ANCHOR CRC: Results From a Single-Arm, Phase II Study of Encorafenib Plus Binimetinib and Cetuximab in Previously Untreated BRAFV600E-Mutant Metastatic Colorectal Cancer

Durable response to third-line combination therapy in a metastatic colorectal cancer patient with BRAF V600E mutation: A case report

In metastatic colorectal cancer (mCRC), the BRAFV600E mutation subtype is one of the subtypes with the worst prognosis. The long-term abnormal activation of multiple signaling pathways caused by the BRAF V600E mutation is closely related to the formation of BRAF inhibitor resistance and drug-resistant tumor cell subpopulations. These factors significantly impact the survival and prognosis of CRC patients. Therefore, treating mCRC patients with the BRAFV600E mutation, particularly in later stages, is challenging. We reported a case of an mCRC patient with the BRAF V600E mutation in the primary and metastatic tumors. After the failure of second-line treatment, this patient received a combination therapy including immunotherapy (tislelizumab), radiotherapy, and targeted therapy (fruquintinib). Through comprehensive imaging evaluations and continuous monitoring of tumor markers, we were astonished to observe that the patient has achieved and maintained a complete response (CR) for over 12 months. This case supports the efficacy of combination therapy in mCRC patients with the BRAF V600E mutation.

Encorafenib, Cetuximab, and mFOLFOX6 in BRAF-Mutated Colorectal Cancer

BACKGROUND

First-line treatment with encorafenib plus cetuximab (EC) with or without chemotherapy (oxaliplatin, leucovorin, and fluorouracil [mFOLFOX6]) for BRAF V600E-mutated metastatic colorectal cancer, an aggressive subtype with a poor prognosis, was compared with standard care (chemotherapy with or without bevacizumab) in an open-label, phase 3 trial, which showed significance regarding one of the two primary end points, objective response according to blinded independent central review (odds ratio for EC+mFOLFOX6 vs. standard care, 2.44; one-sided P<0.001). This result led to accelerated Food and Drug Administration approval of this investigational combination therapy for BRAF V600E-mutated metastatic colorectal cancer, including as first-line therapy. Data on progression-free survival (the second primary end point) and an updated interim analysis of overall survival are now available.

METHODS

We randomly assigned patients with untreated BRAF V600E-mutated metastatic colorectal cancer to receive EC, EC+mFOLFOX6, or standard care. The two primary end points were objective response (reported previously) and progression-free survival according to blinded independent central review in the EC+mFOLFOX6 group and the standard-care group. The key secondary end point was overall survival.

RESULTS

Significantly longer progression-free survival was seen with EC+mFOLFOX6 than with standard care (median, 12.8 vs. 7.1 months; hazard ratio for progression or death, 0.53; 95% confidence interval [CI], 0.41 to 0.68; P<0.001). In an interim analysis, overall survival was significantly longer with EC+mFOLFOX6 than with standard care (median, 30.3 vs. 15.1 months; hazard ratio for death, 0.49; 95% CI, 0.38 to 0.63; P<0.001). The incidence of serious adverse events during treatment was 46.1% with EC+mFOLFOX6 and 38.9% with standard care. Safety profiles were consistent with those known for each agent.

CONCLUSIONS

This trial showed significantly longer progression-free survival and overall survival with first-line treatment with EC+mFOLFOX6 than with standard care among patients with BRAF V600E-mutated metastatic colorectal cancer. (Funded by Pfizer and others; BREAKWATER ClinicalTrials.gov number, NCT04607421.).

Oral squamous cell carcinoma: Insights into cellular heterogeneity, drug resistance, and evolutionary trajectories

Oral squamous cell carcinoma (OSCC) can lead to metastasis and high mortality rates known for its aggressive and invasive properties. Currently, primary treatment options of surgical resection, chemotherapy and radiotherapy have many therapeutic limitations for OSCC patients due to its dynamic evolutionary pathways and the development of resistance to conventional therapies. Moreover, previous studies fail to emphasize the roles of cellular heterogeneity, drug resistance, and evolutionary trajectories in OSCC. This review explores the intricate tumor microenvironment landscape of OSCC, focusing on the cellular heterogeneity, drug resistance, and evolutionary trajectories as well as genetic, epigenetic, and environmental risk factors contributing to the OSCC progression. Tumor heterogeneity arises from environmental exposures (e.g., tobacco, HPV infection, dietary carcinogens) that drive clonal evolution, creating subpopulations of cells with distinct mutational profiles and therapeutic vulnerabilities. Recent advances in in the precision medicine and combination therapy of OSCC paves the way for innovative therapeutic strategies, such as targeting molecular subclones through real-time monitoring and leveraging computational models to predict treatment response. By recognizing tumor heterogeneity as both a driver of therapeutic resistance and a therapeutic target, precision medicine frameworks can integrate environmental risk factor data, molecular profiling, and early detection tools to optimize outcomes. This review underscores the necessity for a multidisciplinary approach to understand and combat the complexity of OSCC, proposing directions for future research to enhance diagnosis and treatment efficacy.

The interplay between driver mutation and oxidative stress in colorectal cancer: from pathogenesis to therapeutics

Colorectal cancer (CRC) is a multifaceted disease influenced by genetic mutations and environmental factors, especially oxidative stress. Driver mutations are pivotal in CRC initiation and progression and alter key signaling pathways involved in cell proliferation, apoptosis, and genomic stability. Concurrently, oxidative stress, characterized by an imbalance between reactive oxygen species (ROS) production and antioxidant defenses, plays a crucial role in CRC development by promoting DNA damage, lipid peroxidation, and redox signaling dysregulation. The molecular mechanisms linking driver mutations and oxidative stress pathways underscore their collective or antagonistic impact on CRC heterogeneity, therapeutic responses, and clinical outcomes. Insights into mutation-specific vulnerabilities and redox modulation offer promising avenues for targeted therapies and personalized medicine approaches in CRC treatment. Here, we discuss the intricate interplay between driver mutations and oxidative stress, highlight emerging trends, and propose future research directions to advance our understanding of CRC pathogenesis and optimize therapeutic interventions.

Recent advances and challenges in colorectal cancer: From molecular research to treatment

Colorectal cancer (CRC) ranks among the top causes of cancer-related fatalities globally. Recent progress in genomics, proteomics, and bioinformatics has greatly improved our comprehension of the molecular underpinnings of CRC, paving the way for targeted therapies and immunotherapies. Nonetheless, obstacles such as tumor heterogeneity and drug resistance persist, hindering advancements in treatment efficacy. In this context, the integration of artificial intelligence (AI) and organoid technology presents promising new avenues. AI can analyze genetic and clinical data to forecast disease risk, prognosis, and treatment responses, thereby expediting drug development and tailoring treatment plans. Organoids replicate the genetic traits and biological behaviors of tumors, acting as platforms for drug testing and the formulation of personalized treatment approaches. Despite notable strides in CRC research and treatment - from genetic insights to therapeutic innovations - numerous challenges endure, including the intricate tumor microenvironment, tumor heterogeneity, adverse effects of immunotherapies, issues related to AI data quality and privacy, and the need for standardization in organoid culture. Future initiatives should concentrate on clarifying the pathogenesis of CRC, refining AI algorithms and organoid models, and creating more effective therapeutic strategies to alleviate the global impact of CRC.

miR-196b strictly regulates and reliably predicts the response to cetuximab in colorectal cancer

BACKGROUND

Cetuximab resistance severely restricts its effectiveness in the treatment of patients with metastatic colorectal cancer (CRC). Previous studies have predominantly focused on the genetic level, with scant attention to the nongenetic aspects. This study aimed to identify the crucial microRNA (miRNA) that is responsible for cetuximab resistance.

METHODS

Key miRNAs were identified using small RNA sequencing analysis. miR-196b's role and mechanism in cetuximab resistance was explored by in vitro and in vivo experiments. Clinical blood samples were dynamically analyzed using droplet digital polymerase chain reaction (PCR) to assess the predictive value of miR-196b for efficacy.

RESULTS

We initially discovered that the extracellular signal-regulated kinase (ERK) signaling pathway was progressively activated during the acquisition of cetuximab resistance in CRC cells. Further study determined that miR-196b can inhibit the activity of ERK and protein kinase B (AKT) signaling pathways by downregulating both NRAS and BRAF, which can kill two birds with one stone, thus enhancing the sensitivity of colorectal cancer cells to cetuximab. The expression of miR-196b was found to be significantly downregulated in both cetuximab-resistant cells and the tumor tissues of patients exhibiting resistance. In the presence of cetuximab, overexpression of miR-196b further inhibited the proliferation and migration and promoted the apoptosis of CRC cells, while miR-196b silencing had the opposite effects. Importantly, analysis of clinical blood samples confirmed that miR-196b can serve as a predictive and dynamic biomarker for monitoring the outcomes of patients with CRC treated with cetuximab.

CONCLUSIONS

This study supports that activation of the ERK signaling pathway is a key factor in cetuximab resistance. In addition, miR-196b can modulate and predict the CRC response to cetuximab, holding broad potential applications.

Investigation of the cytotoxic effects and mechanisms of the SLC39A6-targeting ADC drug BRY812 in CRC

Colorectal cancer (CRC) is a leading cause of cancer-related deaths worldwide, necessitating the development of novel therapeutic strategies. We explore the expression characteristics of SLC39A6 in CRC by combining multiple cohorts and multi-omics. The therapeutic effect and potential mechanism of BRY812 on CRC were explored through in vitro experiments. Our research results show that the expression of SLC39A6 in CRC tissues is higher than that in normal tissues, and it is closely related to tumor pathways, making it a good therapeutic target. BRY812 has an inhibitory effect on the growth, migration and stemness of CRC cells, and may exert its killing effect by downregulating the AKT pathway. This study has identified SLC39A6 as a potential therapeutic target in CRC. BRY812 is expected to become a highly promising therapeutic drug, bringing new hope to patients with CRC.

Decoding colorectal cancer targeted therapy: a bibliometric journey of the last decade (2015-2024)

Colorectal cancer remains one of the most commonly diagnosed cancers globally, with a significant impact on public health. Targeted therapies have revolutionized the treatment landscape for colorectal cancer by offering increased specificity and reduced systemic toxicity compared to conventional chemotherapy. This study provides a comprehensive bibliometric analysis of global research on targeted therapy for colorectal cancer, focusing on publications from 2015 to 2024. A total of 3213 publications were retrieved from the Web of Science Core Collection and analyzed using bibliometric tools to construct knowledge maps and visualize research trends. The regression analysis shows a strong upward trend in publications from 2015 to 2024 (P < 0.001, R2 = 0.889). China leads in publication output, with the University of Texas MD Anderson Cancer Center contributing the highest number of studies. Tabernero and Kopetz are the core authors in the field. Research in this domain has primarily concentrated on the development and clinical assessment of drugs targeting the EGFR, RAS, VEGF, and BRAF signaling pathways, as well as investigating the pathogenesis, drug resistance, and metastatic mechanisms of colorectal cancer. Current advancements emphasize Artificial Intelligence-driven multi-omics integration, the creation of novel therapeutics targeting established molecular pathways, and the execution of global clinical trials to validate personalized treatment strategies.

Colon cancer biology and treatment in the era of precision oncology: A primer for Radiologists

In the era of precision oncology, systemic therapies for colon cancer are becoming increasingly biomarker-led, with implications for patients in the neoadjuvant, adjuvant and metastatic settings. As the landscape for colon cancer treatment evolves and becomes more complex, it is important that all members of the multidisciplinary team keep abreast of developments to ensure the most effective care is delivered to patients. As core members of the colorectal multidisciplinary team, Radiologists play a central role throughout the patient journey. This review serves as an educational summary of current and emerging treatment pathways in colon cancer, standards for biomarker testing, mechanisms of action for key drugs, important treatment-related complications, relevant tumour biology that underpins patterns of disease and treatment response, and the specific implications systemic therapies have for cancer imaging and Radiologists. We also highlight the increasing role for radiology in patient stratification and the importance of imaging biomarkers. It is crucial that Radiologists understand the current landscape of colon cancer treatment and emerging strategies on the horizon in clinical trials. Only through engagement across the wider multidisciplinary team will we deliver true personalised medicine for patients with colon cancer.

Real-world evaluation of treatment patterns and clinical outcomes in patients with BRAF-V600E metastatic colorectal cancer (mCRC) in Canada

BACKGROUND

BRAF V600E mutations are identified in 10 % of metastatic colorectal cancer (mCRC) cases. In this project, we evaluated the clinicopathologic features and natural history of patients with BRAF mutant (BRAF-mt) mCRC prior to era of BRAF targeted therapy.

METHODS

This is a retrospective project evaluating patients with diagnosed with mCRC with an identified BRAF V600E mutation between January 1, 2015 and December 31, 2021 seen at the Ottawa Hospital Cancer Centre prior to the approval of cetuximab and encorafenib in Canada. Demographic, clinical, and cancer characteristics were collected from the medical records. Outcomes of interest included overall survival (OS) and time to next therapy (TNT).

RESULTS

71 patients were included. The median age was 69 years, 37 (52 %) patients were females, and 19 (27 %) were mismatch repair deficient (dMMR). Median OS was 12.9 months with 21 (30 %) patients living greater than 2-years. Signet ring histology (HR=7.27, p < 0.001), peritoneal metastasis (HR=2.29, 0.003), distant lymphatic metastasis (HR=2.70, p < 0.001), brain metastasis (HR=2.86, p < 0.048) and metastatectomy (HR=0.17, p < 0.001) were associated with OS. Forty-six (65 %) patients received first-line systemic therapy, 14 (20 %) second-line and 2 (3 %) third-line. Median duration of therapy was 8.5 months for first-line, 5.5 months for second-line and 1.5 months for third-line.

CONCLUSION

Real world data demonstrates that patients with BRAF-V600E mCRC have poor clinical outcomes with traditional systemic therapies. Only a minority of patients received second- or third-line systemic treatments, highlighting the importance of ongoing research evaluating incorporation of targeted therapy in first-line treatment.

BRAFV600E mutant metastatic colorectal cancer: Current advances in personalized treatment and future perspectives

Detection of the BRAF V600E mutation has important genetic, prognostic, and therapeutic implications for patients with metastatic colorectal cancer (mCRC), identifying a subgroup of patients who derive modest benefit from standard treatments and have extremely poor prognosis. The evolution of molecular profiling and the implementation of next generation sequencing in the evaluation of a patient with BRAF-mutated mCRC has currently led to the discovery of actionable alterations. Targeting multiple pathways of resistance in BRAF-mutated mCRC may be the most efficacious route. Then, over a short period of time, the treatment landscape BRAF-mutated mCRC patients has shifted dramatically. Finally, novel treatment strategies are available. This review will discuss on currently approved treatments for BRAF V600E mutated mCRC and will try and portray the changing landscape in this setting in the era of targeted molecular therapy.

Encorafenib, cetuximab and chemotherapy in BRAF-mutant colorectal cancer: a randomized phase 3 trial

Encorafenib + cetuximab (EC) is approved for previously treated BRAF V600E-mutant metastatic colorectal cancer (mCRC) based on the BEACON phase 3 study. Historically, first-line treatment of BRAF V600E-mutant mCRC with chemotherapy regimens has had limited efficacy. The phase 3 BREAKWATER study investigated EC+mFOLFOX6 versus standard of care (SOC) in patients with previously untreated BRAF V600E mCRC. The dual primary endpoint of progression-free survival is event driven; data were not mature at data cutoff. BREAKWATER met the other dual primary endpoint of objective response rate, demonstrating significant and clinically relevant improvement in objective response rate (EC+mFOLFOX6: 60.9%; SOC: 40.0%; odds ratio, 2.443; 95% confidence interval (CI): 1.403-4.253; 99.8% CI: 1.019-5.855; one-sided P = 0.0008). Median duration of response was 13.9 versus 11.1 months. At this first interim analysis of overall survival, the hazard ratio was 0.47 (95% CI: 0.318-0.691; repeated CI: 0.166-1.322). Serious adverse event rates were 37.7% versus 34.6%. The safety profiles were consistent with those known for each agent. BREAKWATER demonstrated a significantly improved response rate that was durable for first-line EC+mFOLFOX6 versus SOC in patients with BRAF V600E mCRC. ClinicalTrials.gov identifier: NCT04607421 .

Clinical Implications of Cell-Free DNA in Managing BRAF V600E Mutation-Positive Colorectal Cancer

Background/Objectives:BRAFV600E-mutant colorectal cancer (CRC) is associated with poor prognosis, and despite the introduction of BEACON therapy, significant treatment challenges remain. This study investigates the clinical utility of BRAFV600E in cell-free DNA (cfDNA BRAFV600E) as a biomarker for real-time treatment monitoring in metastatic cases and for evaluating minimal residual disease (MRD) after curative resection. Methods: This single-center, prospective observational study included 37 patients with BRAFV600E-mutant CRC treated at Nippon Medical School Hospital between April 2017 and June 2024. Patients were divided into two cohorts: Cohort 1 (Stage IV cases): Evaluated cfDNA BRAFV600E for treatment monitoring. Cohort 2 (Stage I-III curatively resected cases): Assessed cfDNA BRAFV600E for recurrence risk prediction. Blood samples were collected before and during treatment and analyzed using droplet digital PCR (ddPCR) to measure cfDNA BRAFV600E levels. Results: Cohort 1 (Stage IV, n = 14): Pre-treatment cfDNA BRAFV600E was detected in 93% of cases. Patients with a decrease in cfDNA BRAFV600E variant allele frequency (VAF) after chemotherapy had significantly longer overall survival (511 vs. 189 days, p = 0.03) than those without a decrease. Cohort 2 (curatively resected, n = 23): cfDNA BRAFV600E was detected in 4/23 patients (17.4%) at 1 month post-surgery. cfDNA BRAFV600E showed better recurrence prediction compared to CEA (100% vs. 18.8%, p = 0.004). Among the seven patients who experienced recurrence, those with postoperative cfDNA BRAFV600E positivity had significantly shorter disease-free survival compared to cfDNA BRAFV600E-negative patients (179 vs. 840 days, p = 0.04). Conclusions: These findings support cfDNA BRAFV600E as a promising biomarker for monitoring treatment response and MRD detection in BRAFV600E-mutant CRC, reinforcing its role in guiding personalized treatment strategies and postoperative surveillance.

The efficacy of targeted therapy and/or immunotherapy with or without chemotherapy in patients with colorectal cancer: A network meta-analysis

BACKGROUND

The use of targeted drugs and immunotherapy has significantly impacted the treatment of Colorectal Cancer. However, horizontal comparison among various regimens is extremely rare. Therefore, we evaluated the survival efficacy of multiple treatment regimens of targeted therapy and/or immunotherapy with or without chemotherapy in patients with Colorectal Cancer.

METHODS

A systematic search was conducted in PubMed, EMBASE, and Cochrane databases, covering the period from the establishment of the databases to October 29, 2024. To obtain articles that met the inclusion and exclusion criteria and contained the required data for conducting a network meta-analysis (NMA). The NMA evaluated overall survival (OS) and progression-free survival (PFS).

RESULTS

A total of 90 studies were identified, comprising a sample size of 33,167 subjects. In terms of PFS, compared with simple chemotherapy strategies, most of the other single or combined strategies are significantly effective, among which targeted therapy strategies have more advantages. Encorafenib + Binimetinib + Cetuximab (ENC-BIN-CET) shows significant benefits in all comparisons except when compared with Chemotherapy + Cetuximab + Dalotuzumab (Chemo-CET-DAL), Encorafenib + Cetuximab (ENC-CET), and Panitumumab + Sotorasib (PAN-SOT). The ENC-CET and PAN-SOT targeted strategies also show significant benefits. Pembrolizumab (PEM) monotherapy has advantages over all others except when it is not superior to some targeted strategies. Chemotherapy + Bevacizumab + Atezolizumab is only inferior to some strategies. In terms of OS, the combinations of Chemotherapy + Bevacizumab, ENC-CET, Chemotherapy + Panitumumab, and ENC-BIN-CET are superior to simple chemotherapy regimens. ENC-BIN-CET shows OS benefits in all comparisons except some. ENC-CET significantly improves OS in most cases, and PEM also significantly improves OS in some regimens. In the probability ranking of OS and PFS, ENC-BIN-CET has the best effect, followed by ENC-CET.

CONCLUSIONS

In conclusion, pembrolizumab is still effective in prolonging survival. Dual- and triple-drug targeted strategies are the best in terms of OS and PFS, and the combination of targeted immunotherapy and chemotherapy also works. However, not all combinations are beneficial. As targeted drugs play an active role, specific drugs for colorectal cancer regimens should be carefully selected.

Expert consensus on the optimal management of BRAFV600E-mutant metastatic colorectal cancer in the Asia-Pacific region

The burden of colorectal cancer (CRC) is high in the Asia-Pacific region, and several countries in this region have among the highest and/or fastest growing rates of CRC in the world. A significant proportion of patients will present with or develop metastatic CRC (mCRC), and BRAFV600E-mutant mCRC represents a particularly aggressive phenotype that is less responsive to standard chemotherapies. In light of recent therapeutic advances, an Asia-Pacific expert consensus panel was convened to develop evidence-based recommendations for the diagnosis, treatment, and management of patients with BRAFV600E-mutant mCRC. The expert panel comprised nine medical oncologists from Australia, Hong Kong, Singapore, and Taiwan (the authors), who met to review current literature and develop eight consensus statements that describe the optimal management of BRAFV600E-mutant mCRC in the Asia-Pacific region. As agreed by the expert panel, the consensus statements recommend molecular testing at diagnosis to guide individualized treatment decisions, propose optimal treatment pathways according to microsatellite stability status, advocate for more frequent monitoring of BRAFV600E-mutant mCRC, and discuss local treatment strategies for oligometastatic disease. Together, these expert consensus statements are intended to optimize treatment and improve outcomes for patients with BRAFV600E-mutant mCRC in the Asia-Pacific region.

Comprehensive review of signaling pathways and therapeutic targets in gastrointestinal cancers

Targeted therapy, the milestone in the development of human medicine, originated in 2004 when the FDA approved the first targeted agent bevacizumab for colorectal cancer treatment. This new development has resulted from drug developers moving beyond traditional chemotherapy, and several trials have popped up in the last two decades with an unprecedented speed. Specifically, EGF/EGFR, VEGF/VEGFR, HGF/c-MET, and Claudin 18.2 therapeutic targets have been developed in recent years. Some targets previously thought to be undruggable are now being newly explored, such as the RAS site. However, the efficacy of targeted therapy is extremely variable, especially with the emergence of new drugs and the innovative use of traditional targets for other tumors in recent years. Accordingly, this review provides an overview of the major signaling pathway mechanisms and recent advances in targeted therapy for gastrointestinal cancers, as well as future perspectives.

"Undruggable KRAS": druggable after all

The three RAS genes (HRAS, KRAS, and NRAS) comprise the most frequently mutated oncogene family in cancer. KRAS is the predominant isoform mutated in cancer and is most prevalently mutated in major causes of cancer deaths including lung, colorectal, and pancreatic cancers. Despite extensive academic and industry efforts to target KRAS, it would take nearly four decades before approval of the first clinically effective KRAS inhibitors for the treatment of KRAS mutant lung cancer. We revisit past anti-KRAS strategies and painful lessons learned and then focus on the rapidly evolving landscape of direct RAS inhibitors, resistance mechanisms, and potential combination treatments.

Management of metastatic colorectal cancer: consensus in the Gulf Cooperation Council countries

Colorectal cancer (CRC) represents a major public health challenge globally, particularly in the Gulf Cooperation Council (GCC) countries, where it is identified as the second most prevalent form of cancer. Despite advancements in management strategies, tailored guidelines specific to the Gulf region are lacking. This paper presents consensus recommendations developed by a panel of experts from the GCC countries to address this gap. The guidelines cover epidemiology, screening, biomarkers, and treatment strategies for metastatic CRC. Treatment guidelines emphasize tailored approaches based on tumor characteristics, including sidedness and molecular profiles. Furthermore, the importance of maintenance therapy and emerging biomarkers are discussed. These guidelines aim to improve CRC management and outcomes in the Gulf region.

A Narrative Review of the Role of Immunotherapy in Metastatic Carcinoma of the Colon Harboring a BRAF Mutation

Patients affected by metastatic carcinoma of the colon/rectum (mCRC) harboring mutations in the BRAF gene (MBRAF) respond poorly to conventional therapy and have a prognosis worse than that of patients without mutations. Despite the promising outcomes of targeted therapy utilizing multi-targeted inhibition of the mitogen-activated protein kinase (MAPK) signaling system, the therapeutic efficacy, especially for the microsatellite stable/DNA proficient mismatch repair (MSS/PMMR) subtype, remains inadequate. Patients with MBRAF/mCRC and high microsatellite instability or DNA deficient mismatch repair (MSI-H/DMMR) exhibit a substantial tumor mutation burden, suggesting a high probability of response to immunotherapy. It is widely acknowledged that MSS/pMMR/mCRC is an immunologically "cold" malignancy that exhibits resistance to immunotherapy. The integration of targeted therapy and immunotherapy may enhance clinical outcomes in patients with MBRAF/mCRC. Efforts to enhance outcomes are exclusively focused on MSS/DMMR-BRAF mutant cancers, which constitute the largest proportion. This review evaluates the clinical efficacy and advancement of novel immune checkpoint blockade therapies for MSI-H/DMMR and MSS/PMMR BRAF mutant mCRC. We examine potential indicators in the tumor immune milieu for forecasting immunotherapeutic response in BRAF mutant mCRC.

Late-line options for patients with metastatic colorectal cancer: a review and evidence-based algorithm

Over the past few years, several novel systemic treatments have emerged for patients with treatment-refractory metastatic colorectal cancer, thus making selection of the most effective later-line therapy a challenge for medical oncologists. Over the past decade, regorafenib and trifluridine-tipiracil were the only available drugs and often provided limited clinical benefit compared to best supportive care. Results from subsequent practice-changing trials opened several novel therapeutic avenues, both for unselected patients (such as trifluridine-tipiracil plus bevacizumab or fruquintinib) and for subgroups defined by the presence of actionable alterations in their tumours (such as HER2-targeted therapies or KRASG12C inhibitors) or with no acquired mechanisms of resistance to the previously received targeted agents in circulating tumour DNA (such as retreatment with anti-EGFR antibodies). In this Review, we provide a comprehensive overview of advances in the field over the past few years and offer a practical perspective on translation of the most relevant results into the daily management of patients with metastatic colorectal cancer using an evidence-based algorithm. Finally, we discuss some of the most appealing ongoing areas of research and highlight approaches with the potential to further expand the therapeutic armamentarium.

The Evolving Role of Genomics in Colorectal Cancer

Approximately 75% of colorectal cancers (CRCs) harbour an identifiable driver mutation, 5% of which are heritable. These drivers have recognised implications for prognosis and therapy selection. In addition, potential germline mutations require investigations to inform testing of relatives, as well as surveillance for other malignancies. With increasing numbers of targeted drugs being approved, judicious testing is required to ensure sufficient tumour sample is available for testing and at the right point in the cancer pathway. Liquid biopsy with circulating tumour DNA (ctDNA) in the blood presents an exciting adjunct to tumour tissue testing for molecular drivers, as well as escalation and de-escalation of therapy. Here, we review the most frequent molecular alterations in CRC, how genomic testing should be integrated into the treatment pathway for CRC, and sources of further education.

An Evolving Landscape: New Therapies for Metastatic Colorectal Cancer

Substantial progress is being made in the development of novel therapies directed against colorectal cancer. The discovery of various molecular markers and advances in tumor profiling have facilitated the development of new targeted agents and immunotherapy. Not only have these drugs improved progression-free survival and even overall survival in some cases, but their related outcomes have also raised questions as to how to best combine or sequence therapies for even greater efficacy. Furthermore, we are beginning to understand how these combination therapies may yield for greater therapeutic response for patients with microsatellite stable colorectal cancer for which there is much need for improvement. In this article, we review recent trial data and explore the outcomes of various targeted therapies and immunotherapies for patient with advanced colorectal cancer.

First-Line Therapy in Metastatic, RAS Wild-Type, Left-Sided Colorectal Cancer: Should Everyone Receive Anti-EGFR Therapy?

PURPOSE OF REVIEW

This narrative review explores the efficacy and applicability of anti-EGFR therapy as the first-line treatment for patients with RAS wild-type (WT) left-sided metastatic colorectal cancer (mCRC). It critically examines current guidelines, along with recent evidence in the literature, to assess whether it should be universally applied.

RECENT FINDINGS

Recent evidences highlight the variability of the response to anti-EGFR therapies due to molecular diversity and several clinical factors, such as RAS mutational status and primary tumor location. Anti-EGFR plus chemotherapy is the standard first-line treatment for most patients with MSS, RAS-WT, left-sided mCRC. Whether this combination is the best treatment for these patients remains an open question. This review delves into the role of EGFR inhibition in mCRC, focusing on clinical factors and the knowledge of biology, molecular targets, and biomarkers. It underscores the crucial role of a personalized approach, empowering healthcare providers and equipping them with the confidence to make informed decisions.

BRAFV600E-Mutant Metastatic Colorectal Cancer: Current Evidence, Future Directions, and Research Priorities

BRAFV600E-mutant metastatic colorectal cancer represents a distinct molecular phenotype known for its aggressive biological behavior, resistance to standard therapies, and poor survival rates. Improved understanding of the biology of the BRAF oncogene has led to the development of targeted therapies that have paved the way for a paradigm shift in managing this disease. However, despite significant recent advancements, responses to targeted therapies are short-lived, and several challenges remain. In this review, we discuss how progress in treating BRAFV600E-mutant metastatic colorectal cancer has been made through a better understanding of its unique biological and clinical features. We provide an overview of the evidence to support current treatment approaches and discuss critical areas of need and future research strategies that hold the potential to refine clinical practice further. We also discuss some challenging aspects of managing this disease, particularly the complexity of acquired resistance mechanisms that develop under the selective pressure of targeted therapies and rational strategies being investigated to overcome them.

Targeting the EGFR signalling pathway in metastatic colorectal cancer

Epidermal growth factor receptor (EGFR) and its activated downstream signalling pathways play a crucial role in colorectal cancer development and progression. After four decades of preclinical, translational, and clinical research, it has been shown that blocking the EGFR signalling pathway at different molecular levels represents a fundamental therapeutic strategy for patients with metastatic colorectal cancer. Nevertheless, the efficacy of molecularly targeted therapies is inescapably limited by the insurgence of mechanisms of acquired cancer cell resistance. Thus, in the era of precision medicine, a deeper understanding of the complex molecular landscape of metastatic colorectal cancer is required to deliver the best treatment choices to all patients. Major efforts are currently ongoing to improve patient selection, improve the efficacy of available treatments targeting the EGFR pathway, and develop novel combination strategies to overcome therapy resistance within the continuum of care of metastatic colorectal cancer.

A comprehensive overview of the molecular features and therapeutic targets in BRAFV600E-mutant colorectal cancer

As one of the most prevalent digestive system tumours, colorectal cancer (CRC) poses a significant threat to global human health. With the emergence of immunotherapy and target therapy, the prognosis for the majority of CRC patients has notably improved. However, the subset of patients with BRAF exon 15 p.V600E mutation (BRAFV600E) has not experienced remarkable benefits from these therapeutic advancements. Hence, researchers have undertaken foundational investigations into the molecular pathology of this specific subtype and clinical effectiveness of diverse therapeutic drug combinations. This review comprehensively summarised the distinctive molecular features and recent clinical research advancements in BRAF-mutant CRC. To explore potential therapeutic targets, this article conducted a systematic review of ongoing clinical trials involving patients with BRAFV600E-mutant CRC.

Complete response of metastatic microsatellite-stable BRAF V600E colorectal cancer to first-line oxaliplatin-based chemotherapy and immune checkpoint blockade

The randomized METIMMOX trial (NCT03388190) examined if patients with previously untreated, unresectable abdominal metastases from microsatellite-stable (MSS) colorectal cancer (CRC) might benefit from potentially immunogenic, short-course oxaliplatin-based chemotherapy alternating with immune checkpoint blockade (ICB). Three of 38 patients assigned to this experimental treatment had metastases from BRAF-mutant MSS-CRC, in general a poor-prognostic subgroup explored here. The ≥70-year-old females presented with ascending colon adenocarcinomas with intermediate tumor mutational burden (6.2-11.8 mutations per megabase). All experienced early disappearance of the primary tumor followed by complete response of all overt metastatic disease, resulting in progression-free survival as long as 20-35 months. However, they encountered recurrence at previously unaffected sites and ultimately sanctuary organs, or as intrahepatic tumor evolution reflected in the terminal loss of initially induced T-cell clonality in liver metastases. Yet, the remarkable first-line responses to short-course oxaliplatin-based chemotherapy alternating with ICB may offer a novel therapeutic option to a particularly hard-to-treat MSS-CRC subgroup.

Current and Emerging Treatment Paradigms in Colorectal Cancer: Integrating Hallmarks of Cancer

The treatment of unresectable metastatic colorectal cancer has evolved over the last two decades, as knowledge of cancer biology has broadened and new targets have emerged. 'The Hallmarks of Cancer' illustrate the crucial capabilities acquired by cells to become malignant and represent the evolution of knowledge of tumor biology. This review integrates these novel targets and therapies into selected hallmarks: sustaining proliferative signaling, inducing vasculature, avoiding immune destruction, genome instability and mutation, reprogramming cellular metabolism, and resisting cell death. The different strategies and combinations under study are based on treatments with anti-EGFR, anti-VEGF, and anti-HER2 agents, KRAS G12C inhibitors, BRAF and MEK inhibitors, and immune checkpoint inhibitors. However, new approaches are emerging, including vaccines, WEE1 inhibitors, and PARP inhibitors, among others. The further deciphering of cancer biology will unravel new targets, develop novel therapies, and improve patients' outcomes.

Therapeutic strategies targeting the epidermal growth factor receptor signaling pathway in metastatic colorectal cancer

More than 1.9 million new colorectal cancer (CRC) cases and 935000 deaths were estimated to occur worldwide in 2020, representing about one in ten cancer cases and deaths. Overall, colorectal ranks third in incidence, but second in mortality. More than half of the patients are in advanced stages at diagnosis. Treatment options are complex because of the heterogeneity of the patient population, including different molecular subtypes. Treatments have included conventional fluorouracil-based chemotherapy, targeted therapy, immunotherapy, etc. In recent years, with the development of genetic testing technology, more and more targeted drugs have been applied to the treatment of CRC, which has further prolonged the survival of metastatic CRC patients.

BRAF V600E-mutant colorectal cancer with CNS metastases treated successfully with encorafenib, binimetinib and cetuximab

This report describes a case of BRAF V600E-mutated colorectal cancer with CNS metastases in which treatment with encorafenib, binimetinib and cetuximab was effective. There is limited information on the ability of encorafenib, binimetinib and cetuximab to enter the CNS.The patient was a 53-year-old man was diagnosed with ascending colon cancer (cT3N3M1c stage IVc). BRAF V600E mutation was confirmed. FOLFOX was started, but CNS metastases soon appeared. Encorafenib, binimetinib and cetuximab were administered and had a favorable effect on the CNS lesions. The patient initially responded well, but his disease progressed 2 months later. Further research is needed to improve management strategies for BRAF V600E-mutated colorectal cancer with CNS metastases.

Epidermal growth factor receptor antagonists in colorectal cancer: emerging strategies for precision therapy

INTRODUCTION

The global prevalence of colorectal cancer highlights the need to enhance treatment strategies for improved patient outcomes. The pivotal role of epidermal growth factor receptor (EGFR) signaling in regulating cellular processes for this disease pinpoints its value as a therapeutic target, despite the emergence of resistance mechanisms over time.

AREAS COVERED

This review discusses the clinical evidence supporting the use of EGFR inhibitors in molecularly-selected patients based on molecular characteristics (notably BRAF V600E and KRAS G12C) including combination approaches targeting different points in in the signaling pathway, as well as strategies such as EGFR inhibitor rechallenge. The role of HER2 inhibitors and emerging approaches such as bispecific antibodies are also reviewed.

EXPERT OPINION

Recently, inhibitors targeting the KRAS G12C variant have emerged, albeit with modest monotherapy activity compared to other tumor types, emphasizing the influence of histologic origins on the EGFR signaling pathway. Integration of EGFR inhibitors into precision medicine has facilitated tailored therapies addressing resistance mechanisms. Patient selection for EGFR inhibitor rechallenge guided by ctDNA findings is crucial, with ongoing investigations exploring novel combinations to enhance EGFR blockade, highlighting the transformative potential of precision medicine in shaping the future of mCRC treatment toward personalized and targeted approaches.

First-line oxaliplatin-based chemotherapy and nivolumab for metastatic microsatellite-stable colorectal cancer-the randomised METIMMOX trial

BACKGROUND

We evaluated first-line treatment of metastatic microsatellite-stable colorectal cancer with short-course oxaliplatin-based chemotherapy alternating with immune checkpoint blockade.

METHODS

Patients were randomly assigned to chemotherapy (the FLOX regimen; control group) or alternating two cycles each of FLOX and nivolumab (experimental group). Radiographic response assessment was done every eight weeks with progression-free survival (PFS) as the primary endpoint. Cox proportional-hazards regression models estimated associations between PFS and relevant variables. A post hoc analysis explored C-reactive protein as signal of responsiveness to immune checkpoint blockade.

RESULTS

Eighty patients were randomised and 38 in each group received treatment. PFS was comparable-control group: median 9.2 months (95% confidence interval (CI), 6.3-12.7); experimental group: median 9.2 months (95% CI, 4.5-15.0). The adjusted Cox model revealed that experimental-group subjects aged ≥60 had significantly lowered progression risk (p = 0.021) with hazard ratio 0.17 (95% CI, 0.04-0.76). Experimental-group patients with C-reactive protein <5.0 mg/L when starting nivolumab (n = 17) reached median PFS 15.8 months (95% CI, 7.8-23.7). One-sixth of experimental-group cases (all KRAS/BRAF-mutant) achieved complete response.

CONCLUSIONS

The investigational regimen did not improve the primary outcome for the intention-to-treat population but might benefit small subgroups of patients with previously untreated, metastatic microsatellite-stable colorectal cancer.

TRIAL REGISTRATION

ClinicalTrials.gov number, NCT03388190 (02/01/2018).

State-of-the-Art Management of Colorectal Cancer: Treatment Advances and Innovation

Colorectal cancer (CRC) remains a significant global health challenge, ranking among the leading causes of cancer-related morbidity and mortality worldwide. Recent advancements in molecular characterization have revolutionized our understanding of the heterogeneity within colorectal tumors, particularly in the context of tumor sidedness. Tumor sidedness, referring to the location of the primary tumor in either the right or left colon, has emerged as a critical factor influencing prognosis and treatment responses in metastatic CRC. Molecular underpinnings of CRC, the impact of tumor sidedness, and how this knowledge guides therapeutic decisions in the era of precision medicine have led to improved outcomes and better quality of life in patients. The emergence of circulating tumor DNA as a prognostic and predictive tool in CRC heralds promising advancements in the diagnosis and monitoring of the disease. This innovation facilitates better patient selection for exploration of additional treatment options. As the field progresses, with investigational agents demonstrating potential as future treatments for refractory metastatic CRC, new avenues for enhancing outcomes in this challenging disease are emerging.

Current advances in targeted therapy for metastatic colorectal cancer - Clinical translation and future directions

The last two decades have witnessed major breakthroughs in the development of targeted therapy for patients with metastatic colorectal cancer (mCRC), an achievement which stems largely from advances in translational research. Precision medicine is now widely practiced in routine oncological care, where systemic therapy is individualized based on clinical factors such as primary tumor sidedness, location and number of metastases, as well as molecular factors such as the RAS and BRAF mutation status, mismatch repair / microsatellite status and presence of other actionable genomic alterations in the tumor. The optimal selection of patients with RAS and BRAF-wild type (WT), left-sided primary tumor for treatment with epidermal growth factor receptor (EGFR) and chemotherapy (chemo) has markedly improved survival in the first-line setting. The pivotal trials of cetuximab in combination with BRAF/ MEK inhibitor for BRAF V600E mutant mCRC, and panitumumab with KRAS G12C inhibitor in KRAS(G12C)-mutant mCRC have been practice-changing. Anti-HER2 small molecular inhibitor, antibodies and antibody-drug conjugates have significantly improved the treatment outcome of patients with HER2 amplified mCRC. Anti-angiogenesis agents are now used across all lines of treatment and novel combinations with immune-checkpoint inhibitors are under active investigation in MSS mCRC. The non-invasive monitoring of molecular resistance to targeted therapies using Next Generation Sequencing analysis of circulating tumor-derived DNA (ctDNA) and captured sequencing of tumors have improved patient selection for targeted therapies. This review will focus on how latest advances, challenges and future directions in the development of targeted therapies in mCRC.

New clinical trial design in precision medicine: discovery, development and direction

In the era of precision medicine, it has been increasingly recognized that individuals with a certain disease are complex and different from each other. Due to the underestimation of the significant heterogeneity across participants in traditional "one-size-fits-all" trials, patient-centered trials that could provide optimal therapy customization to individuals with specific biomarkers were developed including the basket, umbrella, and platform trial designs under the master protocol framework. In recent years, the successive FDA approval of indications based on biomarker-guided master protocol designs has demonstrated that these new clinical trials are ushering in tremendous opportunities. Despite the rapid increase in the number of basket, umbrella, and platform trials, the current clinical and research understanding of these new trial designs, as compared with traditional trial designs, remains limited. The majority of the research focuses on methodologies, and there is a lack of in-depth insight concerning the underlying biological logic of these new clinical trial designs. Therefore, we provide this comprehensive review of the discovery and development of basket, umbrella, and platform trials and their underlying logic from the perspective of precision medicine. Meanwhile, we discuss future directions on the potential development of these new clinical design in view of the "Precision Pro", "Dynamic Precision", and "Intelligent Precision". This review would assist trial-related researchers to enhance the innovation and feasibility of clinical trial designs by expounding the underlying logic, which be essential to accelerate the progression of precision medicine.

Liquid biopsy in colorectal cancer: Onward and upward

Colorectal cancer (CRC) remains a leading cause of cancer-related deaths worldwide. In recent years, liquid biopsy has emerged as one of the most interesting areas of research in oncology, leading to innovative trials and practical changes in all aspects of CRC management. RNAs and cell free DNA (cfDNA) methylation are emerging as promising biomarkers for early diagnosis. Post-surgical circulating tumour DNA (ctDNA) can aid in evaluating minimal residual disease and personalising adjuvant treatment. In rectal cancer, ctDNA could improve response assessment to neoadjuvant therapy and risk stratification, especially in the era of organ-preservation trials. In the advanced setting, ctDNA analysis offers the opportunity to monitor treatment response and identify driver and resistance mutations more comprehensively than traditional tissue analysis, providing prognostic and predictive information. The aim of this review is to provide a detailed overview of the clinical applications and future perspectives of liquid biopsy in CRC.

Cetuximab as a Key Partner in Personalized Targeted Therapy for Metastatic Colorectal Cancer

Cetuximab, a chimeric IgG1 monoclonal antibody targeting the epidermal growth factor receptor (EGFR), has revolutionized personalized treatment of metastatic colorectal cancer (mCRC) patients. This review highlights the mechanism of action, characteristics, and optimal indications for cetuximab in mCRC. Cetuximab has emerged as a pivotal partner for novel therapies in specific molecular subgroups, including BRAF V600E, KRAS G12C, and HER2-altered mCRC. Combining cetuximab with immunotherapy and other targeted agents further expands the therapeutic landscape, offering renewed hope for mCRC patients who face the development of resistance to conventional therapies. Ongoing clinical trials have continued to uncover innovative cetuximab-based treatment strategies, promising a brighter future for mCRC patients. This review provides a comprehensive overview of cetuximab's role and its evolving importance in personalized targeted therapy of mCRC patients, offering valuable insights into the evolving landscape of colorectal cancer treatment.

Molecular Targeting of the BRAF Proto-Oncogene/Mitogen-Activated Protein Kinase (MAPK) Pathway across Cancers

The mitogen-activated protein kinase (MAPK) pathway is essential for cellular proliferation, growth, and survival. Constitutive activation of this pathway by BRAF mutations can cause downstream activation of kinases, leading to uncontrolled cellular growth and carcinogenesis. Therefore, inhibition of BRAF and the downstream substrate MEK has been shown to be effective in controlling tumor growth and proliferation. Over the last decade, several BRAF and MEK inhibitors have been investigated, ranging from primarily melanoma to various cancer types with BRAF alterations. This subsequently led to several Food and Drug Administration (FDA) approvals for BRAF/MEK inhibitors for melanoma, non-small cell lung cancer, anaplastic thyroid cancer, colorectal cancer, histiocytosis neoplasms, and finally, tumor-agnostic indications. Here, this comprehensive review will cover the developments of BRAF and MEK inhibitors from melanomas to tumor-agnostic indications, novel drugs, challenges, future directions, and the importance of those drugs in personalized medicine.

BRAF Inhibitors in BRAF-Mutated Colorectal Cancer: A Systematic Review

Colorectal cancer (CRC) is the second-leading cause of cancer-related deaths globally. BRAF mutation is present in about 10% of CRC patients and is associated with a poor response to chemotherapy. These patients have a relatively poor prognosis. This review aims to assess the efficacy and safety of BRAF inhibitors in BRAF-mutated CRC patients. A literature search was performed on PubMed and Embase, and clinical trials relevant to BRAF inhibitors in CRC were included. Data were extracted for efficacy and safety variables. Two randomized clinical trials (n = 765) and eight non-randomized trials (n = 281) were included based on inclusion criteria. In RCTs, an overall response was reported in 23% of the patients treated with BRAF inhibitor-based regimens compared to 2.5% with control regimens. The hazard ratio of overall survival was also significantly better with triplet encorafenib therapy at 0.52 (95% CI = 0.39-0.70). In single-arm trials, ORR was 17% and 34% in two-drug and three-drug regimens, respectively. BRAF inhibitor-based regimens were safe and effective in the treatment of BRAF-mutated CRC. Large-scale randomized trials are needed to find a suitable population for each regimen. PROSPERO registration No. CRD42023471627.

CRISPR-Cas System Is an Effective Tool for Identifying Drug Combinations That Provide Synergistic Therapeutic Potential in Cancers

Despite numerous efforts, the therapeutic advancement for neuroblastoma and other cancer treatments is still ongoing due to multiple challenges, such as the increasing prevalence of cancers and therapy resistance development in tumors. To overcome such obstacles, drug combinations are one of the promising applications. However, identifying and implementing effective drug combinations are critical for achieving favorable treatment outcomes. Given the enormous possibilities of combinations, a rational approach is required to predict the impact of drug combinations. Thus, CRISPR-Cas-based and other approaches, such as high-throughput pharmacological and genetic screening approaches, have been used to identify possible drug combinations. In particular, the CRISPR-Cas system (Clustered Regularly Interspaced Short Palindromic Repeats) is a powerful tool that enables us to efficiently identify possible drug combinations that can improve treatment outcomes by reducing the total search space. In this review, we discuss the rational approaches to identifying, examining, and predicting drug combinations and their impact.

Clinical research progress on BRAF V600E-mutant advanced colorectal cancer

Colorectal cancer is one of the malignant tumors that pose a serious threat to human health. A particularly bad prognosis might be expected for colorectal tumors with the unique molecular subtype BRAF V600E mutation. With the development of precision therapy, the advent of molecularly targeted therapies and immune checkpoint inhibitors has improved the outcome of intermediate to advanced colorectal cancer. However, the duration of drug benefit is usually short, and overall survival and progression-free survival remain suboptimal. Therefore, investigators are exploring more rational, safe, and effective drug combination regimens through clinical trials to provide longer survival for patients with such genetic mutations with metastatic colorectal cancer (mCRC). This article reviews the progress of clinical research on molecularly targeted drugs, immune checkpoint inhibitors, first-line chemotherapeutic agents, and different combination therapy regimens (including different targeted drug combinations, immune combination targeting, and chemotherapy combination targeting) for colorectal cancer patients with BRAF V600E mutation, which provides a reference for further in-depth clinical exploration of the treatment of colorectal cancer patients with BRAF V600E mutation.

BRAF Inhibitors in Metastatic Colorectal Cancer and Mechanisms of Resistance: A Review of the Literature

Metastatic colorectal cancer (mCRC) with mutated BRAF exhibits distinct biological and molecular features that set it apart from other subtypes of CRC. Current standard treatment for these tumors involves a combination of chemotherapy (CT) and VEGF inhibitors. Recently, targeted therapy against BRAF and immunotherapy (IT) for cases with microsatellite instability (MSI) have been integrated into clinical practice. While targeted therapy has shown promising results, resistance to treatment eventually develops in a significant portion of responsive patients. This article aims to review the available literature on mechanisms of resistance to BRAF inhibitors (BRAFis) and potential therapeutic strategies to overcome them.

Identification of an optimal mutant allele frequency to detect activating KRAS, NRAS, and BRAF mutations in a commercial cell-free DNA next-generation sequencing assay in colorectal and pancreatic adenocarcinomas

Background

Evaluation for activating mutations in KRAS, NRAS, and BRAF in colorectal cancer (CRC) and in KRAS in pancreatic ductal adenocarcinoma (PDAC) is essential for clinical care. Plasma cell-free DNA (cfDNA) next-generation sequencing (NGS) allows convenient assessment of a tumor's molecular profile, however low tumor DNA shedding limits sensitivity. We investigated mutant allele frequency (MAF) of other oncogenic dominant genes to identify a threshold for accurate detection of KRAS, NRAS, and BRAF (RAS/RAF) mutations in cfDNA.

Methods

Molecular and clinical data were obtained from the Duke Molecular Registry of Tumors and the SCRUM-Japan GOZILA study. Patients with CRC or PDAC and a KRAS, NRAS, or BRAF activating single nucleotide variant (SNV) present on tissue NGS and with available cfDNA assays were included. Recursive partitioning and Wilcoxon-rank statistics methods identified potential cut-points for discriminative MAF values.

Results

One hundred and thirty-five CRC and 30 PDAC cases with 198 total cfDNA assays met criteria. Greatest non-RAS/RAF dominant gene MAF of 0.34% provided maximum discrimination for predicting RAS/RAF SNV detection. Sensitivity for RAS/RAF SNVs increased with dominant gene MAF, with MAF ≥1% predicting sensitivity >98%, MAF between 0.34 and 1% predicting sensitivity of 84.0%, and MAF £0.34% predicting sensitivity of 50%. For 43 cfDNA assays that did not detect RAS/RAF SNVs, 18 assays detected 34 other oncogenic variants, of which 80.6% were not also detected on tissue.

Conclusions

Non-RAS/RAF dominant oncogenic mutation MAF ≥1% on cfDNA NGS predicts high sensitivity to detect RAS/RAF oncogenic SNVs in CRC and PDAC. MAF £0.34% indicates an assay may not reliably detect RAS/RAF SNVs, despite detection on tissue testing. Most variants from assays that did not detect RAS/RAF had MAF <1% and were not detected on tissue, suggesting potential confounding. These data suggest a practical approach to determining cfDNA assay adequacy, with implications for guiding clinical decisions in CRC and PDAC.

Optimizing the first-line treatment for metastatic colorectal cancer

Colorectal cancer represents an important oncological challenge both for its incidence, which makes it an important health problem, and for its biological complexity, which has made clinical results very difficult in terms of outcome for this category of patients. To date these diseases should not be treated as a single entity but it is necessary to distinguish colorectal cancers based on characteristics that nowadays are essential to have greater therapeutic benefits. These include the sideness of the disease, the state of microsatellites, the presence of prognostic and predictive mutations of response to treatments currently available in clinical practice, which are associated with new therapeutic targets. The greatest challenge in the future will be to circumvent the resistance mechanisms that make this disease very difficult to treat with good long-term results by studying effective combination treatments with a good toxicity profile. Once such combinations or targeted treatments are consolidated, it will be desirable to shift the best therapies to the first line treatment to make them immediately accessible to the patient. It will also be essential to refine the selection of patients who can benefit from these treatments.

Unravelling the Complexity of Colorectal Cancer: Heterogeneity, Clonal Evolution, and Clinical Implications

Colorectal cancer (CRC) is a global health concern and a leading cause of death worldwide. The disease's course and response to treatment are significantly influenced by its heterogeneity, both within a single lesion and between primary and metastatic sites. Biomarkers, such as mutations in KRAS, NRAS, and BRAF, provide valuable guidance for treatment decisions in patients with metastatic CRC. While high concordance exists between mutational status in primary and metastatic lesions, some heterogeneity may be present. Circulating tumor DNA (ctDNA) analysis has proven invaluable in identifying genetic heterogeneity and predicting prognosis in RAS-mutated metastatic CRC patients. Tumor heterogeneity can arise from genetic and non-genetic factors, affecting tumor development and response to therapy. To comprehend and address clonal evolution and intratumoral heterogeneity, comprehensive genomic studies employing techniques such as next-generation sequencing and computational analysis are essential. Liquid biopsy, notably through analysis of ctDNA, enables real-time clonal evolution and treatment response monitoring. However, challenges remain in standardizing procedures and accurately characterizing tumor subpopulations. Various models elucidate the origin of CRC heterogeneity, highlighting the intricate molecular pathways involved. This review focuses on intrapatient cancer heterogeneity and genetic clonal evolution in metastatic CRC, with an emphasis on clinical applications.

Beyond EGFR inhibitors in advanced colorectal cancer: Targeting BRAF and HER2

The addition of antiepidermal growth factor receptor (EGFR) monoclonal antibodies, cetuximab or panitumumab, to conventional chemotherapy has improved clinical outcomes for rat sarcoma virus (RAS) wild-type advanced colorectal cancer patients, however, durable responses and 5-year overall survival rates remain limited. BRAF V600E somatic mutation and human epidermal growth factor receptor (HER2) amplification/overexpression have been separately implicated in primary resistance to anti-EGFR therapeutic strategies via aberrant activation of the mitogen-activated protein kinase (MAPK) signaling pathway, resulting in poorer outcomes. In addition to being a negative predictive biomarker for anti-EGFR therapy, BRAF V600E mutation and HER2 amplification/overexpression serve as positive predictors of response to therapies targeting these respective tumor promoters. This review will highlight key clinical studies that support the rational use of v-Raf murine sarcoma viral oncogene homolog B1 (BRAF) and HER2-targeted therapies, often in combination with other targeted agents, cytotoxic chemotherapy, and immune checkpoint inhibitors. We discuss current challenges with BRAF and HER2-targeted therapies in metastatic colorectal cancer and potential opportunities for improvement.

The Effects of Statins, Ezetimibe, PCSK9-Inhibitors, Inclisiran, and Icosapent Ethyl on Platelet Function

This review aims to examine the complex interaction between dyslipidemia, platelet function, and related drug treatments. In particular, the manuscript provides an overview of the effects of major hypolipidemic drugs on platelet function. Indeed, growing evidence supports the view that statins, ezetimibe, PCSK9 inhibitors, inclisiran, and icosapent ethyl also act as antithrombotics. It is known that platelets play a key role not only in the acute phase of coronary syndromes but also in the early phase of atherosclerotic plaque formation. The goal of cholesterol-lowering therapy is to reduce cardiovascular events. The direct effects of cholesterol-lowering drugs are widely described in the literature. Lowering LDL-c (low-density lipoprotein cholesterol) by 1 mmol/L results in a 22-23% reduction in cardiovascular risk. Numerous studies have examined the direct antithrombotic effects of these drugs on platelets, endothelium, monocytes, and smooth muscle cells, and thus, potentially independent of blood LDL-cholesterol reduction. We reviewed in vitro and in vivo studies evaluating the complex interaction between hypercholesterolemia, hypertriglyceridemia, platelet function, and related drug treatments. First, we discussed the role of statins in modulating platelet activation. Discontinuation of statin therapy was associated with increased cardiovascular events with increased ox-LDL, P-selectin, and platelet aggregation. The effect of PCSK9-I (inhibitors of proprotein convertase subtilisin/kexin type 9, PCSK9 involved in the degradation of LDL receptors in the liver) was associated with a statistically significant reduction in platelet reactivity, calculated in P2Y12 reaction units (PRU), in the first 14 days and no difference at 30 days compared to placebo. Finally, in patients with hypertriglyceridemia, the REDUCE-IT study showed that icosapent ethyl (an ethyl ester of eicosapentaenoic acid that reduces triglyceride synthesis and improves triglyceride clearance) resulted in a 25% reduction in ischemic events and cardiovascular death. However, to date, there is not yet clear clinical evidence that the direct antithrombotic effects of the drugs may have a beneficial impact on outcomes independently from the reduction in LDL-C or triglycerides.

Strategic Insight into the Combination Therapies for Metastatic Colorectal Cancer

Colorectal cancer (CRC) is the second most common cause of cancer-related deaths worldwide. The 5-year survival rate after curative resection is almost 80%, however, it is still less than satisfactory for metastatic CRC (mCRC). The combination approach including surgery, chemotherapy, molecular targeted therapy, and immunotherapy is a promising strategy due to its synergistic anticancer effect. Moreover, circulating tumor DNA (ctDNA) analysis has been reported to stratify the post-operative risk of recurrence, thus providing clinically valuable information for deciding to conduct adjuvant chemotherapy. Furthermore, multiple new drugs that potentially target undruggable genes, including KRAS, have been developed. In this review, we discuss the current management of patients with mCRC and future perspectives in the light of a combination therapeutic strategy.

Treatment of BRAF-V600E mutant metastatic colorectal cancer: new insights and biomarkers

INTRODUCTION

The presence of a BRAF-V600E mutation in metastatic colorectal cancer (mCRC) is observed in approximately 12% of cases and is associated with poor prognosis and aggressive disease. Unlike melanoma, the development of successful BRAF blockade in colorectal cancer has been complex. The phase III BEACON trial made significant progress in the development of BRAF inhibitors by establishing encorafenib-cetuximab as the new standard of care for patients with mCRC who have progressed to one or two previous lines of treatment. Nonetheless, not all patients respond to encorafenib-based combinations, and some responses are short-lived. Identifying new strategies to boost antitumor activity and improve survival is paramount.

AREAS COVERED

The development of targeted therapy for BRAF-V600E mCRC starting with BRAF inhibitors as monotherapy through novel combinations with anti-VEGF or anti-PD1 agents to enhance antitumor activity is reviewed, with a particular focus on the development of predictive and prognostic biomarkers.

EXPERT OPINION

There is a crucial need to better understand tumor biology and develop accurate and reliable biomarkers to enhance the antitumor activity of encorafenib-based combinations. The RNF43 mutation is an accurate and reliable predictive biomarker of response, and combinations that target crosstalk between the MAPK pathway, the immune system, and WNT pathways seem promising.

The BEETS (JACCRO CC-18) trial: an observational and translational study of BRAF-mutated metastatic colorectal cancer

For BRAF V600E-mutated metastatic colorectal cancer (mCRC), the BEACON phase 3 trial showed survival benefit of triplet therapy with cetuximab (anti-EGFR antibody), encorafenib (BRAF inhibitor) and binimetinib (MEK inhibitor) as well as doublet therapy with cetuximab and encorafenib over irinotecan-based chemotherapy plus anti-EGFR antibody. Both regimens are standards of care in Japan, but definite biomarkers for predicting efficacy and selecting treatment remain lacking. The mechanisms underlying resistance to these regimens also warrant urgent exploration to further evolve treatment. This prospective observational/translational study evaluated real-word clinical outcomes with cetuximab and encorafenib with or without binimetinib for BRAF-mutated mCRC patients and investigated biomarkers for response and resistance by collecting blood samples before and after treatment. Clinical Trial Registration: UMIN000045530 (https://center6.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000051983).