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

HER2-targeted therapy in colorectal cancer: a comprehensive review

Colorectal cancer (CRC) is the third most common cancer and the second leading cause of cancer-related deaths worldwide. Despite treatment advancements in the last decades, CRC remains heterogeneous with significant clinical and genetic diversity. Human epidermal growth factor receptor 2 (HER2) proto-oncogene plays a critical role, as its amplification or overexpression leading to abnormal cell proliferation and tumorigenesis. HER2 overexpression or amplification is identified in 2-4% of metastatic CRCs (mCRC) patients, representing a potential therapeutic target. It is also associated with resistance against epidermal growth factor receptor (EGFR)-targeted therapies like cetuximab and panitumumab, for treatment of RAS wild-type mCRC. Although HER2-positive mCRC is rare, assessing HER2 levels is important. Furthermore, anti-HER2 therapies exhibited non-toxic profile and high efficacy in chemorefractory cases. This review delves into modern management of anti-HER2 therapies in CRC with a particular focus on recent advances and current knowledge about the prognostic and predictive value of HER2.

Personalised medicine based on host genetics and microbiota applied to colorectal cancer

Colorectal cancer (CRC) ranks second in incidence and third in cancer mortality worldwide. This situation, together with the understanding of the heterogeneity of the disease, has highlighted the need to develop a more individualised approach to its prevention, diagnosis and treatment through personalised medicine. This approach aims to stratify patients according to risk, predict disease progression and determine the most appropriate treatment. It is essential to identify patients who may respond adequately to treatment and those who may be resistant to treatment to avoid unnecessary therapies and minimise adverse side effects. Current research is focused on identifying biomarkers such as specific mutated genes, the type of mutations and molecular profiles critical for the individualisation of CRC diagnosis, prognosis and treatment guidance. In addition, the study of the intestinal microbiota as biomarkers is being incorporated due to the growing scientific evidence supporting its influence on this disease. This article comprehensively addresses the use of current and emerging diagnostic, prognostic and predictive biomarkers in precision medicine against CRC. The effects of host genetics and gut microbiota composition on new approaches to treating this disease are discussed. How the gut microbiota could mitigate the side effects of treatment is reviewed. In addition, strategies to modulate the gut microbiota, such as dietary interventions, antibiotics, and transplantation of faecal microbiota and phages, are discussed to improve CRC prevention and treatment. These findings provide a solid foundation for future research and improving the care of CRC patients.

BRAF mutations and the association of V600E with CD133 and CDX2 expression in a Pakistani colorectal carcinoma cohort

BACKGROUND

Despite a high incidence of colorectal carcinoma, data regarding genetic aberrations in colorectal carcinoma (CRC) patients in Pakistan is scarce. This study aimed to determine the frequency of BRAFV600E mutations in colorectal carcinoma tissue in the Pakistani population and to associate BRAFV600E expression with CD133, a marker of colorectal stem cells, and CDX2 marker of differentiation.

METHODS

Sanger Sequencing of exon 15 (426 bp) including the hotspot V600E was performed on formalin-fixed-paraffin-embedded (FFPE) CRC tissue samples of 115 patients. The samples were subjected to immunohistochemistry (IHC) to assess the expression of BRAFV600E, CDX2, and CD133. Additionally, homology modelling and docking were performed to investigate novel deletions revealed in sequencing.

RESULTS

Twenty-four (20.8%) BRAF variants were identified in the coding region, with V600E mutations detected in 14 (12.2% )cases (GenBank: PP003258.1; Pop Set: 2678087296). Moreover, a wide spectrum of novel non-V600E mutations (8.6%) were identified, including deletions and missense variations. In-silico analysis revealed that due to large deletions in the coding region of three samples, the affinity of the anti-BRAF drugs (Encorafenib and Vemurafenib) for the active site decreased in comparison to the wild type. The IHC analysis showed that BRAFV600E expression was significantly associated with CD133 expression (χ2(1, n=115) = 26.351; p = < 0.001) and with CDX2 expression (χ2(1, n=115) = 14.88; p = 0.001). Multivariate analysis using binary logistic regression revealed association of BRAFV600E mutations with age (OR = 1.123; CI = 1.024-1.232; p = 0.014), gender (OR = 0.071; CI = 0.006-0.831; p = 0.035), grade (0.007; CI = 0-0.644) and CD133 expression (OR = 65.649; CI = 2.153-2001.556; p = 0.016).

CONCLUSION

The present study demonstrates a notably high V600E frequency (12.2%) in comparison to global reported data, which ranges from 0.4 to 18%. This finding reflects the importance of upfront BRAF testing of the genetically distinct population of Pakistan. Previously unreported mutations identified in the sample may be of clinical significance and warrant further investigation. The concomitant high expression and significant association between CD133 and BRAFV600E represent vital actionable genes that may be targeted together to improve CRC patient management.

Advances in Precision Medicine Approaches for Colorectal Cancer: From Molecular Profiling to Targeted Therapies

Precision medicine is transforming colorectal cancer treatment through the integration of advanced technologies and biomarkers, enhancing personalized and effective disease management. Identification of key driver mutations and molecular profiling have deepened our comprehension of the genetic alterations in colorectal cancer, facilitating targeted therapy and immunotherapy selection. Biomarkers such as microsatellite instability (MSI) and DNA mismatch repair deficiency (dMMR) guide treatment decisions, opening avenues for immunotherapy. Emerging technologies such as liquid biopsies, artificial intelligence, and machine learning promise to revolutionize early detection, monitoring, and treatment selection in precision medicine. Despite these advancements, ethical and regulatory challenges, including equitable access and data privacy, emphasize the importance of responsible implementation. The dynamic nature of colorectal cancer, with its tumor heterogeneity and clonal evolution, underscores the necessity for adaptive and personalized treatment strategies. The future of precision medicine in colorectal cancer lies in its potential to enhance patient care, clinical outcomes, and our understanding of this intricate disease, marked by ongoing evolution in the field. The current reviews focus on providing in-depth knowledge on the various and diverse approaches utilized for precision medicine against colorectal cancer, at both molecular and biochemical levels.

Biologics, theranostics, and personalized medicine in drug delivery systems

The progress in human disease treatment can be greatly advanced through the implementation of nanomedicine. This approach involves targeted and cell-specific therapy, controlled drug release, personalized dosage forms, wearable drug delivery, and companion diagnostics. By integrating cutting-edge technologies with drug delivery systems, greater precision can be achieved at the tissue and cellular levels through the use of stimuli-responsive nanoparticles, and the development of electrochemical sensor systems. This precision targeting - by virtue of nanotechnology - allows for therapy to be directed specifically to affected tissues while greatly reducing side effects on healthy tissues. As such, nanomedicine has the potential to transform the treatment of conditions such as cancer, genetic diseases, and chronic illnesses by facilitating precise and cell-specific drug delivery. Additionally, personalized dosage forms and wearable devices offer the ability to tailor treatment to the unique needs of each patient, thereby increasing therapeutic effectiveness and compliance. Companion diagnostics further enable efficient monitoring of treatment response, enabling customized adjustments to the treatment plan. The question of whether all the potential therapeutic approaches outlined here are viable alternatives to current treatments is also discussed. In general, the application of nanotechnology in the field of biomedicine may provide a strong alternative to existing treatments for several reasons. In this review, we aim to present evidence that, although in early stages, fully merging advanced technology with innovative drug delivery shows promise for successful implementation across various disease areas, including cancer and genetic or chronic diseases.