Triple negative breast cancer: Shedding light onto the role of pi3k/akt/mtor pathway

Breast cancer is one of the most widespread carcinoma and one of the main causes of cancer-related death worldwide, especially in women aged between 35 and 75 years. Among the different subtypes, triple negative breast cancer (TNBC) is characterized by the total absence of the estrogen-receptor (ER) and progesteron-receptor (PR) expression as well as the lack of human epidermal growth factor receptor 2 (HER2) overexpression or gene amplification. These biological characteristics confer to TNBC a higher aggressiveness and relapse risk along with poorer prognosis compared to other subtypes. Indeed, 5-years survival rate is still low and almost all patients die, despite any adjuvant treatment which at moment represents the heading pharmacological approach. To date, several clinical trials have been designed to investigate the potential role of some molecular markers, such as VEGF, EGFR, Src and mTOR, for targeted treatments in TNBC. In fact, many inhibitors of the PI3K/AKT/mTOR pathway, frequently de-regulated in TNBC, are acquiring a growing interest and several inhibitors are in preclinical development or already in early phase clinical trials. In this Review, we investigated the role of the PI3K/AKT/mTOR pathway in TNBC patients, by summarizing the molecular features that led to the distinction of different histotypes of TNBC. Furthermore, we provided an overview of the inhibition mechanisms of the mTOR and PI3K/AKT signaling pathways, highlighting the importance of integrating biological and clinical data for the development of mTOR inhibitors in order to implement targeted therapies for TNBC patients

Analysis of tissue and circulating microRNA expression during metaplastic transformation of the esophagus

Genetic changes involved in the metaplastic progression from squamous esophageal mucosa toward Barrett's metaplasia and adenocarcinoma are almost unknown. Several evidences suggest that some miRNAs are differentially expressed in Barrett's esophagus (BE) and esophageal adenocarcinoma. Among these, miR-143, miR-145, miR-194, miR-203, miR-205, miR-215 appear to have a key role in metaplasia and neoplastic progression. The aim of this study was to analyze deregulated miRNAs in serum and esophageal mucosal tissue biopsies to identify new biomarkers that could be associated with different stages of esophageal disease. Esophageal mucosal tissue biopsies and blood samples were collected and analyzed for BE diagnosis. Quantitative Real-time PCR was used to compare miRNA expression levels in serum and 60 disease/ normal-paired tissues from 30 patients diagnosed with esophagitis, columnar-lined oesophagus (CLO) or BE. MiRNA expression analysis showed that miR-143, miR-145, miR-194 and miR-215 levels were significantly higher, while miR-203 and miR-205 were lower in BE tissues compared with their corresponding normal tissues. Esophageal mucosa analysis of patients with CLO and esophagitis showed that these miRNAs were similarly deregulated but to a lesser extent keeping the same trend and CLO appeared as intermediate step between esophagitis and BE. Analysis on circulating miRNA levels confirmed that miR-194 and miR-215 were significantly upregulated in both BE and CLO compared to esophagitis, while miR-143 was significantly upregulated only in the Barrett group. These findings suggest that miRNAs may be involved in neoplastic/ metaplastic progression and miRNA analysis might be useful for progression risk prediction as well as for monitoring of BE/CLO patients

UNRAVELLING THE ROLES OF THE NUCLEAR PROTEIN 1 DURING ER-STRESS INDUCTION

Background: NUPR1 was described as a transcriptional factor involved in the regulation of various cellular stress-response genes, playing a crucial role in the condition of the endoplasmic-reticulum (ER) stress, thus emerging as a common molecular factor of different pathologies, obesity, hepatic steatosis, and cancer. In the present work we aim to explore how NUPR1 interacts with some pivotal genes that are the major modulators of the ER stress and metabolic cell functions. In particular we investigated the biochemical and molecular effects arising from the loss of NUPR1 in ER stress physiological conditions. Methods: We used prolonged high fat diet (HFD) feeding to induce ER stress physiological in Nupr1+/+ and Nupr1-/- male mice compared with their respectively normal chow diet (ND) controls. We fed mice with a HFD (60% fat, 20% protein, and 20% carbohydrate) for 10 weeks to promote chronic ER stress condition (Old-HFD group, n=5). An additional group of mice (n=5) was maintained on HFD (60% fat, 20% protein, and 20% carbohydrate) for a longer duration (15 weeks) to distinguish between age-dependent and age-independent effects. Liver were collected for histological and molecular assessments. Western blots and RT-qPCR were performed to assess the expression levels of the major ER-stress response UPR-associated proteins and metabolic genes. Results: We showed the downregulation of the majority of UPR-associated proteins: BIP (p<0.0001 for protein and mRNA), ATF4 (p<0.0001 for mRNA), XBP1 (p<0.0001 for protein and mRNA), CHOP (p<0.0001 for protein and mRNA), GADD34 (p=0.0296 for mRNA) in in-vivo NUPR1-/- compared to NUPR1+/+ 10 weeks HFD mice. Western blot for the major UPR associated proteins in NURP1-/- mice at 15 weeks HFD showed similar expression trends reported at the time-point of 10 weeks. ERDj4 mRNA resulted down-regulated in NUPR1-/- compared to NUPR1+/+ 15 weeks HFD mice (p=0.0032). Among the multiple metabolic genes, we reported a down-regulation of the majority mRNA associated to lipogenesis (SREBP, ACLY, ChREBP) and lipoprotein (APOB, PPAR-alfa, MTTP) in NUPR1-/- compared to NUPR1+/ + HFD mice 15 weeks. Both LCAD and MCAD fatty acid metabolisms mRNA were also downregulated, as consequence of PPAR-alfa deficit. Similarly betaoxidation mRNA ACOX1 and CPT1-alfa, as well as MTC4 and PGK1 were downregulated in NUPR1-/- compared to NUPR1+/ + HFD mice 15 weeks. Conclusion: The results of this work confirm that NUPR1 act downstream of the PERK branch playing a crucial role of NUPR1 in the activation of UPR response in physio-pathological ER stress condition and suggest a potential contribution of NUPR1-mediated ER stress response to the development of liver steatosis.Background: NUPR1 was described as a transcriptional factor involved in the regulation of various cellular stress-response genes, playing a crucial role in the condition of the endoplasmic-reticulum (ER) stress, thus emerging as a common molecular factor of different pathologies, obesity, hepatic steatosis, and cancer. In the present work we aim to explore how NUPR1 interacts with some pivotal genes that are the major modulators of the ER stress and metabolic cell functions. In particular we investigated the biochemical and molecular effects arising from the loss of NUPR1 in ER stress physiological conditions. Methods: We used prolonged high fat diet (HFD) feeding to induce ER stress physiological in Nupr1+/+ and Nupr1-/- male mice compared with their respectively normal chow diet (ND) controls. We fed mice with a HFD (60% fat, 20% protein, and 20% carbohydrate) for 10 weeks to promote chronic ER stress condition (Old-HFD group, n=5). An additional group of mice (n=5) was maintained on HFD (60% fat, 20% protein, and 20% carbohydrate) for a longer duration (15 weeks) to distinguish between age-dependent and age-independent effects. Liver were collected for histological and molecular assessments. Western blots and RT-qPCR were performed to assess the expression levels of the major ER-stress response UPR-associated proteins and metabolic genes. Results: We showed the downregulation of the majority of UPR-associated proteins: BIP (p<0.0001 for protein and mRNA), ATF4 (p<0.0001 for mRNA), XBP1 (p<0.0001 for protein and mRNA), CHOP (p<0.0001 for protein and mRNA), GADD34 (p=0.0296 for mRNA) in in-vivo NUPR1-/- compared to NUPR1+/+ 10 weeks HFD mice. Western blot for the major UPR associated proteins in NURP1-/- mice at 15 weeks HFD showed similar expression trends reported at the time-point of 10 weeks. ERDj4 mRNA resulted down-regulated in NUPR1-/- compared to NUPR1+/+ 15 weeks HFD mice (p=0.0032). Among the multiple metabolic genes, we reported a down-regulation of the majority mRNA associated to lipogenesis (SREBP, ACLY, ChREBP) and lipoprotein (APOB, PPAR-alfa, MTTP) in NUPR1-/- compared to NUPR1+/ + HFD mice 15 weeks. Both LCAD and MCAD fatty acid metabolisms mRNA were also downregulated, as consequence of PPAR-alfa deficit. Similarly betaoxidation mRNA ACOX1 and CPT1-alfa, as well as MTC4 and PGK1 were downregulated in NUPR1-/- compared to NUPR1+/ + HFD mice 15 weeks. Conclusion: The results of this work confirm that NUPR1 act downstream of the PERK branch playing a crucial role of NUPR1 in the activation of UPR response in physio-pathological ER stress condition and suggest a potential contribution of NUPR1-mediated ER stress response to the development of liver steatosis

Nintedanib in non-small cell lung cancer: from preclinical to approval

Angiogenesis is a driving force of a tumor’s development. Targeting this process is an attractive option, as this is a feature shared by most of the solid tumors. A lot of antiangiogenic drugs have been developed following this path, including bevacizumab, sorafenib, sunitinib, vandetanib, ramucirumab, motesanib and many others. The latest drug of this class to be approved for patients with non-small cell lung cancer (NSCLC) was nintedanib, a triple angiokinase inhibitor. This molecule targets vascular endothelial growth factor (VEGF), platelet derived growth factor (PDGF) and fibroblast growth factor (FGF) pathways, avoiding the tumor’s switch to normal escape mechanisms. The pharmacokinetic, pharmacodynamic and toxicity profiles of nintedanib have been tested in several studies. These trials revealed it to be very interesting, as this agent did not lead to the classical adverse events of other tyrosine kinase inhibitors. A phase III clinical trial that recently concluded provided us with relevant information in patients with NSCLC of adenocarcinoma histology. Here we present a short overview of the tumor angiogenesis pathways and antiangiogenic drugs. In particular, we will focus on nintedanib, from the preclinical studies to the latest phase III clinical trial that allowed this new agent to be approved by the European Medicines Agency as a second-line treatment option in association with docetaxel for NSCLC patients with adenocarcinoma histology

NUPR1 interacts with eIF2α and is required for resolution of the ER stress response in pancreatic tissue

Nuclear protein 1 (NUPR1) is a stress response protein overexpressed upon cell injury in virtually all organs including the exocrine pancreas. Despite NUPR1\u27s well-established role in the response to cell stress, the molecular and structural machineries triggered by NUPR1 activation remain largely debated. In this study, we uncover a new role for NUPR1, participating in the unfolded protein response (UPR) and the integrated stress response. Biochemical results and ultrastructural morphological observations revealed alterations in the UPR of acinar cells of germline-deleted NUPR1 murine models, consistent with the inability to restore general protein synthesis after stress induction. Bioinformatic analysis of NUPR1-interacting partners showed significant enrichment in translation initiation factors, including eukaryotic initiation factor (eIF) 2α. Co-immunoprecipitation and proximity ligation assays confirmed the interaction between NUPR1 and eIF2α and its phosphorylated form (p-eIF2α). Furthermore, our data suggest loss of NUPR1 in cells results in maintained eIF2α phosphorylation and evaluation of nascent proteins by click chemistry revealed that NUPR1-depleted PANC-1 cells displayed a slower poststress protein synthesis recovery when compared to wild-type. Combined, these data propose a novel role for NUPR1 in the integrated stress response pathway, at least partially through promoting efficient PERK branch activity and resolution through a unique interaction with eIF2α

NUPR1 interacts with eIF2α and is required for resolution of the ER stress response in pancreatic tissue

International audienceNuclear protein 1 (NUPR1) is a stress response protein overexpressed upon cell injury in virtually all organs including the exocrine pancreas. Despite NUPR1’s well-established role in the response to cell stress, the molecular and structural machineries triggered by NUPR1 activation remain largely debated. In this study, we uncover a new role for NUPR1, participating in the unfolded protein response (UPR) and the integrated stress response. Biochemical results and ultrastructural morphological observations revealed alterations in the UPR of acinar cells of germline-deleted NUPR1 murine models, consistent with the inability to restore general protein synthesis after stress induction. Bioinformatic analysis of NUPR1-interacting partners showed significant enrichment in translation initiation factors, including eukaryotic initiation factor (eIF) 2α. Co-immunoprecipitation and proximity ligation assays confirmed the interaction between NUPR1 and eIF2α and its phosphorylated form (p-eIF2α). Furthermore, our data suggest loss of NUPR1 in cells results in maintained eIF2α phosphorylation and evaluation of nascent proteins by click chemistry revealed that NUPR1-depleted PANC-1 cells displayed a slower poststress protein synthesis recovery when compared to wild-type. Combined, these data propose a novel role for NUPR1 in the integrated stress response pathway, at least partially through promoting efficient PERK branch activity and resolution through a unique interaction with eIF2α

Prognostic and predictive biomarkers for targeted therapy in NSCLC: For whom the bell tolls?

Introduction: The discovery of molecular biomarkers and the advent of targeted therapies have led to a radical change in the treatment of several tumors, including NSCLC. In the last few years, the number of molecular biomarkers has rapidly increased, and a growing interest has been recently focused on their potential prognostic and predictive value in clinical settings. Areas covered: This review describes all the molecular biomarkers with prognostic and predictive value in NSCLC, including both clinically approved biomarkers, and emerging biomarkers under investigation in clinical trials. Liquid biopsy and applications of circulating biomarkers are also described. Expert opinion: The oncological research is currently focusing on the discovery and validation of molecular biomarkers in order to promote even more personalized treatment strategies. This paradigm of care will expand quickly thanks to the advent of new genotyping technologies, such as nextgeneration sequencing, making it possible to create a molecular-genomic profile of every patient’s tumor. Liquid biopsy and the use of circulatingbiomarkers represent the new challenge of oncological research, with very promising implications in the management of patients

PD-L1 expression as predictive biomarker in patients with NSCLC : a pooled analysis

Background: Clinical trials of immune checkpoints modulators, including both programmed cell death-1 (PD-1) and programmed cell death-ligand 1 (PD-L1) inhibitors, have recently shown promising activity and tolerable toxicity in pre-treated NSCLC patients. However the predictive role of PD-L1 expression is still controversial. This pooled analysis aims to clarify the association of clinical objective responses to anti PD-1/PD-L1 monoclonal antibodies (MoAbs) and tumor PD-L1 expression in pre-treated NSCLC patients. Methods: Data from published studies, that evaluated efficacy and safety of PD-1/PD-L1 inhibitors in pre-treated NSCLC patients, stratified by tumor PD-L1 expression status (immunohistochemistry, cut-off point 1%), were collected by searching in PubMed, Cochrane Library, American Society of Clinical Oncology, European Society of Medical Oncology and World Conference of Lung Cancer, meeting proceedings. Pooled Odds ratio (OR) and 95% confidence intervals (95% CIs) were calculated for the Overall Response Rate (ORR) (as evaluated by Response Evaluation Criteria in Solid Tumors, version 1.1), according to PD-L1 expression status. Results: A total of seven studies, with 914 patients, were eligible. Pooled analysis showed that patients with PD-L1 positive tumors (PD-L1 tumor cell staining 651%), had a significantly higher ORR, compared to patients with PD-L1 negative tumors (OR: 2.44; 95% CIs: 1.61-3.68). Conclusions: PD-L1 tumor over-expression seems to be associated with higher clinical activity of anti PD-1/PD-L1 MoAbs, in pre-treated NSCLC patients, suggesting a potential role of PD-L1 expression, IHC cut-off point 1%, as predictive biomarker for the selection of patients to treat with immune-checkpoint inhibitors