BRAF Mutations: The Discovery of Allele- and Lineage-Specific Differences

Background: Anti-EGFR monoclonal antibodies (mAbs) have become a relevant solution for the treatment of patients with metastatic colorectal cancer. Current anti-EGFR monoclonal antibodies face a series of problems, including resistance and non-durable response, and RAS and BRAF mutations serve as exclusion criteria for treatment with anti-EGFR mAbs. Advances in molecular tumor profiling and information on subsequent pathways responsible for disease progression and drug resistance helped develop a new generation of anti-EGFR mAbs. These second-generation mAbs have been developed to overcome existing resistance mechanisms and to limit common side effects. For the moment, existing literature suggests that these novel anti-EGFR mAbs are far from finding their way to clinical practice soon. Objective: In this review, we summarize and evaluate current data regarding ongoing research and completed clinical trials for different second-generation anti-EGFR monoclonal antibodies. Conclusion: Anti-EGFR mAbs exhibit efficacy in advanced colorectal cancer, but second-generation mAbs failed to prove their benefit in the treatment of metastatic colorectal cancer. Understanding the biological basis of primary and acquired drug resistance could allow scientists to design better clinical trials and develop improved second-generation mAbs.

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Predictive and prognostic biomarkers with therapeutic targets in colorectal cancer: A 2021 update on current development, evidence, and recommendation

Journal of Oncology Pharmacy Practice ◽

10.1177/10781552211005525 ◽

2021 ◽

pp. 107815522110055

Author(s):

Clement Chung

Keyword(s):

Checkpoint Inhibitors ◽

Therapeutic Targets ◽

Growth Factor Receptor ◽

Predictive Biomarkers ◽

Tumor Location ◽

Prognostic Biomarkers ◽

Her2 Gene ◽

Braf Mutations ◽

Therapeutic Implications ◽

Molecular Alterations

Although therapeutically actionable molecular alterations are widely distributed across many cancer types, only a handful of them show evidence of clinical utility and are recommended for routine clinical practice in the management of cancers of colon and rectum (CRC). This 2021 update aims to provide a succinct summary on the use of prognostic and/or predictive biomarkers (expanded RAS, BRAF, microsatellite-high [MSI-H] or deficient mismatch repair [dMMR], neurotrophic tyrosine receptor kinase [ NTRK] fusion genes, and human epidermal growth factor receptor type II [ HER2] gene amplification) associated with CRC. Therapeutic implications of each relevant predictive or prognostic biomarker for patients with CRC are described, along with discussion on new developments on (1) biomarker-driven therapies such as testing of BRAF, MLH1 promoter methylation and MMR germline genes in differentiating sporadic CRC or hereditary conditions such as Lynch syndrome; (2) first-line use of immune checkpoint inhibitors in metastatic CRC; (3) risk stratification and therapy selection based on primary tumor location (left-sided vs. right-sided colon cancer); (3) atypical BRAF mutations; (4) use of EGFR directed therapy in the perioperative oligometastatic disease setting; (5) re-challenge of EGFR directed therapy and (6) personalizing therapy of fluoropyrimidine and irinotecan based on new evidence in pharmacogenomic testing. Data are collected and analyzed from available systematic reviews and meta-analyses of treatments with known therapeutic targets in CRC, which may be associated with predictive and/or prognostic biomarkers. Discussions are presented in an application-based format, with goal to empower pharmacists or other clinicians to gain awareness and understanding in biomarker-driven cancer therapy issues.

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P76.90 Molecular Characteristics of BRAF Mutations in EGFR Mutant NSCLC after Progression on EGFR TKIs and Response to Combination Targeted Therapy

Journal of Thoracic Oncology ◽

10.1016/j.jtho.2021.01.1147 ◽

2021 ◽

Vol 16 (3) ◽

pp. S628-S629

Author(s):

W. Fang ◽

J. Hu ◽

Y. Huang ◽

C. Xu ◽

W. Wang ◽

...

Keyword(s):

Targeted Therapy ◽

Molecular Characteristics ◽

Braf Mutations ◽

Egfr Mutant ◽

Egfr Tkis

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Evidence-Based Second-Line Treatment in RAS Wild-Type/Mutated Metastatic Colorectal Cancer in the Precision Medicine Era

International Journal of Molecular Sciences ◽

10.3390/ijms22147717 ◽

2021 ◽

Vol 22 (14) ◽

pp. 7717

Author(s):

Guido Giordano ◽

Pietro Parcesepe ◽

Giuseppina Bruno ◽

Annamaria Piscazzi ◽

Vincenzo Lizzi ◽

...

Keyword(s):

Colorectal Cancer ◽

Metastatic Colorectal Cancer ◽

Checkpoint Inhibitors ◽

Line Treatment ◽

Second Line ◽

Wild Type ◽

First Line ◽

Braf Mutations ◽

Mutational Status ◽

First Line Treatment

Target-oriented agents improve metastatic colorectal cancer (mCRC) survival in combination with chemotherapy. However, the majority of patients experience disease progression after first-line treatment and are eligible for second-line approaches. In such a context, antiangiogenic and anti-Epidermal Growth Factor Receptor (EGFR) agents as well as immune checkpoint inhibitors have been approved as second-line options, and RAS and BRAF mutations and microsatellite status represent the molecular drivers that guide therapeutic choices. Patients harboring K- and N-RAS mutations are not eligible for anti-EGFR treatments, and bevacizumab is the only antiangiogenic agent that improves survival in combination with chemotherapy in first-line, regardless of RAS mutational status. Thus, the choice of an appropriate therapy after the progression to a bevacizumab or an EGFR-based first-line treatment should be evaluated according to the patient and disease characteristics and treatment aims. The continuation of bevacizumab beyond progression or its substitution with another anti-angiogenic agents has been shown to increase survival, whereas anti-EGFR monoclonals represent an option in RAS wild-type patients. In addition, specific molecular subgroups, such as BRAF-mutated and Microsatellite Instability-High (MSI-H) mCRCs represent aggressive malignancies that are poorly responsive to standard therapies and deserve targeted approaches. This review provides a critical overview about the state of the art in mCRC second-line treatment and discusses sequential strategies according to key molecular biomarkers.

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