Search Results (65)

Colorectal cancer (CRC) remains a major cause of cancer-related deaths in advanced disease, and activating KRAS/NRAS mutations limit the use of anti-EGFR antibodies to RAS–wild-type tumors. The cellular prion protein (PrP^C) has been linked to aggressive and chemoresistant CRC, but its extracellular partners and functional relevance in KRAS-mutant disease are not fully defined. Here, we examined extracellular PrP^C complexes and PrP^C-associated signaling in CRC cell lines and xenografts using a neutralizing PrP^C monoclonal antibody. Across a CRC panel that included SNU-C5/WT and its 5-fluorouracil- and oxaliplatin-resistant derivatives, HT-29 (KRAS–wild-type), and HCT-8 and LoVo (KRAS-mutant), co-immunoprecipitation showed that PrP^C forms complexes with the 37/67 kDa laminin receptor (RPSA), with PrP^C–RPSA association particularly increased in KRAS-mutant HCT-8 and LoVo cells. PrP^C protein levels were higher in KRAS-mutant HCT-8, SW620, and SNU-407 cells than in HT-29, and PrP^C neutralization reduced viability in all four lines. Accordingly, we assessed upstream RAS activity and found that active RAS (RAS-GTP) was higher in KRAS-mutant cells than in HT-29, and PrP^C treatment was associated with reduced RAS-GTP levels. In the same KRAS-mutant setting, basal AKT phosphorylation exceeded that in HT-29, and PrP^C treatment lowered AKT phosphorylation without changing total AKT. Moreover, PrP^C treatment was associated with reduced ERK1/2 phosphorylation in KRAS-mutant cells, suggesting attenuation of downstream RAS pathway output. These signaling changes coincided with a decrease in the S-phase fraction and an increase in G1. In an HCT-8 (KRAS G13D) xenograft model, PrP^C monotherapy inhibited tumor growth in a dose-dependent manner, and 5-fluorouracil (5-FU) monotherapy produced an intermediate effect. The combination of PrP^C (10 mg/kg) and 5-FU (20 mg/kg) yielded the greatest tumor growth inhibition among the tested regimens. Consistent with this enhanced tumor control, immunofluorescence of xenograft tissues showed that PrP^C, particularly with 5-FU, reduced intratumoral PrP^C and PCNA and decreased CD31-positive microvessels and α-SMA–positive vessel structures. Taken together, these findings suggest that extracellular PrP^C supports RAS–AKT signaling, proliferation, and tumor-associated angiogenesis in KRAS-mutant colorectal cancer, and that PrP^C neutralization additively enhances 5-fluorouracil activity in KRAS-mutant models. The data provide a preclinical basis for evaluating PrP^C antibodies in combination with fluoropyrimidine-based regimens in patients with KRAS-mutant CRC. Full article

In this study, three point mutations of EGFR relevant to lung cancer therapy are detected. Mutated EGFR is the target of a therapy for non-small cell lung cancer (NSCLC) using tyrosine kinase inhibitors (TKIs) as treatment drugs. Background/Objectives: Point mutations in exon 21 (L858R and L861Q) of the EGFR gene are TKI-sensitive; however, mutations in exon 20 (T790M) are TKI-resistant. Therefore, a fast detection method that classifies an NSCLC patient to be drug sensitive or drug resistant is highly clinically relevant. Methods: Probes were designed to detect three point mutations in genomic samples based on DNA hybridization on a solid surface. A method has been developed to detect single nucleotide polymorphism (SNP) for these mutation detections in the 16-channel nanobioarray chip. The wash by gold-nanoparticles (AuNP) was used to assist the differentiation detection. Results: The gold nanoparticle-assisted wash method has enhanced differentiation between WT and mutated sequences relevant to the EGFR sensitivity to tyrosine kinase inhibitors. Conclusions: The WT and mutated sequences (T790M, L858R and L861Q) in genomic samples were successfully differentiated from each other. Full article

Background: Epidermal growth factor receptor (EGFR)-targeted tyrosine kinase inhibitors (TKIs) have exhibited efficacy in EGFR-mutant non-small cell lung cancer (NSCLC) patients. However, the response is modest in patients with wild-type (wt)-EGFR, and approximately 30–40% of patients develop TKI resistance. Recently, a role for BRG1 (SMARCA4) in regulating gene expression and its frequent alteration in various cancers, including NSCLC, has been reported. Yet, its specific function in response to EGFR-TKI therapy remains elusive. Herein, we investigated the role of BRG1 in EGFR-TKI response in vitro and in vivo using lung cancer models. Methods: In vitro, A549, H358, and HCC827 cell lines that varied in their EGFR and BRG1 status were assessed for response to EGFR-TKI upon overexpression or gene silencing of BRG1 through cell viability, cell migration, and Western blotting assays. In vivo, A549 and H358 tumor xenografts that overexpressed BRG1 or had BRG1 silenced were investigated for tumor growth response to EGFR-TKI. Results: EGFRwt/BRG1mt (A549) cells were resistant to TKI, and restoration of wt-BRG1 expression reverted them to TKI sensitivity both in vitro and in vivo. In contrast, silencing of BRG1wt in H358 cells showed a tendency toward TKI resistance. Additionally, wt-EGFR and pAKT^Ser473 protein complex formation in A549 cells was disrupted with an AKT inhibitor (MK2206), resulting in enhanced cytotoxicity in vitro. Conclusions: Our study demonstrates that EGFR-TKI response in wt-EGFR cells is dictated by BRG1 status. These findings propose screening of wt-EGFR NSCLC patients for BRG1 status for identifying individuals likely to benefit from EGFR-TKI therapy versus patients who will benefit from AKT inhibitor treatment. Full article

Background: Berberine, a benzylisoquinoline alkaloid, has been traditionally used in Ayurvedic and Chinese medicine. We examined the resistance mechanisms to berberine in a panel of different cancer cells and focused on understanding its molecular mechanisms. Methods: Resazurin assay determined berberine’s cytotoxicity. Molecular docking unraveled the interaction of berberine with the BCRP transporter. Fluorescence microscopy evaluated its effect on microtubules. Further, proteomic profiling identified novel determinants of cellular response to berberine and its derivatives. Results: Cell lines overexpressing ABC transporters displayed cross-resistance to berberine compared to their counterparts. While cells over-expressing EGFR were 3.57-fold resistant, wild-type and p53 knockout cells showed similar sensitivity to berberine. P-glycoprotein/ABCB1, EGFR, and WT1 expression correlated with the log₁₀IC₅₀ values for berberine in the NCI cell line panel. Berberine was bound to the same pharmacophore of BCRP as BWQ, and live cell microscopy showed that BCRP-transfected cells did not uptake considerable amounts of berberine in contrast to wild-type cells. Berberine altered the microtubule cytoskeleton similarly to vincristine. The sensitivity of berberine and its derivatives could be predicted by 40 out of 3171 proteins. Of them, 29 proteins have been previously involved in drug resistance. Their relationship to berberine and its derivatives is novel. Conclusions: Berberine-type compounds may be new candidates against cancer; however, they may develop drug resistance. Full article

Glioblastoma (GBM) is one of the most common and aggressive primary malignant tumors of the central nervous system, accounting for about half of all gliomas in adults. Despite intensive research and advances in molecular biology, genomics, and modern neuroimaging techniques, the prognosis for patients with GBM remains extremely poor. Despite the implementation of multimodal treatment involving surgery, radiotherapy, and chemotherapy with temozolomide, the average survival time of patients is only about 15 months. This is primarily due to the complex biology of this cancer, which involves numerous genetic and epigenetic abnormalities, as well as a highly heterogeneous tumor structure and the presence of glioblastoma stem cells with self renewal capacity. Mutations and abnormalities in genes such as IDH-wt, EGFR, PTEN, TP53, TERT, and CDKN2A/B are crucial in the pathogenesis of GBM. In particular, IDH-wt status (wild-type isocitrate dehydrogenase) is one of the most important identification markers distinguishing GBM from other, more favorable gliomas with IDH mutations. Frequent EGFR amplifications and TERT gene promoter mutations lead to the deregulation of tumor cell proliferation and increased aggressiveness. In turn, the loss of function of suppressor genes such as PTEN or CDKN2A/B promotes uncontrolled cell growth and tumor progression. The immunosuppressive tumor microenvironment also plays an important role, promoting immune escape and weakening the effectiveness of systemic therapies, including immunotherapy. The aim of this review is to summarize the current state of knowledge on the epidemiology, classification, pathogenesis, diagnosis, and treatment of glioblastoma multiforme, as well as to discuss the impact of recent advances in molecular and imaging diagnostics on clinical decision-making. A comprehensive review of recent literature (2018–2025) was conducted, focusing on WHO CNS5 classification updates, novel biomarkers (IDH, TERT, MGMT, EGFR), and modern diagnostic techniques such as liquid biopsy, radiogenomics, and next-generation sequencing (NGS). The results of the review indicate that the introduction of integrated histo-molecular diagnostics in the WHO 2021 classification has significantly increased diagnostic precision, enabling better prognostic and therapeutic stratification of patients. Modern imaging techniques, such as advanced magnetic resonance imaging (MRI), positron emission tomography (PET), and radiomics and radiogenomics tools, allow for more precise assessment of tumor characteristics, prediction of response to therapy, and monitoring of disease progression. Contemporary molecular techniques, including DNA methylation profiling and NGS, enable in-depth genomic and epigenetic analysis, which translates into a more personalized approach to treatment. Despite the use of multimodal therapy, which is based on maximum safe tumor resection followed by radiotherapy and temozolomide chemotherapy, recurrence is almost inevitable. GBM shows a high degree of resistance to treatment, which results from the presence of stem cell subpopulations, dynamic clonal evolution, and the ability to adapt to unfavorable microenvironmental conditions. Promising preclinical and early clinical results show new therapeutic strategies, including immunotherapy (cancer vaccines, checkpoint inhibitors, CAR-T therapies), oncolytic virotherapy, and Tumor Treating Fields (TTF) technology. Although these methods show potential for prolonging survival, their clinical efficacy still needs to be confirmed in large studies. The role of artificial intelligence in the analysis of imaging and molecular data is also increasingly being emphasized, which may contribute to the development of more accurate predictive models and therapeutic decisions. Despite these advancements, GBM remains a major therapeutic challenge due to its high heterogeneity and treatment resistance. The integration of molecular diagnostics, artificial intelligence, and personalized therapeutic strategies that may enhance survival and quality of life for GBM patients. Full article

Colorectal cancer (CRC) classification has progressed from consensus molecular subtypes (CMS) to epithelial–intrinsic consensus molecular subtypes (iCMS) and the layered intrinsic subtype-MSI-fibrosis (IMF) system that combines intrinsic state, MSI status, and fibrosis. This article reviews biological underpinnings of iCMS/IMF, their relationships to tumor-microenvironment crosstalk, and how single-cell and spatial transcriptomics refine therapeutic stratification by resolving tumor microenvironment heterogeneity and its impact on fibrosis. Prognostic and therapeutic implications are covered, including PD-1 blockade in MSI-high (MSI-H), MAPK-directed therapy in BRAF-mutant disease, and EGFR targeting in selected RAS wild-type (WT) left-sided tumors, and we suggest decision points specifically informed by the activity of the fibrosis axis. A step-by-step procedure is presented for the analysis of bulk and single-cell RNA and formalin-fixed, paraffin-embedded (FFPE) resources, along with open-source tools and reporting standards to make iCMS/IMF calling reproducible in clinics and trials. Future outlooks are outlined with near-term biomarker–drug hypotheses for microsatellite-stable (MSS)-iCMS3 and high fibrosis tumors and key gaps to close for clinical translation. This review outlines a roadmap for precision medicine in colorectal cancer by leveraging the iCMS/IMF framework to integrate pathology and digital pathology, molecular diagnostics, and therapy mapping with FAP-targeted imaging and therapy. Full article

Ischemia–reperfusion injury (IRI) is a leading cause of acute kidney injury (AKI) and a major driver of progression to chronic kidney disease (CKD). Oxidative stress is recognized as a central mediator of this transition. Engulfment and Cell Motility 1 (ELMO1) regulates cytoskeletal remodeling and reactive oxygen species generation through Rac1 activation, but its contribution to CKD progression remains poorly defined. To investigate this, we established a unilateral renal IRI model in wild-type (WT) and Elmo1-overexpressing (Elmo1^H/H) mice and evaluated kidney function one and four months post-IRI. Compared with WT, Elmo1^H/H mice developed more severe kidney dysfunction, including an elevated plasma cystatin C and urinary albumin-to-creatinine ratio, reduced estimated glomerular filtration rate (eGFR), and pronounced fibrosis and glomerular injury observed by light and electron microscopy. Molecular analysis confirmed the dysregulation of redox-related pathways by RT-qPCR, with RNA sequencing showing enrichment of oxidative stress signatures. A subset of mice received chronic vitamin B12 (B12) supplementation following IRI to evaluate its therapeutic potential. Vitamin B12 supplementation improved kidney function, reduced fibrosis, preserved glomerular structure, and normalized the expression of antioxidant genes in both groups. These findings identify Elmo1 as a driver of redox-mediated kidney injury and support vitamin B12 as a promising antioxidant therapy for AKI-to-CKD progression. Full article

Background/Objectives: Liquid biopsy using cfDNA has emerged as a promising, minimally invasive alternative to traditional tissue biopsy for detecting cancer-associated mutations. However, the extremely low proportion of mutant DNA in cfDNA poses a major challenge for accurate detection, especially when using conventional sequencing methods. To address this limitation, we sought to develop a highly sensitive diagnostic strategy to selectively enrich rare mutant sequences and improve the detection of clinically important mutations in patients with NSCLC. Methods: We established a CRISPR/Cas12a-based diagnostic system designed to selectively cleave WT DNA, thereby increasing the relative abundance of mutant DNA in cfDNA samples. Following Cas12a-mediated WT cleavage, the remaining DNA was subjected to PCR amplification for mutation identification. The system was applied to plasma cfDNA from blood samples of 48 NSCLC patients to evaluate its ability to detect two major EGFR mutations: L858R and exon 19 deletion. Results: The CRISPR/Cas12a-based diagnostic system effectively identified low-frequency EGFR mutations in cfDNA. Specifically, all 7 L858R-positive samples and 6 out of 11 samples harboring exon 19 deletions—previously validated through tissue biopsy—were successfully detected. This demonstrated a high degree of concordance between our liquid biopsy approach and conventional diagnostic methods. Conclusions: Our findings highlight the potential of the CRISPR/Cas12a-based mutation enrichment system as a powerful tool for detecting rare oncogenic mutations in liquid biopsy samples. This technique enhances diagnostic sensitivity and could be broadly applicable for the non-invasive detection of various genetic alterations in cancer and other diseases. Full article

Non-small cell lung cancer (NSCLC) is the leading cause of cancer-related mortality worldwide. Accurate determination of epidermal growth factor receptor (EGFR) mutation status is essential for selecting patients eligible for tyrosine kinase inhibitors (TKIs). However, invasive genotyping is often limited by tissue accessibility and sample quality. This study presents a non-invasive machine learning model combining clinical data, CT morphological features, and radiomic descriptors to predict EGFR mutation status. A retrospective cohort of 138 patients with confirmed EGFR status and pre-treatment CT scans was analyzed. Radiomic features were extracted with PyRadiomics, and feature selection applied mutual information, Spearman correlation, and wrapper-based methods. Five Random Forest models were trained with different feature sets. The best-performing model, based on 11 selected variables, achieved an AUC of 0.91 (95% CI: 0.81–1.00) under stratified five-fold cross-validation, with an accuracy of 0.88 ± 0.03. Subgroup analysis showed that EGFR-WT had a performance of precision 0.93 ± 0.04, recall 0.92 ± 0.03, F1-score 0.91 ± 0.02, and EGFR-Mutant had a performance of precision 0.76 ± 0.05, recall 0.71 ± 0.05, F1-score 0.68 ± 0.04. SHapley Additive exPlanations (SHAP) analysis identified tobacco use, enhancement pattern, and gray-level-zone entropy as key predictors. Decision curve analysis confirmed clinical utility, supporting its role as a non-invasive tool for EGFR-screening. Full article

Colorectal cancer (CRC) remains a major cause of cancer-related mortality. Cetuximab improves survival by combining EGFR inhibition with immune activation. This study evaluated the influence of killer cell immunoglobulin-like receptor (KIR)-mediated immune responses on cetuximab efficacy in 124 metastatic CRC patients: 55 with wild-type (WT) KRAS and 69 with KRAS mutations. Peripheral blood was genotyped for 19 KIR genes and relevant HLA alleles, focusing on key KIR–HLA interactions (2DL1–C2, 3DL1–Bw4, 3DS1–Bw4). KRAS-WT patients showed better outcomes, receiving more treatment cycles (median: 17 vs. 4) and showing slower disease progression (60% vs. 92.8% at 12 months). WT patients had higher frequencies of inhibitory KIRs and the Bw4 allele, with KIR3DS1–Bw4 heterozygosity linked to longer survival (p = 0.013). In KRAS-mutant patients, heterozygous KIR genotypes (AB) and mixed A/B semi-haplotypes were associated with improved survival (p = 0.002). Multivariate analysis confirmed KIR3DS1–Bw4 as a favorable factor in WT patients and AB genotypes as beneficial in KRAS-mutants. In conclusion, KIR–HLA interactions significantly impact cetuximab efficacy in metastatic CRC, with distinct immunogenetic profiles in WT and KRAS-mutant patients. These results highlight the potential of KIR–HLA profiling to guide personalized treatment strategies. Full article

Abnormal expressions and genetic mutations of EGFR are broadly involved in the progression of many human solid tumors, which has led to the development of small molecule inhibitors (TKIs). However, patients’ tumors usually develop resistance to targeted therapeutic TKIs after a period of treatment, mostly due to secondary mutations in EGFR. To date, three major and prevalent point mutations in EGFR, including L858R, T790M, and C797S, impact the use of TKIs in non-small cell lung cancer patients. Although at least four generations of TKIs have been designed and developed by targeting these mutations, how each mono, dual, or triple variant responds to clinical TKIs remains largely undeciphered. To fill this gap, we constructed a series of EGFR mutants and assessed their responses to clinical TKIs in vitro. The first-generation TKI, erlotinib, completely blocked the autophosphorylation of WT, L858R, C797S, and C797S/L858R, but only partially, if at all, in EGFR containing the T790M mutation alone or in combination. The third generation, osimertinib, completely abolished the autophosphorylation of WT, T790M, L858R, and T790M/L858R. It also significantly inhibited C797S and C790S/L858R, but had no effect on T790M/C797S or T790M/C797S/L858R. EAI045, as the fourth-generation TKI, almost completely inhibited WT and all mutants in complete growth media, but EGF-mediated phosphorylation of WT, C797S, and C797S/L858R were only partially inhibited in quiescence media, while the other mutants were fully inhibited. Furthermore, the abolishment of the enhanced tolerance to Dox in cells transiently expressing T790M/L858R and T790M/C797S/L858R by EAI045 suggests that their enhanced autophosphorylation is involved in their resistant ability. These findings provide some insights into how patients carrying typical mutations should be correctly and efficiently treated and why patients present side effects (because of non-specific inhibitory effects on cells without EGFR mutations). Full article

Non-small-cell lung cancer (NSCLC) can harbour different HER2 alterations: HER2 protein overexpression (2–35%), HER2 gene amplification (2–20%), and gene mutations (1–4%). The discovery of the HER2 gene in the 1980s raised great expectations for the treatment of several tumours. However, it was only in 2004 that HER2 mutations were identified, and they currently represent a key druggable target in NSCLC. Despite numerous strengths, there is only one FDA/EMA-approved targeted therapy, an antibody-drug conjugate (ADC) called trastuzumab deruxtecan for pretreated patients with HER2 mutant NSCLC. In the first-line treatment, the standard of care (SoC) remains chemotherapy with or without immunotherapy. In the past, pan-HER tyrosine kinase inhibitors (TKIs) were extensively studied with poor results. But, two newly developed HER2-specific TKIs with low EGFR WT inhibition (BAY2927088 and zongertinib) reported encouraging results and received the breakthrough therapy designation from the FDA. Ongoing clinical trials are investigating new agents. This review focuses on HER2 alterations. Additionally, the anti-HER2 therapies explored so far will be discussed in detail, including the following: HER2 inhibitors (pan-inhibitors and selective inhibitors), monoclonal antibodies (mAbs), and ADCs. A section of this paper is dedicated to the role of immunotherapy in HER2-altered NSCLC. The last section of this paper focuses on the drugs under development and their challenges. Full article

Lung adenocarcinoma (LUAD) is driven by epidermal growth factor receptor (EGFR) mutations, making it a key therapeutic target. ADAM9, a member of the A disintegrin and metalloproteinase (ADAM) family, facilitates the release of growth factors and was implicated in activating the EGFR-mediated progression in several cancer types. In this study, we explored potential associations among ADAM9 single-nucleotide polymorphisms (SNPs), the EGFR mutation status, and the clinicopathological progression of LUAD in a Taiwanese population. In total, 535 LUAD patients with various EGFR statuses were enrolled, and allelic distributions of ADAM9 SNPs—located in promoter and intron regions, including rs78451751 (T/C), rs6474526 (T/G), rs7006414 (T/C), and rs10105311 (C/T)—were analyzed using a TaqMan allelic discrimination assay. We found that LUAD patients with at least one polymorphic G allele in ADAM9 rs6474526 had a lower risk of developing EGFR mutations compared to those with the wild-type (WT) TT genotype. Furthermore, G-allele carriers (TG + GG) of rs6474526 were associated with an increased likelihood of developing larger tumors (T3 or T4), particularly among patients with mutant EGFR. Conversely, in patients with WT EGFR, carriers of the T allele in rs10105311 had a lower risk of progressing to advanced stages (stage III or IV). Among females or non-smokers, G-allele carriers of rs6474526 demonstrated a higher risk of advanced tumor stages and distant metastases. In clinical data from the Genotype-Tissue Expression (GTEx) database, individuals with the polymorphic T allele in rs6474526 showed reduced ADAM9 expression in lung and whole blood tissues. Screening the genotype of rs6474526 in a set of LUAD cell lines revealed that cells carrying at least one minor G allele exhibited higher ADAM9 levels compared to those with the TT genotype. Additionally, analyses using TCGA and CPTAC databases revealed elevated ADAM9 expression in LUAD specimens compared to normal tissues. Elevated protein levels were correlated with advanced T stages, pathological stages, and worse prognoses. In summary, our results suggest that ADAM9 genetic variants of rs6474526 may affect ADAM9 expression and are associated with the EGFR mutation status. Both rs6474526 and rs10105311 were correlated with disease progression in LUAD patients. These variants could serve as potential biomarkers for predicting clinical outcomes. Full article

Background/Objectives: The aberrant expression and activation of HER family members is a known major oncogenic pathway for the proliferation, progression, and metastasis of a wide range of human malignancies. In this study, our aim was to examine the relative expression and prognostic significance of all members of the HER family, the type III EGFR mutant (EGFRvIII), and the putative stem cell markers CD44 and CD109 in patients with glioblastoma. Methods: The expression levels of wild-type EGFR (wtEGFR), HER2, HER3, HER4, EGFRvIII, CD44, and CD109 were determined in tumour specimens from 80 patients by immunohistochemistry. The staining was scored based on the percentage of positive tumour cells, the intensity, and the cellular location of immunostaining. The association between the expression level of the biomarkers and patient overall survival was evaluated using Chi-squared, Kaplan–Meier survival curves, and log-rank tests. Results: At a cut-off value of ≥5% with positive staining, 46% (wtEGFR), 75% (HER2), 19% (HER3), 71% (HER4), 85% (EGFRvIII), 95% (CD44), and 16% (CD109) of the cases were positive for these biomarkers. Interestingly, at the same cut-off value, the expression of wtEGFR in these patients was accompanied by co-expression with HER2 (35%), HER3 (0%), HER4 (30%), EGFRvIII (36%), CD44 (44%), HER2/EGFRvIII (28%), HER2/CD44 (31%), and EGFRvIII/CD44 (36%). In addition, the expression of EGFRvIII was accompanied by co-expression with HER2 (65%), HER3 (15%), HER4 (63%), CD44 (83%), CD109 (16%), wtEGFR/HER2 (28%), and 55% of the cases had co-expression of EGFRvIII/HER2/HER4/CD44. With the exception of HER2 expression, at cut-off values of ≥5% of tumour cells with positive staining, which was associated with better overall survival [HR = 0.57 (p = 0.038), HR = 0.56 (p = 0.034)], there was no significant association between the expression of other members of the HER family, EGFRvIII, CD44, and CD109 on the overall survival in both univariate and multivariate analysis. Conclusions Our results suggest that the co-expression of different members of the HER family, with EGFRvIII, CD44, and CD109, occurs in patients with glioblastoma. As the results of therapy with EGFR inhibitors have not been encouraging in patients with a brain tumour, further investigation should determine whether the co-expression of such biomarkers can be of predictive value for the response to the therapy with various types of HER inhibitors and their potential as therapeutic targets for co-targeted therapy. Full article

Background/Objectives: In metastatic colorectal cancer (mCRC), liquid biopsy has enabled the identification of “neo-RAS-Wild-Type (WT)”, a transient phase characterized by the disappearance of RAS mutations, with significant clinical implications for re-sensitization to EGFR blockade. This study aimed to prospectively track the kinetics of neo-RAS-WT in circulating tumor DNA (ctDNA) among RAS-mutant mCRC patients receiving first-line and subsequent systemic therapies. Methods: A total of 380 serial blood samples from 35 patients were analyzed. Each patient provided a median of 10 ctDNA samples at three-month intervals during first-line and subsequent therapies. The patients were categorized into three groups: neo-RAS-WT, non-shedding, and persistent mutant. Results: During first-line treatment, 68% of patients transitioned to RAS-WT. Of these, 17% were neo-RAS-WT, while the majority were classified as non-shedding. In the second-line setting, the percentage of neo-RAS-WT increased to 34%, which dropped to 8.5% during the third-line setting. The duration of the neo-RAS-WT window was significantly longer in neo-RAS-WT patients compared to non-shedding patients (p = 0.037). Patients who achieved RAS-WT status had improved progression-free survival (PFS) compared to those with persistent mutant, with significant differences observed across all treatment lines: first-line (p = 0.004), second-line (p < 0.0001), and third-line (p = 0.001). Multivariate analysis revealed that the duration of the RAS-WT window correlated with extended first-line PFS (HR: 0.78; 95% CI: 0.69–0.89; p < 0.0001), second-line PFS (HR: 0.66; 95% CI: 0.52–0.84; p = 0.001), and overall survival (OS) (HR: 0.82; 95% CI: 0.72–0.95; p = 0.006). Conclusions: While the neo-RAS-WT window is transient in non-shedding, it is durable in neo-RAS-WT patients, persisting until disease progression. These findings highlight the potential utility of ctDNA testing in refining treatment strategies for RAS-mutant mCR. Full article