Despite the improvement in clinical outcomes derived by the introduction of epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (EGFR-TKIs) in the treatment of patients with advanced ...non-small cell lung cancer (NSCLC) whose tumours harbour EGFR-activating mutations, prognosis remains unfavourable because of the occurrence of either intrinsic or acquired resistance. We reviewed the published literature and abstracts of oral and poster presentations from international conferences addressing EGFR-TKIs resistance mechanisms discovered in preclinical models and in patients with NSCLC. The molecular heterogeneity of lung cancer has several implications in terms of possible mechanisms of either intrinsic or acquired resistance to EGFR-targeted inhibitors. Several mechanisms of resistance have been described to EGFR-TKIs, such as the occurrence of secondary mutation (T790M, C797S), the activation of alternative signalling (Met, HGF, AXL, Hh, IGF-1R), the aberrance of the downstream pathways (AKT mutations, loss of PTEN), the impairment of the EGFR-TKIs-mediated apoptosis pathway (BCL2-like 11/BIM deletion polymorphism) and histological transformation. Although some of the mechanisms of resistance have been identified, much additional information is needed to understand and overcome resistance to EGFR-TKI agents. The majority of resistance mechanisms described are the result of a selection of pre-existing clones; thus, studies on the mechanisms by which subclonal alterations have an impact on tumour biology and influence cancer progression are extremely important in order to define the best treatment strategy.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The prognosis for patients who are diagnosed with advanced stage hepatocellular carcinoma(HCC)is poor because there are few treatment options.Recent research has focused on the identification of ...novel molecular entities that can be targeted to inhibit oncogenic signals that are involved in the carcinogenesis,proliferation and progression of HCC.Among all of the pathways that are involved in the development of HCC,Hedgehog(HH)signalling has demonstrated a substantial role in hepatocarcinogenesis and HCC progression.HH plays a physiological role in embryogenesis,through the induction of the differentiation of hepatocytes from endodermal progenitors.The re-activation of the HH pathway in chronic damaged liver is a mechanism of fibrotic degeneration and is implicated in various stages of HCC development.HH activation sustains the subpopulation of immature liver epithelial cells that are involved in the pathogenesis of cirrhosis and HCC,and HH itself is a mediator of the alcohol-derived malignant transformation of liver cells.High levels of expression of HH protein markers in liver tumour tissues are correlated with aggressive histological and biological features and a poor clinical outcome.In vitro and in vivo inhibition models of the HH pathway confirm that HH is essential in maintaining tumour growth,metastasis and a mesenchymal phenotype.
An overactivation of hepatocyte growth factor (HGF)/mesenchymal-epithelial transition factor (MET) axis promotes tumorigenesis and tumor progression in various cancer types. Research data recently ...evidenced that HGF/MET signaling is also involved also in the immune response, mainly modulating dendritic cells functions. In general, the pathway seems to play an immunosuppressive role, thus hypothesizing that it could constitute a mechanism of primary and acquired resistance to cancer immunotherapy. Recently, some approaches are being developed, including drug design and cell therapy to combine MET and programmed cell death receptor-1 (PD-1)/programmed cell death receptor-ligand 1 (PD-L1) inhibition. This approach could represent a new weapon in cancer therapy in the future.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Gastrointestinal cancer represents one of the most diagnosed types of cancer. Cancer is a genetic and multifactorial disease, influenced by the host and environmental factors. It has been stated that ...20% of cancer is caused by microorganisms such as
, hepatitis B and C virus, and human papillomavirus. In addition to these well-known microorganisms associated with cancer, it has been shown differences in the composition of the microbiota between healthy individuals and cancer patients. Some studies have suggested the existence of the selected microorganisms and their metabolites that can promote or inhibit tumorigenesis
some mechanisms. Recent findings have shown that gut microbiome and their metabolites can act as cancer promotors or inhibitors. It has been shown that gastrointestinal cancer can be caused by a dysregulation of the expression of non-coding RNA (ncRNA) through the gut microbiome. This review will summarize the latest reports regarding the relationship among gut microbiome, ncRNAs, and gastrointestinal cancer. The potential applications of diagnosing and cancer treatments will be discussed.
Anaplastic lymphoma kinase (ALK) gene activation is involved in the carcinogenesis process of several human cancers such as anaplastic large cell lymphoma, lung cancer, inflammatory myofibroblastic ...tumors and neuroblastoma, as a consequence of fusion with other oncogenes (NPM, EML4, TIM, etc) or gene amplification, mutation or protein overexpression. ALK is a transmembrane tyrosine kinase receptor that, upon ligand binding to its extracellular domain, undergoes dimerization and subsequent autophosphorylation of the intracellular kinase domain. When activated in cancer it represents a target for specific inhibitors, such as crizotinib, ceritinib, alectinib etc. which use has demonstrated significant effectiveness in ALK-positive patients, in particular ALK-positive non- small cell lung cancer. Several mechanisms of resistance to these inhibitors have been described and new strategies are underway to overcome the limitations of current ALK inhibitors.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Morgillo et al present a comprehensive review from tumor microenvironment to gut microbiota of carcinogenesis as a result of multiple inflammatory and oxidative hits. They analyze, from a particular ...perspective, the different ways to induce inflammation and oxidative stress in order to explain the mechanisms underlying the development of several cancers. Moreover, because of the strong scientific evidence in literature, Morgillo et al focused their attention to the analysis of the role that gut microbiota plays in gastrointestinal cancer development/promotion.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
EGFR regulates cancer-cell proliferation, apoptosis and tumor-induced neoangiogenesis, and has been validated as a relevant therapeutic target in several human cancers, including metastatic ...colorectal cancer (mCRC). The anti-EGFR monoclonal antibodies cetuximab and panitumumab are available for the treatment of patients with mCRC. Although EGFR is expressed in approximately 85% of patients with mCRC, the clinical efficacy of treatment with anti-EGFR antibodies is limited to a subset of patients. A series of potential biomarkers that could be useful in predicting response to EGFR inhibitors has been investigated. In patients with mCRC, activating mutations within KRAS can predict resistance to anti-EGFR monoclonal antibodies. Activating mutations in KRAS, which could result in EGFR-independent intracellular signal transduction activation, are found in approximately 35-40% of patients with mCRC. These mutations are almost exclusively detected in codons 12 and 13 of exon 2. KRAS mutations have been significantly associated with lack of response to cetuximab or panitumumab therapy in patients with mCRC, which suggests that EGFR-independent, constitutive activation of the RAS signaling pathway could impair response to anti-EGFR drugs. We summarize the experimental and clinical evidence supporting the use of KRAS testing for the optimal selection of patients with mCRC to be treated with anti-EGFR monoclonal antibodies.
In the last two decades, great efforts have been made in the treatment of metastatic colorectal cancer (mCRC) due to the approval of new target agents for cytotoxic drugs. Unfortunately, a large ...percentage of patients present with metastasis at the time of diagnosis or relapse after a few months. The complex molecular heterogeneity of this disease is not completely understood; to date, there is a lack of predictive biomarkers that can be used to select subsets of patients who may respond to target drugs. Only the
-mutation status is used to predict resistance to anti-epidermal growth factor receptor agents in patients with mCRC. In this review, we describe approved targeted therapies for the management of metastatic mCRC and discuss new candidate targets on the horizon.
Head and neck cancers (HNC) represent the seventh most frequent cancer worldwide, with squamous cell carcinomas as the most frequent histologic subtype. Standard treatment for early stage diseases is ...represented by single modality surgery or radiotherapy, whereas in the locally advanced and recurrent or metastatic settings a more aggressive multi-modal approach is needed with locoregional intervention and/or systemic therapies. Epidermal Growth Factor Receptor (EGFR) plays an important role in HNC biology and has been studied extensively in preclinical and clinical settings. In this scenario, anti-EGFR targeted agent cetuximab, introduced in clinical practice a decade ago, represents the only approved targeted therapy to date, while the development of immune-checkpoint inhibitors has recently changed the available treatment options. In this review, we focus on the current role of anti-EGFR therapies in HNCs, underlying available clinical data and mechanisms of resistance, and highlight future perspectives regarding their role in the era of immunotherapy.
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