• cetuximab
• colorectal cancer
• comprehensive genomic profiling
• liquid biopsy

• Humans
• Colorectal Neoplasms/drug therapy
• Colorectal Neoplasms/genetics
• Colorectal Neoplasms/pathology
• Cetuximab/therapeutic use
• Cetuximab/pharmacology
• Cetuximab/administration & dosage
• Antineoplastic Combined Chemotherapy Protocols/therapeutic use
• Antineoplastic Combined Chemotherapy Protocols/pharmacology
• Leucovorin/therapeutic use
• Leucovorin/pharmacology
• Camptothecin/analogs & derivatives
• Camptothecin/therapeutic use
• Camptothecin/pharmacology
• Female
• Male
• Fluorouracil/therapeutic use
• Fluorouracil/pharmacology
• Liquid Biopsy/methods
• Middle Aged
• Aged
• Mutation
• Adult
• Treatment Outcome
• Proto-Oncogene Proteins B-raf/genetics
• Neoplasm Metastasis

• anti-epidermal growth factor receptor (EGFR) drugs
• circulating tumor DNA (ctDNA)
• colorectal cancer (CRC)
• comprehensive genomic profiling (CGP)
• liquid biopsy

• Humans
• Colorectal Neoplasms/genetics
• Colorectal Neoplasms/drug therapy
• Colorectal Neoplasms/pathology
• Proto-Oncogene Proteins B-raf/genetics
• Liquid Biopsy/methods
• Circulating Tumor DNA/genetics
• Circulating Tumor DNA/blood
• Female
• Male
• Mutation
• Cetuximab/administration & dosage
• Cetuximab/therapeutic use
• Aged
• Middle Aged
• Biomarkers, Tumor/genetics
• Proto-Oncogene Proteins p21(ras)/genetics
• GTP Phosphohydrolases/genetics
• Genetic Heterogeneity
• Prospective Studies
• Genomics/methods
• Neoplasm Metastasis
• Adult
• Membrane Proteins/genetics
• Gene Expression Profiling

• BRAF K601E mutation
• Binimetinib
• Case report
• Cetuximab
• Encorafenib
• Metastatic colorectal cancer

• Humans
• Colorectal Neoplasms/drug therapy
• Colorectal Neoplasms/pathology
• Colorectal Neoplasms/metabolism
• ErbB Receptors/metabolism
• ErbB Receptors/antagonists & inhibitors
• Signal Transduction
• Molecular Targeted Therapy/methods
• Antineoplastic Agents/therapeutic use
• Neoplasm Metastasis
• Drug Resistance, Neoplasm

• BRAF(V600E)
• Colorectal cancer
• Metastatic pattern
• Prognostic marker

Colorectal cancer (CRC) is the most common digestive malignancy across the world. Its first-line treatments applied in the routine clinical setting include surgery, chemotherapy, radiotherapy, targeted therapy, and immunotherapy. However, resistance to therapy has been identified as the major clinical challenge that fails the treatment method, leading to recurrence and distant metastasis. An increasing number of studies have been attempting to explore the underlying mechanisms of the resistance of CRC cells to different therapies, which can be summarized into two aspects: (1) The intrinsic characters and adapted alterations of CRC cells before and during treatment that regulate the drug metabolism, drug transport, drug target, and the activation of signaling pathways; and (2) the suppressive features of the tumor microenvironment (TME). To combat the issue of therapeutic resistance, effective strategies are warranted with a focus on the restoration of CRC cells’ sensitivity to specific treatments as well as reprogramming impressive TME into stimulatory conditions. To date, nanotechnology seems promising with scope for improvement of drug mobility, treatment efficacy, and reduction of systemic toxicity. The instinctive advantages offered by nanomaterials enable the diversity of loading cargoes to increase drug concentration and targeting specificity, as well as offer a platform for trying the combination of different treatments to eventually prevent tumor recurrence, metastasis, and reversion of therapy resistance. The present review intends to summarize the known mechanisms of CRC resistance to chemotherapy, radiotherapy, immunotherapy, and targeted therapy, as well as the process of metastasis. We have also emphasized the recent application of nanomaterials in combating therapeutic resistance and preventing metastasis either by combining with other treatment approaches or alone. In summary, nanomedicine is an emerging technology with potential for CRC treatment; hence, efforts should be devoted to targeting cancer cells for the restoration of therapeutic sensitivity as well as reprogramming the TME. It is believed that the combined strategy will be beneficial to achieve synergistic outcomes contributing to control and management of CRC in the future.

• Colorectal cancer
• Therapeutic resistance
• Nanotechnology
• Drug delivery system
• Combined treatment

• Humans
• Drug Resistance, Neoplasm
• Nanotechnology
• Drug Delivery Systems
• Immunotherapy
• Colorectal Neoplasms/drug therapy
• Tumor Microenvironment

• EGFR
• biomarker
• cetuximab
• colorectal cancer
• liquid biopsy

• Metastatic colorectal cancer
• clonal evolution
• epidermal growth factor receptor
• liquid biopsy
• maintenance
• molecular oncology
• systemic treatment

• immunotherapy
• metastatic colorectal cancer
• molecular target therapy
• precision medicine
• tumor molecular profiling

• Biomarkers, Tumor/genetics
• Biomarkers, Tumor/metabolism
• Colonic Neoplasms
• Colorectal Neoplasms/genetics
• Colorectal Neoplasms/therapy
• Humans
• Precision Medicine
• Prognosis
• Rectal Neoplasms
• Tumor Microenvironment

For patients with metastatic RAS/RAF wild-type refractory colorectal cancer, the question of anti-EGFR therapy rechallenge often comes up after initial use. However, not all patients derive benefit. It is now well known that these tumors acquire mechanisms of resistance in the mitogen-activated protein kinase (MAPK) pathway, which can be detected on circulating tumor DNA (ctDNA)-based testing. We present a series of patients who had serial testing post-EGFR blockade showing its feasibility and value. This would have implications for EGFR rechallenge. We reviewed records for patients who were initially noted to be RAS/RAF wild-type on tissue, who received prior anti-EGFR therapy and then subsequently had at least one circulating tumor DNA-based testing. These patients also had tissue-based genomic testing obtained earlier as part of their standard of care, alongside serial ctDNA-based testing that was done later when subsequent lines of therapy were being decided. The median duration of initial prior anti-EGFR therapy was around 10 months. Known acquired mechanisms of resistance were noted in 100% of the cases. These included KRAS, NRAS, extracellular domain mutations in EGFR, and BRAF mutations. Interestingly, the levels of the sub-clones expressed in variant allele fraction percentage varied and decreased over time in relation to timing of the prior EGFR exposure. Additionally, these were noted to be polyclonal, and the number of clones also varied including some disappearing over time during non-EGFR-based therapy (EGFR holiday). Patients’ post-EGFR blockade may have multiple mechanisms of acquired resistance that can be easily detected on non-invasive liquid biopsies. These patients do not benefit from EGFR rechallenge based on the results of the recently reported CRICKET (NCT02296203) and CAVE (NCT04561336) clinical trials. Furthermore, excluding these patients from EGFR rechallenge is already being adopted in prospectively done clinical trials, e.g., the CHRONOS study (NCT03227926). Rechecking the liquid biopsy plasma RAS/RAF status is one thing that may be incorporated into practice with EGFR rechallenge only a consideration if acquired mechanisms of resistance are absent.

• chemotherapeutic agents
• colorectal cancer
• drug resistance
• immunotherapy
• molecularly targeted therapy
• reversal strategies

• case report
• clinical–pathological features
• colorectal cancer
• concurrent RAS/BRAF variants
• mutation frequency

• BRAF
• Colorectal cancer
• Immunotherapy
• Non-V600E mutation
• Secondary resistance
• Targeted therapy
• Treatment algorithm
• V600E mutation

• anti-EGFR therapy
• cell-free DNA
• liquid biopsy
• metastatic colorectal cancer

• CUP B61G18000470007 and SURF 17061BP0000-00010 Campania Region

Colorectal cancer (CRC) represents one of the most frequent malignancies in terms of incidence and mortality, thus representing the third leading cause of cancer death worldwide. In the last decade, few drugs have enriched the treatment landscape of metastatic CRC and have significantly affected prognosis. Unlike other neoplasms, metastatic CRC patients who have exhausted treatment options often still maintain a good performance status. There are many challenges to increasing potential treatment options, notably a better understanding of disease biology and the mechanisms of resistance underlying cancer treatment failure. The development of new drugs for metastatic CRC certainly represents one of the most important challenges in medical oncology. This article discusses the main limitations in the development of new drugs and potential future scenarios. In particular, we addressed three questions: (1) The main limitations of targeted therapy in the treatment of metastatic CRC (mCRC); (2) New target armamentarium that could escape primary and secondary resistance and lead to more personalized mCRC therapy; and (3) Future directions.

• Colon cancer
• Colon rectal cancer
• New drugs
• Drug resistance
• Metastatic colorectal cancer

Cetuximab and panitumumab are monoclonal antibodies (mAbs) against epidermal growth factor receptor (EGFR) that are effective agents for metastatic colorectal cancer (mCRC). Cetuximab can prolong survival by 8.2 months in RAS wild-type (WT) mCRC patients. Unfortunately, resistance to targeted therapy impairs clinical use and efficiency. The mechanisms of resistance refer to intrinsic and extrinsic alterations of tumours. Multiple therapeutic strategies have been investigated extensively to overcome resistance to anti-EGFR mAbs. The intrinsic mechanisms include EGFR ligand overexpression, EGFR alteration, RAS/RAF/PI3K gene mutations, ERBB2/MET/IGF-1R activation, metabolic remodelling, microsatellite instability and autophagy. For intrinsic mechanisms, therapies mainly cover the following: new EGFR-targeted inhibitors, a combination of multitargeted inhibitors, and metabolic regulators. In addition, new cytotoxic drugs and small molecule compounds increase the efficiency of cetuximab. Extrinsic alterations mainly disrupt the tumour microenvironment, specifically immune cells, cancer-associated fibroblasts (CAFs) and angiogenesis. The directions include the modification or activation of immune cells and suppression of CAFs and anti-VEGFR agents. In this review, we focus on the mechanisms of resistance to anti-EGFR monoclonal antibodies (anti-EGFR mAbs) and discuss diverse approaches to reverse resistance to this therapy in hopes of identifying more mCRC treatment possibilities.

• Anti-epidermal growth factor receptor targeted therapies
• Drug resistance
• Metastatic colorectal cancer
• Reversal strategies

• Cetuximab
• Circulating tumour DNA
• Liquid biopsy
• Metastatic colorectal cancer
• NeoRAS wild-type
• Panitumumab
• ctDNA

Assessment of genetic mutations is an essential element in the modern era of personalized cancer treatment. Our strategy is focused on ‘multiple network analysis’ in which we try to improve cancer diagnostics by using biological networks. Genetic alterations in some important hubs or in driver genes such as BRAF and TP53 play a critical role in regulating many important molecular processes. Most of the studies are focused on the analysis of the effects of single mutations, while tumors often carry mutations of multiple driver genes. The aim of this work is to define an innovative bioinformatics pipeline focused on the design and analysis of networks (such as biomedical and molecular networks), in order to: (1) improve the disease diagnosis; (2) identify the patients that could better respond to a given drug treatment; and (3) predict what are the primary and secondary effects of gene mutations involved in human diseases.

By using our pipeline based on a multiple network approach, it has been possible to demonstrate and validate what are the joint effects and changes of the molecular profile that occur in patients with metastatic colorectal carcinoma (mCRC) carrying mutations in multiple genes. In this way, we can identify the most suitable drugs for the therapy for the individual patient. This information is useful to improve precision medicine in cancer patients. As an application of our pipeline, the clinically significant case studies of a cohort of mCRC patients with the BRAF V600E-TP53 I195N missense combined mutation were considered.

The procedures used in this paper are part of the Cytoscape Core, available at (www.cytoscape.org). Data used here on mCRC patients have been published in [55].

A supplementary file containing a more detailed discussion of this case study and other cases is available at the journal site as Supplementary Data.

• biological-biomedical networks
• colorectal cancer
• personalized medicine
• pipeline workflow

• Cetuximab
• bevacizumab
• colorectal cancer
• overall survival
• postmenopausal women
• progression-free survival

• cancer-associated fibroblasts
• colorectal cancer
• immunotherapy
• p53
• signaling
• systemic therapy
• targeted therapy
• tumor microenvironment (TME)

The survival of patients with metastatic colorectal cancer (mCRC) has been improved over the years and now reaches 30–40 months. However, few therapeutic options are available after failure of first- and second-line treatments. In fact, prognosis of chemo-refractory mCRC remains poor. Therefore, new therapeutic strategies are needed. Emerging evidence suggest that retreatment with epidermal growth factor (EGFR) inhibitors after a treatment break, in patients that obtained a clinical benefit by previous anti-EGFR, could lead to prolonged survival. The rationale beyond this “rechallenge” strategy is that after a “treatment holiday” EGFR resistant cancer cells decay, restoring the sensibility to EGFR blockade. In this review we analyze the current knowledge of retreatment with EGFR inhibitors, examine the role of novel biomarkers that can guide the appropriate selection of patients. Finally, we discuss future perspectives and on-going clinical trials.

The prognosis of patients with metastatic colorectal cancer (mCRC) who progressed to the first and the second lines of treatment is poor. Thus, new therapeutic strategies are needed. During the last years, emerging evidence suggests that retreatment with anti-epidermal growth factor receptor (EGFR) monoclonal antibodies (MAbs) in the third line of mCRC patients, that have previously obtained clinical benefit by first-line therapy with anti-EGFR MAbs plus chemotherapy, could lead to prolonged survival. The rationale beyond this “rechallenge” strategy is that, after disease progression to first line EGFR-based therapy, a treatment break from anti-EGFR drugs results in RAS mutant cancer cell decay, restoring the sensitivity of cancer cells to cetuximab and panitumumab. In fact, rechallenge treatment with anti-EGFR drugs has shown promising clinical activity, particularly in patients with plasma RAS and BRAF wild type circulating tumor DNA, as defined by liquid biopsy analysis at baseline treatment. The aim of this review is to analyze the current knowledge on rechallenge and to investigate the role of novel biomarkers that can guide the appropriate selection of patients that could benefit from this therapeutic strategy. Finally, we discuss on-going trials and future perspectives.

• anti-EGFR monoclonal antibodies
• metastatic colorectal cancer
• rechallenge

• BRAF V600E
• BRAF mutation
• BRAF non-V600E
• colorectal cancer
• microsatellite instability (MSI)

• anti-epidermal growth factor receptor monoclonal antibodies
• liquid biopsy
• metastatic colorectal cancer
• molecular selection
• predictive biomarkers
• rechallenge therapy

• Adult
• Aged
• Aged, 80 and over
• Biomarkers, Tumor/genetics
• Cetuximab/pharmacology
• Cetuximab/therapeutic use
• Colorectal Neoplasms/drug therapy
• Colorectal Neoplasms/genetics
• Colorectal Neoplasms/mortality
• DNA Mutational Analysis
• Drug Resistance, Neoplasm/genetics
• Female
• GTP Phosphohydrolases/genetics
• Gene Frequency
• Humans
• Male
• Membrane Proteins/genetics
• Middle Aged
• Mutation
• Progression-Free Survival
• Proto-Oncogene Proteins B-raf/genetics
• Proto-Oncogene Proteins p21(ras)/genetics

• P50 CA221707 NCI NIH HHS
• R01 CA184843 NCI NIH HHS
• R01 CA187238 NCI NIH HHS
• R01 CA218230 NCI NIH HHS
• R01 CA172670 NCI NIH HHS

• CAPOX
• Colorectal cancer
• FOLFOX
• Rechallenge
• Reintroduction
• XELOX

While the BRAF V600E mutation occurs in 5%–15% of metastatic colorectal cancer (mCRC), BRAF non-V600E mutations were recently reported to range from 1.6% to 5.1%. We have previously reported that BRAF non-V600E mutations could have a negative impact on efficacy outcomes as well as BRAF V600E mutation for antiepidermal growth factor receptor (EGFR) antibody treatment for pretreated patients with mCRC. Recently, simultaneous inhibitions of mitogen-activated protein kinase kinase (MEK), BRAF and EGFR exhibited relevant antitumour activities in patients with BRAF V600E mutant and also in BRAF non-V600E mutant but only in the preclinical model.

The BIG BANG (study is a multicentre, phase II study to assess the efficacy, safety and proof of concept of the combinations of binimetinib+encorafenib+cetuximab in patients with BRAF non-V600E mutated mCRC, identified by either tumour tissue (tumour tissue group) or blood samples (liquid biopsy group). Key eligibility criteria include Eastern Cooperative Oncology Group Performance Status of ≤1, mCRC with BRAF non-V600E mutant and RAS wild type, refractory or intolerant to at least one fluoropyrimidine-based regimen and no prior history of regorafenib, and no prior history of anti-EGFR antibody treatment (primary analysis cohort and liquid biopsy cohort) or refractory to prior anti-EGFR antibody treatment in patients with class 3 BRAF mutations (anti-EGFR antibody refractory class three cohort). Enrolled patients receive binimetinib (45 mg, two times per day), encorafenib (300 mg, once a day) and cetuximab (initially 400 mg/m² and subsequently 250 mg/m², once per week). The primary endpoint is the confirmed objective response rate in the primary analysis cohort.

UMIN000031857 and 000031860.

• BRAF non-V600E
• binimetinib
• cetuximab
• encorafenib
• metastatic colorectal cancer

The treatment of metastatic colorectal cancer (mCRC) has improved since the introduction of the epithelial growth factor receptor (EGFR) inhibitors as cetuximab and panitumumab. However, only patients with peculiar genomic profiles benefit from these targeting therapies. In fact, the molecular integrity of RAS genes is a predominant factor conditioning both primary and acquired resistance in non-responders although additional molecular derangements induced by selective anti-EGFR pressure may concur to the failure of those disease treatment, liquid biopsy (LB) appears as a surrogate of tissue biopsy, provides the genomic information to reveal tumor resistance to anti-EGFR agents, the detection of minimal residual disease before adjuvant therapies, and the discovery of tumor molecular status suitable for rechallenging treatments with EGFR antagonists. LB investigates circulating tumor cells (CTCs), cell-free tumor DNA (ctDNA), and tumor-derived exosomes. In mCRC, ctDNA analysis has been demonstrated as a useful method in the mutational tracking of defined genes as well as on tumor burden and detection of molecular alterations driving the resistance to anti-EGFR targeting treatments. However, despite their efficiency in molecular diagnosis and prognostic evaluation of mCRC, the affordability of these procedures is prevalently restricted to research centers, and the lack of consensus validation prevents their translation to clinical practice. Here, we revisit the major mechanisms responsible for resistance to EGFR blockade and review the different methods of LB potentially useful for treatment options in mCRC.

• EGRF
• cetuximab
• colorectal cancer
• liquid biopsy
• panitumumab
• resistance

• AXL
• Colorectal cancer
• EGFR resistance
• RAS WT

• Animals
• Biomarkers
• Cell Line, Tumor
• Colorectal Neoplasms/chemistry
• Colorectal Neoplasms/drug therapy
• Colorectal Neoplasms/mortality
• Colorectal Neoplasms/pathology
• Drug Resistance, Neoplasm
• ErbB Receptors/antagonists & inhibitors
• Genes, ras
• Humans
• Mice
• Neoplasm Metastasis
• Proto-Oncogene Proteins/analysis
• Receptor Protein-Tyrosine Kinases/analysis
• Xenograft Model Antitumor Assays
• Axl Receptor Tyrosine Kinase

• cancer genetics
• group 1: major specialty, molecular genetics
• group 3: other specific research areas
• group 3: other specific research areas, tumor markers

• High-Throughput Nucleotide Sequencing/methods
• Humans
• Neoplasms/genetics
• Singapore

• HIPEC
• carcinomatosis
• mutations
• peritoneal metastasis
• survival

• Adenocarcinoma, Mucinous/genetics
• Adenocarcinoma, Mucinous/pathology
• Adenocarcinoma, Mucinous/surgery
• Adult
• Aged
• Aged, 80 and over
• Biomarkers, Tumor/genetics
• Cytoreduction Surgical Procedures/mortality
• DNA Mutational Analysis/methods
• Female
• Follow-Up Studies
• Gastrointestinal Neoplasms/genetics
• Gastrointestinal Neoplasms/pathology
• Gastrointestinal Neoplasms/surgery
• High-Throughput Nucleotide Sequencing
• Humans
• Male
• Middle Aged
• Mutation
• Peritoneal Neoplasms/genetics
• Peritoneal Neoplasms/pathology
• Peritoneal Neoplasms/surgery
• Prognosis
• Retrospective Studies
• Survival Rate
• Young Adult

• Biomarkers
• Colorectal cancer
• Epidermal growth factor receptor
• Mechanism of resistance
• Molecular alterations
• Monoclonal antibodies
• Mutant allele fraction

• BTK inhibitors
• TP53
• colon cancer
• drug-resistance
• p65BTK

• Biomarkers, Tumor/genetics
• Drug Resistance, Neoplasm/genetics
• ErbB Receptors/antagonists & inhibitors
• ErbB Receptors/genetics
• Humans
• Molecular Targeted Therapy
• Mutation
• Neoplasms/drug therapy
• Neoplasms/genetics
• Neoplasms/pathology
• Protein Kinase Inhibitors/pharmacology

• P50 CA221707 NCI NIH HHS
• R01 CA187238 NCI NIH HHS

• MAF
• RAS analysis
• circulating tumor DNA
• metastatic colorectal cancer
• prognostic biomarker

• anti-EGFR monoclonal antibodies
• colorectal cancer
• genomic profiling
• resistance

• IG17135 Associazione Italiana per la Ricerca sul Cancro
• M4/10 Ministero della Salute (Ricerca corrente)