Mutant p53 upregulates alpha-1 antitrypsin expression and promotes invasion in lung cancer

DNA-delivered monoclonal antibodies targeting the p53 R175H mutant epitope inhibit tumor development in mice

The tumor suppressor p53 is the most common mutated gene in cancer, with the R175H as the most frequent p53 missense mutant. However, there are currently no approved targeted therapies or immunotherapies against mutant p53. Here, we characterized and investigated a monoclonal antibody (mAb) that recognizes the mutant p53-R175H for its affinity, specificity, and activity against tumor cells in vitro. We then delivered DNA plasmids expressing the anti-R175H mAb or a bispecific antibody (BsAb) into mice to evaluate their therapeutic effects. Our results showed that the anti-R175H mAb specifically bound to the p53-R175H antigen with a high affinity and recognized the human mutant p53-R175H antigen expressed on HEK293T or MC38 cells, with no cross-reactivity with wild-type p53. In cultured cells, the anti-R175H mAb showed higher cytotoxicity than the control but did not induce antibody-dependent cellular cytotoxicity. We made a recombinant MC38 mouse cell line (MC38-p53-R175H) that overexpressed the human p53-R175H after knocking out the endogenous mutant p53 alleles. In vivo, administration of the anti-R175H mAb plasmid elicited a robust anti-tumor effect against MC38-p53-R175H in mice. The administration of the anti-R175H BsAb plasmid showed no therapeutic effects, yet potent anti-tumor activity was observed in combination with the anti-PD-1 antibody. These results indicate that targeting specific mutant epitopes using DNA-delivered mAbs or BsAbs presents a form of improved natural immunity derived from tumor-infiltrating B cells and plasma cells against intracellular tumor antigens.

A prime editor mouse to model a broad spectrum of somatic mutations in vivo

Genetically engineered mouse models only capture a small fraction of the genetic lesions that drive human cancer. Current CRISPR-Cas9 models can expand this fraction but are limited by their reliance on error-prone DNA repair. Here we develop a system for in vivo prime editing by encoding a Cre-inducible prime editor in the mouse germline. This model allows rapid, precise engineering of a wide range of mutations in cell lines and organoids derived from primary tissues, including a clinically relevant Kras mutation associated with drug resistance and Trp53 hotspot mutations commonly observed in pancreatic cancer. With this system, we demonstrate somatic prime editing in vivo using lipid nanoparticles, and we model lung and pancreatic cancer through viral delivery of prime editing guide RNAs or orthotopic transplantation of prime-edited organoids. We believe that this approach will accelerate functional studies of cancer-associated mutations and complex genetic combinations that are challenging to construct with traditional models.

Loss of RPA1 Impairs Peripheral T Cell Homeostasis and Exacerbates Inflammatory Damage through Triggering T Cell Necroptosis

The peripheral T cell pool is maintained at dynamic homeostasis through fine-tuning of thymic output and self-renewal of naïve T cells. Lymphopenia or reduced lymphocyte number is implicated in autoimmune diseases, yet little is known about the homeostatic mechanisms. Here, it is reported that the replication protein A1 (RPA1) plays a critical role in T cell homeostasis. Utilizing T cell-specific Rpa1-deficient (Rpa1^fl/fl Cd4-cre) mice, loss of Rpa1 results in lymphopenia through restraining peripheral T cell population and limiting TCR repertoire diversity. Moreover, Rpa1^fl/fl Cd4-cre mice exhibit increased susceptibility to inflammatory diseases, including colitis and hepatitis. Clinical analysis reveals that the expression of RPA1 is reduced in patients with ulcerative colitis or other autoinflammatory diseases. Mechanistically, depletion of RPA1 activates ZBP1-RIPK3 signaling through triggering the genomic DNA leakage into cytosol, consequently resulting in T cell necroptosis. This necroptotic T cell death induced by RPA1 deficiency allows the release of damage-associated molecular patterns (DAMPs), which in turn recruits leukocytes and exacerbates inflammatory response. Reciprocally, chemical or genetic inhibition of necroptosis signaling can ameliorate the Rpa1 deficiency-induced inflammatory damage. The studies thus uncover the importance of RPA1-ZBP1-RIPK3 axis in T cell homeostasis and provide a promising strategy for autoinflammatory disease treatment.

Alpha-1 antitrypsin expression is upregulated in multidrug-resistant cancer cells

Identification of the signature molecular profiles involved in therapy resistance is of vital importance in developing new strategies for treatments and disease monitoring. Protein alpha-1 antitrypsin (AAT, encoded by SERPINA1 gene) is an acute-phase protein, and its high expression has been linked with unfavorable clinical outcome in different types of cancer; however, data on its involvement in therapy resistance are still insufficient. We analyzed SERPINA1 mRNA expression in three different multidrug-resistant (MDR) cell lines-U87-TxR, NCI-H460/R, and DLD1-TxR-and in U87 cells grown in alginate microfibers as a 3D cellular model of glioblastoma. Expression of IL-6 as a major modulator of SERPINA1 was also analyzed. Additionally, AAT protein expression in MDR cells was analyzed by immunofluorescence. SERPINA1 gene expression and AAT protein expression were significantly upregulated in all the tested MDR cell lines compared with their sensitive counterparts. Moreover, SERPINA1 was significantly upregulated in 3D models of glioblastoma, previously found to have upregulated drug-resistance-related gene expression compared with 2D cells. With the exception of NCI-H460/R, in all cell lines as well as in a 3D model of U87 cells, increase in SERPINA1 expression correlated with the increase in IL-6 expression. Our results indicate that AAT could be utilized as a biomarker of therapy resistance in cancer; however, further studies are needed to elucidate the mechanisms driving AAT upregulation in therapy resistance and its biological significance in this process.

diaPASEF Proteomics and Feature Selection for the Description of Sputum Proteome Profiles in a Cohort of Different Subtypes of Lung Cancer Patients and Controls

The high mortality, the presence of an initial asymptomatic stage and the fact that diagnosis in early stages reduces mortality justify the implementation of screening programs in the populations at risk of lung cancer. It is imperative to develop less aggressive methods that can complement existing diagnosis technologies. In this study, we aimed to identify lung cancer protein biomarkers and pathways affected in sputum samples, using the recently developed diaPASEF mass spectrometry (MS) acquisition mode. The sputum proteome of lung cancer cases and controls was analyzed through nano-HPLC–MS using the diaPASEF mode. For functional analysis, the results from differential expression analysis were further analyzed in the STRING platform, and feature selection was performed using sparse partial least squares discriminant analysis (sPLS-DA). Our results showed an activation of inflammation, with an alteration of pathways and processes related to acute-phase, complement, and immune responses. The resulting sPLS-DA model separated between case and control groups with high levels of sensitivity and specificity. In conclusion, we showed how new-generation proteomics can be used to detect potential biomarkers in sputum samples, and ultimately to discriminate patients from controls and even to help to differentiate between different cancer subtypes.

Alpha-1 antitrypsin deficiency and risk of lung cancer in never-smokers: a multicentre case–control study

Background

Lung cancer (LC) is the most commonly diagnosed cancer and the leading cause of cancer-related death in both sexes worldwide. Although the principal risk factor in the western world is tobacco smoking, genetic factors, including alpha-1 antitrypsin deficiency (AATD), have been associated with increased risk. This study is the continuation of an earlier one published by the same group in 2015, aimed at analysing risk of LC in never-smokers, associated with carriers of the AATD genotype.

Methods

A multicentre case–control study was conducted in Spain across the period January 2011 to August 2019. Cases were non-smokers diagnosed with LC, and controls were composed of never-smoking individuals undergoing major non-cancer-related surgery. Data were collected on epidemiological characteristics, exposure to environmental tobacco smoke (ETS), residential radon levels, and alpha-1 antitrypsin (AAT) genotype.

Results

The study included 457 cases (42%) and 631 controls (58%), with a predominance of women (72,8%). The most frequent histological type was adenocarcinoma (77.5%), followed by squamous cell carcinoma (7.7%). No association of risk of LC was found with the status of AATD genotype carrier, both overall and broken down by age, sex, or exposure to ETS.

Conclusions

No risk association was found between being a carrier of an AAT deficiency genotype and LC among never-smokers. In order to establish the existence of an association, we consider it important to expand the studies in never smokers in different geographical areas as well as to include patients with previous chronic lung diseases to assess if it influences the risk.

High DSCC1 Level Predicts Poor Prognosis of Lung Adenocarcinoma

Purpose

To evaluate the role of DSCC1 in LUAD.

Patients and Methods

Based on TCGA and GTEx, the Wilcoxon rank-sum test was used to compare the expression differences of DSCC1 between the normal samples of GTEx combined TCGA and the unpaired tumor samples of TCGA, and to compare DSCC1 expression values between tumor tissues and paired normal LUAD tissues in the TCGA cohort. Kruskal–Wallis rank-sum test, Wilcoxon rank-sum test, and logistics regression were used to compare the relationship between the expression of DSCC1 and the clinicopathological parameters. The biological function of DSCC1 was annotated by GSEA and ssGSEA, while Kaplan–Meier and Cox regression analysis were used to evaluate the prognostic value of DSCC1. Furthermore, the time-dependent ROC curve was used to analyze the diagnostic efficacy of DSCC1 in LUAD.

Results

We downloaded the RNA-Seq data of 513 LUAD cases. The expression of DSCC1 was significantly correlated with T stage (OR = 1.04(1.02–1.07), P = 0.002), pathological stage (OR=1.03 (1.01–1.05), P = 0.008) and TP53 status (OR=1.10 (1.07–1.14), P < 0.001). The high expression of DSCC1 was significantly correlated with DSS (HR=1.56 (1.07–2.26), P = 0.021) and OS (HR=1.53 (1.14–2.05), P = 0.004). Moreover, ROC curve analysis (AUC=0.845, CI (0.820-0.870)) indicated DSCC1 as a potential diagnostic molecule for LUAD. In the group with high DSCC1 expression phenotype, down-regulation of EGFR signal, reduction of IL-6 deprivation, cell cycle, and p53 signal pathway were significantly abundant. Spearman correlation analysis showed that the expression of DSCC1 was positively correlated with the infiltration of Th2 cells, T Helper cells.

Conclusion

Our results suggest that DSCC1 may be an important biomarker for the treatment of LUAD.

Discovery of bladder cancer biomarkers in paired pre- and postoperative urine samples

Background

Bladder cancer (BC), a common cancer of the urinary system, has a low mortality but an extremely high recurrence rate. Patients who have undergone initial surgical treatment often undergo frequent prognostic examinations with a substantial burden of discomfort and costs. Urine samples can reflect early disease processes in the urinary system and may be an excellent source of biomarkers.

Methods

In the present study, we used the liquid chromatography with tandem mass spectrometry (LC-MS/MS) to perform proteomic analysis of pre- and postoperative urine samples from patients with stage III BC to identify biomarkers of cancer prognosis. Candidate biomarkers from proteomic analysis were simultaneously validated using western blotting in an independent cohort and immunohistochemical (IHC) staining, combined with gene expression data of BC samples in The Cancer Genome Atlas (TCGA).

Results

The comparison of pre- and postoperative urine samples from the same patients led to the discovery of several significantly differentially expressed proteins, whose functions could be closely related to the occurrence and development of BC. We confirmed a representative group of candidate biomarker molecules, such as cadherin-related family member 2 (CDHR2), heat shock protein beta-1 (HSP27), and heterogeneous nuclear ribonucleoproteins A2/B1 (HNRNPA2B1).

Conclusions

The candidate biomarker molecules can distinguish between pre- and postoperative urine samples, and alterations in their expression levels are significantly associated with recurrence rates in patients with BC. Therefore, these molecules may become useful biomarkers for the monitoring and prognosis of BC.

The Role of p53 in Progression of Cutaneous Squamous Cell Carcinoma

Skin cancers are the most common types of cancer worldwide, and their incidence is increasing. Melanoma, basal cell carcinoma (BCC), and cutaneous squamous cell carcinoma (cSCC) are the three major types of skin cancer. Melanoma originates from melanocytes, whereas BCC and cSCC originate from epidermal keratinocytes and are therefore called keratinocyte carcinomas. Chronic exposure to ultraviolet radiation (UVR) is a common risk factor for skin cancers, but they differ with respect to oncogenic mutational profiles and alterations in cellular signaling pathways. cSCC is the most common metastatic skin cancer, and it is associated with poor prognosis in the advanced stage. An important early event in cSCC development is mutation of the TP53 gene and inactivation of the tumor suppressor function of the tumor protein 53 gene (TP53) in epidermal keratinocytes, which then leads to accumulation of additional oncogenic mutations. Additional genomic and proteomic alterations are required for the progression of premalignant lesion, actinic keratosis, to invasive and metastatic cSCC. Recently, the role of p53 in the invasion of cSCC has also been elucidated. In this review, the role of p53 in the progression of cSCC and as potential new therapeutic target for cSCC will be discussed.

Identification and characterization of non-small cell lung cancer associated sialoglycoproteins

Aberrantly sialylated cellular glycoconjugates were found to be involved in different processes during tumorigenesis. Such alteration was also noted in case of lung cancer, an important cause of cancer-related death throughout the world. Thus, study on lung cancer associated sialoglycoproteins is of paramount relevance to have a deeper insight into the mechanism of the disease pathogenesis. In the present study, sialic acid specific lectin (Maackia amurensis agglutinin and Sambcus nigra agglutinin)-based affinity chromatography followed by 2D-PAGE and MALDI-TOF/TOF mass spectrometric analysis were done to explore the disease-associated serum proteins of squamous cell carcinoma and adenocarcinoma [the major two subtypes of NSCLC (non-small cell lung carcinoma)] patients. Among seven identified proteins, α1-antitrypsin and haptoglobin-β were preferred for further studies. These two proteins were characterized as the disease associated serum-sialoglycoproteins of NSCLC-patients by western immunoblotting using each lectin specific inhibitor. The presence of these sialoglycoproteins was found on NSCLC cell lines (NCI-H520 & A549) by confocal microscopy. Both these proteins were also present in tissue samples of NSCLC origin and involved in proliferation, invasion and migration of NSCLC cells. Our findings suggest that α1-antitrypsin and haptoglobin-β may be the disease-associated sialoglycoproteins in NSCLC, which seem to be involved in disease progression. SIGNIFICANCE: Our contribution regarding the identification of the NSCLC associated sialoglycoproteins may provide a new vision towards the development of clinically useful newer strategies for the treatment of this disease.

The Role of p53 Dysfunction in Colorectal Cancer and Its Implication for Therapy

Colorectal cancer (CRC) is one of the most common and fatal cancers worldwide. The carcinogenesis of CRC is based on a stepwise accumulation of mutations, leading either to an activation of oncogenes or a deactivation of suppressor genes. The loss of genetic stability triggers activation of proto-oncogenes (e.g., KRAS) and inactivation of tumor suppression genes, namely TP53 and APC, which together drive the transition from adenoma to adenocarcinoma. On the one hand, p53 mutations confer resistance to classical chemotherapy but, on the other hand, they open the door for immunotherapy, as p53-mutated tumors are rich in neoantigens. Aberrant function of the TP53 gene product, p53, also affects stromal and non-stromal cells in the tumor microenvironment. Cancer-associated fibroblasts together with other immunosuppressive cells become valuable assets for the tumor by p53-mediated tumor signaling. In this review, we address the manifold implications of p53 mutations in CRC regarding therapy, treatment response and personalized medicine.

Mutant p53 Drives Cancer Metastasis via RCP-Mediated Hsp90α Secretion

Mutant p53 (mutp53) loses its tumor suppressor properties but gains oncogenic functions of driving malignancy. However, it remains largely unknown how mutp53 drives cancer metastasis. Here, we show that wild-type p53 (WTp53) suppresses the secretion of heat shock protein 90-alpha (Hsp90α), whereas mutp53 enhances Hsp90α vesicular trafficking and exosome-mediated secretion. Long-term delivery of an antibody that blocks extracellular Hsp90α (eHsp90α) function extends the survival of p53^-/- mice and attenuates the invasiveness of p53 mutant tumors. Furthermore, mass spectrometry and functional analysis identified a critical role for Rab coupling protein (RCP) in mutp53-induced Hsp90α secretion. RCP knockdown decreases eHsp90α levels and inhibits malignant progression. Notably, recombinant Hsp90α re-introduction markedly rescues the impaired migration and invasion abilities caused by RCP depletion. Taken together, these findings elucidate the molecular mechanisms by which mutp53 executes oncogenic activities via its downstream RCP-mediated Hsp90α secretion and a strategy to treat human cancers expressing mutp53 proteins.

Auranofin reveals therapeutic anticancer potential by triggering distinct molecular cell death mechanisms and innate immunity in mutant p53 non-small cell lung cancer

Auranofin (AF) is an FDA-approved antirheumatic drug with anticancer properties that acts as a thioredoxin reductase 1 (TrxR) inhibitor. The exact mechanisms through which AF targets cancer cells remain elusive. To shed light on the mode of action, this study provides an in-depth analysis on the molecular mechanisms and immunogenicity of AF-mediated cytotoxicity in the non-small cell lung cancer (NSCLC) cell line NCI–H1299 (p53 Null) and its two isogenic derivates with mutant p53 R175H or R273H accumulation.

TrxR is highly expressed in a panel of 72 NSCLC patients, making it a valid druggable target in NSCLC for AF. The presence of mutant p53 overexpression was identified as an important sensitizer for AF in (isogenic) NSCLC cells as it was correlated with reduced thioredoxin (Trx) levels in vitro. Transcriptome analysis revealed dysregulation of genes involved in oxidative stress response, DNA damage, granzyme A (GZMA) signaling and ferroptosis. Although functionally AF appeared a potent inhibitor of GPX4 in all NCI–H1299 cell lines, the induction of lipid peroxidation and consequently ferroptosis was limited to the p53 R273H expressing cells. In the p53 R175H cells, AF mainly induced large-scale DNA damage and replication stress, leading to the induction of apoptotic cell death rather than ferroptosis. Importantly, all cell death types were immunogenic since the release of danger signals (ecto-calreticulin, ATP and HMGB1) and dendritic cell maturation occurred irrespective of (mutant) p53 expression. Finally, we show that AF sensitized cancer cells to caspase-independent natural killer cell-mediated killing by downregulation of several key targets of GZMA.

Our data provides novel insights on AF as a potent, clinically available, off-patent cancer drug by targeting mutant p53 cancer cells through distinct cell death mechanisms (apoptosis and ferroptosis). In addition, AF improves the innate immune response at both cytostatic (natural killer cell-mediated killing) and cytotoxic concentrations (dendritic cell maturation).

Amplifying Tumor-Stroma Communication: An Emerging Oncogenic Function of Mutant p53

TP53 mutations are widespread in human cancers. An expanding body of evidence highlights that, in addition to their manifold cell-intrinsic activities boosting tumor progression, missense p53 mutants enhance the ability of tumor cells to communicate amongst themselves and with the tumor stroma, by affecting both the quality and the quantity of the cancer secretome. In this review, we summarize recent literature demonstrating that mutant p53 enhances the production of growth and angiogenic factors, inflammatory cytokines and chemokines, modulates biochemical and biomechanical properties of the extracellular matrix, reprograms the cell trafficking machinery to enhance secretion and promote recycling of membrane proteins, and affects exosome composition. All these activities contribute to the release of a promalignant secretome with both local and systemic effects, that is key to the ability of mutant p53 to fuel tumor growth and enable metastatic competence. A precise knowledge of the molecular mechanisms underlying the interplay between mutant p53 and the microenvironment is expected to unveil non-invasive biomarkers and actionable targets to blunt tumor aggressiveness.

Mutational drivers of cancer cell migration and invasion

Genomic instability and mutations underlie the hallmarks of cancer-genetic alterations determine cancer cell fate by affecting cell proliferation, apoptosis and immune response, and increasing data show that mutations are involved in metastasis, a crucial event in cancer progression and a life-threatening problem in cancer patients. Invasion is the first step in the metastatic cascade, when tumour cells acquire the ability to move, penetrate into the surrounding tissue and enter lymphatic and blood vessels in order to disseminate. A role for genetic alterations in invasion is not universally accepted, with sceptics arguing that cellular motility is related only to external factors such as hypoxia, chemoattractants and the rigidity of the extracellular matrix. However, increasing evidence shows that mutations might trigger and accelerate the migration and invasion of different types of cancer cells. In this review, we summarise data from published literature on the effect of chromosomal instability and genetic mutations on cancer cell migration and invasion.

Molecular crosstalk between cancer and neurodegenerative diseases

The progression of cancers and neurodegenerative disorders is largely defined by a set of molecular determinants that are either complementarily deregulated, or share remarkably overlapping functional pathways. A large number of such molecules have been demonstrated to be involved in the progression of both diseases. In this review, we particularly discuss our current knowledge on p53, cyclin D, cyclin E, cyclin F, Pin1 and protein phosphatase 2A, and their implications in the shared or distinct pathways that lead to cancers or neurodegenerative diseases. In addition, we focus on the inter-dependent regulation of brain cancers and neurodegeneration, mediated by intercellular communication between tumor and neuronal cells in the brain through the extracellular microenvironment. Finally, we shed light on the therapeutic perspectives for the treatment of both cancer and neurodegenerative disorders.

Alpha-1 Antitrypsin Induces Epithelial-to-Mesenchymal Transition, Endothelial-to-Mesenchymal Transition, and Drug Resistance in Lung Cancer Cells

Purpose

Alpha-1 antitrypsin (A1AT) is a secreted protein that plays an important role in various diseases. However, the role of A1AT in non-small cell lung cancer is obscure.

Materials and Methods

A1AT expression in non-small cell lung cancer was analyzed using quantitative reverse transcription PCR, Western blotting (WB), immunohistochemistry (IHC), and ELISA. WB and IF were used to analyze markers of epithelial-to-mesenchymal transition (EMT), EndoMT, and cancer stem cell (CSC). Transwell and cell wound healing assays were used to analyze migration and invasion abilities. Colony formation and CCK-8 assays were used to analyze cell proliferation following cisplatin treatment.

Results

A1AT expression was higher in lung cancer samples than in normal tissues and the increased expression was correlated with poor overall survival of patients. In vitro experiments showed that A1AT overexpressed by plasmid transfection significantly promoted migration, invasion, EMT, EndoMT, stemness, and colony formation in lung cancer cell lines, as opposed to A1AT downregulation by siRNA transfection, which significantly inhibited all these variables.

Conclusion

A1AT is a novel therapeutic target and might be associated with tumor metastasis in lung carcinoma.

Identification of a Seven-lncRNA Immune Risk Signature and Construction of a Predictive Nomogram for Lung Adenocarcinoma

Background

The incidence of lung cancer is the highest of all cancers, and it has the highest death rate. Lung adenocarcinoma (LUAD) is a major type of lung cancer. This study is aimed at identifying the prognostic value of immune-related long noncoding RNAs (lncRNAs) in LUAD.

Materials and Methods

Gene expression profiles and the corresponding clinicopathological features of LUAD patients were obtained from The Cancer Genome Atlas (TCGA). The least absolute shrinkage and selection operator (LASSO) Cox regression algorithm was performed on the prognostic immune-related lncRNAs to calculate the risk scores, and a risk signature was constructed. Survival analysis was performed to assess the prognostic value of the risk signature. A nomogram was also constructed based on the clinicopathological features and risk signature.

Results

A total of 437 LUAD patients with gene expression data and clinicopathological features were obtained in this study, which was considered the combination set. They were randomly and equally divided into a training set and a validation set. Seven immune-related lncRNAs (AC092794.1, AL034397.3, AC069023.1, AP000695.1, AC091057.1, HLA-DQB1-AS1, and HSPC324) were identified and used to construct a risk signature. The patients were divided into the low- and high-risk groups based on the median risk score of -0.04074. Survival analysis suggested that patients in the low-risk group had a longer overall survival (OS) than those in the high-risk group (p = 1.478e − 02). A nomogram was built that could predict the 1-, 3-, and 5-year survival rates of LUAD patients (C-index of the nomogram was 0.755, and the AUCs for the 1-, 3-, and 5-year survivals were 0.826, 0.719, and 0.724, respectively). The validation and combination sets confirmed these results.

Conclusion

Our study identified seven novel immune-related lncRNAs and generated a risk signature, as well as a nomogram, that could predict the prognosis of LUAD patients.

Mechanisms behind Retinal Ganglion Cell Loss in Diabetes and Therapeutic Approach

Diabetes produces several changes in the body triggered by high glycemia. Some of these changes include altered metabolism, structural changes in blood vessels and chronic inflammation. The eye and particularly the retinal ganglion cells (RGCs) are not spared, and the changes eventually lead to cell loss and visual function impairment. Understanding the mechanisms resulting in RGC damage and loss from diabetic retinopathy is essential to find an effective treatment. This review focuses mainly on the signaling pathways and molecules involved in RGC loss and the potential therapeutic approaches for the prevention of this cell death. Throughout the manuscript it became evident that multiple factors of different kind are responsible for RGC damage. This shows that new therapeutic agents targeting several factors at the same time are needed. Alpha-1 antitrypsin as an anti-inflammatory agent may become a suitable option for the treatment of RGC loss because of its beneficial interaction with several signaling pathways involved in RGC injury and inflammation. In conclusion, alpha-1 antitrypsin may become a potential therapeutic agent for the treatment of RGC loss and processes behind diabetic retinopathy.

Gain-of-Function Mutations in p53 in Cancer Invasiveness and Metastasis

Forty years of research has proven beyond any doubt that p53 is a key regulator of many aspects of cellular physiology. It is best known for its tumor suppressor function, but it is also a regulator of processes important for maintenance of homeostasis and stress response. Its activity is generally antiproliferative and when the cell is damaged beyond repair or intensely stressed the p53 protein contributes to apoptosis. Given its key role in preventing cancer it is no wonder that it is the most frequently mutated gene in human cancer. Surprisingly, a subset of missense mutations occurring in p53 (gain-of-function) cause it to lose its suppressor activity and acquire new functionalities that turn the tumor suppressor protein into an oncoprotein. A solid body of evidence exists demonstrating increased malignancy of cancers with mutated p53 in all aspects considered “hallmarks of cancer”. In this review, we summarize current findings concerning the cellular processes altered by gain-of-function mutations in p53 and their influence on cancer invasiveness and metastasis. We also present the variety of molecular mechanisms regulating these processes, including microRNA, direct transcriptional regulation, protein–protein interactions, and more.

p53's Extended Reach: The Mutant p53 Secretome

p53 suppresses tumorigenesis by activating a plethora of effector pathways. While most of these operate primarily inside of cells to limit proliferation and survival of incipient cancer cells, many extend to the extracellular space. In particular, p53 controls expression and secretion of numerous extracellular factors that are either soluble or contained within extracellular vesicles such as exosomes. As part of the cellular secretome, they execute key roles in cell-cell communication and extracellular matrix remodeling. Mutations in the p53-encoding TP53 gene are the most frequent genetic alterations in cancer cells, and therefore, have profound impact on the composition of the tumor cell secretome. In this review, we discuss how the loss or dominant-negative inhibition of wild-type p53 in concert with a gain of neomorphic properties observed for many mutant p53 proteins, shapes a tumor cell secretome that creates a supportive microenvironment at the primary tumor site and primes niches in distant organs for future metastatic colonization.

Elevated Expression of LYPD3 Is Associated with Lung Adenocarcinoma Carcinogenesis and Poor Prognosis

Aberrant expression of LYPD3 plays an oncogenic role in several types of cancer. However, the functions of LYPD3 in lung adenocarcinoma (LUAD) remain unclear. Here, we investigated the regulatory function, clinical value, and prognostic significance of LYPD3 in LUAD patients. The gene expression and DNA methylation data of LUAD tumor and paracancerous tissues were obtained from The Cancer Genome Atlas (TCGA) database. The association between LYPD3 expression and clinicopathological variables was analyzed. The results showed that LYPD3 was highly expressed in LUAD tumor compared with paracancerous tissues, which was positively correlated with the race (p = 0.0448), tumor stage (p = 0.0191), and survival status (p < 0.001). Furthermore, the expression of LYPD3 was able to be regulated by the methylation in LYPD3 promoter region, which was positively associated with the overall survival. Furthermore, we explored the related pathways through which LYPD3 affects the pathogenesis and prognosis of LUAD by gene set enrichment analysis, and found that LYPD3 might affect the clinical manifestations of LUAD by regulating the P53 signaling pathway. In the future, we would focus on exploring the molecular mechanism of LYPD3 in the regulation of the occurrence and development of LUAD to provide a research basis for the screening of methylation markers related to the treatment and prognosis.

The Diverse Functions of Mutant 53, Its Family Members and Isoforms in Cancer

The p53 family of proteins has grown substantially over the last 40 years. It started with p53, then p63, p73, isoforms and mutants of these proteins. The function of p53 as a tumour suppressor has been thoroughly investigated, but the functions of all isoforms and mutants and the interplay between them are still poorly understood. Mutant p53 proteins lose p53 function, display dominant-negative (DN) activity and display gain-of-function (GOF) to varying degrees. GOF was originally attributed to mutant p53′s inhibitory function over the p53 family members p63 and p73. It has become apparent that this is not the only way in which mutant p53 operates as a large number of transcription factors that are not related to p53 are activated on mutant p53 binding. This raises the question to what extent mutant p53 binding to p63 and p73 plays a role in mutant p53 GOF. In this review, we discuss the literature around the interaction between mutant p53 and family members, including other binding partners, the functional consequences and potential therapeutics.

Clinical Significance of SERPINA1 Gene and Its Encoded Alpha1-antitrypsin Protein in NSCLC

High expression of SERPINA1 gene encoding acute phase protein, alpha1-antitrypsin (AAT), is associated with various tumors. We sought to examine the significance of SERPINA1 and AAT protein in non-small-cell lung cancer (NSCLC) patients and NSCLC cell lines. Tumor and adjacent non-tumor lung tissues and serum samples from 351 NSCLC patients were analyzed for SERPINA1 expression and AAT protein levels. We also studied the impact of SERPINA1 expression and AAT protein on H1975 and H661 cell behavior, in vitro. Lower SERPINA1 expression in tumor but higher in adjacent non-tumor lung tissues (n = 351, p = 0.016) as well as higher serum levels of AAT protein (n = 170, p = 0.033) were associated with worse survival rates. Specifically, in NSCLC stage III patients, higher blood AAT levels (>2.66 mg/mL) correlated with a poor survival (p = 0.002). Intriguingly, levels of serum AAT do not correlate with levels of C-reactive protein, neutrophils-to-leukocyte ratio, and do not correlate with SERPINA1 expression or AAT staining in the tumor tissue. Additional experiments in vitro revealed that external AAT and/or overexpressed SERPINA1 gene significantly improve cancer cell migration, colony formation and resistance to apoptosis. SERPINA1 gene and AAT protein play an active role in the pathogenesis of lung cancer and not just reflect inflammatory reaction related to cancer development.

Fine Mapping in Chromosome 3q28 Identified Two Variants Associated with Lung Cancer Risk in Asian Population

Genome-wide association studies (GWASs) have consistently identified chromosome 3q28 as a lung cancer susceptibility region. To further characterize the potential genetic mechanism of the variants in this region, we conducted a fine-mapping study on chromosome 3q28 region. We performed a target resequencing in 200 lung cancer cases and 300 controls in the screening and followed by validation in multi-ethnic lung cancer GWASs with 12,843 cases and 12,639 controls. For our identified novel variants, we conducted expression quantitative trait loci (eQTL) analysis to reveal the potential target genes. Two susceptibility variants were identified (rs4396880: G>A, OR = 0.35, 95%CI: 0.20-0.62, P = 3.01×10^-4; and rs3856776: C>T, OR = 2.05, 95%CI: 1.32-3.18, P = 1.49×10^-3) and further supported in Asian population (rs4396880: OR = 0.88, P = 7.43×10^-6; and rs3856776: OR =1.17, P = 1.64×10^-4). The eQTL analysis showed the A allele of rs4396880 was significantly associated with higher mRNA expression of TP63 (P = 1.70×10^-4) in lung tissues, while rs3856776 showed significant association with the expression of LEPREL1-AS1 (P = 6.90×10^-3), which was the antisense RNA of LEPREL1 and could suppress the translation of LEPREL1. Notably, LEPREL1 was aberrantly downregulated (P = 2.54×10^-18) in lung tumor tissues based on TCGA database. In conclusion, this is the first fine-mapping analysis of 3q28 region in Han Chinese, and we found two variants associated with lung cancer susceptibility in Asian population. What's more, rs3856776 was newly identified and might modulate lung cancer susceptibility by suppressing the function of LEPREL1.

Fibroblasts in Pancreatic Ductal Adenocarcinoma: Biological Mechanisms and Therapeutic Targets

The desmoplastic reaction of pancreas cancer may begin as a wound healing response to the nascent neoplasm, but it soon creates an insidious shelter that can sustain the growing tumor and rebuff therapy. Among the many cell types subverted by transformed epithelial cells, fibroblasts are recruited and activated to lay a foundation of extracellular matrix proteins and glycosaminoglycans that alter tumor biophysics and signaling. Their near-universal presence in pancreas cancer and ostensible support of disease progression make fibroblasts attractive therapeutic targets. More recently, however, it has also become apparent that diverse subpopulations of fibroblasts with distinct phenotypes and secretomes inhabit the stroma, and that targeted depletion of particular fibroblast subsets could either provide substantial therapeutic benefit or accelerate disease progression. An improved characterization of these fibroblast subtypes, along with their potential relationships to tumor subtypes and mutational repertoires, is needed in order to make anti-fibroblast therapies clinically viable.

FAM111B, a direct target of p53, promotes the malignant process of lung adenocarcinoma

Purpose: Lung adenocarcinoma (LUAD) is a main subtype of lung cancer, which is the leading cause of cancer-related deaths. The five-year survival rates of lung cancer patients are still comparatively low. Therefore, potential therapeutic targets are urgently needed to improve the survival of lung cancer patients. In this study, we identified FAM111B as an oncogene and potential therapeutic target for LUAD.

Methods: The TCGA database and tissue microarray analysis were used to compare the expression of FAM111B in tumor tissue and normal tissues and evaluate the relationship between FAM111B expression and clinical survival. FAM111B was knocked down and overexpressed to observe whether FAM111B could affect the proliferation, migration, cell cycle, and apoptosis of LUAD cells in vivo and in vitro.

Results: FAM111B was highly expressed in tumor tissues compared with normal tissues (P<0.01). LUAD patients with hyper-expression of FAM111B had a lower recurrence-free survival (P<0.01) and shorter overall survival (P<0.01). Knocking down FAM111B inhibited cell proliferation, migration and invasion in vitro and tumor growth in vivo. Silencing FAM111B could arrest LUAD cells at G2/M phase and increase apoptosis. Overexpression of FAM111B promoted the growth of lung cancer cells. FAM111B was identified as a direct target of p53 in existing researches by chip-seq analysis. Bioinformatics analysis predicted that FAM111B could directly bind to BAG3 (BCL2 associated athanogene 3). When FAM111B was down-regulated, both expression of BAG 3 and BCL2 were significantly reduced, whereas decreasing the expression of BAG3 had no effect on FAM111B.

Conclusions: Our study indicated that FAM111B might be an oncogene and potential therapeutic target in LUAD which could be involved in the regulation of tumor cells by p53 signaling pathway and play an important role in the process of cell cycle and apoptosis by influencing the expression of BAG3 and BCL2.

Mutant p53 regulates LPA signaling through lysophosphatidic acid phosphatase type 6

Emerging evidence has indicated that high-grade serous ovarian cancer (HGSOC) originates in the fallopian tube, where the earliest known genetic lesion is the mutation of TP53. In addition to such genetic changes, HGSOC is characterized by altered metabolism, including the production of oncogenic lipids such as lysophosphatidic acid (LPA). To understand the crosstalk between TP53 mutations and LPA signaling, we utilized primary fallopian tube epithelial cells (FTEC) engineered to overexpress mutant p53. We found that gain-of-function (GOF) p53 mutations downregulated the LPA-degrading enzyme lysophosphatidic acid phosphatase type 6 (ACP6), leading to upregulation of focal adhesion signaling in an LPA-dependent manner. Although highly expressed in normal fallopian tube epithelium, ACP6 expression was significantly reduced in ovarian cancer tumors and early in situ lesions. Downregulation of ACP6 in ovarian cancer cells was necessary and sufficient to support HGSOC proliferation, adhesion, migration, and invasion. Using mouse models of metastasis, we established that attenuation of ACP6 expression was associated with increased tumor burden. Conversely, overexpression of ACP6 suppressed invasive behavior. These data identify an involvement of oncogenic p53 mutations in LPA signaling and HGSOC progression through regulation of ACP6 expression.

Tumor cell-specific Serpin A1 expression in vulvar squamous cell carcinoma

Purpose

The two main etiological factors for vulvar squamous cell carcinoma (vSCC) are the vulvar dermatosis lichen sclerosus (LS) and high-risk human papillomavirus (hrHPV). Serpin A1 (α1-antitrypsin) is a serine protease inhibitor, which plays a role in the tumorigenesis of various cancer types. The aim of the study was to evaluate the expressions of Serpin A1 in LS, premalignant vulvar lesions, and vSCC using immunohistochemistry (IHC) and serum analysis, and to compare Serpin A1 stainings to the tumor markers p53 and p16.

Methods

In total, 120 samples from 74 patients were studied with IHC for Serpin A1, p53 and p16: 18 normal vulvar skin, 53 LS, 9 premalignant vulvar lesions (dVIN/HSIL) and 40 vSCC samples. Serum concentrations of Serpin A1 were analyzed from 30 LS, 44 vSCC and 10 control patients. Expressions were compared to clinical data.

Results

Tumor cell-specific Serpin A1 overexpression was detected in 88% of vSCC samples, independent of the etiology. The intensity of Serpin A1 expression was significantly higher in vSCC than in healthy vulvar skin, LS, or premalignant vulvar lesions. Serpin A1 showed an association with p53 positivity. No difference in overall survival was found between Serpin A1-, p53-, or p16-positive vSCC patients. Serum concentrations of Serpin A1 were equal in the LS, vSCC, and control groups.

Conclusion

Tumor cell-specific Serpin A1 overexpression is a potential biomarker in vSCC.

Mutant p53 as a guardian of the cancer cell

Forty years of research have established that the p53 tumor suppressor provides a major barrier to neoplastic transformation and tumor progression by its unique ability to act as an extremely sensitive collector of stress inputs, and to coordinate a complex framework of diverse effector pathways and processes that protect cellular homeostasis and genome stability. Missense mutations in the TP53 gene are extremely widespread in human cancers and give rise to mutant p53 proteins that lose tumor suppressive activities, and some of which exert trans-dominant repression over the wild-type counterpart. Cancer cells acquire selective advantages by retaining mutant forms of the protein, which radically subvert the nature of the p53 pathway by promoting invasion, metastasis and chemoresistance. In this review, we consider available evidence suggesting that mutant p53 proteins can favor cancer cell survival and tumor progression by acting as homeostatic factors that sense and protect cancer cells from transformation-related stress stimuli, including DNA lesions, oxidative and proteotoxic stress, metabolic inbalance, interaction with the tumor microenvironment, and the immune system. These activities of mutant p53 may explain cancer cell addiction to this particular oncogene, and their study may disclose tumor vulnerabilities and synthetic lethalities that could be exploited for hitting tumors bearing missense TP53 mutations.

High scavenger receptor class B type I expression is related to tumor aggressiveness and poor prognosis in lung adenocarcinoma: A STROBE compliant article

Scavenger receptor class B type I (SR-B1) is highly expressed in a variety of cancers, including prostate, breast and ovarian. However, the relationship between SR-B1 and lung adenocarcinoma is unknown. We analyzed the expression of SR-B1 in a well-characterized lung adenocarcinoma tissue microarray by immunohistochemistry, in 90 cancerous and 90 adjacent normal lung tissues. Results showed that the positive expression rate of SR-B1 in cancer tissues (86/90, 96%) was significantly higher than that of adjacent tissues (50/90, 56%) (P < .001). And SR-B1 overexpression in lung adenocarcinoma tissue was significantly higher than that of adjacent normal tissue (P < .001), accounting for 67% of cases. This elevated SR-B1 expression was associated with AJCC stage (P < .001), T stage (P = .012), N stage (P = .002), and lymph node positivity (P < .001). The Kaplan-Meier survival analysis indicated that patients with high SR-B1 expression had a shorter overall survival (P < .001). On the multivariate analysis, SR-B1 was an independent prognostic factor for outcomes after adjustment for other prognostic factors (P = .038). In conclusion, high SR-B1 expression is associated with conventional pathologic parameters that represent tumor aggressiveness and may purport a poor clinical prognosis in lung adenocarcinoma.