Anti-EGFR Antibodies in the Management of Advanced Colorectal Cancer

Translational Advances in Oncogene and Tumor-Suppressor Gene Research

Cancer, characterized by the uncontrolled proliferation of cells, is one of the leading causes of death globally, with approximately one in five people developing the disease in their lifetime. While many driver genes were identified decades ago, and most cancers can be classified based on morphology and progression, there is still a significant gap in knowledge about genetic aberrations and nuclear DNA damage. The study of two critical groups of genes-tumor suppressors, which inhibit proliferation and promote apoptosis, and oncogenes, which regulate proliferation and survival-can help to understand the genomic causes behind tumorigenesis, leading to more personalized approaches to diagnosis and treatment. Aberration of tumor suppressors, which undergo two-hit and loss-of-function mutations, and oncogenes, activated forms of proto-oncogenes that experience one-hit and gain-of-function mutations, are responsible for the dysregulation of key signaling pathways that regulate cell division, such as p53, Rb, Ras/Raf/ERK/MAPK, PI3K/AKT, and Wnt/β-catenin. Modern breakthroughs in genomics research, like next-generation sequencing, have provided efficient strategies for mapping unique genomic changes that contribute to tumor heterogeneity. Novel therapeutic approaches have enabled personalized medicine, helping address genetic variability in tumor suppressors and oncogenes. This comprehensive review examines the molecular mechanisms behind tumor-suppressor genes and oncogenes, the key signaling pathways they regulate, epigenetic modifications, tumor heterogeneity, and the drug resistance mechanisms that drive carcinogenesis. Moreover, the review explores the clinical application of sequencing techniques, multiomics, diagnostic procedures, pharmacogenomics, and personalized treatment and prevention options, discussing future directions for emerging technologies.

Canonical MAPK signaling in auditory neuropathy

Auditory neuropathy (AN) is an under-recognized form of hearing loss characterized by lesions in inner hair cells (IHCs), ribbon synapses and spiral ganglion neurons (SGNs). The lack of a targeted therapy for AN has increased the need for a better understanding of the pathogenic mechanism of AN. As mitogen-activated protein kinase (MAPK) signaling is ubiquitous in many biological processes, its alteration may facilitate the pathogenesis of multiple sites in AN. Here, we summaries the characteristics of AN under different molecular bases and first explore the mechanism of MAPK at different lesion sites. Alterations of extracellular signal-regulated kinase (ERK)/MAPK occur in IHCs and SGNs, whereas modulations of p38 and c-Jun NH2-terminal kinase (JNK) were found in ribbon synapses and SGNs. In conclusion, inductive MAPK alterations in the pathogenesis and development of AN are likely to represent a potential therapeutic target to guide the development of treatments.

Negative Hyperselection in Metastatic Colorectal Cancer for First-Line Anti-EGFR Therapy: A Narrative Review

Colorectal cancer (CRC) remains a leading cause of cancer-related mortality, with metastatic disease posing significant therapeutic challenges. While anti-EGFR therapy has improved outcomes for patients with RAS and BRAF wild-type tumors, resistance remains a major hurdle, limiting treatment efficacy. The concept of negative hyperselection has emerged as a refinement of molecular profiling, identifying additional genomic alterations-such as HER2 and MET amplificationsand MAP2K1 mutations-that predict resistance to anti-EGFR agents. Studies incorporating these expanded assessments have demonstrated that nearly half of patients with RAS/BRAF wild-type tumors harbor alternative resistance biomarkers, underscoring the need for expanded selection criteria. Liquid biopsies, particularly circulating tumor DNA (ctDNA) analysis, have revolutionized precision oncology by providing a minimally invasive, real-time assessment of tumor dynamics. ctDNA-based hyperselection enables the detection of resistance-associated alterations, guiding treatment decisions with greater accuracy than conventional tissue biopsies. Recent trials support the predictive value of ctDNA-defined negative hyperselection, revealing superior outcomes for patients stratified through liquid biopsy. This narrative review explores the evolving role of molecular hyperselection in first-line anti-EGFR therapy, emphasizing the integration of ctDNA to refine patient selection, enhance therapeutic efficacy, and pave the way for personalized treatment strategies in metastatic CRC.

Precision medicine in colorectal cancer: genomics profiling and targeted treatment

Precision medicine has revolutionized the treatment of colorectal cancer by enabling a personalized approach tailored to each patient's unique genetic characteristics. Genomic profiling allows for the identification of specific mutations in genes such as KRAS, BRAF, and PIK3CA, which play a crucial role in cell signaling pathways that regulate cell proliferation, apoptosis, and differentiation. This information enables doctors to select targeted therapies that inhibit specific molecular pathways, maximizing treatment effectiveness and minimizing side effects. Precision medicine also facilitates adaptive monitoring of tumor progression, allowing for adjustments in therapy to maintain treatment effectiveness. While challenges such as high costs, limited access to genomic technology, and the need for more representative genomic data for diverse populations remain, collaboration between researchers, medical practitioners, policymakers, and the pharmaceutical industry is crucial to ensure that precision medicine becomes a standard of care accessible to all. With continued advances and support, precision medicine has the potential to improve treatment outcomes, reduce morbidity and mortality rates, and enhance the quality of life for colorectal cancer patients worldwide.

Investigation of the correlation between AGRN expression and perineural invasion in colon cancer

Background and Purpose

Colon cancer is one of the most common gastrointestinal malignancies. According to the traditional view, the primary modes of transmission include direct dissemination, hematogenous metastasis, and lymph node metastasis. In recent years, the role of perineural invasion (PNI) in the spread and metastasis of tumors has received immense attention. However, there are still relatively few reports on the potential mechanisms and biomarkers of PNI occurrence and development in colon cancer.

Method

We identified genes linked to the onset and progression of PNI in colon cancer using bioinformatics tools and extensive databases. Gene function enrichment analysis was used to explore the potential roles of these genes in tumor proliferation, invasion, and PNI. A collection of postoperative pathological specimens from colon cancer patients who underwent surgery, related clinicopathological data, and immunohistochemistry were used to validate AGRN expression in PNI tissues.

Results

Bioinformatics analysis revealed that AGRN is overexpressed in colon cancer tissues and correlates with poor patient prognosis. The findings from gene association and enrichment studies indicate that AGRN and its associated genes may play a role in PNI development and progression in colon cancer by simultaneously enhancing tumor cell invasion and neural cell growth. Immunohistochemical analysis of clinical samples confirmed that AGRN expression is elevated in colon cancer tissues with PNI.

Conclusion

We found that AGRN is significantly overexpressed in colon cancer tissues exhibiting PNI and is linked to poor patient survival. AGRN and its related genes may contribute to PNI by promoting tumor cell invasion and neural cell growth. Hence, AGRN may play a crucial role in the initiation and progression of PNI in colon cancer.

Neo-RAS Wild Type or RAS Conversion in Metastatic Colorectal Cancer: A Comprehensive Narrative Review

The management of metastatic colorectal cancer in patients harboring RAS mutations primarily involves chemotherapy, often combined with bevacizumab, as a standard first-line treatment. However, emerging evidence suggests that tumors in a subset of these patients may experience a conversion from RAS-mutant status to RAS wild type (wt) during or after chemotherapy, a process referred to as "RAS conversion" or "neo-RAS wt". Understanding the mechanisms driving the neo-RAS wt phenomenon is crucial for its application in personalized medicine. Hypotheses suggest that selective pressure from chemotherapy may lead to a decrease in the number of mutant RAS clones or an outgrowth of pre-existing RAS wt clones. Further research is needed to validate these mechanisms and understand the impact of the neo-RAS wt phenomenon on long-term outcomes, such as overall survival and progression-free survival. This review provides a comprehensive overview of the current understanding of the neo-RAS wt phenomenon, including its incidence, potential mechanisms, and clinical implications.

Redefining Therapeutic Approaches in Colorectal Cancer: Targeting Molecular Pathways and Overcoming Resistance

Colorectal cancer (CRC) arises through a combination of genetic and epigenetic alterations that affect key pathways involved in tumor growth and progression. This review examines the major molecular pathways driving CRC, including Chromosomal Instability (CIN), Microsatellite Instability (MSI), and the CpG Island Methylator Phenotype (CIMP). Key mutations in genes such as APC, KRAS, NRAS, BRAF, and TP53 activate signaling pathways like Wnt, EGFR, and PI3K/AKT, contributing to tumorigenesis and influencing responses to targeted therapies. Resistance mechanisms, including mutations that bypass drug action, remain challenging in CRC treatment. This review highlights the role of molecular profiling in guiding the use of targeted therapies such as tyrosine kinase inhibitors and immune checkpoint inhibitors. Novel combination treatments are also discussed as strategies to improve outcomes and overcome resistance. Understanding these molecular mechanisms is critical to advancing personalized treatment approaches in CRC and improving patient prognosis.

Efficacy and Safety of Anti-EGFR Therapy Rechallenge in Metastatic Colorectal Cancer: A Systematic Review and Meta-Analysis

BACKGROUND

Colorectal cancer (CRC) represents the second leading cause of cancer-related mortality worldwide, with a significant portion of patients presenting with metastatic disease at diagnosis. Resistance to initial anti-EGFR therapy, a key treatment for RAS wild-type metastatic CRC, remains a major challenge. This study aimed to assess the efficacy and safety of rechallenge with anti-EGFR therapy in patients with metastatic CRC who have progressed after prior treatments.

METHODS

A systematic search was conducted across PubMed, Web of Science, Cochrane, and Scopus. Studies were included if they were randomized controlled trials (RCTs) or observational studies involving patients with EGFR-mutated metastatic CRC who received anti-EGFR therapy as a rechallenge. Endpoints included objective response rate (ORR), disease control rate (DCR), and the incidence of adverse events. Statistical analyses were performed using the DerSimonian/Laird random effect model, with heterogeneity assessed via I2 statistics. R, version 4.2.3, was used for statistical analyses.

RESULTS

Fourteen studies were included with 520 patients; 50.3% were male, and the median age was 63 years old. The median progression-free survival (mPFS) ranged between 2.4 and 4.9 months, while the median overall survival (mOS) ranged from 5 to 17.8 months. Our pooled analysis demonstrated an objective response rate (ORR) of 17.70% (95% CI, 8.58-26.82%) and a disease control rate (DCR) of 61.72% (95% CI, 53.32-70.11%), both with significant heterogeneity (I2, 84% and 80%, respectively; p < 0.01). In the subgroup analysis, cetuximab showed an ORR of 18.31% (95% CI, 4.67-31.94%), and panitumumab an ORR of 10.9% (95% CI, 0.00-26.82%), while the combination of both resulted in an ORR of 29.24% (95% CI, 0.00-65.84%). For DCR, cetuximab resulted in 62.1% (95% CI, 49.32-74.87%), panitumumab in 63.05% (95% CI, 52.13-73.97%), and the combination in 60.34% (95% CI, 31.92-88.77%), all with significant heterogeneity. Adverse events included anemia (15.39%), diarrhea (4.20%), hypomagnesemia (6.40%), neutropenia (22.57%), and skin rash (13.22%).

CONCLUSIONS

Rechallenge with anti-EGFR therapy in metastatic CRC patients shows moderate efficacy with manageable safety profiles. These findings highlight the need for careful patient selection and monitoring to optimize outcomes. Further studies are warranted to refine strategies for maximizing the therapeutic benefits of anti-EGFR rechallenge.

An Efficient Method for Vault Nanoparticle Conjugation with Finely Adjustable Amounts of Antibodies and Small Molecules

Vaults are eukaryotic ribonucleoproteins consisting of 78 copies of the major vault protein (MVP), which assemble into a nanoparticle with an about 60 nm volume-based size, enclosing other proteins and RNAs. Regardless of their physiological role(s), vaults represent ideal, natural hollow nanoparticles, which are produced by the assembly of the sole MVP. Here, we have expressed in Komagataella phaffi and purified an MVP variant carrying a C-terminal Z peptide (vault-Z), which can tightly bind an antibody's Fc portion, in view of targeted delivery. Via surface plasmon resonance analysis, we could determine a 2.5 nM affinity to the monoclonal antibody Trastuzumab (Tz)/vault-Z 1:1 interaction. Then, we characterized the in-solution interaction via co-incubation, ultracentrifugation, and analysis of the pelleted proteins. This showed virtually irreversible binding up to an at least 10:1 Tz/vault-Z ratio. As a proof of concept, we labeled the Fc portion of Tz with a fluorophore and conjugated it with the nanoparticle, along with either Tz or Cetuximab, another monoclonal antibody. Thus, we could demonstrate antibody-dependent, selective uptake by the SKBR3 and MDA-MB 231 breast cancer cell lines. These investigations provide a novel, flexible technological platform that significantly extends vault-Z's applications, in that it can be stably conjugated with finely adjusted amounts of antibodies as well as of other molecules, such as fluorophores, cell-targeting peptides, or drugs, using the Fc portion as a scaffold.

Options in Targeted Therapy for Advanced Cholangiocarcinoma: A 2024 Update

Bile duct carcinomas have a different prognosis and genetic profile depending on their location; intrahepatic/extrahepatic or at the level of the gallbladder. Although in recent years there have been important advances in first-line therapy, second-line therapy in cholangiocarcinoma does not currently have a standard. Therefore at this level, there is an acute need for personalized treatment. The present article is a narrative review that aims to list the newest targeted therapeutic options for this type of cancer, based on identified genetic alterations. The literature selected for analysis includes phase 2 or 3 studies with targeted therapy in this disease and original articles no older than three years that describe the prevalence of the most common gene alterations in this type of cancer. PubMed/Medline, Scopus, and Clarivate-Web of Science databases were searched and keywords such as "cholangiocarcinoma," "biliary cancer," "targeted therapy," "gene amplifications," and "mutations" were used. This narrative review was designed taking into account the SANRA (Scale for the Assessment of Narrative Review Articles) criteria. The conclusions lead to the fact that next-generation sequencing testing is of particular usefulness in cholangiocarcinoma. Bile duct cancers are rich in targetable genetic alterations, and their treatment is in constant change, although much of the current data comes from phase II studies. There is a great need for the current options to be analyzed in phase III studies. Hence, the need of the oncological community to stay informed about targeted treatment options for cholangiocarcinoma is supported by the present article.

The effective combination therapies with irinotecan for colorectal cancer

Colorectal cancer is the third most common type of cancer worldwide and has become one of the major human disease burdens. In clinical practice, the treatment of colorectal cancer has been closely related to the use of irinotecan. Irinotecan combines with many other anticancer drugs and has a broader range of drug combinations. Combination therapy is one of the most important means of improving anti-tumor efficacy and overcoming drug resistance. Reasonable combination therapy can lead to better patient treatment options, and inappropriate combination therapy will increase patient risk. For the colorectal therapeutic field, the significance of combination therapy is to improve the efficacy, reduce the adverse effects, and improve the ease of treatment. Therefore, we explored the clinical advantages of its combination therapy based on mechanism or metabolism and reviewed the rationale basis and its limitations in conducting exploratory clinical trials on irinotecan combination therapy, including the results of clinical trials on the combination potentiation of cytotoxic drugs, targeted agents, and herbal medicine. We hope that these can evoke more efforts to conduct irinotecan in the laboratory for further studies and evaluations, as well as the possibility of more in-depth development in future clinical trials.