocrine Carcinoma of the Lungs: Insights from the LANCE Pilot Study.

BACKGROUND: Large cell neuroendocrine carcinoma (LCNEC) presents significant treatment challenges due to its rarity and limited therapeutic options. The LANCE study was designed to explore the survival benefits of incorporating atezolizumab in chemotherapy for metastatic LCNEC. METHODS: In this non-randomized study, patients with metastatic LCNEC were prospectively enrolled and assigned to receive either standard chemotherapy plus atezolizumab followed by maintenance with atezolizumab or standard chemotherapy alone. The primary outcomes measured were 12- and 24-month survival rates, progression-free survival (PFS), and overall survival (OS) between the two groups. RESULTS: Of the 22 patients screened, 17 met the inclusion criteria and received either atezolizumab plus platinum-based chemotherapy (n = 10) or chemotherapy alone (n = 7). After a median follow-up of 23.3 months, the 12-month survival rate was 57.1% (95% CI: 32.6-100%) and 14.3% (95% CI: 2.33-87.7%) for the atezolizumab and the chemotherapy-only groups, respectively. The survival benefit for the atezolizumab group was sustained at 24 months (45.7% vs. 14.3%). Overall survival was significantly higher for the atezolizumab group, and PFS was non-significantly associated with the addition of atezolizumab (log-rank p = 0.04 and 0.05, respectively). CONCLUSIONS: This pilot study suggests that the addition of atezolizumab to standard platinum-based chemotherapy may provide a substantial survival benefit compared with chemotherapy alone in the first-line treatment of metastatic LCNEC.

A RAND/UCLA-Modified VAS Study on Telemedicine, Telehealth, and Virtual Care in Daily Clinical Practice of Vascular Medicine.

Background: Telemedicine is increasingly used in several fields of healthcare, including vascular medicine. This study aimed to investigate the views of experts and propose clinical practice recommendations on the possible applications of telemedicine in vascular medicine. Methods: A clinical guidance group proposed a set of 67 clinical practice recommendations based on the synthesis of current evidence and expert opinion. The Telemedicine Vascular Medicine Working Group included 32 experts from Europe evaluating the appropriateness of each clinical practice recommendation based on published RAND/UCLA methodology in two rounds. Results: In the first round, 60.9% of clinical practice recommendations were rated as appropriate, 35.9% as uncertain, and 3.1% as inappropriate. The strongest agreement (a median value of 10) was reached on statements regarding the usefulness of telemedicine during the 2019 coronavirus disease (COVID-19) pandemic, its usefulness for geographical areas that are difficult to access, and the superiority of video calls compared to phone calls only. The lowest degree of agreement (a median value of 2) was reported on statements regarding the utility of telemedicine being limited to the COVID-19 pandemic and regarding the applicability of teleconsultation in the diagnosis and management of abdominal aortic aneurysm. In the second round, 11 statements were re-evaluated to reduce variability. Conclusions: This study highlights the levels of agreement and the points that raise concern on the use of telemedicine in vascular medicine. It emphasizes the need for further clarification on various issues, including infrastructure, logistics, and legislation.

Osimertinib Resistance: Molecular Mechanisms and Emerging Treatment Options.

The development of tyrosine kinase inhibitors (TKIs) targeting the mutant epidermal growth factor receptor (EGFR) protein initiated the success story of targeted therapies in non-small-cell lung cancer (NSCLC). Osimertinib, a third-generation EGFR-TKI, is currently indicated as first-line therapy in patients with NSCLC with sensitizing EGFR mutations, as second-line therapy in patients who present the resistance-associated mutation T790M after treatment with previous EGFR-TKIs, and as adjuvant therapy for patients with early stage resected NSCLC, harboring EGFR mutations. Despite durable responses in patients with advanced NSCLC, resistance to osimertinib, similar to other targeted therapies, inevitably develops. Understanding the mechanisms of resistance, including both EGFR-dependent and -independent molecular pathways, as well as their therapeutic potential, represents an unmet need in thoracic oncology. Interestingly, differential resistance mechanisms develop when osimertinib is administered in a first-line versus second-line setting, indicating the importance of selection pressure and clonal evolution of tumor cells. Standard therapeutic approaches after progression to osimertinib include other targeted therapies, when a targetable genetic alteration is detected, and cytotoxic chemotherapy with or without antiangiogenic and immunotherapeutic agents. Deciphering the when and how to use immunotherapeutic agents in EGFR-positive NSCLC is a current challenge in clinical lung cancer research. Emerging treatment options after progression to osimertinib involve combinations of different therapeutic approaches and novel EGFR-TKI inhibitors. Research should also be focused on the standardization of liquid biopsies in order to facilitate the monitoring of molecular alterations after progression to osimertinib.

An overview of the role of telomeres and telomerase in pre­neoplastic lesions (Review).

Telomeres are tandem repeats of DNA sequences protecting the end of linear chromosomes. Replicative senescence due to telomere attrition is considered a tumor-preventing mechanism in differentiated somatic cells. However, telomere shortening is associated with genome instability and several disease entities. During carcinogenesis, the development of a telomere maintenance mechanism, predominately through the activation of the telomerase enzyme, represents a hallmark of cancer, since it enables cancer cells to avert senescence and divide indefinitely. Although research of the involvement of telomeres and telomerase in various malignant neoplasms has gained a large amount of interest, the timing and relevance of their role in pre-neoplastic lesions remain to be determined. The present narrative review aims to summarize the evidence regarding the role of telomeres and telomerase in pre-neoplasia across different types of tissues.

BRAF/MEK inhibition in NSCLC: mechanisms of resistance and how to overcome it.

Targeted therapy for oncogenic genetic alterations has changed the treatment paradigm of advanced non-small cell lung cancer (NSCLC). Mutations in the BRAF gene are detected in approximately 4% of patients and result in hyper-activation of the MAPK pathway, leading to uncontrolled cellular proliferation. Inhibition of BRAF and its downstream effector MEK constitutes a therapeutic strategy for a subset of patients with NSCLC and is associated with clinical benefit. Unfortunately, the majority of patients will develop disease progression within 1 year. Preclinical and clinical evidence suggests that resistance mechanisms involve the restoration of MAPK signaling which becomes inhibition-independent due to upstream or downstream alterations, and the activation of bypass pathways, such as the PI3/AKT/mTOR pathway. Future research should be directed to deciphering the mechanisms of cancer cells' oncogenic dependence, understanding the tissue-specific mechanisms of BRAF-mutant tumors, and optimizing treatment strategies after progression on BRAF and MEK inhibition.

Emerging therapies in thymic epithelial tumors (Review).

Thymic epithelial tumors (TETs), including thymomas and thymic carcinomas, are rare malignancies arising from the thymus gland. The optimal management requires a multidisciplinary approach. Standard first-line systemic treatment involves cytotoxic chemotherapeutic regimens; however, alternative options for systemic treatment are required. Current research focuses on the unique profile of immune-related pathogenic mechanisms of TETs, involving an overlap with certain autoimmune phenotypes, as well as on determining the landscape of oncogenic molecular alterations and the role of tumor angiogenesis. The aim of the present review is to summarize the current clinical investigation on immunotherapy and targeted agents in the management of TETs. Regarding immune checkpoint inhibitors, efficacy results are promising in certain subsets of patients; however, caution is required concerning their toxicity. Anti-angiogenic agents, mainly potent small-molecule inhibitors, have demonstrated antitumor activity in TETs, whereas other targeted agents, including KIT inhibitors and epigenetic agents, are associated with encouraging, yet still modest results for unselected populations, in the absence of predictive biomarkers. Future research should focus on identifying predictive biomarkers for patients with TETs, and should implement multicenter collaborations and appropriate clinical trials tailored for rare tumor types.

Lung microbiome: an emerging player in lung cancer pathogenesis and progression.

The microbiome of the lungs, although until recently neglected, is now emerging as a potential contributor to chronic lung diseases, including cancer. Preclinical evidence suggests that the microbial burden of the lungs shapes the host immunity mechanisms and affects local antitumor immune responses. Studies of cohorts of patients with lung cancer reveal that different microbiome profiles are detected in patients with lung cancer compared to controls. In addition, an association between differential lung microbiome composition and distinct responses to immunotherapy has been suggested, yet, with limited data. Scarce evidence exists on the role of the lung microbiome in the development of metastases in the lungs. Interestingly, the lung microbiome is not isolated and interacts with the gut microbiome through a dynamic axis. Future research on the involvement of the lung microbiome in lung cancer pathogenesis and potential therapeutic implications is greatly anticipated.

Estrogen-Receptor-Low-Positive Breast Cancer: Pathological and Clinical Perspectives.

The expression of estrogen receptors (ERs) in breast cancer (BC) represents a strong prognostic and predictive biomarker and directs therapeutic decisions in early and advanced stages. ER-low-positive BC, defined by the immunohistochemical (IHC) expression of ERs from 1% to 9%, constitutes a distinct subset of total BC cases. Guidelines recommend that a low expression of ERs be reported in pathology reports since the benefit of endocrine therapy in patients with ER-low-positive BC is uncertain. Recently, several cohorts, mostly of a retrospective nature, have been published, reporting the clinicopathological characteristics and outcomes of ER-low-positive BC. However, the majority of the data focus on early-stage BC and the use of (neo)adjuvant therapy, and there is a significant lack of data regarding metastatic ER-low-positive BC. Further factors, including tumor heterogeneity as well as the potential loss of ER expression due to endocrine resistance, should be considered. Including patients with ER-low-positive BC in clinical trials for triple-negative breast cancer (TNBC) might improve the understanding of this entity and allow novel therapeutic approaches. The design and conduction of randomized clinical trials regarding this subgroup of patients are greatly anticipated.

Progress and Challenges of Messenger RNA Vaccines in the Therapeutics of NSCLC.

The introduction of immune checkpoint inhibitors in the therapeutics of non-small cell lung cancer (NSCLC) has been a game-changer in the management of patients with lung cancer; however, challenges do exist since a non-negligible subset of patients does not respond to therapy. Various immunotherapeutic anticancer strategies have been increasingly developed in recent years, including monoclonal antibodies, adoptive T-cell therapy, and vaccines. Fueled by their rapid drug development and successful implementation during the COVID-19 pandemic, messenger RNA (mRNA) vaccines represent an emerging therapeutic approach in other fields of medicine, including oncology. Several clinical trials are currently being conducted to assess the safety and efficacy of mRNA vaccines regarding a variety of solid tumors. Combining mRNA vaccines with other immunotherapeutic approaches has also been suggested and is currently under investigation. Although, in the case of NSCLC, the investigation is still in its early stages, the initial results raise the need for clinician awareness of these promising therapies. To this end, in the present review, we aim to summarize current advances in the development of mRNA vaccines in NSCLC therapeutics and discuss pragmatic challenges regarding their drug development and the different opportunities for implementation.